CA2056583A1 - Hose coupling and method of making the same - Google Patents
Hose coupling and method of making the sameInfo
- Publication number
- CA2056583A1 CA2056583A1 CA002056583A CA2056583A CA2056583A1 CA 2056583 A1 CA2056583 A1 CA 2056583A1 CA 002056583 A CA002056583 A CA 002056583A CA 2056583 A CA2056583 A CA 2056583A CA 2056583 A1 CA2056583 A1 CA 2056583A1
- Authority
- CA
- Canada
- Prior art keywords
- terminal portion
- layer
- coupling
- retainer
- sealing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000008878 coupling Effects 0.000 title claims abstract description 43
- 238000010168 coupling process Methods 0.000 title claims abstract description 43
- 238000005859 coupling reaction Methods 0.000 title claims abstract description 43
- 238000004519 manufacturing process Methods 0.000 title description 2
- 239000000463 material Substances 0.000 claims abstract description 69
- 239000003566 sealing material Substances 0.000 claims abstract description 44
- 238000007789 sealing Methods 0.000 claims abstract description 37
- 239000004033 plastic Substances 0.000 claims abstract description 9
- 229920003051 synthetic elastomer Polymers 0.000 claims abstract description 9
- 239000005061 synthetic rubber Substances 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims description 19
- 229920002379 silicone rubber Polymers 0.000 claims description 14
- 229920002943 EPDM rubber Polymers 0.000 claims description 8
- 229920001973 fluoroelastomer Polymers 0.000 claims description 8
- 239000004952 Polyamide Substances 0.000 claims description 4
- 229920002647 polyamide Polymers 0.000 claims description 4
- 239000007769 metal material Substances 0.000 claims description 3
- 239000011346 highly viscous material Substances 0.000 claims description 2
- 230000003014 reinforcing effect Effects 0.000 claims description 2
- 239000012530 fluid Substances 0.000 description 25
- 230000009471 action Effects 0.000 description 18
- 230000008901 benefit Effects 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000002826 coolant Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 239000000314 lubricant Substances 0.000 description 3
- 210000002445 nipple Anatomy 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 238000007710 freezing Methods 0.000 description 2
- 230000008014 freezing Effects 0.000 description 2
- 238000003780 insertion Methods 0.000 description 2
- 230000037431 insertion Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 238000007493 shaping process Methods 0.000 description 2
- 238000003892 spreading Methods 0.000 description 2
- 230000007480 spreading Effects 0.000 description 2
- 229920001897 terpolymer Polymers 0.000 description 2
- 239000004753 textile Substances 0.000 description 2
- 235000007575 Calluna vulgaris Nutrition 0.000 description 1
- 229920002449 FKM Polymers 0.000 description 1
- 101100334774 Methanosaeta harundinacea (strain 6Ac) filI gene Proteins 0.000 description 1
- 241000206607 Porphyra umbilicalis Species 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 239000003431 cross linking reagent Substances 0.000 description 1
- 235000013870 dimethyl polysiloxane Nutrition 0.000 description 1
- 239000004205 dimethyl polysiloxane Substances 0.000 description 1
- 239000013013 elastic material Substances 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- HQQADJVZYDDRJT-UHFFFAOYSA-N ethene;prop-1-ene Chemical group C=C.CC=C HQQADJVZYDDRJT-UHFFFAOYSA-N 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 230000009969 flowable effect Effects 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- -1 silicon rubber Chemical class 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L33/00—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses
- F16L33/18—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses characterised by the use of additional sealing means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L33/00—Arrangements for connecting hoses to rigid members; Rigid hose connectors, i.e. single members engaging both hoses
- F16L33/02—Hose-clips
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Joints That Cut Off Fluids, And Hose Joints (AREA)
Abstract
ABSTRACT
A hose coupling wherein the terminal portion of a rigid metallic or plastic pipe has one or more external annular retainers close to its free end and is surrounded by a sleeve-like layer of sealing material, such as synthetic rubber, which retains its sealing properties within the entire temperature range of between approximately -80°C and +260°C. The terminal portion of the pipe and its layer of sealing material are inserted into the terminal portion of a hose prior to the application of an annular clamp which surrounds the terminal portion of the hose and urges it against the external surface of the layer of sealing material.
The retainer or retainers are located between the properly applied clamp and the free end of the terminal portion of the pipe. The layer of sealing material can but need not extend beyond the clamp, e.g., all the way to the free end of the terminal portion of the hose, and the materials of the hose and layer are selected in such a way that the sealing material does not adhere to the hose. The sealing material of the layer adheres to the terminal portion of the pipe.
A hose coupling wherein the terminal portion of a rigid metallic or plastic pipe has one or more external annular retainers close to its free end and is surrounded by a sleeve-like layer of sealing material, such as synthetic rubber, which retains its sealing properties within the entire temperature range of between approximately -80°C and +260°C. The terminal portion of the pipe and its layer of sealing material are inserted into the terminal portion of a hose prior to the application of an annular clamp which surrounds the terminal portion of the hose and urges it against the external surface of the layer of sealing material.
The retainer or retainers are located between the properly applied clamp and the free end of the terminal portion of the pipe. The layer of sealing material can but need not extend beyond the clamp, e.g., all the way to the free end of the terminal portion of the hose, and the materials of the hose and layer are selected in such a way that the sealing material does not adhere to the hose. The sealing material of the layer adheres to the terminal portion of the pipe.
Description
2~S8~
The invention relates to cou~lings in general, and more particularly to improvements in couplings which can be utilized with advanta~e to establish a sealing connection between the terminal portion of a hose or another flexible first tubular component and the terminal portion of a nipple or another rigid or suhstantially rigid second tubular component which is insertable into the terminal portion of the first tubular component.
Still more particularly, the invention relates to improvements in couplings wherein the terminal portion of the second tuhular component is provided with one or more annular external retainers in the form of ring-shaped ribs or the like. The invention also relates to a method of making the above outlined coupling.
It is already known to establish a sealing connection hetween a flexible hose, which is made of ethylene propylene terpolymer and has one or more inserts of textile material or the like, and a metallic pipe. The terminal portion of the pipe is inserted into the terminal portion of the hose, and the terminal portion of the hose is thereupon surrounded by a clamp which is tightened to urge the internal surface of the hose into sealing engagement with the external surface of the pipe. Such couplings are sa-tisfactory at room temperature and at certain other temperatures above the freezing point;
however, they are likely to permit leakage of confined fluid if the latter is maintained at an elevated pressure while the temperature around the coupling drops below or well ~elow 0C. The reason is that the material of the hose between the clamp and the ad~acent portion of the pipe ~ 3~ ~
shrinks as the temperature of the coupling decreases, and this brings about a reduction or termination of sealing engagement hetween the internal surace of the hose and the external surface of the pipe. In other words, the thickness of that part of the hose which is confined within the clamp decreases to such an extent that it is less than the radial distance between the internal surface of the clamp and the external surface of the pipe, i.e., the afore-mentioned part of the hose ceases to sealingly engage the external surface of the pipe and the confined fluid is free to escape into the surrounding atmosphere. Leakage of confined fluid can take place even if pronounced cooling results in some or even pronounced contraction of that part of the hose which is surrounded by the clamp.
If the material of the hose retains at least some elasticit~ in spite of pronounced cooling, the confined fluid causes the hose to expand against the internal surface of the clamp and to thus establish a path for the escape of fluid from the interior of -the composite conduit including the pipe and the hose. If the temperature rises, the terminal portion of the hose ~xpands and the part of the hose hetween the clamp and the pipe reestablishes a sealing connection to ~revent further escape of confined fluid.
~ nother drawback of heretofore known couplings of the above outlined character is that the terminal portion of the hose is likely to undergo permanent deformation if the temperature around and/or within such terminal portion rises to or above 90C. Lack of ade~uate elasticity of the material of the hose is highly undesirable because this can lead to the development of leaks even at temperatures above the fxeezing point.
German Utility Model No. 19 51 368 of Daimler-senz Aktiengesellschaft (publishea September 4, 1963) discloses a hose coupling wherein the hose is desiyned to stand elevated pressures of 200-300 atmo~spheres and is to convey a fluid whose temperature fluctuates within a range of up to 140C. The publication discloses the use of a sealing compound, such as silicon rubber, which is self hardening to exhibit a shore hardness of approximately 70. Other characteristics of the sealing compound are not discussed.
One feature of the present invention residès in the provislon of a couplin~ which comprises a first tubular component having a deformable first terminal portion, a second tubular component having a second terminal portion provided with at least one annular external retainer and received in the first terminal ~ortion, and a suhstantially sleeve-like layer between the two terminal portions. ~he layer consists of a sealin~ material whose sealing characteristics remain at least suhstantially intact or acceptable at temperatures within the ~ntire range of between approximately +260C
and -80C, at least within the entire range of between approximately`~l40C and -40C.
The couplin~ preferably further comprises a clamp which surrounds the first terminal portion. The at least one annular retainer is then disposed between the free end of the second terminal portion (such free 3~ end is located within the first tubular component) and the clamp.
The layer is or can be elastic, and the irst terminal portion preferably consists of a material which does not exhiblt a tendency to adhere -to the sealing material.
The layer can extend all the way or nearly all the way from the free end of the first terminal portion to the at least one annular retainer.
The sealing material can be selected in such a way that it adheres to the second terminal portion. For example, the sealing material can constitute a hardened originally highly viscous substance.
The first terminal portion (or the entire first tubular component) can be made of a material inclùding EPDM and silicon rubher~ and such first terminal portion can contain at least one reinforci~g layer of filamentary material (e~g., one or more layers of tex~ile material).
The second terminal portion (or the entire second tubular component) can be made of a metallic or rigid plastic material. A presently preferred plastic material is polyamide, The sealing material can be selected from the group consisting of synthetic rubber and fluoroelastomers.
The synthetic rubher is or can be silicon rubber.
Another feature of the present invention resides in the provision of a method o-f es-tablishing a sealing connection between a first tubular component hàving a deformable first terminal portion and a second tubular component having a second tubular portion provided with at least one annular external retainer and having an open end ad~acent the at least one retainer. The method comprises the steps of applying around the second kerminal portion a mass of hardenable viscous sealin~ material whose sealàng characteristics remain at least substantially unchanged or at least acceptable within the entire range of at least between approximately -40C and ~140C so that the at least one retainer is located bekween the open end of the second terminal portion and the applied mass, and introducing the second terminal portion into the first terminal portion. The introducing step is or can be carried out prior to hardening of the material of the mass.
The method can further comprise the step of converting an effective amount of sealing material into a layer prior ko hardenlng of the sealing material. The introducing~step is or can be carried out subsequent to the converting skep and subse~uent to hardening of the sealing material, The sealing material can be selected from the group consisting of synthetic rubber and fluoroelastomers.
The synthetic rubber is preferably silicon rubber.
The first terminal portion or the entire first tubular component can consist of a material which is selected rom the group consisting of EPDM and silicon rubber.
A further feature of the invention resides in the provision of a method of establishing a sealing connection batwe~n a firsk tubular component (e.g., a hose) having a deformable first terminal portion and a second tubular component (e.~., a pipe~ having a second terminal portion provided with at least one external retainer ancl having a Eree end. The method comprises the steps of establishing an annular space arownd the second terminal portion at suGh location that the at least one retainer is located between the annular space and the free end of the second terminal portion, introducing (e.g., injecting) into the annular space a hardenable (settable) viscous sealing material having sealing characteristics which remain at least substantially intact (or at :Least acceptable) at temperatures within the entire range of between approximately -80C and *260~C (at least within the entire range of between approximately -40C and -~-140C) so that the introduced material forms a ~L.
suhstantiaily tubular laye,r which preferably adheres to : the external surface of the second~tubular portion, and inserting the at least one retainer, the layer and the second terminal portion into the first'terminal portion.
The establishing step can include placing a tubular shaping or spr~adin~ tool or mold around the second terminal portion, and such method further comprises the step of remo~-ing the tool prior to the inser~ing step. The method : can also cdmprise the ste~ of causing or permitting the sealing material to sat prior to the inserting step. The first termihal portion can consist of or can contain a : material which is se~ected rom the group consisting of : EPDM and silicon ru~ber, he second terminal portion can consist of or can contain a metallic or plas~ic material ~e.~ olvamide), and the sealing material can be sel~cted from the group consisting of silicon rubber and fluoro-elastomers.
The novel ~eatures which are considered as ~3~8~
characteristic of the invention are set forth in particular i.n the appended claims. The improved coupling itself, however, both as to its construction and the mode of making the same! together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawing.
FIG. 1 is a fragmentary partly elevational and partly axial sectional view of the tubular components of the novel hose coupling prior to introduction of the terminal portion of the ri.gid tubular component into the terminal portion of the flexible tubular component;
- 7a -~3 ~
FIG. 2 is a fragmentary axial sectional view of the assembled coupling;
FIG. 3 is a similar fragmentary axial sectional view of a modified fully assembled coupling; and FIG. 4 is a fragmentary axial sectional view of the rigid tubular component and of a tool which is used to shape sealing material prior to introduction of the terminal portion of the rigid tubular component into the flexible tubular component.
FIG. 1 shows one terminal portion 3a of a first tubular component 3 which constitutes a normally flexible hose, and one terminal portion la of a second tubular component 1 which constitutes a ri~id metallic pipe. The terminal portion la;has a free end lb and is provided with a single external annular retainer 2 in the form of a circumferentiallv complete rib. A ring-shaped mass 4 of sealing material surrounds the terminal portion la and is applled at a lacation such that the retainer 2 is located be~ween the mass 4 and the free end lb. The mass 4 consists of a highly viscous hardenable - sealin~ material which preferably exhibits a pronounced tendency to adhere to the metallic material of the terminal portion la while exhibiting a much less pronounced tendency (or ~o tendency at all) to adhere to the material of the terminal portion 3a, In order to assemble the coupling, the terminal portion la is introduced into the terminal portion 3a whereby the latter spreads the material of the mass 4 to convert it into a relatively thin elongated sleeve-like layer 4a ~see FIG. 2) which preferably extends from the _ ~ _ retainer 2 and all the way or substantially all the way to the free end 3b of the terminal portion 3a. The last step o completihg the assemhly of the coupling includes the application of a clamping device 5 (hereinafter called clamp for short) which includes a relatively wide strap 6 with two radially outwardly extending end portions 7 (only one shown in FI~. 2). The end portions 7 are urged toward or against each other by one or more fasteners 8, e.g., a bolt and nut, a screw or the like.
The material of the mass 4 and of the layer 4a is silicon rubber whose sealing characteristics remain at least substantially unchanged within a wide range of temperatures, such as ~ithin the entire range of between approximately -80C and ~260~Cr and at least within the entire range of between -40C and ~140C.- The material of the mass 4 can be a heat-pol~marizable silicon rubber which is vulcanized with peroxides at 200C. ~owever, it is equally possible to employ a cold-vulcaniæable sllicon rubber. A cold vulcaniz-able silicon rubber can constitute a solvent-free p~ste-like twin-component mass with one or more specific cross-linking agents or a single-component mass which is adapted to be cross-linked under the influence of air. In accordance with a presently preferred embodiment, the mass 4 and the layer 4a can consist of dimethyl polysiloxane with cross-linking a~ent and one or more special fillers.
As shown, the tubular component 1 is made of a metallic material. The hose 3 is made of ethylane propylene terpolymer (EPDM) with one or more reinforGing inserts of filamentary material (e.g., a fabric, not shown).
As can be seen in FIG. l, the mass 4 is applied 5f~3 in such ~uantity that it forms a ring having an outer diameter which at least approximates but can exceed the outer diameter of the retainer 2. The material of the mass 4 is tough (highly vlscous), and such material is applled to the external surface of the terminal portion la c].ose to the retainer 2 so that it is located between the retainer and the locus of application of the strap 6 of the clamp 5 when the coupling is fully assembled in a manner as shown in FIG. 2~ As already explained above, the terminal portion 3a of the hose 3 is slipped over the terminal ~ortion la prior to setting of the material of the mass 4. This ensures that the sealing material acts as a lubricant to facilitate application of the hose onto the pipe. Moreover, this entails conversion of the ring-shaped mass 4 into the sleeve-like layer 4a of constant or nearly constant thickness which strongly adheres to the external surface of thé terminal portion la all the way from the retainer 2 to the free end 3b of the terminal portion 3a. Thus, the terminal portion 3a does not or need not contact the terminal portion la between the free end 3b and the top land of the retainer 2. The clamp 5 is applied subseqllent to setting of the material of the la~er 4a, and the fastener or fasteners 8 are tightened to ensure that the internal surface of the strap 6 bears against the external surface of adjacent part of terminal portion 3a so that the latter is urged against the external surface of the sleeve-like layer 4a.
However, it is e~ually within the purview of the invention to apply and tighten the clamp 5 prior to setting of the 3~ sealing material of the layer 4a, 8 ~
FIG. 2 shows that the major part of the layer 4a constitutes a relatively thin film of constant or nearly constant thickness and that the end portion of the layer 4a adjacent the retainer 2 is thicker so that it filIs the annular space between the left-hand flank of the retainer 2 and the adjacent part of internal surface of the terminal portion 3a. When the hardening or setting of the sealing material of the layer 4a is completed, the latter constitutes an elastic sheath or sleeve which strongly adheres to the external surface of the terminal portion la but exhibits a much less pronounced tendency to adhere tor does not adhere at all) to the internal surface o the terminal portion 3a.
The tubular component 1 can constitute a nipple which is rigid with the cooling unit for the engine in a motor ~ehicle. The hose 3 can serve to establish a path for the flow of coolant between the cooler and the engine block. It has been ound that, i the improved coupling is used in a motor vehicle between the cooler and the engine, the material of the terminal portion 3a of the hose 3 contracts in response to coollng (e.g./ in winter while the engine is idle) so that the volume of the terminal portion 3a decreases. In the absence of the la~ter 4a, the terminal portion 3a would become disengaged rom the external surface of the terminal portion la, i.e., the ~ealing action would no longer exist and the terminal portion 3a would he loosely held between the strap 6 of the clamp 5 and the terminal portion la.
However, the layer 4a prevents-~anyleakage of fluid from the interior of the conduit including the pipe 1 and the 2 ~ 8 3 hose 3, even during the interval immediately following startin~ of the engine, i~e~, during the initial stage of pressurization of coolant which flows between the cooler and the engine block ~namely during that stage when the coolant is compelled to flow but is yet to be heated). Such hlghly desirahle sealing action during the just described stage of operation of the engine is attributable to the presence of the layer 4a, particularly of that portion of ~he layer 4a which extends between the clamp 5 and the retainer 2. The reason is that the layer 4a retains its elasticity at low or very low temperatures, namely at those temperatures when the elasticity of the material of the hose 3 is zero or close to zero. Thus, the layer 4a continues to urge the adjacent part of the terminal portion 3a into sealing engagement with the internal surface of the strap 6, and the layer portion between the strap 6 and the retainer 2 continues to exhiblt sufficient elasticit~ to sealingly engage the internal surface of the terminal portion 3a. As the pressure of fluid in the pipe l and hose 3 rises, the elastic layer 4a undergoes radial expansion so that the sealing actiQn of this layer between the retainer 2 and the strap 6- increases with rising pressure of the confined fluid. Since the thickness of the layer 4a is normally more pronounced in the region between the clamp 5 and the retainer 2, such porti~n of the layer furnishes a highly satisfactory sealing action which prevents lea~age of confined fluid at temperatures at which the coupling would be incapable of confining the fluid if the layer 4a were omitted.
As the tem~erature of the coniined fluid rises, the temperature of the coupling also rises~ i.e., the material of the terminal portion 3a expands and the sealing action in the region of the clamp 5 becomes even more satisfactory. This prevents leakage of confined fluid even if the pressure of such fluid rises sufficiently to cause the terminal portion 3a to expand radially outwardly so that it is disengaged from the terminal portion la in the region to the right of the retainer 2, at the retainer 2 and/or between the retainer 2 and the clamp 5.
An important advantage of a sealing material which is highly viscous during application of the mass 4 is that such material can fill any and all depressions (such as axially, circumferentially and/or otherwise oriented grooves, blind holes and the like) in the external surface of the terminal portion la during conversion into the sleeve-like layer 4a of FIG. 2. Thus, it is not necessary to treat the external surface of the terminal portion la to a high degree of precision finish ~(in fact, it is not even necessary to remove ~urrs) because any and aLl unevennesses are compensated for by the material of the mass 4 which fills such unevennesses during conversion into the elongated sleeve-like layer 4a of FIG. 2. Since the material of the sleeve-like layer 4a adheres to the material of the terminal portion la, fluid which is confined in the tubular components 1 and 3 cannot escape between the layer 4a and the terminal portion Ia even if the temperature of the improved coupling is reduced well below the freezing point, e.g., all the way to -80C.
$ ~
It will be noted that the sleeve like layer 4a enhances khe sealing action in the region within the strap 6 of the clamp 5 as well as at both sides of such strap, especially between the strap and the retainer 2. The sealing action of that portion of the layer 4a which is located between the strap 6 and the retainer 2 is independent of the sealing action of the other portion of such layer. This is desirable and advantageous for the aforediscussed reasons, i.e., the layer 4a ensures the establishment of a satisfactory sealing action when the temperature of the terminal portion 3a of the hose 3 is so low that the sealing action between the hose and the strap 6 i5 negligible or nil. At such time, the preferably ; elastomeric layer 4a ensures the establishment of a reliable sealing action in the region between the strap 6 and the retainer 2. That portion of the layer 4a which extends between the retainer 2 and the strap 6 compensates for shrinkage of the sur~rounding part of the terminal portion 3a and prevents leakag@ of confined fluid even if the pressure of such fluid happens to rise while the - temperature of the terminal portion 3a is well below O~C, e.g., at -40~C~ Under such circumstances, the material of the layer 4a between the retainer 2 an~ the strap 6 acts not unllke a radially inward extension of the surrounding part of the terminal portion 3a and enables the coupling to prevent leakage of confined fluid at temperatures which are much too low for the establishment of a satisfactory sealing action by resorting to heretofore known hose couplings.
The layer 4a is equally useful when the temperature 2 ~ 3 of or at the coupling rises well above 0C, e.g., to 90C or higher. Thus, the material of the laver 4a tends to expand within the confines of the strap 6 (such tendency is shared by the m~terial of the termi~al portion 3a) so that the sealing action in the region of the clamp 5 is highly satisfactory. In addition, the material of the Iayer 4a tends to expand in the region between the strap 6 and the retainer 2 so that the sealing action of the coupling is enhanced between the clamp 5 and the free end Ib of the terminal portion la.
Though it is possible to employ a sleeve-like layer 4a which is not elastic at all or exhibits a minimal amount of elasticity, an elastic layer is preferred at this time because such layer constitutes a highly effective barrier against leakage of fluid from the interior of the pipe 1 and hose 3 toward and out-wardly beyond the clamp 5. Thus~ if the pressure of confined fluid rises, suc~ fluid might be capable of flowing around the retainer 2 and of acting upon the material of the layer 4a between the retainer 2 and the strap 6. The elas~ic material of the layer 4a yields radially inwardly and outwardly to bear against the internal surface of the terminal portion 3a and against the external surface of the terminal portion la with the result that it reliably prevents leakage of pressurized fluid all the way to the strap 6. If the pressure of confined fluid decreases, the thickness of the layer 4a between the retainer 2 and the strap 6 also increases to thus enhance the sealing action in a different way. If some elastic material of the la~er 4a was expelled from 2 ~ 3 the r~gion at the left-hand flank of the retainer 2 (as viewed in FIG. 2), such material returns due to elasticity of the layer 4a and this ensures that the space at the left-hand flank of the retainer 2 is filled with elastic sealing material to ensure the establishment of a reliable sealing action.
An advanta~e of the feature that the material of the layer 4a does not tend to adhere to the terminal portion 3a is that the terminal portion 3a can be more readily slipped onto the layer 4a prior to application of the clamp 5. In addition, the terminal portion la and its sleeve-like layer 4a can be more readily extracted from the terminal portion 3a as soon as the clamp 5 is removed or loosened.
Since the layer ~a preferably extends all the way to the free end 3b of the terminal portion 3a, the terminal portion la can be readily extracted from the hose 3, as soon as the clamp 5 is removed or loosened, because the terminal portion 3a cannot contact the terminal portion la (excep~ perhaps in the narrow region between the top land of the retainer 2 and the free end lb). This is desirable and advantageous because the terminal portion 3a would normally tend to adhere to the termi~al portion la after a relatively long intervàI of application of the clamp S. The mass 4 acts not unlike a body of lubricant during initial application of the terminal portion 3a over the terminal portion la to thus ensure that the terminal portion la can be introduced into the hose with a minimum of effort; at such time, the terminal portion 3a spreads the material of the mass 4 over the external surface of the terminal portion la to thus convert the mass into the sleeve-like layer 4a.
A sealing material which exhibits a preferably pronounced tendency to adhere to the (metallic or plastic) material of the terminal portion la exhibits the additional advantage that the likelihood of leakage of pressurized fluid from its path in the pipe 1 and hose 3 into the surrounding atmosphere by flowing directly along -the external surface of the terminal portion la is practically nil. Once the material of the layer 4a sets, this layer can be considered an inte~ral part of the terminal portion la with attendant advantages as regards the combined sealing action of the parts la and 4a.
Furthermore, the layer 4a then compensates for eventual unevennesses in the external surface of the terminal portion la even if the latter was not subjected to any finishing or precision finishing treatment such as removal of scale, deburring, polishing, grinding and the like.
It has been found that the sealing action of the impro~ed coupling is highly satisfactory if the terminal portion la is made of a metallic or plastic material (..i~ the latter instance preferably a polyamide), if the terminal portion 3a of the hose is made of .silicon ruhber or EPDM, and if the layer 4a consists of synthetic rubber or a fluoroelastomer.
It has also been found that the terminal portion 3a is capable of converting the mass 4 into a suhstantially uniform layer 4a (without pushing a substantial percentage of the material of the mass 4 in front of its free end 3b) during insertion of the terminal portion la into the hose 3. This is believed to be attrihutable to the selection of a highly viscous sealing material which acts as a lubricant whiIe it is being converted into a sleeve-like layer that preferably extends all the way from the top land of the retainer 2 to the free end 3b.
FI~. 3 shows a portion of a modified coupling.
The difference between the couplings of FIGS. 2 and 3 is that the metallic component li includes a terminal portion la' with two ~eighboring circumferentially extending annular external retainers 2 one of which is adjacent the free end lb' and the other of which is located betw~en the one retainer and the strap 6 of the clamp 5. The mass of highly viscous sealing material which is applied to the exterior of the terminal portion la'- includes a first section 4~ in the annular depression or valley between the retainers 2 and a second sec~ion which is converted into the sleeve-like layer or film 4a' in response to introduction of the t~rm.inal portion la' into the terminal portion 3a of the hose 3.
The arrangement may be such that the mass of sealing material is applied only in the valley between the two retainers 2 but in such guantity that a certain percentage of such mass is entrained by the internal surface of the.terminal portion 3a while the latter is being slipped onto the terminal portion la' (or while the terminal portion la' is in the process of being lntroduced into the terminal portion 3a) so that the thus separated portion of the mass 4' hetween the retainers 2 forms the sleeve-like layer or film 4a'. In other words, the valley 2 ~
or groove ~etween the two retainers 2 can serve primarily as a receptacle for that portion of the (originally much larger) mass 4' whlch is not converted into the layer 4a'.
This is often desira~le and advantageous because the provision of a receptacle for surplus sealing material ensures that the surplus cannot penetrate into the interior of the conduit (i.e., beyond the free end lb' of the terminal portion la 7 ) during introduction of the terminal portion la' into the terminal portion 3a. In addition, the sealing material which remains between the retainers 2 contributes to the establishment of an even more satisfactory and more reliable sealing action within the desired temperature range.
FIG. 4 shows a substantially cylindrical shaping or spreading tool 9 which can be utilized to convert one or more streams or flows of sealing material into a layer 4a even before the terminal portion la of the tubular component 1 is introduced into the terminal portion 3a (not shown in FIG. 4) of the hose 3. The internal surface of the shapihg or spreading tool 9 is configurated in such a way that it is complementary to the desired external surface of the layer 4a. The internal surface is provided with annular boundaries 10 and 11 at the axial ends of the layer 4a. The tool 9 is preferably assembled of two or more shells or sections which have abutting radially and axially extending surfaces and permit rapid application of the tool over, as well as rapid disengagement of the tool from, the terminal portion la of the pi~e 1.
The internal surface of the tool 9 is preferably coated with a layer of material (indicated by the legend "FILM"~ which does not adhere to the material of the layer 4a to thus permit rapid separation of the tool from the finished layer 4a. The material of such layer can be permitted to set prior to or after insertion of the terminal portion la into the termlnal portion 3a of a hose 3. The arranyement is preferahly such that, when the tool 9 is properlv applied over the terminal portion la, a re~uisite amount of highly viscous sealing material is admitted into the annular space between the tool and the terminal portion la so that the injected material fills the annular space and forms the layer 4a. In other words, if one employs the tool 9 or an analogous tool, the application of a mass 4 can be dispensed with because one or more streams or flows of injected sealing material can be directly converted into a sleeve-like layer 4a which is ready to be surrounded by the terminal portion of a hose. An opening or inlet for admission of flowable sealing material into the space between the tool 9 and the terminal portion la is shown b~ broken lines~ as at 13.
The tool 9 can be provided with one~ two or more openings or inlets for admission of sealing material.
An advantage of the tool 9 and of the method which was described with reference to FIG.4 is that the la~er 4a can be formed in advance, e.g., in the plant which makes the coolers for the engines of motor vehicles.
This renders it possible to more rapidly assemble the hose 3 with the terminal portion la of FIG. 4 because the latter already carries a inished layer 4a which is ready to enter the terminal portion of the hose prior to - 20 ~
application of the clamp 5 or another suitable clamp (or two or more clamps). Application of the sleeve-like layer 4a to the terminal portion la prior to assembling the ~ubular component 1 with another tubular component (such as the hose 3 of FIGS. 1 to 3) is desirable and advantageous in many instances, for example~ if the hose 3 is to be connec~ed to a nipple (1) of a water pump in a motor vehicle.
The tubular component 1 can constitute a length of pipe which has two terminal portions each of which is provided with one or more external retainers 2. This enables such tubular component to be used as an element of a coupling between two flexible hoses or the like, i.e., each terminal portion of the just described tubular component with two terminal portions (each having at lea.st one retainer 2 or an analogous retainer3 can be introduced into a discrete hose.
The tubular component 1 can also be made of a rigid or praatically rigid plastic or other material (e.g., polyamide), i.e., it is not always necessary to couple the hose 3 to a metallic pipe. Furthermore, the hose 3 (or at least the terminal portion 3a of this hose3 can be made of the same material as the mass 4, e.g., silicon ru~ber, and is ~preferably provided with one or more reinforcing inserts of filamentary material or the like~ e.g., with one or more reinrorcing inserts of textile material. Still further, the sleeve-like layer can be made of any one of a variety of different materials including ~ynthetic ru~ber and many others, e.g., a fluoroelastomer. Suitable elastomers are those known as ~ ~ ~r~ r~
TEFLON (Trademark) and VITON (Trademark) which are made and sold by DuPont.
'
The invention relates to cou~lings in general, and more particularly to improvements in couplings which can be utilized with advanta~e to establish a sealing connection between the terminal portion of a hose or another flexible first tubular component and the terminal portion of a nipple or another rigid or suhstantially rigid second tubular component which is insertable into the terminal portion of the first tubular component.
Still more particularly, the invention relates to improvements in couplings wherein the terminal portion of the second tuhular component is provided with one or more annular external retainers in the form of ring-shaped ribs or the like. The invention also relates to a method of making the above outlined coupling.
It is already known to establish a sealing connection hetween a flexible hose, which is made of ethylene propylene terpolymer and has one or more inserts of textile material or the like, and a metallic pipe. The terminal portion of the pipe is inserted into the terminal portion of the hose, and the terminal portion of the hose is thereupon surrounded by a clamp which is tightened to urge the internal surface of the hose into sealing engagement with the external surface of the pipe. Such couplings are sa-tisfactory at room temperature and at certain other temperatures above the freezing point;
however, they are likely to permit leakage of confined fluid if the latter is maintained at an elevated pressure while the temperature around the coupling drops below or well ~elow 0C. The reason is that the material of the hose between the clamp and the ad~acent portion of the pipe ~ 3~ ~
shrinks as the temperature of the coupling decreases, and this brings about a reduction or termination of sealing engagement hetween the internal surace of the hose and the external surface of the pipe. In other words, the thickness of that part of the hose which is confined within the clamp decreases to such an extent that it is less than the radial distance between the internal surface of the clamp and the external surface of the pipe, i.e., the afore-mentioned part of the hose ceases to sealingly engage the external surface of the pipe and the confined fluid is free to escape into the surrounding atmosphere. Leakage of confined fluid can take place even if pronounced cooling results in some or even pronounced contraction of that part of the hose which is surrounded by the clamp.
If the material of the hose retains at least some elasticit~ in spite of pronounced cooling, the confined fluid causes the hose to expand against the internal surface of the clamp and to thus establish a path for the escape of fluid from the interior of -the composite conduit including the pipe and the hose. If the temperature rises, the terminal portion of the hose ~xpands and the part of the hose hetween the clamp and the pipe reestablishes a sealing connection to ~revent further escape of confined fluid.
~ nother drawback of heretofore known couplings of the above outlined character is that the terminal portion of the hose is likely to undergo permanent deformation if the temperature around and/or within such terminal portion rises to or above 90C. Lack of ade~uate elasticity of the material of the hose is highly undesirable because this can lead to the development of leaks even at temperatures above the fxeezing point.
German Utility Model No. 19 51 368 of Daimler-senz Aktiengesellschaft (publishea September 4, 1963) discloses a hose coupling wherein the hose is desiyned to stand elevated pressures of 200-300 atmo~spheres and is to convey a fluid whose temperature fluctuates within a range of up to 140C. The publication discloses the use of a sealing compound, such as silicon rubber, which is self hardening to exhibit a shore hardness of approximately 70. Other characteristics of the sealing compound are not discussed.
One feature of the present invention residès in the provislon of a couplin~ which comprises a first tubular component having a deformable first terminal portion, a second tubular component having a second terminal portion provided with at least one annular external retainer and received in the first terminal ~ortion, and a suhstantially sleeve-like layer between the two terminal portions. ~he layer consists of a sealin~ material whose sealing characteristics remain at least suhstantially intact or acceptable at temperatures within the ~ntire range of between approximately +260C
and -80C, at least within the entire range of between approximately`~l40C and -40C.
The couplin~ preferably further comprises a clamp which surrounds the first terminal portion. The at least one annular retainer is then disposed between the free end of the second terminal portion (such free 3~ end is located within the first tubular component) and the clamp.
The layer is or can be elastic, and the irst terminal portion preferably consists of a material which does not exhiblt a tendency to adhere -to the sealing material.
The layer can extend all the way or nearly all the way from the free end of the first terminal portion to the at least one annular retainer.
The sealing material can be selected in such a way that it adheres to the second terminal portion. For example, the sealing material can constitute a hardened originally highly viscous substance.
The first terminal portion (or the entire first tubular component) can be made of a material inclùding EPDM and silicon rubher~ and such first terminal portion can contain at least one reinforci~g layer of filamentary material (e~g., one or more layers of tex~ile material).
The second terminal portion (or the entire second tubular component) can be made of a metallic or rigid plastic material. A presently preferred plastic material is polyamide, The sealing material can be selected from the group consisting of synthetic rubber and fluoroelastomers.
The synthetic rubher is or can be silicon rubber.
Another feature of the present invention resides in the provision of a method o-f es-tablishing a sealing connection between a first tubular component hàving a deformable first terminal portion and a second tubular component having a second tubular portion provided with at least one annular external retainer and having an open end ad~acent the at least one retainer. The method comprises the steps of applying around the second kerminal portion a mass of hardenable viscous sealin~ material whose sealàng characteristics remain at least substantially unchanged or at least acceptable within the entire range of at least between approximately -40C and ~140C so that the at least one retainer is located bekween the open end of the second terminal portion and the applied mass, and introducing the second terminal portion into the first terminal portion. The introducing step is or can be carried out prior to hardening of the material of the mass.
The method can further comprise the step of converting an effective amount of sealing material into a layer prior ko hardenlng of the sealing material. The introducing~step is or can be carried out subsequent to the converting skep and subse~uent to hardening of the sealing material, The sealing material can be selected from the group consisting of synthetic rubber and fluoroelastomers.
The synthetic rubber is preferably silicon rubber.
The first terminal portion or the entire first tubular component can consist of a material which is selected rom the group consisting of EPDM and silicon rubber.
A further feature of the invention resides in the provision of a method of establishing a sealing connection batwe~n a firsk tubular component (e.g., a hose) having a deformable first terminal portion and a second tubular component (e.~., a pipe~ having a second terminal portion provided with at least one external retainer ancl having a Eree end. The method comprises the steps of establishing an annular space arownd the second terminal portion at suGh location that the at least one retainer is located between the annular space and the free end of the second terminal portion, introducing (e.g., injecting) into the annular space a hardenable (settable) viscous sealing material having sealing characteristics which remain at least substantially intact (or at :Least acceptable) at temperatures within the entire range of between approximately -80C and *260~C (at least within the entire range of between approximately -40C and -~-140C) so that the introduced material forms a ~L.
suhstantiaily tubular laye,r which preferably adheres to : the external surface of the second~tubular portion, and inserting the at least one retainer, the layer and the second terminal portion into the first'terminal portion.
The establishing step can include placing a tubular shaping or spr~adin~ tool or mold around the second terminal portion, and such method further comprises the step of remo~-ing the tool prior to the inser~ing step. The method : can also cdmprise the ste~ of causing or permitting the sealing material to sat prior to the inserting step. The first termihal portion can consist of or can contain a : material which is se~ected rom the group consisting of : EPDM and silicon ru~ber, he second terminal portion can consist of or can contain a metallic or plas~ic material ~e.~ olvamide), and the sealing material can be sel~cted from the group consisting of silicon rubber and fluoro-elastomers.
The novel ~eatures which are considered as ~3~8~
characteristic of the invention are set forth in particular i.n the appended claims. The improved coupling itself, however, both as to its construction and the mode of making the same! together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawing.
FIG. 1 is a fragmentary partly elevational and partly axial sectional view of the tubular components of the novel hose coupling prior to introduction of the terminal portion of the ri.gid tubular component into the terminal portion of the flexible tubular component;
- 7a -~3 ~
FIG. 2 is a fragmentary axial sectional view of the assembled coupling;
FIG. 3 is a similar fragmentary axial sectional view of a modified fully assembled coupling; and FIG. 4 is a fragmentary axial sectional view of the rigid tubular component and of a tool which is used to shape sealing material prior to introduction of the terminal portion of the rigid tubular component into the flexible tubular component.
FIG. 1 shows one terminal portion 3a of a first tubular component 3 which constitutes a normally flexible hose, and one terminal portion la of a second tubular component 1 which constitutes a ri~id metallic pipe. The terminal portion la;has a free end lb and is provided with a single external annular retainer 2 in the form of a circumferentiallv complete rib. A ring-shaped mass 4 of sealing material surrounds the terminal portion la and is applled at a lacation such that the retainer 2 is located be~ween the mass 4 and the free end lb. The mass 4 consists of a highly viscous hardenable - sealin~ material which preferably exhibits a pronounced tendency to adhere to the metallic material of the terminal portion la while exhibiting a much less pronounced tendency (or ~o tendency at all) to adhere to the material of the terminal portion 3a, In order to assemble the coupling, the terminal portion la is introduced into the terminal portion 3a whereby the latter spreads the material of the mass 4 to convert it into a relatively thin elongated sleeve-like layer 4a ~see FIG. 2) which preferably extends from the _ ~ _ retainer 2 and all the way or substantially all the way to the free end 3b of the terminal portion 3a. The last step o completihg the assemhly of the coupling includes the application of a clamping device 5 (hereinafter called clamp for short) which includes a relatively wide strap 6 with two radially outwardly extending end portions 7 (only one shown in FI~. 2). The end portions 7 are urged toward or against each other by one or more fasteners 8, e.g., a bolt and nut, a screw or the like.
The material of the mass 4 and of the layer 4a is silicon rubber whose sealing characteristics remain at least substantially unchanged within a wide range of temperatures, such as ~ithin the entire range of between approximately -80C and ~260~Cr and at least within the entire range of between -40C and ~140C.- The material of the mass 4 can be a heat-pol~marizable silicon rubber which is vulcanized with peroxides at 200C. ~owever, it is equally possible to employ a cold-vulcaniæable sllicon rubber. A cold vulcaniz-able silicon rubber can constitute a solvent-free p~ste-like twin-component mass with one or more specific cross-linking agents or a single-component mass which is adapted to be cross-linked under the influence of air. In accordance with a presently preferred embodiment, the mass 4 and the layer 4a can consist of dimethyl polysiloxane with cross-linking a~ent and one or more special fillers.
As shown, the tubular component 1 is made of a metallic material. The hose 3 is made of ethylane propylene terpolymer (EPDM) with one or more reinforGing inserts of filamentary material (e.g., a fabric, not shown).
As can be seen in FIG. l, the mass 4 is applied 5f~3 in such ~uantity that it forms a ring having an outer diameter which at least approximates but can exceed the outer diameter of the retainer 2. The material of the mass 4 is tough (highly vlscous), and such material is applled to the external surface of the terminal portion la c].ose to the retainer 2 so that it is located between the retainer and the locus of application of the strap 6 of the clamp 5 when the coupling is fully assembled in a manner as shown in FIG. 2~ As already explained above, the terminal portion 3a of the hose 3 is slipped over the terminal ~ortion la prior to setting of the material of the mass 4. This ensures that the sealing material acts as a lubricant to facilitate application of the hose onto the pipe. Moreover, this entails conversion of the ring-shaped mass 4 into the sleeve-like layer 4a of constant or nearly constant thickness which strongly adheres to the external surface of thé terminal portion la all the way from the retainer 2 to the free end 3b of the terminal portion 3a. Thus, the terminal portion 3a does not or need not contact the terminal portion la between the free end 3b and the top land of the retainer 2. The clamp 5 is applied subseqllent to setting of the material of the la~er 4a, and the fastener or fasteners 8 are tightened to ensure that the internal surface of the strap 6 bears against the external surface of adjacent part of terminal portion 3a so that the latter is urged against the external surface of the sleeve-like layer 4a.
However, it is e~ually within the purview of the invention to apply and tighten the clamp 5 prior to setting of the 3~ sealing material of the layer 4a, 8 ~
FIG. 2 shows that the major part of the layer 4a constitutes a relatively thin film of constant or nearly constant thickness and that the end portion of the layer 4a adjacent the retainer 2 is thicker so that it filIs the annular space between the left-hand flank of the retainer 2 and the adjacent part of internal surface of the terminal portion 3a. When the hardening or setting of the sealing material of the layer 4a is completed, the latter constitutes an elastic sheath or sleeve which strongly adheres to the external surface of the terminal portion la but exhibits a much less pronounced tendency to adhere tor does not adhere at all) to the internal surface o the terminal portion 3a.
The tubular component 1 can constitute a nipple which is rigid with the cooling unit for the engine in a motor ~ehicle. The hose 3 can serve to establish a path for the flow of coolant between the cooler and the engine block. It has been ound that, i the improved coupling is used in a motor vehicle between the cooler and the engine, the material of the terminal portion 3a of the hose 3 contracts in response to coollng (e.g./ in winter while the engine is idle) so that the volume of the terminal portion 3a decreases. In the absence of the la~ter 4a, the terminal portion 3a would become disengaged rom the external surface of the terminal portion la, i.e., the ~ealing action would no longer exist and the terminal portion 3a would he loosely held between the strap 6 of the clamp 5 and the terminal portion la.
However, the layer 4a prevents-~anyleakage of fluid from the interior of the conduit including the pipe 1 and the 2 ~ 8 3 hose 3, even during the interval immediately following startin~ of the engine, i~e~, during the initial stage of pressurization of coolant which flows between the cooler and the engine block ~namely during that stage when the coolant is compelled to flow but is yet to be heated). Such hlghly desirahle sealing action during the just described stage of operation of the engine is attributable to the presence of the layer 4a, particularly of that portion of ~he layer 4a which extends between the clamp 5 and the retainer 2. The reason is that the layer 4a retains its elasticity at low or very low temperatures, namely at those temperatures when the elasticity of the material of the hose 3 is zero or close to zero. Thus, the layer 4a continues to urge the adjacent part of the terminal portion 3a into sealing engagement with the internal surface of the strap 6, and the layer portion between the strap 6 and the retainer 2 continues to exhiblt sufficient elasticit~ to sealingly engage the internal surface of the terminal portion 3a. As the pressure of fluid in the pipe l and hose 3 rises, the elastic layer 4a undergoes radial expansion so that the sealing actiQn of this layer between the retainer 2 and the strap 6- increases with rising pressure of the confined fluid. Since the thickness of the layer 4a is normally more pronounced in the region between the clamp 5 and the retainer 2, such porti~n of the layer furnishes a highly satisfactory sealing action which prevents lea~age of confined fluid at temperatures at which the coupling would be incapable of confining the fluid if the layer 4a were omitted.
As the tem~erature of the coniined fluid rises, the temperature of the coupling also rises~ i.e., the material of the terminal portion 3a expands and the sealing action in the region of the clamp 5 becomes even more satisfactory. This prevents leakage of confined fluid even if the pressure of such fluid rises sufficiently to cause the terminal portion 3a to expand radially outwardly so that it is disengaged from the terminal portion la in the region to the right of the retainer 2, at the retainer 2 and/or between the retainer 2 and the clamp 5.
An important advantage of a sealing material which is highly viscous during application of the mass 4 is that such material can fill any and all depressions (such as axially, circumferentially and/or otherwise oriented grooves, blind holes and the like) in the external surface of the terminal portion la during conversion into the sleeve-like layer 4a of FIG. 2. Thus, it is not necessary to treat the external surface of the terminal portion la to a high degree of precision finish ~(in fact, it is not even necessary to remove ~urrs) because any and aLl unevennesses are compensated for by the material of the mass 4 which fills such unevennesses during conversion into the elongated sleeve-like layer 4a of FIG. 2. Since the material of the sleeve-like layer 4a adheres to the material of the terminal portion la, fluid which is confined in the tubular components 1 and 3 cannot escape between the layer 4a and the terminal portion Ia even if the temperature of the improved coupling is reduced well below the freezing point, e.g., all the way to -80C.
$ ~
It will be noted that the sleeve like layer 4a enhances khe sealing action in the region within the strap 6 of the clamp 5 as well as at both sides of such strap, especially between the strap and the retainer 2. The sealing action of that portion of the layer 4a which is located between the strap 6 and the retainer 2 is independent of the sealing action of the other portion of such layer. This is desirable and advantageous for the aforediscussed reasons, i.e., the layer 4a ensures the establishment of a satisfactory sealing action when the temperature of the terminal portion 3a of the hose 3 is so low that the sealing action between the hose and the strap 6 i5 negligible or nil. At such time, the preferably ; elastomeric layer 4a ensures the establishment of a reliable sealing action in the region between the strap 6 and the retainer 2. That portion of the layer 4a which extends between the retainer 2 and the strap 6 compensates for shrinkage of the sur~rounding part of the terminal portion 3a and prevents leakag@ of confined fluid even if the pressure of such fluid happens to rise while the - temperature of the terminal portion 3a is well below O~C, e.g., at -40~C~ Under such circumstances, the material of the layer 4a between the retainer 2 an~ the strap 6 acts not unllke a radially inward extension of the surrounding part of the terminal portion 3a and enables the coupling to prevent leakage of confined fluid at temperatures which are much too low for the establishment of a satisfactory sealing action by resorting to heretofore known hose couplings.
The layer 4a is equally useful when the temperature 2 ~ 3 of or at the coupling rises well above 0C, e.g., to 90C or higher. Thus, the material of the laver 4a tends to expand within the confines of the strap 6 (such tendency is shared by the m~terial of the termi~al portion 3a) so that the sealing action in the region of the clamp 5 is highly satisfactory. In addition, the material of the Iayer 4a tends to expand in the region between the strap 6 and the retainer 2 so that the sealing action of the coupling is enhanced between the clamp 5 and the free end Ib of the terminal portion la.
Though it is possible to employ a sleeve-like layer 4a which is not elastic at all or exhibits a minimal amount of elasticity, an elastic layer is preferred at this time because such layer constitutes a highly effective barrier against leakage of fluid from the interior of the pipe 1 and hose 3 toward and out-wardly beyond the clamp 5. Thus~ if the pressure of confined fluid rises, suc~ fluid might be capable of flowing around the retainer 2 and of acting upon the material of the layer 4a between the retainer 2 and the strap 6. The elas~ic material of the layer 4a yields radially inwardly and outwardly to bear against the internal surface of the terminal portion 3a and against the external surface of the terminal portion la with the result that it reliably prevents leakage of pressurized fluid all the way to the strap 6. If the pressure of confined fluid decreases, the thickness of the layer 4a between the retainer 2 and the strap 6 also increases to thus enhance the sealing action in a different way. If some elastic material of the la~er 4a was expelled from 2 ~ 3 the r~gion at the left-hand flank of the retainer 2 (as viewed in FIG. 2), such material returns due to elasticity of the layer 4a and this ensures that the space at the left-hand flank of the retainer 2 is filled with elastic sealing material to ensure the establishment of a reliable sealing action.
An advanta~e of the feature that the material of the layer 4a does not tend to adhere to the terminal portion 3a is that the terminal portion 3a can be more readily slipped onto the layer 4a prior to application of the clamp 5. In addition, the terminal portion la and its sleeve-like layer 4a can be more readily extracted from the terminal portion 3a as soon as the clamp 5 is removed or loosened.
Since the layer ~a preferably extends all the way to the free end 3b of the terminal portion 3a, the terminal portion la can be readily extracted from the hose 3, as soon as the clamp 5 is removed or loosened, because the terminal portion 3a cannot contact the terminal portion la (excep~ perhaps in the narrow region between the top land of the retainer 2 and the free end lb). This is desirable and advantageous because the terminal portion 3a would normally tend to adhere to the termi~al portion la after a relatively long intervàI of application of the clamp S. The mass 4 acts not unlike a body of lubricant during initial application of the terminal portion 3a over the terminal portion la to thus ensure that the terminal portion la can be introduced into the hose with a minimum of effort; at such time, the terminal portion 3a spreads the material of the mass 4 over the external surface of the terminal portion la to thus convert the mass into the sleeve-like layer 4a.
A sealing material which exhibits a preferably pronounced tendency to adhere to the (metallic or plastic) material of the terminal portion la exhibits the additional advantage that the likelihood of leakage of pressurized fluid from its path in the pipe 1 and hose 3 into the surrounding atmosphere by flowing directly along -the external surface of the terminal portion la is practically nil. Once the material of the layer 4a sets, this layer can be considered an inte~ral part of the terminal portion la with attendant advantages as regards the combined sealing action of the parts la and 4a.
Furthermore, the layer 4a then compensates for eventual unevennesses in the external surface of the terminal portion la even if the latter was not subjected to any finishing or precision finishing treatment such as removal of scale, deburring, polishing, grinding and the like.
It has been found that the sealing action of the impro~ed coupling is highly satisfactory if the terminal portion la is made of a metallic or plastic material (..i~ the latter instance preferably a polyamide), if the terminal portion 3a of the hose is made of .silicon ruhber or EPDM, and if the layer 4a consists of synthetic rubber or a fluoroelastomer.
It has also been found that the terminal portion 3a is capable of converting the mass 4 into a suhstantially uniform layer 4a (without pushing a substantial percentage of the material of the mass 4 in front of its free end 3b) during insertion of the terminal portion la into the hose 3. This is believed to be attrihutable to the selection of a highly viscous sealing material which acts as a lubricant whiIe it is being converted into a sleeve-like layer that preferably extends all the way from the top land of the retainer 2 to the free end 3b.
FI~. 3 shows a portion of a modified coupling.
The difference between the couplings of FIGS. 2 and 3 is that the metallic component li includes a terminal portion la' with two ~eighboring circumferentially extending annular external retainers 2 one of which is adjacent the free end lb' and the other of which is located betw~en the one retainer and the strap 6 of the clamp 5. The mass of highly viscous sealing material which is applied to the exterior of the terminal portion la'- includes a first section 4~ in the annular depression or valley between the retainers 2 and a second sec~ion which is converted into the sleeve-like layer or film 4a' in response to introduction of the t~rm.inal portion la' into the terminal portion 3a of the hose 3.
The arrangement may be such that the mass of sealing material is applied only in the valley between the two retainers 2 but in such guantity that a certain percentage of such mass is entrained by the internal surface of the.terminal portion 3a while the latter is being slipped onto the terminal portion la' (or while the terminal portion la' is in the process of being lntroduced into the terminal portion 3a) so that the thus separated portion of the mass 4' hetween the retainers 2 forms the sleeve-like layer or film 4a'. In other words, the valley 2 ~
or groove ~etween the two retainers 2 can serve primarily as a receptacle for that portion of the (originally much larger) mass 4' whlch is not converted into the layer 4a'.
This is often desira~le and advantageous because the provision of a receptacle for surplus sealing material ensures that the surplus cannot penetrate into the interior of the conduit (i.e., beyond the free end lb' of the terminal portion la 7 ) during introduction of the terminal portion la' into the terminal portion 3a. In addition, the sealing material which remains between the retainers 2 contributes to the establishment of an even more satisfactory and more reliable sealing action within the desired temperature range.
FIG. 4 shows a substantially cylindrical shaping or spreading tool 9 which can be utilized to convert one or more streams or flows of sealing material into a layer 4a even before the terminal portion la of the tubular component 1 is introduced into the terminal portion 3a (not shown in FIG. 4) of the hose 3. The internal surface of the shapihg or spreading tool 9 is configurated in such a way that it is complementary to the desired external surface of the layer 4a. The internal surface is provided with annular boundaries 10 and 11 at the axial ends of the layer 4a. The tool 9 is preferably assembled of two or more shells or sections which have abutting radially and axially extending surfaces and permit rapid application of the tool over, as well as rapid disengagement of the tool from, the terminal portion la of the pi~e 1.
The internal surface of the tool 9 is preferably coated with a layer of material (indicated by the legend "FILM"~ which does not adhere to the material of the layer 4a to thus permit rapid separation of the tool from the finished layer 4a. The material of such layer can be permitted to set prior to or after insertion of the terminal portion la into the termlnal portion 3a of a hose 3. The arranyement is preferahly such that, when the tool 9 is properlv applied over the terminal portion la, a re~uisite amount of highly viscous sealing material is admitted into the annular space between the tool and the terminal portion la so that the injected material fills the annular space and forms the layer 4a. In other words, if one employs the tool 9 or an analogous tool, the application of a mass 4 can be dispensed with because one or more streams or flows of injected sealing material can be directly converted into a sleeve-like layer 4a which is ready to be surrounded by the terminal portion of a hose. An opening or inlet for admission of flowable sealing material into the space between the tool 9 and the terminal portion la is shown b~ broken lines~ as at 13.
The tool 9 can be provided with one~ two or more openings or inlets for admission of sealing material.
An advantage of the tool 9 and of the method which was described with reference to FIG.4 is that the la~er 4a can be formed in advance, e.g., in the plant which makes the coolers for the engines of motor vehicles.
This renders it possible to more rapidly assemble the hose 3 with the terminal portion la of FIG. 4 because the latter already carries a inished layer 4a which is ready to enter the terminal portion of the hose prior to - 20 ~
application of the clamp 5 or another suitable clamp (or two or more clamps). Application of the sleeve-like layer 4a to the terminal portion la prior to assembling the ~ubular component 1 with another tubular component (such as the hose 3 of FIGS. 1 to 3) is desirable and advantageous in many instances, for example~ if the hose 3 is to be connec~ed to a nipple (1) of a water pump in a motor vehicle.
The tubular component 1 can constitute a length of pipe which has two terminal portions each of which is provided with one or more external retainers 2. This enables such tubular component to be used as an element of a coupling between two flexible hoses or the like, i.e., each terminal portion of the just described tubular component with two terminal portions (each having at lea.st one retainer 2 or an analogous retainer3 can be introduced into a discrete hose.
The tubular component 1 can also be made of a rigid or praatically rigid plastic or other material (e.g., polyamide), i.e., it is not always necessary to couple the hose 3 to a metallic pipe. Furthermore, the hose 3 (or at least the terminal portion 3a of this hose3 can be made of the same material as the mass 4, e.g., silicon ru~ber, and is ~preferably provided with one or more reinforcing inserts of filamentary material or the like~ e.g., with one or more reinrorcing inserts of textile material. Still further, the sleeve-like layer can be made of any one of a variety of different materials including ~ynthetic ru~ber and many others, e.g., a fluoroelastomer. Suitable elastomers are those known as ~ ~ ~r~ r~
TEFLON (Trademark) and VITON (Trademark) which are made and sold by DuPont.
'
Claims (24)
1. A coupling comprising a first tubular component having a deformable first terminal portion;
a second tubular component having a second terminal portion provided with at least one external retainer and received in the first terminal portion; and a substantially sleeve-like layer between said terminal portions, said layer consisting of a sealing material whose sealing characteristics remain at least substantially intact at temperatures within an entire range of between approximately +260°C and -80°C.
a second tubular component having a second terminal portion provided with at least one external retainer and received in the first terminal portion; and a substantially sleeve-like layer between said terminal portions, said layer consisting of a sealing material whose sealing characteristics remain at least substantially intact at temperatures within an entire range of between approximately +260°C and -80°C.
2. The coupling of claim 1, further comprising a clamp surrounding said first terminal portion, said second terminal portion having a free end and said at least one retainer being disposed between said free end and said clamp.
3. The coupling of claim 1, wherein said layer is elastic.
4. The coupling of claim 1, wherein said first terminal portion consists of a material which does not exhibit a tendency to adhere to the sealing material of said layer.
5. The coupling of claim 1, wherein said first terminal portion has a free end and said layer extends from said free end to said at least one retainer.
6. The coupling of claim 1, wherein said sealing material adheres to said second terminal portion.
7. The coupling of claim 1, wherein said sealing material is a hardened originally highly viscous substance.
8. The coupling of claim 1, wherein said first terminal portion consists of a material selected from the group consisting of EPDM and silicon rubber.
9. The coupling of claim 8, wherein said first terminal portion contains at least one reinforcing layer of filamentary material.
10. The coupling of claim 1, wherein said second terminal portion consists of a metallic material.
11. The coupling of claim 1, wherein said second terminal portion consists of a plastic material.
12. The coupling of claim 11, wherein said plastic material is polyamide.
13. The coupling of claim 1, wherein said sealing material is selected from the group consisting of synthetic rubber and fluoroelastomers.
14. The coupling of claim 13, wherein said synthetic rubber is silicon rubber.
15. A method of establishing a sealing connection between a first tubular component having a deformable first terminal portion and a second tubular component having a second terminal portion provided with at least one external retainer and having an open end adjacent said at least one retainer, comprising the steps of applying around the second terminal portion a mass of hardenable viscous sealing material whose sealing characteristics remain at least substantially unchanged within an entire range of between at least -40°C and +140°C so that the at least one retainer is located between the mass and the open end of the second terminal portion; and introducing the second terminal portion into the first terminal portion.
16. The method of claim 15, wherein said introducing step is carried out prior to hardening of the material of said mass.
17. The method of claim 15, further comprising the step of converting the mass into a layer prior to hardening of the material of the mass, said introducing step being carried out subsequent to said converting step and subsequent to hardening of the material of said layer.
18. The method of claim 15, wherein said material is selected from the group consisting of synthetic rubber and fluoroelastomers.
19. The method of claim 18, wherein said synthetic rubber is silicon rubber.
20. The method of claim 18, wherein said first terminal portion consists of a material which is selected from the group consisting of EPDM and silicon rubber.
21. A method of establishing a sealing connection between a first tubular component having a deformable first terminal portion and a second tubular component having a second terminal portion provided with at least one external retainer and having a free end, comprising the steps of establishing an annular space around the second terminal portion so that the at least one retainer is located between the space and the free end; introducing into the space a hardenable viscous sealing material having sealing characteristics which remain at least substantially intact at temperatures within an entire range of between at least +140°C and -40°C so that the introduced material forms a substantially tubular layer; and inserting the at least one retainer, the layer and the second terminal portion into the first terminal portion.
22. The method of claim 21, wherein said establishing step includes placing a tubular tool around the second terminal portion and further comprising the step of removing the tool prior to said inserting step.
23. The method of claim 21, further comprising the step of causing or permitting the sealing material to set prior to said inserting step.
24. The method of claim 21, wherein the first terminal portion contains a material which is selected from the group consisting of EPDM and silicon rubber, said second terminal portion contains a metallic or plastic material, and said sealing material is selected from the group consisting of silicon rubber and fluoroelastomers.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4039054 | 1990-12-07 | ||
| DE4039054A DE4039054C1 (en) | 1990-12-07 | 1990-12-07 | Tube-pipe connection - includes holding rib at end of pipe and securing ring, which is placed over tube behind rib section |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2056583A1 true CA2056583A1 (en) | 1992-06-08 |
Family
ID=6419793
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002056583A Abandoned CA2056583A1 (en) | 1990-12-07 | 1991-11-28 | Hose coupling and method of making the same |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPH04290696A (en) |
| CA (1) | CA2056583A1 (en) |
| DE (1) | DE4039054C1 (en) |
| FR (1) | FR2670267B1 (en) |
| GB (1) | GB2250557B (en) |
| IT (1) | IT1250354B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997013093A1 (en) * | 1995-10-06 | 1997-04-10 | Tokai Rubber Industries, Ltd. | Hose with securing layer and connecting structure therefor |
| JP2010051378A (en) * | 2008-08-26 | 2010-03-11 | Daikin Ind Ltd | Connection tube |
| DE102012217147A1 (en) * | 2012-09-24 | 2014-04-17 | Witzenmann Gmbh | Connector for spiral corrugated hose used in e.g. exhaust gas return system of vehicle, has sealing element that is partially provided in threaded portion of internal and external screw threads |
| DE102018212593A1 (en) | 2018-04-23 | 2019-10-24 | Aft Automotive Gmbh | Fluid connection adapter, fluid connection assembly, and method of making a fluid connection adapter |
| DE102018208508A1 (en) | 2018-05-29 | 2019-12-05 | Aft Automotive Gmbh | Fluid connection adapter, fluid connection assembly, and method of making a fluid connection assembly |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1951368U (en) * | 1963-09-04 | 1966-12-08 | Daimler Benz Ag | HOSE FITTING FOR HIGH PRESSURE HOSES. |
| DE1212798B (en) * | 1963-09-04 | 1966-03-17 | Daimler Benz Ag | Hose fitting for high pressure hoses and method for assembling the same |
| GB1245829A (en) * | 1968-01-19 | 1971-09-08 | Mitsui Petrochemical Ind | Improvements in or relating to pipe joint devices |
| DE2926568A1 (en) * | 1979-06-30 | 1981-01-22 | Hoechst Ag | METHOD FOR PRODUCING HYDROPHILATED GRAFT POLYMERISATS FROM PROTEINS AND THE USE THEREOF |
| GB2177769B (en) * | 1985-07-17 | 1989-07-26 | Guest John D | Improvements in or relating to hose connectors |
| US4643465A (en) * | 1985-08-23 | 1987-02-17 | Corning Glass Works | Pipe coupling |
| US4660867A (en) * | 1986-04-22 | 1987-04-28 | The Gates Rubber Company | Coupled hose assembly |
-
1990
- 1990-12-07 DE DE4039054A patent/DE4039054C1/en not_active Expired - Lifetime
-
1991
- 1991-10-18 GB GB9122265A patent/GB2250557B/en not_active Expired - Fee Related
- 1991-11-28 CA CA002056583A patent/CA2056583A1/en not_active Abandoned
- 1991-12-02 JP JP3341711A patent/JPH04290696A/en active Pending
- 1991-12-06 FR FR919115157A patent/FR2670267B1/en not_active Expired - Fee Related
- 1991-12-06 IT ITTO910945A patent/IT1250354B/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| FR2670267A1 (en) | 1992-06-12 |
| GB2250557B (en) | 1994-06-01 |
| IT1250354B (en) | 1995-04-07 |
| FR2670267B1 (en) | 1994-10-21 |
| GB2250557A (en) | 1992-06-10 |
| ITTO910945A1 (en) | 1992-06-08 |
| ITTO910945A0 (en) | 1991-12-06 |
| DE4039054C1 (en) | 1992-05-21 |
| GB9122265D0 (en) | 1991-12-04 |
| JPH04290696A (en) | 1992-10-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |