DE4432735A1 - Method and device for producing connecting hoses and hose produced therewith - Google Patents

Abstract

An extruder device (D) produces hoses (T, Figure 2) having portions (P) of increased thickness for protective purposes, for installation in the engine compartments of vehicles. This device (D) comprises movable obturators (5), the positions of which define the outside diameter of the hose (T). With the obturators in the position 5b (see dotted lines) the external diameter of the extruded hose is smaller than when the obturators are in the position 5a. When the obturators are in the position 5b, material may also be extruded through apertures 6 so as to prevent increase in pressure within the extruder. Several embodiments of obturators are disclosed. <IMAGE>

Description

The invention relates generally to devices for manufacturing of hoses and more specifically a device as well as a Process for making rubber hoses for installation in engine compartments of motor vehicles. Another item The invention is a hose made with it.

As is known, there is also in the engine compartment of a motor vehicle Internal combustion engine numerous connection hoses, as with for example, the hoses for the cooling, the fuel and the lubricant circuit.

These hoses are typically made of plastic or Made of elastomer material, for example made of rubber. she can be reinforced, d. H. you can put one in the hose Wall inserted fabric layer and are more normal produced by extrusion. After extrusion the hose, which is still plastic and defor at this stage mable is shaped, d. H. bent to make the one you want Takes shape. Once it is molded, the tube will be treated to make it elastic, so that it made it elastic retained shape. For example, rubber hoses are vulcanized.

There is a tendency, especially recently, to the outside dimensions of motor vehicles and especially of cars in to reduce to an ever greater extent and thereby the interior comfort to keep unchanged or even improve. This u. a. reduces the available space for the engine compartment Room.

As a result, the space in the engine compartment becomes almost complete from the engine and the other mechanical parts contained therein len ingested. Therefore, the one for the connecting hoses available space is becoming less and less Hoses need to be molded, sometimes with twisted ones Profiles and very small radii of curvature so that they fit into the available spaces and paths fit.  

They are therefore very close to or in contact with the Engine and other mechanical parts. Because strong vibrations generated when the vehicle is in motion or when the machine is running, the hoses can rub against the mechanical parts are damaged or worn. Some these parts, such as the engine and exhaust manifolds, are very hot; the vibrations can close those parts len running hoses closer to or in contact bring or can bring hoses that are already in Contact with them, wear out.

The hoses therefore need protection if they are the pre named risks of damage are exposed.

It is known in the prior art to protect the hoses hoses or jackets, which are also made of plastic or Elastomeric materials such as EPDM, PVC, polyols resin, neoprene, etc., are made to adapt to the exposed areas of the hose from heat or abrasion protect.

For a better understanding Fig. 1 shows a connecting hose T made of reinforced rubber C, on which a protective sleeve P is attached. However, this protection technique has several disadvantages.

The process of placing a cuff over the tube is quite difficult since connection hoses, like already found increasingly twisted shapes and ever narrower crumbs radii and also because the protective jacket is tight to be attached so that it no longer moves, so as soon as it is in the desired location.

To do this, it is typically necessary to straighten the hose, for example by moving in a straight metal pipe brings him in before the protection hose can be put on. If the protective coat continues to make it easier to attach, it is  then necessary to fi fi it at the desired location xieren, for example by means of adhesive or a clamp direction, which is an additional operation and brings additional costs.

The invention has for its object a device and to provide a method of making hoses, the above problems in satisfactory solve the wise.

According to the invention, this object is achieved by means of a Vorrich tion and a method with the in the claims, which connect to the description, listed features Fulfills.

Other advantages and features of the invention will become apparent from the following detailed description it will become clear which che with the help of the attached, just not restricting exemplary embodiments drawings given is. They represent:

Fig. 1 a connecting tube with a protective device according to the prior art, as has already been described,

Fig. 2 is a connection tube provided with the inventive device forth

Fig. 3 shows a known apparatus schematic for the manufacture of hoses,

Fig. 4 schematically shows a device according to the invention for the manufacture of hoses,

Fig. 5 shows schematically an alternative embodiment of the on direction of FIGS. 4 and

Fig. 6 shows schematically a further alternative embodiment of the device of FIG. 4.

The invention essentially includes a device for Manufacture of connecting hoses with differentiated walls Strength. The device enables the aforementioned Manufacture tubing in a single extrusion step.

For a better understanding, a known device for extruding reinforced rubber hoses will first be described with reference to FIG. 3. The device 1 has an inlet 2 through which rubber G is inserted in the plastic state. A rubber tube TC is inserted from a second inlet located in the rear area 3 of the device 1 , also in the plastic state and covered by a fabric layer or matrix C. In the front section of the device 1 there is an annular opening 4, which is called the extrusion opening below. In the device 1 , the rubber G is subjected to pressure in order to let it emerge from the extrusion opening 4 .

The ring shape of the opening 4 leads to the extrusion of a cylindrical rubber hose. The outer diameter of the extrusion opening 4 defines the size of the extruded tube and the diameter of a central body 8 consequently determines the wall thickness of the extruded tube via the difference.

The fabric layer C is in the wall of the extruded tube inserted.

After the reinforced rubber hose has been extruded, it is cut to the desired lengths to connect manufacture hoses. The one cut in this way Hose parts are given the desired shape, such as be already set out. The final step in the process is Vulcanize the tubing so that the rubber G from which it is made are formed from the plastic state to the elastic State passes; in this way the hoses can keep the shapes they have been given.  

Fig. 4 shows the front part of an extruder device D according to the invention. The following description relates in principle to those features by which the device D differs from the known device 1 .

The device D also comprises an extrusion opening 4 (hatched in the drawing for greater clarity) which, like the known device 1, is ring-shaped. However, this opening 4 has a considerably larger outer diameter than the opening 4 of the known device 1 for further predetermined features of the hose to be produced. More specifically, the opening 4 is of such a size as to produce a hose with a wall thickness which is substantially the same as the thickness of the normal hose plus the thickness of a protective jacket to be attached to the hose.

The front part of the device D, and more particularly the flat front, which contains the extrusion opening 4 , has two movable jaws or locking elements 5 . The two locking elements 5 are movable in the directions indicated by the double arrows 7 parallel to the front. In the drawing, they are shown in continuous outline in the positions 5 a withdrawn and in dashed outline in the positions 5 b advanced. As can be seen, those sections of the two locking elements 5 which point towards the extrusion opening 4 have semicircular, concave profiles.

In practice, when the two locking elements 5 have been brought close together, they reduce the outer diameter of the extrusion opening 4 . In the advanced position 5 b be limit the two locking elements 5 an extrusion orifice 4 with a wall thickness which is smaller than the wall thickness of the extrusion opening 4 when the latter is not restricted by the locking elements 5 together with the Zentralkör per 8 namely significantly. The locking elements 5 are of course of such a size that they determine a desired wall thickness of the hose, and more particularly the wall thickness of a normal or unprotected hose.

The device D can therefore clearly be used for the production of connecting hoses of different wall thickness. Namely, it is sufficient, during the extrusion of jenigen portions of the tubing in which it needs no protection to keep the locking element 5 in the advanced positions 5 b and the locking elements 5 for those portions of the tubing in which it needs a protection, in to move the withdrawn positions 5 a.

In some embodiments, which have locking elements 5 and extrusion openings 4 of given shapes, such as, for example, those shown in FIG. 4, the hose produced can have undesirable defects. If the locking elements 5 are namely in a position between the advanced position 5 b and the retracted position 5 a, projections or ribs are formed on the outer side of the extruded tube. These projections or rips are undesirable.

An embodiment of the device according to the invention will now be described, which can extrude a hose with a uniform surface without ribs. In Fig. 5, in which only the area of the extrusion opening in question is represented, 4 beschrie bene parts and elements already described with reference to FIG. Again provided with the same reference numerals and / or letters. As can be seen from Fig. 5, the hatched extrusion opening 4 is not ringför shaped, but has on its outer edge three projections 9 which point towards the central body 8 .

These below wedges projections 9 are tapered and of such a length that they are spaced from the central body 8 by a distance which is equal to the desired thickness of the normal or unprotected wall of the hose. In this embodiment, three Sperrele elements 5 are present, each of which therefore touches a 120 ° section of the extrusion opening 4 . Otherwise, the locking elements 5 are the corresponding elements 5 in Fig. Sperrele shown 5 substantially similar.

The locking elements 5 are of such a size that they extend into the advanced positions 5 b as far as the wedges 9 into the ex trusion opening 4 and, as can be seen from the drawing, define a circular extrusion opening with reduced wall thickness. The normal or unprotected hose is of course extruded in this state. If it is necessary to extrude a protected hose section, the locking elements 5 are moved into the retracted positions 5 a. As can be seen, the extruded tube in these positions has the larger diameter desired for the protected tube sections and defined by the unlocked extrusion opening 4 . Clearly, the extruded tube in these sections does not have a continuous cylindrical surface, but has three grooves, which are caused by the wedges 9 and are parallel to its axis. However, since these grooves are of very limited width or radial size, they do not adversely affect the advantages conferred by the increased strength of the hose for protection purposes. This method achieves the advantage of completely removing unwanted ribs or protrusions. In the intermediate or transition tube sections there is a gradual transition from the smaller diameter to the larger diameter of the extruded tube, while the grooves, which are initially missing, gradually become deeper.

The steps below are exactly the same as those that described above with reference to the prior art were. The extruded tube is then cut molded and then vulcanized. The invention can of course also used to make hoses extruding materials other than rubber, for example the above in the description of the prior art led materials.  

FIG. 2 shows a connecting tube T made of reinforced rubber C using the device D according to the invention. As can be seen, this tube T has a section S which has a wall thickness which is greater than the normal wall thickness of the tube T. It is clear that the effect achieved is identical to that which can be obtained according to the prior art by applying a protective jacket P.

The method according to the invention has in comparison with the prior art technology, however, has some advantages. Since the protective section S is in one piece with the hose T, it is clearly un him possible to move; a disadvantage of the prior art is eliminated in this way. In addition, the fiction according to protected hose T in a fairly simple manner one, the normal verbin extrusion step hoses essentially similar extrusion step manufactured, making the need more difficult and expensive additional protective steps completely eliminated.

According to an alternative embodiment, the device D advantageously has an outlet opening 6 for each blocking element 5 , through which the material D supplied to the device D can be extruded.

It should be noted that during the extrusion process the hose emerging from the extrusion opening is small gig expands immediately after it has been extruded. This expansion is due to the fact that the Extrusion takes place under pressure.

Due to this phenomenon, the extrusion opening 4 is formed with dimensions that are slightly smaller than that of the hose to be produced. Since the blocking elements 5 "clog" the extrusion opening 4 in practice, ie they reduce the area through which the extrusion actually takes place, they cause an increase in the pressure in the device D. Of course, this pressure increase would be the diameter of the extruded tube influencing extrusion conditions undesirably change.

The outlet openings 6 , which are also shown hatched because extruded material G also emerges from them, have the purpose of eliminating this problem. As can be seen from Fig. 4, the two openings 6 are blocked by the locking elements 5 when the latter are in the retracted positions 5 a. When the locking elements 5 are brought into the advanced positions 5 b, they open the holes 6 through which the extruded material G therefore exits.

The openings 6 are of such a size that their surfaces correspond to that surface of the extrusion opening 4 which is blocked by the two locking elements 5 in their advanced positions 5 a. This measure thus leaves the total area through which the extrusion takes place, both when the locking elements 5 are in the retracted positions 5 a, as well as when the locking elements 5 are in the advanced positions 5 b, unchanged .

The pressure in the extruder device D therefore remains constant substantially unchanged; the extrusion is therefore the same moderate and in a controlled manner.

Of course, alternative embodiments of the device D can be formed by changing the number, the arrangement and the shapes of the locking elements 5 . For example, it might be desirable to form a tube with a wall that is thicker only in a portion of its ring cross-section. It is also possible to form hoses with shapes other than cylindrical.

In particular, an alternative embodiment of the invention similar to the embodiment described by way of example with reference to FIG. 4 will now be described with reference to FIG. 6. Such parts and elements of FIG. 6, which have already been described with reference to FIG. 4, are again provided with the same reference letters and / or numbers.

In this case, the described specific embodiment the advantage that it is very easy to implement while they face the problem of the formation of unwanted ribs Eliminated transition phases of extrusion.

As can be seen from Fig. 6, the structure of the extruder device D is substantially similar to that shown in Fig. 4. The difference lies essentially in the shape of the extrusion opening 4 . The extrusion opening 4 has a substantially elliptical or oval outer edge. The inner edge, however, is of a regular shape, ie essentially circular. If the locking elements 5 are in their forward positions 5 b, the extruded tube has a small diameter and a uniform, annular cross section. However, when the locking elements 5 are brought into their retracted positions 5 a, the extruded tube has an increased wall thickness essentially in two diametrically opposite areas of its cross section.

The advancement or retraction of the locking elements 5 obviously does not lead to the formation of undesirable ribs, since the connection between the extrusion opening 4 and the locking elements 5 never leads to jumps or acute angles.

This embodiment thus enables the production of a Hose with increased wall thickness in most of its Cross-section while being a remarkable structural Has simplicity. Of course that means existence protected hose sections in which the wall thickness of the Unprotected tubing thickness essentially the same remains, however, that during bending, i.e. H. the formation the connecting hoses, the orientation of the  Hose to consider, so those parts that are most exposed to the risk of wear during use actually the hose sections with increased strength correspond.

Of course, while maintaining the invention principles of construction details and forms of training in terms of those described and illustrated in a wide range Scope to be changed without departing from the scope of the invention to leave.

An extruder device provides connecting tubes, which have sections of increased thickness for protection purposes; Installation in engine compartments from motor vehicles. This before direction includes two movable locking elements, the position the outer diameter of the hose. she can thus without additional work processes with clear advantages protect the hoses.

Claims (17)

1. extruder device (D) for producing a connec tion hose, in particular for use in motor vehicle internal combustion engines, comprising an essentially union-shaped extrusion opening ( 4 ), characterized in that it comprises locking means ( 5 ) which at least between the first, withdrawn Positions ( 5 a) and two, advanced positions ( 5 b) are movable and allow material (G) in the plastic state through the extrusion opening ( 4 ) in the form of hoses with wall sections which correspond to the positions of the locking means ( 5 ) have different thicknesses to extrude. 2. Device (D) according to claim 1, characterized in that the locking means ( 5 ) can change their positions ( 5 a, sb) accordingly the outer diameter of the device by means of the device (D) extruded hose. 3. Device (D) according to claim 2, characterized in that the locking means ( 5 ) advanced positions ( 5 b), in which the extruded tube has a first outer diameter, and retracted positions ( 5 a), in which the extruded tube has a second outer diameter that is larger than the first outer diameter. 4. The device (D) according to claim 3, characterized in that the locking means on at least one surface of the device (D) in which the extrusion opening ( 4 ) is formed comprise at least two locking elements ( 5 ), the sections of the locking elements (those) 5 ), the extrusion opening ( 4 ) facing, have substantially circular concave profiles. 5. The device (D) according to claim 4, characterized in that the extrusion opening ( 4 ) has an elongated, substantially union elliptical outer profile when the locking elements ( 5 ) are in the retracted positions ( 5 a), the outer profile being a essentially takes on a circular shape when the locking elements ( 5 ) are in the advanced positions ( 5 b). 6. The device (D) according to claim 4, characterized in that the extrusion opening (4) has an outer profile with from cracks (9) which are oriented in the extrusion opening (4) in and located at positions of the extrusion opening (4) to which the locking elements ( 5 ) lie next to each other in the advanced positions ( 5 b). 7. The device (D) according to claim 6, characterized in that the projections ( 9 ) are short and tapered. 8. The device (D) according to claim 7, characterized in that the projections ( 9 ) are substantially trapezoidal. 9. The device (D) according to claim 8, characterized in that the extrusion opening ( 4 ) pointing from sections of the projections ( 9 ) substantially circular ge, concave profiles. 10. The device (D) according to one of claims 6 to 9, characterized in that it comprises three locking elements ( 5 ) and three projections ( 9 ). 11. The device (D) according to any one of the preceding claims, characterized in that the surface for the extrusion of the material (G) little least contains a further opening ( 6 ), said further opening ( 6 ) being arranged in such a way that it is selective, the positions ( 5 a, 5 b) of the locking means ( 5 ) accordingly, blocked and opened. 12. The device (D) according to claim 11, characterized in that the further opening ( 6 ) and the locking means ( 5 ) are arranged and designed in such a way that when the locking elements are in the advanced positions ( 5 b) are located, open the further opening ( 6 ) and then, when the locking means ( 5 ) are in the retracted positions ( 5 a), block the further opening ( 6 ). 13. The device (D) according to claim 12, characterized in that the further opening ( 6 ) and the locking means ( 5 ) are arranged and designed in such a way that the combined surfaces of the extrusion opening ( 4 ) and the further opening ( 6 ) through which the material (G) is extruded through the substantially lead-ben unchanged when the locking means (5) in the advanced and retracted positions (5 b a, 5) are located. 14. Device (D) according to one of claims 11 to 13, characterized in that the further opening ( 6 ) and the locking means ( 5 ) are arranged and designed in such a way that the pressure of the material (G) in the device ( D) remains essentially unchanged during an extrusion process, regardless of the positions ( 5 a, 5 b) assumed by the blocking means ( 5 ). 15. The device (D) according to claim 14, characterized in that it has a further opening ( 6 ) associated with each locking element ( 5 ). 16. A method for extruding by means of an extruder device (D) according to one of claims 1 to 15 extruded tubes with different wall thicknesses, characterized in that it comprises the following steps:

• - Holding the locking means in the advanced positions ( 5 b) for those sections of the hose in which this should have a first wall thickness,
• - Holding the locking means in the retracted positions ( 5 a) for those sections of the hose in which this should have a second wall thickness which is greater than the first thickness.

17. Connection hose with sections of different Wall thicknesses for use in automotive burning engines manufactured by the process of Claim 16.