US2525619A - Pump - Google Patents
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- US2525619A US2525619A US728258A US72825847A US2525619A US 2525619 A US2525619 A US 2525619A US 728258 A US728258 A US 728258A US 72825847 A US72825847 A US 72825847A US 2525619 A US2525619 A US 2525619A
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- Prior art keywords
- pump
- rotor
- chamber
- liner
- face
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/30—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
- F04C2/34—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members
- F04C2/344—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member
- F04C2/3441—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member the inner and outer member being in contact along one line or continuous surface substantially parallel to the axis of rotation
Definitions
- This invention relates to pumps and particularly to rotary vane type pumps.
- an eiilcient, inexpensive rotary vane type pump is so constructed and arranged that it can operate in a clockwise direction or in a counter-clockwise direction, can be inexpensively formed without heretoforenecessary machining operations, has a suction drained seal chamber, is non-pulsating. and is relatively free from liner wear.
- the rotor for the pump has integral shaft portions projecting from opposite side faces thereof and has vanereceiving slots at spaced intervals around the periphery thereof and extending through the side faces thereof so that they are cheaply formed by a shaper, a grinder, or a milling cutter.
- These vane slots have solid bottoms and the bottoms of diametrically opposed slots are connected through drilled holes. Pins slidably ride in these holes and act on the inner ends of the vanes to maintain the vanes in contact with the pump liner.
- the vanes preferably have rounded outer ends for riding on the pump liner and grooves on one side face thereof to vent the inner ends of the rotor slots to the pumping chamber between the rotor and liner.
- the vanes are reversible to have their grooved faces on either side. If the grooves are on the trailing sides of the vanes,
- the inner ends of the vanes are only subject to negative inlet pressures and the thrust on the vanes due to discharge pressure acting on their rounded outer ends is inward to subtract from the centrifugal force tending to hold the vanes tightly against the liner. If the grooves are on the leading sides of the vanes, the inner ends of the vanes are exposed to discharge pressure and the outer ends of the vanes will be forced against the pump liner to add to the centrifugal force. 'Pulsations due to vane retractions are eliminated because fluid trapped behind the vanes is released to occupy the space in the pumping chamber which was previously occupied by the extended ends of the vanes.
- a feature of the invention resides in the provision of bearing blocks which rotatably mount the rotor shaft portions and also provide thrust bearings for the opposite side faces of the rotor to close the open ends of the rotor slots.
- a further feature resides in the provision of a sealed chamber through which the pump rotor shaft projects and which is selectively drained into the port functioning as the inlet port of the pump as determined by the direction of operation of operation of the pump.
- Another feature resides in the provision of a locking pin arrangement for the pump bearing blocks which permits shifting of one of the blocks to'connect the sealed chamber selectively with ports on opposite sides of the pump.
- an object of this invention to provide a vane type pump with a peripherally slotted rotor wherein the slots have closed bottoms and open ends and wherein the closed bottoms of opposed slots are connected by holes for receivmg pms.
- a further object of the invention is to provide an inexpensive rotary vane pump with a rotor having integral shafts projecting from opposite faces thereof and equipped with peripheral slots extending through said faces whereby bearing blocks on the shaft portions afford thrust bearings for the opposite faces of the rotor as well as radial bearings for the shaft portions.
- a further object of the invention is to provide a closed bottomed slotted rotor for pumps with pins connecting opposed rotor slots for acting on the inner ends of vanes therein.
- a still further object of the invention is to provide a pump with a shiftable ported bearing block adapted to selectively connect a seal chamber of the pump with a port of the pump.
- a still further object of the invention is to provide a rotory vane pump having closed bottom vane slots in the rotor thereof slidably receiving vanes with rounded outer ends riding on the bore of the pump liner wherein one side face of the vanes is grooved to vent' the inner ends of the closed bottom slots with the pumping chamber on either the inlet or discharge side of the chamber to control the force pump liner.
- Another object of the invention is to'block off opposed rotor slots in a rotary vane pump and balance the pressure on the blades of the pump by means of relief grooves for eliminating severe liner wear heretofore encountered on the inlet side of a pump by discharge pressure action on through-rotor vanes.
- Figure 1 is a front end elevational view pump of this invention.
- Figure 2 is a side elevational view of the pump.
- Figures is a longitudinal vertical cross-secof the of seating the vanes on the tional view taken along the line III-411 of Figure 1.
- Figure 4 is a transverse vertical cross-sectional view with parts in end elevation taken along the line IV-IV of Figure 2.
- Figure 5 is a fragmentary transverse cross-sec- -tional view taken along the line V--V of Figure 3 and illustrating the position of the bearing block for connecting the sealing chamber of the pump with an inlet port on one side of the pump.
- Figure 6 is a view similar to Figure 5 but illustrating the position of the bearing block for connecting the sealing chamber with an inlet port on the other side of the pump.
- Figure 7 is an enlarged side elevational view, with parts in vertical cross section, of the rotor and shaft unit for the pump of the invention.
- Figure 8 is an end elevational view of the shaft and rotor unit'bf Figure 7.
- Figure 9 is an outer end elevational view of a vane for the pump.
- Figure 10 is a side elevational view of the grooved side of the vane.
- Figure. 11 is an enlarged vertical cross-sectional view of the shiftable bearing block for the pump.
- Figure 12 is a diagrammatic fragmentary view illustrating forces on the vane when the grooved face thereof'is on the leading side of the vane.
- Figure 13 is a view similar to Figure 12 but illustrating the forces on the vane when the grooved face of the vane is on the trailing side.
- the ump I shown in Figures 1 to 4 has a casing I I with a generally cylindrical portion I la extendin to a radial flange IIb and a rounded cylindrical nose IIc projecting from the central portion of the opposite face of the flange.
- the casing II has a cylindrical bore I2 extending inwardly from the rear face thereof through the portion Ila to a shoulder I3.
- a smaller diameter bore I4 extends from the inner end of the shoulder I3 through the portion I I0 of the housing to a shoulder I5.
- a still smaller diameter bore I6 extends from the shoulder I through the front end face of the housing portion Ilc.
- a groove I1 is formed in the bore I2 adjacent the rear end face of the portion Ila of the casing.
- the casing as best shown in Figures 2 and 4, has bosses I Id and He extending radially outward from the casing portion Ila and terminating flush with the outer face of the flange IIb. These bosses I Id and I Ie provide ports 8 and 9 which extend radially through the bosses and communicate at their inner ends with recesses 8a and 9a respectively formed in the bore I2 and having the configuration shown in Figure 2.
- these recesses 8a and 9a communicate with the pumping chamber of the pump.
- the pump includes a unitary shaft and rotor I8, a seal assembly I9, a front end bearing block 20, a liner 2
- the shaft and rotor unit I8' includes an elongated shaft portion IBa, a larger diameter circular block portion I81), and a shorter shaft portion I80.
- the shaft portions I8a and I80 are in axial alignment.
- the outer end of the shaft portion I8a has a key slot 29 therein for coupling with a driver (not shown).
- the block portion I8b constitutes a rotor for the pump and has a circular outer periphery 30 of materially larger diameter than the shafts I8a. and I8c together with flat side faces including a front side face 3
- Radial slots 33 extend inwardly from the periphery 30 and are cut through the side faces 3
- the slots 33 are easily out since they extend through the faces 3I and 32 and the entire unit I8 can be formed by inexpensive machining operations. For example the slots 33 can be cut with a grinder, a milling cutter, or a shaper.
- Small diameter holes 34 are .formed through the body of the rotor I81) and connect the bottoms 33a of diametrically opposed slots 33. These holes 34 slidably receive pins 23 mentioned hereinabove.
- a vane or blade 22 is slidablv mounted in each slot 33; As best shown in Figures 9 and 10.
- these vanes 22 are of generally rectangular configuration for sliding fit in the grooves, and have end edges terminating flush with the faces 3
- the outer end 22a of each blade has a rounded, preferable fragmental cylindrical surface so that the blade will have line contact only with the liner and will have the major porton of its end face spaced from the liner even when in line contact therewith.
- One side face of the blade has grooves 22b connecting the rounded outer end face 22a with the flat inner end face 220. These grooves 22b serve to vent the blind bottoms of the slots 33 with the pumping chamber of the pump as will more fully hereinafter be described.
- the pins 23 in the holes 34 thrust against the inner faces 220 of the blades.
- the seal assembly I9 shown in Figure 3 includes a metal cup member 35 seated in the bore I4 of the casing II and having a flange bottomed on the shoulder I5.
- a sealing washer 36 composed of felt, rubber, or the like fits in the cup 35 against the flange thereof and receives therein the reduced diameter portion of a sealing ring 31 which slides in the cup 35 and receives the shaft Ilia freely therethrough.
- This seal ring 31 has a raised end face 31a urged by the resilient washer 36 against the face of a coacting seal ring 38 which is pressed on the shaft I8a.
- seal assembly I9 seals a chamber 33 in the bore I4.
- the front end bearing block 20 is seated in the bore I2 against the shoulder I3 and rotatably supports the shaft I8a.
- This block 20 has a cylindrical bore 20a therethrough providingradial bearing for the shaft I8a and a fiat end face 20b providing a thrust bearing for the front side face 3
- a slot 40 shown in Figures 3, 5, 6 and i1, is provided in the peripheral portion of the block 23 and extends circumferentially of the block as best illustrated in Figures 5 and 6.
- a bore 4I extends radially inward of the peripheral portion of the block 20 through the slot 40 to a shoulder 42.
- a passageway 43 connects the bore M with the sealed chamber 39.
- a ball 44 is bottomed by a spring 45 on the shoulder 42 to close the passagewa 43.
- the spring 45 is bottomed on the wall of the bore I2 of the casing and coacts with the ball 44 to provide a check valve preventing flow from the slot 40 to the chamber 39 but permitting flow from the chamber 39 to the slot 40 whenever the pressure differential between the chamber 39 and slot 40 is sufllciently great to overcome the load of the spring.
- the slot 40 is adapted to'communicate with either the recess Ba or the recess 90 depending upon the position of the bearing block 20.
- This bearing block 20 has a pair of holes 46 drilled therethrough-for receiving the locking pin 25. Since the slot 40 should communicate with the intake port to drain the seal chamber 39, the bearing block 20 is positioned either as-shown in Figure 5 or in Figure 6, depending upon the direction in which the pump is to be rotated. If the pumpis rotated in a direction so that the port 8 becomes the inlet port, the slot 40 will register with the recess 8a as shown in Figure 5. If, on the other hand, the port 9 isthe inlet port, because of opsure side of the pump.
- has a cylindrical outer periphery for snugly fitting the bore l2, and an inner periphery defining a pump bore.
- is bottomed against the face 2% of the bearing block 20.
- the other face of the liner receives the bearing block 24 thereagainst.
- the liner has a single hole 41 for receiving the pin 25 therethrough.
- the bearing block 24 like the block 20, snugly fits in the bore l2 and-has a bore 24'; therethrough affording a radial bearing for the shaft portion I80 together with an end face 24?; affording a thrust bearing for the rotor face 32.
- a single hole.48 is drilled through theblock 24 to register with the hole 4"! for receiving the locking pin 25. As shown in Figure 3, this locking pin 25 extends into a well 49 communicating with the shoulder l3 of the casing.
- the spring 26 acts on the bearing block 24 and is centered around a collar portion of this block.
- the spring is bottomed on the end cover 21 which snugly fits in the'bore 12 of the casing and has a sealing gasket or ring 50 therearound .for sealing engagement with the bearing block 24.
- the retainer ring 28 is seated in the groove I1 and can be sprung out of the groove to permit access to the interior of the housing. The pin seated so that the bearing block 23 can be shifted in accordance with the desired direction of rotation of the rotor.
- has passageways 5
- the rotor 18b is eccentrically disposed in the bore of the liner as shown.
- the height or length of two blades 22 plus the length of one pin 23 plus the desired clearance is equal to the bore diameter of the liner.
- the pins 23 hold the blades 22 against the liner to produce the operating effect of through-rotor blades or vanes without the attendant disadvantages of such through blades or vanes.
- the grooves 22b on the side face of the blade 22 can either be on the leading or trailing side of the blades.
- the leading side of the blade and the closed end of the rotor slot 33 is thereby vented to the pres-
- the grooves 22b are on ing the blade against the liner is assisted by pump pressure equivalent to the force exerted by the pump pressure on the full inner edge 220 of the blade minus the pump pressure exerted on one-half of the outer face 22a of the blade.
- the invention provides an inexpensive vane-type pump adapted for clockwise or counterclockwise rotation and having a shiftable bearing block for selectively venting a sealing chamber to the intake port of the pump together with a peripherally slotted rotor carrying blade-actuating pins and equipped with grooved blades to vent the blind ends of the slots.
- a rotary vane pump comprising a casing having a stepped bore therethrough with longitudinally spaced first and second shoulders pulsation, and is highly between the bores, a seal assembly in one fbore.
- a rotor unit having a rotor block in another bore and a first shaft portion extending therefrom through the seal assembly together with a second shaft por tatably supporting said second shaft portion, a
- a rotary vane type pump comprising a casing having a first chamber extending inwardly from one face thereof and terminating in a shoulder together with a second chamber beyond said shoulder, a vane rotor in said first chamber having one shaft portion extending through said second chamber andanother shaft portion extending in the oposite direction in said first chamber, a seal assembly in said second chamber surrounding said one shaft portion therein and coacting therewith for sealing the second chamber, opposed bearing blocks in said first chamber receiving said shaft portions and forming thrust faces for the sides of the rotor, one of said bearing blocks being bottomed on said shoulder, a liner between said bearing blocks, a cover for the open end of the first chamber, a spring interposed between the cover and the other of said bearing blocks and urging both said blocks and the interposed liner toward said shoulder, said casing having interchangeable inlet and outlet ports, said bearing block bottomed n the shoulder having a passageway connecting the sealed second chamber with a port, a spring-pressed check valve in said passageway for sealing the passage
- a pump construction comprising a casing having an open end face, pump parts in said casing removable through said open end face, said parts including opposed bearing blocks and a rotor and shaft assembly rotatably mounted in said blocks with the rotor thereof between the blocks, said casing having a seal assembly therein coacting with the shaft to form a sealed chamber receiving the shaft therethrough, one of said bearing blocks having a passageway communicating with said chamber, inlet and outlet ports for said casing, said onebearing block being angularly positionable in the casing to. selectively move the passageway thereof into registration with either one of said ports, and a removable pin lockingboth of said bearing blocks in the casing in either angular position of said one bearing block.
- a rotary vane pump comprising an assembly composed of a rotor and shaft unit having a vaned circular block portion with shafts extending from opposite faces thereof, a liner surrounding the vaned portion of said unit, bearing blocks abutting the ends of the liner and forming radial bearings for the shafts together with thrust bearings for the rotor, and a locking pin extending through the bearing blocks and the liner, one of said bearing blocks having a pair of apertures for the locking pin to permit selective rotary displacement of said one bearing block relative to the liner and other bearing block, a casing receiving the assembly and having opposed ports, and a passageway through said one bearing block joining a chamber of the casing with one port of the casing whereby the shifting of said one heating block as permitted by selective insertion of said locking pin into said pair of apertures will selectively connect said chamber with one or the other ports of the casing.
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Description
Oct. 10, 1950 J. M. ROTH EI'AL PUMP Filed Feb. 13, 1947 2 Sheets -Sheet 1 5 Mall 22 15 4* JAY M. ROTH. LESLIE L. ASPELIN.
Oct. 10, 1950 J. M. ROTH ET'AIL. 2,525,619
PUMP
Filed. Feb. 13, 194'? 2 Sheets-Sheet z 4&7
Patented a. 10, 1950 Jay M. Roth,
mastitis Leslie L'. Aspelin,
Cleveland Heights, Qhio, assignors to Thompson Products, tion of Ohio Inc, Cleveland, Ohio, at corpora- Application February 13, 1947, Serial No. 728,258
4 Claims. (Cl. 103-137) This invention relates to pumps and particularly to rotary vane type pumps.
According -to this invention an eiilcient, inexpensive rotary vane type pump is so constructed and arranged that it can operate in a clockwise direction or in a counter-clockwise direction, can be inexpensively formed without heretoforenecessary machining operations, has a suction drained seal chamber, is non-pulsating. and is relatively free from liner wear. The rotor for the pump has integral shaft portions projecting from opposite side faces thereof and has vanereceiving slots at spaced intervals around the periphery thereof and extending through the side faces thereof so that they are cheaply formed by a shaper, a grinder, or a milling cutter. These vane slots have solid bottoms and the bottoms of diametrically opposed slots are connected through drilled holes. Pins slidably ride in these holes and act on the inner ends of the vanes to maintain the vanes in contact with the pump liner.
The vanes preferably have rounded outer ends for riding on the pump liner and grooves on one side face thereof to vent the inner ends of the rotor slots to the pumping chamber between the rotor and liner. The vanes are reversible to have their grooved faces on either side. If the grooves are on the trailing sides of the vanes,
the inner ends of the vanes are only subject to negative inlet pressures and the thrust on the vanes due to discharge pressure acting on their rounded outer ends is inward to subtract from the centrifugal force tending to hold the vanes tightly against the liner. If the grooves are on the leading sides of the vanes, the inner ends of the vanes are exposed to discharge pressure and the outer ends of the vanes will be forced against the pump liner to add to the centrifugal force. 'Pulsations due to vane retractions are eliminated because fluid trapped behind the vanes is released to occupy the space in the pumping chamber which was previously occupied by the extended ends of the vanes.
A feature of the invention resides in the provision of bearing blocks which rotatably mount the rotor shaft portions and also provide thrust bearings for the opposite side faces of the rotor to close the open ends of the rotor slots.
A further feature resides in the provision of a sealed chamber through which the pump rotor shaft projects and which is selectively drained into the port functioning as the inlet port of the pump as determined by the direction of operation of operation of the pump.
Another feature resides in the provision of a locking pin arrangement for the pump bearing blocks which permits shifting of one of the blocks to'connect the sealed chamber selectively with ports on opposite sides of the pump.
It is, then, an object of this invention to provide a vane type pump with a peripherally slotted rotor wherein the slots have closed bottoms and open ends and wherein the closed bottoms of opposed slots are connected by holes for receivmg pms.
A further object of the invention is to provide an inexpensive rotary vane pump with a rotor having integral shafts projecting from opposite faces thereof and equipped with peripheral slots extending through said faces whereby bearing blocks on the shaft portions afford thrust bearings for the opposite faces of the rotor as well as radial bearings for the shaft portions.
A further object of the invention is to provide a closed bottomed slotted rotor for pumps with pins connecting opposed rotor slots for acting on the inner ends of vanes therein.
A still further object of the invention is to provide a pump with a shiftable ported bearing block adapted to selectively connect a seal chamber of the pump with a port of the pump.
A still further object of the invention is to provide a rotory vane pump having closed bottom vane slots in the rotor thereof slidably receiving vanes with rounded outer ends riding on the bore of the pump liner wherein one side face of the vanes is grooved to vent' the inner ends of the closed bottom slots with the pumping chamber on either the inlet or discharge side of the chamber to control the force pump liner.
Another object of the invention is to'block off opposed rotor slots in a rotary vane pump and balance the pressure on the blades of the pump by means of relief grooves for eliminating severe liner wear heretofore encountered on the inlet side of a pump by discharge pressure action on through-rotor vanes.
Other and further objects of the invention will be apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which, by way of a preferred example only, illustrate one embodiment of the invention.
0n th drawings:
Figure 1 is a front end elevational view pump of this invention.
Figure 2 is a side elevational view of the pump.-
Figures is a longitudinal vertical cross-secof the of seating the vanes on the tional view taken along the line III-411 of Figure 1.
Figure 4 is a transverse vertical cross-sectional view with parts in end elevation taken along the line IV-IV of Figure 2.
Figure 5 is a fragmentary transverse cross-sec- -tional view taken along the line V--V of Figure 3 and illustrating the position of the bearing block for connecting the sealing chamber of the pump with an inlet port on one side of the pump.
Figure 6 is a view similar to Figure 5 but illustrating the position of the bearing block for connecting the sealing chamber with an inlet port on the other side of the pump.
Figure 7 is an enlarged side elevational view, with parts in vertical cross section, of the rotor and shaft unit for the pump of the invention.
Figure 8 is an end elevational view of the shaft and rotor unit'bf Figure 7.
Figure 9 is an outer end elevational view of a vane for the pump.
Figure 10 is a side elevational view of the grooved side of the vane.
Figure. 11 is an enlarged vertical cross-sectional view of the shiftable bearing block for the pump. t
Figure 12 is a diagrammatic fragmentary view illustrating forces on the vane when the grooved face thereof'is on the leading side of the vane.
Figure 13 is a view similar to Figure 12 but illustrating the forces on the vane when the grooved face of the vane is on the trailing side.
As shown on the drawings:
The ump I shown in Figures 1 to 4 has a casing I I with a generally cylindrical portion I la extendin to a radial flange IIb and a rounded cylindrical nose IIc projecting from the central portion of the opposite face of the flange. The casing II has a cylindrical bore I2 extending inwardly from the rear face thereof through the portion Ila to a shoulder I3. A smaller diameter bore I4 extends from the inner end of the shoulder I3 through the portion I I0 of the housing to a shoulder I5. A still smaller diameter bore I6 extends from the shoulder I through the front end face of the housing portion Ilc. A groove I1 is formed in the bore I2 adjacent the rear end face of the portion Ila of the casing.
The casing, as best shown in Figures 2 and 4, has bosses I Id and He extending radially outward from the casing portion Ila and terminating flush with the outer face of the flange IIb. These bosses I Id and I Ie provide ports 8 and 9 which extend radially through the bosses and communicate at their inner ends with recesses 8a and 9a respectively formed in the bore I2 and having the configuration shown in Figure 2. As
, will be hereinafter more fully described, these recesses 8a and 9a communicate with the pumping chamber of the pump.
As best shown in Figure 3, the pump includes a unitary shaft and rotor I8, a seal assembly I9, a front end bearing block 20, a liner 2|, vanes 22 in the rotor, pins 23 acting on the inner ends of the vanes, a rear end bearing block 24, a locking pin 25, a spring 26 acting on the bearing block 24, a cover 2I,'and a retainer 28.
As best shown inFigure '7, the shaft and rotor unit I8'includes an elongated shaft portion IBa, a larger diameter circular block portion I81), and a shorter shaft portion I80. The shaft portions I8a and I80 are in axial alignment. The outer end of the shaft portion I8a has a key slot 29 therein for coupling with a driver (not shown).
The block portion I8b constitutes a rotor for the pump and has a circular outer periphery 30 of materially larger diameter than the shafts I8a. and I8c together with flat side faces including a front side face 3| and a rear side face 32. Radial slots 33 extend inwardly from the periphery 30 and are cut through the side faces 3| and 32. As best shown in Figure 8, four slots 33 are provided and each of these slots terminates at a flat bottom 33a spaced radially outward from the shaft I Be. The slots 33 are easily out since they extend through the faces 3I and 32 and the entire unit I8 can be formed by inexpensive machining operations. For example the slots 33 can be cut with a grinder, a milling cutter, or a shaper.
Small diameter holes 34 are .formed through the body of the rotor I81) and connect the bottoms 33a of diametrically opposed slots 33. These holes 34 slidably receive pins 23 mentioned hereinabove.
A vane or blade 22 is slidablv mounted in each slot 33; As best shown in Figures 9 and 10.
. these vanes 22 are of generally rectangular configuration for sliding fit in the grooves, and have end edges terminating flush with the faces 3| and 32 of the rotor IBb. The outer end 22a of each blade has a rounded, preferable fragmental cylindrical surface so that the blade will have line contact only with the liner and will have the major porton of its end face spaced from the liner even when in line contact therewith. One side face of the blade has grooves 22b connecting the rounded outer end face 22a with the flat inner end face 220. These grooves 22b serve to vent the blind bottoms of the slots 33 with the pumping chamber of the pump as will more fully hereinafter be described. The pins 23 in the holes 34 thrust against the inner faces 220 of the blades.
The seal assembly I9 shown in Figure 3 includes a metal cup member 35 seated in the bore I4 of the casing II and having a flange bottomed on the shoulder I5. A sealing washer 36 composed of felt, rubber, or the like fits in the cup 35 against the flange thereof and receives therein the reduced diameter portion of a sealing ring 31 which slides in the cup 35 and receives the shaft Ilia freely therethrough. This seal ring 31 has a raised end face 31a urged by the resilient washer 36 against the face of a coacting seal ring 38 which is pressed on the shaft I8a. seal assembly I9 seals a chamber 33 in the bore I4.
The front end bearing block 20 is seated in the bore I2 against the shoulder I3 and rotatably supports the shaft I8a. This block 20 has a cylindrical bore 20a therethrough providingradial bearing for the shaft I8a and a fiat end face 20b providing a thrust bearing for the front side face 3| of the rotor IBb, as best shown in Figure 11. I
A slot 40, shown in Figures 3, 5, 6 and i1, is provided in the peripheral portion of the block 23 and extends circumferentially of the block as best illustrated in Figures 5 and 6. A bore 4I extends radially inward of the peripheral portion of the block 20 through the slot 40 to a shoulder 42. A passageway 43 connects the bore M with the sealed chamber 39. A ball 44 is bottomed by a spring 45 on the shoulder 42 to close the passagewa 43. The spring 45 is bottomed on the wall of the bore I2 of the casing and coacts with the ball 44 to provide a check valve preventing flow from the slot 40 to the chamber 39 but permitting flow from the chamber 39 to the slot 40 whenever the pressure differential between the chamber 39 and slot 40 is sufllciently great to overcome the load of the spring.
.As illustrated in Figures and 6, the slot 40 is adapted to'communicate with either the recess Ba or the recess 90 depending upon the position of the bearing block 20. This bearing block 20 has a pair of holes 46 drilled therethrough-for receiving the locking pin 25. Since the slot 40 should communicate with the intake port to drain the seal chamber 39, the bearing block 20 is positioned either as-shown in Figure 5 or in Figure 6, depending upon the direction in which the pump is to be rotated. If the pumpis rotated in a direction so that the port 8 becomes the inlet port, the slot 40 will register with the recess 8a as shown in Figure 5. If, on the other hand, the port 9 isthe inlet port, because of opsure side of the pump. Therefore pump pressure acts on the innerfac 22c of the blade forcing the blade outwardly against the liner 2|. This outward force is resisted by the component of inward force created by pump pressure acting -on the rounded face 22a of the blade. One- I in Figure 12, the centrifugal force effect of holdposite rotation of the pump, the bearing block I will be shifted to receive the pin in the other hole 46 thereof so that the slot 42 will communicate with the recess 9a. In thismanner the sealed chamber 39 is always vented to the inlet port and fluid leaking into the chamber is fed back into the pump. a I
The pump liner 2| has a cylindrical outer periphery for snugly fitting the bore l2, and an inner periphery defining a pump bore. One face of the liner 2| is bottomed against the face 2% of the bearing block 20. The other face of the liner receives the bearing block 24 thereagainst. The liner has a single hole 41 for receiving the pin 25 therethrough.
The bearing block 24, like the block 20, snugly fits in the bore l2 and-has a bore 24'; therethrough affording a radial bearing for the shaft portion I80 together with an end face 24?; affording a thrust bearing for the rotor face 32. A single hole.48 is drilled through theblock 24 to register with the hole 4"! for receiving the locking pin 25. As shown in Figure 3, this locking pin 25 extends into a well 49 communicating with the shoulder l3 of the casing.
The spring 26 acts on the bearing block 24 and is centered around a collar portion of this block. The spring is bottomed on the end cover 21 which snugly fits in the'bore 12 of the casing and has a sealing gasket or ring 50 therearound .for sealing engagement with the bearing block 24. The retainer ring 28 is seated in the groove I1 and can be sprung out of the groove to permit access to the interior of the housing. The pin seated so that the bearing block 23 can be shifted in accordance with the desired direction of rotation of the rotor.
The liner 2|, best shown in Figure 4, has passageways 5| and 52 therethrough aligned with the recesses 8a and So for joining the ports 8 and 9 with the pumping chamber 0. The rotor 18b is eccentrically disposed in the bore of the liner as shown. The height or length of two blades 22 plus the length of one pin 23 plus the desired clearance is equal to the bore diameter of the liner. The pins 23 hold the blades 22 against the liner to produce the operating effect of through-rotor blades or vanes without the attendant disadvantages of such through blades or vanes.
As best illustrated in Figures 12 and 13 the grooves 22b on the side face of the blade 22 can either be on the leading or trailing side of the blades. the leading side of the blade and the closed end of the rotor slot 33 is thereby vented to the pres- In Figure 12, the grooves 22b are on ing the blade against the liner is assisted by pump pressure equivalent to the force exerted by the pump pressure on the full inner edge 220 of the blade minus the pump pressure exerted on one-half of the outer face 22a of the blade.
As illustrated in Figure 13, when the grooves 22b are on the trailing side of the blade, the blind end of the slot 33 is vented to inlet pressure, and, since this inlet pressure is usually a negative pressure, or suction, there is a tendency for the blade to be drawn into the blind end of the slot. This tendency, of course, is resisted by centrifugal force and also by the pin.
23 whenever the blade engages the pin.. The arrangement of Figure 13 reduces blade liner contact pressure, while the arrangement of"Fig-' ure 12 increases this pressure. Since the rotor slots 33 have blind bottoms 33a, discharge pressure on the outer ends 22a of the blades is not transmitted to the inner ends of the opposite blades on the intake side of the pump. This eliminates heretofore-encountered severe liner wear around the intake side of the liner.
Since the blind inner ends of the slots 33 are vented through the grooves 22b with the pumping chamber, fluid trapped in the slots is fed to and from the pumping chamber 0 in accordance with the shifting movements of the blades to occupy the volume occupied in the pumping chamber by the extended ends of the blades.
This feature eliminates desirable.
From the above descriptions it should be understood that the invention provides an inexpensive vane-type pump adapted for clockwise or counterclockwise rotation and having a shiftable bearing block for selectively venting a sealing chamber to the intake port of the pump together with a peripherally slotted rotor carrying blade-actuating pins and equipped with grooved blades to vent the blind ends of the slots.
It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope oi: the appended claims.
We claim as our invention:
1. A rotary vane pump comprising a casing having a stepped bore therethrough with longitudinally spaced first and second shoulders pulsation, and is highly between the bores, a seal assembly in one fbore.
bottomed on the first shoulder, a rotor unit having a rotor block in another bore and a first shaft portion extending therefrom through the seal assembly together with a second shaft por tatably supporting said second shaft portion, a
liner between said bearing blocks surrounding said rotor block and coacting therewith to define a pumping chamber, a removable end cap closing said another bore, a spring compressed between said end cap and said second bearing block urging the bearing block against the liner, said rotor having a plurality of open-sided vane slots having the open sides closed by the bearing blocks, vanes slidable in said slots, said casing having interchangeable inlet and outlet ports, means providing a passageway through the first bearing block communicating at one end with the sealed chamber, and means for locking the first bearing block in selected positions in said casing to join the other end of said passageway only with the port selected for the inlet port.
2. A rotary vane type pump comprising a casing having a first chamber extending inwardly from one face thereof and terminating in a shoulder together with a second chamber beyond said shoulder, a vane rotor in said first chamber having one shaft portion extending through said second chamber andanother shaft portion extending in the oposite direction in said first chamber, a seal assembly in said second chamber surrounding said one shaft portion therein and coacting therewith for sealing the second chamber, opposed bearing blocks in said first chamber receiving said shaft portions and forming thrust faces for the sides of the rotor, one of said bearing blocks being bottomed on said shoulder, a liner between said bearing blocks, a cover for the open end of the first chamber, a spring interposed between the cover and the other of said bearing blocks and urging both said blocks and the interposed liner toward said shoulder, said casing having interchangeable inlet and outlet ports, said bearing block bottomed n the shoulder having a passageway connecting the sealed second chamber with a port, a spring-pressed check valve in said passageway for sealing the passageway whenever inlet port pressure is greater than the pressure in the sealed second chamber, and means for selectively angularly positioning said passaged bearing block relative to said casing to move said passageway into registration with whichever port is selected for the inlet port whereby said pump can be driven in either direction and still have the sealed chamber thereof drained into the inlet port.
3. A pump construction comprising a casing having an open end face, pump parts in said casing removable through said open end face, said parts including opposed bearing blocks and a rotor and shaft assembly rotatably mounted in said blocks with the rotor thereof between the blocks, said casing having a seal assembly therein coacting with the shaft to form a sealed chamber receiving the shaft therethrough, one of said bearing blocks having a passageway communicating with said chamber, inlet and outlet ports for said casing, said onebearing block being angularly positionable in the casing to. selectively move the passageway thereof into registration with either one of said ports, and a removable pin lockingboth of said bearing blocks in the casing in either angular position of said one bearing block.
4. A rotary vane pump comprising an assembly composed of a rotor and shaft unit having a vaned circular block portion with shafts extending from opposite faces thereof, a liner surrounding the vaned portion of said unit, bearing blocks abutting the ends of the liner and forming radial bearings for the shafts together with thrust bearings for the rotor, and a locking pin extending through the bearing blocks and the liner, one of said bearing blocks having a pair of apertures for the locking pin to permit selective rotary displacement of said one bearing block relative to the liner and other bearing block, a casing receiving the assembly and having opposed ports, and a passageway through said one bearing block joining a chamber of the casing with one port of the casing whereby the shifting of said one heating block as permitted by selective insertion of said locking pin into said pair of apertures will selectively connect said chamber with one or the other ports of the casing.
JAY M. ROTH. LESLIE L. ASPELIN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,002,023 Beach et a1 Aug. 29, 1911 1,245,691 Deyser Nov. 6, 1917 1,730,145 Hildreth Oct.'1, 1929 1,816,508 Wilsey July 28, 1931 1,898,914 Vickers Feb. 21, 1933 2,037,894 Grisell 1 Apr. 21, 1936 2,210,152 Sacha Aug. 6, 1940 2,260,809 Johnson Oct. 28, 1941 2,312,891 Ferris Mar. 2, 1943 2,335,284 Kendrick Nov. 30, 1943 FOREIGN PATENTS Number Country Date 215,659 Great Britain May 15, 1924 417,348 Great Britain Oct. 3, 1934 433,488 Great Britain Aug. 15, 1935 543,037 France May 26, 1922
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US728258A US2525619A (en) | 1947-02-13 | 1947-02-13 | Pump |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US728258A US2525619A (en) | 1947-02-13 | 1947-02-13 | Pump |
Publications (1)
Publication Number | Publication Date |
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US2525619A true US2525619A (en) | 1950-10-10 |
Family
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US728258A Expired - Lifetime US2525619A (en) | 1947-02-13 | 1947-02-13 | Pump |
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Cited By (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2623471A (en) * | 1951-03-12 | 1952-12-30 | Hartmann Mfg Company | Vane type pump or motor |
US2653550A (en) * | 1950-10-07 | 1953-09-29 | Vickers Inc | Power transmission |
US2671409A (en) * | 1950-08-01 | 1954-03-09 | Tokheim Corp | Direct-drive gasoline dispensing pump |
US2694580A (en) * | 1951-02-27 | 1954-11-16 | Head Ski Co Inc | Composite wood and metal ski having plastic running surface |
US2694982A (en) * | 1951-09-13 | 1954-11-23 | Oliver Iron And Steel Corp | Hydraulic machine |
US2764941A (en) * | 1953-08-21 | 1956-10-02 | Racine Hydraulics And Machiner | Multiple pump |
US2765750A (en) * | 1954-03-09 | 1956-10-09 | Hartmann Mfg Company | Fluid pump or motor |
US2844945A (en) * | 1951-09-19 | 1958-07-29 | Muffly Glenn | Reversible refrigerating systems |
US2845873A (en) * | 1954-09-08 | 1958-08-05 | Clark Equipment Co | Rotating fluid pump |
US2853023A (en) * | 1955-08-12 | 1958-09-23 | American Brake Shoe Co | Fluid energy translating apparatuses |
US2856860A (en) * | 1955-08-03 | 1958-10-21 | Mechanisms Company | Fluid pressure transducer with end clearance control |
US2924181A (en) * | 1957-05-13 | 1960-02-09 | Laval Steam Turbine Co | Screw pumps or motors |
US2925786A (en) * | 1956-11-23 | 1960-02-23 | Procon Pump & Engineering Co | Pump |
US2950046A (en) * | 1956-01-28 | 1960-08-23 | Heraeus Gmbh W C | High vacuum pump |
US2957620A (en) * | 1957-08-19 | 1960-10-25 | Automatic Power Inc | Compressor head assembly |
US2974605A (en) * | 1959-02-12 | 1961-03-14 | Borg Warner | Pressure loaded hydraulic apparatus |
US2980029A (en) * | 1956-10-05 | 1961-04-18 | Curtiss Wright Corp | Rotary vane type pump |
US3008419A (en) * | 1958-11-13 | 1961-11-14 | Constantinos H Vlachos | Combined motor and pump |
US3009420A (en) * | 1961-11-21 | Slipper pump | ||
US3119345A (en) * | 1962-05-24 | 1964-01-28 | Hypro Engineering Inc | End ported roller pump |
US3130673A (en) * | 1961-08-01 | 1964-04-28 | Arthur K Finstad | Rotary vane pump with replaceable head unit |
US3216364A (en) * | 1963-01-30 | 1965-11-09 | Raymond G Nicolas | Spherical cavity pump |
DE1226419B (en) * | 1960-10-06 | 1966-10-06 | Teves Kg Alfred | Rotary lobe pump |
US3303783A (en) * | 1964-07-01 | 1967-02-14 | Tuthill Pump Co | Fluid pump apparatus |
US3307480A (en) * | 1964-09-01 | 1967-03-07 | Carrier Corp | Automatically reversible gear pump |
US5167497A (en) * | 1990-07-12 | 1992-12-01 | Mouvex | Vane control unit for vane pump |
US20050214153A1 (en) * | 2004-03-25 | 2005-09-29 | Tuthill Corporation | Rotary vane pump |
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GB215659A (en) * | 1923-10-10 | 1924-05-15 | App Bauanstalt Axmann And Comp | Improvements in rotary piston engines |
US1730145A (en) * | 1926-04-16 | 1929-10-01 | Lamson Co | Refrigerating apparatus |
US1816508A (en) * | 1927-07-09 | 1931-07-28 | James B Tuthill | Rotary pump |
US1898914A (en) * | 1929-02-25 | 1933-02-21 | Harry F Vickers | Vane pump or motor |
GB417348A (en) * | 1933-07-05 | 1934-10-03 | Nichols Compressors Ltd | Improvements in rotary type exhausters, compressors, superchargers and the like |
GB433488A (en) * | 1934-04-26 | 1935-08-15 | Frederick Llewellyn Smith | Improvements in rotary pumps, engines, compressors or exhausters |
US2037894A (en) * | 1933-07-17 | 1936-04-21 | Grisell Lowell Hobart | Fuel pump |
US2210152A (en) * | 1939-05-22 | 1940-08-06 | Nellie M Gottschalt | Gear pump |
US2260809A (en) * | 1938-03-18 | 1941-10-28 | Pump Engineering Service Corp | Seal for rotary pumps |
US2312891A (en) * | 1939-05-19 | 1943-03-02 | Oilgear Co | Hydrodynamic machine |
US2335284A (en) * | 1939-12-06 | 1943-11-30 | Manly Corp | Rotary fluid pressure device |
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US1002023A (en) * | 1909-06-03 | 1911-08-29 | Arthur T Beach | Rotary pump. |
US1245691A (en) * | 1917-03-06 | 1917-11-06 | William L Deysher | Rotary pump. |
FR543037A (en) * | 1921-11-04 | 1922-08-25 | Rotary pump | |
GB215659A (en) * | 1923-10-10 | 1924-05-15 | App Bauanstalt Axmann And Comp | Improvements in rotary piston engines |
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US1898914A (en) * | 1929-02-25 | 1933-02-21 | Harry F Vickers | Vane pump or motor |
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US2037894A (en) * | 1933-07-17 | 1936-04-21 | Grisell Lowell Hobart | Fuel pump |
GB433488A (en) * | 1934-04-26 | 1935-08-15 | Frederick Llewellyn Smith | Improvements in rotary pumps, engines, compressors or exhausters |
US2260809A (en) * | 1938-03-18 | 1941-10-28 | Pump Engineering Service Corp | Seal for rotary pumps |
US2312891A (en) * | 1939-05-19 | 1943-03-02 | Oilgear Co | Hydrodynamic machine |
US2210152A (en) * | 1939-05-22 | 1940-08-06 | Nellie M Gottschalt | Gear pump |
US2335284A (en) * | 1939-12-06 | 1943-11-30 | Manly Corp | Rotary fluid pressure device |
Cited By (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3009420A (en) * | 1961-11-21 | Slipper pump | ||
US2671409A (en) * | 1950-08-01 | 1954-03-09 | Tokheim Corp | Direct-drive gasoline dispensing pump |
US2653550A (en) * | 1950-10-07 | 1953-09-29 | Vickers Inc | Power transmission |
US2694580A (en) * | 1951-02-27 | 1954-11-16 | Head Ski Co Inc | Composite wood and metal ski having plastic running surface |
US2623471A (en) * | 1951-03-12 | 1952-12-30 | Hartmann Mfg Company | Vane type pump or motor |
US2694982A (en) * | 1951-09-13 | 1954-11-23 | Oliver Iron And Steel Corp | Hydraulic machine |
US2844945A (en) * | 1951-09-19 | 1958-07-29 | Muffly Glenn | Reversible refrigerating systems |
US2764941A (en) * | 1953-08-21 | 1956-10-02 | Racine Hydraulics And Machiner | Multiple pump |
US2765750A (en) * | 1954-03-09 | 1956-10-09 | Hartmann Mfg Company | Fluid pump or motor |
US2845873A (en) * | 1954-09-08 | 1958-08-05 | Clark Equipment Co | Rotating fluid pump |
US2856860A (en) * | 1955-08-03 | 1958-10-21 | Mechanisms Company | Fluid pressure transducer with end clearance control |
US2853023A (en) * | 1955-08-12 | 1958-09-23 | American Brake Shoe Co | Fluid energy translating apparatuses |
US2950046A (en) * | 1956-01-28 | 1960-08-23 | Heraeus Gmbh W C | High vacuum pump |
US2980029A (en) * | 1956-10-05 | 1961-04-18 | Curtiss Wright Corp | Rotary vane type pump |
US2925786A (en) * | 1956-11-23 | 1960-02-23 | Procon Pump & Engineering Co | Pump |
US2924181A (en) * | 1957-05-13 | 1960-02-09 | Laval Steam Turbine Co | Screw pumps or motors |
US2957620A (en) * | 1957-08-19 | 1960-10-25 | Automatic Power Inc | Compressor head assembly |
US3008419A (en) * | 1958-11-13 | 1961-11-14 | Constantinos H Vlachos | Combined motor and pump |
US2974605A (en) * | 1959-02-12 | 1961-03-14 | Borg Warner | Pressure loaded hydraulic apparatus |
DE1226419B (en) * | 1960-10-06 | 1966-10-06 | Teves Kg Alfred | Rotary lobe pump |
US3130673A (en) * | 1961-08-01 | 1964-04-28 | Arthur K Finstad | Rotary vane pump with replaceable head unit |
US3119345A (en) * | 1962-05-24 | 1964-01-28 | Hypro Engineering Inc | End ported roller pump |
US3216364A (en) * | 1963-01-30 | 1965-11-09 | Raymond G Nicolas | Spherical cavity pump |
US3303783A (en) * | 1964-07-01 | 1967-02-14 | Tuthill Pump Co | Fluid pump apparatus |
US3307480A (en) * | 1964-09-01 | 1967-03-07 | Carrier Corp | Automatically reversible gear pump |
US5167497A (en) * | 1990-07-12 | 1992-12-01 | Mouvex | Vane control unit for vane pump |
US20050214153A1 (en) * | 2004-03-25 | 2005-09-29 | Tuthill Corporation | Rotary vane pump |
US7393192B2 (en) * | 2004-03-25 | 2008-07-01 | Gregory P Wood | Rotary vane pump |
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