JP2009138672A - Vane pump - Google Patents

Abstract

A vane pump that prevents a reduction in suction efficiency into a pump chamber at the time of high pump rotation or the like is provided.
A pump body 2 having a concave portion 2a, a cover member 3 for closing the concave portion 2a, a cam ring 5 disposed on an inner peripheral side of the concave portion 2a, and the cam ring 5 together with the cover member 3 are sandwiched. Plate member 8, a seal plate 9 and a seal member 10 interposed between the pump body 2 and the cover member 3, and a suction passage 17 formed from the pump body 2 to the cover member 3. is doing. A space portion S communicating with the suction passage 17 is formed on the inner peripheral side of the seal member 10, an axial groove 23 is formed on the outer periphery of the cam ring 5, and the inner periphery of the axial groove 23 and the recess 2 a is formed. A communication passage was formed between the surface portion and the space S and the plate member side suction port 15 of the plate member 8 was communicated.
[Selection] Figure 1

Description

  The present invention relates to a vane pump used for, for example, a drive source of a power steering of a vehicle.

  As this type of conventional vane pump, for example, the one described in Patent Document 1 below is known.

  Briefly, a pump body having a recess opening on one side, a cover member arranged on one side of the pump body to close the recess, and rotatably supported by the pump body and the cover member A drive shaft, a cam ring disposed on the inner peripheral side of the recess, a rotor disposed on the inner peripheral side of the cam ring and fixed to the drive shaft, and a plurality of slots formed in the rotor. And a plurality of vanes that define a plurality of pump chambers between the cam ring and the rotor, and a plate member that is disposed on the bottom side of the recess and holds the cam ring together with the cover member. And a seal plate interposed between the pump body and the cover member and having a seal member integrally fixed to the inner periphery thereof.

  The side of the cover member facing the one side of the pump body has a cover member side suction port that opens to a region where the volume of the plurality of pump chambers increases, and the volume of the plurality of pump chambers decreases. A cover member-side discharge port that opens in the region is formed.

  Further, a plate member side suction port and a plate member side discharge port are formed at positions corresponding to the suction port and the discharge port formed in the cover member on one side of the plate member.

  The pump body is formed with a suction port through which hydraulic oil is introduced from an external reservoir tank or the like, and a suction passage is formed from the suction port toward the cover member. The suction passage extends inside the cover member and communicates with the cover member-side suction port.

The cam ring is formed with a through hole for communicating the cover member side suction port with the plate member side suction port, and a part of the hydraulic oil flowing into the cover member side suction port is passed through the cam ring. It is made to flow into the suction port of the plate member through a hole to supplement the suction amount of the hydraulic oil into the pump chamber.
JP-A-62-271982 (FIGS. 1 and 3)

  However, in the conventional vane pump, as described above, a part of the hydraulic oil that has flowed into the cover member side suction port is guided to the plate member side suction port through the through hole of the cam ring. Although the dose is to be supplemented, this inhalation amount is insufficient.

  Therefore, in order to increase the amount of the hydraulic oil flowing into the plate member side suction port, it is conceivable to increase the diameter of the through hole. However, in this case, the rigidity of the cam ring is reduced. Therefore, there is a limit to the expansion of the hole diameter. As a result, the inflow amount of the hydraulic oil flowing into the pump chamber cannot be increased.

  Accordingly, there is a risk that the amount of the hydraulic oil flowing from the plate member side suction port into the pump chamber will be insufficient during high pump rotation.

  The present invention has been made in view of the above-described conventional technical problems, and prevents a decrease in pump efficiency at a high speed or the like by increasing the supply amount of the hydraulic oil to the plate member side suction port. The purpose is to do.

  The present invention has been devised in view of the conventional situation, and the invention according to claim 1 is a pump body having a recess opening on one side and the pump body disposed on one side of the pump body. A cover member that closes the recess; a drive shaft that is rotatably supported by the pump body and the cover member; a cam ring that is disposed on an inner peripheral side of the recess; A rotor fixed to a shaft; a plurality of vanes provided in a plurality of slots formed in the rotor; and a plurality of vanes separating a plurality of pump chambers between the cam ring and the rotor; and a bottom of the recess A plate member that is disposed on the side and holds the cam ring together with the cover member; and a cover member that is formed on the cover member and opens to a region where the volumes of the plurality of pump chambers increase. A suction port, a cover member-side discharge port that opens to a region where the volumes of the plurality of pump chambers decrease, and a plate member side that is formed in the plate member and opens to a region where the volumes of the plurality of pump chambers increase A suction port; a plate member-side discharge port that opens to a region where the volume of the plurality of pump chambers decreases; a suction passage that is formed from the pump body to the cover member and communicates with the cover member-side suction port; A seal plate interposed between the pump body and the cover member and having a seal member integrally fixed on the inner periphery thereof, and a space portion communicating with the suction passage on the inner periphery side of the seal member And a communication passage for communicating the space and the plate member side suction port is formed between the inner peripheral surface of the recess and the outer peripheral surface of the cam ring. It is characterized in that the.

  In the present invention, part of the hydraulic oil flowing from the suction passage into the cover member side suction port flows into the plate member side suction port from the space portion through the communication passage. As a result, the inflow amount of the hydraulic oil flowing into the pump chamber from the plate member side suction port increases.

  Accordingly, it is possible to secure a sufficient amount of the hydraulic oil flowing into the pump chamber when the pump is rotating at a high speed.

  Hereinafter, each embodiment of the vane pump concerning the present invention is explained in full detail based on a drawing. In each of the embodiments, the present invention is applied to a power steering device for a vehicle.

  That is, the vane pump 1 provided for the first embodiment is disposed on one side of the pump body 2 and the pump body 2 having a recess 2a opened on one side, as shown in FIGS. A cover member 3 for closing the recess 2a; a drive shaft 4 rotatably supported by the pump body 2 and the cover member 3; a cam ring 5 disposed on an inner peripheral side of the recess 2a; A rotor 6 disposed on the inner peripheral side and fixed to the drive shaft 4; a plurality of slots 6a formed radially on the outer peripheral side of the rotor 6; and vanes provided in the slots 6a so as to be able to appear and retract. 7, a plate member 8 that is disposed on the bottom side of the recess 2 a and holds the cam ring 5 together with the cover member 3, and is interposed between the pump body 2 and the cover member 3. The A genus-made sealing plate 9, and is mainly composed of the inner peripheral side is fixed a rubber seal member 10 Metropolitan of the seal plate 9.

  The pump body 2 is formed with a bearing accommodating portion 2b that accommodates a bearing 11 that supports the drive shaft 4 in the other side opposite to the concave portion 2a. A suction port 2c through which hydraulic oil is introduced from a reservoir tank (not shown) is formed at a predetermined position on the outer periphery.

  The recess 2a is formed by a substantially circular groove at a substantially central position in the radial direction of the pump body 2, and a groove 2d is formed at the bottom.

  The cover member 3 is disposed such that one end surface 3a faces the one end surface 2e of the pump body 2, and a bush housing groove 3b is formed at a substantially central position in the radial direction of the end surface 3a.

  The drive shaft 4 has one end 4 a rotatably supported inside the bush housing groove 3 b of the cover member 3 via a bush 12 and the other end 4 b is a bearing housing 2 b of the pump body 2. Is rotatably supported through the bearing 11. Further, a pulley (not shown) is coupled to the tip of the other end 4b, and is connected to the pulley via a belt or the like and driven to rotate. A spline unevenness 4c is formed on the outer periphery on the one end 4a side.

  As shown in FIGS. 1 to 3, the cam ring 5 is formed in a substantially annular shape, and is formed with a substantially elliptical cam surface 5a on the inner periphery, and at a substantially central position of the radial width. A through hole 5b is formed penetrating in the direction. A pair of the through holes 5b is formed at a position of approximately 180 ° in the circumferential direction. A knock pin groove 5d is formed at a predetermined position on the outer periphery. A pair of the knock pin grooves 5d is formed at a position of approximately 180 ° in the circumferential direction, and the knock pins 13 and 13 are respectively inserted into the respective knock pin grooves 5d and 5d and a knock pin hole (not shown) formed in the side surface 3a of the cover member 3. The cam ring 5 is positioned and arranged on the inner peripheral side of the recess 2 a of the pump body 2 by being fitted.

  The rotor 6 is formed in a substantially disk shape, and spline unevenness 6b is formed on the inner periphery, and the spline unevenness 6b is coupled to the drive shaft 4 by fitting with the spline unevenness 4c of the drive shaft 4. It has become.

  Further, a plurality of slots 6a formed radially from the inside of the rotor 6 to the outer peripheral side are formed at substantially equal intervals in the circumferential direction, and the vanes 7 can be projected and retracted in the slots 6a. Contained. A back pressure groove 6c for guiding back pressure is formed at the inner end of each slot 6a. By guiding the back pressure into each back pressure groove 6c, each vane 7 is connected to the outer periphery. It pushes out to the side.

  Therefore, when the rotor 6 is disposed on the inner peripheral side of the cam ring 5 and the drive shaft 4 is driven to rotate, the vanes 7 are pushed out to the outer peripheral side in the slots 6a, and the tip ends thereof. As a result of sliding along the cam surface 5 a of the cam ring 5, a plurality of pump chambers P whose volume increases or decreases are separated between the cam ring 5 and the rotor 6.

  In addition, a cover member-side suction port 14 is formed in the end surface 3a of the cover member 3 located on one side of each pump chamber P in an area where the volume of each pump chamber P increases. A cover member-side discharge port (not shown) is formed in an area where the volume of each pump chamber P decreases. The cover member side suction port 14 and the cover member side discharge port are formed in a pair at a position of approximately 180 ° in the circumferential direction.

  As shown in FIGS. 1 and 4 (a) and 4 (b), the plate member 8 is formed in a substantially disk shape, and on the outer periphery thereof, there are knock pin recesses 8a into which the knock pins 13 and 13 are fitted. A pair is formed at approximately 180 ° in the direction, and is positioned and fixed in the recess 2 a together with the cam ring 5 by the knock pins 13, 13. At this time, the groove 2d formed at the bottom of the recess 2a is separated as a high pressure chamber. A shaft insertion hole 8c through which the drive shaft 4 is inserted is formed in the center.

  One side surface 8b of the plate member 8 faces the other side of each pump chamber P, and each cover member side suction port 14, 14 of the cover member 3 and each cover member side discharge (not shown). A pair of plate member side suction ports 15 and 15 and a pair of plate member side discharge ports 16 and 16 are formed at positions corresponding to the ports, respectively.

  Furthermore, on the inner peripheral side of each plate member side suction port 15, 15 and each plate member side discharge port 16, 16, a part of the hydraulic oil discharged into the groove 2 d is transferred to the rotor 6. A back pressure introduction groove 8d for guiding to the back pressure groove 6c is formed in a substantially arc shape along the circumferential direction.

  Each of the plate member side suction ports 15, 15 is formed so as to cut out a part of the outer peripheral edge of the one side portion 9b from the inner peripheral side of the one side portion 9b. Further, part of the open ends of the plate member side suction ports 15 and 15 communicate with the through holes 5 b and 5 b of the cam ring 5.

  Each of the plate member-side discharge ports 16, 16 communicates with the groove 2d by a passage that is formed in the axial direction and is not shown.

  As shown in FIGS. 1, 2 and 5, the seal plate 9 is formed along the one end face 2e of the pump body 2 and has a width thickness t thicker than the conventional one. A seal member 10 is integrally provided on the inner peripheral side.

  As shown in FIG. 5, the seal member 10 is formed in a substantially annular shape by a rubber material or the like, and has an outer peripheral portion 10a formed in a width and thickness substantially the same as the seal plate 9, and a width wider than the outer peripheral portion 10a. It is comprised from the inner peripheral part 10b formed thickly.

  The seal member 10 is configured such that the outer peripheral portion 10 a is fixed to the inner peripheral surface of the seal plate 9 by vulcanization adhesion, and the seal plate 9 and the seal member 10 are connected to the pump body 2. When the inner peripheral portion 10b is crushed and deformed when disposed in a pinched state between the one end surface 2e and the one end surface 3a of the cover member 3, the one end surface 2e of the pump body 2 and the The cover member 3 is in close contact with the end surface 3a on one side to seal between the pump body 2 and the cover member 3.

  Further, since the seal plate 9 is formed to have an axial width and thickness t thicker than before, when the seal plate 9 is interposed between the pump body 2 and the cover member 3, A space S having substantially the same width as the width of the seal plate 9 is formed on the inner peripheral side.

  In the pump body 2 and the cover member 3, suction passages 17 for supplying hydraulic oil to the cover member side suction ports 14 and 14 are formed.

  The suction passage 17 is formed in the pump body side passage portion 18 formed inside the pump body 2 and the cover member 3 and is a cover that communicates with the pump body side suction port 18 via the space S. It is comprised from the member side channel | path part 19. FIG. Further, the downstream side of the cover member side passage portion 19 communicates with the cover member side suction port 14.

  As shown in FIGS. 1 and 2, the pump body side passage portion 18 is disposed between the recess 2a and the suction port 2c of the pump body 2 and is formed in the axial direction. The spool valve 21 that opens to the one end face 2e and controls the discharge pressure of the discharged hydraulic oil is provided at the upstream end 18b. The spool valve 21 communicates with the groove 2d through a passage not shown. The pump body side passage portion 18 communicates with the suction port 2c via the passage 2f.

  Further, a communication groove 22 is formed on the inner peripheral side of the opening end portion 18a of the pump body side passage portion 18 to connect the pump body side passage portion 18 and the recess 2a.

  As shown in FIGS. 1 and 2, the communication groove 22 is formed by notching the passage wall of the opening end portion 18 a of the pump body side passage portion 18 to the recess 2 a, and the pump body side passage portion 18. The inner periphery of the recess 2a is communicated.

  In addition, the communication groove 22 is formed in a substantially linear shape from both side ends of the center position of the opening end portion 18a of the pump body side passage portion 18 to the concave portion 2a, and the groove width T is the pump body side. The passage width of the passage portion 18 is substantially the same. Further, the depth H of the groove is formed slightly shorter than the axial width h of the space S.

  The cover member side passage portion 19 is formed from an opening side end portion 19a formed on one end surface 3a of the cover member 3 corresponding to the opening end portion 18a of the pump body side passage portion 18 of the cover member 3. It extends to the inside and branches to communicate with the cover member side suction ports 14, 14.

  A plurality of axial grooves 23 are formed on the outer periphery of the cam ring 5.

  As shown in FIGS. 2, 3A, and 3B, each of the axial grooves 23 extends in the axial direction on the outer peripheral surface of the cam ring 5, and is relatively shallow that is cut out in a substantially arc shape in cross section. It is formed by a groove and is formed substantially linearly across both end faces of the cam ring 5. The axial grooves 23 are formed at substantially equal intervals in the circumferential direction at a pitch slightly narrower than the groove width T of the communication groove 22. Accordingly, at least approximately two of the axial grooves 23 are provided adjacent to the communication groove 22.

  When the cam ring 5 is disposed on the inner peripheral side of the concave portion 2a, as shown in FIG. 1, the axial groove 23 causes a gap between the axial groove 23 and the inner peripheral surface of the concave portion 2a. A communication passage for guiding the hydraulic oil is formed at the bottom.

  Further, when the seal plate 9 and the seal member 10 are interposed between the pump body 2 and the cover member 3 and the cover member 3 is attached to the pump body 2 with a bolt or the like not shown, The space portion S and the communication groove 22 are integrated to communicate with the axial groove 23. The axial groove 23 communicates with the plate member side suction ports 15, 15 of the plate member 8.

  Hereinafter, the operation of this embodiment will be described. First, when the drive shaft 4 is rotationally driven by an engine (not shown), the rotor 6 rotates counterclockwise, and the volume of each pump chamber P increases or decreases. To do.

  Accordingly, the hydraulic oil is supplied from the suction port 2c of the pump body 2 to the inside of the pump body side passage portion 18 via the passage 2f.

  Next, the hydraulic oil that has flowed into the pump body side passage portion 18 flows into the cover member side suction ports 14 and 14 via the cover member side passage portion 19 of the cover member 3. Thus, the air is sucked into the pump chambers P from the cover member side suction ports 14 and 14.

  At this time, since each of the cover member side suction ports 14 and 14 is also communicated with each of the through holes 5b and 5b of the cam ring 5 as described above, it flows into each of the cover member side suction ports 14 and 14. A part of the hydraulic oil flows into the plate member side suction ports 15 and 15 through the through holes 5b and 5b.

  Further, a part of the hydraulic oil that is going to flow from the pump body side passage portion 18 to the cover member side passage portion 19 flows into the space S and the communication groove 22, and It flows into the plate member side suction ports 15 and 15 through the axial groove 23 and is sucked into the pump chambers P from the plate member side suction ports 15 and 15. That is, the hydraulic oil flows into the plate member-side suction ports 15 and 15 from the axial grooves 23 in addition to the hydraulic oil passing through the through holes 5b and 5b.

  Therefore, the inflow amount of the hydraulic oil flowing into the plate member side suction ports 15 and 15 increases and is supplied from the plate member side suction ports 15 and 15 into the pump chambers P. Since a sufficient supply amount of hydraulic oil can be secured, it is possible to prevent a decrease in pump suction efficiency at the time of high pump rotation.

  Further, since the axial thickness of the seal plate 9 is formed thicker than that of the conventional seal plate, and the axial width of the seal member 10 is also formed thick, the durability of the seal member 10 is improved. To do.

  Further, both the space portion S and the communication groove 22 have a large cross-sectional area of the passage communicating from the pump body side passage portion 18 to the axial grooves 23, and a large amount of the axial grooves 23 is formed in the axial grooves 23. Therefore, the width and thickness h of the space S can be reduced. That is, even if the width and thickness t of the seal plate 9 is made thicker than before, the increase in thickness can be suppressed to a small extent. Accordingly, the axial thickness of the entire pump due to the width and thickness t of the seal plate 9 does not increase greatly.

  Further, since each of the axial grooves 23 is formed by a relatively shallow groove on the outer periphery of the cam ring 5, it does not affect the rigidity of the cam ring 5.

  Further, since at least two of the axial grooves 23 are provided adjacent to the communication groove 22, the cross-sectional area of the communication path is formed to be large. A large amount of hydraulic oil can be supplied.

  FIG. 6 shows a second embodiment of the present invention, and the basic configuration is substantially the same as that of the first embodiment, except that the suction port 2c and each axial direction are provided inside the pump body 2. A second suction passage 24 that communicates with the groove 23 is formed.

  The second suction passage 24 is formed so that one end opening thereof opens to the suction port 2c of the pump body 2 and penetrates through each of the axial grooves 23 radially inward from the one end opening.

  That is, a part of the hydraulic oil supplied to the suction port 2 c flows directly into the partial axial grooves 23 by the second suction passage 24, and the plate member side suction ports 15 and 15, the flow amount of the hydraulic oil flowing into the plate member side suction ports 15 and 15 further increases.

  Therefore, the supply amount of the hydraulic oil supplied into the pump chambers P from the plate member-side suction ports 15 and 15 is increased, thereby reliably preventing a reduction in pump suction efficiency at the time of high pump rotation. Can do.

  As shown in FIG. 7, a plurality of axially extending portions are formed on the inner peripheral surface of the recess 2 a of the pump body 2 at positions corresponding to the axial grooves 23 formed on the outer peripheral surface of the cam ring 5. The axial groove portion 25 is formed. For this reason, a substantially circular communication path is formed to increase the cross-sectional area, and the hydraulic oil flowing into the plate member side suction ports 15 and 15 from the space S and the communication groove 22 is introduced. The amount increases.

  Therefore, the inflow amount of the hydraulic oil supplied from the plate member side suction ports 15 and 15 into the pump chambers P can be further increased.

  The present invention is not limited to the configuration of the previous embodiment. For example, the shafts 23 are not formed on the outer periphery of the cam ring 5, and the shafts are formed on the inner periphery of the recess 2 a of the pump body 2. By forming the directional groove 25, a gap formed between each axial groove 25 and the outer peripheral surface of the cam ring 5 can be used as the communication path.

  Further, the present invention can be applied to devices other than the power steering device.

It is a fragmentary sectional view of the vane pump with which this invention is provided. It is an AA line sectional view of the vane pump of this embodiment. (A) is the front view by which a part of cam ring provided for the 1st Embodiment of this invention was fractured | ruptured. (B) is the BB sectional drawing of the cam ring provided to the 1st Embodiment of this invention. (A) is a front view of the plate member provided to the 1st Embodiment of this invention. (B) is a side view of the plate member provided for the first embodiment of the present invention. It is a principal part expanded sectional view of the seal plate with which the 1st Embodiment of this invention is provided. It is a fragmentary sectional view of the vane pump which shows the 2nd Embodiment of this invention. It is a front view of the vane pump which shows the axial direction groove part formed in the internal peripheral surface of the recessed part of a pump body. It is a fragmentary sectional view of the vane pump which shows the axial direction groove part formed in the internal peripheral surface of the recessed part of a pump body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Pump body 2a ... Concave part 3 ... Cover member 4 ... Drive shaft 5 ... Cam ring 6 ... Rotor 6a ... Slot 7 ... Vane 8 ... Plate member 9 ... Seal plate 10 ... Seal member 14 ... Cover member side suction port 15 ... Plate member Side suction port 16 ... Plate member side discharge port 17 ... Suction passage 18 ... Pump body side passage portion 19 ... Cover member side passage portion 22 ... Communication groove 23 ... Axial groove (communication passage)
S ... Space

Claims (5)

A pump body having a recess opening on one side;
A cover member disposed on one side of the pump body to close the recess;
A drive shaft rotatably supported by the pump body and the cover member;
A cam ring disposed on the inner peripheral side of the recess;
A rotor disposed on the inner peripheral side of the cam ring and fixed to the drive shaft;
A plurality of vanes provided in a plurality of slots formed in the rotor so as to be able to move in and out, and separating a plurality of pump chambers between the cam ring and the rotor;
A plate member disposed on the bottom side of the recess to hold the cam ring together with the cover member;
A cover member-side suction port formed in the cover member and opening in a region where the volumes of the plurality of pump chambers increase; a cover member-side discharge port opening in a region where the volumes of the plurality of pump chambers decrease;
A plate member-side suction port that is formed in the plate member and opens to a region where the volumes of the plurality of pump chambers increase; and a plate member-side discharge port that opens to a region where the volumes of the plurality of pump chambers decrease;
A suction passage formed from the pump body to the cover member and communicating with the cover member-side suction port;
A seal plate interposed between the pump body and the cover member, and a seal member integrally fixed to the inner periphery,
A space portion that communicates with the suction passage is formed on the inner circumferential side of the seal member, and the communication passage that communicates the space portion with the plate member-side suction port is defined as an inner circumferential surface of the recess and an outer circumferential surface of the cam ring. A vane pump characterized by being formed between. 2. The vane pump according to claim 1, wherein the communication path is configured by a groove extending in an axial direction on an outer peripheral surface of the cam ring. 3. The vane pump according to claim 1, wherein a part of the outer peripheral edge of the plate member is cut out to extend the plate member side suction port outward in the radial direction. The vane pump according to any one of claims 1 to 3, wherein a communication groove for communicating the suction passage and the recess is formed in a side portion on one side of the pump body. The vane pump according to any one of claims 1 to 4, wherein a second suction passage communicating with the communication passage from a suction port formed in the pump body is formed.

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