JP2016223394A - Vane pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vane pump that can immediately build up discharge pressure in starting up a pump.SOLUTION: The vane pump includes an annular guide groove 43 formed at an inside surface of at least one of a body-side side plate and a cover-side side plate and communicating adjacent back pressure chambers 5 with each other. A vane 3 has a projection 3c stored in the guide groove 43. The projection 3c moves in the guide groove 43 with the rotation of a rotor 2 so that a tip 3a of the vane 3 moves while being in proximity to an inner peripheral cam surface 4a.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vane pump.

  In Patent Document 1, a plurality of slits are radially formed in the rotor at equal angular intervals on the circumference, and a plurality of vanes whose tip surfaces are in sliding contact with the cam surface of the cam ring are slidably accommodated in each slit. The invention of the vane pump is described. In the vane pump described in Patent Document 1, discharged oil is introduced into the inner end of the slit via a back pressure groove, and the vane is pressed against the cam surface of the cam ring by the discharged oil. Further, both ends of these vanes are in sliding contact with the side plate and the side surface of the rear housing. Thus, a plurality of pump chambers are formed by the adjacent vanes between the cam surface of the cam ring and the rotor.

JP 2001-280263 A

  However, in the vane pump disclosed in Patent Document 1, the pump discharge pressure is low when the pump is started, and the pressure introduced into the inner end of the slit is also low. For this reason, when starting the pump, the vane cannot be sufficiently pushed out toward the cam surface of the cam ring by the discharge pressure of the pump. In particular, when the vane pump is installed so that the rotation shaft is in the horizontal direction, when the rotation of the rotor is stopped, the vane at the top of the rotor is lowered to the back of the slit by gravity. When the pump is started in this state, since the pressure introduced to the inner end of the slit is low, the vane is not sufficiently pushed toward the cam surface of the cam ring, resulting in a large gap between the vane and the cam ring cam surface. The rotor rotates. For this reason, even if the volume of the pump chamber is reduced in the discharge stroke, part of the hydraulic oil in the pump chamber is not discharged but leaks to the adjacent pump chamber. Therefore, a certain time is required until the discharge pressure of the pump reaches a predetermined pressure.

   The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vane pump that can quickly raise the discharge pressure when the pump is started.

  According to a first aspect of the present invention, there is provided a rotor that is rotationally driven, slits that are radially formed with openings on the outer periphery of the rotor, vanes that are slidably accommodated for each slit, and the vanes from the slits. A cam ring having an inner circumferential cam surface that is in sliding contact with a tip of a vane that is an end in a protruding direction, a first side member that is provided on one end side in the axial direction of the rotor and that contacts the rotor and the cam ring, and an axial direction of the rotor A second side member that is provided on the other end side and abuts against the rotor and the cam ring; a pump chamber defined between the rotor and the vane adjacent to the cam ring; and a suction port that guides the working fluid sucked into the pump chamber; The discharge port that guides the working fluid discharged from the pump chamber and the base end of the vane that is the end opposite to the tip in the slit are discharged from the discharge port. A back pressure chamber into which a part of the working fluid is guided, and an annular guide groove formed on the inner surface of at least one of the first side member and the second side member, and the vane is fitted into the guide groove. A protrusion is provided, and the protrusion moves in the guide groove as the rotor rotates, so that the tip of the vane moves in a state of being close to the inner peripheral cam surface.

  In the first invention, the convex portion of the vane moves in the guide groove with the rotation of the rotor, so that the tip of the vane moves in a state of being close to the inner peripheral cam surface. Thereby, it is suppressed that the hydraulic fluid of the pump chamber in a discharge stroke leaks to the adjacent pump chamber.

  The second invention is characterized in that a gap exists between the tip of the vane and the inner peripheral cam surface of the cam ring in a state where the convex portion of the vane is in contact with the inner peripheral side wall of the guide groove.

  In the second invention, a certain degree of error is allowed in processing the inner peripheral side wall, and high processing accuracy is not required. Therefore, the guide groove can be easily processed.

  According to a third aspect of the present invention, the convex portion of the vane is configured not to contact the side wall on the outer peripheral side of the guide groove when the tip of the vane is in contact with the inner peripheral cam surface of the cam ring. .

  In the third invention, even if the vane is pushed out toward the inner peripheral cam surface of the cam ring by the pressure of the hydraulic oil supplied to the back pressure chamber, the convex portion of the vane does not contact the outer peripheral side wall of the guide groove. . Therefore, since the load is not applied to the convex portion, the convex portion can be prevented from being damaged.

  According to the present invention, the discharge pressure can be quickly raised when the pump is started.

It is sectional drawing of the vane pump which concerns on embodiment of this invention. It is a top view which shows the principal part of the vane pump in the state which removed the cover side side plate of the vane pump which concerns on embodiment of this invention. It is a top view of the body side side plate in the vane pump concerning the embodiment of the present invention. It is a top view of the cover side plate in the vane pump concerning the embodiment of the present invention. It is a top view of the vane in the vane pump concerning the embodiment of the present invention.

  Hereinafter, a vane pump 100 according to an embodiment of the present invention will be described with reference to the drawings.

  The vane pump 100 is used as a fluid pressure supply source for a fluid pressure device mounted on a vehicle, for example, a power steering device or a continuously variable transmission. The working fluid is oil or other water-soluble alternative liquid.

  As shown in FIGS. 1 and 2, the vane pump 100 includes a pump body 10 having a pump housing recess 10A, a pump cover 20 that covers the pump housing recess 10A and is fixed to the pump body 10, and the pump body 10 and the pump. A drive shaft 1 rotatably supported on the cover 20 via bearings 11 and 12, a rotor 2 connected to the drive shaft 1 and accommodated in the pump accommodating recess 10 </ b> A, and an opening 2 a on the outer periphery of the rotor 2. A plurality of slits 2A formed radially, a vane 3 slidably accommodated in each slit 2A, an inner peripheral cam surface 4a in which the rotor 2 and the vane 3 are accommodated and the tip 3a of the vane 3 is in sliding contact. A cam ring 4.

  The vane pump 100 is driven by, for example, an engine (not shown) or the like, and the rotor 2 coupled to the drive shaft 1 is driven to rotate clockwise as indicated by an arrow in FIG. 2 to generate fluid pressure.

  The vane 3 is slidably inserted into each slit 2A, and includes a distal end portion 3a that is an end portion in a direction protruding from the slit 2A, and a proximal end portion 3b that is an end portion opposite to the distal end portion 3a. Have. On the bottom side of the slit 2 </ b> A, a back pressure chamber 5 is formed which is partitioned by the base end portion 3 b of the vane 3 and into which hydraulic oil as a working fluid is guided. The vane 3 is pressed in a direction protruding from the slit 2 </ b> A by the pressure of the back pressure chamber 5.

  The cam ring 4 is an annular member having an inner circumferential cam surface 4a that is a substantially oval inner circumferential surface. When the vane 3 is pressed in a direction protruding from the slit 2 </ b> A by the pressure of the back pressure chamber 5, the tip 3 a of the vane 3 is in sliding contact with the inner peripheral cam surface 4 a of the cam ring 4. As a result, a pump chamber 6 is defined in the cam ring 4 by the outer peripheral surface of the rotor 2, the inner peripheral cam surface 4 a of the cam ring 4, and the adjacent vane 3.

  Since the inner peripheral cam surface 4a of the cam ring 4 has a substantially oval shape, the volume of the pump chamber 6 defined by the vanes 3 that are in sliding contact with the inner peripheral cam surface 4a as the rotor 2 rotates is expanded and contracted. And repeat. The hydraulic oil is sucked in the suction area where the pump chamber 6 expands, and the hydraulic oil is discharged in the discharge area where the pump chamber 6 contracts.

  As shown in FIG. 2, the vane pump 100 includes a first suction region where the vane 3 reciprocates for the first time, a first discharge region, and a second suction region where the vane 3 reciprocates for the second time, A second ejection region. The pump chamber 6 expands in the first suction region, contracts in the first discharge region, expands in the second suction region, and rotates into the second discharge region while the rotor 2 rotates once. Shrink. The vane pump 100 has two suction regions and two discharge regions, but is not limited thereto, and may have a configuration having one or three or more suction regions and one or three or more discharge regions.

  The vane pump 100 is provided on one end side in the axial direction of the rotor 2, and is provided on the body side side plate 30 as a first side member that contacts one side surface of the rotor 2 and the cam ring 4, and on the other end side in the axial direction of the rotor 2. And a cover side plate 40 as a second side member that contacts the other side surface of the rotor 2 and the cam ring 4.

  The body side plate 30 is provided between the bottom surface of the pump housing recess 10 </ b> A and the rotor 2. The rotor 2 is in sliding contact with the body side plate 30 and the cam ring 4 is in contact therewith. The cover side plate 40 is provided between the rotor 2 and the pump cover 20. The rotor 2 is in sliding contact with the cover side plate 40 and the cam ring 4 is in contact therewith. In this way, the body side plate 30 and the cover side plate 40 are disposed so as to face both side surfaces of the rotor 2 and the cam ring 4.

  The body side plate 30, the rotor 2, the cam ring 4, and the cover side plate 40 are housed in the pump housing recess 10 </ b> A of the pump body 10. In this state, the pump housing recess 10 </ b> A is sealed by attaching the pump cover 20 to the pump body 10.

  An annular high-pressure chamber 14 defined by the pump body 10 and the body side plate 30 is formed on the bottom side of the pump housing recess 10 </ b> A of the pump body 10. The high pressure chamber 14 communicates with a fluid pressure device 70 outside the vane pump 100 through the discharge passage 62. On the inner peripheral surface of the pump housing recess 10 </ b> A, a bypass passage 13 that is formed in the pump cover 20 and communicates with the suction pressure chamber 21 connected to the tank 60 through the suction passage 61 is provided. Two bypass passages 13 are provided at positions facing each other across the cam ring 4.

  As shown in FIG. 3, the body-side side plate 30 is formed on the sliding contact surface 30a so as to correspond to the sliding contact surface 30a on which the side surface of the rotor 2 slides and the first and second discharge regions, respectively. A discharge port 31 through which the hydraulic oil 6 is discharged, a through hole 32 through which the drive shaft 1 is inserted, and a suction recess 33 formed at a position corresponding to the bypass passage 13 provided in the inner peripheral surface of the pump housing recess 10A. And comprising.

  Two discharge ports 31 are provided at positions facing each other across the through hole 32. Each discharge port 31 is formed in an arc shape with the through hole 32 as the center. The discharge port 31 passes through the body side plate 30 and communicates with the high pressure chamber 14 formed in the pump body 10. The hydraulic oil that has flowed into the high-pressure chamber 14 is supplied to the fluid pressure device 70 outside the vane pump 100 through the discharge passage 62 (see FIG. 1).

  The suction recess 33 is formed on the sliding contact surface 30a so as to correspond to the first and second suction regions. The outer peripheral edge of each suction recess 33 reaches the outer peripheral surface of the body side plate 30 and is formed to have a concave shape that opens radially outward.

  An outer notch 36 and an inner notch 37, which are grooves extending from the discharge port 31 toward the rear in the rotation direction of the rotor 2, are formed on the sliding contact surface 30 a of the body side plate 30. The outer notch 36 is disposed on the outer peripheral side of the inner notch 37 and is formed so that the length in the rotation direction of the rotor 2 is longer than the inner notch 37.

  Both the outer notch 36 and the inner notch 37 are formed in a tapered shape in which the dimension in the radial direction of the rotor 2 decreases from the discharge port 31 toward the rear in the rotation direction of the rotor 2. Further, the outer notch 36 and the inner notch 37 are disposed on the outer peripheral side of the outer peripheral surface of the rotor 2 and on the inner peripheral side of the inner peripheral cam surface 4 a of the cam ring 4.

  The body side plate 30 has a pair of first back pressure grooves 34 formed on the sliding contact surface 30a so as to face each other across the through hole 32, and a pair of first back pressure grooves 34 formed on the sliding contact surface 30a. And a pair of second back pressure grooves 35 provided at positions displaced by approximately 90 ° with respect to the through hole 32 as a center.

  The first back pressure groove 34 is formed in an arc shape with the through hole 32 as the center, and communicates with the back pressure chamber 5. The first back pressure groove 34 communicates the plurality of back pressure chambers 5 opened to the first back pressure groove 34. Further, the first back pressure groove 34 communicates with a communication hole 38 formed through the body side plate 30. Thereby, the first back pressure groove 34 communicates with the high pressure chamber 14 through the communication hole 38 (see FIG. 1). The second back pressure groove 35 is formed in an arc shape centering on the through hole 32 and communicates with the back pressure chamber 5. The second back pressure groove 35 communicates the plurality of back pressure chambers 5 opened to the second back pressure groove 35.

  As shown in FIG. 4, the cover-side side plate 40 is formed so as to cut out a part of the outer edge, and a suction port 41 that guides hydraulic oil into the pump chamber 6 and a discharge port 31 of the body-side side plate 30. , A discharge recess 42 formed at a position corresponding to the above, an annular guide groove 43 formed in the sliding contact surface 40a in a shape substantially similar to the inner peripheral cam surface 4a of the cam ring 4, and a through hole through which the drive shaft 1 is inserted. 44.

  The suction port 41 is formed at a position corresponding to the first and second suction areas. Each suction port 41 is formed in an arc shape centering on the through hole 44. The suction port 41 communicates with the tank 60 through a suction pressure chamber 21 formed in the pump cover 20.

  The discharge recess 42 is formed in a groove shape and is formed in each of the first and second discharge regions. Each discharge recess 42 is formed in an arc shape centering on the through hole 44. Since the discharge recess 42 communicates with the discharge port 31 through the pump chamber 6, the same pressure as the discharge port 31 acts on the discharge recess 42. Since the discharge recess 42 is provided so as to face the discharge port 31 with the vane 3 interposed therebetween, the force acting on the vane 3 due to the pressure in the discharge port 31 is offset by the pressure of the discharge recess 42. Thereby, it is possible to prevent the vane 3 from being pressed against the cover side plate 40 by the pressure in the discharge port 31.

  The guide groove 43 is formed such that the radial distance of the rotor 2 from the inner peripheral side wall 43a of the guide groove 43 to the inner peripheral cam surface 4a of the cam ring 4 is substantially constant. The guide groove 43 is formed so as to communicate with the adjacent back pressure chambers 5. As a result, the back pressure chamber 5 of each vane 3 communicates with the guide groove 43.

  As shown in FIGS. 1 and 5, the vane 3 has a convex portion 3 c that is formed so as to protrude from the end surface 3 d that is in sliding contact with the cover-side side plate 40 and is accommodated in the guide groove 43. When the vane 3 rotates together with the rotor 2, the convex portion 3 c moves along the guide groove 43 in the guide groove 43.

  The convex portion 3 c is formed on the base end portion 3 b side of the vane 3. Further, the length L1 of the protrusion 3c in the width direction of the guide groove 43 is formed to be smaller than the width La of the guide groove 43. Further, the length L2 from the end surface 3e on the inner peripheral cam surface 4a side of the convex portion 3c to the tip end portion 3a is set from the outer peripheral side wall 43b of the guide groove 43 in the radial direction of the rotor 2 to the inner peripheral cam surface 4a of the cam ring 4. It is formed to be larger than the distance up to. Thus, the convex portion 3c of the vane 3 is configured not to contact the outer peripheral side wall 43b of the guide groove 43 in a state where the tip 3a of the vane 3 is in contact with the inner peripheral cam surface 4a of the cam ring 4. Is done.

  The convex part 3 c of the vane 3 maintains a state in which the tip part 3 a of the vane 3 is close to the inner peripheral cam surface 4 a of the cam ring 4 when the convex part 3 c contacts the side wall 43 a on the inner peripheral side of the guide groove 43. The guide groove 43 is configured to be movable in the radial direction of the rotor 2 as much as possible.

  Next, the operation of the vane pump 100 will be described.

  When the drive shaft 1 is rotationally driven by the power of a drive device such as an engine (not shown), the rotor 2 rotates in the direction indicated by the arrow in FIG. As the rotor 2 rotates, the pump chamber 6 located in the first and second suction regions expands. As a result, the hydraulic oil in the tank 60 is sucked into the pump chamber 6 through the suction passage 61, the suction pressure chamber 21, the suction port 41, and the suction recess 33 as indicated by arrows in FIG. 1. Further, the pump chamber 6 located in the first and second discharge regions contracts as the rotor 2 rotates. Thereby, the hydraulic oil in the pump chamber 6 is discharged to the high-pressure chamber 14 through the discharge port 31. The hydraulic oil discharged to the high pressure chamber 14 is supplied to the external fluid pressure device 70 through the discharge passage 62. In the vane pump 100, each pump chamber 6 repeats suction and discharge of hydraulic oil twice while the rotor 2 rotates once.

  Part of the hydraulic oil discharged to the high pressure chamber 14 is supplied to the back pressure chamber 5 through the communication hole 38 and the first back pressure groove 34, and presses the base end portion 3b of the vane 3 toward the inner peripheral cam surface 4a. To do. Therefore, the vane 3 is urged in the direction protruding from the slit 2 </ b> A by the fluid pressure of the back pressure chamber 5 that presses the base end portion 3 b and the centrifugal force that works as the rotor 2 rotates. As a result, the tip 3 a of the vane 3 rotates while being in sliding contact with the inner peripheral cam surface 4 a of the cam ring 4. From the discharge port 31 without leakage.

  The hydraulic oil supplied from the first back pressure groove 34 to the back pressure chamber 5 is supplied to the guide groove 43 through the back pressure chamber 5. At this time, the adjacent back pressure chambers 5 communicate with each other through the guide groove 43. Adjacent back pressure chambers 5 communicate with each other through a first back pressure groove 34 and a second back pressure groove 35. Thereby, the hydraulic oil discharged to the high pressure chamber 14 is supplied to each back pressure chamber 5. Accordingly, all the vanes 3 of the vane pump 100 rotate while the tip end portion 3 a is in sliding contact with the inner peripheral cam surface 4 a of the cam ring 4.

  In a general vane pump, when the rotation stops, the pressure in the high pressure chamber 14 and the back pressure chamber 5 decreases. Even if the vane pump is started again in this state, the pressure of the hydraulic oil supplied to the back pressure chamber 5 is low because the discharge pressure of the vane pump is low at the start. Therefore, when the vane pump is started, the pressure of the hydraulic oil supplied to the back pressure chamber 5 cannot sufficiently push the vane 3 toward the inner peripheral cam surface 4 a of the cam ring 4. For this reason, there is a possibility that a gap is generated between the tip 3 a of the vane 3 and the inner peripheral cam surface 4 a of the cam ring 4. In particular, when the vane pump is installed so that the drive shaft 1 is in the horizontal direction, when the vane pump stops, the vane 3 at the upper part of the rotor 2 falls to the back of the slit 2A due to gravity. Even if the vane pump is started in this state, the vane 3 is not sufficiently pushed out toward the inner peripheral cam surface 4a as described above. For this reason, the rotor 2 rotates with a large gap formed between the vane 3 and the inner peripheral cam surface 4a. Thereby, even if the volume of the pump chamber 6 is reduced in the discharge stroke, a part of the hydraulic oil in the pump chamber 6 is not discharged, but leaks to the adjacent pump chamber 6 at the rear in the rotation direction of the rotor 2. .

  However, the vane pump 100 of this embodiment is configured such that the convex portion 3 c of the vane 3 is accommodated in the guide groove 43, and the convex portion 3 c moves in the guide groove 43 as the rotor 2 rotates. Accordingly, when the vane pump 100 is stopped, even if the vane 3 at the top of the rotor 2 tries to move to the back of the slit 2A due to gravity, the convex portion 3c comes into contact with the side wall 43a on the inner peripheral side of the guide groove 43. 3 is maintained close to the inner peripheral cam surface 4 a of the cam ring 4. Therefore, when the vane pump 100 is restarted, the pressure of the hydraulic oil supplied to the back pressure chamber 5 is low, and even if the force pushing the vane 3 toward the inner peripheral cam surface 4a of the cam ring 4 is weak, the vane 3 The tip portion 3a can move along the inner peripheral cam surface 4a in a state of being close to the inner peripheral cam surface 4a. Therefore, it is possible to suppress leakage of hydraulic oil from the pump chamber 6 whose volume is reduced in the discharge stroke to the adjacent pump chamber 6. Thereby, the discharge pressure of the vane pump 100 can be quickly raised at the start of the pump.

  According to the above embodiment, there exist the effects shown below.

  The vane pump 100 moves in a state in which the tip 3a of the vane 3 is close to the inner peripheral cam surface 4a as the convex portion 3c of the vane 3 moves in the guide groove 43 as the rotor 2 rotates. Thus, even when the pressure of the hydraulic oil supplied to the back pressure chamber 5 at the time of starting the pump is low, the rotor 2 rotates with the tip 3a of the vane 3 close to the inner peripheral cam surface 4a. Leakage from the pump chamber 6 whose volume is reduced in the discharge stroke can be suppressed. Thereby, the discharge pressure of the vane pump 100 can be quickly raised at the start of the pump.

  Moreover, in the vane pump 100, the convex part of the vane 3 moves in the guide groove 43, so that the state where the tip part 3a of the vane 3 is close to the inner peripheral cam surface 4a can be maintained. For this reason, the distance which moves because the front-end | tip part 3a of the vane 3 contact | abuts to the inner peripheral cam surface 4a may be small. As a result, the vane 3 can be brought into contact with the cam ring 4 even with a small centrifugal force at a low rotational speed immediately after starting.

  Further, in the vane pump 100, part of the hydraulic oil discharged from the discharge port 31 is supplied to the back pressure chamber 5 through the high pressure chamber 14, the communication hole 38, the first back pressure groove 34, and the guide groove 43. Thereby, the front-end | tip part 3a of the vane 3 is pressed toward the inner peripheral cam surface 4a. Thus, during steady operation, the hydraulic oil in the pump chamber 6 can be prevented from leaking from between the tip 3a of the vane 3 and the inner peripheral cam surface 4a of the cam ring 4, so that the efficiency of the vane pump 100 is improved.

  In the vane pump 100, the back pressure chambers 5 adjacent to each other are communicated with each other by the guide groove 43. That is, the guide groove 43 has a function as a communication path for communicating the back pressure chambers 5 in addition to the function of guiding the convex portion 3 c of the vane 3. Therefore, it is not necessary to provide a separate communication path for communicating the back pressure chambers 5 on the sliding contact surface 40a of the cover side plate 40 or the side surface of the rotor 2, and therefore the processing of the vane pump 100 can be reduced.

  In the vane pump 100, it is desirable to form the side wall 43a on the inner peripheral side of the guide groove 43 so that the tip 3a of the vane 3 is always in contact with the inner peripheral cam surface 4a of the cam ring 4. However, in such a configuration, precise processing is required to process the guide groove 43 into such a shape. Further, when the vane 3 or the cam ring 4 expands or contracts due to a heat change, the convex portion 3c or the tip portion 3a of the vane 3 may be deformed or damaged.

  For this reason, in the vane pump 100, when the convex portion 3 c of the vane 3 is in contact with the inner peripheral side wall 43 a of the guide groove 43, there is a gap between the tip portion 3 a of the vane 3 and the inner peripheral cam surface 4 a of the cam ring 4. May be present. Thereby, a certain amount of error is allowed in processing the inner peripheral side wall 43a, and high processing accuracy is not required. Therefore, the processing of the guide groove 43 can be simplified. Further, when the vane 3 or the cam ring 4 expands or contracts due to a heat change, the deformation of the vane 3 or the cam ring 4 can be absorbed by the gap, so that the convex part 3c or the tip part 3a of the vane 3 is damaged or deformed. There is nothing to do. Furthermore, the vane pump 100 can be easily assembled because it is not necessary to precisely align the positions of the members.

  Further, in the vane pump 100, the convex portion 3c of the vane 3 does not contact the side wall 43b on the outer peripheral side of the guide groove 43 in a state where the tip portion 3a of the vane 3 is in contact with the inner peripheral cam surface 4a of the cam ring 4. Composed. Thereby, even if the vane 3 is pushed toward the inner peripheral cam surface 4 a of the cam ring 4 by the pressure of the hydraulic oil supplied to the back pressure chamber 5, the convex portion 3 c is formed on the outer side wall 43 b of the guide groove 43. Do not touch. Therefore, since the load is not applied to the convex part 3c, it can prevent that the convex part 3c is damaged.

  The configuration, operation, and effect of the embodiment of the present invention configured as described above will be described together.

  The vane pump 100 includes a rotor 2 that is rotationally driven, a plurality of slits 2A that are radially formed with openings 2a on the outer periphery of the rotor 2, and vanes 3 that are slidably received in the slits 2A. The cam ring 4 having the inner circumferential cam surface 4a with which the tip 3a of the vane 3 is slidably contacted, and the first side member (body-side side plate 30) that is provided on one end side in the axial direction of the rotor 2 and contacts the rotor 2 and the cam ring 4 Between the rotor 2 and the cam ring 4 and the vane 3 adjacent to the rotor 2 and the cam ring 4. A defined pump chamber 6, a suction recess 33 and a suction port 41 for guiding hydraulic oil to the pump chamber 6, a discharge port 31 for guiding hydraulic oil discharged from the pump chamber 6, and a slipper 2A, a back pressure chamber 5 partitioned by a base end portion 3b of the vane 3 and guided by a part of hydraulic oil discharged from the discharge port 31, a first side member (body side plate 30) and a second side An annular guide groove 43 formed on at least one inner surface of the member (the cover-side side plate 40) and communicating with the adjacent back pressure chamber 5, and the vane 3 has a convex portion 3c accommodated in the guide groove 43. And the protrusion 3c moves in the guide groove 43 as the rotor 2 rotates, so that the tip 3a of the vane 3 moves in a state of being close to the inner peripheral cam surface 4a.

  According to this configuration, the protrusion 3c of the vane 3 moves in the guide groove 43 as the rotor 2 rotates, so that the tip 3a of the vane 3 moves in a state of being close to the inner peripheral cam surface 4a. Thereby, it is suppressed that the hydraulic fluid of the pump chamber 6 in a discharge stroke leaks to the adjacent pump chamber 6. Therefore, the discharge pressure can be quickly raised when the vane pump 100 is started.

  In the vane pump 100, when the convex portion 3 c of the vane 3 is in contact with the inner peripheral side wall 43 a of the guide groove 43, a gap exists between the tip portion 3 a of the vane 3 and the inner peripheral cam surface 4 a of the cam ring 4. .

  In this configuration, a certain amount of error is allowed in processing the inner peripheral side wall 43a, and high processing accuracy is not required. Therefore, the processing of the guide groove 43 can be simplified.

  In the vane pump 100, the convex portion 3c of the vane 3 is configured not to contact the side wall 43b on the outer peripheral side of the guide groove 43 in a state where the tip 3a of the vane 3 is in contact with the inner peripheral cam surface 4a of the cam ring 4. The

  In this configuration, even if the vane 3 is pushed toward the inner peripheral cam surface 4 a of the cam ring 4 by the pressure of the hydraulic oil supplied to the back pressure chamber 5, the convex portion 3 c of the vane 3 is on the outer peripheral side of the guide groove 43. It does not contact the side wall 43b. Therefore, since the load is not applied to the convex part 3c, it can prevent that the convex part 3c is damaged.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  For example, in the vane pump 100, the guide groove 43 is provided in the cover side plate 40, but may be provided in the body side plate 30. The guide groove 43 may be provided in the body side plate 30 and the cover side plate 40. Further, the vane pump 100 may not include the cover side plate 40. In this case, a guide groove 43 is formed in the pump cover 20.

  The guide groove 43 is formed in a substantially similar shape to the inner peripheral cam surface 4a of the cam ring 4, but if the inner peripheral side wall 43a is substantially similar in shape, the outer peripheral side wall 43b has any shape. May be.

  100 ... Vane pump, 1 ... drive shaft, 2 ... rotor, 2a ... opening, 2A ... slit, 3 ... vane, 3a ... tip, 3b ... base End part, 3c ... convex part, 4 ... cam ring, 4a ... inner peripheral cam surface, 5 ... back pressure chamber, 6 ... pump chamber, 10 ... pump body, 10A ... Pump housing recess, 13 ... detour passage, 14 ... high pressure chamber, 20 ... pump cover, 21 ... suction pressure chamber, 30 ... body side plate, 31 ... discharge port, 33 ... Suction recess, 40 ... Cover side plate, 41 ... Suction port, 42 ... Discharge recess, 43 ... Guide groove, 43a ... Inner peripheral side wall, 43b ... Outer peripheral side wall, 60 ... tank, 61 ... suction passage, 62 ... discharge passage, 70 ... fluid pressure device

Claims (3)

A vane pump used as a fluid pressure supply source,
A rotor that is driven to rotate;
A plurality of slits formed radially with openings on the outer periphery of the rotor;
Vanes that are slidably received in the slits;
A cam ring having an inner circumferential cam surface with which the tip of the vane is in sliding contact;
A first side member provided on one end side in the axial direction of the rotor and in contact with the rotor and the cam ring;
A second side member provided on the other axial end of the rotor and in contact with the rotor and the cam ring;
A pump chamber defined between the rotor and the vane adjacent to the cam ring;
A suction port for guiding the working fluid to the pump chamber;
A discharge port through which a working fluid discharged from the pump chamber is guided;
A back pressure chamber partitioned by the base end portion of the vane in the slit and guided by a part of the working fluid discharged from the discharge port;
An annular guide groove formed on the inner surface of at least one of the first side member and the second side member and communicating with the adjacent back pressure chamber;
The vane has a convex portion received in the guide groove,
The vane pump, wherein the convex portion moves in the guide groove as the rotor rotates, so that the tip portion of the vane moves in a state of being close to the inner circumferential cam surface.   In the state where the convex part of the vane is in contact with the inner peripheral side wall of the guide groove, a gap exists between the tip part of the vane and the inner peripheral cam surface of the cam ring. The vane pump according to claim 1.   The convex portion of the vane is configured not to contact an outer peripheral side wall of the guide groove in a state where the tip end portion of the vane is in contact with the inner peripheral cam surface of the cam ring. The vane pump according to claim 1 or 2.

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