JP2007255276A - Variable displacement vane pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable displacement vane pump improving a delivery response delay. <P>SOLUTION: This variable displacement vane pump has a cam ring forming a plurality of pump rooms on the inner peripheral side together with a rotor and a vane, a first member and a second member arranged on both sides in the axial direction of the cam ring, a suction port arranged on at least one side of the first member or the second member and opening in an area of increasing the volume of the plurality of pump rooms, a delivery port opening in an area of reducing the volume of the plurality of pump rooms, a seal member arranged on the outer peripheral side of the cam ring and defining an outer peripheral side space of the cam ring into a first fluid pressure chamber arranged in the direction increasing a pump delivery quantity and a second fluid pressure chamber arranged in the direction reducing the pump delivery quantity, and a control valve controlling only hydraulic pressure of the second fluid pressure chamber. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a variable displacement vane pump for a power steering apparatus.

Conventionally, in the variable displacement vane pump described in Patent Document 1, the discharge amount is changed by the rocking displacement of a cam ring forming a pump chamber. The cam ring is controlled in its swing amount by the pressure difference between the first and second fluid pressure chambers formed on both sides, and the pressure in the first and second fluid pressure chambers is controlled by a control valve.
Japanese Patent Laid-Open No. 6-200883

  However, in the above prior art, when the discharge amount is increased, the pressure of the first fluid pressure chamber is discharged to the suction side to reduce the pressure, and the cam ring is controlled to swing to the first fluid pressure chamber side. Therefore, there is a problem that the high pressure is removed from the first fluid pressure chamber, and the time lag until the discharge amount increases is large and the discharge response is delayed. In particular, when a vane pump is used as a hydraulic power source of a power steering device, an increase in steering load based on response delay becomes significant.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a variable displacement vane pump with improved discharge response delay.

  In order to achieve the above object, according to the present invention, a pump body, a drive shaft pivotally supported by the pump body, a rotor provided in the pump body and driven to rotate by the drive shaft, and a circumference of the rotor A vane that is retractably accommodated in a plurality of slots provided in a direction, and is provided in the pump body so as to be swingable, and a plurality of pump chambers are formed on the inner peripheral side together with the rotor and the vane. Cam rings, first and second members provided on both sides of the cam ring in the axial direction, and at least one of the first member and the second member, and the volumes of the plurality of pump chambers increase. A suction port that opens to a region, a discharge port that opens to a region where the volume of the plurality of pump chambers is reduced, and an outer peripheral side of the cam ring. A seal member that divides the circumferential space into a first fluid pressure chamber provided in a direction in which the pump discharge amount increases and a second fluid pressure chamber provided in a direction in which the pump discharge amount decreases; And a control valve that controls only the hydraulic pressure of the fluid pressure chamber.

  Therefore, a variable displacement vane pump with improved discharge response delay can be provided.

  The best mode for carrying out the present invention will be described below based on the embodiments shown in the drawings.

[Outline of vane pump]
The first embodiment will be described with reference to FIGS. FIG. 1 is an axial sectional view of the vane pump 1, and FIGS. 2 and 3 are radial sectional views. FIG. 2 shows the case where the cam ring 4 is positioned in the most negative y-axis direction (maximum eccentricity), and FIG. 3 shows the case where the cam ring 4 is positioned in the most positive y-axis direction (minimum eccentricity).

  The axial direction of the drive shaft 2 is the x-axis, and the direction in which the drive shaft is inserted into the first and second housings 11 and 12 is the positive direction. Further, the axial direction of the spring 201 (see FIG. 2) that restricts the swing of the cam ring 4 and the direction in which the cam ring 4 is urged is the y-axis negative direction, the axis orthogonal to the x and y axes, and the intake port IN. The side is the z-axis positive direction.

  The vane pump 1 includes a drive shaft 2, a rotor 3, a cam ring 4, an adapter ring 5, and a pump body 10. The drive shaft 2 is connected to the engine via a pulley and rotates integrally with the rotor 3.

  A plurality of slots 31, which are axial grooves, are formed radially on the outer periphery of the rotor 3, and vanes 32 are inserted into the slots 31 so as to be able to protrude and retract in the radial direction. Further, a back pressure chamber 33 is provided at an inner diameter side end portion of each slot 31, and pressure oil is supplied to urge the vane 32 radially outward.

  The pump body 10 is formed of a first housing 11 and a second housing 12 (second member). The first housing 11 has a bottomed cup shape that opens to the positive side of the x-axis, and a disk-shaped side plate 6 (first member) is accommodated on the bottom 111. The adapter ring 5, the cam ring 4, and the rotor 3 are housed on the pump element accommodating portion 112 that is the inner peripheral portion of the first housing 11 and on the side of the side plate 6 in the positive x-axis direction.

  The second housing 12 is in liquid-tight contact with the adapter ring 5, the cam ring 4, and the rotor 3 from the x axis positive direction side, and the adapter ring 5, the cam ring 4, and the rotor 3 are sandwiched between the side plate 6 and the second housing 12. The Rukoto.

  Suction ports 62 and 121 and discharge ports 63 and 122 are provided on the x-axis positive side surface 61 of the side plate 6 and the x-axis negative direction surface 120 of the second housing 12, respectively, and are connected to the suction port IN and the discharge port OUtT. The hydraulic oil is supplied to and discharged from the pump chamber B formed between the rotor 3 and the cam ring 4.

  The adapter ring 5 is a substantially elliptical annular member having a major axis on the y-axis side and a minor axis on the z-axis side. The adapter ring 5 is accommodated in the first housing 11 on the outer peripheral side and the cam ring 4 on the inner peripheral side. To dispose. The adapter ring 5 is restricted from rotating with respect to the first housing 11 by the second seal member 40 so as not to rotate in the first housing 11 when the pump is driven.

  The cam ring 4 is a substantially perfect circular ring member, and the outer periphery thereof is provided with substantially the same diameter as the short axis of the adapter ring 5. Therefore, by being accommodated in the substantially elliptical adapter ring 5, a fluid pressure chamber A is formed between the inner periphery of the adapter ring 5 and the outer periphery of the cam ring 4, and the cam ring 4 extends in the y-axis direction within the adapter ring 5. It can swing.

  Further, a seal member 50 is provided at the end in the z-axis positive direction of the adapter ring inner peripheral surface 53, and a support surface N is formed at the end in the z-axis negative direction. The adapter ring 5 locks the cam ring 4 in the negative z-axis direction on the support surface N. A pin-shaped second seal member 40 is provided on the support surface N, and the fluid pressure chamber A between the cam ring 4 and the adapter ring 5 allows the fluid pressure chamber A between the cam ring 4 and the adapter ring 5 to be in the x-axis negative and positive directions. The first and second fluid pressure chambers A1 and A2 are formed.

  Here, since the cam ring 4 oscillates while rolling on the support surface N, the volume of each fluid pressure chamber A1, A2 changes, but the z-axis negative direction support surface N rotates clockwise about the y-axis as the origin. It is parallel to the ξ axis that is rotated to the right. That is, the support surface N is inclined to the z-axis negative direction side as it goes to the y-axis positive direction side, and the cam ring 4 is easily swung in the y-axis positive direction by the inclined support surface N.

  The outer diameter of the rotor 3 is smaller than the inner peripheral surface 41 of the cam ring, and is accommodated on the inner peripheral side of the cam ring 4. Even when the cam ring 4 swings and the relative position between the rotor 3 and the cam ring 4 changes, the outer periphery of the rotor 3 is provided so as not to contact the inner peripheral surface 41 of the cam ring.

  Further, when the cam ring 4 is positioned most in the y-axis negative direction due to the swing, the distance L between the cam ring inner peripheral surface 41 and the outer periphery of the rotor 3 is maximum on the y-axis negative direction side. When the cam ring 4 is positioned most in the y-axis positive direction, the distance L is similarly minimum on the y-axis positive direction side.

  Here, the radial length of the vane 32 is set to be larger than the maximum value of the distance L. Therefore, the vane 32 is always inserted into the slot 31 regardless of the relative position between the cam ring 4 and the rotor 3. The state in contact with the inner peripheral surface 41 is maintained. As a result, the vane 32 constantly receives the back pressure from the back pressure chamber 33 and comes into liquid tight contact with the cam ring inner peripheral surface 41.

  Therefore, the region between the cam ring 4 and the rotor 3 is always liquid-tightly defined by the adjacent vanes 32 to form the pump chamber B. If the rotor 3 and the cam ring 4 are in an eccentric state due to the swing, the volume of each pump chamber B changes as the rotor 3 rotates.

  The suction ports 62 and 121 and the discharge ports 63 and 122 provided in the side plate 6 and the second housing 12 are provided along the outer periphery of the rotor 3, and hydraulic oil is supplied and discharged by the volume change of each pump chamber B. .

  A radial through hole 51 is provided at the y-axis positive end of the adapter ring 5. Further, a plug member insertion hole 114 is provided at the end of the first housing 11 in the positive direction of the y axis, and a bottomed cup-shaped plug member 70 is inserted so as to be liquidtight with the outside of the first and second housings 11 and 12. Keep.

  A spring 201 is inserted into the inner periphery of the plug member 70 so as to be expandable and contractible in the y-axis direction, passes through the radial through hole 51 of the adapter ring 5 and abuts on the cam ring 4 and biases in the negative y-axis direction.

  The spring 201 urges the cam ring 4 in the direction in which the swing amount becomes maximum, and stabilizes the discharge amount (cam ring 4 swing position) at the time of pump start when the pressure is not stable.

  In this embodiment, the opening in the radial direction through hole 51 of the adapter ring 5 is used as a stopper for the cam ring 4 to restrict the swing in the positive y-axis direction. It is good also as a stopper by making it protrude in the inner peripheral side of the ring 5 (refer Example 2).

  The support surface N that supports the cam ring 4 of the pump body 10 includes a first intermediate point M1 between the end portions of the suction ports 62 and 121 and the start ends of the discharge ports 63 and 122, and the end portions of the discharge ports 63 and 122 and the suction port. With respect to a virtual line KK connecting the second intermediate point M2 with the start ends of the ports 62 and 121, the first fluid pressure chamber A1 side is gradually separated from the second fluid pressure chamber A2 side, and y It is formed so as to incline in the positive axis direction and the negative z axis direction.

  Therefore, when the phantom line KK is mounted horizontally when the vane pump 1 of the present application is mounted on the vehicle, the cam ring 4 easily sinks in the negative z-axis direction due to the action of the discharge pressure Pout in the pump chamber B. However, in the present application, since the support surface N is provided so that the position in the z-axis direction becomes lower in the yz plane in the positive direction of the y-axis, the support surface N resists high pressure with the maximum eccentricity of low rotation. N is increased in the z-axis direction, high rotation and small eccentricity and low pressure, the support surface N is lowered in the z-axis direction, and the sinking of the cam ring 4 in the negative z-axis direction is cancelled. Both regions suppress pulsation and noise.

[Supply of pressure oil to the first and second fluid pressure chambers]
A through hole 52 is provided on the z-axis positive direction side of the adapter ring 5 and on the y-axis positive direction side of the seal member 50. Each of the through holes 52 communicates with the control valve 7 via an oil passage 113 provided in the first housing 11, and connects the second fluid pressure chamber A <b> 2 on the y axis positive direction side and the control valve 7. The oil passage 113 opens into a valve housing hole 115 that accommodates the control valve 7, and the control pressure Pv is introduced into the second fluid pressure chamber A2 as the pump is driven.

  By providing the through hole 52 provided in the adapter ring 5 in the center of the axial width of the adapter ring 5, the outer peripheral surface of the adapter ring 5 becomes a sealing surface to reduce leakage.

  The control valve 7 is connected to the discharge ports 63 and 122 via the oil passages 21 and 22. An orifice 8 is provided on the oil passage 22, and a discharge pressure Pout that is an upstream pressure of the orifice 8 and a downstream pressure Pfb of the orifice 8 are introduced into the control valve 7. The control valve 7 is driven by the differential pressure between Pout and Pfb and the valve spring 7a to generate the control pressure Pv.

  Accordingly, the control pressure Pv is introduced into the second fluid pressure chamber A2, and the control pressure Pv is generated based on the suction pressure Pin and the discharge pressure Pout, so that the control pressure Pv ≧ the suction pressure Pin.

  On the other hand, the suction pressure Pin is introduced into the first fluid pressure chamber A1 through the communication groove 64. The communication groove 64 is a radial groove provided in the x-axis positive side surface 61 of the pressure plate 6 and communicates the suction port 62 and the outer periphery of the cam ring 4. Therefore, the first fluid pressure chamber A1 communicates with the suction port 62 by the communication groove 64, and the suction pressure Pin is always introduced.

  Accordingly, in the vane pump 1 of the present application, only the hydraulic pressure P2 of the second fluid pressure chamber A2 is controlled, and the hydraulic pressure P1 of the first fluid pressure chamber A1 is not controlled, and always P1 = suction pressure Pin. Compared with the case where both the pressures P1, P2 of the first and second fluid pressure chambers A1, A2 are controlled, pressure control and flow rate control are easier.

  The second housing 12 may be provided with a radial groove so that the suction ports 62 and 121 and the first fluid pressure chamber A1 communicate with each other without any particular limitation. Further, since the hydraulic oil discharged from the first fluid pressure chamber A1 by the communication groove 64 is returned to the suction ports 62 and 121, the suction efficiency is improved. Further, the communication groove 64 can be easily formed only by processing the surface of the pressure plate 6.

[Swing of cam ring]
The moment Mp that rotates the cam ring in the direction of small eccentricity is applied due to the offset between the resultant force Fp and the cam ring swing support point Na of the adapter ring 5 applied to the negative half (lower half) of the z-axis of the ring 4 where the internal pressure of the pump is bit. This is generated and becomes the urging force F1 in the positive y-axis direction. If F1 is it becomes greater than the sum F2 of the negative y-axis direction urging the force received from the pressure P2 and the spring 201 of the second fluid pressure chamber A2, the cam ring 4 is eccentric amount of the cam ring center Oc and rotor center O _R is small, The discharge amount of the pump decreases (FIG. 3).

When the pump discharge amount decreases, the flow rate from the discharge oil passage 22 through the orifice 8 decreases, the difference between Pfb and Pout which is the differential pressure across the orifice 8 decreases, the force of the valve spring 7a overcomes, and the valve becomes y The shaft P is moved in the negative direction (situation in FIG. 2), high pressure Pout is introduced to the control pressure Pv, and the pressure P2 in the second fluid pressure chamber A2 rises through the passage 52. When F1 and F2 increase, the cam ring 4 swings in the y-axis negative direction side.
By this swinging, the eccentric amount of the cam ring 4 increases and the discharge amount increases. When the flow rate increases, the differential pressure across the orifice 8 increases, the valve moves in the y-axis direction (FIG. 3), and the control pressure PV and the pressure P2 in the second fluid pressure chamber A2 decrease.

  When the urging forces F1 and F2 in the positive and negative directions of the y-axis become substantially equal, the forces in the y-axis direction acting on the cam ring 4 are balanced and the cam ring 4 stops. Therefore, the pump is controlled to maintain a predetermined flow rate.

  In this way, the control pressure Pv is introduced into the second fluid pressure chamber A2, and the first fluid pressure chamber A1 is always quickly released by the suction pressure Pin, so that the cam ring is highly responsive to the first fluid pressure chamber A1 side. To improve the responsiveness of the discharge amount control.

[Effect of Example 1]
(1) A pump body 10, a drive shaft 2 that is pivotally supported by the pump body 10, a rotor 3 that is provided in the pump body 10 and is driven to rotate by the drive shaft 2, and a plurality of them are provided in the circumferential direction of the rotor 3. Vane 32 accommodated in the slot 31 so as to be able to appear and retract, and a cam ring which is provided in the pump body 10 so as to be swingable and forms a plurality of pump chambers B together with the rotor 3 and the vanes 32 on the inner peripheral side. 4, the pressure plate 6 and the second housing 12 provided on both sides in the axial direction of the cam ring 4, and the pressure plate 6 or the second housing 12 are provided on at least one side to increase the volume of the plurality of pump chambers B. Suction ports 62 and 121 that open to the region, discharge ports 63 and 122 that open to the region where the volumes of the plurality of pump chambers B are reduced, and cams The first fluid pressure chamber A1 provided on the outer peripheral side of the ring 4 and provided in the direction in which the pump discharge amount increases in the outer peripheral side space of the cam ring 4, and the second fluid provided in the direction in which the pump discharge amount decreases. The seal member 50 that is separated from the pressure chamber A2 and the control valve 7 that controls only the hydraulic pressure of the second fluid pressure chamber A2 are provided.

  As a result, the suction pressure Pin is introduced into the first fluid pressure chamber A1 to maintain a low pressure, and when the discharge amount is increased, the pressure on the second fluid pressure chamber A2 side is increased, so that the cam ring 4 is moved to the first fluid pressure chamber A1. By swinging toward the fluid pressure chamber A1, the responsiveness of the discharge amount control can be improved.

  (2) A communication groove 64 for communicating the first fluid pressure chamber A1 and the suction ports 62 and 121 is further provided. As a result, the first fluid pressure chamber A1 sandwiching the cam ring 4 is connected to the suction ports 62 and 121, and the suction pressure Pin is introduced into the first fluid pressure chamber A1, thereby being discharged from the first fluid pressure chamber A1. Since the working oil is returned to the suction ports 62 and 121 side, the suction efficiency can be improved.

  (3) The communication groove 64 is the pressure plate 6 or the second housing 12 and is formed on the surface facing the cam ring 4. By forming the communication groove 64 on the surface of the pressure plate 6 or the second housing 12, the communication groove 64 can be easily formed.

  (4) (7) (11) The support surface N that supports the cam ring 4 is formed at the end of the suction ports 62 and 121 from the second seal member 40 of the swinging fulcrum of the cam ring 4 toward the second fluid pressure chamber A2. The reference port KK connecting the intermediate point M at the start end of the discharge ports 63 and 122 and the rotation center O of the drive shaft 2 has an inclination that gradually separates.

  As a result, the support surface N of the cam ring 4 is inclined reversely, and vibration can be suppressed in both the low rotation high discharge pressure state and the high rotation low discharge pressure state.

  (5) The cam ring 4 is further provided with a spring 201 that biases the cam ring 4 toward the first fluid pressure chamber A1. As a result, the discharge amount (cam ring 4 swing position) can be stabilized at the time of pump start when the pressure is not stable.

  (6) The cam ring 4 is controlled to swing by controlling the pressure only on the second fluid pressure chamber A2 side of the first fluid pressure chamber A1 and the second fluid pressure chamber A2. Accordingly, since the pressure in the second fluid pressure chamber A2 is controlled without controlling the pressure in the first fluid pressure chamber A1, pressure control is easier than that in which both the first and second fluid pressure chambers A2 are controlled. It becomes.

  (8) (12) The pump body 10 further includes an annular adapter ring 5 provided on the outer peripheral side of the cam ring 4, and a control pressure Pv for controlling the pressure in the second fluid pressure chamber A 2 is formed in the adapter ring 5. The through holes 52 are introduced.

  By providing the through hole 52 provided in the adapter ring 5 in the center of the adapter ring 5 in the axial direction, the outer peripheral surface of the adapter ring 5 becomes a sealing surface, and pressure leakage can be prevented.

  (9) In the variable displacement vane pump provided with the orifice 8 provided in the oil passage communicating with the discharge ports 63 and 122 and the control valve 7 into which the differential pressure across the orifice 8 is introduced, the control valve 7 The first fluid pressure chamber A1 is not controlled, and the second fluid pressure chamber A2 is controlled. Thereby, the flow rate control can be simplified by controlling only the second fluid pressure chamber A2.

  (10) The first and second seal members 50 and 40 are provided in a pair on the outer periphery of the cam ring 4. The outer periphery of the cam ring 4 is separated into the first and second fluid pressure chambers A 2 and controlled by the control valve 7. The control pressure Pv is introduced to the entire pressure receiving surface defined by the pair of first and second seal members 50 and 40 of the cam ring 4.

  Since the entire second fluid pressure chamber A2 is a pressure receiving surface, the pressure receiving area can be increased, and the control pressure Pv force can be reduced. Therefore, the amount of leakage from the second fluid pressure chamber A2 to the low pressure side (suction ports 62, 121) can be suppressed.

[Controlling the third fluid pressure chamber]
Example 2 will be described with reference to FIG. Since the basic configuration is the same as that of the first embodiment, only different points will be described. In Example 1, the pressure P2 of the second fluid pressure chamber A2 was controlled.

  On the other hand, in the second embodiment, the piston 200 is provided in place of the plug member 70, and a space defined by the inner periphery of the piston 200 and the lid member 202 is defined as a third fluid pressure chamber A3. A3 communicates with the control valve 7. This differs from the first embodiment in that the pressure P3 in the third fluid pressure chamber A3 is controlled.

  FIG. 4 is a radial sectional view of the vane pump 1 according to the second embodiment. The bottomed cup-shaped piston 200 is inserted into the piston insertion hole 114 ′ of the first housing 11 and the radial through hole 51 of the adapter ring 5 with the bottom 210 facing the negative y-axis direction. At the time of insertion, the outer periphery of the piston 200 and the piston insertion hole 114 ′ are provided so as to be slidable in the y-axis direction while maintaining liquid tightness.

  The piston insertion hole 114 ′ is liquid-tightly closed with the lid member 202, and the third fluid pressure chamber A 3 is separated by the inner periphery of the piston 200 and the lid member 202. The third fluid pressure chamber A3 is formed on the outer peripheral side of the discharge ports 63 and 122.

  A spring 201 is inserted into the inner periphery of the piston 200 so as to be extendable in the y-axis direction, and the positive side of the y-axis is locked by the lid member 202 to urge the piston 200 in the negative y-axis direction.

  As a result, the bottom portion 210 of the piston 200 passes through the radial through hole 51 of the adapter ring 5 and comes into contact with the cam ring 4, reaches the second fluid pressure chamber A2, and biases the cam ring 4 in the negative y-axis direction.

  Further, a connection passage 24 that connects the third fluid pressure chamber A3 and the control valve 7 is provided in the first housing 11 of the second embodiment. The connection passage 24 opens into a valve housing hole 115 that accommodates the control valve 7, and the control pressure Pv is introduced into the third fluid pressure chamber A3 as the pump is driven.

  As in the first embodiment, the control valve 7 is connected to the discharge ports 63 and 122 via the oil passages 21 and 22. An orifice 8 is provided on the oil passage 22, and a discharge pressure Pout that is an upstream pressure of the orifice 8 and a downstream pressure Pfb of the orifice 8 are introduced into the control valve 7. The control valve 7 is driven by the differential pressure between Pout and Pfb and the valve spring 7a to generate the control pressure Pv.

  As in the first embodiment, the support surface N that supports the cam ring 4 is inclined in the negative z-axis direction as it goes in the positive y-axis direction, and the control pressure Pv is higher than the suction pressure Pin. Therefore, by introducing the control pressure Pv into the third fluid pressure chamber A3, the cam ring 4 is prevented from falling to the second fluid pressure chamber A2 side (y-axis negative direction side).

[Effect of Example 2]
(13) In the variable displacement vane pump 1 including the orifice 8 provided in the oil passage 22 communicating with the discharge ports 63 and 122 and the control valve 7 into which the differential pressure across the orifice 8 is introduced, the control valve 7 is Of the plurality of chambers in the outer peripheral space of the cam ring 4, the pressure is controlled only in the third fluid pressure chamber A3 on the side where the discharge amount decreases due to the swing of the cam ring 4 and the control pressure Pv is introduced. did.

  Thereby, since the control valve 7 controls only the third fluid pressure chamber A3 into which the high control pressure Pv is introduced, the flow rate control can be simplified.

  (14) The seal member 50 has a first fluid pressure chamber A1 formed in the outer circumferential side space of the cam ring 4 on the side where the discharge amount increases by the swing of the cam ring 4, and the discharge amount decreases by the swing of the cam ring 4. The second fluid pressure chamber A2 and the third fluid pressure chamber formed on the side (y-axis positive direction side) are separated, and the control valve 7 controls the third fluid pressure chamber.

  Thereby, the y-axis positive direction side is divided into the second fluid pressure chamber A2 and the third fluid pressure chamber A3, the region of the third fluid pressure chamber into which the control pressure Pv is introduced is limited, and the flow becomes smaller. By adopting the configuration, the flow rate control of the pump can be made more efficient.

  (15) The control valve 7 is provided on the outer peripheral side of the third fluid pressure chamber A3. As a result, the control valve 7 for introducing the control pressure Pv into the third fluid pressure chamber A3 can be provided on the third fluid pressure chamber side A3, and the connection passage connecting the third fluid pressure chamber A3 and the control valve 7 24 can be simplified.

  (17) The piston 200 is further provided with a liquid-tight piston 200 that can move forward and backward with respect to the cam ring 4, and the third fluid pressure chamber A3 is formed inside the piston 200. Thereby, the leakage of the internal pressure of the third fluid pressure chamber A3 can be further suppressed.

  Example 3 will be described with reference to FIG. The basic configuration is the same as in the first and second embodiments. The third embodiment is different from the first and second embodiments in that the second fluid pressure chamber A2 is divided, the third fluid pressure chamber A3 is separated, and only the pressure P3 of the third fluid pressure chamber A3 is controlled.

[The third fluid pressure chamber is separated by the seal member]
FIG. 5 is a radial sectional view of the vane pump 1 according to the third embodiment. A third seal member 300 is provided between the cam ring 4 and the adapter ring 5 on the y-axis positive direction side of the second seal member 40, and separates the second fluid pressure chamber A2 to form the third fluid pressure chamber A3. Form. In Example 3, the z-axis positive direction side with respect to the third seal member 300 is defined as the second fluid pressure chamber A2, and the z-axis negative direction side is defined as the third fluid pressure chamber A3. In the third embodiment, the third seal member 300 is provided on the negative z-axis direction side of the plug member 70, but may be provided on the positive z-axis direction side (see Example 3-1).

  The third fluid pressure chamber A3 is connected to the control valve 7 via the oil passage 25, and the control pressure Pv is introduced. On the other hand, the second fluid pressure chamber A2 does not communicate with the suction and discharge sides and the control valve 7, and leak pressure flows. The suction pressure Pin is introduced into the first fluid pressure chamber A1 through the radial communication groove 64 as in the first embodiment.

  Therefore, the cam ring 4 is biased in the y-axis positive direction by the pump internal pressure, while the cam ring 4 is moved in the y-axis negative direction by the control pressure Pv introduced into the third fluid pressure chamber A3 provided on the y-axis positive direction side. It is energized to the side.

[Details of seal members]
The third seal member 300 has a swing fulcrum 310 and a protrusion 320 protruding from the swing fulcrum 310. The swing fulcrum 310 has a circular cross section, and is embedded in the recess 54 provided on the inner peripheral surface 53 of the adapter ring so as to be rotatable in the yz plane.

  The protrusion 320 is exposed from the adapter ring 5 and rotates in the third fluid pressure chamber A3 about the swing fulcrum 310. The clockwise rotation is counterclockwise by the locking portion 55. The rotation is locked by the holding portion 56.

  Here, in a state where the control pressure Pv is not introduced into the third fluid pressure chamber A3, the top portion 321 of the protruding portion 320 is provided to protrude to the inner diameter side from the adapter ring inner peripheral surface 53, and the third seal member 300 is provided. Is tilted in the negative y-axis direction. When the pump is driven and the discharge pressure starts to be introduced into the third fluid pressure chamber A3, the hydraulic oil flows from the third fluid pressure chamber A3 to the second fluid pressure chamber A2 side.

  When this flow hits the protruding portion 320, the third seal member 300 rises in the y-axis positive direction and the z-axis positive direction side, and the cam ring 4 is locked so that the third seal member 300 is in the third fluid pressure chamber A3. It maintains the control pressure Pv and exhibits sealing properties.

  Since the third seal member 300 has a structure that exerts a sealing property by pressure, it is possible to obtain a sealing force corresponding to the pressure. Therefore, it is possible to prevent the urging force from becoming too strong at a low pressure with little leakage, or the urging force from being insufficient at a high pressure with much leakage like a spring having a constant urging force.

  The protrusion 320 can always contact the outer periphery of the cam ring 4 regardless of the swinging position of the cam ring 4. Accordingly, the third seal member 300 receives the control pressure Pv from the oil passage 25 and rotates in the clockwise direction, and the protrusion 320 contacts the outer periphery of the cam ring 4 to separate the third fluid pressure chamber A3.

  A stopper portion 57 that protrudes toward the inner diameter side of the pump is provided on the positive side in the z-axis direction of the recess 54 in the adapter ring 5. In the adapter ring 5, the stopper portion 57 is formed to be thicker than other portions, and the strength around the recess 54 is improved.

[Eccentricity of cam ring and action of oil chamber]
In the variable displacement vane pump that constantly introduces the suction pressure into the second fluid pressure chamber A2 provided on the side where the pump volume decreases, the cam ring 4 is installed in order to constantly introduce the suction pressure into the second fluid pressure chamber A2. The force for biasing in the negative axis direction tends to be insufficient. In particular, when the support surface N of the adapter ring 5 is inclined toward the y-axis positive direction and the z-axis negative direction side as in the vane pump of the present application, the cam ring 4 falls to the second fluid pressure chamber A2 side unexpectedly. There is a high possibility that the pump discharge amount will decrease.

  Therefore, in the third embodiment, the third seal member 300 is provided on the y-axis positive direction side of the second seal member 40 to separate the third fluid pressure chamber A3, and the control pressure Pv is introduced to make the cam ring 4 negative in the y-axis negative direction. Energize in the direction. A force for urging the cam ring 4 in the negative y-axis direction is secured, and it is avoided that the cam ring 4 falls to the positive y-axis side and the pump discharge amount is reduced.

[Effect of Example 3]
(18) The third seal member 300 that separates the second fluid pressure chamber A2 and the third fluid pressure chamber A3 is urged against the cam ring 4 by the control pressure Pv introduced into the third fluid pressure chamber A3, It was decided to exhibit sealing properties.

  Since the third seal member 300 has a structure that exerts a sealing property by pressure, it is possible to obtain a sealing force corresponding to the pressure. Therefore, it is possible to prevent the urging force from becoming too strong at a low pressure with little leakage, or the urging force from being insufficient at a high pressure with many leakages like a spring having a constant urging force.

  (19) Also in Example 3, the support surface N has the inclined surface N that is gradually separated from the reference line KK connecting the intermediate point M and the rotation center O of the drive shaft 2. The support surface N of the cam ring 4 is inclined reversely, so that vibration can be suppressed in both the low rotation high discharge pressure state and the high rotation low discharge pressure state.

  (20) Among the plurality of first to third fluid pressure chambers A1 to A3 in the outer peripheral space of the cam ring 4, the first fluid pressure chamber A1 on the side where the discharge amount increases and the suction ports 62 and 121 are communicated. The communication groove 64 is further provided.

  As a result, the first fluid pressure chamber A1 is connected to the suction ports 62 and 121 with the cam ring 4 interposed therebetween, and the suction pressure Pin is introduced into the first fluid pressure chamber A1, thereby being discharged from the first fluid pressure chamber A1. Since the working oil is returned to the suction ports 62 and 121 side, the suction efficiency can be improved.

  Since the third fluid pressure chamber A3 is formed on the outer peripheral side of the discharge ports 63 and 122, the third fluid pressure chamber A3 into which the high control pressure Pv is introduced is provided on the outer peripheral side of the discharge ports 63 and 122. The pressure leakage from the third fluid pressure chamber A3 is suppressed, and the pressure does not leak to the suction ports 62 and 121 side. Further, the third fluid pressure chamber A3 is formed inside the piston 200, and the leakage is further reduced.

  (16) The third fluid pressure chamber A3 is formed on the outer peripheral side of the discharge ports 63 and 122. Thus, by providing the third fluid pressure chamber A3 into which the high control pressure Pv is introduced on the outer peripheral side of the discharge ports 63 and 122, pressure leakage from the third fluid pressure chamber A3 can be suppressed (suction). No pressure leaks to the ports 62 and 121 side).

The following is a modification of the third embodiment.
[Example 3-1]
FIG. 6 shows an example in which the third seal member 300 is provided on the positive side of the plug member 70 in the z-axis direction. Since it is provided at a position away from the cam ring swinging support surface N, the pressure receiving area can be reduced and leakage can be reduced. Further, since the third seal member 300 is provided near the valve, the passage becomes easy.

[Other embodiments]
The best mode for carrying out the present invention has been described based on each embodiment, but the specific configuration of the present invention is not limited to each embodiment and does not depart from the gist of the invention. Such design changes are included in the present invention.

It is an axial sectional view of a vane pump in Example 1 (control pressure introduction into the 2nd fluid pressure room). It is radial direction sectional drawing (at the time of the largest rocking | fluctuation) of the vane pump in Example 1. FIG. It is radial direction sectional drawing (at the time of the minimum rocking | fluctuation) of the vane pump in Example 1. FIG. It is radial direction sectional drawing of the vane pump in Example 2 (control pressure introduction | transduction to a 3rd fluid pressure chamber). It is radial direction sectional drawing of the vane pump in Example 3 (a 3rd fluid pressure chamber is separated by the 3rd seal member). It is radial direction sectional drawing of the vane pump in Example 3-1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vane pump 2 Drive shaft 3 Rotor 4 Cam ring 5 Adapter ring 6 Side plate 6 Pressure plate 7 Control valve 7a Valve spring 8 Orifice 10 Pump body 11,12 1st, 2nd housing 21,22 Oil path 24 Connection path 25 Oil path 31 Slot 32 Vane 33 Back pressure chamber 40 Pin 50 Seal member 41 Cam ring inner peripheral surface 51 Radial through hole 52 Through hole 53 Adapter ring inner peripheral surface 54 Recessed portion 55 Locking portion 56 Holding portion 57 Stopper portion 62, 121 Suction port 63, 122 Discharge port 64 Communication groove 70 Plug member 111 Bottom portion 112 Pump element accommodating portion 113 Oil passage 114 Plug member insertion hole 114 ′ Piston insertion hole 115 Valve housing hole 120 x-axis negative direction surface 200 Piston 201 Spring 202 Lid member 210 Bottom portion 300 Sea Member 310 swing fulcrum 320 protrusion 321 top A1~A3 first to third fluid pressure chamber B pump chamber

Claims (20)

A pump body;
A drive shaft supported by the pump body;
A rotor provided in the pump body and driven to rotate by the drive shaft;
Vanes accommodated in a slot provided in the circumferential direction of the rotor so as to freely appear and disappear;
A cam ring that is swingably provided in the pump body, and forms a plurality of pump chambers together with the rotor and the vane on the inner peripheral side;
A first member and a second member provided on both axial sides of the cam ring;
A suction port provided on at least one side of the first member or the second member and opening to a region where the volumes of the plurality of pump chambers increase, and discharge opening to a region where the volumes of the plurality of pump chambers decrease Port,
A first fluid pressure chamber provided on the outer peripheral side of the cam ring and provided in a direction in which the pump discharge amount increases in the outer peripheral side space of the cam ring, and a second fluid pressure chamber provided in a direction in which the pump discharge amount decreases. A sealing member that is separated into
And a control valve that controls only the hydraulic pressure of the second fluid pressure chamber. The variable displacement vane pump according to claim 1,
The variable displacement vane pump further comprising a communication passage for communicating the first fluid pressure chamber and the suction port. The variable displacement vane pump according to claim 2,
The variable passage vane pump, wherein the communication path is the first member or the second member and is formed on a surface facing the cam ring. The variable displacement vane pump according to claim 2,
The support surface for supporting the cam ring has an end point of the suction port, an intermediate point of the start end of the discharge port, and a rotation center of the drive shaft from the swinging fulcrum of the cam ring toward the second fluid pressure chamber side. A variable displacement vane pump characterized by having an inclination that gradually separates from a connected reference line. The variable displacement vane pump according to claim 2,
The variable capacity vane pump further comprising urging means for urging the cam ring toward the first fluid pressure chamber. A pump body;
A drive shaft supported by the pump body;
A rotor provided in the pump body and driven to rotate by the drive shaft;
Vanes accommodated in a slot provided in the circumferential direction of the rotor so as to freely appear and disappear;
A cam ring that is swingably provided in the pump body, and forms a plurality of pump chambers together with the rotor and the vane on the inner peripheral side;
A first member and a second member provided on both axial sides of the cam ring;
A suction port provided on at least one side of the first member or the second member and opening to a region where the volumes of the plurality of pump chambers increase, and discharge opening to a region where the volumes of the plurality of pump chambers decrease Port,
A first fluid pressure chamber provided on the outer peripheral side of the cam ring and provided in a direction in which the pump discharge amount increases in the outer peripheral side space of the cam ring, and a second fluid pressure chamber provided in a direction in which the pump discharge amount decreases. And a sealing member separated from each other,
The cam ring is swing-controlled by pressure-controlling only the second fluid pressure chamber side of the first fluid pressure chamber and the second fluid pressure chamber. . The variable displacement vane pump according to claim 6,
The support surface that supports the cam ring is a reference line that connects the intermediate point of the start end of the suction port and the rotation center of the drive shaft from the swinging fulcrum of the cam ring toward the second fluid pressure chamber side. A variable displacement vane pump characterized by having a slope that gradually separates. The variable displacement vane pump according to claim 6,
The pump body further includes an annular adapter ring provided on the outer peripheral side of the cam ring,
The variable pressure vane pump, wherein the control pressure for controlling the pressure of the second fluid pressure chamber is introduced through a through hole formed in the adapter ring. A pump body;
A drive shaft supported by the pump body;
A rotor provided in the pump body and driven to rotate by the drive shaft;
Vanes accommodated in a slot provided in the circumferential direction of the rotor so as to freely appear and disappear;
A cam ring that is swingably provided in the pump body, and forms a plurality of pump chambers together with the rotor and the vane on the inner peripheral side;
A first member and a second member provided on both axial sides of the cam ring;
A suction port provided on at least one side of the first member or the second member and opening to a region where the volumes of the plurality of pump chambers increase, and discharge opening to a region where the volumes of the plurality of pump chambers decrease Port,
A first fluid pressure chamber provided on the outer peripheral side of the cam ring and provided in a direction in which the pump discharge amount increases in the outer peripheral side space of the cam ring, and a second fluid pressure chamber provided in a direction in which the pump discharge amount decreases. A sealing member that is separated into
An orifice provided in an oil passage communicating with the discharge port;
A variable displacement vane pump comprising: a control valve into which a differential pressure across the orifice is introduced;
The variable displacement vane pump, wherein the control valve controls the second fluid pressure chamber without controlling the first fluid pressure chamber. The variable displacement vane pump according to claim 9,
The seal member is provided in a pair on the outer periphery of the cam ring, and the outer periphery of the cam ring is divided into the first and second fluid pressure chambers,
The variable pressure vane pump, wherein the control pressure controlled by the control valve is introduced to the entire pressure receiving surface separated by the pair of seal members of the cam ring. The variable displacement vane pump according to claim 9,
The support surface that supports the cam ring has an end point of the suction port and an intermediate point of the start end of the discharge port from the swing fulcrum of the cam ring toward the second fluid pressure chamber side, and the rotation center of the drive shaft. A variable displacement vane pump characterized by having an inclination that gradually separates from a connected reference line. The variable displacement vane pump according to claim 9,
The pump body further includes an annular adapter ring provided on the outer peripheral side of the cam ring,
The variable pressure vane pump, wherein the control pressure for controlling the pressure of the second fluid pressure chamber is introduced through a through hole formed in the adapter ring. A pump body;
A drive shaft supported by the pump body;
A rotor provided in the pump body and driven to rotate by the drive shaft;
Vanes accommodated in a slot provided in the circumferential direction of the rotor so as to freely appear and disappear;
A cam ring that is swingably provided in the pump body, and forms a plurality of pump chambers together with the rotor and the vane on the inner peripheral side;
A first member and a second member provided on both axial sides of the cam ring;
A suction port provided on at least one side of the first member or the second member and opening to a region where the volumes of the plurality of pump chambers increase, and discharge opening to a region where the volumes of the plurality of pump chambers decrease Port,
A first fluid pressure chamber provided on the outer peripheral side of the cam ring and provided in a direction in which the pump discharge amount increases in the outer peripheral side space of the cam ring, and a second fluid pressure chamber provided in a direction in which the pump discharge amount decreases. A sealing member that is separated into
An orifice provided in an oil passage communicating with the discharge port;
A variable displacement vane pump comprising: a control valve into which a differential pressure across the orifice is introduced;
The control valve controls the pressure of only a chamber on the side where the discharge amount is reduced due to the swing of the cam ring among the plurality of chambers on the outer peripheral side space of the cam ring and into which the discharge pressure is introduced. Variable displacement vane pump. The variable displacement vane pump according to claim 13,
The seal member is formed on the side where the discharge amount is reduced by the swing of the cam ring and the first fluid pressure chamber formed on the outer peripheral side space of the cam ring on the side where the discharge amount is increased by the swing of the cam ring. A second fluid pressure chamber and a third fluid pressure chamber;
The variable displacement vane pump, wherein the control valve controls the third fluid pressure chamber. The variable displacement vane pump according to claim 14,
The variable displacement vane pump, wherein the control valve is provided on an outer peripheral side of the third fluid pressure chamber. The variable displacement vane pump according to claim 14,
The variable displacement vane pump, wherein the third fluid pressure chamber is formed on an outer peripheral side of the discharge port. The variable displacement vane pump according to claim 14,
It further includes a plug member that is movable forward and backward with respect to the cam ring and provided in a liquid-tight manner,
The variable displacement vane pump, wherein the third fluid pressure chamber is formed in the plug member. The variable displacement vane pump according to claim 14,
The seal member that separates the second fluid pressure chamber and the third fluid pressure chamber is urged by the cam ring by the pressure introduced into the third fluid pressure chamber, and exhibits a sealing property. Variable displacement vane pump. The variable displacement vane pump according to claim 13,
The support surface that supports the cam ring has an end point of the suction port, an intermediate point of the start end of the discharge port, and a rotation center of the drive shaft from the swinging fulcrum of the cam ring toward the side where the discharge amount decreases. A variable displacement vane pump characterized by having an inclination that gradually separates from a connected reference line. The variable displacement vane pump according to claim 13,
The variable capacity vane pump, further comprising: a communication path that communicates the suction port with a chamber that increases the discharge amount among the plurality of chambers in the outer peripheral space of the cam ring.

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