JP5998044B2 - Variable pump - Google Patents

Description

  The present invention relates to a variable pump that supplies pressurized working fluid to a fluid pressure device.

  A variable pump is used as a hydraulic supply source for hydraulic equipment mounted on a vehicle, for example, a power steering device or a continuously variable transmission.

  In Patent Document 1, a variable displacement vane pump pump having a variable pump discharge capacity, an electromagnetic throttle valve interposed in the pump discharge passage, and pump discharge according to the differential pressure between the upstream pressure and the downstream pressure of the electromagnetic throttle valve. A variable pump comprising a control valve for controlling the capacity is disclosed.

  By adjusting the opening of the electromagnetic throttle valve, the flow rate of the hydraulic oil sent from the pump discharge passage to the hydraulic equipment is adjusted.

  The control valve is guided by the differential pressure between the upstream pressure and the downstream pressure of the electromagnetic throttle valve generated in the pump discharge passage as the signal pressure, and adjusts the drive pressure for moving the cam ring in accordance with the differential pressure.

  In the variable displacement vane pump, the pump ring displacement is changed by the cam ring swinging around the support pin as a fulcrum by the driving pressure guided through the control valve.

JP 2001-159395 A

  In the variable pump disclosed in Patent Document 1, the control valve is housed inside the pump body of the variable displacement vane pump, while the electromagnetic throttle valve is provided outside the pump body. A pump discharge passage connecting the valves is provided by piping.

  The upstream pressure (signal pressure) of the electromagnetic throttle valve guided to the control valve is a value that does not include the pressure loss of the pipe because the pump discharge pressure is guided to the control valve through the pressure guiding passage provided inside the pump body. On the other hand, since the downstream pressure (signal pressure) of the electromagnetic throttle valve led to the control valve is led through the pipe constituting the pump discharge passage, it becomes a value including the pressure loss of the pipe.

  As described above, since the downstream pressure (signal pressure) of the electromagnetic throttle valve guided to the control valve is affected by the pressure loss of the pipe, the pressure loss of the pipe constituting the pump discharge passage increases or decreases according to the pump discharge flow rate. Therefore, there is a problem that it is difficult to control the pump discharge flow rate to the target value.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a variable pump that controls the pump discharge flow rate while suppressing the influence of pressure loss in the pump discharge passage.

  The present invention is a variable pump that supplies a pressurized working fluid to a fluid pressure device, and is provided inside a pump body, a pump element whose discharge capacity is adjusted by a driving pressure, and a pump element according to a signal pressure A control valve for controlling the drive pressure led to the pump, a pump discharge passage for guiding the working fluid discharged from the pump element to the fluid pressure device, and a variable throttle provided inside the valve body and interposed in the pump discharge passage. An electromagnetic throttle valve that adjusts the opening according to the current value, a first pressure guiding passage that leads the upstream pressure of the variable throttle in the electromagnetic throttle valve as a signal pressure to the control valve, and a downstream pressure of the variable throttle in the electromagnetic throttle valve And a second pressure guiding passage that guides the valve as a signal pressure.

  In the present invention, since the first pressure guiding passage and the second pressure guiding passage are connected to the downstream side of the passage portion connecting the pump body and the valve body in the pump discharge passage, the electromagnetic throttle valve guided as a signal pressure to the control valve Both the upstream pressure and the downstream pressure have values including pressure loss in the passage portion of the pump discharge passage. For this reason, the differential pressure of the signal pressure guided to the control valve does not change due to the pressure loss in the passage part of the pump discharge passage, and the control valve targets the pump discharge flow rate while suppressing the influence of the pressure loss in the passage part of the pump discharge passage. Can be adjusted to the value.

It is a block diagram of the variable pump which concerns on embodiment of this invention. It is a figure which shows the relationship between the rotational speed of the rotor which concerns on embodiment of this invention, and a pump discharge flow rate.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  First, a variable pump 100 according to an embodiment of the present invention will be described with reference to FIG.

  The variable pump 100 is used, for example, as a hydraulic (fluid pressure) supply source that supplies hydraulic oil to a hydraulic device (fluid pressure device) 60 such as a power steering device or a continuously variable transmission mounted on a vehicle.

  The variable pump 100 includes a variable displacement vane pump 10 (hereinafter simply referred to as “vane pump 10”). Hereinafter, a configuration in which the hydraulic oil pressurized by the vane pump 10 is supplied to the hydraulic device 60 will be described.

  The vane pump 10 uses a working oil (oil) as a working fluid, but a working fluid such as a water-soluble alternative liquid may be used instead of the working oil.

  The vane pump 10 includes, as a pump element 15 that pressurizes and discharges hydraulic oil, a rotor 2 that is rotated by a drive shaft 1, a plurality of vanes 3 that can be reciprocated in a radial direction with respect to the rotor 2, And a cam ring 4 for accommodating the vane 3. As the rotor 2 rotates, the tip of the vane 3 slides on the cam surface 4A formed on the inner periphery of the cam ring 4. A pump chamber 7 partitioned by each vane 3 is defined between the rotor 2 and the cam ring 4.

  Power of an engine (not shown) is transmitted to the drive shaft 1. The rotor 2 connected to the drive shaft 1 rotates counterclockwise as indicated by an arrow in FIG.

  The drive shaft 1 is rotatably supported by a pump body 18 and a pump cover (not shown) via a bearing (not shown). The pump body 18 is formed with an accommodation space for accommodating the rotor 2 and the cam ring 4. A side plate (not shown) that abuts against one side of the rotor 2 and the cam ring 4 is disposed on the bottom surface of the housing space. The opening of the accommodation space is sealed by a pump cover that contacts the other side of the rotor 2 and the cam ring 4. The pump cover and the side plate are disposed in a state where both sides of the rotor 2 and the cam ring 4 are sandwiched.

  The side plate has a suction port (not shown) that guides hydraulic oil into the pump chamber 7 and a discharge port (not shown) that takes the hydraulic oil from the pump chamber 7 and leads it to the hydraulic device 60 outside the vane pump 10. It is formed. The suction port communicates with the tank 9 via the suction passage 17. The discharge port communicates with the hydraulic device 60 through the pump discharge passage 50.

  During the operation of the vane pump 10, in the suction region of the cam ring 4, the vane 3 slidably contacting the cam surface 4 </ b> A protrudes from the rotor 2 and the pump chamber 7 is expanded. Sucked into. In the discharge region of the cam ring 4, the vane 3 slidably contacting the cam surface 4 </ b> A is pushed into the rotor 2, the pump chamber 7 contracts, and hydraulic fluid pressurized in the pump chamber 7 is hydraulically supplied from the discharge port through the pump discharge passage 50. Supplied to the device 60.

  Hereinafter, the structure which changes the discharge capacity | capacitance (displacement volume) of the pump element 15 is demonstrated.

  The pump element 15 includes an annular adapter ring 11 that surrounds the cam ring 4. A support pin 13 is interposed between the adapter ring 11 and the cam ring 4. The cam ring 4 is supported by the support pin 13, and the cam ring 4 swings around the support pin 13 inside the adapter ring 11 and is eccentric with respect to the center of the rotor 2.

  In the groove 11 </ b> A of the adapter ring 11, a seal material 14 is interposed in which the outer peripheral surface of the cam ring 4 is slidably contacted when the cam ring 4 is swung. Between the outer peripheral surface of the cam ring 4 and the inner peripheral surface of the adapter ring 11, a first fluid pressure chamber 31 and a second fluid pressure chamber 32 are partitioned by the support pins 13 and the sealing material 14. The cam ring 4 oscillates with respect to the support pin 13 due to the driving pressure guided to the first fluid pressure chamber 31 and the second fluid pressure chamber 32 and the pressure balance of the pump chamber 7.

  When the cam ring 4 swings in the right direction in FIG. 1, the amount of eccentricity of the cam ring 4 with respect to the rotor 2 decreases, and the discharge capacity of the pump chamber 7 decreases. On the other hand, when the cam ring 4 swings leftward in FIG. 1, the amount of eccentricity of the cam ring 4 with respect to the rotor 2 increases, and the discharge capacity of the pump chamber 7 increases.

  The variable pump 100 includes a control valve 21 that controls the driving pressure guided to the first fluid pressure chamber 31 and the second fluid pressure chamber 32.

  The control valve 21 includes a spool 22 slidably inserted into the valve accommodation hole 29, a first spool chamber 24 defined between one end of the spool 22 and the valve accommodation hole 29, and the other end of the spool 22. And a valve housing hole 29, and a return spring 26 accommodated in the second spool chamber 25. The return spring 26 urges the spool 22 in the direction of expanding the volume of the second spool chamber 25.

  The spool 22 is a stepped columnar member, and the first land portion 22A and the second land portion 22B slide along the inner peripheral surface of the valve accommodating hole 29, and the first land portion 22A and the second land. And an annular groove 22C formed between the portion 22B.

  The control valve 21 is configured to operate by a differential pressure across the electromagnetic throttle valve 41 interposed in the pump discharge passage 50. The hydraulic oil pressure P <b> 1 generated upstream of the electromagnetic throttle valve 41 (hereinafter simply referred to as “upstream pressure P <b> 1”) is guided to the first spool chamber 24 of the control valve 21 through the first pressure guiding passage 37. The hydraulic oil pressure P2 (hereinafter simply referred to as “downstream pressure P2”) generated downstream of the electromagnetic throttle valve 41 is guided to the second spool chamber 25 of the control valve 21 through the second pressure guide passage 38.

  The control valve 21 communicates with the first driving pressure passage 33 communicating with the first fluid pressure chamber 31, the second driving pressure passage 34 communicating with the second fluid pressure chamber 32, and the suction passage 17 with the annular groove 22C. A drain passage 35 is connected.

  The spool 22 of the control valve 21 has a load caused by the differential pressure P1-P2 between the upstream pressure P1 and the downstream pressure P2 guided as a signal pressure to the first spool chamber 24 and the second spool chamber 25, and an urging force of the return spring 26. Move to the balance position and stop. Depending on the stop position of the spool 22, the first drive pressure passage 33 and the second drive pressure passage 34 are opened and closed by the first land portion 22A and the second land portion 22B, respectively, and the first fluid pressure chamber 31 and the second fluid pressure chamber 32 are opened. The hydraulic oil is supplied and discharged.

  Hereinafter, the operation of the control valve 21 that controls the driving pressure guided to the first fluid pressure chamber 31 and the second fluid pressure chamber 32 will be described.

  When the rotational speed of the rotor 2 is low, such as when the pump is started, the front-rear differential pressure P1-P2 of the electromagnetic throttle valve 41 is small. Therefore, the total load of the load due to the pressure of the second spool chamber 25 and the biasing force of the return spring 26 becomes larger than the load due to the pressure of the first spool chamber 24, and the spool 22 moves due to the biasing force of the return spring 26, The tip of the spool 22 comes into contact with the bottom of the valve housing hole 29.

  In this case, the first fluid pressure chamber 31 is blocked from communicating with the first pressure guiding passage 37 by the first land portion 22A of the spool 22, and via the communication passage 22D formed in the first land portion 22A. It communicates with the drain passage 35. The second fluid pressure chamber 32 is blocked from communicating with the drain passage 35 by the second land portion 22 </ b> B of the spool 22. The hydraulic fluid in the first fluid pressure chamber 31 is discharged to the drain passage 35 through the communication passage 22D and the annular groove 22C, and the hydraulic pressure in the pump discharge passage 50 is guided to the second fluid pressure chamber 32 through the throttle passage 36. Therefore, the cam ring 4 comes into contact with the bulging portion 11B of the inner peripheral surface of the adapter ring 11 due to the pressure of the hydraulic oil in the second fluid pressure chamber 32, and the eccentric amount with respect to the rotor 2 is maximized. Retained.

  When the eccentric amount of the cam ring 4 with respect to the rotor 2 is maximized, the vane pump 10 discharges the hydraulic oil with the maximum discharge capacity, and the flow rate Q of the hydraulic oil discharged from the vane pump 10 is the rotational speed N of the rotor 2. (See the characteristic between A and D in FIG. 2). Thereby, even when the rotational speed N of the rotor 2 is low, the hydraulic oil 60 can be supplied with a sufficient amount of hydraulic fluid Q.

  As the rotational speed N of the rotor 2 increases and the front-rear differential pressure P1-P2 of the electromagnetic throttle valve 41 increases, the load due to the pressure in the first spool chamber 24 and the return spring due to the pressure in the second spool chamber 25 When the total load with the urging force of 26 increases, the spool 22 moves to the right in FIG. 1 against the urging force of the return spring 26.

  In this case, the first fluid pressure chamber 31 communicates with the pump discharge passage 50 via the first drive pressure passage 33, the first spool chamber 24, and the first pressure guide passage 37. The second fluid pressure chamber 32 communicates with the drain passage 35 via the second drive pressure passage 34 and the annular groove 22C. The communication between the second drive pressure passage 34 and the annular groove 22 </ b> C is performed through a notch 22 </ b> E formed in the second land portion 22 </ b> B of the spool 22, and a drain passage for the second fluid pressure chamber 32 according to the amount of movement of the spool 22. The opening area of 35 increases or decreases.

  When the first fluid pressure chamber 31 communicates with the pump discharge passage 50 and the second fluid pressure chamber 32 communicates with the drain passage 35 as described above, the hydraulic fluid in the pump discharge passage 50 is supplied to the first fluid pressure chamber 31. Then, the hydraulic oil in the second fluid pressure chamber 32 is discharged to the drain passage 35. As a result, the cam ring 4 moves in the direction in which the amount of eccentricity with respect to the rotor 2 decreases (rightward in FIG. 1) in accordance with the pressure difference between the first fluid pressure chamber 31 and the second fluid pressure chamber 32. As the amount of eccentricity of the cam ring 4 with respect to the rotor 2 becomes smaller, the outer peripheral surface of the cam ring 4 comes into contact with the bulging portion 11C of the inner peripheral surface of the adapter ring 11, and the movement of the cam ring 4 is restricted. As a result, the amount of eccentricity of the cam ring 4 with respect to the rotor 2 is minimized, and the pump chamber 7 has the minimum discharge capacity.

  In this way, the control valve 21 is operated according to the differential pressure P1-P2 across the electromagnetic throttle valve 41 in the pump discharge passage 50 and the cam ring 4 moves, so that the vane pump 10 can be operated even when the rotational speed N of the rotor 2 increases. The discharge flow rate is adjusted to be substantially constant (see the characteristic between BF and DE in FIG. 2). Thereby, the pressure of the hydraulic oil supplied with respect to the hydraulic equipment 60 at the time of driving | running | working of a vehicle is adjusted moderately.

  The variable pump 100 includes a discharge flow rate adjustment system that adjusts the pump discharge flow rate Q of hydraulic oil based on a flow rate command signal transmitted from a controller (not shown) on the vehicle side. Hereinafter, the configuration of the discharge flow rate adjustment system will be described.

  In the middle of the pump discharge passage 50, the electromagnetic throttle valve 41 described above is interposed, and the pump discharge flow rate Q of the hydraulic oil supplied to the hydraulic equipment 60 through the pump discharge passage 50 is adjusted by the opening degree of the electromagnetic throttle valve 41. The

  The electromagnetic throttle valve 41 is accommodated in the valve body 39. The valve body 39 is formed separately from the pump body 18 that houses the pump element 15 and the control valve 21. As a result, the space for interposing the electromagnetic throttle valve 41 and the control valve 21 is divided into two locations, so that the outer shape of the vane pump 10 is larger than the configuration in which both the electromagnetic throttle valve 41 and the control valve 21 are interposed in the valve body 39. Can be reduced, and the degree of freedom of arrangement of the pump body 18 and the valve body 39 is ensured.

  The pump discharge passage 50 includes an in-pump pump discharge passage 51 provided in the pump body 18, a pipe 52 connecting the pump body 18 and the valve body 39, and an in-valve pump discharge passage 53 provided in the valve body 39. And a pipe 54 connecting the valve body 39 and the hydraulic device 60.

  After the hydraulic oil pressurized in the pump chamber 7 is discharged from the discharge port, the hydraulic oil flows in order through the pump discharge passage 51 in the pump, the pipe 52, the pump discharge passage 53 in the valve, and the pipe 54, and is supplied to the hydraulic equipment 60. Is done.

  The in-valve pump discharge passage 53 is provided with two branch pump discharge passages 53A and 53B that branch in parallel with each other. A fixed throttle 40 is interposed in the branch pump discharge passage 53A. On the other hand, an electromagnetic throttle valve 41 is interposed in the branch pump discharge passage 53B. That is, the fixed throttle 40 and the electromagnetic throttle valve 41 are interposed in parallel in the in-valve pump discharge passage 53.

  The electromagnetic throttle valve 41 includes a valve body 44 that is slidably inserted into the valve housing hole 43, a seat portion 45 that defines the variable throttle 42 against the valve body 44, and the valve body 44 from the seat portion 45. A spring 46 that urges the valve in the opening direction is provided, and a solenoid 47 that drives the valve body 44 in the closing direction to approach the seat portion 45 against the spring 46.

  The valve body 44 is a stepped cylindrical member (spool), and includes a first land portion 44A and a second land portion 44B that slide along the inner peripheral surface of the valve accommodation hole 43, and a first land portion 44A. And an annular groove 44C formed between the second land portion 44B.

  In the valve accommodation hole 43, a back pressure chamber 57 is defined behind the first land portion 44A, and a spring accommodation chamber 56 in which the spring 46 is accommodated behind the second land portion 44B. The back pressure chamber 57 and the spring accommodating chamber 56 are each communicated with the tank 9 through the drain passage 58.

  A first port 48 and a second port 49 are opened in the valve accommodating hole 43 of the electromagnetic throttle valve 41 with the variable throttle 42 (seat portion 45) interposed therebetween. The branch pump discharge passage 53 </ b> B includes a first port 48, a valve accommodation hole 43, and a second port 49.

  The electromagnetic throttle valve 41 is a proportional flow rate control valve that opens when not energized. In the solenoid 47, the current value flowing through the coil is controlled by the controller 70. In the electromagnetic throttle valve 41, the valve body 44 is moved with a stroke corresponding to the current value by the magnetic field generated in the coil of the solenoid 47, the opening degree (opening area) of the variable throttle 42 increases and decreases, and the variable throttle 42 flows the hydraulic oil. The flow path resistance applied to is adjusted.

  The electromagnetic throttle valve 41 may be configured to open and close the variable throttle 42 by interrupting (ON, OFF) the excitation current flowing through the coil.

  FIG. 2 is a characteristic diagram showing the relationship between the rotational speed N of the rotor 2 and the flow rate Q of hydraulic oil discharged from the vane pump 10.

  In the state where the electromagnetic throttle valve 41 is fully opened (the maximum opening state of the variable throttle 42), the maximum flow rate characteristic of A-D-E in FIG. 2 is obtained.

  2, as shown in FIG. 1, the cam ring 4 is held at a position where the eccentricity with respect to the rotor 2 is maximized, and the flow rate Q of the hydraulic oil discharged from the vane pump 10 is the rotational speed of the rotor 2. It is approximately proportional to N.

  2, as described above, even if the rotational speed N of the rotor 2 increases, the control valve 21 operates according to the differential pressure P1-P2 across the electromagnetic throttle valve 41 in the fully open state. As a result, the cam ring 4 moves in a direction in which the amount of eccentricity with respect to the rotor 2 decreases, and the pump discharge flow rate Q is adjusted to be substantially constant.

  On the other hand, when the electromagnetic throttle valve 41 is fully closed (the variable throttle 42 is closed), the minimum flow rate characteristic A-B-F in FIG. 2 is obtained. This minimum flow rate characteristic is set by the opening area of the fixed throttle 40 which is an orifice.

  The flow rate Q of the hydraulic oil flowing through the pump discharge passage 50 is adjusted by the total value of the flow path resistance that the fixed throttle 40 and the variable throttle 42 impart to the hydraulic oil flow. The controller 70 controls the opening degree of the variable throttle 42 so that the pump discharge flow rate Q is adjusted within the range of the maximum flow rate characteristic of A-D-E and the minimum flow rate characteristic of A-B-F.

  Hereinafter, a configuration in which the upstream pressure P1 and the downstream pressure P2 are extracted as the signal pressure of the control valve 21 in the electromagnetic throttle valve 41 will be described.

  When the variable pump 100 is operated, part of the hydraulic oil flowing through the pump discharge passage 50 is diverted to the branch pump discharge passage 53B, and the rest is diverted to the branch pump discharge passage 53A. In the branch pump discharge passage 53B, after the hydraulic fluid flows into the valve accommodating hole 43 from the first port 48, it is guided to the variable throttle 42 as indicated by an arrow in FIG. It flows to 49. On the other hand, hydraulic oil passes through the fixed throttle 40 in the branch pump discharge passage 53A. At this time, a pressure loss caused by the resistance applied by the variable throttle 42 and the fixed throttle 40 occurs in the flow of hydraulic oil, and the downstream pressure generated downstream of the upstream pressure P1 generated upstream of the variable throttle 42 and the fixed throttle 40. The pressure P2 decreases.

  A first pressure guiding passage 37 is connected to the first port 48. The first port 48 communicates with the upstream side of the fixed throttle 40 of the branch pump discharge passage 53 </ b> A, and opens to the upstream side of the variable throttle 42 at the valve accommodation hole 43. As a result, the upstream pressure P1 generated upstream of the fixed throttle 40 and the variable throttle 42 is guided from the first port 48 to the first spool chamber 24 of the control valve 21 through the first pressure guide passage 37.

  A second pressure guide passage 38 is connected to the second port 49. The second port 49 communicates with the downstream side of the fixed throttle 40 of the branch pump discharge passage 53 </ b> A and opens downstream of the variable throttle 42 through the valve accommodating hole 43. As a result, the downstream pressure P2 generated downstream of the fixed throttle 40 and the variable throttle 42 is guided from the second port 49 to the second spool chamber 25 of the control valve 21 through the second pressure guide passage 38.

  In this way, the first pressure guiding passage 37 and the second pressure guiding passage 38 are connected to the first port 48 and the second port 49 opened in the vicinity of the variable throttle 42 in the branch pump discharge passage 53B, respectively. The differential pressure P1-P2 generated by the resistance of the valve 42 and the fixed throttle 40 is guided to the control valve 21. Can be adjusted.

  According to the above embodiment, the following effects are obtained.

  [1] A pump element 15 provided inside the pump body 18 and whose discharge capacity is adjusted by the driving pressure, a control valve 21 for controlling the driving pressure guided to the pump element 15 according to the signal pressure, and the pump element 15 The opening of a pump discharge passage 50 that guides the working fluid discharged from the fluid pressure device 60 and the valve body 39 inside the pump discharge passage 50 is adjusted according to the current value. The electromagnetic throttle valve 41, the first pressure guiding passage 37 for guiding the upstream pressure P1 of the variable throttle 42 in the electromagnetic throttle valve 41 to the control valve 21 as a signal pressure, and the downstream pressure P2 of the variable throttle 42 in the electromagnetic throttle valve 41. And a second pressure guiding passage 38 that guides the valve 21 as a signal pressure.

  Based on the above configuration, the first pressure guiding passage 37 and the second pressure guiding passage 38 are independent from the passage portion (pipe 52) connecting the pump body 18 and the valve body 39 in the pump discharge passage 50. Both the upstream pressure P1 and the downstream pressure P2 of the electromagnetic throttle valve 41 guided as the signal pressure are not affected by the pressure loss of the passage portion (pipe 52) of the pump discharge passage 50. Therefore, the control valve 21 can adjust the pump discharge flow rate Q to the target value while suppressing the influence of the pressure loss in the passage portion of the pump discharge passage 50.

  [2] A part of the pump discharge passage 50 is provided, and a pipe 52 that connects the pump body 18 and the valve body 39 is provided. The first pressure guide path 37 and the second pressure guide path 38 are formed from the pipe 52 of the pump discharge path 50. It was set as the structure connected downstream.

  Based on the above configuration, since the first pressure guiding passage 37 and the second pressure guiding passage 38 are connected to the downstream side of the pipe 52, the upstream pressure P1 and the downstream pressure of the electromagnetic throttle valve 41 guided as signal pressure to the control valve 21. P2 is a value including the pressure loss of the pipe 52. For this reason, the differential pressure P1-P2 of the signal pressure led to the control valve 21 due to the pressure loss of the pipe 52 does not change, and the control valve 21 sets the pump discharge flow rate Q to the target value while suppressing the influence of the pressure loss of the pipe 52. Can be adjusted.

  [3] The electromagnetic throttle valve 41 has a valve body 44 that adjusts the opening degree of the variable throttle 42 by moving the valve accommodating hole 43 by electromagnetic force, and a first opening that opens in the valve accommodating hole 43 on the upstream side of the variable throttle 42. One port 48 and a second port 49 that opens to the valve accommodating hole 43 on the downstream side of the variable throttle 42, the first pressure guiding passage 37 is connected to the first port 48, and the second port 49 is connected to the second port 49. The two pressure guiding passages 38 are connected.

  Based on the above configuration, the upstream pressure P1 and the downstream pressure P2 generated in the vicinity of the variable throttle 42 are taken into the first pressure guiding passage 37 and the second pressure guiding passage 38 via the first port 48 and the second port 49, respectively. Therefore, the control valve 21 can adjust the pump discharge flow rate Q to the target value without being affected by the pressure loss in the passage portion other than the variable throttle 42 in the pump discharge passage 50.

  [4] The pump element 15 is defined between the adjacent vanes 3 as the tip of the vane 3 slides on the cam ring 4 in accordance with the rotation of the rotor 2 in which the plurality of vanes 3 are reciprocally movable. The working fluid is discharged from the pump chamber 7, and the cam ring 4 is moved by the driving pressure guided from the control valve 21.

  Based on the above configuration, the cam ring is moved by the driving pressure guided from the control valve 21 to adjust the pump discharge capacity, and the control valve 21 can adjust the pump discharge flow rate Q to the target value.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  For example, in the pump element 15, the suction pressure of hydraulic oil sucked into the pump chamber 7 is always guided to the first fluid pressure chamber 31, and the fluid pressure that the control valve 21 is guided from the pump chamber 7 to the second fluid pressure chamber 32 is set. The direction in which the discharge capacity of the cam ring 4 decreases due to the pressure of the pump chamber 7 acting on the cam surface 4A during the operation in which the fluid pressure guided to the second fluid pressure chamber 32 through the control valve 21 is lowered (in FIG. 1). While swinging in the right direction), the cam ring 4 swings in the direction in which the discharge capacity increases (leftward in FIG. 1) when the fluid pressure led to the second fluid pressure chamber 32 through the control valve 21 increases. It is good also as composition to do.

  Further, the valve body 39 is not limited to be provided outside the pump body 18, and the valve body 39 may be provided inside the pump body 18.

  The variable displacement vane pump of the present invention can be used for a hydraulic pressure supply source such as a power steering device or a continuously variable transmission mounted on a vehicle, and can also be used for a fluid pressure supply source of another machine or facility.

2 rotor 3 vane 4 cam ring 7 pump chamber 15 pump element 18 pump body 21 control valve 37 first pressure guide passage 38 second pressure guide passage 39 valve body 41 electromagnetic throttle valve 42 variable throttle 43 valve housing hole 44 valve body 48 first Port 49 Second port 50 Pump discharge passage 52 Piping 60 Hydraulic equipment (hydraulic pressure equipment)
100 variable pump

Claims (4)

A variable pump for supplying pressurized working fluid to a fluid pressure device,
A pump element provided inside the pump body, the discharge capacity of which is adjusted by the driving pressure;
A control valve for controlling a driving pressure guided to the pump element according to a signal pressure;
A pump discharge passage for guiding the working fluid discharged from the pump element to the fluid pressure device;
An electromagnetic throttle valve that is provided inside the valve body and adjusts the opening of a variable throttle interposed in the pump discharge passage according to a current value;
A first pressure guiding passage for guiding an upstream pressure of the variable throttle in the electromagnetic throttle valve as a signal pressure to the control valve;
A variable pump comprising: a second pressure guiding passage for guiding a downstream pressure of the variable throttle in the electromagnetic throttle valve as a signal pressure to the control valve. Constituting a part of the pump discharge passage, comprising a pipe connecting the pump body and the valve body;
The variable pump according to claim 1, wherein the first pressure guiding passage and the second pressure guiding passage are connected to the downstream side of the pipe of the pump discharge passage. A valve body that moves the valve housing hole by electromagnetic force to adjust the opening of the variable throttle;
A first port opening into the valve housing hole upstream of the variable throttle;
A second port that opens into the valve accommodation hole on the downstream side of the variable throttle, and
The variable pump according to claim 1 or 2, wherein the first pressure guide passage is connected to the first port, and the second pressure guide passage is connected to the second port. The pump element is
The tip of the vane slides on the cam ring as the rotor rotates so that the plurality of vanes can reciprocate,
The working fluid is discharged from a pump chamber defined between the adjacent vanes,
The variable pump according to any one of claims 1 to 3, wherein the cam ring is moved by a driving pressure guided from the control valve.

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