JP6043138B2 - Variable displacement vane pump - Google Patents

Description

  The present invention relates to a variable displacement vane pump used as a fluid pressure supply source in a fluid pressure device.

  A variable displacement vane 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.

  The variable displacement vane pump disclosed in Patent Document 1 is configured such that the discharge capacity is changed by the cam ring swinging around a support pin by a fluid pressure guided through a control valve.

  First and second fluid pressure chambers are provided on the outer periphery of the cam ring. Fluid pressure from the control valve is guided to the first and second fluid pressure chambers through the first and second fluid pressure passages. The cam ring swings due to the pressure difference between the first and second fluid pressure chambers.

  The first fluid pressure passage is provided through the adapter ring that houses the cam ring, and one end thereof opens to the inner periphery of the adapter ring and communicates with the first fluid pressure chamber.

  The second fluid pressure passage is provided in the housing with which the cam ring is slidably contacted, and the opening thereof opens to the end surface of the housing and communicates with the second fluid pressure chamber.

JP 2005-337146 A

  However, in the variable displacement vane pump disclosed in Patent Document 1, the opening of the second fluid pressure passage opens at the end face of the housing on which the cam ring slides and is partially blocked by the moving cam ring. There is a problem in that the hydraulic fluid flowing into and out of the second fluid pressure chamber through the second fluid pressure passage is subjected to pressure loss by the cam ring, and the operation responsiveness that the cam ring moves depending on the position of the cam ring is impaired.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to ensure operation responsiveness in which a cam ring moves in a variable displacement vane pump.

The present invention relates to a variable displacement vane pump used as a fluid pressure supply source in a fluid pressure device, an adapter ring provided in a housing space of a body, a cam ring movably provided inside the adapter ring, and a cam ring A rotor which is arranged on the inner side and is driven to rotate; and a plurality of vanes which are reciprocally movable in the rotor and define a pump chamber between the inner periphery of the cam ring, the outer periphery of the cam ring and the inner periphery of the adapter ring The first fluid pressure chamber and the second fluid pressure chamber , which are defined between them and to which the fluid pressure that causes the cam ring to be eccentric with respect to the rotor due to the pressure difference between each other, and an opening on the end surface of the housing that seals the housing space of the body and, Bei a first fluid pressure passage conducting fluid pressure to the first fluid pressure chamber, an opening in the end face of the housing, and a second fluid pressure passage for guiding the fluid pressure in the second fluid pressure chamber, the , At least one of the first peripheral region and a second peripheral region facing the second fluid pressure chamber facing the first fluid pressure chamber in the outer periphery of the cam ring, through the first fluid pressure passage or the second fluid pressure passage Guide the working fluid entering and exiting the first fluid pressure chamber or the second fluid pressure chamber , and prevent the opening end of the first fluid pressure passage or the opening end of the second fluid pressure passage from interfering regardless of the eccentric position of the cam ring. The guide recess is notched and formed.

In the present invention, when the discharge capacity of the variable displacement vane pump is changed, the working fluid entering and exiting the first fluid pressure chamber and the second fluid pressure chamber through the first fluid pressure passage and the second fluid pressure passage respectively flows to the outer peripheral surface of the cam ring. It is guided by a guide recess formed by being cut out. Accordingly, the first cam pressure passage and the second fluid pressure passage are prevented from being partially blocked by the moving cam ring, and the operating response of the cam ring moving is reduced by reducing the pressure loss exerted on the flow of the working fluid by the cam ring. Sex is secured.

1 is a front view of a variable displacement vane pump according to an embodiment of the present invention. It is sectional drawing which follows the AA line of FIG. It is a front view which shows the cam ring in a maximum eccentric position. It is a front view which shows the cam ring in a minimum eccentric position.

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

  A variable displacement vane pump 100 according to an embodiment of the present invention will be described with reference to FIGS.

  A variable displacement vane pump (hereinafter simply referred to as a “vane pump”) 100 is a hydraulic device (fluid pressure device) mounted on a vehicle, for example, a hydraulic pressure (fluid pressure) supply source such as a power steering device or a continuously variable transmission. It is used as

  Hereinafter, a configuration in which the vane pump 100 supplies hydraulic oil will be described. In addition, although the vane pump 100 uses working oil (oil) as a working fluid, you may use working fluid, such as a water-soluble alternative liquid, for example instead of working oil.

  In the vane pump 100, the power of an engine (not shown) is transmitted to the drive shaft 1, and the rotor 2 connected to the drive shaft 1 rotates. In FIG. 1, the rotor 2 rotates clockwise as indicated by the arrow.

  The vane pump 100 includes, as a pump mechanism that pressurizes hydraulic oil, a plurality of vanes 3 that can be reciprocated in the radial direction with respect to the rotor 2, and a cam ring 4 that houses the rotor 2 and the vanes 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.

  The vane pump 100 includes a pump body 5 as a body, a pump cover 6 as a housing, and a side plate 8. The pump body 5 and the pump cover 6 are fastened through a plurality of bolts 10. The drive shaft 1 is rotatably supported by the pump body 5 and the side plate 8 via bearings (not shown).

  The pump body 5 is formed with an accommodation space 15 for accommodating the pump mechanism. A side plate 8 that abuts against one side of the rotor 2 and the cam ring 4 is disposed on the bottom surface of the accommodation space 15. The opening of the accommodation space 15 is sealed by a pump cover 6 that abuts against the rotor 2 and the other side of the cam ring 4. The pump cover 6 and the side plate 8 are disposed with the adapter ring 11, the rotor 2, and the cam ring 4 sandwiched between both side surfaces. Since the adapter ring 11 is interposed between the pump cover 6 and the side plate 8, a gap between the pump cover 6 and the side plate 8 with respect to the rotor 2 and the cam ring 4 is formed with high accuracy.

  The side plate 8 is formed with a suction port 16 that guides hydraulic oil into the pump chamber 7 and a discharge port 18 that extracts the hydraulic oil in the pump chamber 7 and leads it to hydraulic equipment outside the vane pump 100. The suction port 16 communicates with a tank (not shown) through a suction passage (not shown). The discharge port 18 communicates with hydraulic equipment via a pump discharge passage (not shown).

  When the vane pump 100 is operated, 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. Inhaled. 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 the hydraulic oil pressurized in the pump chamber 7 is hydraulically supplied from the discharge port 18 through the pump discharge passage. Supplied to the equipment.

  Hereinafter, a configuration for changing the discharge capacity (displacement volume) of the vane pump 100 will be described.

An annular adapter ring 11 is accommodated in the accommodation space 15 of the pump body 5. A support pin 13 is interposed between the adapter ring 11 and the cam ring 4. An engagement recess 4 </ b> E that engages with the support pin 13 is formed on the outer periphery of the cam ring 4. 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. The cam ring 4 has end faces 4 </ b> D and 4 </ b> F that are orthogonal to the rotation center axis of the rotor 2. One end surface 4 </ b> D is in sliding contact with the end surface 6 </ b> A of the pump cover 6. The other end surface 4F is in sliding contact with the end surface 8A of the side plate 8.

  In the seal groove 11 </ b> A of the adapter ring 11, a seal material 14 is interposed in which the outer periphery of the cam ring 4 is in sliding contact with the cam ring 4 when it swings. Between the outer periphery of the cam ring 4 and the inner periphery of the adapter ring 11, the first fluid pressure chamber 31 and the second fluid pressure chamber 32 are partitioned by the support pin 13 and the sealing material 14. The outer peripheral surface of the cam ring 4 is divided into a first outer peripheral region 4B facing the first fluid pressure chamber 31 and a second outer peripheral region 4C facing the second fluid pressure chamber 32.

  The cam ring 4 swings about the support pin 13 by the pressure balance of the first fluid pressure chamber 31, the second fluid pressure chamber 32, and the pump chamber 7. As the cam ring 4 swings, the amount of eccentricity of the cam ring 4 with respect to the rotor 2 changes, and the discharge capacity of the pump chamber 7 changes. 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 vane pump 100 includes a control valve 21 that controls the pressure of hydraulic fluid guided to the first fluid pressure chamber 31 and the second fluid pressure chamber 32.

  The control valve 21 includes a valve housing hole 29 formed in the pump body 5 and a spool 22 that is slidably inserted into the valve housing hole 29. The spool 22 is configured to operate according to a pressure difference between the front and rear of a throttle portion (not shown) interposed in the pump discharge passage.

  The control valve 21 includes a first fluid pressure passage 33 communicating with the first fluid pressure chamber 31, a second fluid pressure passage 34 communicating with the second fluid pressure chamber 32, and a drain passage (not shown) communicating with the tank. And the pump discharge passage are connected to each other.

  The first fluid pressure passage 33 is formed across the pump body 5 and the pump cover 6. The first fluid pressure passage 33 is configured by through holes 41 and 42 and a recess 43 formed in the pump body 5 and through holes 44 and 45 formed in the pump cover 6. The through holes 41 and 42 of the pump body 5 extend coaxially with each other and are arranged in parallel with the rotation center axis of the rotor 2. The through holes 44 and 45 of the pump cover 6 extend in an inclined manner. The through hole 44 is disposed to be inclined with respect to the rotation center axis of the rotor 2. The through hole 45 is disposed in parallel with the rotation center axis of the rotor 2.

  A seal ring 46 is interposed at a joint portion between the pump body 5 and the pump cover 6. An annular groove 48 in which the seal ring 46 is interposed is formed on the end surface 5A of the pump body 5 so as to surround the recess 43. The seal ring 46 seals the connecting portion between the through hole 42 and the through hole 44 by the recess 43.

  Thus, since the first fluid pressure passage 33 is formed across the pump body 5 and the pump cover 6, it is possible to avoid being provided through the pump body 5 and the adapter ring 11. This prevents the oil pressure in the first fluid pressure passage 33 from escaping from the gap between the pump body 5 and the adapter ring 11, and the oil pressure from the control valve 21 passes through the first fluid pressure passage 33 to the first fluid pressure chamber 31. To be promptly guided.

  One end of the through hole 45 formed in the end surface 6 </ b> A of the pump cover 6 becomes the opening end 33 </ b> A of the first fluid pressure passage 33. The opening end 33 </ b> A extends in parallel with the rotation center axis of the rotor 2 and is formed to be orthogonal to the end surface 6 </ b> A of the pump cover 6.

  The opening diameter of the opening end 33 </ b> A is arbitrarily set according to the flow path cross-sectional area required for the first fluid pressure passage 33. However, in order to ensure a sufficient flow path cross-sectional area of the first fluid pressure passage 33, the minimum width of the first fluid pressure chamber 31 in which the opening diameter of the opening end 33 </ b> A is defined between the adapter ring 11 and the cam ring 4. Become bigger. For this reason, in the conventional apparatus, the cam ring closes a part of the opening end of the first fluid pressure passage while the cam ring is swung to the maximum eccentric position that maximizes the discharge capacity.

  In response to this, in the first outer peripheral region 4B of the cam ring 4, a first guide recess 47 that is recessed in a concave shape facing the open end 33A of the first fluid pressure passage 33 is formed.

  The first guide recess 47 is formed in a tapered groove shape whose depth gradually decreases with respect to the rotation center axis of the rotor 2. The first guide recess 47 has a groove base end 47 </ b> A that opens to the end face 4 </ b> D of the cam ring 4, and a groove tip end 47 </ b> B that opens to the first outer peripheral region 4 </ b> B of the cam ring 4. The depth of the first guide recess 47 gradually decreases from the groove base end 47A to the groove front end 47B. Thereby, it is suppressed that the cross section of the cam ring 4 is reduced by the 1st guide recessed part 47, and the intensity | strength of the cam ring 4 is ensured.

  The first guide recess 47 is formed in a groove shape having a circular cross section that is inclined with respect to the rotation center axis of the rotor 2. In a state where the cam ring 4 swings to the maximum eccentric position that maximizes the discharge capacity (see FIGS. 1 and 3A), the groove base end 47A of the first guide recess 47 is along the opening end 33A of the first fluid pressure passage 33. Thus, it is formed in an arc shape. Thus, the first guide recess 47 does not interfere with the opening end 33A of the first fluid pressure passage 33, and the bottom surface of the first guide recess 47 and the inner surface of the first fluid pressure passage 33 are continuous without a step.

  Similar to the first fluid pressure passage 33 described above, the second fluid pressure passage 34 is formed across the pump body 5 and the pump cover 6.

  A seal ring (not shown) is interposed at the mating portion of the pump body 5 and the pump cover 6, and the recess 53 provided in the connection portion between the through holes constituting the second fluid pressure passage 34 is sealed by this seal ring. The An annular groove 58 in which the seal ring is interposed is formed on the end surface 5A of the pump body 5.

  Thus, since the second fluid pressure passage 34 is formed across the pump body 5 and the pump cover 6, it can be avoided that the second fluid pressure passage 34 is provided through the pump body 5 and the adapter ring 11. This prevents the oil pressure in the second fluid pressure passage 34 from escaping from the gap between the pump body 5 and the adapter ring 11, and the oil pressure from the control valve 21 passes through the second fluid pressure passage 34 to the second fluid pressure chamber 32. To be promptly guided.

  In the second outer peripheral region 4 </ b> C of the cam ring 4, a second guide recess 57 that is recessed in a concave shape facing the opening end 34 </ b> A of the second fluid pressure passage 34 is formed.

  Similar to the first guide recess 47 described above, the second guide recess 57 is formed in a tapered groove shape whose depth gradually decreases with respect to the rotation center axis of the rotor 2. The second guide recess 57 has a base end 57 </ b> A that opens to the end face 4 </ b> D of the cam ring 4 and a tip (not shown) that opens to the second outer peripheral region 4 </ b> C of the cam ring 4. The depth of the second guide recess 57 gradually decreases from the base end 57A to the tip. Thereby, it is suppressed that the cross section of the cam ring 4 is reduced by the 2nd guide recessed part 57, and the intensity | strength of the cam ring 4 is ensured.

  The second guide recess 57 is formed in a groove shape having a circular cross section that is inclined with respect to the rotation center axis of the rotor 2. In a state where the cam ring 4 is swung to the minimum eccentric position that minimizes the discharge capacity (see FIG. 3B), the base end 57A of the second guide recess 57 is circular so as to follow the open end 34A of the second fluid pressure passage 34. It is formed in an arc shape. Thus, the second guide recess 57 does not interfere with the open end 34A of the second fluid pressure passage 34, and the bottom surface of the second guide recess 57 and the inner surface of the second fluid pressure passage 34 are continuous without a step.

  The first guide recess 47 and the second guide recess 57 are formed so as to be lined up with the support pin 13 interposed therebetween. The first guide concave portion 47 and the second guide concave portion 57 are disposed in the same radial direction as the control valve 21 with respect to the rotation center axis of the rotor 2, and the first fluid pressure passage 33 and the second fluid pressure passage 34 that connect them are arranged. The passage length is shortened.

  The first guide recess 47 and the second guide recess 57 are formed integrally with the cam ring 4 formed by sintering. Not limited to this, the first guide recess 47 and the second guide recess 57 may be formed in the molded cam ring 4 by cutting.

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

  When the rotational speed of the rotor 2 is low, such as when the pump is started, the low pressure from the drain passage communicating with the tank is guided to the first fluid pressure chamber 31 through the first fluid pressure passage 33, and the second fluid pressure chamber 32. The pump discharge pressure is guided through a throttle passage (not shown). As a result, the cam ring 4 swings in the direction in which the discharge capacity of the pump chamber 7 increases due to the pressure difference between the hydraulic oil in the first fluid pressure chamber 31 and the second fluid pressure chamber 32, as shown in FIG. The first outer peripheral region 4B comes into contact with the bulging portion 11B on the inner periphery of the adapter ring 11 and is held at the maximum eccentric position where the amount of eccentricity with respect to the rotor 2 is maximized.

  In the state where the cam ring 4 is at the maximum eccentric position, the vane pump 100 discharges the hydraulic oil with the maximum discharge capacity, and the flow rate of the hydraulic oil discharged from the vane pump 100 increases substantially in proportion to the rotational speed of the rotor 2. Thereby, even when the rotational speed of the rotor 2 is low, it is possible to supply a sufficient amount of hydraulic oil to the hydraulic equipment.

  As the rotational speed of the rotor 2 increases and the pressure difference between the front and rear of the throttle portion interposed in the pump discharge passage increases, the control valve 21 causes the spool 22 to resist the urging force of the return spring (not shown). And the opening at which the pump discharge passage and the first fluid pressure passage 33 communicate with each other is adjusted, and the opening at which the drain passage (not shown) and the second fluid pressure passage 34 communicate with each other is adjusted. As a result, the hydraulic oil in the pump discharge passage flows into the first fluid pressure chamber 31 through the first fluid pressure passage 33. On the other hand, the hydraulic oil in the second fluid pressure chamber 32 flows out through the second fluid pressure passage 34 and is discharged from the control valve 21 to the tank through the drain passage. 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 decreases, the second outer peripheral region 4C of the cam ring 4 comes into contact with the bulging portion 11C on the inner periphery 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.

  Thus, the control valve 21 operates according to the pressure difference between the front and rear of the throttle portion interposed in the pump discharge passage, so that the discharge capacity of the vane pump 100 is adjusted to be substantially constant even when the rotational speed of the rotor 2 increases. The Thereby, the pressure of the hydraulic fluid supplied with respect to hydraulic equipment at the time of driving | running | working of a vehicle is adjusted moderately.

  FIG. 3A is a front view showing a state where the cam ring 4 is at the maximum eccentric position. In this state, the first guide recess 47 is disposed so as not to interfere with the opening end 33 </ b> A of the first fluid pressure passage 33. As the cam ring 4 swings in the direction of decreasing the discharge capacity from this state, the first guide recess 47 moves away from the opening end 33 </ b> A of the first fluid pressure passage 33. Even when the cam ring 4 moves in this manner, the opening end 33A of the first fluid pressure passage 33 is prevented from being partially blocked by the cam ring 4, and the flow path area of the first fluid pressure passage 33 is ensured. . As a result, when the cam ring 4 swings and the discharge capacity is changed, the pressure loss imparted by the cam ring 4 to the flow of hydraulic oil entering and exiting the first fluid pressure chamber 31 from the first fluid pressure passage 33 is suppressed. Therefore, the operating hydraulic pressure is promptly guided to the first fluid pressure chamber 31.

  FIG. 3B is a front view showing a state where the cam ring 4 is at the minimum eccentric position. In this state, the second guide recess 57 is arranged so as not to interfere with the open end 34 </ b> A of the second fluid pressure passage 34. As the cam ring 4 swings in the direction of decreasing the discharge capacity from this state, the second guide recess 57 is separated from the open end 34 </ b> A of the second fluid pressure passage 34. Even when the cam ring 4 moves in this manner, the opening end 34A of the second fluid pressure passage 34 is prevented from being partially blocked by the cam ring 4, and the flow area of the second fluid pressure passage 34 is ensured. . Thereby, when the cam ring 4 swings and the discharge capacity is changed, the pressure loss imparted by the cam ring 4 to the flow of hydraulic oil flowing out from the second fluid pressure chamber 32 through the second fluid pressure passage 34 is suppressed. Therefore, the operating hydraulic pressure is promptly guided to the second fluid pressure chamber 32.

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

[1] On the outer periphery of the cam ring 4 of the vane pump 100, a guide recess for guiding the working fluid entering and exiting the first fluid pressure chamber 31 and the second fluid pressure chamber 32 through the first fluid pressure passage 33 and the second fluid pressure passage 34. Since 47 and 57 are formed by cutting out, when the discharge capacity of the vane pump 100 is changed, the first fluid pressure passage 33 and the second fluid pressure passage 34 may be partially blocked by the moving cam ring 4. As a result, the working fluid quickly enters and exits the first fluid pressure chamber 31 and the second fluid pressure chamber 32 through the first fluid pressure passage 33 and the second fluid pressure passage 34, and the operation responsiveness to move the cam ring 4 is ensured. Is done.

  [2] A support pin 13 that supports the cam ring 4 so as to be swingable with respect to the adapter ring 11 is provided. In the first fluid pressure chamber 31, the cam ring 4 is placed in a direction in which the discharge capacity decreases through the first fluid pressure passage 33. The first guiding recess 47 formed in the first outer peripheral region 4B is guided by the fluid pressure to be swung, and the first fluid pressure passage 33 is swung to the maximum eccentric position where the cam ring 4 maximizes the discharge capacity. The opening end 33A of the first fluid pressure passage 33 is prevented from being partially blocked by the cam ring 4 even when the cam ring 4 is moved. As a result, the working fluid quickly enters and exits the pressure chamber 31 to ensure the operation responsiveness of the cam ring 4 moving.

  [3] A support pin 13 that supports the cam ring 4 so as to be swingable with respect to the adapter ring 11 is provided. In the second fluid pressure chamber 32, the cam ring 4 is disposed in a direction in which the discharge capacity increases through the second fluid pressure passage 34. The second guide recess 57 formed in the second outer peripheral region 4C is guided with the fluid pressure to be swung, and the second fluid pressure passage 34 is swung to the minimum eccentric position where the cam ring 4 minimizes the discharge capacity. Therefore, even if the cam ring 4 moves, the opening end 34A of the second fluid pressure passage 34 is prevented from being partially blocked by the cam ring 4, and the second fluid The working fluid quickly enters and exits the pressure chamber 32, and the operation responsiveness that the cam ring 4 moves is ensured.

  [4] The guide recesses 47 and 57 are formed in a groove shape inclined with respect to the rotation center axis of the rotor 2, and have groove base ends 47 </ b> A and 57 </ b> A that open on the end face 4 </ b> D of the cam ring 4 and openings on the outer peripheral surface of the cam ring 4. Since the working fluid quickly enters and exits the fluid pressure chambers 31 and 32, the operation responsiveness to move the cam ring 4 is secured, and the strength of the cam ring 4 is secured. Can be compatible.

  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, the suction pressure of the working oil sucked into the pump chamber 7 is always led to the first fluid pressure chamber 31, and the control valve 21 controls the pressure of the working fluid led from the pump chamber 7 to the second fluid pressure chamber 32, 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 decreases (rightward in FIG. 1). The cam ring 4 swings in the direction in which the discharge capacity increases (leftward in FIG. 1) when the fluid pressure guided to the second fluid pressure chamber 32 through the control valve 21 is increased. Also good.

  Further, the configuration is not limited to the configuration in which the support pins 13 that support the cam ring 4 so as to be swingable with respect to the adapter ring 11 are provided. For example, the cam ring 4 may be configured to slide and move with respect to the adapter ring 11.

  Further, a guide recess for guiding the working fluid entering and exiting the fluid pressure chambers 31 and 32 through the fluid pressure passages 33 and 34 may be formed on the inner periphery of the adapter ring 11. Thereby, the flow area of the fluid pressure passages 33 and 34 can be enlarged, and the operation responsiveness that the cam ring 4 moves can be improved.

  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 4B First outer peripheral area 4C Second outer peripheral area 4D End face 5 Pump body (body)
6 Pump cover (housing)
6A End surface 7 Pump chamber 11 Adapter ring 13 Support pin 15 Housing space 31 First fluid pressure chamber 32 Second fluid pressure chamber 33 First fluid pressure passage 33A Open end 34 Second fluid pressure passage 34A Open end 47 First guide recess ( (Guide recess)
47A Groove base end 47B Groove tip 57 Second guide recess (guide recess)
100 Variable displacement vane pump

Claims (4)

A variable displacement vane pump used as a fluid pressure supply source in a fluid pressure device,
An adapter ring provided in the housing space of the body;
A cam ring movably provided inside the adapter ring;
A rotor disposed inside the cam ring and driven to rotate;
A plurality of vanes provided in the rotor so as to be capable of reciprocating and defining a pump chamber with an inner periphery of the cam ring;
A first fluid pressure chamber and a second fluid pressure chamber, which are defined between an outer periphery of the cam ring and an inner periphery of the adapter ring, and in which a fluid pressure for decentering the cam ring with respect to the rotor is guided by a pressure difference between the cam ring and the adapter ring; ,
Open to the end face of the housing for sealing the accommodation space of the body, a first fluid pressure passage conducting fluid pressure to the first fluid pressure chamber,
A second fluid pressure passage that opens at an end surface of the housing and guides a fluid pressure to the second fluid pressure chamber ,
At least one of the first outer peripheral area facing the first fluid pressure chamber and the second outer peripheral area facing the second fluid pressure chamber on the outer periphery of the cam ring has the first fluid pressure passage or the second fluid pressure. with guiding the working fluid to and from the first fluid pressure chamber or the second fluid pressure chamber through the through passage, the open end or the second fluid in the first fluid pressure passage regardless eccentric position of said cam ring A variable displacement vane pump, characterized in that a guide recess is cut out so that the opening end of the pressure passage does not interfere . A support pin for swingably supporting the cam ring with respect to the adapter ring;
The first fluid pressure chamber is guided with a fluid pressure that causes the cam ring to swing in a direction in which the discharge capacity decreases through the first fluid pressure passage.
As the guide recess, a first guide recess is formed in the first outer peripheral region,
The first guide recess is disposed so as not to interfere with an opening end of the first fluid pressure passage when the cam ring is swung to a maximum eccentric position that maximizes a discharge capacity. 2. The variable displacement vane pump according to 1. A support pin for swingably supporting the cam ring with respect to the adapter ring;
The second fluid pressure chamber is guided with a fluid pressure that causes the cam ring to swing in a direction in which the discharge capacity increases through the second fluid pressure passage.
As the guide recess, a second guide recess is formed in the second outer peripheral region,
The second guide recess is disposed so as not to interfere with an opening end of the second fluid pressure passage when the cam ring is swung to a minimum eccentric position that minimizes a discharge capacity. The variable displacement vane pump according to 1 or 2.   The variable displacement vane pump according to any one of claims 1 to 3, wherein the guide recess is formed in a groove shape inclined with respect to a rotation center axis of the rotor.

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