JP5060444B2 - Variable displacement vane pump - Google Patents

Description

  The present invention relates to a variable displacement vane pump capable of adjusting a displacement volume by elastic deformation of a ring surrounding a pump chamber.

  Conventionally, what is described in Patent Document 1 is known as an elastic deformation type variable displacement vane pump as described above. The outline is shown in FIG.

  The vane pump includes a rotor 2 that holds a plurality of vanes 1, an inner ring 3 that has an inner peripheral surface that can slide in contact with the tip of each vane 1, and a pair of pressures that are disposed on both the left and right sides of the inner ring 3. The plate 4, the fixed housing 5 that holds the pressure plate 4 so that the pressure plate 4 can slide in the direction in which the pressure plate 4 comes in contact with and away from the pressure plate 4, and the pressure plates 4 in opposite directions (that is, in the direction in which the pressure plate 4 comes in contact with and away from And a driving device 6 to be slid.

  Each vane 1 forms a pump chamber between the vane 1 adjacent thereto. The fixed housing 5 has a pair of suction ports 7 that open from the side to the pump chamber at predetermined positions (upper left position and lower right position in the figure), and from these suction ports 7 in the rotor rotational circumferential direction. A pair of discharge ports 8 are formed which open from the side with respect to the pump chamber located at the position (upper right position and lower left position in the figure).

  The inner peripheral surface of the inner ring 3 is substantially circular when the inner ring 3 is not deformed. Therefore, the displacement volume in this state is almost zero. From this state, the pressure plates 4 are driven in a direction approaching each other to press the inner ring 3 inward from the left and right, whereby the inner ring 3 is elastically deformed in a vertically long direction in the figure. As the degree of deformation increases, that is, as the degree of flatness of the inner peripheral surface of the inner ring 3 increases, the displacement volume, that is, the pump discharge capacity increases.

Specifically, by rotating the rotor 2 in the clockwise direction in the figure with the inner ring 3 deformed, the pump chambers move from the suction port 7 to the next discharge port 8, The volume of the pump chamber increases rapidly in the region communicating with the suction port 7 and then decreases rapidly in the region reaching the discharge port 8. Accordingly, the fluid introduced into the suction port 7 is sucked into the pump chamber due to the increase in the volume of the pump chamber, and then discharged from the discharge port 8 to the outside of the pump at a high pressure due to the decrease in the volume of the pump chamber. The displacement volume increases as the volume change of each pump chamber increases, and the volume change is governed by the degree of deformation (flatness) of the inner ring 3.
JP-A-4-31680

  In the vane pump, the inner peripheral surface of the upper and lower end portions of the pressure plate 4 and the outer periphery of the inner ring 3 are allowed in order to allow deformation (bulging in the vertical direction) of the inner ring 3 due to pressing of the pressure plate 4. An appropriate gap 9 is provided in advance with the surface. In the region where the gap 9 exists, the inner ring 3 is not supported by the pressure plate 4, and therefore the shape of the inner ring 3 becomes unstable, which may adversely affect the discharge performance of the pump. In particular, the region where the gap 9 exists is a region where the pump chamber moves from the suction port 7 to the discharge port 8, and the shape of the inner peripheral surface of the inner ring 3 in this region has a great influence on the pump performance. Moreover, it is difficult to accurately reproduce the inner peripheral surface shape in this region by elastic deformation of the inner ring 3.

  In view of such circumstances, the present invention is capable of changing the displacement volume due to elastic deformation of the inner ring surrounding the pump chamber, and is high by keeping the shape of the inner ring stable regardless of the elastic deformation. An object of the present invention is to provide a variable displacement vane pump capable of maintaining the pump performance.

  As means for solving the above-mentioned problems, a variable displacement vane pump according to the present invention has a cylindrical outer peripheral surface and is driven to rotate around the central axis of the outer peripheral surface, and the rotational circumferential direction of the rotor A plurality of vanes that are disposed at a distance from each other, protrude outwardly in the rotational radial direction from the outer peripheral surface of the rotor, and are held by the rotor so as to be relatively displaceable in the rotational radial direction, A plurality of pump chambers defined by the vanes are defined between the inner peripheral surface and the outer peripheral surface of the rotor. The inner peripheral surface has an inner peripheral surface that is in sliding contact with the tip of each vane. An inner ring that can be elastically deformed so as to be displaced inward in the rotational radial direction of the rotor, an outer holding member that holds the inner ring from the outer side in the rotational radial direction of the rotor, and the pump chambers of the rotor. rotation A suction port that surrounds both sides of the direction and opens from the side with respect to the pump chamber at a specific position, and from the side with respect to the pump chamber at a position away from the suction port downstream in the rotational direction of the rotor A side housing having a discharge port that opens; and a volume operation means for changing the displacement volume by elastically deforming the inner ring and displacing the inner circumferential surface thereof, and the inner circumferential surface of the inner ring includes The inner ring has a shape having a maximum diameter in the vicinity of the end of the suction port so that the inner ring changes along the rotational circumferential direction of the rotor and the displacement volume becomes maximum when the inner ring is not deformed. The outer holding member is in contact with the outer surface of a part of the inner ring including a region from the end of the suction port to the start of the discharge port. And an outer movable member that is displaceable in the rotational radial direction of the rotor, and an outer fixing member that is fixed so as to contact an outer surface of a portion of the inner ring other than a portion that contacts the outer movable member. The capacity operation means is configured to displace the outer movable member inward in the rotational radial direction of the rotor and elastically displace the portion of the inner ring in contact with the outer movable member radially inward. The flatness of the inner peripheral surface of the inner ring and the displacement volume are reduced.

  In this variable displacement vane pump, the inner ring is supported in a stable state by the outer holding member regardless of the elastic deformation of the inner ring, so that the shape of the inner ring is stable, which is a high pump performance. Make it possible. Specifically, unlike the inner ring 3 of the conventional variable displacement vane pump shown in FIG. 6, the inner ring has an inner peripheral surface shape that realizes the maximum displacement volume in an undeformed state, Since the inner peripheral surface is displaced inward in the rotor rotational radial direction by being elastically deformed by receiving a pressure by the outer movable member from this state, the displacement volume is particularly reduced among the inner ring. The portion that affects the characteristics, that is, the portion of the region from the suction port to the discharge port is always constrained from the outside by the outer movable member, and this stabilizes the shape of the inner peripheral surface of the inner ring. . Therefore, the setting of the shape of the inner peripheral surface becomes easy.

  For example, the shape of the inner peripheral surface of the inner ring is designed such that the inner diameter of the inner ring is maximized near the end of the suction port and the inner diameter gradually decreases until reaching the start end of the discharge port. Such a shape greatly contributes to prevention of cavitation. That is, in the vane pump, cavitation may occur if the suction of the fluid cannot catch up with the movement of the vane from the suction stroke to the discharge stroke. However, the shape of the inner peripheral surface of the inner ring as described above is It is possible to make up for a shortage of the inflow of fluid by gradually decreasing the volume of the chamber after the volume of the chamber is maximized, thereby effectively suppressing cavitation. And in the variable displacement vane pump according to the present invention, it is possible to obtain the shape as described above with high accuracy.

  Further, if at least the inner peripheral portion of the outer fixing member is formed of an elastic body that can be elastically deformed so as to maintain contact with the outer peripheral surface of the inner ring regardless of elastic deformation of the inner ring. Even in the arrangement region of the outer fixing member, the shape of the inner ring can be made more stable regardless of its elastic deformation.

  Further, the variable displacement vane pump according to the present invention has a plurality of suction ports and a plurality of discharge ports, unlike a vane pump of a type in which the displacement is changed by swinging the cam ring surrounding the pump chamber and changing the eccentric amount thereof. It is possible to have. For example, the side housing has a first suction port and a second suction port at positions facing each other across the rotation center axis of the rotor as the suction port, and the first suction port as the discharge port. And a first discharge port and a second discharge port at positions downstream of the second suction port, respectively, and the outer holding member is a part of the inner ring as the outer movable member, and A first movable member that contacts an outer surface of a portion including a region from the suction port to the first discharge port, and a part of the inner ring that extends from the second suction port to the second discharge port. What is necessary is just to have the 2nd movable member which contacts the outer surface of the part containing the area | region until. Thus, the vane pump in which the suction port and the discharge port are divided can reduce the size, weight, and driving torque as compared with a pump having only a single suction port and a single discharge port.

  As described above, in the variable displacement vane pump according to the present invention, the inner ring for defining the pump chamber has a shape that maximizes the displacement volume in the non-deformed state, and is movable outside in contact with the inner ring. Since the displacement of the member is reduced by elastically deforming the inner ring by displacing the member inward in the rotor radial direction, the inner peripheral surface shape of the inner ring can be stabilized regardless of the elastic deformation. Higher pump performance can be maintained.

  A preferred embodiment of the present invention will be described with reference to FIGS.

  1 to 4 show a variable displacement vane pump according to an embodiment of the present invention. This vane pump is connected to a motor (not shown) and is driven to rotate about its own axis, a rotor 12 fixed to the drive shaft 10, and a plurality of vanes 14 held by the rotor 12. The inner ring 16 surrounding the rotor 12 and the vane 14, the outer holding member 18 that holds the inner ring 16 from the outside, the side housing 20, and the capacity operation device 22 are provided.

  The drive shaft 10 passes through the central portion of the rotor 12, and the rotor 12 is fixed to the drive shaft 10 in the through state. The rotor 12 has a cylindrical outer peripheral surface 12 a that is coaxial with the drive shaft 10, and is driven to rotate about the central axis integrally with the drive shaft 10.

  Each of the vanes 14 is formed of a thin plate material, and is disposed at a distance from each other in the rotational circumferential direction of the rotor 12, and protrudes outward in the rotational radial direction from the outer peripheral surface 12 a of the rotor 12. It is attached to the rotor 12 so as to be relatively displaceable in the rotational radial direction, and rotates together with the rotor 12.

  The inner ring 16 has an inner peripheral surface 16 a that is in sliding contact with the tip of each vane 14, and is defined by the vanes 14 between the inner peripheral surface 16 a and the outer peripheral surface 12 a of the rotor 12. A plurality of pump chambers are defined. The inner ring 16 according to this embodiment is composed of an endless thin plate material, and the inner peripheral surface 16a is elastically deformable so as to be displaced inward in the rotational radial direction of the rotor 12. The wall thickness is set small.

  As shown in FIG. 4, the side housing 20 surrounds each pump chamber from both sides in the rotational axis direction of the rotor 12 (longitudinal direction of the drive shaft 10; vertical direction in FIG. 4). 14 and the respective rings 16 and 18, and in this embodiment, comprises a pump body 24, a side plate 25, and a pump cover 26.

  The pump body 24 includes a side wall 24a and a peripheral wall 24b extending laterally from the outer peripheral portion of the side wall 24, and the side wall 24a and the peripheral wall 24b surround a recess that opens laterally. Then, the side plate 25 is fitted into the back side of the recess, the rotor 12 and both rings 16 and 18 are fitted to the outside thereof, and the pump cover 26 is attached to the outside thereof. Accordingly, each pump chamber is surrounded by the inner surface of the side plate 25 and the inner surface of the pump cover 26 from both outer sides in the rotation axis direction of the rotor 12. The side housing 20 rotatably supports the drive shaft 10 with the drive shaft 10 penetrating through the side housing 20.

  The pump body 24 is provided with a fluid suction port (not shown) for sucking fluid (oil in this embodiment) from the outside of the pump and a fluid discharge port 28 for discharging fluid to the outside of the pump. The pump cover 26 is formed with a first suction port 31 and a second suction port 32, and a first discharge port 33 and a second discharge port 34. Both the suction ports 31 and 32 are connected to the fluid suction port via a passage (not shown), and both the discharge ports 33 and 34 are connected to the fluid discharge port 28 via a passage (not shown).

  Each of the ports 31 to 34 is formed at a position opening from the side with respect to the pump chamber at a predetermined position. Specifically, the first suction port 31 opens from the side with respect to the pump chamber at a specific position (the upper left position of the drive shaft 10 in FIG. 1), and the second suction port 32 is the drive It opens from the side with respect to the pump chamber at a position opposite to the first suction port 31 with respect to the shaft 10 (that is, a position spaced apart from the first suction port 31 in the rotational circumferential direction of the rotor 12 by 180 °). . The first discharge port 33 opens from the side to the pump chamber at a position about 90 ° away from the first suction port 31 downstream in the rotation direction of the rotor 12 (clockwise direction in FIG. 1). Similarly, the second discharge port 34 opens from the side into the pump chamber at a position spaced about 90 ° from the second suction port 32 downstream in the rotational direction.

  The inner peripheral surface 16a of the inner ring 16 has a shape in which the inner diameter of the inner ring 16 changes along the rotational circumferential direction of the rotor 12, and the displacement volume of the pump is not changed when the inner ring 16 is not deformed. The inlet ports 31 and 32 have a shape having a maximum diameter in the vicinity of the ends 31a and 32a (FIG. 3) so as to be maximized. That is, in this embodiment, it has a major axis in the substantially vertical direction and a flat shape in the substantially horizontal direction.

  More specifically, the inner peripheral surface 16a has a cam profile as shown in FIG. This cam profile shows the relationship between the rotation angle θ (0 ° ≦ θ ≦ 180 °) in the traveling direction and the radius at the rotation angle position, starting from the left end position and the right end position in FIG. It is. As shown in the figure, the radius of the inner peripheral surface 16a suddenly increases from the starting point at the position of θ = 0 ° toward the rotor rotation direction, and at the position of θ≈60 ° (at each of the suction ports 31, 32). It has a characteristic that it reaches a peak at a position near the end points 31a and 32a), and then gradually decreases to a position of θ≈120 ° (a position near the start ends 33a and 34a of the discharge ports 33 and 34), and rapidly decreases from the position. Have.

  The outer holding member 18 is disposed around the inner ring 16 and is restrained and fixed by an outer movable member that can be displaced in the radial direction of the rotor 12 and the peripheral wall 24b of the pump body 24. And an outer fixing member. In this embodiment, the outer movable member is constituted by a first movable member 35 and a second movable member 36 respectively disposed above and below the inner ring 16, and the outer fixing member is a left and right of the inner ring 16. The first fixing member 37 and the second fixing member 38 are arranged respectively.

  As shown in FIG. 3, the first movable member 35 includes a region above the inner ring 16 and extending from the end 31 a of the first suction port 31 to the start end 33 a of the first discharge port 33. The second movable member 36 is located under the inner ring 16 from the terminal end 32a of the second suction port 32 to the second discharge port 34. It has an inner side surface 36a shaped so as to come into contact with the outer side surface of the portion including the region up to the start end 34a.

  As will be described in detail later, these movable members 35 and 36 are slidably driven inward in the rotor rotational radial direction by the capacity operation device 22, whereby the upper portion and the lower portion of the inner ring 16 are respectively connected to the rotor. It is pressed from the outside in the direction of the rotational diameter and elastically displaced inward in the same direction.

  The first fixing member 37 is a left portion (portion on the first suction port 31 and second discharge port 34 side) of the inner ring 16 shown in FIGS. It fixes to the position which contacts the outer peripheral surface of parts other than the part which contacts. Specifically, the first fixing member 37 has a fixing member main body 37a having a groove as shown in FIG. 4 on the inner peripheral surface, and is fitted in the groove of the fixing member main body 37a so as to face inward from the fixing member main body 37a. And an elastic body 37b protruding from the bottom. The elastic body 37 b constitutes an inner peripheral portion of the first fixing member 37, has an inner peripheral surface having a shape that substantially matches the outer peripheral surface of the left side portion of the inner ring 16, and the inner ring 16. Regardless of the elastic deformation, the elastic deformation is performed so as to maintain the contact between the outer peripheral surface of the inner ring 16 and the inner peripheral surface of the elastic body 37b.

  The second fixing member 38 is a right portion (portion on the second suction port 32 and first discharge port 33 side) of the inner ring 16 shown in FIGS. 1 to 3, and the both outer movable members 35, 36. It fixes to the position which contacts the outer peripheral surface of parts other than the part which contacts. Similarly to the first fixing member 37, the second fixing member 38 is also fitted into the fixing member main body 38a having a groove as shown in FIG. 4 on the inner peripheral surface, and the fixing member main body 38a. The elastic body 38b protrudes inward from the main body 38a. The elastic body 38b constitutes an inner peripheral portion of the second fixing member 38, has an inner peripheral surface having a shape that substantially matches the outer peripheral surface of the right side portion of the inner ring 16, and the inner ring 16 Regardless of the elastic deformation, the elastic deformation is performed so as to maintain the contact between the outer peripheral surface of the inner ring 16 and the inner peripheral surface of the elastic body 38b.

  The capacity operating device 22 is configured to slide the movable members 35 and 36 in the rotor radial direction (vertical direction in this embodiment) in order to adjust the pump discharge capacity by using elastic deformation of the inner ring 16. To do. The capacity operation device 22 according to this embodiment uses a fluid discharge pressure (hydraulic pressure) from the fluid discharge port 28 as a drive source, and a first hydraulic pressure for operating the first movable member 35. A cylinder 40A, a second hydraulic cylinder 40B for operating the second movable member 36, a hydraulic circuit 50 for simultaneously operating the hydraulic cylinders 40A and 40B using the hydraulic pressure, and a controller 60. Prepare.

  Both the hydraulic cylinders 40A and 40B are incorporated in the pump body 24, and are respectively disposed on both outer sides (upper and lower sides) of the movable members 35 and 36, respectively, and the pistons 42A. , 42B and rods 44A, 44B extending inward in the rotor rotational radial direction and connected to the movable members 35, 36, respectively. On the other hand, the pump body 24 is formed with cylinder chambers 46A and 46B for accommodating the pistons 44 and rod insertion holes 48A and 48B through which the rods 44A and 44B are inserted.

  The hydraulic circuit 50 includes a branch port 29 formed in the fluid discharge port 28, and an oil passage 52 that connects the branch port 29 and the piston chambers 46A and 46B (in FIG. 1, for convenience, a portion reaching the piston chamber 46A). Only), a throttle 54 provided in the middle of the oil passage 52, and a head side chamber of the piston chamber 46A, 46B in the middle of the oil passage 52 (that is, opposite to the rods 44A, 44B). And an electromagnetic proportional pressure reducing valve 56 provided between the two chambers. The electromagnetic proportional pressure reducing valve 56 has a solenoid 58, and this solenoid 58 applies a secondary pressure (that is, a hydraulic pressure applied to the head side chambers of the piston chambers 46A and 46B) proportional to the electrical signal input to the solenoid 58. The opening degree of the electromagnetic proportional pressure reducing valve 56 is changed so as to be generated.

  The hydraulic circuit 50 may be constructed outside the pump, but may be incorporated in the pump body 24, for example. In this case, all of the oil passage 52, the throttle 54, and the valve chamber of the electromagnetic proportional pressure reducing valve 56 may be formed in the pump body 24. The solenoid 58 of the electromagnetic proportional pressure reducing valve 56 is shown by a broken line 58 'in FIG. It only has to be installed at a position where

  The controller 60 is composed of a microcomputer or the like and receives an input of a command signal for designating a pump discharge capacity. Then, an electric signal for obtaining the designated pump discharge capacity is input to the solenoid 58 of the electromagnetic proportional pressure reducing valve 56.

  Next, the operation of this variable displacement vane pump will be described.

  In this vane pump, when the drive shaft 10 is rotationally driven in the clockwise direction of FIG. 1, the rotor 12 rotates integrally with the drive shaft 10, and each vane 14 held by the rotor 12 The rotor 14 moves in the rotational direction of the rotor 12 while maintaining the contact between the distal end portion of the vane 14 and the inner peripheral surface 16a of the inner ring 16 (that is, while sliding in contact with the inner peripheral surface 16a). Thereby, the pump chamber formed between the mutually adjacent vanes 14 also moves in the rotation direction.

  At this time, since the inner peripheral surface 16a of the inner ring 16 has a cam profile as shown in FIG. 5, the fluid (oil) introduced into each suction port 31, 32 is sucked into each pump chamber and pressurized. It is discharged to the discharge ports 33 and 34, respectively. Specifically, each of the pump chambers expands in a region where each of the suction ports 31 and 32 is opened in the pump chamber, and fluid is sucked from the suction ports 31 and 32 by this expansion. The pump chamber past the terminal ends 31a and 32a of the suction ports 31 and 32 contracts little by little as the rotor rotates, and then rapidly contracts after reaching the start ends 33a and 34a of the discharge ports 33 and 34. As a result, the fluid in the pump chamber is discharged from the discharge ports 33 and 34 to the outside of the pump through the fluid discharge port 28.

  On the other hand, the controller 60 outputs an electrical signal corresponding to the command signal input to the controller 60 toward the solenoid 58 of the electromagnetic proportional pressure reducing valve 56. Upon receiving this electrical signal, the solenoid 58 makes both hydraulic pressures so that the pump discharge capacity specified by the command signal can be obtained by setting the opening of the electromagnetic proportional pressure reducing valve 56 to an opening proportional to the electrical signal. The cylinders 40A and 40B and the outer movable members 35 and 36 are operated.

  For example, when the pump discharge capacity specified by the command signal is the maximum capacity, the controller 60 minimizes the electric signal (including 0), and thereby closes the electromagnetic proportional pressure reducing valve 56. The closing of the electromagnetic proportional pressure reducing valve 56 minimizes the head side pressure of the piston chambers 46A and 46B, in other words, the back pressure of the pistons 42A and 42B stored in the piston chambers 46A and 46B. As a result, the pistons 42A and 42B, the rods 44A and 44B, and the outer movable members 35 and 36 are pushed outward in the rotor radial direction to the stroke limit by the elastic return force of the inner ring 16 and the elastic bodies 37b and 38b. The inner ring 16 is not deformed or close to it. In this state, the deformation degree of the inner ring 16 is the smallest and the flatness degree (the ratio of the length of the major axis to the length of the minor axis) is the largest, so that the displacement and discharge capacity of the pump are maximum. Become.

  On the other hand, when the pump discharge capacity specified by the command signal is smaller than the maximum capacity, the controller 60 increases the electrical signal corresponding to the difference. This electric signal activates the solenoid 58 so as to increase the opening of the electromagnetic proportional pressure reducing valve 56 and increase the head side pressure of each piston chamber 46A, 46B by that amount. This head side pressure slides the pistons 42A and 42B, the rods 44A and 44B, and the outer movable members 35 and 36 stored in the piston chambers 46A and 46B inwardly in the rotor radial direction, thereby causing upper and lower portions ( The portions extending from the suction ports 31 and 32 to the discharge ports 33 and 34 are elastically displaced inward in the radial direction. As a result, the flatness of the inner ring 16 is lowered, and the displacement and discharge capacity of the pump are reduced accordingly.

  In the vane pump described above, regardless of the elastic deformation of the inner ring 16, the inner ring 16 is always supported in a stable state from the outside by the outer holding member 18 (movable members 35 and 36 and fixed members 37 and 38). Therefore, the shape of the inner peripheral surface 16a of the inner ring 16 is stabilized, and this makes it possible to ensure high pump performance.

  For example, the conventional variable displacement vane pump shown in FIG. 6 increases the displacement volume by increasing the amount of expansion of the inner ring 3 in the vertical direction by pressing the inner ring 3 from the left and right directions by the pressure plate 4. Therefore, the shape of the upper and lower portions of the inner ring 3 that tends to affect the pump performance tends to become unstable. Therefore, it is difficult to obtain a stable pump performance.

  On the other hand, in the vane pump shown in FIGS. 1 to 5, the inner ring 16 has a shape of the inner peripheral surface in advance so as to realize the maximum displacement volume in a non-deformed state. Since the inner circumferential surface is displaced inward in the rotor rotational radial direction by being elastically deformed by receiving the pressure by the members 35 and 36, the displacement volume is reduced. The affected part, that is, the part of the region from the suction port to the discharge port (upper and lower parts in FIG. 1) is always constrained from the outside by the inner side surfaces 35a and 36a of the outer movable members 35 and 36. This stabilizes the shape of the inner peripheral surface 16 a of the inner ring 16.

  This further contributes to the improvement of the pump characteristics because the shape of the inner peripheral surface 16 can be set easily and with high accuracy. For example, as shown in FIG. 5, the shape (cam profile) of the inner peripheral surface 16a of the inner ring 16 is such that the inner diameter of the inner ring 16 is maximum in the vicinity of the terminal ends 31a and 32a of the suction ports 31 and 32. In addition, the design that the inner diameter gradually decreases until reaching the start ends 33a, 34a of the discharge ports 33, 34 greatly contributes to prevention of cavitation. This cavitation may occur due to the fact that the suction of the fluid cannot catch up with the movement of the vane 14 during the period from the suction stroke to the discharge stroke, but the cam profile as shown in FIG. It is possible to make up for the shortage of the inflow of fluid by gradually decreasing the volume after the volume of the chamber is maximized, thereby enabling the cavitation to be effectively suppressed.

  On the other hand, in the vane pump according to this embodiment, the inner peripheral portions (or the whole) of the fixing members 37 and 38 are constituted by elastic bodies 37b and 38b, and the inner peripheral surfaces of these elastic bodies 37b and 38b are Since the elastic bodies 37b and 38b are elastically deformed so as to maintain the contact with the outer peripheral surface of the inner ring 16 regardless of the elastic deformation of the inner ring 16, the inner ring is also provided in the region where the fixing members 37 and 38 are disposed. The shape of 16 can be stabilized.

  The variable displacement vane pump according to the present invention is not limited to the one according to the embodiment described above. For example, the following aspects may be adopted.

  1) The side housing may have only a single suction port and a single discharge port. Also in this case, the outer movable member is disposed so as to contact the portion including the region from the end of the suction port to the start end of the discharge port of the inner ring, and the outer side so as to contact other portions. A fixing member may be provided. However, as described above, the suction port is divided into the first suction port 31 and the second suction port 32, and the discharge port is divided into the first discharge port 33 and the second discharge port 34. The drive torque can be reduced.

  2) The flattening direction of the inner ring is not limited. For example, the inner ring may be installed in such a posture that the major axis extends substantially in the left-right direction and the minor axis extends substantially in the vertical direction. In this case, the outer movable member may be disposed on the left and right sides of the inner ring, for example.

  3) The capacity operation means for moving the outer movable member is not limited to one using hydraulic pressure (discharge fluid pressure) as shown in FIG. For example, a thrust of a feed screw driven by a motor or a driving force of a solenoid device may be used.

It is a section front view showing the state where the maximum discharge capacity was specified in the variable capacity vane pump concerning an embodiment of the invention. It is a section front view showing the state where the capacity lower than the maximum discharge capacity was specified in the variable capacity type vane pump concerning the embodiment of the present invention. It is the cross-sectional front view which expanded the principal part of the said variable capacity type vane pump. It is the IV-IV sectional view taken on the line of FIG. It is a cam profile set about the inner peripheral surface shape of the inner ring of the variable displacement vane pump. It is a sectional front view showing the conventional variable capacity type vane pump.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Drive shaft 12 Rotor 12a Outer surface of rotor 14 Vane 16 Inner ring 16a Inner surface of inner ring 18 Outer holding member 20 Side housing 22 Capacity operation device 31 First suction port 31a End of first suction port 32 Second suction port 32a End of second suction port 33 First discharge port 33a Start end of first discharge port 34 Second discharge port 34a Start end of second discharge port 35 First movable member 35a Inner side surface of first movable member 36 Second movable member 36a Inner side surface of second movable member 37 First fixing member 37b Elastic body of first fixing member 38 Second fixing member 38b Elastic body of second fixing member 40A, 40B Hydraulic cylinder 50 Hydraulic circuit

Claims (4)

A variable displacement vane pump,
A rotor having a cylindrical outer peripheral surface and driven to rotate around the central axis of the outer peripheral surface;
A plurality of rotors that are arranged at intervals in the rotational circumferential direction of the rotor, project outward from the outer circumferential surface of the rotor in the rotational radial direction, and are held by the rotor so as to be relatively displaceable in the rotational radial direction. With one vane,
A plurality of pump chambers defined by the vanes between the inner peripheral surface and the outer peripheral surface of the rotor; and the inner peripheral surface. An inner ring capable of elastic deformation such that the inner ring is displaced inward in the rotational radial direction of the rotor,
An outer holding member for holding the inner ring from the outer side in the rotational radial direction of the rotor;
The pump chambers are surrounded from both sides in the rotation axis direction of the rotor, and are separated from the pump chamber located at a specific position from the side and from the suction port to the downstream side in the rotation direction of the rotor. A side housing having a discharge port opening from the side with respect to the pump chamber in position;
Capacity operation means for changing the displacement volume by elastically deforming the inner ring and displacing the inner peripheral surface thereof,
The inner circumferential surface of the inner ring has a terminal end of the suction port such that the inner diameter of the inner ring changes along the rotational circumferential direction of the rotor and the displacement volume is maximized when the inner ring is not deformed. Having a shape with the largest diameter in the vicinity,
The outer holding member is in contact with an outer surface of a part of the inner ring and includes a region from a terminal end of the suction port to a starting end of the discharge port, and in a rotational radial direction of the rotor. A movable outer movable member, and an outer fixed member fixed to be in contact with an outer surface of a portion other than a portion of the inner ring that is in contact with the outer movable member.
The capacity operating means displaces the outer movable member inward in the rotational radial direction of the rotor, and elastically displaces the portion of the inner ring in contact with the outer movable member radially inward. A variable displacement vane pump characterized in that it reduces the flatness of the inner peripheral surface and the displacement volume. The variable displacement vane pump according to claim 1,
The shape of the inner peripheral surface of the inner ring is such that the inner diameter of the inner ring is maximized near the end of the suction port and the inner diameter gradually decreases until reaching the start end of the discharge port. Variable displacement vane pump. The variable displacement vane pump according to claim 1 or 2,
At least the inner peripheral portion of the outer fixing member is formed of an elastic body that can be elastically deformed so as to maintain contact with the outer peripheral surface of the inner ring regardless of elastic deformation of the inner ring. Variable displacement vane pump. In the variable displacement vane pump according to any one of claims 1 to 3,
The side housing has a first suction port and a second suction port at positions facing each other across the rotation center axis of the rotor as the suction port, and the first suction port and the second suction port as the discharge port. Each having a first discharge port and a second discharge port at a position downstream of the second suction port;
The outer holding member, as the outer movable member, contacts an outer surface of a part of the inner ring including a region from the terminal end of the first suction port to the start end of the first discharge port. A first movable member, and a second movable member that is in contact with an outer surface of a part of the inner ring that includes a region from a terminal end of the second suction port to a starting end of the second discharge port. A variable displacement vane pump characterized by comprising:

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