JP5238482B2 - Variable displacement vane pump - Google Patents

Description

  The present invention relates to a variable displacement vane pump for an automobile.

  As a conventional variable displacement vane pump for automobiles, one disclosed in Patent Document 1 is known. The variable displacement vane pump disclosed in Patent Document 1 is housed in a rotatable manner having a substantially cylindrical outer peripheral surface that rotates around a rotation axis and a plurality of slits formed on the outer peripheral surface so as to protrude and retract. A plurality of vanes, a ring arranged so as to surround the rotating part, and an adapter ring arranged so as to surround the ring and fitted into an accommodation recess formed in the pump body are provided.

  The annular chamber formed between the outer peripheral surface of the rotating part and the inner peripheral surface of the ring is partitioned into a plurality of volume chambers by a plurality of vanes whose tips are in contact with the inner peripheral surface, and the ring is rotated. By rotating the rotating part in a state of being eccentric with respect to the shaft, the volume chamber is periodically expanded and contracted while rotating around the rotation axis, and the fluid sucked into each volume chamber is discharged. .

  Furthermore, the fluid is introduced into the pressurizing chamber formed between the adapter ring and the ring through the fluid passage formed in the pump body and the communication passage passing through the adapter ring and communicating with the fluid passage. The eccentric amount of the ring with respect to the rotating shaft is changed by the pressure of the introduced fluid, thereby changing the fluid discharge capacity (discharge amount per rotation).

At this time, the pressure in the pressurizing chamber is generated by a control valve configured as a spool valve. In Patent Document 1, the pressure on the upstream side and the pressure on the downstream side of the differential pressure generating section provided in the flow path on the discharge side are introduced into both end portions of the spool valve, and the position of the spool valve is determined according to the differential pressure. Thus, the flow path resistance in the pressure adjusting unit is changed, thereby changing the pressure in the pressurizing chamber. The pressure adjusting unit is configured to generate pressure in the pressurizing chamber by reducing the pressure on the discharge side (for example, the pressure on the upstream side or the downstream side of the differential pressure generating unit) with the flow path resistance. This pressure adjusting unit has, for example, an annular gap or a throttle as the flow path resistance, and the pressure reduction allowance for the pressure on the discharge side is changed by changing the length of the annular gap or the opening area of the throttle. It has become.
JP 2001-304139 A

  In the conventional variable displacement vane pump, the efficiency may decrease due to fluid leakage from the annular gap depending on the area of the annular gap between the outer periphery of the spool and the hole that accommodates the spool.

  Therefore, an object of the present invention is to obtain a variable displacement vane pump capable of reducing fluid leakage from a control valve portion configured as a spool valve.

In the present invention, the diameter of the pressure adjusting section of the spool valve included in the control valve unit of the variable displacement vane pump, it has less than the diameter of the pressure receiving portion, and a portion out Rise is formed in the spool of the spool valve, A pressure receiving portion having a larger diameter than the bulging portion is connected to one axial side of the spool of the spool valve.

According to the present invention, by making the diameter of the pressure adjusting portion smaller than the diameter of the pressure receiving portion, it is possible to reduce the area of the annular gap and reduce fluid leakage. Further, according to the present invention, since the pressure receiving portion and the spool are directly connected, a large thrust of the spool can be ensured .

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. Note that similar components are included in the following embodiments and modifications. Therefore, common reference numerals are given to those similar components, and redundant description is omitted.

  (First Embodiment) FIGS. 1 to 5 show a first embodiment of the present invention. Among these, FIG. 1 is a block diagram illustrating an example of a system in which the variable displacement vane pump according to the present embodiment is used, and FIG. 2 is a side view of the internal configuration of the variable displacement vane pump according to the present embodiment as viewed from the rotation axis direction. FIG. 3 (partial cross-sectional view) and FIG. 3 are side views showing the control valve part, where (a) is in operation, (b) is a state before operation, and FIG. It is a top view which shows the groove | channel which suppresses sticking, Comprising: (a) is a top view of the said bottom face which shows the groove | channel formed in the bottom face of the accommodating hole which accommodates a pressure receiving part, (b) is the groove | channel formed in the end surface of a pressure receiving part FIG. 5 is a diagram showing a cross-sectional view of the pressure regulating unit of the control valve unit in comparison with the conventional configuration, and FIG. 5A is a diagram showing the pressure regulating unit according to the present embodiment. (B) is a figure which shows the conventional pressure regulation part. In FIG. 2, some of the fluid passages and the like are schematically shown.

  As shown in FIG. 1, the variable displacement vane pump 1 according to this embodiment can be used as a hydraulic pressure supply source for a belt-driven continuously variable transmission system (belt CVT system 100). The hydraulic oil discharged from the variable displacement vane pump 1 is passed through the control valve 200 to each part of the belt CVT system 100 (primary pulley 101, secondary pulley 102, forward clutch 103, reverse brake 104, torque converter 105, lubrication / cooling. System 106).

  In the control valve 200, there are various electric, manual and hydraulic valves (shift control valve 201, secondary valve 202, secondary pressure solenoid valve 203, line pressure solenoid valve 204, pressure regulator valve 205, manual valve 206, A lockup / select switching solenoid valve 207, a clutch regulator valve 208, a select control valve 209, a lockup solenoid valve 210, a torque converter regulator valve 211, a lockup control valve 212, a select SW valve 213, and the like.

  The electric valve included in the control valve 200 is controlled by the control unit 300 for the belt CVT system 100.

  As shown in FIG. 2, the variable displacement vane pump 1 according to the present embodiment includes a pump part 2 and a control valve part 3, both of which are in the pump body 4. Is formed. The pump unit 2 is configured as a variable displacement vane pump, and the control valve unit 3 is configured as a spool valve.

  The pump unit 2 is housed in a substantially cylindrical housing recess 4a formed in the pump body 4, and includes a rotating unit 5 having a substantially columnar outer peripheral surface 5a that rotates about a rotation axis Ax, and an outer peripheral surface 5a. The plurality of vanes 6 accommodated in the plurality of slits 5b formed in the plurality of slits 5b, the ring 7 disposed so as to surround the rotating portion 5, and the accommodating recess disposed so as to surround the ring 7 And adapter ring 8 to be inserted into 4a. The adapter ring 8 is prevented from rotating in the housing recess 4a by a locking means (not shown).

  Then, a plurality of annular chambers R formed between the outer peripheral surface 5 a of the rotating part 5 and the inner peripheral surface 7 a of the ring 7 are provided by a plurality of vanes 6 whose tips are brought into sliding contact with the inner peripheral surface 7 a of the ring 7. The volume chamber V is partitioned.

  Further, in the present embodiment, by rotating the rotating unit 5 in a state where the ring 7 is arranged eccentrically on the left side of FIG. 2 with respect to the rotation axis Ax, the volume chamber V is rotated periodically around the rotation axis Ax. The fluid drawn into the respective volume chambers V is discharged.

  The rotating portion 5 is spline-coupled with the shaft 9 and rotates together with the shaft 9. The rotation axis Ax is also the rotation axis of the shaft 9. In the present embodiment, the rotation direction of the rotating unit 5 and the shaft 9 is the counterclockwise direction of FIG.

  In the present embodiment, the slits 5b are formed radially along the radial direction of the rotation axis Ax, and are formed at positions that divide the rotating portion 5 into 11 equal parts in the circumferential direction. A substantially cylindrical pressurizing chamber 5c is formed on the back side (rotation axis Ax side) of the slit 5b so that the vane 6 is pushed outward in the radial direction by the pressure of the fluid introduced therein. It is. In addition, since the centrifugal force by rotation acts on the vane 6, pressurization is not essential. Further, the vane 6 may be urged radially outward by an urging mechanism such as a spring.

  The vane 6 is configured as a substantially rectangular plate-like member, and in the present embodiment, the tip portion is formed in a curved shape corresponding to the inner peripheral surface 7 a of the ring 7.

  The ring 7 is formed in an annular shape with a constant radius, and the tip of the rotating vane 6 comes into sliding contact with the inner peripheral surface 7a.

  The outer peripheral surface 8a of the adapter ring 8 is formed in a substantially cylindrical surface shape, while the inner peripheral surface 8b is formed in a substantially flat cylindrical surface that is long and flat in the left-right direction in FIG. More specifically, the inner peripheral surface 8b has three planar opposing surfaces 8c, 8d, and 8e on the lower, left, and upper sides in FIG. 2, and has concave curved surfaces 8f, 8g, and 8h between the opposing surfaces. Is formed. As shown in FIG. 2, when the ring 7 is located on the leftmost side in the inner peripheral surface 8b, a gap is formed between the concave curved surfaces 8f and 8g and the outer peripheral surface 7b of the ring 7. These gaps become the pressurizing chamber 10.

  A semi-cylindrical groove 8i is formed on the facing surface 8c located on the lower side in FIG. 2, and a slightly shallow groove 7c is formed on the outer peripheral surface 7b of the ring 7 facing the groove 8i. The pin 11 is accommodated in the concave grooves 8i and 7c so as to be sandwiched between the concave grooves 8i and 7c. The ring 7 swings in the left-right direction in FIG. 2 inside the inner peripheral surface 8b of the adapter ring 8 with the pin 11 as a fulcrum.

  A coil spring 12 as an urging mechanism for urging the ring 7 leftward in FIG. 2 is interposed on the opposite side (right side in FIG. 2) of the pressurizing chamber 10 with respect to the rotation axis Ax. A compression reaction force opposite to the pressurization from the pressure chamber 10 is applied to the ring 7. In the present embodiment, the adapter ring 8 is formed with a through hole 8j that allows the coil spring 12 to pass therethrough, and one end (the left end in FIG. 2) of the coil spring 12 is the outer peripheral surface 7b of the ring 7. On the other hand, the other end portion (the right end portion in FIG. 2) is supported by a plug 13 that closes a through hole 4 b that communicates the housing recess 4 a formed in the pump body 4 with the outside.

  Further, a concave groove 8k having a substantially rectangular cross section is formed on the opposing surface 8e located on the opposite side (upper side in FIG. 2) of the pin 11 with respect to the rotation axis Ax, and a substantially rod-like shape is formed in the concave groove 8k. The sealing member 14 is inserted. The protruding end surface (lower side in FIG. 2) of the seal member 14 is in contact with the outer peripheral surface 7b of the ring 7, and when the ring 7 swings, the seal member 14 contacts the outer peripheral surface 7b of the ring 7. Are in sliding contact. In this embodiment, the seal member 14 and the pin 11 seal the crescent-shaped counter chamber 15 in a side view on the side where the pressurizing chamber 10 and the coil spring 12 are disposed.

  In the present embodiment, as shown in FIG. 2, the pressurizing chamber 10 and the opposing chamber 15 are connected to each other via a fluid passage 4 c formed in the pump body 4 and a communication passage 8 m formed in the adapter ring 8. A fluid is introduced from the control valve unit 3.

  In the pump unit 2 having the above configuration, the volume chamber V also rotates as the rotating unit 5 rotates. At this time, the ring chamber R is wide on the left side in FIG. 2 and narrow on the right side because the ring 7 is eccentric to the left in FIG. 2 with respect to the rotation axis Ax. Therefore, each volume chamber V is the narrowest at the right end of FIG. 2 and moves to the left end via the upper side of FIG. 2 as it rotates in the counterclockwise direction of FIG. Become wider. Furthermore, it is the widest at the left end of FIG. 2, and becomes narrower as it moves to the right end through the lower side of FIG. Therefore, in the pump unit 2 according to the present embodiment, in FIG. 2, the volume above the left-right line L including the rotation axis Ax (a straight line perpendicular to the rotation axis Ax and including the rotation axis Ax and the center C of the ring 7). The volume of the chamber V increases, and the volume of the volume chamber V decreases on the lower side. A discharge opening 4f facing the volume chamber V corresponding to a section in which the volume chamber V expands is formed on a side surface 4e of the housing recess 4a of the pump body 4 (a surface lateral to the moving direction of the vane 6). Is formed, and a suction opening 4g facing the volume chamber V is formed corresponding to a section in which the volume chamber V shrinks. Therefore, as the volume chamber V rotates, the volume periodically expands and contracts, and the suction opening 4g is opened in the suction stroke section I moving from right to left above the left and right line L in FIG. 2 including the rotation axis Ax. Then, the fluid is sucked in, and the fluid is discharged through the discharge opening 4f in the discharge stroke section O moving from the left to the right below the left and right line L.

  And in the said structure, if the pressure of the fluid of the pressurization chamber 10 becomes high, the ring 7 pushed by the pressure of the said fluid will move to the right side of FIG. As a result, the amount of eccentricity δ between the center C of the ring 7 and the rotation axis Ax becomes small, and the difference in volume between the volume chamber V when the volume chamber V is reduced and when the volume chamber V is enlarged becomes small. Discharge amount) is reduced. On the other hand, when the pressure of the fluid in the pressurizing chamber 10 decreases, the force with which the ring 7 is pressed to the right in FIG. 2 by the fluid pressure decreases, and the ring 7 is pushed back to the left by the coil spring 12 to the left. Moving. Then, the amount of eccentricity δ between the center C of the ring and the rotation axis Ax increases, and the volume difference between the volume chamber V when the volume chamber V is reduced and the volume when the volume chamber V is enlarged increases, so that the discharge capacity from the pump unit 2 increases. . Therefore, in this embodiment, the discharge capacity of the pump unit 2 can be changed by appropriately changing the pressure of the fluid introduced into the pressurizing chamber 10. In the present embodiment, fluid is also introduced into the facing chamber 15, and the pump is driven by the pressure of the fluid in the pressurizing chamber 10 and the facing chamber 15 and the biasing force (compression reaction force) of the coil spring 12 as the biasing means. The discharge capacity of the part 2 changes.

  Here, in the present embodiment, the pressure of the fluid in the pressurizing chamber 10 and the counter chamber 15 is adjusted using the control valve unit 3. The control valve portion 3 is configured as a spool valve, and in this embodiment, as shown in FIG. 3A, a cross-section accommodated in a bottomed cylindrical accommodation hole 16 formed in the pump body 4. A substantially circular rod-shaped spool 17 is provided. The spool 17 is formed with two bulging portions 17a and a constricted portion 17b between them, and the inner peripheral surface 16a of the accommodation hole 16 has a fluid corresponding to each bulging portion 17a. An opening 16b communicating with the passage 4c is formed.

  In addition, on one side in the axial direction of the spool 17 (right side in FIG. 3A in the present embodiment), a pressure receiving part 24 having a substantially disc shape and concentric with the bulging part 17a is connected. . The pressure receiving portion 24 is accommodated in a bottomed cylindrical accommodation hole 25 that is concentric with the accommodation hole 16 and has a larger diameter than that. The difference in diameter of the annular gap between the outer periphery of the pressure receiving portion 24 and the inner peripheral surface of the accommodation hole 25 is set to be relatively small.

  As shown in FIG. 2, the discharge line 18 is provided with a differential pressure generating section (for example, an orifice or a choke throttle) 19 that generates a differential pressure according to the flow rate. Then, the upstream side of the differential pressure generating portion 19 and the inner chamber 24a on the left side of FIG. 3A with respect to the pressure receiving portion 24, and the inner side of the passage 20a and the spool 17 on the left side in FIG. The chamber 3a and the passage 17d formed in the spool 17 communicate with each other, while the downstream side of the differential pressure generating portion 19 and the inner chamber 24b on the right side of FIG. It communicates via Since the pressure on the upstream side of the differential pressure generating unit 19 is higher than that on the downstream side, and the flow rate increases, the differential pressure increases. Therefore, as the flow rate of the discharge line 18 increases, the pressure in the left inner chamber 24a increases. Thus, the spool 17 receives a force toward the right side of FIG. At this time, the right end surface 24c in FIG. 3A of the pressure receiving portion 24 is pressed toward the left side in FIG. 3A by the coil spring 21 as the biasing means. Therefore, the spool 17 is positioned in the accommodation hole 16 where the differential pressure of the inner chambers 24a and 24b (that is, the differential pressure of the differential pressure generating portion 19) and the compression reaction force of the coil spring 21 are balanced. Become. In the present embodiment, the inner chamber 3a is further to the left with respect to the left bulging portion 17a in FIG. 3A, and is further to the right with respect to the right bulging portion 17a in FIG. 3A. By communicating the inner chamber 24a with the passage 17d penetrating the inside of the spool 17 in the axial direction (longitudinal direction), the fluid acting on the two bulging portions 17a and 17a from the left and right in FIG. The pressure is balanced.

  And the pressure regulation part 22 is comprised by the bulging part 17a of the spool 17, and the opening 16b formed in the internal peripheral surface 16a of the accommodation hole 16. As shown in FIG. Specifically, each opening 16b is configured to be at least partially covered by the outer peripheral surface 17c of the corresponding bulging portion 17a, and in each pressure adjusting portion 22, the opening area of the opening 16b or the opening 16b The pressure on the fluid passage 4c side changes according to the length (overlap length) at which the outer peripheral surface 17c and the inner peripheral surface 16a overlap on the high pressure side. The inner chamber 3c formed in the accommodation hole 16 by the narrowed portion 17b between the two bulging portions 17a and 17a communicates with the reservoir tank 23 through the passage 20c.

  The pressure adjusting unit 22 on the left side of FIG. 3A is for adjusting the pressure in the pressurizing chamber 10, and in this pressure adjusting unit 22, the spool 17 is positioned on the left side of FIG. The opening area of the opening 16b is reduced, or the length (overlap length) at which the outer peripheral surface 17c and the inner peripheral surface 16a face each other (overlap) between the opening 16b and the left inner chamber 3a is increased. The pressure reduction allowance for the pressure in the inner chamber 3a (≈the pressure on the upstream side of the differential pressure generator 19) increases, and the pressure in the pressurizing chamber 10 decreases. Conversely, the more the spool 17 is located on the right side of FIG. 3A, the larger the opening area of the opening 16b, or the shorter the overlap length, the smaller the pressure reduction, and the pressure in the pressurizing chamber 10 is reduced. Get higher.

  The pressure adjusting unit 22 on the right side of FIG. 3A is for adjusting the pressure in the facing chamber 15, and the pressure adjusting unit 22 opens as the spool 17 is positioned on the left side of FIG. The opening area of 16b is increased, or the length (overlap length) at which the outer peripheral surface 17c and the inner peripheral surface 16a face (overlap) between the opening 16b and the inner chamber 24a on the right side thereof is shortened. The pressure reduction allowance with respect to the pressure in the inner chamber 24a (≈the pressure on the upstream side of the differential pressure generating unit 19) is reduced, and the pressure in the facing chamber 15 is increased. Conversely, the closer the spool 17 is to the right side of FIG. 3A, the smaller the opening area of the opening 16b, or the longer the overlap length, the greater the pressure reduction, and the lower the pressure in the facing chamber 15. Become. In the present embodiment, the pressure in the pressurizing chamber 10 is made higher than the pressure in the facing chamber 15 by appropriately adjusting the positional relationship between the two bulging portions 17a.

  Therefore, in this embodiment, when the flow rate in the discharge line 18 (= discharge flow rate of the pump unit 2) increases and the differential pressure in the differential pressure generating unit 19 increases, the spool 17 moves to the right side of FIG. Then, the pressure reduction at the two pressure adjusting sections 22 changes, and the pressure in the pressurizing chamber 10 increases and the pressure in the facing chamber 15 decreases. Therefore, the ring 7 is pressed to the right side of FIG. 2 and adjusted so that the discharge amount (discharge capacity) per rotation of the pump unit 2 is reduced. Conversely, when the discharge flow rate in the discharge line 18 decreases and the differential pressure at the differential pressure generating unit 19 decreases, the spool 17 moves to the left in FIG. The margin changes, and the pressure in the pressurizing chamber 10 decreases and the pressure in the facing chamber 15 increases. Therefore, the ring 7 is pressed to the left side in FIG. 2 and adjusted so that the discharge amount (discharge capacity) per rotation of the pump unit 2 increases.

  That is, in the present embodiment, the control valve unit 3 changes the discharge capacity of the pump unit 2 by adjusting the pressure according to the flow rate of the discharge line 18 (= discharge flow rate per unit time from the pump unit 2). Thus, it is configured as a flow rate sensitive feedback control valve (constant flow rate control valve) for controlling the flow rate of the discharge line 18 (= discharge flow rate per unit time from the pump unit 2).

  That is, the variable displacement vane pump 1 according to the present embodiment can change the discharge amount (discharge capacity) per one rotation according to the rotation speed so that the discharge flow rate becomes substantially constant (or a constant width). Therefore, when the shaft 9 is rotationally driven by a drive source that changes the rotational speed of an engine or the like, the variable displacement vane pump 1 obtains a flow rate within a certain range regardless of the change in the rotational speed. This is useful when you want to reduce work waste. Specifically, it can be applied to an oil pump used in a belt CVT system or a power steering system.

  As described above, in the present embodiment, the diameter of the pressure adjusting portion 22 of the spool 17 (that is, the diameter of the outer peripheral surface 17c of the bulging portion 17a and the inner peripheral surface 16a of the accommodation hole 16) is determined from the diameter of the pressure receiving portion 24. I made it smaller. The leakage of fluid in the annular gap increases as the area of the annular gap increases, and thus the diameter (inner diameter or outer diameter) of the annular gap increases. In the present embodiment, as shown in FIG. 5A, the diameter D1 of the pressure adjusting unit 22, that is, the diameter of the annular gap in the pressure adjusting unit 22 is compared with the conventional diameter D2 shown in FIG. The leak is reduced by making it smaller. In particular, when used in the belt CVT system 100, contamination (foreign matter) having a relatively large size may enter. When the clearance (difference between the inner diameter and the outer diameter) δ1 of the annular gap is narrowed, the spool 17 is caused by the contamination. May occur. In this respect, in the present embodiment, it is possible to reduce the leak by reducing the diameter D1 while securing the clearance δ1 of the annular gap to some extent and suppressing the sticking. Furthermore, in this embodiment, the thrust of the spool 17 is ensured larger by forming the pressure receiving portion 24 larger than the pressure adjusting portion 22. Therefore, according to the present embodiment, it becomes easy to ensure the thrust of the spool 17 and reduce the leak from the control valve portion 3, thereby suppressing the fixation of the spool 17 while suppressing the decrease in pump efficiency. It is possible to obtain a variable displacement vane pump that can be used. When the variable displacement vane pump 1 having the spool valve (control valve unit 3) having such a configuration is incorporated in the belt CVT system 200, when there is less leakage, the response to the pressure change becomes faster, and an early shift request occurs. In addition, the shift control line can be quickly changed to a high pressure and high flow rate state, and the shift response speed can be improved. Further, since the fluid leakage is reduced, the pump efficiency is improved and the fuel efficiency of the vehicle can be improved.

  Further, in this embodiment, the end portion of the coil spring 21 that urges the spool 17 to one side is brought into contact with the pressure receiving portion 24. For this reason, it is easier to increase the diameter of the coil spring 21 and to ensure the thrust as compared with the case where it is brought into contact with the bulging portion 17a forming the pressure adjusting portion 22, and the stress of the coil spring 21 is further increased. Durability is easily improved by the amount that is easily lowered.

  Since the variable displacement vane pump 1 is not operating before the engine is started, no hydraulic pressure acts on the discharge line 18 as shown in FIG. 3B, and the pressure receiving portion 24 coupled to the spool 17 is The urging force of the coil spring 21 is in contact with the bottom surface 25 a of the accommodation hole 25. Here, in the present embodiment, as shown in FIG. 4A, a groove 25b communicating with the opening of the accommodation hole 16 is formed on the bottom surface 25a. A plurality of grooves 25b may be provided in a cross shape or a radial shape, or may be configured as a cutout or an inclined surface communicating with the accommodation hole 16.

  In such a configuration, when the engine is started and the variable displacement vane pump 1 starts to operate, the fluid is received from the pressure receiving portion 24 and the bottom surface 25a through the opening of the accommodation hole 16 even when the discharge flow rate of the variable displacement vane pump 1 is small. It becomes easy to make it spread to the whole pressure receiving part 24. Therefore, after the engine is started, a counter force against the urging force of the coil spring 21 can be obtained as quickly as possible, so that a good operation of the spool 17 is ensured and the CVT shift response speed is increased. be able to.

  Instead of forming the groove portion 25b on the bottom surface 25a, as shown in FIG. 4B, the groove portion 24e may be formed on the end surface 24d of the pressure receiving portion 24, or a ridge is formed instead of the groove portion. May be.

  (First Modification of First Embodiment) FIG. 6 is a sectional view of a pressure regulating section and a pressure receiving section of a control valve section of a variable displacement vane pump according to a first modification of the first embodiment of the present invention. (A) is sectional drawing of a pressure regulation part, (b) is sectional drawing of a pressure receiving part.

  As shown in FIG. 6, in this modification, the clearance δ11 of the annular gap of the pressure adjusting portion 22V is formed narrower (smaller) than the clearance δ2 of the annular gap of the pressure receiving portion 24 (δ11 <δ2).

  According to such a configuration, the radial position of the spool 17 in the accommodation hole 16 can be defined by the clearance δ11 of the annular gap of the pressure adjusting unit 22. If the radial position of the spool 17 in the accommodation hole 16 is defined by the clearance δ2 of the annular gap of the pressure receiving portion 24, the spool 17 is unidirectional in the radial direction in the accommodation hole 16 in the pressure adjusting portion 22. Therefore, there is a risk that leakage in the pressure adjusting unit 22 may increase and it may be difficult to assemble. In this regard, in this modification, it is possible to suppress the radial deviation of the spool 17 in the pressure adjusting unit 22 and to prevent these problems from occurring. Further, the amount of clearance δ11 itself is reduced, which contributes to reducing the leakage in the pressure adjusting unit 22V.

  (Second Modification of First Embodiment) FIG. 7 is a side view showing a control valve portion of a variable displacement vane pump according to a second modification of the first embodiment of the present invention.

  In the variable capacity vane pump 1V according to the present modification, the passage 17d is not formed in the spool 17, but the passage 17d having a communication function substantially equivalent to this is provided in the body of the control valve portion 3V (in this embodiment, the pump body). 4V). With this configuration, the manufacturing cost of the spool 17 can be reduced. Further, since the passage 17d is easily formed as a wider passage, the pressure loss is reduced, the response of the change in the discharge amount is easily improved, and the discharge amount can be adjusted more accurately.

  (Second Embodiment) FIG. 8 is a side view showing a control valve portion of a variable displacement vane pump according to this embodiment, and FIG. 9 is a side view showing an operation state of the control valve portion different from FIG. Note that the pump section of the variable displacement vane pump 1A according to the present embodiment can be the same as that of the first embodiment. Therefore, the description thereof is omitted below.

  In the present embodiment, the control valve unit 3A is the same as the first embodiment in that the diameter of the pressure adjusting unit 22A is smaller than the diameter of the pressure receiving unit 24A.

  However, in the present embodiment, the pressure receiving portion 24A is provided on the side opposite to the coil spring 21 as the biasing means of the spool 17A (left side in FIGS. 8 and 9), and the seat plate 26 of the coil spring 21 is It is provided separately from the part 24A.

  In such a configuration, the inner chamber 24a on the left side of FIGS. 8 and 9 with respect to the pressure receiving portion 24A communicates with the upstream side of the differential pressure generating portion 19 (FIG. 2) via the passage 20a (FIG. 2). The inner chamber 24b on the right side of FIGS. 8 and 9 with respect to the pressure receiving portion 24A is the downstream side of the differential pressure generating portion 19, the inner chamber 3b on the right side of FIGS. 8 and 9 with respect to the spool 17A, and the spool The spool 17A is pressed to the right side of FIGS. 8 and 9 as the differential pressure of the differential pressure generating portion 19 increases, and the compression reaction force of the coil spring 21 is communicated via the passage 17d in 17A. It is designed to stay in a position that balances. Therefore, the pressure adjusting action of the pressurizing chamber 10 and the counter chamber 15 by the pressure adjusting unit 22A is the same as that in the first embodiment. Therefore, the same effects as those of the first embodiment can be obtained also by the present embodiment described above.

  Further, in the present embodiment, when the discharge flow rate from the pump unit is small, that is, in the state where the flow rate at the differential pressure generating unit 19 is small, the spool 17A is positioned on the left side as shown in FIG. 3d (the left opening 3d in FIG. 9) of the fluid passage 4c communicating with the inner chamber 3c (the inner chamber formed by the narrowed portion 17b) communicating with the opening 3e of the passage 20c (FIG. 2) from the reservoir tank 23. 3c) and on the inner chamber 24b side which is the high pressure side with respect to the left pressure adjusting portion 22 in FIGS. 8 and 9, the outer peripheral surface 17c of the bulging portion 17a and the inner periphery of the accommodation hole 16 The flow path resistance at the overlap with the surface 16a is maximized to suppress the pressure in the pressurizing chamber 10 from being increased, so that the discharge capacity of the variable capacity vane pump 1A is increased. When the flow rate of the differential pressure generating portion 19 is small, the pressure fluctuation tends to increase, and the pressure in the facing chamber 15 decreases due to leakage from each portion, so that the ring 7 reduces the flow rate. If pushed, the discharge capacity may be smaller than the expected amount. In this regard, in the present embodiment, when the flow rate is low, the pressure in the pressurizing chamber 10 can be lowered to increase the discharge capacity, and the discharge flow rate of the variable capacity vane pump 1A (pump unit 2) is excessively reduced. Can be suppressed.

  (Third Embodiment) FIG. 10 is a side view showing a control valve portion of a variable displacement vane pump according to this embodiment. In addition, the pump part of the variable displacement vane pump 1B according to the present embodiment can be the same as that of the first embodiment. Therefore, the description thereof is omitted below.

  Also in this embodiment, the control valve unit 3B is the same as the first and second embodiments in that the diameter of the pressure adjusting unit 22B is smaller than the diameter of the pressure receiving unit 24B.

  However, the present embodiment is different from the first embodiment in that the portion where the pressure adjusting portion 22B of the spool 17B is formed is accommodated in the cylinder of the sleeve 27. By using the sleeve 27, it becomes easier to improve the dimensional accuracy of the accommodation hole 16, compared with the case where the accommodation hole 16 that accommodates the spool 17B is formed in the pump body 4, and it is easier to improve efficiency by further reducing leakage. Become.

  In the present embodiment, the spool 17B and the pressure receiving portion 24B are accommodated in a cylindrical accommodation hole 4i having a constant diameter formed in the pump body 4. For this reason, compared with the case where these accommodation holes are formed separately, the labor of hole processing can be reduced and manufacturing cost can be reduced.

  Furthermore, in the present embodiment, the sleeve 27 and the plug portion 28 of the accommodation hole 4i are integrated. For this reason, compared with the case where these are comprised separately, a number of parts can be reduced and manufacturing cost can be reduced.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made. For example, the configuration of the pump unit in addition to the configuration of the control valve unit is not limited to the above embodiment, and various modifications can be made.

It is a block diagram which shows an example of the system by which the variable displacement vane pump concerning embodiment of this invention is used. It is the side view (partial sectional view) which looked at the internal structure of the variable capacity vane pump concerning a 1st embodiment of the present invention from the direction of a rotation axis. It is the side view (partial sectional view) which looked at the internal structure of the control valve part of the variable capacity vane pump concerning a 1st embodiment of the present invention from the direction of a rotation axis, (a) is in operation and (b) is in operation. It is a figure which shows the previous state. It is a top view which shows the groove | channel which suppresses sticking of the pressure receiving part of the variable capacity vane pump concerning 1st Embodiment of this invention, Comprising: (a) is the said which shows the groove | channel formed in the bottom face of the accommodation hole which accommodates a pressure receiving part The top view of a bottom face, (b) is a top view of the said end surface which shows the groove | channel formed in the end surface of a pressure receiving part. It is a figure showing a sectional view of a pressure regulation part of a control valve part of a variable capacity vane pump concerning a 1st embodiment of the present invention compared with the conventional composition, and (a) shows a pressure regulation part concerning a 1st embodiment. The figure which shows, (b) is a figure which shows the conventional pressure regulation part. It is sectional drawing of the pressure regulation part and pressure receiving part of the control valve part of the variable displacement vane pump concerning the 1st modification of 1st Embodiment of this invention, (a) is sectional drawing of a pressure regulation part, (b) is It is sectional drawing of a pressure receiving part. It is a side view which shows the control valve part of the variable displacement vane pump concerning the 2nd modification of 1st Embodiment of this invention. It is the side view which looked at the internal structure of the control valve part of the variable capacity vane pump concerning 2nd Embodiment of this invention from the rotating shaft direction (partial sectional drawing). It is the side view (partial sectional view) which looked at the internal structure of the control valve part of the variable capacity vane pump concerning a 2nd embodiment of the present invention from the direction of a rotation axis, and is a figure showing the state where the discharge flow rate is small. It is the side view (partial cross section figure) which looked at the internal structure of the control valve part of the variable capacity vane pump concerning 3rd Embodiment of this invention from the rotating shaft direction.

Explanation of symbols

1, 1A, 1B, 1V Variable displacement vane pump 2 Pump part 3, 3A, 3B, 3V Control valve part 17, 17A, 17B, 17V Spool 19 Differential pressure generating part 21 Coil spring 22, 22A, 22B, 22V Pressure regulating part 24 , 24A, 24B Pressure receiving part

Claims (4)

A pump unit configured as a vane pump capable of changing the discharge capacity, a pressure receiving unit that receives a differential pressure before and after a differential pressure generating unit provided in the discharge side flow path, and a pressure on the discharge side flow path to reduce the pressure In a variable capacity vane pump comprising a control valve portion configured as a spool valve having a pressure regulating portion that generates a control pressure for changing the discharge capacity of the portion,
Wherein the spool of the spool valve part out Rise is formed, the large-diameter pressure bearing portion than the swollen portion in the axial direction one direction side of the spool of the spool valve is connected,
A variable displacement vane pump characterized in that a diameter of the pressure adjusting portion is smaller than a diameter of the pressure receiving portion.   The variable capacity vane pump according to claim 1, wherein a clearance of the annular gap of the pressure adjusting unit is narrower than a clearance of the annular gap of the pressure receiving unit. A pump unit configured as a vane pump capable of changing the discharge capacity, a pressure receiving unit that receives a differential pressure before and after a differential pressure generating unit provided in the discharge side flow path, and a pressure on the discharge side flow path to reduce the pressure In a variable capacity vane pump comprising a control valve portion configured as a spool valve having a pressure regulating portion that generates a control pressure for changing the discharge capacity of the portion ,
A variable displacement vane pump characterized in that a diameter of the pressure adjusting portion is smaller than a diameter of the pressure receiving portion, and a clearance of the annular gap of the pressure adjusting portion is narrower than a clearance of the annular gap of the pressure receiving portion. A coil spring biasing the spool of the spool valve on one side, varying according to the end portion of the coil spring to claim 1, 2 or 3, characterized in that so as to abut against the pressure receiving portion Capacity vane pump.

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