JP2005120893A - Vane pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vane pump, heightening the rigidity of a rotor without lowering the rigidity of a vane guide. <P>SOLUTION: This vane pump includes: side plates 13 disposed with a cam ring and a rotor held between them in the axial direction and having an inside surface where a vane is brought into sliding contact; and a vane guide 60 having a contact surface 60a1 for setting the position of the vane inward in the radial direction by contact of the vane. The vane guide 60 has a fit-in part fitted in a storing recessed part 61 formed in the inside surface 13f of the side plate 13, and the storing recessed part 61 is larger than the outline of the contact surface 60a1 seen in the axial direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vane pump in which a plurality of vanes forming a plurality of pump chambers between a cam member and a rotor are provided in a rotor so as to be slidable in a radial direction. Used as a hydraulic pump for supplying to a step transmission.

In the vane pump, a vane guide is provided for pushing the vane radially outward as the rotor rotates. For example, in the vane pump disclosed in Patent Document 1, a one-side lid and an other-side lid that cover the main body and the rotor from both sides are provided, and a guide plate (corresponding to a vane guide) is attached to the other-side lid. In addition, oil discharged from the pump chamber is formed on the one-side lid body in order to cause the back pressure to push the vane radially outward to act on the vane at the base end portion of the vane groove into which the vane is inserted. It is supplied through a supply path for back pressure.
Japanese Patent Laid-Open No. 10-306783

  By the way, in order to increase the rigidity of the rotor, it is preferable that the vane guide is thin. On the other hand, if the thickness is too thin, the rigidity of the vane guide is lowered. Also, in the suction area where the volume of the pump chamber increases, the back pressure decreases due to the vanes moving radially outward, so the back pressure supply path is designed to increase the back pressure of the vanes in the suction area. May be provided only at a position corresponding to. On the other hand, in the discharge area where the volume of the pump chamber is reduced, the back pressure rises due to the vanes moving inward in the radial direction. Therefore, when the back pressure supply path is provided in the discharge area, the sliding resistance of the vanes increases. . Therefore, it is preferable to increase the back pressure from the starting point of the suction area. However, for this purpose, it is necessary to increase the processing accuracy of the back pressure supply path, which increases the cost.

  The present invention has been made in view of such circumstances, and the invention according to claim 1-4 provides a vane pump capable of increasing the rigidity of the rotor without reducing the rigidity of the vane guide. With the goal. Furthermore, the inventions described in claims 2 and 3 are intended to provide a vane pump that does not require an increase in processing accuracy and can increase the back pressure of the vane from the starting point of the suction area at a low cost. The fourth aspect of the present invention aims to increase the degree of freedom of the formation positions of the first and second portions constituting the back pressure supply path.

  The invention according to claim 1 is a vane pump including a housing and a pump unit accommodated in the housing, wherein the pump unit includes a cam member having a cam surface formed on an inner peripheral surface, and the cam member. And a plurality of vanes that are slidably provided in the rotor in a radial direction and that are in contact with the cam surface to form a plurality of pump chambers between the cam member and the rotor. And the first and second side members that are disposed with the cam member and the rotor sandwiched in the axial direction and that have inner surfaces on which the vanes are slidably contacted, and radially inward by the contact of the vanes. And a vane guide having a contact surface for setting the position of each vane in the vane pump, wherein the vane guide is a receiving recess formed on the inner side surface of the first side member. It has a fitting portion which is fitted within the housing recess is larger vane pump than the outer shape of the contact surface when viewed from the axial direction.

  According to this, the vane guide has a thickness that can ensure the required rigidity, and the thickness of the vane guide that protrudes in the axial direction from the inner surface is reduced by the amount of the insertion portion. Can do.

  According to a second aspect of the present invention, in the vane pump according to the first aspect, a high-pressure chamber into which high-pressure hydraulic fluid discharged from the pump chamber flows between the housing and the second side member in the axial direction. A back pressure chamber is formed in the rotor, and back pressure working fluid is introduced into the bottom of the vane groove into which the vane is inserted. The side member is formed with first and second back pressure supply passages for supplying back pressure hydraulic fluid to the back pressure portion, respectively, and the second back pressure supply passage communicates with the high pressure chamber and enters the suction area. A hydraulic fluid for back pressure is supplied to the vane, and the first back pressure supply passage communicates with the high pressure chamber through the second back pressure supply passage and the back pressure chamber, and from the discharge area to the suction area. Supplying back pressure hydraulic fluid to the vanes in the transition zone A.

  According to this, the back pressure hydraulic fluid is supplied to the vane at the starting point of the suction area through the first back pressure supply path. The pressure of the hydraulic fluid in the first back pressure supply path is the pressure of the hydraulic fluid supplied from the high pressure chamber through the second back pressure supply path and the back pressure chamber. Since the hydraulic fluid pressure in the discharge area is lower than the hydraulic fluid pressure in the second back pressure supply path by the amount of hydraulic fluid leakage from the gap, the back pressure of the vane in the discharge area is supplied from the second back pressure supply path to the back pressure chamber. It is small compared to the pressure of hydraulic fluid.

  According to a third aspect of the present invention, in the vane pump according to the second aspect, the first back pressure supply path is formed by a groove formed in a bottom wall of the housing recess, and the first back pressure supply path is the vane. The back pressure working fluid is supplied to the back pressure chamber from an opening formed by being not covered by the guide.

  According to this, since the openings 63a and 63b communicating with the back pressure chamber are formed by using the vane guide and the groove is formed in the bottom wall of the housing recess, the first back is formed by the amount of the housing recess. Since the volume of the pressure supply path is increased, the pressure drop of the back pressure hydraulic fluid in the first back pressure supply path due to leakage from a minute gap of the pump unit is suppressed.

  According to a fourth aspect of the present invention, in the vane pump according to the second aspect, the vane guide is fixed to the first side member by a pair of pins, and the first back pressure supply path is formed by an annular groove, The first back pressure supply path is divided into two parts by the pair of pins, the first and second parts formed over the suction area and the discharge area, respectively. The flow of the hydraulic fluid for back pressure is blocked or restricted by the pair of pins.

  According to this, since the back pressure supply path is bisected by using the pin for fixing the vane guide to the side member, the first and second portions are formed by changing the position of the pin. The position can be changed easily.

  According to invention of Claim 1, the following effect is show | played. In other words, the thickness of the vane guide has sufficient thickness to ensure the required rigidity, and the thickness of the vane guide protruding in the axial direction from the inner surface can be reduced, so that the rigidity of the rotor can be reduced without reducing the rigidity of the vane guide. An enhanced vane pump is obtained.

  According to invention of Claim 2, in addition to the effect of the invention of the cited claim, there exists the following effect. That is, since the back pressure hydraulic fluid is supplied to the vane at the starting point of the suction area through the first back pressure supply path, it is not necessary to increase the processing accuracy of the second back pressure supply path, and suction is performed at low cost. The back pressure of the vane can be increased from the starting point of the region, and the discharge efficiency is improved.

  According to invention of Claim 3, in addition to the effect of the invention of the cited claim, there exist the following effects. That is, the opening of the first back pressure supply passage can be easily formed, and the pressure drop of the back pressure working fluid in the first back pressure supply passage is suppressed. Can be increased.

  According to invention of Claim 4, in addition to the effect of the invention of the cited claim, there exists the following effect. That is, since the position to be divided into two can be easily changed by changing the position of the pin, the degree of freedom of the formation position in the circumferential direction of the first and second portions is increased.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
Referring to FIGS. 1 and 2, a vane pump P to which the present invention is applied is a hydraulic pump for supplying hydraulic oil as hydraulic fluid to a metal belt type continuously variable transmission for a vehicle, which is a hydraulic equipment. Used and placed in a transmission case in which the continuously variable transmission is accommodated.

  The vane pump P includes a pump unit U, a housing H composed of a body 1 as a first housing part and a cover 2 as a second housing part, and a body 1 and a cover 2. 1 and a cover 2 which is integrally coupled with the cover 2 (see also FIG. 11). The cover 2 is formed with a recess 2b that opens in a mating surface 2a with the seal plate 3, and the recess 2b is covered with the seal plate 3, thereby forming a storage chamber 4 in which the pump unit U is stored.

  The drive shaft 5 of the vane pump P that is rotationally driven in the rotation direction R by the internal combustion engine mounted on the vehicle is provided with a mounting portion 5a to which a power transmission member for transmitting the power of the crankshaft of the internal combustion engine is mounted. On the part side, it is rotatably supported by the housing H via a bearing 6 attached to the body 1 and a bearing 7 attached to the bottom wall 2c of the storage chamber 4 on the tip end side of the drive shaft 5.

  The pump unit U will be described with reference to FIG. The pump unit U includes a cam ring 10 as an annular cam member having an outer peripheral surface 10a formed of a cylindrical surface and an inner peripheral surface 10b having a shape approximate to an ellipse, a rotor 11 disposed inside the cam ring 10, and a rotor 11 A plurality of vanes 12 slidably fitted in a plurality of vane grooves 11a provided in the circumferential direction at equal intervals in the radial direction, and shafts of the cam ring 10 and the rotor 11 A first side plate 13 as a first side member that is disposed on one side in the direction A and covers one side (body 1 side) of the cam ring 10 and the rotor 11, and the cam ring 10 and the rotor 11 A second side plate 14 as a second side member disposed on the other side in the axial direction A and covering the side surface of the cam ring 10 and the other side (cover 2 side) of the rotor 11; Annular vane fixed to side plate 13 Comprises a de 60, and a positioning pin 15 of the pair. Both pins 15 pass through a pair of through-holes 10c provided in the cam ring 10 in the diametrical direction in the axial direction A, and a pair of through-holes 13c provided in the first side plate 13 (FIG. 4). And a pair of recesses 14c (see also FIG. 6) provided in the second side plate 14, respectively, so that the rotor 11 and the vane 12 are disposed inside the cam ring 10, and the cam ring 10 is In a state of being sandwiched between the second side plates 13 and 14, the circumferential positions of the cam ring 10 and the side plates 13 and 14 are aligned.

  The pump unit U in which the cam ring 10, the rotor 11, the vane 12, and both side plates 13 and 14 are integrated by both pins 15 is attached to the drive shaft 5 in a state of being rotatably held by the body 1. The protrusions 15a from the first side plate 13 of both pins 15 are inserted into the pair of through holes 3c of the seal plate 5 and then press-fitted into the pair of press-fitting holes 1c of the body 3. , Fixed to the body 1. Thereafter, the cover 2 is put on the body 1 and fastened by the bolt B so that the second side plate 14 and the cover 2 are sealed by the O-ring 16.

  In this specification and claims, the axial direction A is the direction in which the rotation center line L of the rotor 11 extends, and the side is one side or the other side in the axial direction A. The radial direction and the circumferential direction mean a radial direction around the rotation center line L of the rotor 11 and a circumferential direction around the rotation center line L of the rotor 11, respectively.

  The drive shaft 5 and the rotor 11 are integrally rotated by a spline connection of the coupling portion 5b of the drive shaft 5 inserted through the insertion hole 11b formed in the central portion of the rotor 11 with the rotor 11 in the insertion hole 11b. Combined as possible. The outer ends of the vanes 12 are in sliding contact with the cam surface 17 formed on the inner peripheral surface 10b of the cam ring 10, and the first and second side plates 13 are interposed between the cam surface 17 and the outer peripheral surface of the rotor 11. , 14 is partitioned by a plurality of vanes 12, thereby forming a plurality of pump chambers 18 composed of variable volume chambers whose volumes change according to the rotation of the rotor 11.

  Further, the rotor 11 is formed with a back pressure chamber 11d that constitutes the bottom of each vane groove 11a, and between the bottom wall 2c that is a part of the cover 2 and the second side plate 14, from the pump chamber 18 A high pressure chamber 70 (see FIG. 2) is formed in which part of the discharged hydraulic oil is introduced through the second back pressure supply passages 71 and 72 formed in the second side plate 14. After the operation of the vane pump P, the hydraulic oil in the high pressure chamber 70 is guided to the back pressure chamber 11d as the back pressure hydraulic fluid through the second back pressure supply passages 71 and 72. By acting on the back surface 12e which is the end surface of the inner end of the vane 12, each vane 12 is pushed outward in the radial direction in the vane groove 11a, and the outer end of each vane 12 is pressed against the cam surface 17.

Referring to FIGS. 2 and 3, the hydraulic oil from the suction passage 24 is guided to the pump chamber 18 in a predetermined range in the circumferential direction at a position opposed to the cam ring 10 in the radial direction across the rotation center line L. A pair of first and second auxiliary suction ports 20 ₁ , 20 ₂ and a pair of first and second discharge communication passages 21 ₁ , 21 ₂ are formed. Each auxiliary suction port 20 ₁ , 20 ₂ opens at the outer peripheral surface 10 a and the cam surface 17 and is provided on both side surfaces of the cam ring 10, and each discharge communication passage 21 ₁ , 21 ₂ opens only at the cam surface 17. And a pair of recesses 21a provided on both side surfaces of the cam ring 10 and a pair of through holes 21b communicating the both recesses 21a.

  Here, the suction passage 24 includes an inlet port 24a and an annular passage 24b communicating with the suction port 24a. The suction port 24a is formed by penetrating the cover 2 in the axial direction A, and is formed by covering the hole opened at the mating surface 2a with the seal plate 3. The substantially annular annular passage 24b A gap formed between the circumferential wall surface to be formed and the outer circumferential surface of the pump unit U in the radial direction is formed by being covered with the seal plate 3.

4 to 6, the drive shaft 5 is inserted in the center of the first side plate 13 having an inner side surface 13f on the side of the pump chamber 18 on which the rotor 11 and the vanes 12 are in sliding contact. 13d and the first and second suction ports that are formed in the radial direction at positions overlapping with the first and second auxiliary suction ports 20 ₁ and 20 ₂ when viewed in the axial direction A and communicate with the pump chamber 18. 22 ₁ , 22 _2, and first and second discharge ports 23, which have through holes at positions overlapping with the first and second discharge communication passages 21 ₁ , 21 ₂ , respectively, when viewed in the axial direction A and communicate with the pump chamber 18. ₁ and 23 ₂ are formed.

  Further, the inner side surface 13f is constituted by an accommodation recess 61 in which a part of the vane guide 60 is fitted and accommodated, and an annular groove formed in the bottom surface 61a of the accommodation recess 61, in this embodiment, an annular groove. A first back pressure supply path 62 is formed as an auxiliary back pressure supply path. The first side plate 13 is formed with a mounting hole 13e which is located in the first back pressure supply path 62 and is a through hole into which a pin 64 described later is press-fitted.

  The vane guide 60 made of a flat metal plate material has an insertion hole 60d through which the drive shaft 5 is inserted in the center and a pair of pins 64 for fixing the vane guide 60 to the first side plate 13. A pair of through-holes 60e to be press-fitted is formed. Out of the outer peripheral surface 60a of the vane guide 60, the vane guide 60 is fixed to the first side plate 13 and protrudes from the housing recess 61 in the axial direction A in the axial direction A from the inner side surface 13f to the pump chamber 18 by a predetermined protrusion amount T. The portion to be configured constitutes a contact surface 60a1 with which the back surface 12e that is a part of each vane 12 contacts. Thereby, when the rotor 11 stops, the outer end of each vane 12 occupies a position facing the cam surface 17 through a slight gap or a position where the cam surface 17 is extremely lightly touched. The position of each vane 12 in the radial direction is set.

  Referring to FIG. 4, the housing recess 61 is larger than the outer shape of the contact surface 60a1 and the outer peripheral surface 60a on which the contact surface 60a1 is formed when viewed from the axial direction A. Therefore, a part of the vane guide 60 is a fitting portion 60b (see FIG. 6) that is fitted and accommodated in the accommodating recess 61. The thickness of the vane guide 60 is set so that the required rigidity for supporting each vane 12 is ensured, while the depth of the receiving recess 61 is set so that the vane guide 60 is located on the bottom surface 61a of the receiving recess 61. The protrusion amount T of the vane guide 60 is set to be as small as possible in a state where the vane guide 60 is fixed in contact with the first side plate 13.

  Referring to FIGS. 3 and 4, the first back pressure supply path 62 is divided into two parts by a pair of pins 64 into first and second portions 62 a and 62 b. The first and second portions 62a and 62b are formed over a suction area where the volume of the pump chamber 18 increases as the rotor 11 rotates and a discharge area where the volume of the pump chamber 18 decreases as the rotor 11 rotates. . Each pin 64 is disposed so as to close the first back pressure supply passage 62 at the end of the suction area, and the flow of the back pressure working fluid in the first and second portions 62a and 62b is blocked by the pin 64. Is done.

  In the first back pressure supply path 62, in each of the first and second portions 62a and 62b, portions corresponding to the latter half of the suction area and the first half of the discharge area are covered by the vane guide 60, and the suction area starts from the latter half of the discharge area. Corresponding portions are not partially covered by the vane guide 60 over the first half. The portions of the first and second portions 62a and 62b that are not covered by the vane guide 60 constitute a pair of openings 63a and 63b of the first back pressure supply passage 62. The first back pressure supply path 62 is connected to the high pressure chamber 70 through the openings 63a and 63b via the second back pressure supply paths 71 and 72 (indicated by a two-dot chain line in FIG. 3) and the back pressure chamber 11d. The back pressure hydraulic fluid is supplied to the back pressure chamber 11d corresponding to the vane 12 in the transition area from the discharge area to the suction area.

  Referring to FIGS. 3 and 10, the side surface on the pump chamber 18 side, the inner side surface 14 f in which the rotor 11 and the vane 12 are in sliding contact, and the outer side surface 14 g on the high pressure chamber 70 (see FIG. 2) side are shown. The second side plate 14 has an insertion hole 14d through which the drive shaft 5 (see FIG. 2) is inserted in the center thereof, and the high pressure chamber 70 communicates with the high pressure chamber 70 and the back pressure chamber 11d operates in the high pressure chamber 70. A pair of second back pressure supply passages 71 and 72 are formed as main back pressure supply passages for supplying oil. In this embodiment, each of the second back pressure supply passages 71 and 72 is constituted by an arc-shaped long hole that penetrates the second side plate 14 in the axial direction A, and is in the suction area as shown in FIG. In order to supply the back pressure working fluid to the back pressure chamber 11d of the vane, it is formed at a position corresponding to the suction area. In each of the second back pressure supply paths 71, 72, the radial width of the outlets 71b, 72b formed on the inner surface 14f is larger than the radial width of the inlets 71a, 72a formed on the outer surface 14g. It is set approximately equal to the radial width of the pressure chamber 11d.

Referring to FIGS. 3, 7, and 8, the inner side surface 14 f is formed with a recess opening on the outer peripheral surface at a position overlapping with the first and second suction ports 22 ₁ and 22 _{2 when} viewed in the axial direction A. In addition, first and second suction recesses 73 ₁ and 73 ₂ facing the first and second auxiliary suction ports 20 ₁ and 20 _2, and first and second discharge ports 23 ₁ and 23 _{2 when} viewed in the axial direction A And first and second discharge recesses 74 ₁ and 74 ₂ that are formed of recesses and face the first and second discharge communication passages 21 ₁ and 21 ₂ , respectively. Here, as clearly shown in FIG. 3, the pump unit U, the portion suction and discharge are carried out of the hydraulic fluid through the first suction port 22 ₁ and the first discharge port 23 ₁ constitutes a first pump section, portion suction and discharge are carried out of the hydraulic fluid through the second intake port 22 ₂ and the second discharge port 23 ₂ constitute a second pump section. In FIG. 3, the first discharge port 23 ₁ , the first discharge communication path 21 ₁ , the first discharge recess 74 ₁ , and the second discharge port 23 ₂ , the second discharge communication path 21 _2, and the second discharge use recess 74 _2, has the contour that overlaps in the axial direction a, for convenience of explanation, they are described by slightly shifting.

Then, 7, 8, as shown in FIG. 10, the first ejection recess 74 _1, a through hole penetrating projections 80 to be described later so as to communicate with the high pressure chamber 70 in the axial direction A A communication passage 75 is formed, and high-pressure hydraulic oil discharged from the pump chamber 18 of the first pump unit through the communication passage 75 is supplied to the high-pressure chamber 70 (see FIG. 2).

Figure 7, referring to FIG. 10, in the second discharge recesses 74 _2, the rearward region in the direction of rotation R is restricting portion 76 for restricting the vane 12 moves in the axial direction A are formed. Restricting portion 76 having a restricting surface 76a located on the inner surface 14f and the same plane, the virtual discharge port 77 (FIG. 7 two points in the second ejection recess 74 ₂ corresponding with the second discharge port 23 ₂ in the axial direction A It is located forward in the rotational direction R with respect to the last edge 77a. Further, restricting portion 76 is positioned in a range overlapping the pump chamber 18 as viewed in the axial direction A with (see Fig. 3), forward in the rotating direction R from the end edge 74 _{2 a} of the second discharge recesses 74 ₂ Project partially. As a result, restricting portion 76, partially projecting innermost rim 74 ₂ b of the second ejection recess 74 ₂ and the virtual discharge port 77, from 77b in a radial direction.

  Referring to FIGS. 8 to 10, the outer side surface 14 g of the second side plate 14 has an annular ridge extending over the entire circumference, in this embodiment, an annular ridge 80, and radially inward of the ridge 80. A central concave portion 81 reaching the insertion hole 14d and an annular concave portion 82 in which the O-ring 16 (see FIG. 2) is mounted are formed radially outward of the ridge 80.

The ridge 80 is formed at a position overlapping the first and second suction recesses 73 ₁ and 73 ₂ and the first and second discharge recesses 74 ₁ and 74 ₂ when viewed in the axial direction A. Thus, the ridge 80 extends circumferentially for more than the first suction recess 73 _1, 73 ₂ of the circumferential width. A boundary 83 between the ridge 80 and the central recess 81 is the innermost of the first and second suction recesses 73 ₁ and 73 ₂ and the first and second discharge recesses 74 ₁ and 74 _{2 when} viewed in the axial direction A. The peripheral edges 73 ₁ b, 73 ₂ b, 74 ₁ b, 74 ₂ b coincide with or substantially coincide with each other, and the radial width W of the ridges 80 is uniform over the entire circumference. The concave portions 74 ₁ and 74 ₂ substantially coincide with the width in the radial direction. However, the width W of the ridges 80, first, may be larger than the other portions at the portion corresponding to the ₂ second suction recess 73 _1, 73, also the height, first, second suction The portions corresponding to the concave portions 73 ₁ and 73 ₂ may be made higher than the other portions.

  Second back pressure supply passages 71 and 72 are formed in the bottom wall 81 a of the central recess 81. In addition, the thickness of the bottom wall 81a in the axial direction A is small and the depth of the central recess 81 is within the range in which the required rigidity of the second side plate 14 is ensured from the viewpoint of reducing the weight of the second side plate 14. The diameter of the peripheral wall 81b is preferably set large.

Next, the oil passages formed in the housing H and the seal plate 3 will be mainly described.
Referring to FIGS. 11 and 12, the suction passage 24 communicates with a reservoir 41 (see FIG. 12) in which hydraulic oil is stored via an oil pipe. The first and second discharge passages 25 and 26 formed in the body 1 and communicating with the pump unit U include an inlet portion 25a, an intermediate portion 25c formed by covering the groove with the seal plate 3, and an outlet portion 25b. It consists of. Inlet portion 25a, as viewed in the axial direction A, at a position overlapping with the first discharge port 23 ₁ and the first discharge communication port 3a formed respectively on first side plate 13 and the sealing plate 3. Further, the outlet portion 25b communicates with the continuously variable transmission.

A second discharge passage 26 formed by a hole (see also FIG. 2) formed in the body 1 opens from the outer peripheral surface of the body 1 to the peripheral wall surface of a valve hole 32 into which a spool 31 described later is slidably fitted. It extends in a straight line. Inlet 26a of the second discharge passage 26, as viewed in the axial direction A, at a position overlapping the second discharge port 23 ₂ and the second discharge communication port 3b formed respectively on first side plate 13 and the seal plate 3 is there.

Further, the body 1, the second discharge port 23 ₂ and the second discharge passage 26, a spool valve as a flow path switching valve for switching the first discharge passage 25 or intake passage 24 in accordance with the pump speed of the vane pump P 30 Is provided. Spool valve 30, to the second discharge port 23 ₂ and the first discharge passage 25, by performing communication and cutoff of the second discharge port 23 _2, wherein the hydraulic fluid Mu discharged from the first discharge passage 25 Controls the supply flow rate to the step transmission.

  The spool valve 30 includes a spool 31, a valve hole 32 formed in the body 1, first and second control ports 33 and 34, first and second outlet ports 35 and 36, and a return spring 37. Prepare. The spool 31 includes first and second lands 31a and 31b and a groove 31c. The distal end portion 31 a of the spool 31 receives the hydraulic pressure of the first pilot oil from the first control port 33, and the base end portion 31 b receives the hydraulic pressure of the second pilot oil from the second control port 34. The hydraulic pressures of the first and second pilot oils are controlled according to the number of revolutions of the pump by a hydraulic control valve that is controlled by a control device (not shown).

  Specifically, as shown in FIGS. 11 and 12 (A), when the pump rotation speed is equal to or lower than a predetermined value in the low rotation range, the first pilot oil is low and the second pilot oil is high. The spool 31 is connected to the communication path 31c and the first outflow port 35 by the elastic force of the return spring 37 and the hydraulic pressure of the second pilot oil, and the second outflow port 36 is connected to the second land. Occupies the first position closed by 31b.

  Further, as shown in FIG. 12B, when the pump rotation speed exceeds the predetermined value, the first pilot oil is set to a high hydraulic pressure, the second pilot oil is set to a low hydraulic pressure, and the spool 31 is returned. 11 moves to the right in FIG. 11 against the resilient force of the spring 37 to connect the communication path 31c and the second outflow port 36, and the first outflow port 35 is closed by the first land 31a. Occupies two positions. In the first position, the spool 31 communicates the second discharge path 26 with the contacted first discharge path 25 and blocks it from the suction path 22. At the second position, the spool 31 connects the second discharge path 26 with the suction path 22. And the oil passage through which the hydraulic oil flows in the second discharge passage 26 is switched so as to be disconnected from the first discharge passage 25.

  Referring to FIG. 11, a relief passage 50 branched from the connecting passage 31 c is formed across the body 1, the seal plate 3, and the cover 2, and a relief valve 51 is provided in the relief passage 50. The relief passage 50 includes an oil passage 50 a formed in the body 1, a communication port 50 b formed in the seal plate 3, and an oil passage 50 c formed in the cover 2. In the cover 2, a relief valve 51 is provided in the oil passage 50c so that the hydraulic oil in the communication passage 31c acts on the pressure receiving surface. In FIG. 4, the suction path 24 and the relief valve 51 provided in the cover 2 are indicated by a two-dot chain line. When the hydraulic pressure exceeding the allowable hydraulic pressure is generated in the communication path 31c and the second discharge path 26, the relief valve 51 causes the hydraulic oil in the relief path 50 to act on the pressure receiving surface of the valve body 52, thereby The relief valve 51 is opened against the force, and the hydraulic oil in the second discharge path 26 and the communication path 31c is discharged to the first discharge path 25.

Next, operations and effects of the embodiment configured as described above will be described.
The internal combustion engine is operated, the drive shaft 5 is driven to rotate, the rotor 11 rotates, and the volume of each pump chamber 18 increases or decreases according to the rotational position of the rotor 11. When the pump speed is equal to or less than a predetermined value in the low speed range, the spool 31 occupies the first position as shown in FIG. In this state, the hydraulic oil from the reservoir 41 passes through the suction passage 24 and passes through the first and second suction ports 22 ₁ and 22 ₂ , the first and second auxiliary suction ports 20 ₁ and 20 _2, and the first and _second ports. The air is sucked into the pump chambers 18 of the first and second pump portions in the suction area from the suction recesses 73 ₁ and 73 ₂ . The hydraulic fluid discharged in a high pressure state from the pump chambers 18 of the first and second pump sections that have shifted to the discharge zone is directly and firstly supplied to the first and second discharge ports 23 ₁ and 23 ₂ . , The second discharge recesses 74 ₁ and 74 ₂ and the first and second discharge communication passages 21 ₁ and 21 ₂ , respectively, are discharged to the first and second discharge passages 25 and 26. The hydraulic oil discharged to the second discharge path 26 reaches the inlet 25a of the first discharge path 25 via the communication path 31c of the spool valve 30 and the first outflow port 35, and the hydraulic oil of the first discharge path 25 To join. For this reason, the continuously variable transmission is supplied with hydraulic oil having a total flow rate of the hydraulic oil in the first discharge path 25 and the hydraulic oil in the second discharge path 26. Therefore, even when the pump speed is low, that is, the engine speed of the internal combustion engine is low, a flow rate that forms a sufficient oil pressure can be obtained.

  When the pump rotation speed exceeds the predetermined value, the spool 31 occupies the second position as shown in FIG. Therefore, the hydraulic oil that has passed through the suction passage 24 is sucked into the pump chamber 18 in the suction area by the first and second pump parts, and then discharged in the same manner as when the pump speed is equal to or less than the predetermined value. From the pump chamber 18 that has shifted to, the gas is discharged to the first and second discharge passages 25 and 26, respectively. The hydraulic oil discharged to the first discharge passage 25 in a high pressure state is supplied to the continuously variable transmission. On the other hand, the hydraulic oil discharged to the second discharge passage 26 passes through the communication passage 3c of the spool valve 30 and the second outlet port 36, passes through the communication port 3d, and then flows into the annular passage 24b. The second pump unit sucks the pump chamber 18 in the suction area.

  The vane guide 60 has a fitting portion 60b that is fitted into a receiving recess 61 formed on the inner side surface 13f of the first side plate 13, and the receiving recess 61 is viewed from the axial direction A. Since the vane guide 60 has a thickness that can ensure the required rigidity, the vane guide 60 has a fitting portion 60b in the axial direction A from the inner side surface 13f. Since the protruding thickness portion of the vane guide 60 can be reduced, the vane pump P in which the rigidity of the rotor 11 is increased without reducing the rigidity of the vane guide 60 can be obtained.

  In the axial direction A, a high pressure chamber 70 is formed between the cover 2 and the second side plate 14, a back pressure chamber 11 d is formed in the rotor 11, and the first and second side plates 13, 14 are in the first direction. , Second back pressure supply passages 62; 71, 72 are formed, respectively, and the second back pressure supply passages 71, 72 communicate with the high pressure chamber 70 and supply back pressure hydraulic fluid to the vane 12 in the suction area. The first back pressure supply passage 62 communicates with the high pressure chamber 70 via the second back pressure supply passages 71 and 72 and the back pressure chamber 11d, and is connected to the vane 12 in the transition region from the discharge region to the suction region. Is supplied to the vane 12 at the starting point of the suction area through the first back pressure supply passage 62. The pressure of the hydraulic oil in the first back pressure supply passage 62 is the pressure of the hydraulic oil supplied from the high pressure chamber 70 via the second back pressure supply passages 71 and 72 and the back pressure chamber 11d. The back pressure of the vane 12 in the discharge area is lower than the pressure of the hydraulic fluid in the second back pressure supply passages 71 and 72 by the amount of loss and hydraulic oil leakage from the minute gap of the pump unit. Although it is smaller than the hydraulic pressure of the hydraulic fluid supplied from the back pressure supply passages 71 and 72 to the back pressure chamber 11d, the vane 12 at the starting point of the suction area is operated through the first back pressure supply passage 62. Since the liquid is supplied, it is not necessary to increase the processing accuracy of the second back pressure supply passages 71 and 72 in order to increase the back pressure acting on the vane 12 immediately from the starting point of the suction area. The back pressure of the vane 12 can be increased from the starting point, and the discharge efficiency is improved. At this time, since the pressure of the hydraulic oil in the first back pressure supply passage 62 is smaller than the pressure in the second back pressure supply passages 71 and 72, the back pressure acting on the vane 12 in the discharge region is also smaller. The sliding resistance of the vane 12 is smaller than when hydraulic fluid is supplied from the second back pressure supply passages 71 and 72 to the vane 12 in the discharge region.

  The first back pressure supply path 62 is formed by an annular groove formed in the bottom wall of the housing recess 61, and the first back pressure supply path 62 is not covered by the vane guide 60 through the openings 63a and 63b. Since the openings 63a and 63b are formed using the vane guide 60 by supplying the back pressure hydraulic fluid to the first pressure supply fluid, the openings 63a and 63b of the first back pressure supply passage 62 can be easily formed, Since the groove is formed in the bottom wall of the housing recess 61, the volume of the first back pressure supply path 62 is increased by the amount of the housing recess, and the first back pressure due to leakage from the minute gap of the pump unit U is increased. Since the pressure drop of the back pressure hydraulic fluid in the supply passage 62 is suppressed, the back pressure of the vane 12 can be stably increased in this respect as well.

  The vane guide 60 is fixed to the first side plate 13 by a pair of pins 64, and a first back pressure supply path 62 formed of an annular groove is formed by the pair of pins 64 over the suction region and the discharge region, respectively. The first and second parts 62a and 62b are divided into two parts, and the flow of the back pressure hydraulic fluid between the first part 62a and the second part 62b is blocked by a pair of pins 64, whereby the vane guide Since the first back pressure supply path 62 is divided into two parts by using the pin 64 that fixes the 60 to the first side plate 13, the first and second portions 62 a and 62 b can be changed by changing the position of the pin 64. Since the formation position can be easily changed, the degree of freedom of the formation position in the circumferential direction of the first and second portions 62a and 62b is increased.

  Further, the pair of pins 64 are located at the end points of the suction area, and the flow of back pressure hydraulic fluid between the first portion 62a and the second portion 62b is blocked by the pins 64. Due to the rotation, the hydraulic fluid for back pressure is pushed in, and the hydraulic pressure is increased as it approaches the pin 64.

On the inner side surface 14f of the second side plate 14, first and second discharge recesses 74 ₁ and 74 ₂ are formed at positions overlapping the _first and second discharge ports 23 ₁ and 23 _{2 when} viewed in the axial direction A. , the rear side of the region in the rotational direction R in the second discharge recesses 74 _2, the vane 12 is regulating portion 76 which restricts movement in the axial direction a is formed, restricting portion 76, the second ejection recess at 74 ₂ by located forward in rotational direction R than the last edge 77a of the virtual discharge port 77 corresponding with the second discharge port 23 ₂ in the axial direction a, the rotation relative to the second end edge of the discharge port 23 ₂ In front of the direction R, the vane 12 is regulated by the regulating unit 76, and the vibration of the vane 12 in the axial direction A is suppressed. first at the leading edge of the ejection recess 74 _2, it prevents the vane 12 to the second side plate 13, 14 collides or Therefore, the generation of noise caused by the vane 12 colliding with the first and second side plates 13 and 14 and the generation of scratches on the first and second side plates 13 and 14 are prevented or suppressed. Is done.

Restricting portion 76 is configured to position within a range overlapping with the pump chamber 14 as viewed in the axial direction A, are partially protruding towards the front in the direction of rotation R from the second outlet recess 74 ₂ end edges 74 _{2 a} it allows the region occupied by the regulating unit 76 in the second ejection recesses 74 _2, it is possible to keep locally in the radial direction by the regulating portion 76 provided, the hydraulic fluid discharged from the pump chamber 18 There since it is suppressed that the flow path resistance when flowing through the second discharge recesses 74 ₂ increases, lowering of the ejection efficiency is suppressed.

Hereinafter, an embodiment in which a part of the configuration of the above-described embodiment is changed will be described with respect to the changed configuration.
Each pin 64 may be provided in the first back pressure supply path 62 so as to form a throttle that restricts the flow of the back pressure hydraulic fluid between the first portion 62a and the second portion 62b. Also, ridges 80 are first, may be formed in a substantially equal extent to the second suction recess 73 _1, 73 ₂ of the circumferential width.
A groove extending in the circumferential direction may be provided in the regulation surface 76a of the regulation part 76. In this case, the flow path resistance when hydraulic oil is discharged by the groove is reduced, and the reduction in discharge efficiency is further reduced.

It is a top view which fractures | ruptures and shows the vane pump which is embodiment of this invention. It is sectional drawing in the II-II arrow of FIG. 1 and FIG. It is the III-III arrow line view of FIG. It is a top view of the inner surface side of the 1st side plate of the vane pump of FIG. It is sectional drawing in the VV arrow line of FIG. It is sectional drawing in the VI-VI arrow view of FIG. It is a top view from the inner surface side of the 2nd side plate of the vane pump of FIG. It is a top view from the outer surface side of the 2nd side plate of FIG. It is sectional drawing in the IX-IX arrow of FIG. It is sectional drawing in the XX arrow view of FIG. FIG. 3 is an XI-XI arrow view of FIG. 2 in a state where a first side plate is placed. It is a schematic diagram explaining the flow of the hydraulic oil of the vane pump of FIG. 1, (A) is a figure when the hydraulic oil from a 2nd discharge port merges with the hydraulic oil from a 1st discharge port, (B ) Is a view when the hydraulic oil from the second discharge port returns to the suction path.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Cover, 3 ... Seal plate, 3d ... Communication port, 4 ... Housing chamber, 5 ... Drive shaft, 6, 7 ... Bearing, 10 ... Cam ring, 11 ... Rotor, 11d ... Back pressure chamber, 12 ... vane, 13, 14 ... side plate, 13f, 14f ... inner surface, 14 g ... outer surface, 15 ... pin, 16 ... O-ring, 17 ... cam surface, 18 ... pump chamber 20 _1, 20 2 _... auxiliary inlet, 21 ₁ , 21 ₂ ... discharge communication path, 22 ₁ , 22 ₂ ... suction port, 23 ₁ , 23 ₂ ... discharge port, 25, 26 ... discharge path, 24 ... suction path, 30 ... spool valve, 31 ... spool, 31c ... Communication path, 32 ... Valve hole, 33,34 ... Control port, 35,36 ... Outlet port, 37 ... Return spring, 41 ... Reservoir, 50 ... Relief passage, 51 ... Relief valve, 52 ... Valve, 56 ... Relief spring,
60 ... Vane guide, 61a1 ... contact surface, 61 ... receiving recess, 62 ... first back pressure supply path, 62a, 62b ... first and second parts, 63a, 63b ... opening, 64 ... pin, 70 ... high pressure chamber, 71, 72 ... second back pressure supply path, 73 ₁ , 73 ₂ ... suction recess, 74 ₁ , 74 ₂ ... discharge recess, 75 ... communication path, 76 ... regulating part, 77 ... virtual discharge port, 80 ... convex Strip, 81 ... central recess, 82 ... recess, 83 ... boundary,
P: vane pump, U: pump unit, H: housing, R: rotational direction, A: axial direction, L: rotational axis, T: protrusion amount, W: width.

Claims (4)

A vane pump comprising a housing and a pump unit accommodated in the housing, wherein the pump unit includes a cam member having a cam surface formed on an inner peripheral surface, and a rotor disposed inside the cam member. A plurality of vanes that are slidably provided in the rotor in the radial direction and that contact the cam surface to form a plurality of pump chambers between the cam member and the rotor; and the cam member in the axial direction. And the first and second side members that are disposed across the rotor and have inner side surfaces that are in sliding contact with the vanes, and the positions of the vanes radially inward by the contact of the vanes. In a vane pump comprising a vane guide having a contact surface to be set,
The vane guide has a fitting portion that is fitted in a housing recess formed in the inner surface of the first side member, and the housing recess is more than the outer shape of the contact surface when viewed in the axial direction. Vane pump characterized by its large size.   A high-pressure chamber into which high-pressure hydraulic fluid discharged from the pump chamber flows is formed between the housing and the second side member in the axial direction, and the vane is inserted into the rotor. A back pressure chamber is formed at the bottom of the groove to guide back pressure working fluid that causes back pressure to act on the back surface of the vane. The back pressure working fluid is supplied to the back pressure portion in the first and second side members. First and second back pressure supply passages are formed, respectively, and the second back pressure supply passage communicates with the high pressure chamber and supplies back pressure hydraulic fluid to the vane in the suction area. The pressure supply path communicates with the high pressure chamber via the second back pressure supply path and the back pressure chamber and supplies back pressure hydraulic fluid to the vane in the transition area from the discharge area to the suction area. The vane pump according to claim 1, wherein   The first back pressure supply path is formed by a groove formed in the bottom wall of the housing recess, and the back pressure chamber is formed from an opening formed when the first back pressure supply path is not covered by the vane guide. The vane pump according to claim 2, wherein the back pressure hydraulic fluid is supplied to the vane pump. The vane guide is fixed to the first side member by a pair of pins, the first back pressure supply path is formed by an annular groove, and the first back pressure supply path is formed by the pair of pins, respectively. Is divided into the first and second parts formed across the suction area and the discharge area, and the flow of back pressure hydraulic fluid is blocked by the pair of pins between the first part and the second part. The vane pump according to claim 2, wherein the vane pump is limited.

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