CN106968946A - Vehicle hydraulic device - Google Patents

Abstract

The invention relates to a vehicle hydraulic device. The set check valve (90) makes it possible to maintain the oil pressure in the back pressure oil circuit (35, 36) in the vane pump (14) while the vane pump (14) is stopped, even when the vane pump (14) is started. The vane pump (14) can still be operated smoothly. When the oil pressure control device (12) supplied with the working fluid from the vane pump (14) has been filled with the working fluid and the oil pressure in the discharge oil passages (30, 31) communicated with the oil pressure control device (12) has risen and At the point in time when the oil pressure in the back pressure oil circuit (35, 36) is exceeded, the check valve (90) opens. Therefore, the one-way valve (90) is prevented from being repeatedly opened and closed, so that the durability of the one-way valve (90) is improved.

Description

Vehicle Hydraulics

technical field

The present invention relates to a vehicle hydraulic system having a vane pump as an oil pressure source, and more particularly to a technique for enhancing the durability of a valve that applies back pressure to a vane.

Background technique

A vane pump driven by an engine has, within a pump casing having a substantially elliptical inner peripheral cam surface, for example, a rotor fitted on a rotating shaft and a plurality of blades fitted radially into vane receiving grooves formed in the rotor. A plurality of variable volume pump chambers defined by the vanes. As the vanes rotate while being pressed against the inner peripheral surface of the pump casing, the volume of each pump chamber changes, and a discharge force is applied to the working fluid.

The force for pressing the vanes against the inner peripheral surface of the pump casing is obtained from the centrifugal force of rotation and the back pressure of the inner peripheral surface of the pump casing pressing the vanes against the rotor, and the working fluid discharged from the vane pump is used to obtain the back pressure. pressure. However, if the rotational speed of the rotor is low at the start of the vane pump, the force pressing the vanes against the inner peripheral surface of the pump casing will have a negative effect on the pump even if the centrifugal force of the rotating vanes and the back pressure generated by the working fluid discharged from the vane pump are combined. The language may be too small to start smoothly.

In order to solve this problem, Japanese Patent Application Laid-Open No. 10-196557 discloses a technique for preventing the back pressure in the vane pump from decreasing when the vane pump is stopped. Specifically, in the vane pump, a vane receiving groove provided in the rotor and a discharge oil passage that supplies working fluid discharged from the vane pump to the oil pressure control device communicate with each other through a back pressure oil passage. A check valve that opens only when the pressure on the vane pump side is equal to or higher than a predetermined value is provided on the downstream side of the connection point, ie, the side of the oil pressure control circuit that receives and consumes oil pressure supply from the vane pump. Therefore, the proposed vane pump operates smoothly even at startup.

In the vane pump of JP10-196557A, when the pressure of the working fluid discharged from the vane pump to the valve becomes equal to or higher than a predetermined value, a one-way valve provided in the discharge oil passage extending from the vane pump to the oil pressure control circuit The valve transitions from a closed state to an open state. However, when the oil pressure decreases due to the opening of the valve, the check valve closes again. Thus, since the check valve is repeatedly opened and closed, the durability of the check valve may decrease.

Contents of the invention

Having been conceived against the background of the above circumstances, the present invention provides a vehicle hydraulic system including a vane pump, in which a check valve is provided to allow the vane pump to operate smoothly even when it is started, and the check valve is improved. durability.

According to one solution of the present invention, a vehicle hydraulic device is provided, which includes a vane pump and an oil pressure control circuit, and the vehicle hydraulic device further includes a check valve. The vane pump is driven to rotate by a motor. The vane pump includes a pump casing, a plurality of vanes and a rotor. The pump casing has an inner peripheral cam surface having an oval cross-sectional shape. The plurality of vanes are disposed within the pump housing. The rotor is provided with blade receiving grooves that accommodate the plurality of blades so as to be movable in a radial direction of the rotor. The oil pressure control circuit has a back pressure oil circuit and a discharge oil circuit. The back pressure oil passage is configured to supply back pressure to the plurality of vanes within the vane receiving groove. The discharge oil passage is configured to (i) guide working fluid discharged from the vane pump, and (ii) supply the working fluid to a device other than the vehicle hydraulic device. The one-way valve is provided between the back pressure oil passage and the discharge oil passage. The check valve is configured to: (i) open when the oil pressure of the working fluid in the discharge oil passage discharged from the vane pump is higher than the oil pressure in the back pressure oil passage, and (ii) preventing the flow of the working fluid when the oil pressure of the working fluid in the discharge oil passage discharged from the vane pump is equal to or lower than the oil pressure in the back pressure oil passage flow.

According to another aspect of the present invention, a vehicle hydraulic device including a vane pump and an oil pressure control circuit is provided. The vane pump is driven to rotate by a motor. The vane pump includes a pump casing, a plurality of vanes, a rotor and a check valve. The pump casing has an inner peripheral cam surface having an oval cross-sectional shape. The plurality of vanes are disposed within the pump casing. The rotor is provided with a vane receiving groove that accommodates the plurality of vanes so as to be movable in a radial direction of the rotor. The one-way valve is configured to open to allow flow of working fluid and to close to cut off the flow of working fluid. The oil pressure control circuit has a back pressure oil circuit, a discharge oil circuit and a one-way valve. The back pressure oil passage is configured to supply back pressure to the plurality of vanes within the vane receiving groove. The discharge oil passage is configured to: (i) guide the working fluid discharged from the vane pump, and (ii) supply the working fluid to other than the vehicle hydraulic device through the discharge oil passage. external device. The one-way valve is interposed between the back pressure oil passage and the discharge oil passage. The check valve is configured to: (i) open when the oil pressure of the working fluid in the discharge oil passage discharged from the vane pump is higher than the oil pressure in the back pressure oil passage, and (ii) preventing the flow of the working fluid when the oil pressure of the working fluid in the discharge oil passage discharged from the vane pump is equal to or lower than the oil pressure in the back pressure oil passage the flow.

If this configuration is adopted, the oil pressure in the discharge oil circuit, to which the working fluid is supplied from the vane pump, has been filled with working fluid and communicated with the oil pressure control circuit has risen and exceeded the back pressure oil circuit At the time point of the oil pressure in the middle, the one-way valve opens. Thus, the one-way valve is prevented from being repeatedly opened and closed, so that the durability of the one-way valve is improved.

Description of drawings

The features, advantages and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals designate like elements, and in which:

FIG. 1 is a schematic diagram showing the configuration of a main part of a vehicle hydraulic system of a first embodiment of the present invention.

Figure 2 is a front view of the vane pump of the vehicle hydraulic system of Figure 1 with its cover removed;

3 is a cross-sectional view of main parts inside a recess of a vane pump according to a second embodiment of the present invention;

Figure 4 is a front view of the cover of Figure 3;

Fig. 5 is the front view of the first side plate of Fig. 3;

Figure 6 is a rear view of the first side panel of Figure 3;

Fig. 7 is the front view of the second side plate of Fig. 3;

Figure 8 is a rear view of the second side panel of Figure 3;

Figure 9 is a rear view of the third side panel of Figure 3;

Figure 10 is a front view of the body of Figure 3;

Fig. 11 is a sectional view of a main part of a second embodiment of the present invention, showing a second side plate including a first check valve, a third side plate, and the body.

Figure 12A is a front view of the retainer forming part of the first one-way valve of Figure 11 as seen from the side of the body;

Figure 12B is a front view of the leaf spring forming part of the first one-way valve of Figure 11 as seen from the side of the pump body; and

Figure 12C is a front view of the sheet forming part of the first one-way valve of Figure 11 as seen from the side of the pump body.

detailed description

Hereinafter, a first embodiment of the vehicle hydraulic system of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the configuration of a vehicle hydraulic system of the present invention. The vehicle hydraulic device 10 includes a check valve 90 and a vane pump 14 that supplies working fluid to an oil pressure control device 12 serving as an oil pressure control circuit that consumes working fluid, such as an automatic transmission (A/T) or Continuously variable transmission (CVT) pulley (sheave) hydraulic cylinder, etc.

The vane pump 14 is driven by the rotation of the engine 15 . The vane pump 14 has a first suction port 22 and a second suction port 24 and a first discharge port 26 and a second discharge port 28, and the working fluid stored in the oil pan 18 passes through an oil strainer. 20 is sucked through the first suction port 22 and the second suction port 24 , and the sucked working fluid is discharged out of the pump through the first discharge port 26 and the second discharge port 28 . The vane pump 14 further has a first back pressure groove 62 and a second back pressure groove 64 that supply back pressure to a plurality of vanes 81 that suck and discharge working fluid. Working fluid is sent from the suction ports 22 , 24 to the discharge ports 26 , 28 through the pump chamber P formed by the vanes 81 .

A first discharge oil passage 30 and a second discharge oil passage 31 each serving as a discharge oil passage are connected to the first discharge port 26 and the second discharge port 28 , respectively. The first discharge oil passage 30 and the second discharge oil passage 31 are further connected to the discharge oil passage 29, and serve as working fluid supply passages leading to the oil pressure control device 12, and the oil discharged from the first discharge port 26 and the second discharge port 28 The working fluid is pumped to the oil pressure control device 12 through the working fluid supply passage.

The first back pressure oil passage 35 and the second back pressure oil passage 36 each corresponding to the back pressure oil passage are connected to the first back pressure groove 62 and the second back pressure groove 64 , respectively. The check valve 90 is disposed between the first and second discharge oil passages 30 and 31 and the first and second back pressure oil passages 35 and 36 .

The suction oil passage 34 connects the first suction port 22 and the second suction port 24 of the vane pump 14 and the oil pan 18 to each other via the oil filter 20 so that the working fluid stored in the oil pan 18 is sucked into the first suction port. Inlet 22 and the second suction port 24. The return oil passage 32 returns the working fluid of the hydraulic control device 12 to the suction oil passage 34 of the vane pump 14 .

FIG. 2 is a front view showing the vane pump 14 of the vehicle hydraulic system 10 with the pump cover removed. The vane pump 14 is made up of: a body 44 having a generally cylindrical recess 16 formed therein; a generally cylindrical cam ring 70 corresponding to the pump casing, which fits within the recess 16 so as not to be inaccessible relative to the body 44. Rotation; disc-shaped side plate 37, which is installed so as to be interposed between the bottom wall surface of the recess 16 of the body 44 and the cam ring 70, wherein one flat surface and the other flat surface of the side plate 37 are respectively in contact with the bottom wall of the recess 16 The surface is in contact with the substantially circular end surface of the cam ring 70; the cylindrical rotor 74 is accommodated so that the outer peripheral surface faces the cam ring 70 with a small gap between it and the inner peripheral cam surface 78 of the cam ring 70; an inner peripheral cam surface 78, and enables one end surface in the rotation axis direction to be in sliding contact with the other flat surface of the side plate 37; a pump shaft 76, which is fixed to the rotor 74 coaxially with the rotation axis of the rotor 74 and is rotatably supported On the body 44, and according to the driving of the driving source such as the engine 15, the rotor 74 is rotated in the direction of the arrow indicated in FIG. 2 , that is, clockwise; and a pump cover (not shown), which is fastened to the body 44 so as to be in contact with the substantially circular other end surface of the cam ring 70 and to cover the opening of the concave portion 16 while being able to be in sliding contact with the other axial end surface of the rotor 74 .

The cam ring 70 has an inner peripheral cam surface 78 which is an inner peripheral surface having a substantially elliptical cross-sectional shape. The rotor 74 includes: a plurality of slits 80 corresponding to the vane receiving grooves, and the plurality of slits 80 are radially spaced from the central portion in the radial direction toward the outer peripheral surface in the entire axial direction of the outer peripheral surface at uniform intervals in the circumferential direction. and a plurality of rectangular plate-shaped vanes 81 fitted into the slits 80 . Since the slot 80 accommodates the blade, the slot 80 is also referred to as a blade receiving slot. The vane 81 is inserted into the slot 80 so that the side surface of the vane 81 in the circumferential direction of the rotor 74 can slide on the inner wall of the slot 80 facing the vane 81 in the radial direction of the rotor 74; The other end surfaces of 37 are in sliding contact with the inner wall surfaces of the pump cover respectively;

When the rotor 74 is driven to rotate, the blade 81 is pushed out from the inner wall of the slit 80 toward the radially outer side of the rotor 74 under the back pressure from the first back pressure groove 62 and the second back pressure groove 64, so that the blade 81 The radially outer end surface is pressed against the inner peripheral cam surface 78 of the cam ring 70 and slides on the inner peripheral cam surface 78 in the rotation direction of the rotor 74 in this state. Accordingly, a plurality of pump chambers P are defined by the side surfaces of the adjacent vanes 81 facing each other in the circumferential direction, the inner peripheral cam surface 78, the outer peripheral surface of the rotor 74, the other end surfaces of the side plates 37, and the inner wall surface of the pump cover. . Since the inner peripheral cam surface 78 has a substantially elliptical shape, when the rotor 74 makes one revolution, the vane 81 reciprocates twice in the slit 80 in the radial direction of the rotor 74, so that the volume of the pump chamber P increases and decreases. twice.

In the side plate 37 and the body 44, a pair of first suction port 22 and second suction port 24 communicating with the pump chamber P whose volume increases according to the rotation of the rotor 74 is formed across the pump shaft 76 so as to straddle the side plate 37 and pump body 44 both. In the side plate 37 and the body 44, a pair of first discharge port 26 and second discharge port 28 communicating with the pump chamber P whose volume decreases according to the rotation of the rotor 74 is formed across the pump shaft 76 so as to straddle the side plate 37 and body 44 both. The first discharge port 26 is located on the front side in the rotation direction of the rotor 74 with respect to the first suction port 22 . The second discharge port 28 is located on the front side in the rotation direction of the rotor 74 with respect to the second suction port 24 . Instead of forming these ports so as to span both the side plate 37 and the body 44 , it is also possible to form the ports 22 , 24 , 26 and 28 in the side plate 37 only.

The side plate 37 communicates with the inner peripheral end of the slit 80 equipped with the vane 81 defining the pump chamber P between the first suction port 22 and the first discharge port 26 . The first back pressure groove 62 and the second back pressure groove 64 that supply back pressure for pressing the vane 81 against the inner peripheral cam surface 78 are formed in a semicircular shape in the circumferential direction of the side plate 37 . The first back pressure groove 62 and the second back pressure groove 64 communicate with the first back pressure oil passage 35 and the second back pressure oil passage 36 respectively.

When the vane pump 14 is started according to the driving of the engine 15 and the rotor 74 rotates clockwise in FIG. port 24 and delivered to each pump chamber P of the vane pump 14 whose volume gradually increases as the rotor 74 rotates. As the rotor 74 rotates and the volume of the pump chamber P decreases accordingly, the working fluid sucked into the pump chamber P is discharged to the first discharge oil passage 30 and the second discharge oil passage 30 through the first discharge port 26 and the second discharge port 28 respectively. oil circuit 31. The oil pressure in the first back pressure oil passage 35 and the second back pressure oil passage 36 serves as a back pressure for pressing the radially outer end surface of the vane 81 defining the pump chamber P against the inner peripheral cam surface 78 of the cam ring 70 to supply.

The check valve 90 is provided in an oil passage connecting the first back pressure oil passage 35 and the second back pressure oil passage 36 and the first discharge oil passage 30 and the second discharge oil passage 31 to each other. When the oil pressure of the working fluid in the discharge oil passages 30, 31 discharged from the vane pump 14 is higher than the oil pressure in the back pressure oil passages 35, 36, the check valve 90 opens, and when the discharge oil discharged from the vane pump 14 When the oil pressure of the working fluid in the oil passages 30, 31 is equal to or lower than the oil pressure in the back pressure oil passages 35, 36, the one-way valve 90 is closed to prevent the flow of the working fluid. In this way, the back pressure for pressing the radially outer end surfaces of the vanes 81 defining the pump chamber P of the vane pump 14 against the inner peripheral cam surface 78 of the cam ring 70 is maintained.

Therefore, the check valve 90 is provided in the vehicle hydraulic system 10 of the first embodiment so that by maintaining the oil pressure in the back pressure oil passages 35, 36 connected to the vane pump while the vane pump 14 is stopped, even in the vane pump 14 can still operate the vane pump 14 smoothly when starting. When the oil pressure of the working fluid in the discharge oil passages 30, 31 discharged from the vane pump 14 is higher than the oil pressure in the back pressure oil passages 35, 36, the check valve 90 opens, and when the discharge oil discharged from the vane pump When the oil pressure of the working fluid in the passages 30, 31 is equal to or lower than the oil pressure in the back pressure oil passages 35, 36, the one-way valve 90 is closed to cut off the flow of the working fluid. With such a check valve 90 provided between the back pressure oil passages 35, 36 and the discharge oil passages 30, 31, the oil pressure control device 12 supplied with the working fluid from the vane pump 14 is filled with the working fluid. Then, at the point of time when the oil pressure in the discharge oil passages 30, 31 communicating with the oil pressure control device 12 has risen and exceeded the oil pressure in the back pressure oil passage, the check valve 90 is opened. Therefore, the one-way valve 90 is prevented from being repeatedly opened and closed, so that the durability of the one-way valve 90 is improved.

Furthermore, in the first embodiment, the check valve 90 is provided in the back pressure oil passages 35 , 36 supplied with the working fluid at a lower flow rate, so that the check valve 90 is provided in the back pressure oil passage 35 , 36 supplied with the working fluid at a higher flow rate. When there is the working fluid in the discharge oil passage 29 , it is possible to reduce the torque loss of the vane pump 14 especially during high-speed rotation of the vane pump 14 .

Next, a second embodiment of the present invention will be described. In the following second embodiment, those components having substantially the same functions as those of the first embodiment will be denoted by the same reference numerals, and a detailed description thereof will be omitted. The vehicle hydraulic device 10 of the second embodiment differs from the first embodiment in that the check valve 90 is built into the second side plate 40, and a plurality of side plates with oil passages accompanying the check valve are used: the first The side panel 38 , the second side panel 40 and the third side panel 42 . Therefore, only this configuration difference will be described in detail using FIGS. 3 to 11 .

FIG. 3 is a cross-sectional view of the vane pump 14 . The body 44 is provided with a first discharge opening 54 and a second discharge opening 56 communicating with the interior of the recess 16 . The third side plate 42 and the second side plate 40 are fitted inside the recess 16 of the body 44 so as not to be able to rotate relative to the body 44 . The cam ring 70 is fitted so as to be non-rotatable relative to the body 44 , and the rotor 74 housing the plurality of vanes 81 radially inside is mounted in the recess 16 of the body 44 . The first side plate 38 is fitted inside the recess 16 of the body 44 so as not to be able to rotate relative to the body 44 . The pump cover 72 is installed so as to cover the opening of the recess 16 of the body 44 , and the pump cover 72 is provided with the first suction opening 46 , the second suction opening 48 and the pump shaft insertion hole 77 through which the pump shaft 76 passes.

Descriptions of structures and functions of the plurality of vanes 81 housed in the cam ring 70 and the rotor 74 that are the same as those described in the first embodiment will be omitted. The oil passages in the vane pump 14 will be described in the order from suction to discharge of the working fluid, that is, in the order of the pump cover 72 , the first side plate 38 , the second side plate 40 , the third side plate 42 , and the body 44 . And a first one-way valve 98 and a second one-way valve 99 each functioning as a one-way valve.

FIG. 4 is a front view of the pump cover 72 . The pump cover is provided with a first suction opening 46 and a second suction opening 48 connected to the suction oil passage 34 and a pump shaft insertion hole 77 at the center of the pump cover. Since the pump shaft insertion hole 77 is also provided in each of the first side plate 38 , the second side plate 40 , the third side plate 42 and the body 44 , description of the pump shaft insertion hole 77 will be omitted from subsequent descriptions. . FIG. 5 is a front view of the first side plate 38 as seen from the side of the pump cover 72 . The first side plate 38 has a first suction opening 46 a connected to the first suction opening 46 and a second suction opening 48 a connected to the second suction opening 48 .

Since the working fluid is sent to the pump chamber P through the first suction opening 46 of the pump cover 72 of FIG. 4 and the first suction opening 46a of the first side plate 38, these openings correspond to the first suction port 22 of the first embodiment. . Since the working fluid is sent to the pump chamber P through the second suction opening 48 of the pump cover 72 and the second suction opening 48a of the first side plate 38, these openings correspond to the second suction port 24 of the first embodiment.

FIG. 6 is a rear view of the first side panel 38 . On the rear side of the first side plate 38 , a first back pressure groove 63 a and a second back pressure groove 65 a each serving as a back pressure oil passage are formed in a semicircular shape in a circumferential direction around the pump shaft insertion hole 77 . The first back pressure groove 63 a and the second back pressure groove 65 a supply back pressure to be applied to the blade 81 .

FIG. 7 is a front view of the second side plate 40 as seen from the side of the pump cover 72 . The second side plate 40 has a first back pressure groove 63b and a second back pressure groove 65b respectively used as a back pressure oil passage. The direction is formed as a semi-circular groove. The back pressure grooves 63 b , 65 b supply back pressure to be applied to the blade 81 . The openings of the first back pressure groove 63b of FIG. 8 used as a back pressure oil passage and the first bypass channel 82b overlap and communicate with each other, while the second back pressure groove 65b of FIG. Opening portions of the two bypass passages 84b overlap and communicate with each other. The first discharge groove 50b opens in the same shape and position as the first discharge groove 50c of the third side plate 42 of FIG. The second discharge groove 52c of the third side plate 42 of FIG. 9 opens in the same shape and at the same position, and communicates with the second discharge opening 56 of the body. Since the first discharge groove and the second discharge groove carry the working fluid from the pump chamber P, these grooves correspond to the first discharge port 26 and the second discharge port 28 of the first embodiment. The first suction groove 58 and the second suction groove 60 are formed at positions corresponding to the first suction opening 46 a and the second suction opening 48 a provided in the first side plate 38 across the rotor 74 , and since the first suction groove 58 And the second suction groove 60 has a wide opening, and thus supplies the amount of working fluid required for the pump chamber P defined by the vane 81 .

FIG. 8 is a rear view of the second side panel 40 . On the rear side of the second side plate 40, the first discharge groove 50b and the second discharge groove 52b are fully open, and the first bypass channel 82b holding the first check valve 98 and the opening holding the second check valve 99 are provided. The second bypass channel 84b. Since the first bypass passage 82b and the second bypass passage 84b of FIG. 8 are partially opened, these bypass passages are respectively in partial communication with the first back pressure groove 63b and the second back pressure groove 65b.

FIG. 9 is a rear view of the third side panel 42 . On the rear side of the third side plate 42, the first discharge groove 50c and the second discharge groove 52c are fully opened, and a first bypass passage 82c and a second bypass passage 84c are formed. The first bypass passage 82c and the second bypass passage 84c are each formed by two semicircular through grooves.

Figure 10 is a front view of the body. There is a circular recess 16 opened at one end formed in the outer central portion of the body 44 which has a cylindrical shape with one end closed. The first discharge opening 54 connected to the first discharge oil passage 30 is formed so as to penetrate the bottom wall of the body 44 . Similarly, the second discharge opening 56 connected to the second discharge oil passage 31 is formed so as to penetrate the bottom wall of the body 44 . The bottom wall further has a first bypass groove 86 formed by an annular groove at a position corresponding to that of the second side plate 40 and a groove providing communication between the annular groove and the first discharge opening 54 . The position of the first bypass passage 82b is formed. Furthermore, the bottom wall has a second bypass groove 88 formed by an annular groove corresponding to the position of the second side plate 40 and a groove providing communication between the annular groove and the second discharge opening 56 . The position of the second bypass channel 84b is formed.

11 is a sectional view of main parts, showing the second side plate 40 including one of the first check valve 98 and the second check valve 99 , the third side plate 42 , and the body 44 . The first one-way valve 98 and the second one-way valve 99 are respectively held in the first bypass passage 82b and the second bypass passage 84b of the second side plate 40, and are similarly formed by three members, namely, the holder 92. , Leaf spring 94 and thin plate 96 are made up. Hereinafter, the first check valve 98 will be described as a representative, while the description of the second check valve 99 will be omitted.

12A , 12B and 12C are front views of the retainer 92 , leaf spring 94 and thin plate 96 constituting the first check valve 98 as seen from the side of the body 44 . The holder 92 and the leaf spring 94 have ring shapes. The thin plate 96 has a disk shape with a circular opening at the center. The retainer 92 holds the leaf spring 94 within the first bypass passage 82b and the second bypass passage 84b. The plate spring 94 exerts a force for pressing the thin plate 96 against the cylindrical member provided at the center of the bypass passage 82 c of the third side plate 42 . Under the force of the leaf spring 94, the circular opening at the center of the thin plate 96 contacts the surface of the third side plate 42, so that the opening of the thin plate 96 is closed and prevents the flow of working fluid. Therefore, the thin plate 96 constituting a part of the first check valve 98 has one side surface in contact with the working fluid on the discharge opening side and the other side surface in contact with the working fluid on the back pressure groove side. Therefore, when the oil pressure of the working fluid at the first discharge opening 54 discharged from the vane pump 14 is higher than the oil pressure in the back pressure grooves of the rotor 74, the first side plate 38, and the second side plate 40, the oil passage is opened. , and when the oil pressure is equal to or lower than the oil pressure in the back pressure tank, the oil passage is closed and the flow of the working fluid is blocked. In this way, the back pressure for pressing the radially outer end surfaces of the vanes 81 defining the pump chamber P of the vane pump 14 against the inner peripheral cam surface 78 of the cam ring 70 is maintained. Although the members constituting the first check valve 98 have been described as having a circular shape in front view in the second embodiment, these members do not have to be particularly circular, and instead may have a square or polygonal shape, for example. .

Therefore, the vehicular hydraulic system 10 of the second embodiment is provided with the first check valve 98 and the second check valve 99 which allow the first back pressure groove 62 inside the rotor 74 of the vane pump to be maintained when the vane pump 14 is stopped. and the oil pressure in the second back pressure tank 64, so that the vane pump 14 can be smoothly operated even when the vane pump 14 is started.

The oil pressure control device 12 supplied with working fluid from the vane pump 14 through the first check valve 98 and the second check valve 99 has been filled with the working fluid, and the discharge oil passages 30 , 31 communicated with the oil pressure control device 12 When the oil pressure in the back pressure oil passage 35 and 36 rises and exceeds the oil pressure in the back pressure oil passage 35, 36, the first check valve 98 and the second check valve 99 are opened. Therefore, the first check valve 98 and the second check valve 99 are prevented from being repeatedly opened and closed, so that the durability of the first check valve 98 and the second check valve 99 is improved.

Also, when the first check valve 98 and the second check valve 99 are set at a lower flow rate than when the check valve 90 is set in the discharge oil passage 29 supplied with working fluid at a higher flow rate, When the working fluid is supplied into the first bypass passage 82b and the second bypass passage 84b, the torque loss of the vane pump 14 during high-speed rotation of the vane pump 14 can be particularly reduced.

Although the present invention has been described in detail above with reference to the accompanying drawings, the present invention can also be implemented in other embodiments, and various modifications can be added within the scope of the present invention.

For example, in the vane pumps 14 of the first and second embodiments, the cam ring 70 having the inner peripheral cam surface 78 is fitted in the recess 16 of the pump body 44 . However, the present invention is not limited thereto, and the cam ring may be omitted, for example, by forming the inner peripheral cam surface 78 facing the outer peripheral surface of the rotor 74 directly on the inner peripheral surface of the recess 16 of the body 44 .

Although the vane pump of the second embodiment is provided with two check valves 98, 99, the present invention is not limited thereto, and the number of check valves may be one or more.

Although the vane pump of the second embodiment has been described using three types of side plates, the present invention is not limited thereto. For example, it is also possible to omit the first side plate by machining the back pressure grooves 63a, 65a of the first side plate in the cover 72, or by machining a Bypass the slot to omit the third side plate 42 and reduce the number of side plates. Alternatively, the number of side plates can be increased to make the machining of the oil passage easier.

Claims (2)

1. a kind of vehicle hydraulic device, it includes vane pump and oil pressure control circuit, and the vane pump is revolved by engine driving Turn, the vane pump includes pump case, multiple blades and rotor, the pump case has the inner circumferential cam of elliptical shape in cross-section Face, the multiple blade is arranged in the pump case, and the rotor is provided with blade containment groove, and the blade containment groove holds The multiple blade is received so as to radially moving in the rotor；And

The oil pressure control circuit includes back pressure oil circuit and discharge oil circuit, and the back pressure oil circuit is configured to back pressure being supplied to The multiple blade in the blade containment groove, the discharge oil circuit is configured to：(i) guiding is discharged from the vane pump Working fluid, and the working fluid is supplied to the device in addition to the vehicle hydraulic device, the vehicle by (ii) Hydraulic means is characterised by also including：

Check valve, it is arranged between the back pressure oil circuit and the discharge oil circuit, and the check valve is configured to：(i) from When the oil pressure of the working fluid in the discharge oil circuit of the vane pump discharge is higher than the oil pressure in the back pressure oil circuit Open, and (ii) being equal to from the oil pressure of the working fluid in the discharge oil circuit that the vane pump is discharged or The flowing of the working fluid is prevented during less than the oil pressure in the back pressure oil circuit.

2. a kind of vehicle hydraulic device, it is characterised in that including：

Vane pump, it is rotated by engine driving, and the vane pump includes pump case, multiple blades, rotor and check valve,

The pump case has the inner circumferential cam surface of elliptical shape in cross-section,

The multiple blade is arranged in the pump case,

The rotor is provided with blade containment groove, and the blade containment groove accommodates the multiple blade so as in the rotor Radially move,

The check valve is configured to open to allow the flowing of working fluid and close to cut off the institute of the working fluid Flowing is stated, and

Oil pressure control circuit, it includes back pressure oil circuit and discharge oil circuit,

The back pressure oil circuit is configured to back pressure supplied to the multiple blade in the blade containment groove,

The discharge oil circuit is configured to：(i) working fluid that guiding is discharged from the vane pump, and (ii) will be described Working fluid is supplied to the device in addition to the vehicle hydraulic device, wherein

The check valve between the back pressure oil circuit and the discharge oil circuit, and

The check valve is configured to：(i) from the working fluid in the discharge oil circuit that the vane pump is discharged Oil pressure is opened when being higher than the oil pressure in the back pressure oil circuit, and (ii) is from the discharge oil circuit that the vane pump is discharged The working fluid the oil pressure be equal to or less than the back pressure oil circuit in the oil pressure when prevent the working fluid The flowing.