JP6794290B2 - Vehicle hydraulic control - Google Patents

Description

The present invention relates to a vehicle hydraulic control device that controls the flow of pressure oil supplied to a transmission.

As a device of this type, a device for suppressing vibration of a hydraulic control valve of an automatic transmission has been conventionally known (see, for example, Patent Document 1). In the device described in Patent Document 1, an oil passage with an orifice is connected to an oil chamber facing the end face of the spool, and the oil passage to and from the oil chamber is restricted by the orifice. Obtains a damping effect during operation.

Japanese Unexamined Patent Publication No. 5-164223

However, in the device described in Patent Document 1, if air stays in the oil chamber facing the end face of the spool, the damping effect is impaired and the vibration of the hydraulic control valve (spool) cannot be sufficiently suppressed.

The vehicle hydraulic control device according to one aspect of the present invention includes a control valve inserted in an oil passage that guides pressure oil from a hydraulic source to a transmission. The control valve is connected to the valve body, the spool that slides in the valve body according to the pilot pressure acting on the pilot chamber provided in the valve body, and the pilot chamber, and the oil to the pilot chamber. The first oil passage having a throttle portion that restricts inflow and outflow, one end surface faces the end wall inside the valve body, and the other end surface faces the end face of the spool with the pilot chamber in between, making it slidable inside the valve body. A valve body provided, a second oil passage for guiding pressure oil between one end surface and an end wall of the valve body, and a third oil having one end open to the atmosphere and the other end connected to the pilot chamber. It includes a road and an urging member that urges the valve body toward the end wall. The valve body moves to the first position where the third oil passage and the pilot chamber are communicated by the urging force of the urging member, and resists the urging force of the urging member by the pressure oil guided through the second oil passage. Then, it is provided so as to move to the second position where the communication between the third oil passage and the pilot chamber is cut off.

According to the present invention, since the air in the pilot chamber can be discharged to the outside through the third oil passage, the pilot chamber becomes oil-tight and a good damping effect can be exhibited by the throttle portion.

The figure which shows schematic the power transmission system of the vehicle to which the hydraulic control device which concerns on embodiment of this invention is applied. The hydraulic circuit diagram which shows the structure of the hydraulic control device which concerns on embodiment of this invention. FIG. 5 is a cross-sectional view showing a main configuration of a pressure control valve as a comparative example of the hydraulic control device according to the embodiment of the present invention. The figure which shows the schematic structure of the pressure control valve of FIG. 3A. The figure which shows an example of the operation by the pressure control valve of FIG. 3A. The figure which shows an example of the operation following FIG. 4A. The figure which shows an example of the operation following FIG. 4B. FIG. 5 is a cross-sectional view showing a configuration of a main part of a pressure control valve constituting the hydraulic control device according to the embodiment of the present invention in an engine stopped state. FIG. 5 is a cross-sectional view showing a configuration of a main part of a pressure control valve constituting the hydraulic control device according to the embodiment of the present invention in an engine operating state. The figure which shows an example of the operation of the pressure control valve which constitutes the hydraulic control device which concerns on embodiment of this invention in the engine stop state. The figure which shows an example of the operation in the engine operation state of the pressure control valve which comprises the hydraulic control device which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6B. FIG. 1 is a diagram schematically showing a power transmission system of a vehicle to which the hydraulic control device according to the embodiment of the present invention is applied. In FIG. 1, the torque of the engine 1 is transmitted to the drive wheels 3 via the power transmission mechanism 2. The power transmission mechanism 2 has a torque converter 2A and a transmission 2B.

The transmission 2B includes a continuously variable transmission mechanism (CVT) 20 and a forward / backward switching mechanism 30. The continuously variable transmission mechanism 20 includes a drive pulley 21 arranged along the main shaft 2a, a driven pulley 22 arranged along a counter shaft 2b parallel to the main shaft 2a, and a drive pulley 21 and a driven pulley 22. It has an endless belt 23 that is hung between the pulleys and transmits torque between the pulleys 21 and 22.

The drive pulley 21 has a fixed pulley half body 21a arranged so as to be relatively rotatable and axially immovable with respect to the main shaft 2a, and a fixed pulley half body 21a which is not relatively rotatable and axially movable relative to the main shaft 2a. It has a movable pulley half body 21b arranged so as to be possible. The driven pulley 22 has a fixed pulley half body 22a arranged so as not to rotate relative to the counter shaft 2b and cannot move relative to the axial direction, and a fixed pulley half body 22a which cannot rotate relative to the counter shaft 2b and moves relative to the fixed pulley half body 22a. It has a movable pulley half body 22b arranged so as to be possible.

Oil chambers 21c and 22c are provided on the axial sides of the movable pulley half bodies 21b and 22b, respectively. The movable pulley halves 21b and 22b are driven by the oil pressure (pulley side pressure) acting on the oil chambers 21c and 22c, respectively, which changes the groove widths of the pulleys 21 and 22 and eliminates the gear ratio of the transmission 2B. You can shift gears.

The forward / backward switching mechanism 30 includes a forward clutch 31, a reverse brake 32, and a planetary gear device 33. The sun gear of the planetary gear device 33 is fixed to the main shaft 2a, and the ring gear is fixed to the fixed pulley half body 21a of the drive pulley 26 via the forward clutch 31. A pinion is arranged between the sun gear and the ring gear of the planetary gear device 33, and the pinion is connected to the reverse brake 32 via a carrier.

The forward clutch 31 and the reverse brake 32 are engaged and disconnected by hydraulic pressure, respectively. When the forward clutch 31 is engaged and the reverse brake 32 is disengaged, the drive pulley 21 is driven in the same forward direction as the main shaft 2a. When the forward clutch 31 is disengaged and the reverse brake 32 is connected, the drive pulley 21 is driven in the reverse direction opposite to the main shaft 2a. When the forward clutch 31 is disengaged and the reverse brake 32 is disengaged, the power transmission to the drive pulley 21 via the forward / backward switching mechanism 30 is cut off.

The rotation of the counter shaft 2b is transmitted to the secondary shaft 2c via a gear. The rotation of the secondary shaft 2c is transmitted to the drive wheels 3 via the gear and the differential mechanism 34, whereby the vehicle travels.

The flow of pressure oil to the power transmission mechanism 2 is controlled by the flood control device. FIG. 2 is a hydraulic circuit diagram showing a schematic configuration of the flood control device 100 according to the embodiment of the present invention. Note that FIG. 2 shows a hydraulic circuit mainly corresponding to the transmission 2B, and a part of the hydraulic circuit which is a characteristic configuration of the present embodiment is not shown.

As shown in FIG. 2, the hydraulic control device 100 has a hydraulic pump 41 driven by the engine 1. The oil discharged from the hydraulic pump 41 is guided to the pressure control valve 42 via the oil passage L1 and is adjusted to a predetermined set pressure by the pressure control valve 42. The pressure-adjusted pressure oil (line pressure) is guided to the pressure control valves 43 and 44 via the oil passage L2 and to the pressure control valve 45 via the oil passage L3. The excess pressure oil discharged from the pressure control valve 42 is used as a lubricating oil or the like.

The pressure oil guided to the pressure control valve 45 is adjusted (decompressed) to a predetermined set pressure. The pressure-adjusted pressure oil (control pressure) is guided to the electromagnetic proportional valves 46 to 48, respectively, via the oil passages L4, L5, and L6. The electromagnetic proportional pressure reducing valves 46 to 48 are electromagnetic proportional pressure reducing valves that output a hydraulic pressure according to the amount of energization of the solenoid. The pressure oil adjusted (depressurized) by the electromagnetic proportional valve 46 is guided to the directional control valve 49. The directional control valve 49 is switched according to the shift operation of the driver, and the flow of the pressure oil to the forward clutch 31 and the reverse brake 32 is switched by switching the directional switching valve 49.

The pressure oil adjusted (depressurized) by the electromagnetic proportional valves 47 and 48 acts as a pilot pressure on the pressure control valves 43 and 44 via the oil passages L7 and L8, and the pressure control valves 43 and 44 act on the pilot pressure. The pressure on the pulley side is adjusted (decompressed) accordingly. The pressure oil regulated by the pressure control valve 43 is guided to the oil chamber 21c of the drive pulley 21 via the oil passage L9 and drives the movable pulley half body 21b. The pressure oil regulated by the pressure control valve 44 is guided to the oil chamber 22c of the driven pulley 22 via the oil passage L10, and drives the movable pulley half body 22b. Between the line pressure downstream of the pressure control valve 42, the control pressure downstream of the pressure control valve 45, and the pilot pressure downstream of the electromagnetic proportional valves 47 and 48, line pressure> control pressure> pilot pressure. A magnitude relationship is established.

The above-mentioned hydraulic control device 100 is integrally configured as a valve unit, and is housed between the transmission 2B and the oil pan. The valve unit is configured by vertically separating a plurality of valve mechanisms such as a pressure control valve and an electromagnetic proportional valve via a separate plate. Regarding this point, first, a comparative example of the present embodiment will be described.

FIG. 3A is a cross-sectional view mainly showing a part of a valve unit as a comparative example of the present embodiment, specifically, a pressure control valve 440 corresponding to a pressure control valve 44 for a driven pulley, and FIG. 3B is a cross-sectional view. It is a figure which shows the schematic structure of this pressure control valve 440. Note that FIG. 3B is shown flipped horizontally with respect to FIG. 3A.

As shown in FIG. 3A, the pressure control valve 440 has a valve body 441 attached to the upper surface of the separate plate 50 and a spool 442 slidably arranged in the internal space SP0 of the valve body 441. Oil chambers SP1 and SP2 are formed at both ends of the internal space SP0 between the spools 442 and both ends. The oil chambers SP1 and SP2 communicate with the oil passages 53 and 54 through the through holes 51 and 52 opened in the separate plate 50. The through holes 51 and 52 are smaller than the diameters of the ports PT1 and PT2 of the pressure control valves 440 communicating with the oil chambers SP1 and SP2, respectively, and function as orifices. Hereinafter, the through holes 51 and 52 may be referred to as a diaphragm.

As shown in FIG. 3B, the oil passage 53 connected to the through hole 51 constitutes an oil passage L8 (see FIG. 2) for supplying pilot pressure, and a throttle 51 is provided in the oil passage L8. On the other hand, the oil passage 54 connected to the through hole 52 constitutes an oil passage L11 whose end is open to the atmosphere, and a throttle 52 is provided in the oil passage L11. The pressure control valve 440 constitutes an oil passages L2 and L10 (see FIG. 2) for supplying line pressure to the oil chamber 22c (FIG. 1) of the driven pulley 22 and a return oil passage for pressure oil from the oil chamber 22c. It is connected to the oil passage L12. The oil passages L2, L10, and L12 are provided in a cross section different from that shown in FIG. 3A.

A spring 443 is interposed in the oil chamber (also called the pilot chamber) SP1. One end of the spring 443 comes into contact with the end wall EW1 of the cap 445, and the other end comes into contact with the bottom of the spring receiver 444 bored in one end surface of the spool 442. The spool 442 is constantly urged toward the oil chamber SP2 by the spring 443.

In the initial state before starting the engine, one end of the spool 442 comes into contact with the side end surface (end wall EW2) of the valve body 441 by the spring force. From this state, when the line pressure is supplied to the pressure control valve 440 via the oil passage L2, the line pressure is supplied to the oil chamber 22c of the driven pulley 22 via the oil passage L10. At this time, a part of the line pressure flows to the oil chamber SP3 through the oil passage (oil hole or oil groove) 442a formed in the spool 442, and the spool 442 has the pilot chamber SP1 due to the oil pressure of the oil chamber SP3. Pushing pressure acts on the side. On the other hand, a pressing force, which is the sum of the urging force of the spring 443 and the pressing force by the pilot pressure supplied through the oil passage L8, acts on the oil chamber SP2 side.

When the pressing force of the oil chamber SP3 exceeds the pressing force of the pilot chamber SP1, the spool 442 moves to the pilot chamber SP1 side. At this time, since the volume of the pilot chamber SP1 is reduced, the pressure oil is discharged from the pilot chamber SP1 through the oil passage L8, but the discharge amount is limited by the throttle 51. On the other hand, when the spool 442 moves to the oil chamber SP2 side, the amount of compressed oil discharged from the oil chamber SP2 is limited by the throttle 52. As a result, the damping effect can be exhibited and the vibration of the spool 442 can be suppressed.

In such a pressure control valve 440, for example, after the engine is stopped, the air dissolved in the hydraulic oil precipitates and gathers to form a mass, and the air AR stays in the pilot chamber SP1 as shown in FIG. 4A. There is. In this state, as shown in FIG. 4B, when the line pressure is supplied to the oil chamber SP3 via the oil passage L2, the spool 442 is pushed in the direction of arrow A. At this time, since the air AR in the pilot chamber SP1 is compressed, the effect of restricting the movement of the spool 442 by the throttle 51 is weakened, and a sufficient damping effect cannot be exhibited. As a result, as shown by arrow B in FIG. 4C, the spool 442 may vibrate in the valve body 441, causing hydraulic pulsation. This hydraulic pulsation can cause belt slip, shift abnormality, abnormal noise, etc., and is not preferable.

In such a phenomenon, as shown by the arrow FL1 in FIG. 4B, the pressure oil flows from the oil passage L10 to the oil passage L12 as shown by the arrow FL2, rather than when the pressure oil flows from the oil passage L2 to the oil passage L10. This is especially noticeable when the pressure oil is discharged from the oil chamber 22c of the driven pulley 22. After that, when the pilot chamber SP1 becomes oily with the passage of time, the damping effect is exhibited and the vibration of the spool 442 is suppressed. In consideration of this point, in the present embodiment, the pressure control valve 44 is configured as follows in order to suppress the vibration of the spool 442 due to the retention of the air mass in the pilot chamber SP1.

5A and 5B are vertical (vertical) cross-sectional views showing a main configuration of a pressure control valve 44 constituting the hydraulic control device according to the embodiment of the present invention. FIG. 5A shows an engine stopped state, and FIG. 5B shows an engine operating state. In the following, for convenience of explanation, the vertical and horizontal directions are defined as shown in the figure, and the configuration of each part will be described according to this definition. The vertical direction is the direction of gravity, and the horizontal direction corresponds to the sliding direction of the spool 442. In the initial state of engine stop (FIG. 5A), there is an oil level HS above the pressure control valve 44, and the pressure control valve 44 is present in the oil. In FIGS. 5A and 5B, the same parts as those in FIG. 3A are designated by the same reference numerals, and the differences from FIG. 3A will be mainly described below.

The pressure control valve 44 of the present embodiment differs from the pressure control valve 440 of FIG. 3A mainly in the configuration between the pilot chamber SP1 and the end wall EW1 of the valve body 441. As shown in FIG. 5A, the spool 442, the spring 443, and the valve body 60 are inserted into the internal space SP0 of the valve body 441 in this order via the opening 446 provided at the right end of the valve body 441. Will be done. After these insertions, a cap 55 is attached to the opening 446 by, for example, press fitting, and the internal space SP0 is closed by the cap 55. The left end surface of the cap 55 constitutes the end wall EW1 inside the valve body 441.

The valve body 60 has a small diameter portion 61 on the left side and a large diameter portion 62 connected to the small diameter portion 61 on the right side and expanded in the vertical direction from the small diameter portion 61, respectively, and is a boundary between the small diameter portion 61 and the large diameter portion 62. The end surface 63 is formed on the same surface in the vertical direction. The diameter of the small diameter portion 61 is substantially equal to the diameter of the opposing spools 442, and the right end portion of the spring 443 comes into contact with the left end surface 61a of the small diameter portion 61. The right end surface 62a of the large diameter portion 62 is provided with, for example, a notch 62b over the entire circumference thereof, and the inside of the notch 62b is provided so as to be in contact with and detachable from the end wall EW1. An oil chamber SP4 is formed between the right end surface 62a of the valve body 60 and the end wall EW1, and pressure oil can be supplied to the oil chamber SP4 through a through hole 56 opened in the separate plate 50. .. The through hole 56 has a larger diameter than the through holes 51 and 52, and pressure oil can be supplied to the oil chamber SP4 without using the through hole 56 as a throttle.

In the valve body 441, a first inner peripheral wall surface 441a on which the outer peripheral surface of the small diameter portion 61 slides and a second inner peripheral wall surface 441b on which the outer peripheral surface of the large diameter portion 62 slides face the internal space SP0. Are provided on the left and right respectively. A step portion 441c is formed between the first inner peripheral wall surface 441a and the second inner peripheral wall surface 441b. In the vicinity of the step portion 441c, a through hole 57 is opened in the vertical direction at the upper portion (for example, the uppermost portion) of the second inner peripheral wall surface 441b. The end of the through hole 57 is opened to the atmosphere, and the air in the internal space SP0 can be discharged to the outside through the through hole 57.

As shown in FIG. 5A, in the initial state of stopping the engine, the right end surface 62a of the valve body 60 and the end wall EW1 of the valve body 441 (cap 55) come into contact with each other. At this time, the left end surface 61a of the valve body 60 moves to the right of the step portion 441c, and the through hole 57 of the valve body 441 and the pilot chamber SP1 communicate with each other.

On the other hand, in the engine operating state, as shown in FIG. 5B, the valve body 60 moves to the left and the end surface 63 between the small diameter portion 61 and the large diameter portion 62 comes into contact with the step portion 441c. At this time, the communication between the through hole 57 and the pilot chamber SP1 is blocked by the valve body 60.

The main operation of the pressure control valve 44 according to the present embodiment will be described. 6A and 6B are diagrams showing an example of the operation of the pressure control valve 44, respectively, and correspond to the operations during the engine stop and operation, respectively. As shown in FIG. 6A, the oil passage L13 (through hole 56 in FIG. 5A) communicating with the oil chamber SP4 between the valve body 60 and the cap 55 is connected to the oil passage L6 upstream of the electromagnetic proportional valve 48. .. Since the pressure oil is not supplied to the oil chamber SP4 while the engine is stopped, the valve body 60 is pushed to the right by the urging force F1 of the spring 443 and comes into contact with the end face (end wall EW1) of the cap 55. The position of the valve body 60 at this time is called the right end position.

When the valve body 60 is at the right end position, the oil passage L14 (through hole 57 in FIG. 5A) of the valve body 441 and the pilot chamber SP1 communicate with each other, so that the air AR in the pilot chamber SP1 (see FIG. It is discharged to the outside through. Therefore, the pilot chamber SP1 becomes oil-tight, and it is possible to prevent a mass of air AR from staying in the pilot chamber SP1 when the engine is stopped.

In this state, when the engine 1 is started and the pressure oil is supplied to the oil passage L6, as shown in FIG. 6B, the pressing force F2 (the first) due to the oil pressure of the oil chamber SP4 is applied to the right end surface 62a of the valve body 60. 1 Pressing force) acts. On the other hand, a pressing force (referred to as a second pressing force), which is the sum of the urging force F1 of the spring 443 and the pressing force F3 due to the oil pressure of the pilot chamber SP1, acts on the left end surface 61a of the valve body 60.

In the present embodiment, the pressure receiving area of the valve body 60 and the pressure acting on the oil chambers SP1 and SP4 are set so that the relationship of the first pressing force> the second pressing force is always established during engine operation. Specifically, by branching the oil passage L13 from the oil passage L6, pressure oil having a higher pressure than that of the pilot chamber SP1 is always supplied to the oil chamber SP4. Therefore, the relationship of 1st pressing force> 2nd pressing force can be easily satisfied, whereby the valve body 60 is pushed to the left until the end face 63 abuts on the stepped portion 441c of the valve body 441. .. The position of the valve body 60 at this time is called the left end position.

When the valve body 60 moves to the left end position, the oil passage L14 is blocked by the outer peripheral surface of the valve body 60. As a result, a desired pilot pressure can be generated in the pilot chamber SP1 according to the operation of the electromagnetic proportional valve 48. Since the hydraulic oil from the hydraulic pump 41 is supplied to the oil chamber SP4 via the oil passage L13 during the engine operation, the valve body 60 is always in the left end position. At this time, the air AR in the pilot chamber SP1 has already been discharged through the oil passage L14. Therefore, for example, when changing the gear ratio from the Low side to the High side, that is, when the spool 442 is moved to the right and the pressure oil is discharged from the oil chamber 22c of the driven pulley 22 via the pressure control valve 44, etc. Also, a good damping effect can be exhibited by the aperture 51.

According to this embodiment, the following effects can be obtained.
(1) The vehicle hydraulic control device 100 according to the present embodiment has a pressure control valve 44 inserted in oil passages L2 and L10 for guiding pressure oil from a hydraulic pump 41 to a transmission 2B (for example, a driven pulley 22). Prepare (Fig. 2). The pressure control valve 44 is connected to the valve body 441, the spool 442 sliding in the valve body 441, and the pilot chamber SP1 according to the pilot pressure acting on the pilot chamber SP1 provided in the valve body 441. At the same time, the oil passage L8 having a throttle 51 for restricting the inflow and outflow of oil into the pilot chamber SP1, one end surface (right end surface) 62a is the end wall EW1 in the valve body, and the other end surface (left end surface) 61a is the pilot chamber. The pressure oil is guided between the valve body 60 slidably provided in the valve body 441 and the right end surface 62a of the valve body 60 and the end wall EW1 so as to face the right end surface of the spool 442 with the SP1 in between. It includes an oil passage L13, an oil passage L14 having one end open to the atmosphere and the other end connected to the pilot chamber AP1, and a spring 443 that urges the valve body 60 toward the end wall EW1 (FIG. 5A). , FIG. 6A). The valve body 60 moves to the right end position where the oil passage L14 and the pilot chamber SP1 communicate with each other by the urging force F1 of the spring 443, and resists the urging force F1 of the spring 443 by the pressure oil guided through the oil passage L13. It is provided so as to move to the left end position where the communication between the oil passage L14 and the pilot chamber SP1 is cut off (FIGS. 6A and 6B).

With this configuration, the air AR retained in the pilot chamber SP1 can be discharged to the outside before the engine is operated, so that the pilot chamber SP1 becomes oil-tight. Thereby, for example, even when the pressure oil is discharged from the oil chamber 22c of the driven pulley 22 via the pressure control valve 44 during engine operation, the good damping effect of the throttle 51 can be exhibited. As a result, the vibration of the spool 442 of the pressure control valve 44 can be suppressed, and the generation of abnormal noise or the like can be prevented.

(2) The vehicle hydraulic control device 100 further has a hydraulic circuit that adjusts the hydraulic pressure so that the pressure of the pressure oil guided through the oil passage L13 becomes larger than the pressure of the pressure oil passed through the oil passage L8. Provide (FIGS. 2 and 6A). That is, the oil passage L13 is branched from the oil passage L6 upstream of the electromagnetic proportional valve 48 so that the control pressure higher than the pilot pressure is guided to the oil passage L13. As a result, the oil chamber SP4 always has a higher pressure than the pilot chamber SP1 during engine operation, so that the valve body 60 can be easily moved to the left end position and the oil passage L14 can be maintained in the closed state. Therefore, a desired pilot pressure can be generated in the pilot chamber SP1 according to the operation of the electromagnetic proportional valve 48, and the pressure control valve 44 can be operated satisfactorily.

(3) The valve body 441 limits the amount of movement of the valve body 60 to the left when the pressure oil is guided to the oil chamber SP4 via the oil passage L13, and sets the valve body 60 to a predetermined left end value. It has a stepped portion 441c to be held (FIGS. 5B and 6B). As a result, the valve body 60 is always held at a predetermined position during engine operation, so that stable operation by the pressure control valve 44 can be realized.

(4) The transmission 2B has a continuously variable transmission mechanism 20 that transmits power via the endless belt 23, and the endless belt 23 is hung around the pressure control valve 44 via the oil passages L1, L2, and L10. It is configured to output the driving pressure for changing the width of the pulley groove (FIGS. 1 and 2). As described above, the hydraulic control device 100 of the present embodiment is applied to the pulley of the continuously variable transmission mechanism 20, particularly the pressure control valve 44 that controls the flow of pressure oil to the driven pulley 22. In such a pressure control valve 44, if the air AR is retained in the pilot chamber SP1, the spool 422 is noticeable when the gear ratio of the continuously variable transmission mechanism 20 is changed from Low to High after the engine is started. Vibration may occur. In this respect, in the present embodiment, since the air in the pilot chamber SP1 is discharged to the outside before the engine is started, the vibration of the spool 422 can be effectively suppressed.

In the above embodiment, the hydraulic control device 100 is configured so that the valve body 60 is slidably provided alongside the spool 442 inside the valve body 441, and the hydraulic control device 100 is used as a pressure control valve for driving a driven pulley. Although applied to 44, the hydraulic control device of the present invention changes the width of the pulley groove around which the endless belt 23 (power transmission member) is hung through the oil passage, such as the pressure control valve 43 for driving the drive pulley. The same can be applied to other control valves that output the driving pressure for the purpose. In particular, by applying it to the pressure control valve 43 for driving the drive pulley, the pressure oil is discharged from the oil chamber 21c of the drive pulley 21 via the pressure control valve 43 by shifting the gear ratio to the Low side when the vehicle is stopped. Vibration at the time of discharge can be effectively suppressed. The transmission 2B may be other than a continuously variable transmission, and the present invention may be similarly applied to various control valves inserted in an oil passage that guides pressure oil from a hydraulic source such as a hydraulic pump 41 to a transmission. Can be done.

In the above embodiment (FIG. 6A), an oil passage L8 (first oil passage) having a throttle 51 for restricting the inflow and outflow of oil into the pilot chamber SP1, one end surface 62a of the valve body 60, and the end wall of the valve body 441. An oil passage L13 (second oil passage) for guiding pressure oil to and from the EW1 and an oil passage L14 (third oil passage) having one end open to the atmosphere and the other end connected to the pilot chamber SP1. Although the configuration includes the above, the configurations of the first oil passage, the second oil passage, and the third oil passage are not limited to those described above. In the above embodiment, the pilot chamber SP1 is provided with a spring 443 to urge the valve body 60 toward the end wall EW1, but the configuration of the urging member is not limited to this. In the above embodiment (FIGS. 6A and 6B), the valve body 60 is moved to the right end position (first position) where the oil passage L14 and the pilot chamber SP1 are communicated by the urging force of the spring 443, and the valve body 60 is moved through the oil passage L13. The valve body 60 was moved to the left end position (second position) where the communication between the oil passage L14 and the pilot chamber SP1 was cut off against the urging force of the spring 443 by the pressure oil guided by the above. Any configuration of the valve body may be used as long as it can be moved between the first-position value and the second-position value.

In the above embodiment (FIG. 6A), the oil passage L13 is connected to the oil passage L6 upstream of the electromagnetic proportional valve 48 to guide the control pressure to the oil chamber SP4. Instead, for example, the oil passage L13 is used. It may be connected to the oil passage L3 upstream of the pressure control valve 45 to guide the line pressure to the oil chamber SP4. That is, the oil pressure is adjusted so that the pressure of the pressure oil guided through the oil passage L13 (second oil passage) becomes larger than the pressure of the pressure oil passed through the oil passage L8 (first oil passage). If this is the case, the configuration of the hydraulic circuit as the pressure adjusting means is not limited to that described above. If the relationship of 1st pressing force> 2nd pressing force is satisfied during engine operation, the magnitude relationship between the pilot pressure supplied to the pilot chamber SP1 and the pressure supplied to the oil chamber SP4 is not limited to the above. .. For example, by forming a hydraulic circuit so that the pilot pressure and the pressure supplied to the oil chamber SP4 are equal to each other and adjusting the pressure receiving areas on the left and right sides of the valve body 60, the first pressing force during engine operation is second. It may be made larger than the pressing force. In the above embodiment (FIG. 6B), a step portion 441c is provided on the inner wall of the valve body 441 to limit the amount of movement of the valve body 60 when the pressure oil is guided through the oil passage L13, and the valve body 60 is set to the left end. Although it is held at the position, the configuration of the movement restriction unit is not limited to this.

The above description is merely an example, and the present invention is not limited to the above-described embodiments and modifications as long as the features of the present invention are not impaired. It is also possible to arbitrarily combine one or a plurality of the above-described embodiments and the modified examples, and it is also possible to combine the modified examples.

2B transmission, 20 continuously variable transmission, 22 pulley, 23 endless belt, 41 hydraulic pump, 44 pressure control valve, 48 electromagnetic proportional valve, 51 throttle, 60 valve body, 441 valve body, 441c stepped part, 442 spool, 443 Spring, EW1 end wall, L8 oil passage (1st oil passage), L13 oil passage (2nd oil passage), L14 oil passage (3rd oil passage), SP1 pilot chamber, SP4 oil chamber

Claims (4)

Equipped with a control valve inserted in the oil passage that guides the pressure oil from the flood control source to the transmission.
The control valve
With the valve body
A spool that slides in the valve body according to the pilot pressure acting on the pilot chamber provided in the valve body.
A first oil passage that is connected to the pilot chamber and has a throttle portion that limits the inflow and outflow of oil into the pilot chamber.
A valve body slidably provided in the valve body, with one end facing the end wall in the valve body and the other end facing the end face of the spool with the pilot chamber in between.
A second oil passage for guiding pressure oil between one end surface of the valve body and the end wall,
A third oil passage, one end open to the atmosphere and the other end connected to the pilot chamber,
A urging member that urges the valve body toward the end wall,
The valve body moves to the first position where the third oil passage and the pilot chamber are communicated by the urging force of the urging member, and the urging is performed by the pressure oil guided through the second oil passage. A vehicle hydraulic control device characterized in that it is provided so as to move to a second position that cuts off communication between the third oil passage and the pilot chamber against the urging force of a member. In the vehicle hydraulic control device according to claim 1.
A pressure adjusting means for adjusting the oil pressure so that the pressure of the pressure oil guided through the second oil passage becomes larger than the pressure of the pressure oil passed through the first oil passage is further provided. Vehicle hydraulic control device. In the vehicle hydraulic control device according to claim 1 or 2.
The valve body is characterized by having a movement limiting portion that limits the amount of movement of the valve body when the pressure oil is guided through the second oil passage and holds the valve body at the second position value. The hydraulic control device for the vehicle. In the vehicle hydraulic control device according to any one of claims 1 to 3.
The transmission has a continuously variable transmission mechanism that transmits power via an endless band-shaped power transmission member, and the control valve has a width of a pulley groove around which the power transmission member is hung through the oil passage. A vehicle hydraulic control device characterized in that it is configured to output a drive pressure for changing.

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