JP2007127150A - Selector valve and suspension device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suspension device for a vehicle in which a selector valve for switching a circulation direction of a liquid for adjusting the length of a shock absorber is built-in in a hydraulic shock-absorbing mechanism such as the shock absorber and the length of the shock absorber can be adjusted by remote operation from the outside. <P>SOLUTION: A selector valve body 27 provided with valve parts 30 at both axial ends is arranged in an inner peripheral surface of a lower end of a piston rod 4 of the shock absorber in the suspension device for the vehicle. Any one of the valve parts 30 of the selector valve element 27 is released by axially moving a valve operation member 25 inserted into a shaft hole 21 of the piston rod 4 and a circulation hole 34 of the other closed valve part and the released valve part 30 are communicated with each other from the inside of the selector valve element 27 through a radial communication hole 36 and a liquid passage 33 at a periphery of an outer peripheral part of the selector valve element 27, but circulation in an opposite direction is suppressed by a ball element 38 constituting a check valve, thereby switching the selector valve. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a switching valve for switching the flow direction of a liquid and a vehicle suspension apparatus provided with the switching valve, and more particularly to a vehicle suspension apparatus capable of adjusting the length of a shock absorber.

  As a vehicle suspension device, a suspension device has been proposed that can automatically maintain a certain vehicle height regardless of the load capacity (Patent Document 1).

  The suspension device described in Patent Document 1 includes a hydraulic shock absorbing mechanism that performs a self-pumping operation, and a pressure accumulating mechanism that is different from the hydraulic shock absorbing mechanism, and the piston rod that constitutes the hydraulic shock absorbing mechanism is changed by a change in load. When the piston rod expands and contracts, hydraulic pressure acts on the piston rod so as to return to a predetermined position. In particular, when the piston rod is extended, a self-pumping operation is performed using vibration generated in the hydraulic shock absorber when the vehicle travels. . At this time, hydraulic oil is supplied and returned between the hydraulic shock absorbing mechanism and the pressure accumulating mechanism. The hydraulic mechanism is provided with a plurality of check valves so that the hydraulic pressure acts so that the piston rod can return to a predetermined position.

Further, as another vehicle suspension device, for example, a shock absorber which is a hydraulic shock absorber is constituted by a shock absorber main body and a cylindrical portion which is attached so that the shock absorber main body can be screwed in the length direction, and the shock absorber main body, The thing which changed the length of the suspension apparatus by adjusting the relative length with this cylinder part is proposed (patent document 2).
Japanese Patent Laid-Open No. 09-310731 JP 2004-338490 A

  In the suspension system for a vehicle as shown in Patent Document 2, as a shock absorber length adjusting means, for example, a method of rotating the shock absorber main body with respect to the cylindrical portion by electric drive has been proposed. Is required. For this reason, it is conceivable that the arrangement position of the drive motor or the like is restricted due to a narrow space where the suspension device is installed. In addition, the drive motor and the like are relatively heavy, which increases the weight of the entire vehicle.

  On the other hand, as shown in Patent Document 1, if the length of the shock absorber is adjusted using hydraulic pressure in the suspension device, the drive motor is not required, but a separate pressure accumulating mechanism is required. Further, the suspension device of Patent Document 1 requires a plurality of check valves, resulting in a complicated hydraulic path. In particular, when a switching valve for switching the flow direction of liquid is arranged in a hydraulic shock absorbing mechanism such as a shock absorber, it is required to be able to switch from the outside with a compact configuration.

  The present invention has been made in view of such a point of view, and an object of the present invention is to provide a switching valve that is arranged in an elongated pipe and can switch a liquid flow direction by remote control.

  In addition, the present invention has a built-in switching valve that switches the flow direction of the liquid in order to adjust the length of the shock absorber in a hydraulic shock absorber such as a shock absorber, and the length of the shock absorber can be adjusted remotely from the outside. An object of the present invention is to provide a vehicle suspension system.

  According to a first aspect of the present invention, there is provided a switching valve having a valve body portion accommodated in one axial end portion, an axial hole formed along the axial direction, and the axial hole. A rod-shaped member formed in a radial direction with a liquid hole communicating therewith, and a valve operating rod inserted into the shaft hole of the rod-shaped member so as to be movable in the axial direction, passing through the rod-shaped member, A switching valve capable of switching a flow direction of a liquid between a liquid hole formed in a peripheral wall portion and one end side of the rod-shaped member, wherein the valve main body portion is a first valve body portion at both axial end portions. And a switching valve body in which the second valve body portion is formed and the other end side in the axial direction is connected to one end side of the valve operating rod, and the switching valve body is accommodated so as to be movable in the axial direction, and the first valve body The first valve seat portion and the second valve seat portion that are in contact with each other and the second valve body portion are axially opposite ends. The switching valve body has a first fluid passage hole and a second fluid passage hole formed on the first valve body portion side and the second valve body portion side, respectively. In addition, there is a radial liquid passage hole formed in the radial direction communicating with the first liquid passage hole and the second liquid passage hole, and from the outside to the inside of the first liquid passage hole and the second liquid passage hole. A check valve mechanism that allows only the flow of the liquid, and forms a valve fluid passage communicating with the radial fluid passage hole between the outer periphery of the switching valve body and the inner periphery of the valve seat member, and the switching The valve body can be switched between a state in which the valve fluid passage communicates with a liquid hole formed in a peripheral wall portion of the rod-like member and a state in which the valve fluid passage communicates with one end side of the rod-like member by the axial movement of the valve body. To do.

  According to a vehicle suspension system that achieves the object of the present invention, as described in claim 2, the piston rod is accommodated in the inner tube so as to be relatively movable in the axial direction, and the inner tube is disposed in the outer tube. The shock absorber is attached between the vehicle body side and the wheel side, and a coil spring is disposed between the spring seat provided at the tip of the piston rod and the spring seat provided on the outer tube, and the shaft of the spring seat In the vehicle suspension system capable of changing the directional position, the rod-shaped member in the switching valve having the above-described configuration is used as the piston rod, and the switching valve body is disposed at the lower end portion of the piston rod and inserted into the inner tube. A seal member is fixed to the outer periphery of the piston rod, and the inner tube is bounded by the seal member. The first liquid chamber is divided into a first liquid chamber and a second liquid chamber communicating with the liquid hole of the rod, and the switching valve body is moved in the axial direction by operating the valve operating rod, thereby allowing the first liquid chamber to move from the first liquid chamber. The flow of the hydraulic oil toward the second liquid chamber and the flow of the hydraulic oil toward the first liquid chamber from the second liquid chamber can be switched.

  According to the switching valve of the present invention, the valve main body portion is accommodated at one axial end portion of the rod-shaped member. For example, at the distal end portion of an elongated pipe, the peripheral wall portion of the pipe passes through the pipe from the distal end side of the pipe. The valve operating rod is moved in the axial direction between the flow direction of the liquid discharged from the liquid hole formed in the pipe and the flow direction of the liquid discharged from the tip end side of the pipe through the pipe from the liquid hole. It is possible to switch only. For this reason, in a device that is used by switching the liquid flow direction, the rod-shaped member itself is applied to the components constituting the device, so that a separate switching valve is not required and the device can be made compact. Can be planned.

  In the automotive suspension system according to the present invention, when the axial position of the spring seat is changed to adjust the vehicle height to a low vehicle height, for example, if the overall length of the shock absorber remains long, the coil spring will play and a difference will occur. If a problem occurs such as the generation of sound or damage to the suspension, or if the vehicle turns around a corner, the suspension on the inside of the vehicle will extend more than necessary and steering stability will decrease, and conversely if the vehicle height is high, If the overall length of the shock absorber remains short, the ability to follow the unevenness of the road surface when the vehicle is running will deteriorate, leading to a deterioration in ride comfort and a decrease in driving performance, and the suspension on the inside of the vehicle will extend when turning a corner. Therefore, there is a problem that the behavior of the vehicle becomes too agile.

  However, the total length of the shock absorber is adjusted, and these problems can be solved by adjusting the height position of the piston rod. However, according to the present invention, the working oil flows between the first liquid chamber and the second liquid chamber. By arranging the switching valve body that switches the direction in the lower end of the piston rod, it is not necessary to change the outer diameter of the piston rod itself, and the piston rod can be hydraulically operated by self-pumping operation without changing the outer diameter of the shock absorber. This makes it possible to move to an arbitrary position.

  Further, since the switching operation of the switching valve can be performed by moving the valve operating rod inserted through the piston rod, for example, in the axial direction, the switching valve can be easily switched.

  FIGS. 1 and 2 are diagrams showing an embodiment of a vehicle suspension system according to the present invention, and FIGS. 3 and 4 are switching valves having a check valve configuration shown in FIGS.

  FIG. 1 is a partially cutaway sectional view of a suspension device for a vehicle such as a passenger car, which is a combination of a shock absorber and a coil spring, and shows a state in which the overall length of the shock absorber is shortened as the vehicle height is adjusted low. Shows a state in which the overall length of the shock absorber is increased as the vehicle height is adjusted higher. FIG. 3 is a cross-sectional view showing a state in which the switching valve is switched in the direction of increasing the overall length of the shock absorber, and FIG. 4 is a cross-sectional view showing a state in which the switching valve is switched in a direction of shortening the overall length of the shock absorber.

  The vehicle suspension device 1 of the present embodiment includes a hydraulic shock absorber 2 and a coil spring 5 disposed between an outer tube 3 of the shock absorber 2 and a piston rod 4 of the shock absorber 2.

  The shock absorber 2 of the present embodiment has a configuration in which a hollow piston rod 4 is disposed in the inner tube 6 so as to be movable in the axial direction, and the inner tube 6 is fixed in the outer tube 3 while maintaining liquid tightness. Yes. An outer liquid chamber 7 is formed between the inner surface of the outer tube 3 and the outer surface of the inner tube 6. The inner tube 6 has a first liquid chamber 9 on the upper side of the seal member 8 and a lower side of the first seal member 8 with a first seal member 8 fixed to the outer periphery of the piston rod 4 as a boundary. The second liquid chamber 10 is separated from the second liquid chamber 10, and the second liquid chamber 10 and the outer liquid chamber 7 communicate with each other via a valve mechanism 11 that is attached to the lower end of the inner tube 6 and that damps vibrations. The first seal member 8 is fixed at a position where an oil hole 24 formed in a piston rod 4 constituting a switching valve 20 described later faces the first liquid chamber 9. A support member 15 that slides on the inner peripheral surface of the inner tube 6 is fixed to the lower end portion (right end portion in the figure) of the piston rod 4 so that the piston rod 4 can move smoothly along the axial direction. ing.

  A threaded portion 3a is formed on the outer peripheral surface of the outer tube 3, and a spring seat 12 made of a nut member is attached by screw coupling. Similarly, the spring seat is supported by a non-rotating nut member 13 that is screw-coupled. 12 is prevented from moving to the right side in the figure.

  A vehicle body side mounting unit 42 is attached to the tip end portion (left end portion in the drawing) of the shock absorber 2, and a spring receiving device 14, which is a vehicle height adjusting device, is slightly below the vehicle body side mounting unit 42. The coil spring 5 is attached between the spring receiving device 14 and the spring receiving seat 12. The length of the coil spring 5 is in the state shown in FIG.

  A spring receiving device 14 as a vehicle height adjusting device includes a ring-shaped piston 14b that forms a spring seat in a ring-shaped cylindrical portion 14a, and a ring-shaped cylindrical portion 14a and a ring-shaped cylindrical portion 14a from a hydraulic circuit (not shown). When hydraulic pressure is applied to the piston 14b, the relative distance from the ring-shaped cylindrical portion 14a becomes longer, and the vehicle height can be adjusted higher (FIG. 2).

  Conversely, when the hydraulic fluid between the ring-shaped cylinder portion 14a and the ring-shaped piston 14b is returned to the hydraulic circuit, the relative distance between the ring-shaped cylinder portion 14a and the piston 14b is shortened and the vehicle height is lowered. It can be adjusted (FIG. 1).

  If the relative height between the ring-shaped piston 14b and the ring-shaped cylindrical portion 14a is shortened and the vehicle height is adjusted to be low at the position where the vehicle height shown in FIG. 2 is high, the overall length of the shock absorber 2 remains long. If it exists, since the ring-shaped piston 14b only moves upward, the upper end of the coil spring 5 is separated from the ring-shaped piston 14b, and the coil spring 5 is idle. Also, when turning a corner, the load of the vehicle moves to the outer suspension device, and when the load of the inner suspension device is released, it is extended by the length of the shock absorber 2, so that the suspension device inside the vehicle is more than necessary. This causes a problem that it extends and causes a decrease in steering stability.

  On the other hand, when the vehicle height is adjusted higher by increasing the relative distance between the ring-shaped piston 14b and the ring-shaped cylindrical portion 14a at the position where the vehicle height shown in FIG. 1 is low, the total length of the shock absorber 2 is reduced. If it is kept short, the movable range of the shock absorber 2 is short, and the followability to the road surface unevenness deteriorates. In addition, when turning a corner, there is a problem that when the applied load is released, the suspension device on the inside of the vehicle is less stretched and the behavior of the vehicle becomes too agile.

  Therefore, by making the total length of the shock absorber 2 adjustable, the total length of the shock absorber 2 can be adjusted in accordance with the vehicle height adjustment.

  The full length adjustment mechanism of the shock absorber 2 in the present embodiment will be described below.

  1 and 2, when the hydraulic oil in the first liquid chamber 9 is sent into the second liquid chamber 10, the end face of the piston rod 4 facing the second liquid chamber 10 becomes a hydraulic pressure operating surface, and the piston rod 4 The piston rod 4 moves to the left side in the figure and extends with respect to the outer tube 3, and switches from the state of FIG. 1 to the state of FIG. In order to extend the piston rod 4 with respect to the outer tube 3, since the weight of the vehicle body is added to the piston rod 4, some force is required. The hydraulic oil in the first liquid chamber 9 is sent out into the second liquid chamber 10 by a self-pumping operation utilizing the relative vertical movement of the shock absorber 2 and the outer tube 3.

  1 and 2, when the fluid path is switched so that the hydraulic oil in the second liquid chamber 10 can be sent into the first liquid chamber 9, the hydraulic oil in the second liquid chamber 10 is received in response to the weight of the vehicle body. Enters the first liquid chamber 9, the piston rod 4 moves downward, the piston rod 4 enters the outer tube 3, and the state of FIG. 2 is changed to the state of FIG. 1, and the overall length of the shock absorber 2 is shortened. .

  Here, the first liquid chamber 9 is composed of a first seal member 8 fixed to the outer peripheral surface of the piston rod 4 and a cylindrical second seal member 16 fixed to the inner peripheral surface of the inner tube 6. The upper end of the second seal member 16 slides on the outer peripheral surface of the piston rod 4, and the outer peripheral surface of the first seal member 8 slides on the inner peripheral surface. A first liquid chamber 9 is formed on the inner peripheral surface of the second seal member 16.

  Such switching of the liquid path is performed by a switching valve 20 having a check valve configuration shown in FIGS.

  In the switching valve 20 of this embodiment, a large-diameter inner diameter portion 22 that communicates with the shaft hole 21 is formed at the lower end portion of the piston rod 4 having a hollow structure in which the shaft hole 21 is formed in the axial direction in the axial center portion. The valve body portion 23 of the switching valve 20 is arranged in the inner diameter portion 22 so as to be movable in the axial direction.

  As shown in FIG. 3, the switching valve 20 has a lower end portion of the valve operating rod 25 inserted through the shaft hole 21 of the piston rod 4 fixed to the valve body 23, and moves the valve operating rod 25 up and down in the axial direction. Thus, the valve body 23 is moved in the vertical direction. In the present embodiment, a screw member 26 is screwed into the shaft hole 21 at the upper end portion of the piston rod 4, and the valve operating rod 25 is fixed to the screw member 26. When the screwing member 26 is rotated in the reverse direction, the valve operating rod 25 moves upward while rotating around the axis. The screw-in member 26 is attached to the shaft hole 21 with oil-tightness by an oil seal member 26a, so that hydraulic oil is prevented from leaking from a liquid passage 21a described later.

  The outer diameter of the valve operating rod 25 is smaller than the inner diameter of the shaft hole 21, and a liquid passage 21 a through which hydraulic oil flows is formed between the outer peripheral surface of the valve operating rod 25 and the inner peripheral surface of the shaft hole 21. ing. A ring-shaped seal member 26b is disposed between the inner end surface of the screwing member 26 and the outer peripheral surface of the valve operating rod 25, and the hydraulic oil in the liquid passage 21a moves between the outer peripheral surface of the valve operating rod 25 and the screwing member 26. It is prevented from leaking outside through the gap between the two.

  The valve body 23 is configured such that a switching valve body 27 formed in a cylindrical shape with both end portions formed into tapered surfaces is movable in the vertical direction with respect to the valve seat member 28 provided on the inner peripheral surface of the inner diameter portion 22. The switching valve body 27 has first and second valve body portions 29 and 30 at both ends in the vertical direction formed on the tapered surface, and the valve seat member 28 is in contact with the first valve body portion 29. A first valve seat portion 31 and a second valve seat portion 32 that contacts the second valve body portion 30 are formed. The total length of the switching valve body 27 is shorter than the distance between the first valve seat portion 31 and the second valve seat portion 32 in the valve seat member 28.

  As shown in FIG. 3, when the first valve body portion 29 is in contact with the first valve seat portion 31, the second valve body portion 30 and the second valve seat portion 32 are separated from each other. As shown in FIG. 4, the first valve body portion 29 and the first valve seat portion 31 are separated in a state where the second valve body portion 30 is in contact with the second valve seat portion 32. The outer diameter of the switching valve body 27 is formed to be smaller than the inner diameter of the valve seat member 28, and hydraulic oil is interposed between the outer peripheral surface of the trunk portion of the switching valve body 27 and the inner peripheral surface of the valve seat member 28. A liquid path 33 is formed.

  The switching valve body 27 is formed with a first fluid passage hole 34 and a second fluid passage hole 35 facing the end surfaces on the first valve body portion 29 side and the second valve body portion 30 side, respectively, along the axial direction. A third liquid passage hole 36 and a fourth liquid passage hole 37 that are always in communication with the liquid passage 33 are formed along the radial direction.

  In the present embodiment, the first liquid passage hole 34 and the second liquid passage hole 35 are formed on the same axis, and the first ball body 38 is formed from the inner side of the switching valve body 27 to the inner end of the first liquid passage hole 34. Similarly, the second ball body 39 can be brought into contact with the inner end of the second liquid passage hole 35, and the first ball body 38 and the second ball body 38 are attached to both ends of the compression coil spring 41 disposed in the communication hole 40. The two-ball body 39 abuts, and the first ball body 38 and the second ball body 39 are pressed against the inner end surfaces of the first liquid passage hole 34 and the second liquid passage hole 35, respectively.

  The switching valve body 27 can communicate with the first liquid hole 34 and the second liquid hole 35 through the third liquid hole 36 and the fourth liquid hole 37, respectively. The second ball body 39 permits the movement of hydraulic oil from the first fluid passage hole 34 to the third fluid passage hole 36 and from the second fluid passage hole 35 to the fourth fluid passage hole 37, respectively, but prevents the reverse. It functions as a check valve.

  Further, the lower end portion of the valve operating rod 25 is connected to the shaft hole portion 25a communicating with the first liquid passage hole 34 of the switching valve body 27, and communicates with the shaft hole portion 25a. A radial hole portion 25b extending in the radial direction and communicating with the liquid passage 21a formed between the inner peripheral surface of the first gas passage 21 and the inner peripheral surface 21 is formed.

  When the switching valve body 27 of the switching valve 20 is moved upward and the first valve body portion 29 of the switching valve body 27 is brought into contact with the first valve seat portion 31, as shown in FIG. The hydraulic oil in the chamber 9 passes through the oil hole 24 from the liquid passage 21a through the radial hole portion 25b, the shaft hole portion 25a, and the first liquid passage hole 34, and the first ball body 38 resists the spring force of the compression coil spring 41. Then, it is pushed out, goes out to the liquid passage 33 through the third liquid passage hole 36, and is sent out to the second liquid chamber 10. At this time, even if the hydraulic oil in the second liquid chamber 10 tries to flow backward, the pressure that presses the first ball body 38 upward acts on the first ball body 38, so that the first ball body 38 is in the first state. The first fluid passage hole 34 is pressed by the inner end surface of the fluid passage hole 34 and the backflow of the hydraulic oil is prevented. Of course, since the first valve body portion 29 is in contact with the first valve seat portion 31, the liquid passage 33 and the liquid passage 21a communicate directly, and the second liquid chamber 10 and the first liquid chamber 9 are connected. There is no communication.

  In this embodiment, the switching valve element 27 is moved upward when the overall length of the shock absorber 2 is increased, and the hydraulic oil in the first liquid chamber 9 shown in FIG. 1 is discharged to the second liquid chamber 10 side. At this time, the piston rod 4 is raised by the hydraulic pressure in the second liquid chamber 10. Specifically, the piston rod 4 repeats vertical vibration with respect to the outer tube 3 when the vehicle travels. However, when the piston rod 4 moves upward, the volume of the first liquid chamber 9 is forcibly reduced. Therefore, the reduced amount of hydraulic fluid is supplied from the first liquid chamber 9 to the second liquid chamber 10, and this operation is repeated until the volume of the first liquid chamber 9 becomes substantially zero as shown in FIG. I. In the state where the switching valve body 27 is switched to the upper position shown in FIG. 3, even if the pressure in the second liquid chamber 10 becomes high, the first ball body 38 functions as a check valve, and the second liquid The hydraulic oil in the chamber 10 is not returned to the first liquid chamber 9, and the elongated piston rod 4 is not lowered.

  Next, in order to shorten the overall length of the shock absorber 2, the switching valve element 27 is moved downward as shown in FIG. 4, and into the first liquid chamber 9 having a substantially zero volume as shown in FIG. By discharging the hydraulic oil in the second liquid chamber 10, the piston rod 4 is lowered as the volume of the second liquid chamber 10 decreases.

  As shown in FIG. 4, when the switching valve body 27 is moved downward to bring the second valve body portion 30 of the switching valve body 27 into contact with the second valve seat portion 32, the hydraulic oil in the second liquid chamber 10 Pushes up the second ball body 39 against the spring force of the compression coil spring 41 through the second fluid passage hole 35, so that the hydraulic oil passing through the second fluid passage hole 35 enters the fluid path 33 from the fourth fluid passage hole 37. Reach. When the switching valve body 27 moves downward, the first valve body portion 29 and the first valve seat portion 31 are separated from each other, and the communication state between the liquid passage 33 and the liquid passage 21a is maintained. Therefore, the second liquid chamber 10 The hydraulic oil that has reached the liquid passage 33 from the liquid passage 21a is sent from the liquid passage 21a to the first liquid chamber 9 through the oil hole 24.

  At this time, even if the hydraulic oil in the first liquid chamber 9 tries to flow backward, the pressure that presses the second ball body 39 downward acts on the second ball body 39, so that the second ball body 39 is in the second state. The second fluid passage hole 35 is pressed by the inner end surface of the fluid passage hole 35 and the backflow of the hydraulic oil is prevented. Of course, since the second valve body 30 is in contact with the second valve seat 32, the liquid passage 33 and the liquid passage 21a communicate directly, and the second liquid chamber 10 and the first liquid chamber 9 are connected. There is no communication.

  In this embodiment, the switching valve element 27 is moved downward when the total length of the shock absorber 2 is shortened, and the hydraulic oil in the second liquid chamber 10 shown in FIG. 2 is discharged to the first liquid chamber 9 side. At this time, the piston rod 4 is lowered by the volume reduction of the second liquid chamber 10. Specifically, the hydraulic fluid in the second liquid chamber 10 is supplied to the first liquid chamber by a self-pumping operation using the relative vertical movement of the shock absorber 2 and the outer tube 3 of the suspension device 1 when the vehicle travels. 9 is sent out.

  That is, since the second liquid chamber 10 becomes a high pressure by the downward operation of the piston rod 4, the hydraulic oil in the second liquid chamber 10 is sent into the first liquid chamber 9. The hydraulic oil once fed into the first liquid chamber 9 is second due to the action of the second ball body 39 as a check valve when the switching valve body 27 is lowered to the lower position shown in FIG. Since there is no return to the liquid chamber 10, the state where the piston rod 4 is shortened is maintained.

  Thus, by turning the screwing member 26 in the forward and reverse directions, the switching valve body 27 of the switching valve 20 disposed at a deep position in the outer tube 3 that is an elongated pipe is moved in accordance with the vertical movement of the valve operating rod 25. The hydraulic fluid is moved in the axial direction to flow in one direction of the hydraulic oil from the first liquid chamber 9 toward the second liquid chamber 10, and the reverse of the hydraulic oil from the second liquid chamber 10 toward the first liquid chamber 9. Since the flow in the direction is switched, a switching valve can be arranged in the piston rod 4.

The partially cutaway sectional view showing the example of the suspension system for vehicles according to the present invention and showing the state where the total length of the shock absorber is short. The partially cutaway sectional view showing the example of the suspension system for vehicles according to the present invention and showing the state where the total length of the shock absorber is long. It is sectional drawing of the switching valve of the non-return valve structure provided in FIG. 1, FIG. 2, and the switching state which flows hydraulic oil from a 1st liquid chamber to a 2nd liquid chamber is shown. It is sectional drawing of the switching valve of the non-return valve structure provided in FIG. 1, FIG. 2, and the switching state which flows hydraulic oil from a 2nd liquid chamber to a 1st liquid chamber is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle suspension apparatus 2 Shock absorber 3 Outer tube 3a Screw part 4 Piston rod 5 Coil spring 6 Inner tube 7 Outer liquid chamber 8 First seal member 9 First liquid chamber 10 Second liquid chamber 11 Valve mechanism 12 Spring seat 13 Non-rotating nut member 14 Spring receiving device 14a Tube portion 14b Piston 15 Support member 16 Second seal member 20 Switching valve 21 Shaft hole 21a Fluid passage 22 Inner diameter portion 23 Valve body portion 24 Oil hole 25 Valve operation rod 25a Shaft hole portion 25b Radial hole portion 26 Screw-in member 27 Switching valve body 28 Valve seat member 29 First valve body portion 30 Second valve body portion 31 First valve seat portion 32 Second valve seat portion 33 Fluid passage 34 First fluid passage hole 35 First 2 fluid passage hole 36 3rd fluid passage hole 37 4th fluid passage hole 38 1st ball body 39 2nd ball body 40 Communication hole 41 Compression coil spring

Claims (3)

A valve body is accommodated in one axial end, a shaft hole is formed along the axial direction, and a liquid member communicating with the shaft hole is formed in a radial direction, and the shaft hole of the rod member And a valve operating rod inserted so as to be movable in the axial direction, passing through the rod-shaped member, and flowing a liquid between a liquid hole formed in a peripheral wall portion of the rod-shaped member and one end side of the rod-shaped member A switching valve that can switch directions,
The valve body portion includes a switching valve body in which a first valve body portion and a second valve body portion are formed at both axial end portions, and the other axial end portion side is connected to one end side of the valve operating rod, and the switching A valve seat member that accommodates a valve body so as to be movable in the axial direction, and has a first valve seat portion and a second valve seat portion that are in contact with the first valve body portion and the second valve body portion, respectively, opposed to both ends in the axial direction. And having
The switching valve body has a first fluid passage hole and a second fluid passage hole formed on the first valve body portion side and the second valve body portion side, respectively, and the first fluid passage hole and the second fluid passage hole. A non-return valve mechanism having a radial liquid passage hole formed in a radial direction communicating with the liquid hole and allowing only a liquid flow from the outside to the inside of the first liquid passage hole and the second liquid passage hole. A valve fluid passage communicating with the radial fluid passage hole is formed between the outer periphery of the switching valve body and the inner periphery of the valve seat member, and the valve fluid passage is formed by the axial movement of the switching valve body. The switching valve can be switched between a state communicating with a liquid hole formed in a peripheral wall portion of the rod-shaped member and a state communicating with one end of the rod-shaped member. A piston rod is accommodated in the inner tube so as to be relatively movable in the axial direction, and a shock absorber having the inner tube disposed in the outer tube is attached between the vehicle body side and the wheel side, and provided at the tip of the piston rod. In the vehicle suspension system in which a coil spring is disposed between a spring seat and a spring seat provided on the outer tube,
The rod-shaped member in the switching valve according to claim 1 is used as the piston rod, and the switching valve body is disposed at a lower end portion of the piston rod,
A seal member fixed to the outer periphery of the piston rod inserted into the inner tube, a first fluid chamber communicating with the fluid hole of the piston rod with the seal member as a boundary inside the inner tube; By dividing into a liquid chamber and operating the valve operating rod to move the switching valve body in the axial direction, the flow of hydraulic oil from the first liquid chamber toward the second liquid chamber, and the second A suspension system for a vehicle, wherein the flow of hydraulic oil from the liquid chamber toward the first liquid chamber can be switched. The suspension device for a vehicle according to claim 2, wherein a vehicle height adjusting device is configured to adjust a vehicle height by changing an axial position of a spring seat that receives the coil spring.

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