JP2008185177A - Valve structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optionally set resistance applied to the flow of the fluid in accordance with a moving direction of the fluid even in a valve structure for imparting the resistance with respect to movement of the fluid passing through a port in both directions by one valve element. <P>SOLUTION: This valve structure is provided with a valve disk 1 wherein the port 2 is formed, and the annular valve element 3 having an inner periphery and an outer periphery which are free ends and opening and closing the port 2. The valve element 3 opens the port 2 in inward opening when the fluid passes through the port 2 in one direction, and opens the port 2 in outward opening when the fluid passes the port 2 in the other direction, and a back pressure side surface 3a at least in one of the inner periphery and the outer periphery as a bending fulcrum of the valve element 3 is supported by a spring element 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improved valve structure.

  Conventionally, this type of valve structure is embodied in, for example, a piston portion of a shock absorber for a vehicle, and is an annular ring that opens and closes a port formed in the piston by being stacked on the piston and having both inner and outer peripheral ends as free ends. The valve body in this valve structure is configured such that when the fluid passes through the port in one direction, the valve opens inward and opens when the fluid passes through the port in the other direction. Those that are set to open and open ports are known.

When the valve structure configured in this way is applied to the piston portion of the shock absorber as described above, when the shock absorber is extended, the fluid tries to pass from the top to the bottom. When the inner peripheral side of the body bends downward to open the port and the shock absorber is compressed, the fluid tends to pass through the port from the lower side to the upper side. And a resistance is given to bidirectional movement of the fluid passing through the port with a single valve body (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-133201 (FIG. 1)

  Therefore, in the valve structure configured in this way, resistance is given to the bidirectional movement of the fluid passing through the port with a single valve body. Although there is a difference between opening the port with the inner opening and opening the port with the outer opening, the resistance applied to the flow of the fluid cannot be arbitrarily set according to the moving direction of the fluid.

  More specifically, in the shock absorber in which the valve structure is embodied in the piston portion, the valve structure exerts a damping force in both the pressure expansion strokes (both expansion and compression strokes). In the conventional valve structure, since the damping force for both the pressure expansion is uniquely determined and the damping force for the pressure expansion cannot be arbitrarily set, there is no degree of design freedom.

  For example, even if there is a desire to set the damping force at the time of expansion of the shock absorber, that is, the damping force at the expansion side as it is, and to set only the damping force at the time of contraction of the shock absorber, that is, the compression side damping force, In the conventional valve structure, the damping force of the expansion cannot be arbitrarily set. Therefore, if the compression side damping force is lowered, the elongation side damping force is also lowered, and the above-mentioned demand cannot be satisfied.

  Therefore, the present invention was devised in order to improve the above-mentioned problems, and an object of the present invention is to provide a valve that provides resistance to bidirectional movement of fluid passing through a port with a single valve element. Even in the structure, the resistance given to the flow of the fluid can be arbitrarily set according to the moving direction of the fluid.

  In order to solve the above-described object, the valve structure in the problem-solving means of the present invention includes a valve disk in which a port is formed, and an annular valve body that opens and closes the port with both inner and outer peripheral ends being free ends. The body is configured to open the port by opening inward when the fluid passes through the port in one direction and to open the port by opening outward when the fluid passes through the port in the other direction. The back pressure side surface on one or both of the inner periphery and the outer periphery, which is the bending fulcrum of the valve body, was supported by a spring element.

  According to the valve structure of the present invention, by adopting a configuration so as to provide resistance to bidirectional movement of fluid passing through the port with a single valve element, by setting a flexural rigidity that is a spring rigidity in the spring element. The resistance given to the fluid flow can be arbitrarily set according to the direction in which the fluid passes through the port.

  And when this valve structure is embodied in the shock absorber, the damping force can be arbitrarily set in the both strokes, and the damping force suitable for the vehicle can be exhibited in the both strokes. It becomes possible to improve the riding comfort.

  The valve structure of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to an embodiment is embodied. FIG. 2 is a longitudinal cross-sectional view of the piston portion during the expansion stroke of the shock absorber in which the valve structure according to the embodiment is embodied. FIG. 3 is a longitudinal sectional view of a piston portion during a compression stroke of a shock absorber in which a valve structure according to an embodiment is embodied. FIG. 4 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to a modification of the embodiment is embodied. FIG. 5 is a longitudinal sectional view of a piston portion of a shock absorber in which a valve structure according to another modification of the embodiment is embodied.

  As shown in FIG. 1, the valve structure of the shock absorber in one embodiment is embodied as a damping valve of the piston portion of the shock absorber. And an annular valve body 3 that opens and closes the port 2 as a free end. When the fluid passes through the port 2 in one direction, the valve body 3 opens the port 2 inwardly, and the fluid When passing through 2 in the other direction, the port 2 is set to open by opening outward, and the inner periphery of the upper surface 3a of the valve body 3 is supported by a spring washer 4 serving as a spring element.

  On the other hand, a shock absorber in which the valve structure is embodied is well known and will not be described in detail, but specifically, for example, a cylinder 40 and a head member (not shown) that seals the upper end of the cylinder 40. ), A piston rod 5 slidably passing through a head member (not shown), the piston 1 provided at the end of the piston rod 5, and two pressures separated by the piston 1 in the cylinder 40 The upper chamber 41 and the lower chamber 42, which are chambers, a sealing member (not shown) for sealing the lower end of the cylinder 40, and a cylinder internal volume change corresponding to the volume of the piston rod 5 protruding and retracting from the cylinder 40 are not shown. A cylinder or an air chamber is provided, and the cylinder 40 is filled with a fluid, specifically, hydraulic oil.

  In the valve structure, when the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the pressure in the upper chamber 41 rises and hydraulic oil flows from the upper chamber 41 to the lower chamber 42. When passing through the port 2 in the downward direction in FIG. 1, the valve body 3 bends and opens the port 2 from the inner peripheral side, giving resistance to the movement of the hydraulic oil and causing a predetermined pressure loss, On the other hand, when the damping force of the predetermined extension side is generated in the shock absorber, and the piston 1 moves downward in FIG. When hydraulic fluid passes through port 2 in the upward direction in FIG. 1 to 41, valve body 3 bends and opens port 2 from the outer peripheral side, giving resistance to the movement of the hydraulic fluid and giving a predetermined pressure loss And a predetermined damping force on the compression side is generated in the shock absorber.

  Hereinafter, the valve structure will be described in detail. A piston 1 serving as a valve disc includes an insertion hole 6 through which a piston rod 5 of a shock absorber is inserted in an axial center portion, a plurality of ports 2 penetrating the piston 1 up and down, and a piston. 1 is provided with an annular window 7 provided on the upper end side of 1 and communicating with each port 2, and an annular valve seat 8 formed so as to protrude upward in FIG. 1 on the outer peripheral side of the annular window 7. Yes.

  As described above, the tip 5 a of the piston rod 5 is inserted into the insertion hole 6 of the piston 1, and the tip 5 a is projected downward in FIG. 1 of the piston 1. The outer diameter of the tip 5a of the piston rod 5 is set to be smaller than the outer diameter on the upper side in FIG. 1 from the tip 5a, and a step portion 5b is formed at a portion where the outer diameters of the upper side and the tip are different. Yes.

  Further, an annular member 9 having a notch 9a on the outer periphery is laminated above the piston 1, and an annular adjustment washer 10 set to the same diameter as the annular member 9 is laminated above the annular member 9. A spring washer 4 that functions as a spring element is stacked above the adjustment washer 10.

  Further, the valve body 3 has an annular plate shape, the inner periphery thereof is in sliding contact with the outer periphery of the adjustment washer 10 and the annular member 9, and the outer periphery of the lower end in FIG. 1 is seated on the valve seat 8. Further, the inner circumference at the upper end in FIG. 1 is in contact with the outer circumference side at the lower end of the spring washer 4.

  Accordingly, when the shock absorber is extended, the hydraulic oil tends to pass through the port 2 in the downward direction in FIG. 1, so that the pressure from the upper chamber 41 side acts on the upper surface 3 a of the valve body 3. The valve body 3 bends with the support portion of the lower surface 3b of the valve body 3 supported by the valve seat 8 as a fulcrum, and the inner periphery of the upper surface 3a of the valve body 3 is provided away from the spring washer 4 on the outer periphery of the annular member 9. Port 2 is opened through the notch 9a.

  On the other hand, when the shock absorber is compressed, the hydraulic oil tends to pass through the port 2 upward in FIG. 1, so that the pressure from the lower chamber 42 side acts on the lower surface 3 b of the valve body 3. Then, the valve body 3 bends with a support portion by the spring washer 4 on the upper surface 3a of the valve body 3 as a fulcrum, and the outer periphery of the lower surface 3b of the valve body 3 is separated from the valve seat 8 to open the port 2.

  In the case of this valve structure, when the valve body 3 is opened inward and the port 2 is opened, the port 2 is opened by communicating with the upper chamber 41 through the notch 9a of the annular member 9. Therefore, the minimum flow path area when the hydraulic oil passes through the port 2 when the shock absorber extends is the area of the notch 9a that the inner periphery of the valve body 3 bends and faces the upper chamber 41. Therefore, the area of the notch 9a facing the upper chamber 41 is determined by the degree of opening of the notch 9a with respect to the amount of deflection on the inner peripheral side of the valve body 3, and the degree of opening of the notch 9a is shown in FIG. It is possible to change by setting the thickness of the middle and upper and lower. That is, the adjustment washer 10 is provided to adjust the degree of opening of the notch 9a with respect to the amount of deflection on the inner peripheral side of the valve body 3, and this adjustment can adjust the damping force when the shock absorber is extended. However, if it is not necessary, it can be omitted.

  Thus, in this valve structure, what is supported by the spring washer 4 that is a spring element is the back pressure side surface on the inner periphery that serves as a bending fulcrum when the valve body 3 opens outwardly and opens the port 2. Therefore, the back pressure side surface becomes the upper surface 3a of the valve body 3 that is the back surface of the lower surface 3b that acts as a pressure acting side when high pressure is applied to the outside, and therefore, in this valve structure, as described above, the upper surface 3a of the valve body 3 The inner periphery is supported by a spring washer 4.

  The annular member 9, the adjustment washer 10, the valve body 3 and the spring washer 4 together with the spacers 20 and 21 and the valve stopper 22 are attached to the tip 5 a of the piston rod 5 like the piston 1. The above-mentioned members are fixed to the piston rod 5 together with the piston 1 by screwing the piston nut 23 into the screw portion 5 c provided at the tip 5 a of the piston rod 5 from the middle and lower side.

  In this way, the spring washer 4 is laminated on the piston 1 and the inner peripheral side which is one end side is fixed to the tip 5a of the piston rod 5 to be a fixed end, and the outer periphery which is a free end is the upper surface 3a of the valve body 3. Supports the inner circumference.

  Next, the operation of the valve structure in the embodiment will be described. As shown in FIG. 2, when the piston 1 moves upward in FIG. Since the pressure in the upper chamber 41 is increased and the hydraulic oil in the upper chamber 41 tries to move through the port 2 in one direction, which is the lower direction in FIG. Due to the pressure on the upper chamber 41 side acting on the upper surface 3a, the port 2 is opened by bending with the support portion by the valve seat 8 on the lower surface 3b as a fulcrum.

  Conversely, as shown in FIG. 3, when the piston 1 moves downward in FIG. 3 with respect to the cylinder 40 and the shock absorber is compressed, the pressure in the lower chamber 42 increases, Since the hydraulic oil passes through the port 2 in the other direction which is the upward direction in FIG. 3 and tries to move into the upper chamber 41, the valve body 3 is caused by the pressure on the lower chamber 42 side acting on the lower surface 3b. The port 2 is opened by bending the support portion of the upper surface 3a by the spring washer 4 as a fulcrum, but the spring washer 4 as a spring element supports the inner periphery of the upper surface 3a of the valve element 3 on the free end side. Therefore, as shown in FIG. 3, the spring washer 4 also has an outer periphery that is a free end bent upward in FIG.

  That is, in the case of the valve structure applied to this shock absorber, when the shock absorber is compressed, both the spring washer 4 and the valve body 3 are bent to open the port 2.

  That is, only the valve body 3 is bent to open the port 2 when the shock absorber is extended, but the spring washer 4 and the valve body 3 are bent when the shock absorber is compressed, so that the shock absorber is extended and compressed. If the pressure difference between the upper chamber 41 and the lower chamber 42 is the same, the area of the flow path when opening the port 2 is increased by the amount of bending of the spring washer 4 when the shock absorber is compressed compared to when the buffer is expanded.

  Therefore, even in a valve structure that provides resistance to bidirectional movement of hydraulic fluid that passes through the port 2 with a single valve body 3, the hydraulic fluid flow depends on the setting of the bending stiffness that is the spring stiffness in the spring washer 4. Can be arbitrarily set according to the passage direction of the hydraulic oil through the port 2.

  In the present embodiment, the lower the bending rigidity of the spring washer 4 is set, the lower the combined bending rigidity of the valve body 3 and the spring washer 4, so that the valve structure is operated during the expansion stroke of the shock absorber. With respect to the resistance given to the oil flow, the resistance given to the hydraulic oil flow in the valve structure during the compression stroke of the shock absorber can be reduced, and the difference in resistance can be increased.

  In addition, when this valve structure is embodied in a shock absorber, the damping force in both strokes can be set arbitrarily. For example, a large difference can be given to the damping force in both strokes. In addition, since it is possible to exhibit a damping force suitable for the vehicle in the both strokes, it is possible to improve the riding comfort in the vehicle.

  In the valve structure described above, the spring element supports the back pressure side surface on the inner periphery that serves as a bending fulcrum when the valve body 3 opens and the port 2 is opened. Like the valve structure in one modification of the embodiment, the back pressure side surface of the outer periphery can be a bending fulcrum when the valve body 3 is opened inward and the port 2 is opened.

  In the valve structure in this modified example, the piston 11 is not formed with a valve seat, but a spring washer 12 set so that the inner edge is on the outer peripheral side of the port 2 is laminated, and the valve body is attached to the spring washer 12. 3 are stacked.

  In this case, the back pressure side surface of the valve body 3 is the lower surface 3b of the valve body 3 which is the back surface of the upper surface 3a on which high pressure is applied when the valve is opened, and the outer periphery of the lower surface 3b which is the back pressure side surface is the spring washer 12. Since it is supported by the inner periphery, the support portion by the spring washer 12 becomes a bending fulcrum when the valve body 3 is opened inward and the port 2 is opened.

  On the other hand, the upper surface 3a serving as a back pressure side surface on the inner periphery that is a bending fulcrum when the valve body 3 is opened outward is supported by the washer 13, unlike the above-described embodiment. In this case, the washer 13 actually supports the upper surface 3a which is the back pressure side surface of the inner periphery of the valve body 3 in a rigid manner, although it does not have any bending at all, and has a high spring rigidity. The amount of flexure of the device does not affect the amount of opening of the port 2 under the usage environment of the structure.

  In the valve structure of one modified example configured as described above, when the hydraulic oil passes through the port 2 upward in FIG. 4, the inner peripheral side of the valve body 3 is supported by the washer 13 that hardly bends. Therefore, only the valve body 3 bends to open the port 2, but when the hydraulic oil passes through the port 2 downward in FIG. 4, the valve body 3 bends inward to open the port 2. In doing so, the spring washer 12 is bent together with the valve body 3 to open the port 2.

  Therefore, even in the valve structure in this modified example, the resistance given to the hydraulic oil flow is arbitrarily set according to the passing direction of the hydraulic oil port 2 by setting the flexural rigidity that is the spring rigidity in the spring washer 12. can do. In this embodiment, the lower the bending rigidity of the spring washer 12 is set, the lower the combined bending rigidity of the valve body 3 and the spring washer 12, so that the valve structure is operated during the compression stroke of the shock absorber. With respect to the resistance given to the oil flow, the resistance given to the hydraulic oil flow by the valve structure during the extension stroke of the shock absorber can be lowered, and the difference in resistance can be increased.

  In addition, when this valve structure is embodied in a shock absorber, the damping force in both strokes can be set arbitrarily. For example, a large difference can be given to the damping force in both strokes. In addition, since it is possible to exhibit a damping force suitable for the vehicle in the both strokes, it is possible to improve the riding comfort in the vehicle.

  Furthermore, when the washer 13 in the above-described valve structure is changed to a spring washer 14 as a spring element, as in the valve structure in another modification shown in FIG. When passing to the side, the inner peripheral side of the valve body 3 is supported by the washer 13 functioning as a spring element, so that the valve body 3 and the washer 13 bend to open the port 2 and operate the port 2. When the oil passes downward in FIG. 5, the valve body and the spring washer 12 are bent to open the port 2.

  That is, when the washer 13 is changed to the spring washer 14 in this way, the back pressure side surfaces on both the inner periphery and the outer periphery that are the fulcrums of the valve body 3 are supported by the spring elements. The outer periphery of the lower surface 3b, which is the back pressure side surface of the valve body 3 that opens inward, is supported by a spring washer 12, and the inner periphery of the upper surface 3a, which is the back pressure side surface of the valve body 3 that opens outward, is a washer as a spring element. 13 will be supported.

  When the washer 13 is changed to the spring washer 14, when the shock absorber is extended, the hydraulic oil moves from the upper chamber 41 to the lower chamber 42, so the port 2 is moved downward in FIG. Therefore, the opening degree of the port 2 depends on the combined bending rigidity of the valve body 3 and the spring washer 12, and when the shock absorber is compressed, it operates. Since the oil moves from the lower chamber 42 to the upper chamber 41 and passes through the port 2 upward in FIG. 5, the valve body 3 is opened outward, and the degree of opening of the port 2 is determined by the valve body 3 and the spring washer. 14 and the combined flexural rigidity.

  Therefore, even in the valve structure of the other modified example, the resistance given to the hydraulic oil flow is set according to the passing direction of the hydraulic oil port 2 by setting the flexural rigidity which is the spring rigidity in the spring washers 12 and 14. Can be set arbitrarily. In this embodiment, the greater the difference between the flexural rigidity of the spring washers 12 and 14, the greater the resistance and shock absorber that is given to the flow of hydraulic oil in the valve structure during the compression stroke of the shock absorber. The difference in resistance given to the flow of hydraulic oil by the valve structure during the extension stroke can be increased.

  In addition, when this valve structure is embodied in a shock absorber, the damping force in both strokes can be set arbitrarily. For example, a large difference can be given to the damping force in both strokes. In addition, since it is possible to exhibit a damping force suitable for the vehicle in the both strokes, it is possible to improve the riding comfort in the vehicle.

  In each of the above-described embodiments, the spring elements are the spring washers 4, 12, and 14. Therefore, the overall length of the piston portion is not increased, and the stroke length of the shock absorber can be easily secured and assembled. Although there is an advantage that processing is easy, it is natural that the spring element may be a coil spring, a disc spring, or a conical spring in addition to the spring washer. Moreover, in each embodiment mentioned above, when the shock absorber is extended, the valve body 3 opens inward, and when the shock absorber is compressed, the valve body 3 is set to open outward. On the contrary, the valve body 3 may be set to open outward when the shock absorber is extended, and may be set to open inward when the shock absorber is compressed.

  Furthermore, in the above description, the valve structure of the present invention is embodied in the piston portion of the shock absorber. However, the valve structure may be embodied in the base valve portion of the shock absorber, and fluid pressure devices other than the shock absorber. Of course, it is possible to embody the valve.

  This is the end of the description of each embodiment, but the scope of the present invention is not limited to the details shown or described.

It is a longitudinal cross-sectional view in the piston part of the shock absorber in which the valve structure in one embodiment was embodied. It is a longitudinal cross-sectional view in the piston part at the time of the expansion stroke of the shock absorber in which the valve structure in one embodiment was embodied. It is a longitudinal cross-sectional view in the piston part at the time of the compression stroke of the shock absorber in which the valve structure in one embodiment was embodied. It is a longitudinal cross-sectional view in the piston part of the shock absorber in which the valve structure in one modification of one embodiment was embodied. It is a longitudinal cross-sectional view in the piston part of the shock absorber in which the valve structure in other modifications of one embodiment was embodied.

Explanation of symbols

1, 11 Piston 2 as valve disc Port 3 Valve body 3a Upper surface 3b of valve body Lower surface 4, 12, 14 of valve body Spring washer 5 as spring element Piston rod 5a End of piston rod 5b Piston rod step 5c Piston rod Screw part 6 Insertion hole 7 Annular window 8 Valve seat 9a Notch 9 Annular member 10 Adjusting washer 13 Washer 20, 21 Spacer 22 Valve stopper 23 Piston nut 40 Cylinder 41 Upper chamber 42 Lower chamber

Claims (3)

A valve disk in which a port is formed, and an annular valve body that is open at both the inner and outer peripheries to open and close the port, and the valve body opens inward when the fluid passes through the port in one direction. In a valve structure that is set to open and to open the port when the fluid passes through the port in the other direction, the back of the valve body on one or both of the inner and outer circumferences that serve as the bending fulcrum of the valve body A valve structure characterized in that the pressure side is supported by a spring element. 2. The valve structure according to claim 1, wherein the spring element is a spring washer whose one end is a fixed end and supports the back pressure side surface of the valve body on the free end. The valve disc is a piston in which a piston rod is inserted into an axial center portion, and the inner peripheral side of the spring washer is fixed to the piston rod to be a fixed end, and the back pressure side surface of the valve body is supported on the outer peripheral side. The valve structure according to claim 1 or 2.

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