JP2011064285A - Valve structure - Google Patents

Abstract

An object of the present invention is to provide a valve structure capable of improving the assemblability, and to provide a valve structure capable of preventing the occurrence of a defective assembly.
In order to solve the above-described object, the problem-solving means in the present invention includes a valve disk 1 in which a port 2 is formed, a shaft member 5a rising from an axial center portion of the valve disk 1, and an annular shape. An annular leaf valve 10 mounted on the outer periphery of the shaft member 5a and stacked on the valve disk 1 to open and close the port 2, and an annular leaf valve 10 mounted on the outer periphery of the shaft member 5a and stacked on the leaf valve 10. A guide member having a guide member 11 having a smaller diameter than the leaf valve 10 and an annular spring member 12 that is attached to the outer periphery of the guide member 11 and biases the leaf valve 10 toward the valve disc 1 side. 11 and the leaf valve 10 are integrated.
[Selection] Figure 1

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 an annular leaf valve is stacked on an outlet end of a port provided in the piston portion. Those that open and close ports are known.

  In particular, in the above valve structure in which the port is opened and closed by the leaf valve by fixing and supporting the inner periphery of the leaf valve and bending the outer periphery, the damping force in the low speed region is reduced when the leaf valve deflection rigidity is reduced. On the other hand, if the flexural rigidity is increased, the damping force in the medium / high speed region becomes too large, and it is difficult to satisfy the riding comfort in the vehicle in all speed regions.

  Therefore, in order to solve this problem, the inner peripheral side of the leaf valve is fixed by a guide member laminated on the leaf valve, and is slidably mounted on the outer periphery of the guide member by a disc spring mounted on the outer periphery of the guide member. A valve structure has been proposed in which a leaf valve is urged toward a piston through a valve holding member. In the illustrated case, the valve structure is embodied in a damping valve on both sides of the pressure expansion of a shock absorber (for example, Patent Document 1).

  In the shock absorber to which this valve structure is applied, when the piston speed when the piston moves is in a low speed region, the damping structure exhibits substantially the same damping characteristics as the valve structure in which the inner periphery is fixedly supported. When the speed reaches the middle to high speed range, the hydraulic oil pressure that passes through the port acts on the leaf valve, the leaf valve bends greatly against the urging force of the disc spring, and the port can be opened greatly, and the damping force is excessive. The ride comfort in the vehicle can be improved.

JP 2003-254375 A (FIG. 1)

  When actually assembling the valve structure as described above, an assembling apparatus as disclosed in Japanese Patent Application Laid-Open No. 2006-959 is used. Specifically, the assembling apparatus includes a holding needle, and a leaf valve, a guide member, a valve holding member, and a disc spring are once assembled with the holding needle together with a piston, and the piston, leaf valve, guide member, valve holding member, and plate are assembled. The valve structure is assembled by pulling out the spring from the holding needle, moving it to the outer periphery of the piston rod, and mounting it.

  However, when using the assembly method as described above, the leaf valve, the guide member, the valve holding member, and the disc spring are independent parts, and the axes of these parts are aligned with each other by the folding angle holding needle. However, when moving to the tip of the piston rod, each part may be scattered and the assembly may not be performed easily.

  Also, since the inner diameter of the valve restraining member is larger than the outer diameter of the holding needle and piston rod so that it can be attached to the outer periphery of the guide member, if the wall of the valve restraining member is thin, When assembled, the inner periphery of the valve restraining member may be pinched between the leaf valve and the guide member. There is time and effort that must be done.

  Therefore, the present invention has been developed to improve the above-mentioned problems, and its object is to provide a valve structure that can improve the assemblability, and other objects. Is to provide a valve structure capable of preventing the occurrence of defective assembly.

  In order to solve the above-described object, the problem-solving means in the present invention includes a valve disk in which a port is formed, a shaft member rising from the axial center of the valve disk, and an annular shape that is mounted on the outer periphery of the shaft member. And an annular leaf valve that is stacked on the valve disc to open and close the port, an annular guide member that is mounted on the outer periphery of the shaft member and is smaller in diameter than the leaf valve that is stacked on the leaf valve, and an outer periphery of the guide member The guide member and the leaf valve are integrated with each other in a valve structure including an annular spring member that is attached to the ring spring and biases the leaf valve toward the valve disk side.

  According to the valve structure of the present invention, since the guide member laminated on the leaf valve is integrated, the guide member and the leaf valve are not separated, and the disc spring mounted on the outer periphery of the guide member is provided. Since the guide member and the leaf valve can be maintained in a positioned state, the assembly to the shaft member is facilitated, and the assemblability of the valve structure is improved.

  In addition, when assembling the valve structure, when a valve restraining member is mounted on the outer periphery of the guide member, the valve restraining member may not be sandwiched between the guide member and the leaf valve, resulting in poor assembly. This eliminates the need for confirmation work and reduces the work burden.

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 top view of the leaf valve and guide member in the valve | bulb structure in one Embodiment. It is the figure which showed the damping characteristic of the expansion | extension side of the buffer with which the valve structure in one Embodiment was embodied.

  The valve structure of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the valve structure in one embodiment is embodied as an expansion-side damping valve of a piston portion of a shock absorber, and includes a piston 1 that is a valve disk in which a port 2 is formed, and a shaft of the piston 1. A tip 5a of a piston rod 5 as a shaft member rising from the center, an annular leaf valve 10 which is annular and mounted on the outer periphery of the tip 5a and is stacked on the piston 1 to open and close the port 2; The guide member 11 is mounted on the outer periphery of the tip 5a and has a smaller diameter than the leaf valve 10 stacked on the leaf valve 10, and is mounted on the outer periphery of the guide member 11 so that the leaf valve 10 faces the piston 1 side. A disc spring 12 as an annular spring member to be urged, and a disc spring 12 and a leaf valve are slidably mounted on the outer periphery of the guide member 11. It is configured to include 10 an annular valve restraining member 13, which is interposed between the.

  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 that slidably passes through a head member (not shown), a piston 1 that is inserted into the tip 5a of the piston rod 5 that forms a shaft member, and is fixed to the tip 5a, and a cylinder 40 An upper chamber 41 in FIG. 1, a lower chamber 42 in the lower side in FIG. 1, a sealing member (not shown) that seals the lower end of the cylinder 40, and the cylinder 40 protrude from the cylinder 40. A cylinder or an air chamber (not shown) that compensates for a change in the cylinder volume corresponding to the volume of the piston rod 5 is provided, and the cylinder 40 is filled with a fluid, specifically, hydraulic oil.

  In this case, in this case, when the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the pressure in the one chamber 41 rises and the port from the one chamber 41 to the other chamber 42 is ported. As a damping force generating element for generating a predetermined damping force in the shock absorber by causing the leaf valve 10 to resist the movement of the hydraulic oil when the hydraulic oil moves through 2 and causing a predetermined pressure loss. It is functioning.

  Hereinafter, the valve structure will be described in detail. The piston 1 serving as a valve disk is formed in a bottomed cylindrical shape, and an insertion hole 1b through which the tip 5a of the piston rod 5 of the shock absorber is inserted into the axial center of the bottom 1a; A port 2, a window 3 communicating with the port 2, an annular valve seat 1c formed on the outer peripheral side of the window 3 serving as an outlet end of the port 2 and projecting from the bottom 1a of the piston 1 toward the leaf valve 10; It is comprised including the cylinder part 1e extended in this.

  The piston 1 is provided with a pressure-side port 1d that allows a flow of hydraulic oil from the other chamber 42 to the one chamber 41 when the shock absorber contracts, on the outer peripheral side of the port 2 on the extended side of the bottom 1a. It has been.

  Further, as described above, by making the piston 1 into a cylindrical shape with a bottom, the leaf valve 10 and the like can be secured while ensuring the sliding contact length in the axial direction necessary for avoiding the shaft shake with respect to the cylinder 40. Part or all of the members constituting the valve structure can be accommodated in the piston 1, and the length from the upper end in FIG. 1 of the piston 1 to the lower end in FIG. 1 of the piston nut 6 can be shortened. There is an advantage that the piston part can be downsized.

  The piston rod 5 is inserted into the insertion hole 1b of the piston 1 as described above, and the tip of the piston rod 5 is projected downward in FIG. 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.

  Then, after inserting the tip 5a of the piston rod 5 into the inner circumference of the check valve 20, the spacer 21 and the valve stopper 22 on the pressure side, and the insertion hole 1b of the piston 1, respectively, the piston 1 is inserted into the tip 5a. After assembling the annular leaf valve 10, the guide member 11, the valve holding member 13, and the disc spring 12 disposed below in FIG. 1, the piston nut 6 is screwed onto the screw portion 5 c provided at the tip 5 a of the piston rod 5. By doing so, the piston 1 and each of the above members are sandwiched between the step portion 5 b of the piston rod 5 and the piston nut 6 and fixed to the piston rod 5.

  In the case of this embodiment, the suction side end, which is the lower end of the port 1d, is arranged so as not to be blocked by the leaf valve 10 disposed on the outer peripheral side from the opening end of the port 2 and stacked on the piston 1. The suction side end, which is the upper end of the port 2, is not blocked by a hole 20 a provided in the check valve 20. If the port 2 is not closed by the check valve 20 and the port 1d is not closed by the leaf valve 10, the arrangement and shape of the port 2 are not limited to those shown in the figure. You may employ | adopt the structure which arrange | positions on top and makes a valve seat what is called a petal type.

  A leaf valve 10 is stacked on the bottom 1 a of the piston 1. The leaf valve 10 is annular and is mounted on the outer periphery of the tip 5 a of the piston rod 5, and the inner peripheral side is sandwiched between the piston 1 and the piston nut 6. The outer periphery is a free end and the outer periphery is allowed to be bent.

  The leaf valve 10 can close the port 2 of the piston 1 by bringing the upper surface in FIG. 1 into contact with the valve seat 1c. In this embodiment, the leaf valve 10 is configured by a single annular plate, but may be configured as a laminated leaf valve by laminating a plurality of annular plates. Depending on the damping characteristics (relationship of the damping force to the piston speed) realized with this valve structure, it may be arbitrary depending on the damping characteristics generated by the shock absorber. When the annular plates are stacked, the outer diameter of each annular plate can be set differently depending on the attenuation characteristics generated in the shock absorber.

  As shown in FIGS. 1 and 2, the guide member 11 has an outer diameter smaller than the outer diameter of the leaf valve 10, is integrated with the leaf valve 10 in a concentric state, and is mounted on the outer periphery. The disc spring 12 and the valve holding member 13 are provided with an axial length sufficient to secure an interposing space. The guide member 11 and the leaf valve 10 are integrated by welding or bonding. In this integration, as will be described later, a disc spring 12 and a valve restraining member 13 mounted on the outer periphery of the guide member 11 are positioned on the guide member 11 and the leaf valve 10 to avoid an assembly failure. After the assembly is completed, these members are fastened and fixed by the piston nut 6 so that no positional deviation occurs after the assembly. 11 and the leaf valve 10 need only be prevented from separating, and may be temporarily fixed.

  On the outer periphery of the guide member 11, a valve holding member 13 that is annular and is laminated on the leaf valve 10 is slidably mounted. Further, a disc spring 12 as a spring member that is annular and is mounted on the outer periphery of the guide member 11 and positioned in the radial direction is provided below the valve holding member 13 in FIG. Shows the piston nut 6 and the leaf in the compressed state in the axial direction which is the vertical direction, with the outer peripheral side which is the upper end in the figure facing the leaf valve 10 side and the inner periphery which is the lower end in the figure is in contact with the piston nut 6 It is interposed between the valve 10 and urges the leaf valve 10 toward the piston 1. The biasing force of the disc spring 12 can be adjusted by the axial length of the guide member 11, the axial length of the valve holding member 13, and the number of interposed members.

  In the case of this embodiment, the urging force adjusting washer 14 is laminated on the valve holding member 13, and the washer 14 is also slidably mounted on the outer periphery of the guide member 11. The biasing force of the disc spring 12 can be adjusted by the axial length. The washer 14 can be omitted.

  The leaf valve 10 includes a plurality of notches 10a provided from the outer edge toward the inner periphery, and as shown in FIG. 2, seven of the notches 10a are provided. It is not limited. The outer diameter of the valve restraining member 13 is set to be equal to or larger than the outer diameter of the valve seat 1c. The notch 10a is formed by the valve restraining member 13 stacked below the leaf valve 10 in FIG. The orifice is formed with the leaf valve 10 seated on the valve seat 1c.

  In the case where the leaf valve 10 is a laminated leaf valve formed by laminating a plurality of annular plates, only the annular plate laminated on the piston 1 is provided with a notch that functions as an orifice as described above, and is counted from the piston 1 side. No cutout is provided in the annular plates after the first sheet. Further, instead of providing the notch 10a in the leaf valve 10, an orifice formed by being stamped on the valve seat 1c may be provided.

  Next, the operation of the valve structure in the embodiment will be described. As described above, when the piston 1 moves upward in FIG. 1 with respect to the cylinder 40, the pressure in the one chamber 41 increases, and the one chamber 41 increases. The hydraulic fluid inside passes through the port 2 and tries to move into the other chamber 42.

  When the piston speed, which is the expansion / contraction speed of the shock absorber, is in the low speed region, the leaf valve 10 cannot bend the outer periphery against the urging force of the disc spring 12, and the leaf valve 10 is attached by the disc spring 12. As a result, the hydraulic oil passes through the orifice formed by the notch 10a provided in the leaf valve 10 seated on the valve seat 1c.

  Therefore, the damping characteristic (relationship of the damping force to the piston speed) at this time is as shown by the solid line in FIG. 3, and the damping coefficient is relatively large in this low speed region.

  On the other hand, the speed of the piston 1 reaches the middle-high speed region, the difference between the pressure in the one chamber 41 and the pressure in the other chamber 42 increases, and the force for pushing down the leaf valve 10 of the hydraulic oil downward in FIG. Thus, the force overcomes the biasing force of the disc spring 12, and the outer periphery of the leaf valve 10 is bent.

  As described above, when the leaf valve 10 is bent, a gap between the valve seat 1c and the leaf valve 10 is generated to greatly open the port 2, and the gap is increased in proportion to the piston speed. In other words, the damping characteristic when the piston speed is in the medium-high speed region is as shown by the solid line in FIG. 3 and is proportional to the increase in piston speed, but the damping coefficient is smaller than the low speed region, and the slope of the damping characteristic Becomes smaller.

  Therefore, in the valve structure in one embodiment, the disc spring 12 is used instead of the coil spring to bias the leaf valve 10, and the axial length can be shorter than that of the coil spring. Since the amount of bending of 10 can be ensured, the damping coefficient when the piston speed is in the medium to high speed region can be reduced, and there is no possibility that the riding comfort in the vehicle is impaired.

  In the valve structure according to the present embodiment, since the guide member 11 laminated on the leaf valve 10 is integrated, the guide member 11 and the leaf valve 10 do not vary, and the guide member 11 can be maintained in a state where the disc spring 12 and the valve restraining member 13 mounted on the outer periphery of the guide member 11 are positioned on the guide member 11 and the leaf valve 10, so that the assembly to the tip 5a of the piston rod 5 as the shaft member becomes easy. The assembly of the structure is improved.

  Further, when assembling the valve structure, the valve holding member 13 is not sandwiched between the guide member 11 and the leaf valve 10, and no assembly failure occurs, so that a confirmation work is unnecessary and the work load is reduced. Is reduced.

  In the present embodiment, in order to explain the change of the damping characteristic, the piston speed is provided with the sections of low speed and medium speed, but the speed of the boundary between these sections can be set arbitrarily. it can.

  In addition to the disc spring 12, the spring member may be an elastic body such as a wave washer or rubber, and the shaft member is the tip 5a of the piston rod 5 as described above. It is good also as a structure provided in a valve disc.

  This is the end of the description of the embodiment of the valve structure, but the valve structure of the present invention can be embodied in the compression side damping valve of the piston portion of the shock absorber, or in the base valve portion. Thus, the effects of the present invention are not lost.

  It should be noted that the scope of the present invention is not limited to the details shown or described.

The present invention is applicable to a valve such as a shock absorber.

DESCRIPTION OF SYMBOLS 1 Piston 1a which is a valve disc Bottom 1b Insertion hole 1c Valve seat 1d, 2 Port 1e Tube part 3 Window 5 Piston rod 5a Piston rod tip 5b Step part 5c Screw part 6 Piston nut 10 Leaf valve 10a Notch 11 Guide Member 12 Disc spring 13 as a spring member Valve restraining member 14 Washer 20 Check valve 20a Hole 21 Spacer 22 Valve stopper 40 Cylinder 41 One chamber 42 Other chamber

Claims (2)

A valve disk in which a port is formed, a shaft member rising from an axial center portion of the valve disk, an annular leaf valve which is annular and mounted on the outer periphery of the shaft member and is stacked on the valve disk to open and close the port A ring-shaped guide member that is mounted on the outer periphery of the shaft member and is smaller in diameter than the leaf valve stacked on the leaf valve; and an annular shape that is mounted on the outer periphery of the guide member and urges the leaf valve toward the valve disk side. In the valve structure comprising the spring member of the above and the annular valve restraining member that is slidably mounted on the outer periphery of the guide member and interposed between the spring member and the leaf valve, the guide member and the leaf valve are Valve structure characterized by integration. The valve structure according to claim 1, wherein the guide member and the leaf valve are integrated by welding or adhesion.

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