JP5466539B2 - Damping valve - Google Patents

Description

  The present invention relates to an improved damping valve.

  Conventionally, in this type of damping valve, for example, an annular valve is provided in the middle of a passage communicating two pressure chambers provided inside a shock absorber interposed between a bogie and a vehicle body of a railway vehicle. A piston having a valve hole with a seat; a valve body that can be freely attached to and detached from the annular valve seat; and that is accommodated in the valve hole; a spring seat stacked on the piston; and the valve body and the spring seat. There are known ones that are configured to include a coil spring that is interposed and biases the valve body toward the annular valve seat (see, for example, Patent Document 1).

  When the pressure valve receives pressure from the spring seat side against the valve hole, the valve body sits on the annular valve seat and closes the valve hole. Conversely, when pressure is received from the annular valve seat side, the valve body The valve is retreated from the annular valve seat to open the valve hole and allow fluid flow. More specifically, when the shock absorber is activated and the annular valve seat side of the valve hole faces the pressure chamber on the compression side, the valve body is opened by being pushed into the valve hole by the pressure in the rising pressure chamber. It comes to speak. When the damping valve is opened, the fluid that has entered the valve hole moves into the pressure chamber on the expansion side via a communication groove provided in the piston.

  In addition, as the pressure chamber on the compression side rises, the retraction amount in which the valve body retreats away from the annular valve seat increases, and the valve opening area limited by the valve body and the annular valve seat increases as the retraction amount increases. However, when the valve body is retracted from the annular valve seat by a predetermined amount of retraction, the valve opening area limited by the valve body and the annular valve seat becomes greater than the flow passage area in the communication groove, The channel area does not change with respect to the backward movement.

  Furthermore, the spring seat is not stacked on the piston, but is screwed into a valve hole provided in the piston (see, for example, Patent Document 2). When the annular valve seat side of the valve hole faces the compression-side pressure chamber, the valve body is opened by being pushed into the valve hole by the pressure in the rising pressure chamber, and the compression-side pressure chamber rises. Accordingly, the retraction amount in which the valve body retreats away from the annular valve seat increases, and the valve opening area limited by the valve body and the annular valve seat increases as the retraction amount increases, but the valve body is determined in advance. When the retracted amount is retracted from the annular valve seat, the valve opening area limited by the valve body and the annular valve seat becomes larger than the flow passage area in the through hole provided in the spring seat, As a result, the flow path area does not change.

  Further, the shock absorber provided with the damping valve includes a constant orifice arranged in parallel with the damping valve. Such a shock absorber exhibits a damping force that rises relatively abruptly, which is a square characteristic by a constant orifice when the expansion / contraction speed is extremely low, and attenuates when the expansion / contraction speed exceeds the low speed range and becomes a high speed range. The valve opens and the valve opening area expands as the expansion speed increases, so a damping force with a relatively small damping coefficient is output as the expansion speed increases, and the expansion speed becomes ultra-high. If the flow path area does not increase even when the valve body is retracted, a damping force having a relatively large damping coefficient will be exhibited.

JP 2007-71233 A JP 2007-71232 A

  By the way, in particular, in a shock absorber provided for the purpose of suppressing lateral vibrations of a bogie and a vehicle body in a railway vehicle, mainly vehicle body vibrations caused by an input of disturbance in a track error, a cross wind, a tunnel traveling, etc. In recent years, there has been a demand for suppression for the purpose of improving ride comfort. However, in recent years, when the vehicle body vibrates due to a strong earthquake or the like that occurs while the vehicle is running, the vehicle body vibration is effectively exerted with a large damping force. It has come to be required to suppress.

  In order to satisfy this requirement, it is necessary for the shock absorber to exert a large damping force when the expansion / contraction speed of the shock absorber exceeds the high speed region and reaches the ultra high speed region. In order to realize the damping force characteristics that meet this requirement, the valve opening area limited by the valve body and the annular valve seat must be greater than the flow passage area in the communication groove or through hole when the expansion / contraction speed becomes extremely high. However, there is a processing error even if the components that make up the damping valve are processed with high accuracy, and there is also an error caused by assembly to the piston, etc., and the damping force characteristics that require the damping force characteristics of the shock absorber There is a possibility that it will come off.

  In addition, the conventional damping valve does not employ a structure for adjusting the damping force characteristic, and the damping force adjustment involves substantial replacement of parts. Therefore, after the conventional damping valve is assembled to the shock absorber, Since the damping force characteristic cannot be adjusted, the damping force characteristic cannot be tuned.

  Therefore, the present invention has been developed to improve the above-described problems, and the object of the present invention is to tune the damping force characteristics after the assembly to the shock absorber, so that the vehicle of the railway vehicle can be tuned. The present invention is to provide a damping valve that is suitable for a shock absorber for system vibration use, and that can cause the shock absorber to exhibit an optimum damping force characteristic for suppressing vibration of a vehicle body of a railway vehicle.

In order to achieve the above-described object, the problem-solving means in the present invention includes a housing having a valve hole provided with an annular valve seat, and a valve body that is movably accommodated in the valve hole and seats on and off the annular valve seat. A damping valve mounted on a shock absorber, comprising: a spring seat fixed in the valve hole; and a spring interposed between the valve body and the spring seat to urge the valve body toward the annular valve seat in includes a spring seat body is screwed into the spring locus valve hole, and a regulating member which is movably held in the spring seat body while being arranged in the valve bore in the axial direction, the spring seat body is the spring The restricting member is provided with a head portion that faces the spring receiving portion and is brought into contact with the spring receiving portion, and when the retraction amount of the valve body from the annular valve seat becomes a predetermined amount, the restricting member It is characterized by restricting further retreat from the annular valve seat of the valve body by abutting against the valve body.

The shock absorber equipped with the damping valve of the present invention exerts an appropriate damping force when it is interposed between the body of the railway vehicle and the bogie, particularly in a situation where a large earthquake has not occurred. Suppresses vehicle body vibration while driving to ensure ride comfort in the vehicle, and suppresses vehicle body vibration of railway vehicles by exhibiting a greater damping force in situations where an earthquake occurs during vehicle driving and vehicle body vibration increases. Therefore, vehicle body vibration can be effectively suppressed.

  The damping valve regulates the backward movement of the valve body by abutting a regulating member, which is movable in the axial direction with respect to the spring seat body in the spring seat, to the valve body. Can be adjusted, the maximum valve opening area restricted by the valve body and the annular valve seat can be adjusted, and the inflection on the damping force characteristic that the damping coefficient becomes large The point can also be adjusted.

  In addition, since the above adjustment is possible with the damping valve assembled to the shock absorber piston, etc., the processing error of the members constituting the damping valve and the assembly when the damping valve is assembled to the shock absorber piston, etc. Even if there is an error, the damping force characteristics of the shock absorber can be set as intended by adjusting the abutting position between the restricting member and the valve body, and the shock absorber is optimized to suppress vehicle vibration. It is possible to tune the damping force characteristics of the vessel.

  In addition, the spring seat body that supports one end of the spring can be fixed with respect to the valve hole even if the abutting position between the valve body and the regulating member is changed. Since the initial load applied can be adjusted independently, the damping force characteristic of the damping valve can be changed with a high degree of freedom.

  Further, the tuning is performed by a regulating member that is movable in the axial direction with respect to the spring seat body, and since these are all accommodated in the valve hole, the member used for tuning is not provided elsewhere. It can be mounted without difficulty in a shock absorber with a small space for installing a damping valve, such as a shock absorber with a small cylinder diameter and a limited space for mounting a damping valve on a piston or rod guide. it can.

It is a longitudinal cross-sectional view of the damping valve in one embodiment. It is the schematic of the shock absorber for the vehicle system vibration of a railway vehicle to which the damping valve of one embodiment is applied. It is a top view of the damping valve in one embodiment. It is the figure which showed the damping force characteristic of the shock absorber for vehicle system vibration to which the damping valve of one embodiment was applied.

  Hereinafter, the damping valve 1 of this invention is demonstrated based on figures. As shown in FIG. 1, the damping valve 1 in one embodiment is accommodated in a piston 2 as a housing having valve holes 2a and 2b having an annular valve seat 4, and in the valve holes 2a and 2b. The valve body 5 that is attached to and detached from the annular valve seat 4, the spring seat 10 that is fixed in the valve holes 2 a and 2 b, and the valve body 5 is interposed between the valve body 5 and the spring seat 10. And a coil spring 14 as a spring biased toward the seat 4.

  The damping valve 1 is embodied in a shock absorber D as shown in FIG. The shock absorber D is particularly used for the purpose of suppressing the vehicle body vibration in the lateral direction with respect to the traveling direction of the railway vehicle by being interposed between the vehicle body B and the carriage W of the railway vehicle. The shock absorber D includes a cylinder 21, a piston 2 that is slidably inserted into the cylinder 21, and that defines two pressure chambers R <b> 1 and R <b> 2 that are filled with a fluid such as hydraulic oil, and the cylinder 21. A piston rod 22 that is movably inserted into the piston 21 and connected to the piston 2, an outer cylinder 23 that covers the outer periphery of the cylinder 21 and forms a reservoir R between the cylinder 21, and the cylinder 21 and the outer cylinder 23. A rod guide 24 that closes the end portion and pivotally supports the piston rod 22 and a lid 25 that closes the other end of the cylinder 21 and the outer cylinder 23 are provided. In this case, the shock absorber D is a single piece. Lo There is a type of damper. Of course, a double rod type shock absorber may be used.

  The piston 2 is provided with valve holes 2a and 2b, and the damping valve 1 is installed with the piston 2 as a housing, and the valve bodies 5 are accommodated in the valve holes 2a and 2b with the directions of the valve bodies 5 being alternately arranged. Has been. In the shock absorber D, when the piston 2 tries to move to the left in FIG. 2, the pressure in the pressure chamber R1 on the left in the figure rises, and the pressure on the valve hole 2a side is increased by the pressure. When the damping valve 1 is opened, the damping valve 1 exerts a damping force by giving resistance to the liquid flow while allowing the fluid in the pressure chamber R1 to escape to the right pressure chamber R2 in the figure through the valve hole 2a. To do. In addition, the damping valve 1 on the valve hole 2b side receives the pressure of the pressure chamber R1 and remains closed to block the valve hole 2b. On the other hand, when the piston 2 tries to move to the right in FIG. 2, the pressure in the right pressure chamber R2 in the figure rises, and the damping valve 1 on the valve hole 2b side opens by the pressure, The damping valve 1 exerts a damping force by giving resistance to the flow of liquid while allowing the fluid in the pressure chamber R2 to escape to the left pressure chamber R1 in the drawing through the valve hole 2b. In addition, the damping valve 1 on the valve hole 2a side receives the pressure of the pressure chamber R2 and remains closed to block the valve hole 2a.

  Thus, the damping valve 1 acts as a damping valve that causes the shock absorber D to exert a damping force when vibration is input to the shock absorber D. In the case of the shock absorber D, the volume of fluid in which the piston rod 22 enters and exits the cylinder 21 is compensated by supplying and discharging the fluid from the reservoir R through the passages 25a and 25b provided in the lid 25. In particular, during the stroke in which the piston rod 22 enters the cylinder 21, the damping valve 26 provided in the middle of the passage 25a is opened and the fluid is discharged from the pressure chamber R2 to the reservoir R. Thus, a resistance is given to the flow of the fluid to increase the internal pressure in the cylinder 21, and a damping force is exhibited in cooperation with the damping valve 1 on the valve hole 2b side. Note that the above-described configuration of the damping valve 1 can be adopted as the damping valve 26. On the other hand, in the process of retracting the piston rod 22 from the cylinder 21, the check valve 27 provided in the middle of the passage 25b is opened and the fluid is supplied from the reservoir R to the pressure chamber R2. Hardly gives resistance to the flow of the fluid.

  Further, the shock absorber D includes a constant orifice 28 that communicates the pressure chamber R1 and the pressure chamber R2 in parallel with the above-described damping valve 1, and the fluid is kept constant until the damping valve 1 is opened. 28, the pressure chambers R1 and R2 are moved back and forth. The constant orifice 28 is provided in the piston 2, but may be provided in the rod guide 24, the cylinder 21, and the lid 25.

  The configuration of the shock absorber D is not limited to the above. For example, the reservoir R, the pressure chamber R1, the pressure chamber R2, and the reservoir R of the shock absorber D are connected in a passage through a passage, and the shock absorber D is expanded and contracted. In the case of a uniflow shock absorber in which fluid is circulated in the order of the reservoir R, the pressure chamber R2, the pressure chamber R1, and the reservoir R, a valve hole for communicating the pressure chamber R1 and the reservoir R with the rod guide 24 as a housing is provided. The damping valve 1 may be provided so as to give resistance when the fluid flows from the pressure chamber R1 toward the reservoir R. Further, the damping valve 1 according to the present invention may be applied to the damping valve 26 provided on the lid 25. Further, the lid 25 is a member including a check valve 27 and a damping valve 26, assuming that only the outer cylinder 23 is closed. The inside of the cylinder 21 and the reservoir R may be partitioned.

  Hereafter, each part of the damping valve 1 will be described in detail below. The piston 2 as a housing is annular, and is provided with valve holes 2a and 2b in which the valve body 5 is accommodated. The damping valve 1 is installed in the piston 2 in opposite directions on the side of the valve holes 2a and 2b. However, since the structure is the same and the description is repeated, a specific structure will be described below with the valve hole 2a as an example. Will be described.

  As shown in FIG. 1, the inner periphery of the lower end in FIG. 1 of the valve hole 2 a is reduced in diameter to form a reduced diameter portion 3, and the annular valve seat 4 is formed by a step portion provided by the formation of the reduced diameter portion 3. Is formed. Further, a screw portion 9 is provided on the inner periphery of the upper end in FIG. 1 of the valve hole 2a, and a spring seat 10 is screwed to the screw portion 9.

  The valve body 5 is accommodated in the valve hole 2a so as to be movable in the axial direction, and is formed at a disc-shaped valve body 6 that is attached to and detached from the annular valve seat 4 and at the lower end in FIG. The cylindrical valve head 7 and a spring fitting portion 8 that protrudes toward the valve head side of the valve body 6 are provided. Further, the valve head 7 is slidably inserted into the reduced diameter portion 3 in the valve hole 2a, and the valve body 5 with the valve head 7 as a guide is not displaced by the reduced diameter portion 3 of the valve hole 2a. It can move in the direction. In addition, you may make it guide the movement of the valve body 5 by making the outer periphery of the valve main body 6 slidably contact with the inner peripheral surface of the valve hole 2a. A cutout or the like may be provided so as to allow passage of fluid.

  When the lower end of the valve body 6 in FIG. 1 is brought into contact with the upper surface of the annular valve seat 4 in FIG. 1 and is seated, the damping valve 1 is closed and the flow of fluid into the valve hole 2a is blocked. Can be done. Further, the valve head 7 is provided with a U-shaped groove 7a from the distal end to the proximal end, and the lower end of the valve body 6 in FIG. 1 is from the upper surface in FIG. When retreating to the inside of the hole 2a, the groove 7a opens from the reduced diameter portion 3 to the inside of the valve hole 2a according to the retraction amount, and the fluid flows into the valve hole 2a through the groove 7a. It can be done. And according to the retraction amount of the valve body 6 in this valve body 5, the area which the groove | channel 7a faces in the valve hole 2a becomes large, and the valve opening area increases. Note that the shape of the valve head 7 is not limited to the above, and in particular, the valve head 7 may not function as a guide for the movement of the valve body 5.

  A spring seat 10 is accommodated in the valve hole 2a in addition to the valve body 5. The spring seat 10 includes a spring seat body 11 screwed into the valve hole 2a, and a spring seat body 11. And a regulating member 12 that is held so as to be movable in the axial direction and regulates the backward movement of the valve body 5 from the annular valve seat 4.

  The spring seat body 11 includes a cylindrical spring fitting portion 11a and a spring receiving portion 11b provided on the outer periphery of the spring fitting portion 11a and screwed to the screw portion 9 of the valve hole 2a. The outer periphery of the receiving portion 11b is provided with chamfered portions 11c, 11c having a two-sided width, and as shown in FIG. 3, fluid is placed between the chamfered portions 11c, 11c of the spring seat body 11 and the valve hole 2a. Passages 13a and 13b that allow passage are provided.

The regulating member 12 includes a screw portion 12a that is screwed to the inner periphery of the spring fitting portion 11a, and a head portion 12b that is provided at the upper end of the screw portion 12a in FIG. 1, and the spring fitting portion 11a. A plurality of annular shims 15 are interposed between the upper end of the head and the head 12b. In this way, the restricting member 12 is held so as to be movable in the axial direction with respect to the spring seat main body 11 by being screwed to the spring fitting portion 11a, and is restricted by the number of shims 15 interposed. The lower end position in FIG. 1, which is the tip of the member 12, can be positioned in the axial direction with respect to the spring seat body 11. In addition, when it is not necessary to interpose the shim 15, this may be abolished and the head part 12b may be directly contacted with the spring receiving part 11b.

Further, a coil spring 14 is interposed between the spring receiving portion 11b and the valve body 5 in a compressed state . The spring receiving portion 11b supports the upper end of the coil spring 14, and the compressed coil spring 14 The urging force acts on the valve body 5 toward the annular valve seat 4.

  Therefore, in the damping valve 1 on the valve hole 2a side, the pressure in the pressure chamber R1 acts on the valve head 7 of the valve body 5, and the force pushing the valve body 5 biases the valve body 5 of the coil spring 14. When the force is exceeded, the valve is opened, and the fluid that has pushed the valve body 5 and passed through the groove 7a passes through the valve hole 2a and the passages 13a and 13b to the pressure chamber R2.

  As the pressure acting on the distal end side of the valve body 5 increases, the amount of retreat away from the annular valve seat 4 and inward of the valve hole 2a increases. As the retraction amount increases, the valve body 5 and the annular valve increase. The valve opening area limited by the seat 4 also increases. Then, when the valve body 5 moves backward, and the amount of the valve body 5 retracted from the annular valve seat 4 reaches a predetermined amount, the spring fitting portion 8 of the valve body 5 abuts against the tip of the regulating member 12. Thus, the movement of the valve body 5 in the direction away from the annular valve seat 4 is restricted. In other words, the valve body 5 is restricted from being further retracted from the annular valve seat 4 by the spring seat 10. Therefore, thereafter, the valve body 5 is prevented from retreating, so that even if the pressure in the pressure chamber R1 rises, the valve opening area does not increase. Further, since the restricting member 12 is movable in the axial direction with respect to the spring seat body 11, it is possible to adjust a predetermined retraction amount in which the retraction of the valve body 5 is restricted.

  On the other hand, in the damping valve 1 on the valve hole 2b side, the pressure in the pressure chamber R2 acts on the valve head 7 of the valve body 5, and the force pushing the valve body 5 biases the valve body 5 of the coil spring 14. When the force is exceeded, the valve is opened, and the fluid that has pushed the valve body 5 away and passed through the groove 7a passes through the valve hole 2b and the passages 13a and 13b to the pressure chamber R1.

  As the pressure acting on the distal end side of the valve body 5 increases, the amount of retreat away from the annular valve seat 4 and inward of the valve hole 2b increases. As the retraction amount increases, the valve body 5 and the annular valve increase. The valve opening area limited by the seat 4 also increases. Then, when the valve body 5 moves backward, and the amount of the valve body 5 retracted from the annular valve seat 4 reaches a predetermined amount, the spring fitting portion 8 of the valve body 5 abuts against the tip of the regulating member 12. Thus, the movement of the valve body 5 in the direction away from the annular valve seat 4 is restricted. In other words, the valve body 5 is restricted from being further retracted from the annular valve seat 4 by the spring seat 10. Therefore, thereafter, the valve body 5 is prevented from retreating, so that even if the pressure in the pressure chamber R2 increases, the valve opening area does not increase. Further, since the restricting member 12 is movable in the axial direction with respect to the spring seat body 11, it is possible to adjust a predetermined retraction amount in which the retraction of the valve body 5 is restricted.

  Next, the operation of the damping valve 1 will be described by taking as an example one installed in the valve hole 2a of the shock absorber D. In the damping valve 1 configured as described above, when the piston 2 has a leftward displacement input in FIG. 2, the pressure in the left pressure chamber R1 in the figure rises. However, since the valve does not open until the pressure reaches the valve opening pressure of the damping valve 1, the fluid moves from the pressure chamber R1 to the pressure chamber R2 only through the constant orifice 28. Therefore, the characteristic of the damping force with respect to the piston speed of the shock absorber D until the damping valve 1 is opened is a square characteristic peculiar to the orifice, as shown in the section A in FIG. On the other hand, it exhibits a damping force with a relatively high damping coefficient.

  When the moving speed of the piston 2 increases, the pressure in the left pressure chamber R1 in the figure increases and the pressure reaches the valve opening pressure of the damping valve 1, the valve body 5 is The coil spring 14 is compressed by being pressed by the pressure, retreats away from the annular valve seat 4 and opens the valve hole 2a. When the damping valve 1 is thus opened, the fluid in the left pressure chamber R1 to be compressed flows into the valve hole 2a and moves to the pressure chamber R2 through the passages 13a and 13b. The shock absorber D applies a resistance to the fluid flow by the damping valve 1 against the leftward movement of the piston 2 to generate a damping force that suppresses the movement of the piston 2. At this time, the resistance at the constant orifice 28 is larger than that of the damping valve 1, and the flow rate flowing through this is small, and the damping force characteristic of the shock absorber D is dominated by the characteristic of the damping valve 1.

  Then, the moving speed of the piston 2 to the left does not reach a predetermined moving speed, and the pressure in the pressure chamber R1 acting on the valve body 5 causes the valve body 5 to abut against the regulating member 12 in the spring seat 10. In the state in which the valve body 5 is not retracted to the maximum, the valve body 5 can be moved away from the annular valve seat 4 in accordance with the pressure increase in the pressure chamber R1 due to the increase in the piston speed, so that the valve opening area can be increased. As shown in the section B in FIG. 4, the damping force characteristic that increases the damping force with a relatively small inclination with respect to the increase in the piston speed is exhibited.

  In the damping valve 1, when the fluid passes between the valve body 5 and the annular valve seat 4, not only resistance is given to the flow of the fluid but also the fluid passes through the passages 13a and 13b. In this case, resistance is given to the flow of the fluid. Therefore, when the fluid that has passed between the valve body 5 and the annular valve seat 4 passes through the passages 13a and 13b, the pressure in the valve hole 2a rises, and this pressure is used as a secondary pressure. The valve element 5 can be urged toward the annular valve seat 4 side in the valve closing direction by acting on the upper surface side in FIG. Thus, the secondary pressure can be arbitrarily set according to the opening areas of the passages 13a and 13b. The opening areas of the passages 13a and 13b are characterized by the damping force characteristics of the shock absorber D after the damping valve 1 is opened. However, the secondary pressure may not be positively applied to the valve body 5 by ensuring a sufficiently large flow passage area of the passages 13a and 13b.

  Subsequently, the moving speed of the piston 2 to the left (the expansion / contraction speed of the shock absorber D) reaches a predetermined speed, the pressure in the pressure chamber R1 acting on the valve body 5 increases, and the valve body 5 is moved to the spring seat 10. When the valve is retracted until it is brought into contact with the restricting member 12, the valve body 5 is prevented from retreating away from the annular valve seat 4 no matter how much the pressure in the pressure chamber R <b> 1 increases due to the subsequent increase in the piston speed. Therefore, the valve opening area cannot be increased any further, and the shock absorber D increases the damping force with a relatively large inclination with respect to the increase in the piston speed as shown in the section C in FIG. Demonstrate force characteristics. Specifically, the square characteristic according to the opening area is obtained. That is, in the shock absorber D, the attenuation coefficient changes and the attenuation coefficient increases with the boundary between the section B and the section C as an inflection point. Note that the operation of the damping valve 1 installed in the valve hole 2b of the shock absorber D exhibits the same operation as described above when the movement direction of the piston 2 is opposite to the above, and a detailed description thereof will be omitted. To do.

  Thus, the shock absorber D equipped with the damping valve 1 exhibits a moderate damping force and suppresses vehicle body vibration during traveling of the railway vehicle, particularly in a situation where a large earthquake does not occur, so In the situation where an earthquake occurs while the vehicle is running and the vehicle body vibration becomes large, a greater damping force is exerted to suppress the vehicle body vibration of the railway vehicle. it can.

  The damping valve 1 regulates the backward movement of the valve body 5 by abutting a regulating member 12 that is movable in the axial direction with respect to the spring seat body 11 in the spring seat 10 to the valve body 5. Since the abutting position of the regulating member 12 and the valve body 5 with respect to the annular valve seat 4 can be adjusted, the maximum valve opening area regulated by the valve body 5 and the annular valve seat 4 can be adjusted, and the damping coefficient It is also possible to adjust the inflection point on the damping force characteristic where becomes larger.

  Further, since the above adjustment is possible with the damping valve 1 assembled to the piston of the shock absorber D, the processing error of the members constituting the damping valve 1 and the damping valve 1 to the piston of the shock absorber D, etc. Even if there is an assembly error at the time of assembly, the damping force characteristic of the shock absorber D can be set as intended by adjusting the abutting position between the regulating member 12 and the valve body 5, and the vehicle body vibration can be reduced. The damping force characteristic of the shock absorber D can be tuned so as to be optimal for suppression.

  In addition, the spring seat body 11 that supports one end of the coil spring 14 can be fixed with respect to the valve holes 2a and 2b even if the contact position between the valve body 5 and the regulating member 12 is changed. Since the tuning can be performed independently of the adjustment of the initial load applied to the valve body 5 by the coil spring 14, the damping force characteristic of the damping valve 1 can be changed with a high degree of freedom.

  Further, the tuning is performed by a regulating member 12 that is movable in the axial direction with respect to the spring seat body 11, and since these are all accommodated in the valve holes 2a and 2b, they are used for tuning. For example, a shock absorber having a small space for installing the damping valve 1 without interfering with other parts, such as a shock absorber having a small cylinder diameter and a limited space for mounting the damping valve 1 on a piston or rod guide. Can be installed without difficulty.

  Therefore, the damping valve 1 can cause the shock absorber D to exhibit an optimum damping force particularly for suppressing the vibration of the vehicle body of the railway vehicle, and is optimal for the shock absorber D for the vehicle system vibration use of the rail vehicle. Become.

  The predetermined speed of the shock absorber D when the restricting member 12 abuts the valve body 5 to restrict the retraction of the valve body 5 from the annular valve seat 4 can be arbitrarily set. Specifically, for example, it may be set to an expansion / contraction speed expected to be reached when the vehicle body vibrates due to a large earthquake. Further, when the predetermined speed is reached, the regulating member 12 may abut against the valve body 5 to regulate the backward movement of the valve body 5 from the annular valve seat 4. What is necessary is just to set according to a predetermined speed about the predetermined retraction amount at the time of abutting with the valve body 5. FIG.

Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to the details shown or described.

  The present invention can be used for a damping valve of a shock absorber.

DESCRIPTION OF SYMBOLS 1 Damping valve 2 Piston 2a, 2b as a housing Valve hole 3 Diameter reduction part 4 Annular valve seat 5 Valve body 6 Valve main body 7 Valve head 7a Groove 8 Spring fitting part 9 Screw part 10 Spring seat 11 Spring seat main body 11a Spring fitting Joint part 11b Spring receiving part 11c Chamfering part 12 Restriction member 12a Screw part 12b Head part 13a, 13b Passage 14 Coil spring 15 Shim 21 Cylinder 22 Piston rod 23 Outer cylinder 24 Rod guide 25 Lid 25a, 25b Passage 26 Damping valve 27 Check Valve 28 Constant orifice D Shock absorber B Body R Reservoir R1, R2 Pressure chamber W Dolly

Claims (3)

A housing having a valve hole with an annular valve seat, a valve body movably accommodated in the valve hole and seated on and off the annular valve seat, a spring seat fixed in the valve hole, a valve body and a spring seat A damping valve mounted on the shock absorber with a spring interposed between the spring seat and biasing the valve body toward the annular valve seat, and a spring seat body screwed into the valve hole; And a regulating member that is disposed in the valve hole and is held by the spring seat body so as to be movable in the axial direction. The spring seat body comprises a spring receiving portion that supports the spring, and the regulating member faces the spring receiving portion. When the retraction amount of the valve body from the annular valve seat reaches a predetermined amount, the regulating member abuts on the valve body and further from the annular valve seat of the valve body. A damping valve characterized by regulating the reverse movement of the valve. 2. The damping valve according to claim 1, wherein when the expansion / contraction speed of the shock absorber reaches a predetermined speed, the valve body collides with the restriction member to restrict the valve body from retreating from the annular valve seat. The damping valve according to claim 1 or 2, wherein a shim is interposed between the head and the spring receiving portion.

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