JP2007016880A - Valve structure of pneumatic shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the quietness of a pneumatic shock absorber by suppressing the generation of a blowing sound of a working gas.
SOLUTION: An annular leaf valve 10 that is stacked on a valve body 4 in which ports 1 and 2 are formed and opens and closes an outlet end of the ports 1 and 2, and an outer peripheral end deflection of the leaf valve 10 that is stacked on the leaf valve 10 is regulated. In the valve structure of the pneumatic shock absorber provided with the valve stopper 15, an annular wall member 17 that extends from the valve stopper 15 and faces the valve body 4 through a predetermined gap and covers the outer peripheral side of the leaf valve 10. The pressure change of the working gas is moderated to suppress the generation of the blowing sound of the working gas and improve the quietness of the pneumatic shock absorber.
[Selection] Figure 1

Description

  The present invention relates to an improvement in the valve structure of a pneumatic shock absorber.

As this type of valve structure, for example, a valve having a leaf valve laminated on a piston in which a port is formed and a valve stopper laminated on the leaf valve for regulating the deflection amount of the leaf valve has been known for a long time. (For example, refer to Patent Document 1).
JP 2004-324817 A (FIGS. 5 and 6)

  When the valve structure as described above is applied to a pneumatic shock absorber, there are the following problems.

  In the valve structure described above, the working fluid flows through a narrow gap between the leaf valve and the valve seat provided on the piston and flows into the large working chamber, so that the pressure rapidly decreases.

  When this valve structure is applied to an air pressure buffer whose working fluid is working gas, the sudden change in pressure causes the working gas to be ejected into a wide working chamber, and the working gas is emitted.

  When this valve structure is applied to a shock absorber whose working fluid is oil, the above-mentioned noise is not so much generated. However, when the working fluid is a working gas, the above-mentioned ejection sound is overlooked compared to oil. It becomes so large that it cannot be done, and it becomes a problem in terms of the quietness of the shock absorber.

  Therefore, the present invention was devised in order to improve the above-described problems, and the object of the present invention is to improve the quietness of the pneumatic shock absorber by suppressing the generation of a working gas jet noise and the like. It is to plan.

  The problem-solving means in the present invention includes an annular leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and regulates the deflection of the outer peripheral end of the leaf valve. In the valve structure of the pneumatic shock absorber, an annular wall member extending from the valve stopper and facing the valve body via a predetermined gap and covering the outer peripheral side of the leaf valve is provided.

  Another problem-solving means in the present invention includes a leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and regulates the deflection of the outer peripheral end of the leaf valve. In the valve structure of the pneumatic shock absorber provided with an annular wall member that extends from the valve body and faces the valve stopper via a predetermined gap and covers the outer peripheral side of the leaf valve.

  Further, another problem-solving means in the present invention includes a leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and regulates the bending of the outer peripheral end of the leaf valve. In the valve structure of the pneumatic shock absorber provided with an annular wall member provided with a through hole that covers the outer peripheral side of the leaf valve and allows the working gas to pass between the valve stopper and the valve body.

  Another problem-solving means in the present invention includes an annular leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and an inner peripheral end of the leaf valve that is stacked on the leaf valve. In the valve structure of the pneumatic shock absorber provided with a valve stopper to be regulated, an annular wall member is provided that extends from the valve stopper and faces the valve body via a predetermined gap and covers the inner peripheral side of the leaf valve. .

  In addition, another problem-solving means of the present invention includes a leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and regulates bending of the inner peripheral end of the leaf valve. An annular wall member extending from the valve body and facing the valve stopper via a predetermined gap and covering the inner peripheral side of the leaf valve is provided.

  In addition, another problem-solving means of the present invention includes a leaf valve that is stacked on a valve body in which a port is formed and that opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and regulates bending of the inner peripheral end of the leaf valve. In the valve structure of the pneumatic shock absorber provided with an annular wall member provided with a through hole that covers the inner peripheral side of the leaf valve and allows the working gas to pass between the valve stopper and the valve body. .

  According to the valve structure of the present invention, the working gas is decompressed once through the chamber defined by the wall member, the piston, and the valve stopper, and then ejected, so that the working gas flows into the rod side chamber R1 or the piston side chamber R2. Therefore, the pressure change of the working gas can be moderated, and the generation of the blowing sound of the working gas can be suppressed, thereby improving the quietness of the pneumatic buffer. it can.

  That is, with this valve structure, it is possible to improve the quietness of the pneumatic shock absorber, and particularly when applied to a pneumatic shock absorber for a vehicle, the vehicle occupant feels uncomfortable or uneasy. Can be avoided, thereby improving the riding comfort of the vehicle.

  Further, since the suppression of the generation of the working gas blowout sound and the like is achieved by a slight modification to the conventional valve structure in which a wall member is provided, the structure does not increase significantly and the structure becomes complicated. Therefore, the manufacturing process of the pneumatic shock absorber is not greatly changed.

  The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a longitudinal sectional view of a valve structure according to an embodiment. FIG. 2 is a schematic longitudinal sectional view of a pneumatic shock absorber in which a valve structure according to an embodiment is embodied. FIG. 3 is a longitudinal sectional view of a valve structure according to a modification of the embodiment. FIG. 4 is a longitudinal sectional view of a valve structure according to another embodiment. FIG. 5 is a longitudinal sectional view of a valve structure according to still another embodiment.

  As shown in FIGS. 1 and 2, the valve structure of the present invention is embodied in a piston portion of a pneumatic shock absorber K, and is laminated on a piston 4 as a valve body in which a plurality of ports 1 and 2 are formed. An annular leaf valve 10 that opens and closes the outlet end of the port 1, a valve stopper 15 that is stacked on the leaf valve 10 and restricts bending of the outer peripheral end of the leaf valve 10, and extends from the valve stopper 15 to provide a predetermined gap in the piston 4. And an annular wall member 17 that covers the outer peripheral side of the leaf valve 10.

  On the other hand, as will be described in detail later, the pneumatic shock absorber K in which this valve structure is embodied, as shown in FIG. 2, includes a cylinder 30, a head member 35 that seals the upper end of the cylinder 30, and a head member 35. A rod 33 slidably penetrating the rod, a piston 4 provided at an end of the rod 33, a rod side chamber R1 and a piston side chamber R2 partitioned by the piston 4 in the cylinder 30, and a bottom sealing the lower end of the cylinder 30 And a member 36.

  The piston 4 as the valve body will be described in detail below. As shown in FIG. 1, the piston 4 is inserted into the outer periphery of the disk portion 5 and the inner periphery of the cylinder 30 in sliding contact with the disk portion 5 formed in an annular plate shape. The disk portion 5 includes a piston ring 6, and the disk portion 5 communicates the rod-side chamber R1 and the piston-side chamber R2 and is a port 1 serving as a plurality of extension-side ports provided on the same circumference, and an extension-side port 1 A plurality of compression-side ports 2 formed alternately on the same circumference, a window 1a formed at the lower end in the figure of the disk portion 5 and communicated with the outlet end of the port 1, and an outlet end of the port 2 formed at the upper end in the figure And a valve seat 3a formed on the outer peripheral side of the window 1a on which the leaf valve 10 is seated, and a valve seat 3b formed on the outer peripheral side of the window 2a on which the leaf valve 10 is seated.

  In addition, the valve seats 3a and 3b are provided so as to surround the windows 1a and 2a, respectively, as shown in FIG. In a valve body in which the pressure side port 2 is arranged on the outer peripheral side of the port 1, an annular window that communicates with the ports 1 and 2 is formed, and the valve seat is also formed on the outer peripheral side of the annular window. Good.

  In addition, as shown in the figure, the leaf valve 10 is annular and plate-shaped, that is, formed as an annular plate-shaped valve body. In order to open and close the extension side port 1 and the pressure side port 2, the extension side leaf valve 10 is stacked on the lower end of the piston 4 in FIG. 1, and the pressure side leaf valve 10 is the upper end of the piston 4 in FIG. In addition, each leaf valve 10 has an inner peripheral side fixed to the reduced diameter portion 33a of the rod 33, and an outer peripheral side serving as a free end is brought into contact with the valve seats 3a and 3b.

  1 is provided with an annular member 11 having a diameter smaller than that of the leaf valve 10 in order to urge the leaf valve 10 toward the port 1. 33a is fixed and laminated.

  Further, a spacer 12 is laminated below the small-diameter annular member 11, and a valve stopper 15 for regulating the amount of deflection at the outer peripheral end of the extension-side leaf valve 10 is laminated below the spacer 12. The spacer 12 and the valve stopper 15 are also fixed to the diameter-reduced portion 33 a of the rod 33 on the inner peripheral side in the same manner as the annular member 11.

  The valve stopper 15 includes an annular main body 16 and a wall member 17 that extends from the outer peripheral end of the annular main body 16 and protrudes toward the piston 4 side.

  The wall member 17 is opposed to the piston 4 through a predetermined gap, and the inner peripheral diameter thereof is set larger than the outer peripheral diameter of the leaf valve 10 and covers the outer peripheral side of the leaf valve 10.

  That is, the chamber A is separated on the back pressure side of the leaf valve 10 by the valve stopper 15 including the piston 4 and the wall member 17. Note that the vertical length of the predetermined gap is such that the pressure in the room A when the pneumatic buffer K extends and the working gas passes through the port 1 and the leaf valve 10 is lower than the pressure in the port 1 and The pressure is set to be higher than the pressure in the piston side chamber R2.

  Further, an annular member 11 having a smaller diameter than that of the leaf valve 10 is fixed to the rod 33 on the inner peripheral side in order to urge the leaf valve 10 toward the port 2 in the upper pressure side leaf valve 10 in FIG. Further, a spacer 12 and a valve stopper 15 similar to the above are stacked above the annular member 11 with the inner peripheral side being fixed to the reduced diameter portion 33 a of the rod 33.

  Note that the piston B and the upper valve stopper 15 in FIG. 1 divide the room B on the back pressure side of the pressure side leaf valve 10. A predetermined gap is also formed between the wall member 17 of the leaf valve 15 and the piston 4, and the vertical length of the predetermined gap is determined by the compression operation of the pneumatic shock absorber K and the working gas is ported. 2 and the leaf valve 10 are set such that the pressure in the room B is lower than the pressure in the port 2 and higher than the pressure in the rod side chamber R1.

  That is, the reduced diameter portion 33a of the rod 33 includes a valve stopper 15, a spacer 12, an annular member 11, a leaf valve 10, a piston 4, a leaf valve 10, an annular member 11, a spacer 12 and a valve in order from the top in FIG. Each member is fixed to the reduced diameter portion 33a by a piston nut 34 to which a stopper 15 is attached and which is screwed to a screw portion 33b provided at the tip which is the lower end of the rod 33 in the drawing.

  In turn, as shown in FIG. 2, the pneumatic shock absorber K in which the above-described valve structure is embodied includes a cylinder 30, a piston 4 that partitions the inside of the cylinder 30 into a rod side chamber R <b> 1 and a piston side chamber R <b> 2, A rod 33 movably inserted into the cylinder 30 via 4, and an oil storage chamber T facing the sliding contact portion where the rod 33 and the annular seal S slidingly contacting the outer periphery of the rod 33 are so-called upright. Shaped as a shock absorber.

  Hereinafter, the cylinder 30 is formed in a cylindrical shape. The upper and lower ends of the cylinder 30 are closed by the head member 35 and the bottom member 36, respectively, and the piston 4 is slidably inserted into the cylinder 30. The inside of the cylinder 30 is partitioned into a rod side chamber R1 and a piston side chamber R2.

  The head member 35 is formed in an annular shape, and includes a bearing 41 that pivotally supports the rod 33 on the inner peripheral side, and a recess 42 that opens from the upper end side.

  The cylinder 30 described above is covered with a bottomed cylindrical outer cylinder 40 disposed outside the cylinder 30, and a reservoir R is formed in a gap between the outer cylinder 40 and the cylinder 30. Yes. Further, a bottom member 36 is fitted to the bottom of the outer cylinder 40, and a sealing member that holds an annular seal S on the inner peripheral side at the opening end that is the upper end of the outer cylinder 40 in FIG. 51 is fixed in a state of being laminated on the head member 35.

  In the sealing member 51 described above, in FIG. 1, the axial length as the vertical length is set shorter than the axial length as the vertical length of the annular seal S, and the annular seal S is sealed. It is held by the sealing member 51 so as to protrude from the lower end of the stop member 51 toward the inside of the cylinder 30. In the above description, the sealing member 51 holds the annular seal S. However, the annular seal S may be welded to the sealing member 51 so as not to be separated.

  The lower end of the annular seal S protruding from the sealing member 51 is disposed in the recess 42 of the head member 35, and the oil storage chamber T is separated by the recess 52 and the sealing member 51.

  A rod 33 that protrudes from the cylinder 30 and is slidably inserted into the bearing 41 of the head member 35 is inserted on the inner peripheral side of the annular seal S. The annular seal S is inserted into the rod 33 with a predetermined pressing force. It is press-contacted to the outer periphery.

  Therefore, the rod 33 penetrates the oil storage chamber T, and this oil storage chamber T faces the sliding contact portion between the rod 33 and the annular seal S.

  Further, the oil storage chamber T communicates with the rod-side chamber R1 through a passage 43 provided in the head member 35 and communicates with the inside of the reservoir R through a passage 44.

  Here, the end 43a of the passage 43 on the oil storage chamber T side opens from the side wall 42a of the recess 42, and the end 43a is positioned at least above the lowermost end of the annular seal S in the figure. Is set to Further, a check valve 45 serving as a check valve that allows only the flow of fluid from the oil storage chamber T toward the rod side chamber R1 is provided in the middle of the passage 43.

  On the other hand, the bottom member 36 is provided with a passage 46 forming a part of a passage communicating the piston-side chamber R2 and the reservoir R. In the middle of the passage 46, only the flow of fluid from the piston-side chamber R2 toward the reservoir R is provided. A check valve 47 is provided.

  The cylinder 30 is filled with working gas, and the oil storage chamber T and the reservoir R are filled with oil. The oil level O of the oil in the oil storage chamber T is within the oil storage chamber T. The reservoir R is filled with a sufficient amount of oil in consideration of the fact that the working gas pressure and the working gas pressure in the reservoir R do not drop below the lowermost end of the annular seal S due to the balance.

  The rod side chamber R1 and the piston side chamber R2 are also filled with a small amount of oil. However, the oil filled in the rod side chamber R1 is used when the pneumatic shock absorber performs expansion and contraction for the first time. The oil in the piston side chamber R2 is supplied before the working gas into the reservoir R when the pneumatic shock absorber is contracted to prevent the oil level O in the oil storage chamber T from descending. It is to do.

  Next, the operation of the valve structure configured as described above will be described. First, when the pneumatic shock absorber K is extended, the rod side chamber R1 is compressed and the piston side chamber R2 is expanded, so that the working gas in the rod side chamber R1 moves into the piston side chamber R2 via the port 1. . During this movement, the working gas deflects the outer peripheral end of the extension-side leaf valve 10 positioned downward in FIG. 1 to separate from the valve seat 3a, flows into the chamber A, passes through the gap, and from the rod-side chamber R1. It will flow into the piston side chamber R2.

  Then, when the working gas deflects the leaf valve 10 and passes through the port 1 and the chamber A, a pressure loss occurs, and there is a difference between the pressure in the rod side chamber R1 and the pressure in the piston side chamber R2, which is commensurate with this pressure difference. Damping force is generated.

  Here, the working gas does not flow directly from the port 1 into the piston side chamber R2, but flows into the piston side chamber R2 once through the chamber A defined by the valve stopper 15 including the piston 4 and the wall member 17. Therefore, when it flows into the room A, it is once decompressed and then flows into the piston side chamber R2.

  Then, compared to the sudden pressure change when the working gas flows directly from the port 1 into the piston side chamber R2, the pressure change when the working gas flows into the chamber A from the port 1 and the piston A chamber R2 from the chamber A. Since both the pressure changes when flowing into the valve are moderate, in this valve structure, it is possible to suppress the generation of a blowing sound or the like when the working gas is blown into the piston side chamber R2. The quietness of the pneumatic shock absorber K can be improved.

  Since the oil in the rod side chamber R1 is heavier than the working gas and is accumulated in the opening of the port 1, the oil also moves into the piston side chamber R2 together with the working gas.

  The oil in the rod side chamber R1 has a role of lubricating between the cylinder 30 and the piston 4 as described above. However, since the oil passes through the port 1 before the working gas, the oil in the rod side chamber R1. This will promptly increase the pressure.

  Subsequently, when the pneumatic shock absorber K contracts, the piston side chamber R2 is compressed and the rod side chamber R1 is expanded, so that the working gas in the piston side chamber R2 moves into the rod side chamber R1 via the port 2. To do. During this movement, the working gas deflects the outer peripheral end of the pressure-side leaf valve 10 located in the upper part in FIG. 1, separates it from the valve seat 3b, flows into the chamber B, passes through the gap, and rods from the piston-side chamber R2. It will flow into the side chamber R1.

  When the working gas deflects the leaf valve 10 and passes through the port 2 and the chamber B, a pressure loss occurs, and a difference can be made between the pressure in the rod side chamber R1 and the pressure in the piston side chamber R2, and this pressure difference is met. Damping force is generated.

  Here, the working gas does not directly flow into the rod side chamber R1 from the port 2, but flows into the rod side chamber R1 once through the chamber B defined by the valve stopper 15 including the piston 4 and the wall member 17. Therefore, when it flows into the room B, it is once depressurized and then flows into the rod side chamber R1.

  Then, compared to the sudden pressure change when the working gas flows directly from the port 2 into the rod side chamber R1, the pressure change when the working gas flows into the room B from the port 2 and the rod side chamber R1 from the room B. Since the pressure changes when flowing into the cylinder are both gentle, in this valve structure, it is possible to suppress the generation of an ejection sound or the like when the working gas is ejected into the rod side chamber R1. The quietness of the pneumatic shock absorber K can be improved.

  That is, in this valve structure, it is possible to improve the quietness of the pneumatic shock absorber K. In particular, when applied to a pneumatic shock absorber for a vehicle, the vehicle occupant feels uncomfortable or uneasy. A trouble that gives a feeling is avoided, and this makes it possible to improve the riding comfort of the vehicle.

  Furthermore, as described above, since the suppression of the generation of the working gas ejection noise and the like is achieved by a slight modification to the conventional valve structure in which the wall member 17 is provided in the valve stopper 15, a significant cost is required. No increase is caused, the structure is not complicated, and the manufacturing process of the pneumatic shock absorber is not greatly changed.

  The working gas in the piston side chamber R2 also flows into the reservoir R via the passage 46 due to the pressure increase in the piston side chamber R2.

  At this time, since the oil in the piston side chamber R2 is heavier than the working gas and is accumulated in the opening of the passage 46, the oil also moves into the reservoir R together with the working gas.

  Since the oil in the piston side chamber R2 passes through the passage 46 prior to the working gas, it prompts a rapid pressure increase in the piston side chamber R2.

  The reservoir R and the oil storage chamber T are pressurized in the same manner as the piston-side chamber R2, so that the oil in the reservoir R flows into the oil storage chamber T, and further the oil in the oil storage chamber T The oil level O will rise.

  Then, the oil in the oil storage chamber T flows through the passage 43 and the working gas into the rod side chamber R1 due to the rise in the oil level O and the pressure increase in the oil storage chamber T. Here, since the opening position of the end 43a of the passage 43 is located above the lowermost end of the annular seal S, the oil storage chamber T even if the oil moves from the oil storage chamber T into the rod side chamber R1 as described above. The oil level O of the inner oil is always located above the lowermost end of the annular seal S, and the oil in the oil storage chamber T continues to maintain the lubrication of the sliding contact portion between the rod 33 and the annular seal S. .

  Therefore, even if this pneumatic shock absorber K repeatedly expands and contracts, the oil in the oil storage chamber T continues to maintain the lubrication of the sliding contact portion between the rod 33 and the annular seal S and is formed upright. In addition, the sliding portion of the rod 33 of the pneumatic shock absorber K is reliably lubricated.

  In addition, by providing an oil storage chamber T facing the sliding contact portion of the rod 33 and positioning the oil surface above the lowermost end of the sliding contact portion, the sliding portion can be reliably lubricated. The pneumatic shock absorber can be made upright without being complicated and without significant cost increase.

  And since the sliding contact part of the rod 33 and the annular seal S is reliably lubricated as described above, the smooth telescopic operation of the pneumatic shock absorber K is guaranteed, and the practicality of the pneumatic shock absorber is improved. Since the wear resistance of the annular seal S is improved, the sealing performance of the pneumatic shock absorber is also improved.

  When the pneumatic shock absorber K continues to expand and contract, the oil in the pneumatic shock absorber K circulates through the rod side chamber R1, the piston side chamber R2, the reservoir R, and the oil storage chamber T, and the sliding portion of the pneumatic shock absorber K That is, the sliding portion between the cylinder 30 and the piston 4 and the sliding portion of the rod 33 and the annular seal S are continuously lubricated.

  That is, in the pneumatic shock absorber K, the oil circulation can prevent the oil from being lost in the rod side chamber R1, and the sliding portion between the cylinder 30 and the piston 4 can be lubricated. In combination with the lubrication of the sliding contact portion between the rod 33 and the annular seal S, the pneumatic shock absorber K can be smoothly expanded and contracted, the manual resistance can be reduced, and the riding comfort in the vehicle can be improved. At the same time, the durability of the pneumatic shock absorber K can be improved.

  Next, a valve structure in a modification of the embodiment will be described. As shown in FIG. 3, the valve structure according to the modification of the embodiment is embodied in the piston portion of the pneumatic shock absorber K described above. However, in the valve structure according to the embodiment, the valve structure The wall member 17 provided in the stopper 15 is different from the valve structure in the embodiment in that the wall member 17 is provided in a piston 61 which is a valve body.

  Hereinafter, different parts will be described in detail, and the same parts as those of the valve structure in the above-described embodiment will be given the same reference numerals, and detailed description thereof will be omitted.

  As shown in FIG. 3, the piston 61 includes wall members 63 and 64 projecting toward the annular plate-like valve stopper 70 on the outer peripheral side of the upper and lower ends in FIG. 3 of the disc portion 62 formed in the annular plate shape. In other respects, the piston 4 is provided with ports 1 and 2, a piston ring 6, windows 1a and 2a, and valve seats 3a and 3b in the same manner as the piston 4 in the embodiment.

  3, the leaf valve 10, the annular member 11, and the spacer 12 are respectively laminated on the upper and lower ends of the piston 61 in FIG. 3, and the valve stopper 70 is further laminated. Each member is attached to the reduced diameter portion 33 a of the rod 33.

  The wall member 63 described above faces the valve stopper 70 through a predetermined gap, and the inner peripheral diameter thereof is set larger than the outer peripheral diameter of the leaf valve 10 and covers the outer peripheral side of the leaf valve 10. The chamber A <b> 1 is separated on the back pressure side of the leaf valve 10 by the piston 61 provided with the wall member 63 and the valve stopper 70.

  Similarly, the other wall member 64 is opposed to the valve stopper 70 via a predetermined gap, and its inner peripheral diameter is set larger than the outer peripheral diameter of the leaf valve 10 and covers the outer peripheral side of the leaf valve 10. The chamber B <b> 1 is separated from the back pressure side of the leaf valve 10 by the piston 61 having the wall member 64 and the valve stopper 70.

  As for the length of the predetermined gap in the vertical direction, the pressure in the chambers A1 and B1 is lower than the pressure in the ports 1 and 2, respectively, during the expansion and contraction operation of the pneumatic shock absorber K, as in the above-described embodiment. And it is set so that it may become higher than the pressure in rod side chamber R1 and piston side chamber R2.

  Therefore, even in the valve structure in the modification of this embodiment, the working gas does not flow directly from the ports 1 and 2 into the rod side chamber R1 or the piston side chamber R2, but includes the wall members 63 and 64. Since the pressure is once reduced through the chambers A1 and B1 defined by the piston 61 and the valve stopper 70 and then flows into the rod side chamber R1 or the piston side chamber R2, the working gas is jetted into the rod side chamber R1 or the piston side chamber R2. It is possible to suppress the generation of a blowing sound or the like during the operation, thereby improving the quietness of the pneumatic shock absorber K.

  That is, even in the valve structure in the modified example of this embodiment, it is possible to improve the quietness of the pneumatic shock absorber K, particularly when applied to a pneumatic shock absorber for a vehicle. Thus, the problem of making the vehicle occupant feel uncomfortable or uneasy can be avoided, thereby improving the riding comfort of the vehicle.

  And as mentioned above, since suppression of generation | occurrence | production of the blowing-out sound of the said working gas, etc. is achieved by the slight modification with respect to the conventional valve structure of providing the wall members 63 and 64 in the piston 61, it is large. The cost is not increased, the structure is not complicated, and the manufacturing process of the pneumatic shock absorber is not greatly changed.

  Furthermore, the valve structure in another embodiment shown in FIG. 4 will be described. In the valve structure in the other embodiment, the leaf valve 10, the annular member 11, the spacer 12 and the modified example of the embodiment are respectively provided at the upper and lower ends in FIG. 4 of the piston 4 in the embodiment. The valve stopper 70 is laminated, and annular wall members 71 and 71 are interposed between the piston 4 and the valve stopper 70, which is also embodied in the piston portion of the pneumatic shock absorber K. It has become.

  The wall members 71 are formed in an annular shape as described above, and the inner peripheral diameter thereof is set to be larger than the outer peripheral diameter of the leaf valve 10, and as described above, between the piston 4 and the valve stopper 70. And the wall members 71, 71, the piston 4 and the valve stoppers 70, 70 separate the chambers A2, B2, respectively.

  The wall members 71 and 71 are provided with a plurality of slits 72 each serving as a through hole. The chamber A2 communicates with the piston side chamber R2 and the chamber B2 communicates with the rod side chamber R1 through the slits 72. Has been.

  As for the opening area of the slit 72, the pressure in the chambers A2 and B2 is lower than the pressure in the ports 1 and 2, respectively, during the expansion and contraction operation of the pneumatic shock absorber K, as in the above-described one embodiment. The pressure is set to be higher than the pressure in the rod side chamber R1 and the piston side chamber R2.

  Therefore, even in the valve structure in this other embodiment, the working gas does not flow directly from the ports 1 and 2 into the rod side chamber R1 or the piston side chamber R2, but the wall members 71 and 71, the piston 4 and the valve. Since the pressure is once reduced through the chambers A2 and B2 defined by the stopper 70 and then flows into the rod side chamber R1 or the piston side chamber R2, the ejection when the working gas is ejected into the rod side chamber R1 or the piston side chamber R2. Generation | occurrence | production of a squeal etc. can be suppressed and the improvement of the silence of the pneumatic buffer K can be aimed at by this.

  That is, even in the valve structure in the other embodiments, it is possible to improve the quietness of the pneumatic shock absorber K. In particular, when applied to a pneumatic shock absorber for a vehicle, the vehicle Problems that make the passenger feel uncomfortable or uneasy can be avoided, thereby improving the riding comfort of the vehicle.

  Further, as described above, a slight modification to the conventional valve structure in which the suppression of the generation of the working gas ejection sound and the like is such that the wall members 71 and 71 are interposed between the piston 4 and the valve stopper 70. As a result, the structure is not complicated and the manufacturing process of the pneumatic shock absorber is not greatly changed.

  In the above description, the wall member 71 is provided with slits 72 to form through holes. However, the wall member 71 may be made of a porous metal having continuous pores or a resin having continuous pores. By setting it as a porous metal with continuous pores or a resin with continuous pores, the wall member itself originally has through-holes, so it is possible to save time and effort to newly provide through-holes such as slits, In this case, there is an advantage that a part of the manufacturing process of the valve structure can be omitted.

  Furthermore, although the wall member 71 is a separate member from the valve stopper 70 and the piston 4 as described above, the wall member 71 may be integrated with the valve stopper 70 or the piston 4.

  In the valve structure in the above-described embodiment, the leaf valve 10 is configured as a so-called outwardly-open valve in which the inner peripheral side is fixed and the outer peripheral side is a free end. You may comprise as a so-called inward opening valve | bulb which makes a peripheral end a free end.

  In this case, as in the valve structure in still another embodiment shown in FIG. 5, the valve body 90 includes a disk-shaped main body 91 and an annular socket that is erected on the outer peripheral side of the disk-shaped main body 91. The leaf valve 80 is, of course, a valve stopper 83 having an annular member 81, a spacer 82 and a wall member 84 inserted into the socket 92 and laminated on the disk-shaped main body 91. The outer peripheral side is fixed and the inner peripheral side is the free end, and the leaf valve 80 may be seated on the valve seat 94 formed at the outlet end of the port 93 provided in the disc-shaped main body 91.

  In the valve structure configured as described above, the wall member 84 extends from the inner peripheral end of the valve stopper 83, and the outer diameter thereof is set smaller than the inner peripheral diameter of the leaf valve 80. The room A <b> 3 can be separated from the back side of the leaf valve 80 so as to cover the inner peripheral side of the leaf valve 80.

  Therefore, even in the valve structure in this further embodiment, the operating gas passes through the port 93 and passes through the room A4 only by opening the leaf valve 80 inward. For the above, there is no change with the valve structure in the above-described one embodiment, as described above, the pressure change of the working gas can be moderated, and the generation of the blowing sound of the working gas can be suppressed, This can improve the quietness of the pneumatic shock absorber.

  That is, with this valve structure, it is possible to improve the quietness of the pneumatic shock absorber, and particularly when applied to a pneumatic shock absorber for a vehicle, the vehicle occupant feels uncomfortable or uneasy. Can be avoided, thereby improving the riding comfort of the vehicle.

  Furthermore, as described above, since the suppression of the generation of the working gas ejection sound and the like is achieved by a slight modification to the conventional valve structure in which the wall member 84 is provided in the valve stopper 83, a significant cost is required. No increase is caused, the structure is not complicated, and the manufacturing process of the pneumatic shock absorber is not greatly changed.

  Although not shown, as is apparent from the above description, when the wall member is provided on the valve body side as in the valve structure of the modification of the embodiment, as in the valve structure in the other embodiments. Even when a wall member is interposed between the valve stopper and the valve body, it is possible to configure these valve structures as so-called inwardly opening valves in which the inner peripheral side of the leaf valve is a free end.

  Further, from the above description, the case where the valve structure of the present invention is embodied in the piston portion of the shock absorber has been described, but it is needless to say that the valve structure may be embodied in the base valve portion. Speaking of K, it is configured as a so-called single rod type shock absorber, but may be configured as a double rod type shock absorber, and in the pneumatic shock absorber of the present embodiment, it is particularly a sliding part. However, the structure of the pneumatic shock absorber is not limited to this, but a structure in which a small amount of oil is circulated through the rod side chamber R1, the piston side chamber R2, and the oil storage chamber T is taken into consideration.

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

It is a longitudinal cross-sectional view of the valve structure in one embodiment. It is a schematic longitudinal cross-sectional view of the pneumatic shock absorber with which the valve structure in one embodiment was embodied. It is a longitudinal cross-sectional view of the valve structure in the modified example of one embodiment. It is a longitudinal cross-sectional view of the valve structure in other embodiment. It is a longitudinal cross-sectional view of the valve | bulb structure in other embodiment.

Explanation of symbols

1, 2, 93 Ports 1a, 2a Windows 3a, 3b, 94 Valve seats 4, 61 Pistons 5, 62 as valve bodies 6 Disc portions 6 Piston rings 10, 80 Leaf valves 11, 81 Annular members 12, 82 Spacers 15, 70 , 83 Valve stopper 16 Annular body 17, 63, 64, 71, 84 Wall member 30 Cylinder 33 Rod 33a Reduced diameter portion 33b Screw portion 34 Piston nut 35 Head member 36 Bottom member 40 Outer cylinder 41 Bearing 42 Recess 42a Side wall portion 43 44, 46 Passage 43a End 45, 47 Check valve 51 Sealing member 72 Through hole slit 90 Valve body 91 Disc-shaped main body 92 Socket A, A2, A3, B1, B2 Room K Pneumatic shock absorber O Oil level R1 Rod side chamber R2 Piston side chamber S Annular seal T Oil storage chamber

Claims (7)

Pneumatic shock absorber valve structure including an annular leaf valve that is stacked on the valve body in which the port is formed and opens and closes the outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts the deflection of the outer peripheral end of the leaf valve A valve structure for a pneumatic shock absorber, wherein an annular wall member extending from the valve stopper and facing the valve body via a predetermined gap and covering the outer peripheral side of the leaf valve is provided. In the valve structure of the pneumatic shock absorber provided with a leaf valve that is stacked on the valve body in which the port is formed and opens and closes the outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts the deflection of the outer peripheral end of the leaf valve. A valve structure of a pneumatic shock absorber, characterized in that an annular wall member extending from the valve body and facing the valve stopper via a predetermined gap and covering the outer peripheral side of the leaf valve is provided. In the valve structure of the pneumatic shock absorber provided with a leaf valve that is stacked on the valve body in which the port is formed and opens and closes the outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts the deflection of the outer peripheral end of the leaf valve. A valve structure for a pneumatic shock absorber, characterized in that an annular wall member provided with a through hole that covers the outer peripheral side of the leaf valve and allows the passage of working gas is provided between the valve stopper and the valve body. Pneumatic shock absorber valve having an annular leaf valve that is stacked on the valve body in which the port is formed and opens and closes the outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts the deflection of the inner peripheral end of the leaf valve A pneumatic shock absorber valve structure characterized in that an annular wall member extending from the valve stopper and facing the valve body via a predetermined gap and covering the inner peripheral side of the leaf valve is provided. In a valve structure of a pneumatic shock absorber, comprising a leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts bending of the inner peripheral end of the leaf valve A valve structure for a pneumatic shock absorber, characterized in that an annular wall member extending from the valve body and facing the valve stopper via a predetermined gap and covering the inner peripheral side of the leaf valve is provided. In a valve structure of a pneumatic shock absorber, comprising a leaf valve that is stacked on a valve body in which a port is formed and opens and closes an outlet end of the port, and a valve stopper that is stacked on the leaf valve and restricts bending of the inner peripheral end of the leaf valve A valve structure for a pneumatic shock absorber, characterized in that an annular wall member is provided between the valve stopper and the valve body so as to cover the inner peripheral side of the leaf valve and to allow a working gas to pass therethrough. . 7. The valve structure of the pneumatic shock absorber according to claim 3, wherein the wall member is formed of a porous metal having continuous pores or a resin having continuous pores.

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