JP2010261547A - Valve structure - Google Patents

Abstract

It is an object of the present invention to provide a valve structure that can improve the ride comfort in a vehicle and can easily tune a damping characteristic without providing a device such as a control device or a motor for driving the valve.
SOLUTION: A first valve disk 9 having a soft side flow path S communicating between one chamber 41 and the other chamber 42 separated in the shock absorber, and the soft side flow path S are arranged in parallel in the shock absorber. A second valve disk 3 having a hard side flow path H communicating with one chamber 41 and the other chamber 42, a soft side valve 4 for opening and closing the soft side flow path S, and a hard side flow path H. And the open / close valve 6 that closes the soft flow path S when the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount.
[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 the outlet end of a flow path provided in the piston portion. What opens and closes a flow path is known.

  In such a valve structure, from the viewpoint of ride comfort in the vehicle, it is better to set the damping force when the shock absorber expands and contracts at low and medium speeds. There is a problem that it is likely to be in the most compressed state or the most expanded state. In addition, when the shock absorber is in the most compressed state or the most extended state, the piston collides with a member such as a cap or a rod guide that closes the cylinder end, so that sound and impact are generated and the ride comfort in the vehicle is increased. It will be lost.

  Therefore, the damping characteristics of the shock absorber (characteristics of the damping force with respect to the piston speed) are relatively low when the piston speed is in the low and medium speed ranges, and high when the piston speed is in the high speed range. It may be desirable to have characteristics.

  As a valve structure for realizing this, for example, a bypass path that bypasses the flow path provided in the piston portion is provided in the piston rod, and a rotary valve that is rotatably inserted into the bypass path of the piston rod is driven by a motor. (For example, refer to Patent Document 1).

  In addition, a separate throttle valve is provided on the upstream side of the flow path that is provided on the piston and is opened and closed by a leaf valve, and when the piston speed reaches a high speed range, a valve structure that throttles the passage on the upstream side of the flow path with the throttle valve ( For example, there is also a proposal of Patent Document 2).

JP 2008-39065 A (FIG. 1) JP 2008-208870 A

However, in the valve structure disclosed in JP 2008-39065 A described above, the damping force of the shock absorber is adjusted by adjusting the opening of the rotary valve with a motor. Various devices such as a sensor for detecting the piston speed and a control device for controlling the motor must be installed in the shock absorber, which increases the cost of the shock absorber. On the other hand, the above-mentioned JP 2008-208870 A In the valve structure disclosed in No. 1, the leaf valve and the throttle valve are connected in series, but the damping characteristic is the same as that of the leaf valve. When one of the characteristics is changed, the characteristics of the entire shock absorber also change, which makes it difficult to tune.

  Accordingly, the present invention has been developed to improve the above-described problems, and the object of the present invention is to improve the riding comfort in a vehicle without providing a device such as a control device or a motor for driving a valve. It is possible to provide a valve structure that can be easily tuned for damping characteristics.

  In order to solve the above-described object, the problem-solving means in the present invention includes a first valve disk having a soft-side flow path that communicates one chamber and the other chamber separated in a shock absorber, and a soft-side flow. A second valve disk having a hard-side flow path that communicates between the one chamber and the other chamber that are arranged in parallel in the buffer, and a hard-side flow; a soft-side valve that opens and closes the soft-side flow path; A hard side valve that opens and closes the path and an open / close valve that closes the soft side flow path when the pressure in one chamber exceeds the pressure in the other chamber by a predetermined amount are provided.

  Further, another problem solving means in the present invention includes an annular first valve disk having a soft-side flow path communicating between one chamber and the other chamber separated in the shock absorber, and a soft-side flow path in parallel. An annular second valve disk having a hard-side flow path that communicates between the one chamber and the other chamber separated in the shock absorber, a soft-side valve that opens and closes the soft-side flow path, and a hard-side flow path A hard side valve that opens and closes the rod, a rod that connects the first valve disc and the second valve disc, and is mounted on the outer periphery of the rod and fitted to the outer periphery of the first valve disc. A cylindrical cap that forms a chamber, and an open / close valve that closes the soft-side channel when the pressure in the one chamber exceeds the pressure in the other chamber by a predetermined amount, and the soft-side channel has a hollow hole provided in the rod; , Provided in the room and the first valve disc Characterized in that it is formed by the soft side port.

  Furthermore, another problem-solving means in the present invention includes an annular first valve disk having a soft-side flow path communicating between the one chamber and the other chamber separated in the shock absorber, and a soft-side flow path in parallel. An annular second valve disk having a hard-side flow path that communicates between the one chamber and the other chamber separated in the shock absorber, a soft-side valve that opens and closes the soft-side flow path, and a hard-side flow path A hard side valve that opens and closes the rod, a rod that connects the first valve disc and the second valve disc, and is mounted on the outer periphery of the rod and fitted to the outer periphery of the first valve disc. With a cylindrical cap that forms a chamber, and a hard-side flow path is provided in the second valve disk so that the one-side hard-side port and the one-side hard-side port communicate with each other. Hard on the other side The hard side valve is stacked on the other chamber side of the second valve disc, and the one side hard side leaf valve that opens and closes the one side hard side port and the second valve disc is stacked on the one chamber side. The other side hard side leaf valve for opening and closing the other side hard side port, the soft side flow path provided in the rod, the chamber, the first valve disc provided in the one chamber and the chamber The soft side port on one side and the soft side port on the other side in parallel with the soft side port on the one side, and the soft side valve is stacked on the room side of the first valve disk to A soft side leaf valve on one side that opens and closes the soft side port and a soft side leaf valve on the other side that opens and closes the soft side port on the other side stacked on one chamber side of the first valve disc. In addition, an open / close valve is provided that closes the soft flow path when the pressure in one chamber exceeds a predetermined amount by the pressure in the other chamber and closes the soft flow path when the pressure in the other chamber exceeds a predetermined amount by the pressure in the other chamber. And

  According to the valve structure of the present invention, when the piston speed is in the medium speed region, the damping force is kept low, and when the piston speed reaches the high speed region, the damping force is higher than when the piston speed is in the medium speed region. Even when the piston speed reaches the high speed region, the damping force is not insufficient, vibration is sufficiently suppressed, and the riding comfort in the vehicle can be improved.

  In addition, in a situation where the amplitude at which the shock absorber expands or contracts most is large and the piston speed reaches the high speed region, the damping force generated by the shock absorber can be increased. The speed can be quickly reduced, and the impact at the time of maximum expansion or contraction can be reduced.

  Furthermore, the soft side valve and the hard side valve do not affect each other in the damping characteristics even if the setting is changed, so the tuning of the damping characteristics and the piston speed are in the high speed range when the piston speed is in the low and medium speed range. Tuning of the damping characteristics at the time becomes easy, and the degree of freedom in design is also greatly improved.

  In addition, this valve structure does not require various devices such as a sensor for detecting the piston speed, a motor for driving the valve, and a control device for controlling the motor. Absent.

It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in one embodiment was embodied. It is a figure which shows the damping characteristic in the buffer which embodied the valve | bulb structure of one Embodiment. It is a figure which shows the other example of the damping characteristic in the buffer which embodied the valve | bulb structure of one Embodiment. It is a longitudinal cross-sectional view of the piston part of the shock absorber by which the valve structure in one modification of one embodiment was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in the other modification of one embodiment was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in other embodiments was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in one modification of other embodiment was embodied. It is a longitudinal cross-sectional view of the piston part of the shock absorber in which the valve structure in other modifications of other embodiments was embodied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the valve structure in one embodiment is embodied in both the expansion side and compression side damping valves of the piston portion of the shock absorber, and includes a one chamber 41 separated in the shock absorber. An annular first valve disk 9 having a soft-side flow path S communicating with the other chamber 42, and one chamber 41 and the other chamber 42 that are arranged in parallel in the soft-side flow path S and separated in a shock absorber. An annular second valve disk 3 having a hard side flow path H communicating therewith, a soft side valve 4 for opening and closing the soft side flow path S, a hard side valve 5 for opening and closing the hard side flow path H, and a first valve A rod 2 that connects the disc 9 and the second valve disc 3 is mounted on the outer periphery of the rod 2 and is fitted to the outer periphery of the first valve disc 9 to form a chamber 11 between the first valve disc 9. The cylindrical cap 10 and the one chamber 41 An opening / closing valve 6 is provided that closes the soft flow path S when the force exceeds the pressure in the other chamber 42 by a predetermined amount and closes the soft flow path S when the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount. Has been.

  On the other hand, the shock absorber in which the valve structure of the present invention is embodied is well known and will not be described in detail, but specifically, for example, a cylinder 1 and a rod 2 movably inserted into the cylinder 1. And slidably inserted into the cylinder 1 and mounted on the outer periphery of the rod 2 to divide the inside of the cylinder 1 into an upper one chamber 41 and a lower other chamber 42, and the one chamber 41 and the other chamber 42. The second valve disk 3 provided with a hard side flow path H that communicates with the first side, and the soft side flow path S that bypasses the hard side flow path H and communicates the one chamber 41 and the other chamber 42 with each other. A hydraulic fluid such as hydraulic oil is sealed in the cylinder 1. In the shock absorber D, the damping characteristic is changed by opening and closing the soft-side flow path S by the on-off valve 6 described above.

  Further, when the working fluid is liquid, when the shock absorber expands / contracts, the rod 2 enters or leaves the cylinder 1 to compensate for the amount of liquid that becomes excessive or insufficient in the cylinder 1. Although not shown, it is natural that a gas chamber defined by a free piston inserted below the cylinder 1 or a reservoir communicating with the cylinder 1 is provided. The working fluid is not limited to working oil, and may be a liquid other gas such as water or an aqueous solution.

  Further, in this document, in order to facilitate the description of each part, a member that functions when the working fluid flows from the one chamber 41 to the other chamber 42 is a member on one side, and the working fluid from the other chamber 42 to the one chamber 41. About the member which functions when flowing, the member of the same name is distinguished as a member on the other side.

  In the valve structure, the piston 1 moves up and down in FIG. 1 with respect to the cylinder 1, and the one chamber 41 and the other chamber 42 are connected via the soft side flow path S and the hard side flow path H. When the working fluid goes back and forth, the soft side valve 4 and the hard side valve 5 respectively provide resistance to the flow of the working fluid to cause a predetermined pressure loss, thereby generating a predetermined damping force in the buffer. It functions as a damping force generating element.

  Hereinafter, the valve structure will be described in detail. The second valve disk 3 is slidably inserted into the cylinder 1 of the shock absorber, and serves as a piston that separates the inside of the cylinder 1 into one chamber 41 and the other chamber 42. It is functioning. Further, the second valve disk 3 is formed in an annular shape so that the working fluid passes through the one chamber 41 and the other chamber 42 when the shock absorber extends, and the one hard side port 3a and the other chamber 42 are passed. And the other side hard side port 3b through which the working fluid passes when the shock absorber compresses, and a hard side flow path H is formed by these hard side ports 3a and 3b. ing. Further, a hard leaf valve 5a on one side is stacked on the other chamber 42 side of the second valve disc 3, and the outlet end of the hard side port 3a on one side is opened and closed by the hard leaf valve 5a. Further, the other side hard side leaf valve 5b is laminated on the one chamber 41 side of the second valve disc 3, and the other side hard side port 3b is stacked by this hard side leaf valve 5b. The outlet end of the door is opened and closed. That is, in the case of this embodiment, the hard side valve 5 that opens and closes the hard side flow path H is constituted by these hard side leaf valves 5a and 5b. The hard side valve 5 may be a damping valve other than the leaf valve, but by configuring the hard side valve 5 with the hard side leaf valves 5a and 5b in this way, the piston portion of the valve portion embodying the valve structure is provided. An increase in the overall length can be avoided.

  Therefore, when the shock absorber is extended, the one-side hard-side leaf valve 5a passes through the one-side hard-side port 3a and the one chamber 41 on the upper side in FIG. 1 to the other chamber 42 on the lower side in FIG. A resistance is applied to the flow of the working fluid that moves to the shock absorber to generate a damping force on the expansion side, and the hard side leaf valve 5b on the other side is connected to the hard side port 3b on the other side when the shock absorber is compressed. A resistance is applied to the flow of the working fluid that passes from the other chamber 42 to the one chamber 41 through the other chamber 42 to generate a compression-side damping force.

  Further, a spacer 7 is laminated on the upper side of the above-mentioned hard side leaf valve 5b on the other side in FIG. 1, and this spacer 7 is annular and has an annular groove 7a at the upper end in FIG. And a groove 7b communicating with the annular groove 7a.

  Further, a bottomed cylindrical cap 10, a cylindrical member 8, one side soft side leaf valve 4a, a first valve disc 9, and the other side soft side leaf valve 4b are stacked above the spacer 7 in FIG. The cap 10 and the first valve disk 9 form a chamber 11. The spacer 7, the cap 10, the cylindrical member 8, the one side soft side leaf valve 4 a, the first valve disc 9 and the other side soft side leaf valve 4 b are separated by the second valve disc 9. The room 11 is formed in the one room 41.

  Specifically, the first valve disk 9 is formed in an annular shape, and passes through the top and bottom of the first valve disk 9 so as to communicate the one chamber 41 and the room 11. And the other soft side port 9b. The first valve disc 9 is set to have a smaller outer diameter than the second valve disc 9 and an annular gap is provided between the first valve disc 9 and the cylinder 1 so as not to hinder the passage of the working fluid.

  The outlet of the soft side port 9a on one side is opened and closed by the soft side leaf valve 4a on one side stacked below the first valve disc 9 in FIG. 1, and the shock absorber is extended in the soft side port 9a on the one side. It is set to a one-way passage that is opened only at a certain time, and resistance is given to the passing working fluid by the soft leaf valve 4a on one side. On the other hand, the outlet of the soft side port 9b on the other side is opened and closed by the soft side leaf valve 4b on the other side of the first valve disc 9 stacked in FIG. 1, and the shock absorber is compressed on the soft side port 9b on the other side. It is set as a one-way passage that is opened only during the stroke, and resistance is given to the passing working fluid by the soft side leaf valve 4b on the other side. That is, the soft side valve 4 includes the one side soft side leaf valve 4a and the other side soft side leaf valve 4b. The soft side valve 4 may be a damping valve other than the leaf valve. However, by configuring the soft side valve 4 with the soft side leaf valves 4a and 4b in this way, the valve structure of the piston portion is realized. An increase in the overall length can be avoided. The bending rigidity of the soft side leaf valves 4a and 4b is set in advance smaller than the bending rigidity of the hard side leaf valves 5a and 5b stacked on the second valve disk 3 functioning as a piston. The soft-side ports 9a and 9b are opened and greatly bent by the valve opening pressure lower than the valve opening pressure in the valves 5a and 5b.

  Further, the cap 10 is formed in a bottomed cylindrical shape, and is provided with a rod insertion hole 10a allowing the insertion of the rod 2 and a through hole 10b facing the annular groove 7a of the spacer 7 at the bottom, and the cylindrical portion. 1 is engaged with the outer periphery of the lower end in FIG. 1 of the first valve disc 9 described above, and separates the chamber 11 in cooperation with the first valve disc 9 as described above.

  And between the bottom part of this cap 10 and the 1st valve disc 9, the cylinder member 8 which is a top cylinder shape and is set as a diameter smaller than the cap 10 is interposed, The cylinder member 8 concerned, The inner side of the soft side leaf valve 4a on one side laminated on the first valve disk 9 is supported by the top portion 8a, and the soft side leaf valve 4a is set to open outwardly fixed on the inner side. The cylindrical portion 8b of the cylindrical member 8 has an outer diameter smaller than that of the top portion 8a, and two annular grooves 8c and 8d are provided on the outer periphery of the cylindrical portion 8b. The passage 8e provided in the thickness of the portion 8b and the annular groove 8f provided at the end of the cylindrical portion 8b communicate with the through hole 10b of the cap 10, and the annular groove 8d on the cap 10 side It communicates with the inside of the cylindrical portion 8b through a through hole 8g that penetrates the portion 8b.

  Further, a cylindrical spool 12 is mounted on the outer periphery of the cylindrical member 8 so as to be slidable in the vertical direction in FIG. Specifically, the spool 12 includes a large-diameter portion 12a formed with a large inner diameter so that the upper portion in FIG. 1 is in sliding contact with the outer periphery of the large-diameter top portion 8a of the cylindrical member 8, and the lower portion in FIG. Includes a small diameter portion 12b formed with a small inner diameter so as to be in sliding contact with the outer periphery of the small diameter cylindrical portion 8b of the cylindrical member 8, a flange 12c provided on the outer periphery, and a spool hole 12d penetrating the small diameter portion 12b. It is prepared for.

  When the spool 12 is mounted on the outer periphery of the cylindrical member 8 as described above, the pressure chamber R is interposed between the cylindrical member 8 and the spool 12 due to the balance between the outer peripheral shape of the cylindrical member 8 and the inner peripheral shape of the spool 12 described above. The pressure chamber R communicates with the annular groove 8 c of the cylindrical member 8. The annular groove 8c communicates with the through hole 10b of the cap 10 through the passage 8e and the annular groove 8f, and the through hole 10b communicates with the one chamber 41 through the annular groove 7a and the groove 7b of the spacer 7. R communicates with the one chamber 41 through these, and the pressure in the one chamber 41 is guided to the inside.

  Further, a coil spring 13 is interposed between the lower end of the flange 12c of the spool 12 in FIG. 1 and the bottom of the cap 10, and the spool 12 is urged upward by the coil spring 13 in FIG. A coil spring 15 is interposed between the upper end of 12c in FIG. 1 and a stopper 14 fitted in an annular groove 10c provided on the inner periphery of the cylindrical portion of the cap 10, and the spool 12 is shown in FIG. 1 It is energized downward. In this manner, the spool 12 is sandwiched from above and below by the pair of coil springs 13 and 15 and is positioned at a neutral position with respect to the tubular member 8 in a no-load state. In this state, the spool 12 is interposed via the annular groove 8d. The spool hole 12d is opposed to the through hole 8g, and the spool hole 12d and the through hole 8g are maintained in a communicating state. The spring for biasing the spool 12 may be a spring having a different structure, such as a plate spring or a disc spring, in addition to the coil springs 13 and 15.

  Now, the soft side leaf valve 4b on the other side, the first valve disc 9, the soft side leaf valve 4a on the one side, the cylindrical member 8, the coil spring 15, the spool 12, the coil spring 13, the cap 10, which are configured in this way. The spacer 7, the hard side leaf valve 5 b on the other side, the second valve disc 3, and the hard side leaf valve 5 a on the one side are sequentially assembled to the small diameter portion 2 a provided at the lower end in FIG. These are fixed to the rod 2 by a piston nut 16 screwed to the lowermost end of the rod 2, and the first valve disc 9 and the second valve disc 3 are connected by the rod 2.

  The rod 2 includes a small diameter portion 2a, a vertical hole 2c that opens from the lower end in FIG. 1 of the small diameter portion 2a and faces the other chamber 42, and a horizontal hole 2d that opens from the side of the small diameter portion 2a and communicates with the vertical hole 2c. When each member is assembled as described above, the horizontal hole 2c faces the cylindrical portion 8b of the cylindrical member 8, and the through hole 8g passes through the hollow hole 2b. And communicated with the other chamber 42.

  Therefore, the one chamber 41 and the other chamber 42 communicate with each other through the hardware side flow path H including the hardware side ports 3a and 3b, and also communicate with each other through the software side ports 9a and 9b, the room 11, the through hole 8g, and the hollow hole 2b. The soft side flow path S is formed by the soft side ports 9a and 9b, the chamber 11, the through hole 8g, and the hollow hole 2b.

  Further, since the pressure of the one chamber 41 led to the pressure chamber R acts on the spool 12 and the pressure of the other chamber 42 led to the chamber 11 acts, the inner edge of the large diameter portion 12a and the inner edge of the small diameter portion 12b 1 is applied to the spool 12 by the pressure in the one chamber 41, and the pressure in the other chamber 42 acts on the spool 12 as a pressure receiving area. A force in the direction of pushing up in FIG.

  When the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the force that pushes down the spool 12 overcomes the urging force of the coil spring 13 and the spool 12 moves from the neutral position downward in FIG. The hole 8g does not face the spool hole 12d, and the through hole 8g is closed by the inner surface of the spool 12, so that the soft-side flow path S is blocked. Further, when the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the force that pushes up the spool 12 overcomes the urging force of the coil spring 15 and the spool 12 moves upward from the neutral position in FIG. 8 g does not face the spool hole 12 d and the through hole 8 g is closed by the inner surface of the spool 12, and in this case, the soft-side flow path S is also blocked. That is, the on-off valve 6 includes a cylindrical member 8 provided with a through hole 8g, a spool 12 that is slidably mounted on the outer periphery of the cylindrical member 8 in the axial direction, and opens and closes the through hole 8g. The coil springs 13 and 15 as energizing springs and urging means for applying a differential pressure between the one chamber 41 and the other chamber 42 to the spool 12 are provided. A pressure chamber R for applying the pressure of the chamber 41 and a chamber 11 for applying the pressure of the other chamber 42 are configured.

  Next, the operation of the valve structure configured as described above will be described. First, when the shock absorber is in the extension stroke and the second valve disk 3 as a piston moves upward in FIG. 1 with respect to the cylinder 1, the pressure in the one chamber 41 increases, and the hydraulic oil in the one chamber 41 becomes An attempt is made to move into the other chamber 42 through the one soft side port 9a and the one hard side port 3a.

  When the piston speed that is the expansion / contraction speed of the shock absorber is in the low speed region, the working fluid does not deflect the one side soft side leaf valve 4a and the one side hard side leaf valve 5a, and the leaf valves 4a, 5a passes through a notch provided on one or both outer peripheries of 5a, or a well-known orifice (not shown) formed by stamping a valve seat provided on the first valve disc 9 or the second valve disc 3 on which the seat 5a is seated. The one chamber 41 moves to the other chamber 42.

  When the piston speed reaches the middle speed region, the working fluid is opened by bending the one side soft side leaf valve 4a and the one side hard side leaf valve 5a together. And the one side 41 passes from the one side hard side port 3a to the other side chamber 42, but the amount of bending of the one side soft side leaf valve 4a is larger than the amount of bending of the one side hard side leaf valve 5a, Since the soft side port 9a is opened larger than the hard side port 3a, when the piston speed is in the medium speed region, the pressure loss due to the soft side leaf valve 4a on one side is dominant, and the shock absorber is mainly used. A damping force is generated by the soft side leaf valve 4a on one side.

  Further, when the piston speed is in the low / medium speed region, the predetermined amount is set so that the pressure in the one chamber 41 does not exceed the pressure in the other chamber 42 by a predetermined amount. In the case of the speed region, the spool 12 cannot move greatly downward in FIG. 1 against the urging force of the coil spring 13, and even if it is positioned at the neutral position or moved, the spool hole 12d is inserted into the through hole 8g. The soft-side flow path S is maintained in an open state.

  Therefore, the damping characteristics of the shock absorber (the relationship between the damping force and the piston speed) are determined by the orifice when the piston speed is in the low speed region, and mainly when the piston speed is in the medium speed region. This is determined by the soft-side leaf valve 4a. By setting the rigidity of the soft-side leaf valve 4a low, the slope of the damping characteristic in the medium speed region is reduced as shown in FIG. The generated damping force can be set low.

  On the other hand, the speed of the piston 1 reaches the high speed region, and the difference between the pressure in the one chamber 41 and the pressure in the other chamber 42 increases, and the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount. As a result, the thrust force that presses the spool 12 downward in FIG. 1 due to the differential pressure between the one chamber 41 and the other chamber 42 exceeds the force of the coil spring 13, and the spool 12 is pushed downward from the neutral position in FIG. Since the through-hole 8g is blocked by the inner surface of the lever, the soft-side flow path S is cut off.

  Then, after the piston speed reaches the high speed region, the working fluid passes only through the open hard side port 3a and moves from the one chamber 41 to the other chamber 42. A damping force is generated by the hard side leaf valve 5a on one side.

  Therefore, when the speed of the piston 1 is in the high speed region, the damping characteristic of the shock absorber (the relation of the damping force to the piston speed) is determined by the hard side leaf valve 5a on one side, as shown in FIG. Thus, the characteristic of the soft side leaf valve 4a is switched to the characteristic of the hard side leaf valve 5a at the boundary between the medium speed and the high speed, and the shock absorber generates a high damping force.

  On the other hand, when the shock absorber is in the compression stroke and the second valve disc 3 moves downward in FIG. 1 with respect to the cylinder 1, the working fluid in the other chamber 42 flows into the other soft side port 9b and It tries to move into the one chamber 41 through the hard side port 3b on the other side, and resistance is given to the flow of this working fluid by the soft side leaf valve 4b and the hard side leaf valve 5b on the other side. appear. When the shock absorber is in the compression stroke, when the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the spool 12 resists the urging force of the coil spring 15 from the neutral position in FIG. The soft side flow path S is shut off.

  That is, when the shock absorber is in the compression stroke, as in the case where the shock absorber is in the expansion stroke, as shown in FIG. 2, when the piston speed is in the low speed region, the working fluid is on the other side soft side leaf valve. Without bending the 4b and the hard side leaf valve 5b on the other side, notches provided on the outer periphery of one or both of these leaf valves 4b and 5b, or the first valve disc 9 or the second valve disc 3 on which they are seated Since it moves from the other chamber 42 to the other chamber 41 through a well-known orifice (not shown) formed by being stamped on the valve seat provided in the valve seat, the damping characteristic of the shock absorber in this case is determined by the orifice. . Further, when in the middle speed region, the damping characteristic of the shock absorber is mainly determined by the soft side leaf valve 4b on the other side. Since S is closed, it is determined by the hard side leaf valve 5b on the other side, and the characteristic of the soft side leaf valve 4b is switched from the characteristic of the soft side leaf valve 4b to the characteristic of the hard side leaf valve 5b at the boundary between the medium speed and the high speed. Will generate a high damping force.

  As described above, in the valve structure of the shock absorber according to the present embodiment, when the piston speed is in the medium speed region, the piston speed is reduced when the piston speed reaches the high speed region while keeping the damping force low. The damping force can be made larger than when it is in the middle speed range, and even when the piston speed reaches the high speed range, the damping force will not be insufficient, vibration will be sufficiently suppressed, and the ride comfort in the vehicle Can be improved.

  In addition, in a situation where the amplitude at which the shock absorber expands or contracts most is large and the piston speed reaches the high speed region, the damping force generated by the shock absorber can be increased. The speed can be quickly reduced, and the impact at the time of maximum expansion or contraction can be reduced.

  Furthermore, since the soft side leaf valves 4a and 4b and the hard side leaf valves 5a and 5b do not affect each other in the damping characteristics even if the setting is changed, tuning of the damping characteristics when the piston speed is in the low / medium speed region. When the piston speed is in the high speed range, the tuning of the damping characteristic is facilitated, and the degree of freedom in design is greatly improved.

  In addition, this valve structure does not require various devices such as a sensor for detecting the piston speed, a motor for driving the valve, and a control device for controlling the motor. Absent.

  Since the first valve disk 9 and the second valve disk 3 are provided, the soft side valve 4 and the hard side valve 5 can be easily installed, and the structure of each valve disk is simplified. .

  When the damping characteristic is shifted from the characteristics of the soft-side leaf valves 4a and 4b to the characteristics of the hard-side leaf valves 5a and 5b, when the piston speed reaches from the medium speed to the high speed range, each spool 12 rapidly opens the through hole 8g. If it is set to close so as to gradually reduce the flow path area as the piston speed increases after reaching the high speed range, as shown in FIG. 3, the soft-side leaf valve 4a is not closed. , 4b can be changed gradually so that the characteristics of the hard-side leaf valves 5a, 5b are gradually changed, so that the damping force does not change abruptly. There is no sense of incongruity due to a sudden change in damping force or a shock is felt, and the spool 12 collides with the cap 10 or the top 8a of the cylindrical member 8 vigorously to generate an abnormal noise. Can be prevented Rukoto, it is possible to improve even more ride comfort.

  It should be noted that a predetermined amount that the pressure of the one chamber 41 should exceed the pressure of the other chamber 42 when the spool 12 closes the soft-side flow path S during the expansion operation of the shock absorber, and the spool 12 is soft during the compression operation of the shock absorber. The predetermined amount that the pressure in the other chamber 42 at the time of closing the side flow path S should exceed the pressure in the one chamber 41 is not necessarily set to be the same.

  When the damping characteristic is changed only during the extension operation of the shock absorber, the coil spring 15 that pushes the spool 12 downward is abolished as in the valve structure of a modification of the embodiment shown in FIG. Thus, until the spool 12 is energized only by the coil spring 13 and the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the through hole 8g provided at the lower end of the cylindrical member 8 is set not to be closed. Just keep it. In this case, since the damping characteristic is changed only during the extension operation, the soft side port 9b on the other side and the soft side leaf valve 4b on the other side are unnecessary and are eliminated. In this modified example, the pressure member R formed between the cylindrical member 8 and the spool 12 is opened from the first valve disk 9 of the rod 2 from above in FIG. The pressure of the one chamber 41 is introduced through a pilot passage 17 that is provided in the pilot passage 17 and communicates with the passage 8 h that communicates with the pressure chamber R. Therefore, the spacer 7 is not provided with an annular groove and a groove, and the cap 10 is not provided with a through hole. As described above, the pilot passage may be provided in the rod 2 to the pressure chamber R to guide the pressure in the one chamber 41.

  Further, when the damping characteristic is changed only during the compression operation of the shock absorber, the coil spring 13 for pushing the spool 12 upward is eliminated as in the valve structure of another modification of the embodiment shown in FIG. Then, until the spool 12 is urged only by the coil spring 15 and the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the through hole 18a provided at the upper end of the cylindrical member 18 is set not to be closed. You just have to. In this case, since the damping characteristic is changed only during the compression operation, the soft side port on the expansion side and the soft side leaf valve are unnecessary and are eliminated, and it is necessary to provide any member between the first valve disk 9 and the cylindrical member 18. Therefore, the cylindrical member 18 is integrated with the first valve disk 9. In this modified example, since the cylindrical member 18 is integrated with the first valve disk 9, the first valve disk is connected to the pressure chamber R formed between the cylindrical member 18 and the spool 12. The pressure in the one chamber 41 is introduced through a pilot passage 20 provided from 9 to the tubular member 18.

  As described above, even when the damping characteristic is changed only during the extension operation or only during the compression operation of the shock absorber, when the piston speed is in the middle speed region during the operation, the damping force is reduced. When the piston speed reaches the high speed range while keeping it low, the damping force can be increased more than when the piston speed is in the medium speed range, and the damping force is insufficient even when the piston speed reaches the high speed range. Therefore, the vibration is sufficiently suppressed, the riding comfort in the vehicle can be improved, the piston speed can be quickly reduced, and the impact at the time of maximum expansion or contraction can be alleviated.

  Furthermore, the soft side leaf valve and the hard side leaf valve do not affect each other in the damping characteristics even if the setting is changed, so the tuning of the damping characteristics and the piston speed are in the high speed range when the piston speed is in the low to medium speed range. Therefore, the tuning of the damping characteristics can be facilitated, and the degree of freedom in design can be greatly improved.

  In addition, this valve structure does not require various devices such as a sensor for detecting the piston speed, a motor for driving the valve, and a control device for controlling the motor. Absent.

  Next, a valve structure according to another embodiment will be described. In the valve structure of the other embodiment, the arrangement of the spools is different from the valve structure of the above-described one embodiment.

  Specifically, in one embodiment, the cylindrical spool 12 is slidably mounted on the outer periphery of the cylindrical members 8 and 18 provided in the room 11, but the valve structure of the other embodiments is used. In this case, as shown in FIG. 6, the spool 22 is slidably accommodated in the hollow hole 2b of the rod 2, and the other configuration is the same as that of the valve structure of the embodiment.

  Therefore, in the following description, in order to avoid duplication of explanation, only the portions where the valve structure of the other embodiment is different from the valve structure of one embodiment will be described in detail, and the same reference numerals will be used for similar members. The detailed description will be omitted as it is attached only.

  In the valve structure according to another embodiment, the spool 22 is slidably accommodated in the vertical hole 2c of the hollow hole 2b. The vertical hole 2c in the hollow hole 2b is opened from the lower end in FIG. 6 that is the tip of the rod 2, and the horizontal hole 2d extends from the middle to communicate with the outside of the rod 2. Further, the horizontal hole 2d faces the cylinder portion 26a of the cylinder member 26 accommodated in the room 11, and communicates with the inside of the room 11 through a notch 26b provided at the lower end of the cylinder portion 26a. Therefore, the chamber 11 is communicated with the other chamber 42 through the hollow hole 2b as in the valve structure of the embodiment, and the hollow hole 2b is connected to the soft-side flow path S as in the valve structure of the embodiment. Form a part of

  Returning to the rod 2, the pilot horizontal hole 2e that opens from the top in FIG. 6 through the first valve disk 9 and communicates with the one chamber 41 communicates with the pilot horizontal hole 2e and the bottom of the vertical hole 2c in the hollow hole 2b. Pilot vertical hole 2f.

  The spool 22 has a cylindrical shape with a top and a middle portion 22b having a large outer diameter portion 22b in sliding contact with the inside of the vertical hole 2c of the hollow hole 2b. The spool 22 rises from the top of the main body 22a and enters the pilot vertical hole 2f. And a shaft 22c that is slidably inserted. The pair of coil springs 23 and 24, which are also accommodated in the vertical hole 2c and sandwich the large outer diameter portion 22b, are neutral in the vertical hole 2c. Is positioned. Specifically, the coil spring 23 is interposed between the bottom of the vertical hole 2 c and the upper end of the large outer diameter portion 22 b of the spool 22, and the coil spring 24 is connected to the lower end of the large outer diameter portion 22 b of the spool 22. These coil springs 23 and 24 are interposed between the stop ring 25 fitted in the middle of the vertical hole 2c and urge the spool 22 from above and below to oppose each other.

  Further, the large outer diameter portion 22b is provided with a spool hole 22d that faces the lateral hole 2d in the neutral position and communicates the inside and outside of the spool 22, and when the spool 22 moves upward or downward from the neutral position. The spool hole 22d cannot face the horizontal hole 22d, and the soft side flow path S is blocked.

  Further, a through hole 22e penetrating the wall thickness is provided above the large outer diameter portion 22b of the main body 22a of the spool 22 in FIG. 6, and is within the vertical hole 2c and from the large outer diameter portion 22b of the spool 22. A configuration is adopted in which the upper side is not blocked, and a shaft 22c having a smaller diameter than the large outer diameter portion 22b of the spool 22 is provided and inserted into the pilot vertical hole 2f communicating with the one chamber 41. Thus, the pressure receiving area that receives the pressure of the one chamber 41 that acts to push the spool 22 downward and the pressure of the other chamber 42 that acts to push the spool 22 upward can be defined as the cross-sectional area of the shaft 22a. The area can be set small. Since the spring constant of the coil springs 23 and 24 can be reduced by reducing the pressure receiving area, the valve structure can be embodied in a shock absorber having a rod with a small rod diameter. ing. The shaft 22c and the through hole 22e can be eliminated, and the pressure of the one chamber 41 can be applied to the entire upper surface side of the spool 22, and the pressure of the other chamber 42 can be applied to the entire lower surface side of the spool 22.

  Further, in this embodiment, a large outer diameter portion 22b is provided in the middle portion of the main body 22a of the spool 22 and functions as a spring receiver for the coil springs 23 and 24 and other than the large outer diameter portion 22b of the main body 22a. Although the centering of the coil springs 23 and 24 is performed at the part, the entire body 22a may be slidably contacted with the vertical hole 2c. Of course, a spring other than the coil springs 23 and 24 may be used.

  In the valve structure according to another embodiment configured as described above, when the moving speed of the second valve disk 3 with respect to the cylinder 1 is low and medium speed, the spool 22 does not move greatly from the neutral position, Even if it moves, the spool hole 22 is opposed to the horizontal hole 2d, and the soft-side flow path S is not blocked.

  On the other hand, when the moving speed of the second valve disc 3 with respect to the cylinder 1 becomes high and the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the pressure difference between the one chamber 41 and the other chamber 42 is caused. The thrust force that pushes down the spool 22 in FIG. 6 overcomes the urging force of the coil spring 24, and the spool 22 moves downward to block the soft side flow path S. On the contrary, when the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount, the thrust that pushes up the spool 22 in FIG. 6 due to the differential pressure between the other chamber 42 and the one chamber 41 overcomes the urging force of the coil spring 23. 22 moves upward and the soft side flow path S is interrupted | blocked.

  Therefore, even in the valve structure according to another embodiment, the same operation as the valve structure according to the embodiment is performed because the same operation as the valve structure according to the embodiment is exhibited. In addition, in the valve structure of this other embodiment, the spool 11 is not accommodated in the chamber 11 but the structure accommodated in the hollow hole 2b of the rod 2 is adopted. 11 does not need to ensure vertical movement in the drawing of the spool, and has the advantage that the overall length of the valve structure can be shortened.

  Further, when the damping characteristic is changed only during the extension operation of the shock absorber, the coil spring 23 for pushing the spool 22 downward is abolished as in the valve structure of a modification of the other embodiment shown in FIG. Then, until the spool 22 is energized only by the coil spring 24 and the pressure in the one chamber 41 exceeds the pressure in the other chamber 42 by a predetermined amount, the lateral hole 2d is not closed by the large outer diameter portion 22b. Just keep it. In this case, since the damping characteristic is changed only during the extension operation, the soft side port 9b on the other side and the soft side leaf valve 4b on the other side are unnecessary and are eliminated. In this modified example, since it is not necessary to house the coil spring 23 between the upper end of the large outer diameter portion 22b and the bottom portion of the vertical hole 2c, the entire upper half of the main body 22a in FIG. Is the large outer diameter portion 22b.

  Further, when the damping characteristic is changed only during the compression operation of the shock absorber, the coil spring 24 for pushing the spool 22 upward is abolished as in the valve structure of another modification of the embodiment shown in FIG. Then, the spool 22 is energized only by the coil spring 23, and the large outer diameter portion 22b is set so as not to close the lateral hole 2d until the pressure in the other chamber 42 exceeds the pressure in the one chamber 41 by a predetermined amount. Just keep it. In this case, since the damping characteristic is changed only during the compression operation, the soft side port on the extension side and the soft side leaf valve are unnecessary and abolished, and it is necessary to provide any member between the first valve disk 9 and the cylindrical member 26. Therefore, the first valve disk 9 may be integrated with the cylindrical member 26.

  As described above, even when the damping characteristic is changed only during the extension operation or only during the compression operation of the shock absorber, when the piston speed is in the middle speed region during the operation, the damping force is reduced. When the piston speed reaches the high speed range while keeping it low, the damping force can be increased more than when the piston speed is in the medium speed range, and the damping force is insufficient even when the piston speed reaches the high speed range. Therefore, the vibration is sufficiently suppressed, the riding comfort in the vehicle can be improved, the piston speed can be quickly reduced, and the impact at the time of maximum expansion or contraction can be alleviated.

  Furthermore, the soft side leaf valve and the hard side leaf valve do not affect each other in the damping characteristics even if the setting is changed, so the tuning of the damping characteristics and the piston speed are in the high speed range when the piston speed is in the low to medium speed range. Therefore, the tuning of the damping characteristics can be facilitated, and the degree of freedom in design can be greatly improved.

  In addition, this valve structure does not require various devices such as a sensor for detecting the piston speed, a motor for driving the valve, and a control device for controlling the motor. Absent.

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

  In addition, the valve structure of the present invention can be embodied not only in the damping valve on both sides of the expansion of the piston portion of the shock absorber, but also in the damping valve only on the expansion side or only on the compression side as described above. Is possible. In the above description, one chamber 41 is described as an extension side chamber on the upper side of the shock absorber and the other chamber 42 is defined as a pressure side chamber on the lower side of the shock absorber. One chamber may be an extension chamber of the shock absorber and the other chamber may be a pressure side chamber of the shock absorber. Furthermore, when the shock absorber is set as a double cylinder shock absorber having a reservoir outside the cylinder and includes a base valve, the valve structure of the present invention can be embodied in the base valve portion. In this case, the first valve disc 9 and the second valve disc 3 may be connected by using a rod-like member as a rod instead of a piston rod, and a buffer valve functioning as a damping force generating element that generates a damping force. Of course, it is possible to apply to. That is, when the valve structure is embodied in the base valve portion, one chamber may be one of the pressure side chamber or the reservoir chamber and the other chamber may be the other of the pressure side chamber or the reservoir chamber. Furthermore, the valve structure can be embodied in both the piston part and the bale valve part of the shock absorber.

  Furthermore, as described above, the soft side valve 4 and the hard side valve 5 may use a damping valve other than the leaf valve.

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

The present invention is applicable to a shock absorber valve.

DESCRIPTION OF SYMBOLS 1 Cylinder 2 Rod 2a Small diameter part 2b in a rod Hollow hole 2c in a rod 2d Vertical hole in a rod 2d Horizontal hole in a rod 2e Pilot horizontal hole in a rod 2f Pilot vertical hole in a rod 3 Second valve disk 3a Hard side port 3b on one side The other Side hard side port 4 soft side valve 4a one side soft side leaf valve 4b other side soft side leaf valve 5 hard side valve 5a one side hard side leaf valve 5b other side hard side leaf valve 6 open / close valve 7 spacer 7a Annular groove in spacer 7b Groove 8, 18, 26 in spacer Cylindrical member 8a Top part 8b in cylindrical member, 26a Cylindrical part 8c in cylindrical member, 8d Annular groove 8e in cylindrical member, 8h Passage 8f in cylindrical member Annular groove in cylindrical member 8g, 18a Through hole 9 First valve disc 9a One side soft side port 9b The other side soft side port 10 Cap 10a Rod insertion hole 10b in cap Through hole 10c in cap Annular groove 12, 22 in cap Spool 12a Large diameter portion in spool 12b Small-diameter portion 12c in the spool Flange 12d, 22d in the spool Spool hole 13, 15, 23, 24 in the spool 14 Coil spring 14 as a spring Stopper 16 Piston nut 17, 20 Pilot passage 18 Through hole 22a in the cylindrical member Main body 22b in the spool Spool Large outer diameter portion 22c shaft 22e in spool 25e through hole 25 in spool stop ring 26b notch 41 in cylindrical member one chamber 42 other chamber H hard side flow path S soft side flow path

Claims (7)

A first valve disk having a soft-side flow path communicating between the one chamber and the other chamber separated in the shock absorber; and the one chamber and the other separated in the shock-absorber in parallel with the soft-side flow path A second valve disk having a hard side flow path communicating with the chamber, a soft side valve for opening and closing the soft side flow path, a hard side valve for opening and closing the hard side flow path, and the pressure in one chamber is A valve structure comprising an on-off valve that closes a soft-side flow path when the pressure exceeds a predetermined amount. An annular first valve disk having a soft-side flow path communicating between the one chamber and the other chamber separated in the shock absorber, and one chamber separated in the shock-absorber in parallel with the soft-side flow path An annular second valve disk having a hard side flow path communicating with the other chamber, a soft side valve for opening and closing the soft side flow path, a hard side valve for opening and closing the hard side flow path, and a first valve disk A rod that connects the first and second valve discs, and a cylindrical cap that is mounted on the outer periphery of the rod and that fits on the outer periphery of the first valve disc to form a chamber between the first valve disc, When the pressure in the chamber exceeds the pressure in the other chamber by a predetermined amount, there is an open / close valve that closes the soft-side flow path. The soft-side flow path has a hollow hole provided in the rod; Features formed with side port Valve structure to be. An annular first valve disk having a soft-side flow path communicating between the one chamber and the other chamber separated in the shock absorber, and one chamber separated in the shock-absorber in parallel with the soft-side flow path An annular second valve disk having a hard side flow path communicating with the other chamber, a soft side valve for opening and closing the soft side flow path, a hard side valve for opening and closing the hard side flow path, and a first valve disk And a rod that connects the second valve disc, and a cylindrical cap that is mounted on the outer periphery of the rod and that fits on the outer periphery of the first valve disc to form a chamber between the first valve disc and The hard side flow path is provided in the second valve disk, and is formed by one side hard side port communicating the one chamber and the other chamber and the other side hard side port parallel to the one side hard side port. The hard side valve is the second One side hard side leaf valve that is stacked on the other chamber side of the lube disc and opens and closes the one side hard side port and the other side that is stacked on the one chamber side of the second valve disc and opens and closes the other side hard side port A hard-side leaf valve, a soft-side flow path provided in the rod, a chamber, a soft-side port provided on the first valve disk and communicating between the one chamber and the chamber, and the other The soft side leaf on one side is formed with the soft side port on the other side in parallel with the soft side port on the side, and the soft side valve is stacked on the room side of the first valve disc to open and close the soft side port on the one side A valve and a soft leaf valve on the other side that opens and closes the soft port on the other side and is stacked on the one side of the first valve disc, and the pressure in the one chamber exceeds the pressure in the other chamber by a predetermined amount. Valve structure characterized in that a closing valve which closes the soft channel when that when with close soft passage pressure in the other chamber exceeds the pressure in one chamber a predetermined amount. The on-off valve is mounted on the outer periphery of the rod and is accommodated in the room and divides the soft flow path, a through hole provided in the cylindrical member for communicating the soft flow path, and the outer periphery of the cylindrical member in the axial direction. A spool that is slidably mounted to open and close the through hole, a spring that biases the spool in a direction to open the through hole, and a spool that biases the spool in a direction to close the through hole by a differential pressure between the one chamber and the other chamber The valve structure according to claim 2, further comprising an urging means. The on-off valve is mounted on the outer periphery of the rod, is accommodated in the room and divides the soft flow path, and also supports the inner periphery of one soft side leaf valve mounted on the outer periphery of the rod, and the cylindrical member A through hole for communicating the soft flow path, a spool that is slidably mounted on the outer periphery of the cylindrical member in the axial direction, a spool hole that is provided in the spool and faces the through hole in a neutral position, and a spool A pair of springs for biasing the two chambers from the opposite ends, and biasing means for applying the pressure of one chamber from one end of the spool and the pressure of the other chamber from the other end of the spool. The valve structure according to claim 3, wherein: The on-off valve is slidably inserted into the hollow hole of the rod to open and close the soft flow path, a spring that biases the spool in the direction to open the soft flow path, and the differential pressure between the one chamber and the other chamber The valve structure according to claim 2, further comprising: an urging unit that urges the spool in a direction to close the soft flow path facing the spring. The on-off valve includes a spool that is slidably inserted into the hollow hole of the rod, a spool hole that is provided in the spool and opens the soft flow path at the neutral position, and urges the spool from both ends to the neutral position. 4. A pair of springs for positioning, and biasing means for applying pressure in one chamber from one end of the spool and applying pressure in the other chamber from the other end of the spool. Valve structure.

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