JP6468016B2 - Shock absorber - Google Patents

Description

  The present invention relates to a shock absorber, and particularly relates to a shock absorber provided with a damping force adjusting mechanism.

  Some shock absorbers (shock absorbers) mounted on vehicles have a damping force adjusting mechanism. This mechanism can adjust the damping force generated by the piston because the damping force is determined uniquely with respect to the operating speed of the piston, and it is impossible to satisfy the contradictory riding comfort and steering stability. Various types are known. For example, in Patent Document 1 below, “With a conventional shock absorber equipped with a damping force adjusting valve, it is difficult to obtain a flat and flat damping force characteristic with a small outflow by adjusting the damping characteristic, for example. In these cases, it is inevitable to work uneven or unstable. It is necessary to allow the buffer to behave smoothly to allow any different types of adjustments ”(paragraph of Patent Document 1). In order to solve this problem, “it has a valve seat having a valve hole and a valve body that opens and closes the valve hole, and one surface of the valve body is operated via the valve hole. A buffer configured to apply a force in the opening direction of the liquid and a force in the closing direction to the other surface to generate a damping force according to the stroke of the valve body and in accordance with the size of the stroke. With the stroke of the valve An inner damping portion and an outer damping portion that act simultaneously to generate the damping force, and the inner damping portion and the outer damping portion have a damping portion area whose size changes simultaneously with the stroke; The damping force generated by each attenuating part changes stepwise or continuously in different magnitudes according to the changing speed of the attenuating part area, and the working liquid flows from the inner attenuating part to the outer attenuating part. A damping force adjusting valve for a shock absorber has been proposed (described in the paragraph [0012]), in which a damping force is generated only in the inner damping portion and the outer damping portion.

Japanese Patent No. 3655489

  In the damping force adjusting valve described in the above-mentioned patent document, it has two damping parts consisting of an outer damping part and an inner damping part that act simultaneously with the stroke of the valve body to generate damping force, and these damping parts The damping part area changes with the stroke, and the magnitude of the damping force generated by each damping part changes, so that the damping force is continuously changed according to the magnitude of the stroke. However, since the two damping parts are arranged in series, when the valve body makes a large stroke in the valve opening direction, the damping forces of the two damping parts will be combined, and the sufficient damping force The reduction effect cannot be expected. In addition, since the two damping parts operate simultaneously with the stroke of the valve body and the seal part of the inner damping part is configured by the overlap of the valve body and the valve seat, the geometrical tolerance limits of the valve body and the valve seat (Flatness, coaxiality) is small, and the damping force characteristic tends to vary.

  Therefore, an object of the present invention is to provide a shock absorber having a damping force adjusting mechanism that has a large damping force reduction effect and can secure a stable desired damping force characteristic.

  In order to achieve the above object, the present invention provides a cylinder that contains a working fluid, a piston that slides within the cylinder, a piston rod that is connected to the piston, and a fluid that flows through the piston within the cylinder. And a damping force adjusting mechanism for controlling a working fluid to adjust a damping force, wherein the damping force adjusting mechanism includes a case in which a flow path communicating with the cylinder is formed and joined to the cylinder. A valve seat member provided in the flow path in the case, and a valve that blocks the flow path when seated on the valve seat member and communicates the flow path when separated from the valve seat member A member, an urging member that urges the valve member in a direction in which the valve member is seated on the valve seat member, an adjustment valve member that is interposed between the valve seat member and the valve member and is supported by the valve member The valve member is formed so as to be opposed to the outside of the valve seat member. The adjustment valve member is disposed so as to be able to contact the valve seat member and the valve seat portion, and is formed with a communication passage that opens inside the valve seat member. The plate-like valve body and the valve seat portion constitute a first damping portion, and the plate-like valve body and the valve seat member constitute a second damping portion. In the initial position, the plate-like valve body is in contact with the valve seat portion and the valve seat member, and the valve member in a direction in which the plate-like valve body is separated from the valve seat member. As the stroke increases, the plate-like valve body sequentially separates from the valve seat portion and the valve seat member, and the communication path, and the first between the plate-like valve body and the valve seat portion, The flow path communicates with the gap to operate the first damping part, and the second gap between the plate-shaped valve body and the valve seat member is operated. Serial passage the second damping unit is activated in communication, the opening area of the flow path in accordance with the increase of the stroke of the valve member is what is set to increase.

  In the above shock absorber, the plate-like valve body constituting the adjustment valve member is formed in a disc shape, and the displacement amount increases from a central portion of the plate-like valve body toward an outer peripheral edge portion. It is supported on the bottom surface of the valve member and is arranged so as to be able to contact the valve seat portion on one surface of the outer peripheral edge portion of the plate-shaped valve body, and on the other surface of the outer peripheral edge portion of the plate-shaped valve body. The valve seat member is disposed so as to be in contact with the valve seat member, and a gap is formed between one surface of the plate-like valve body and the valve seat portion, and the communication passage communicates with the gap. It is good to be the structure currently formed in the body.

  The communication passage formed in the plate-shaped valve body may be formed in at least one slit shape extending radially from a central portion of the plate-shaped valve body. Furthermore, the seat diameter of the valve seat portion formed on the valve member may be set to be larger than the seat diameter of the valve seat member.

  Since this invention is comprised as mentioned above, there exist the following effects. That is, in the shock absorber of the present invention, the damping force adjusting mechanism includes a case in which a flow path communicating with the cylinder is formed and joined to the cylinder, a valve seat member provided in the flow path in the case, and a valve A valve member that shuts off the flow path when seated on the seat member, and communicates the flow path when separated from the valve seat member; and a biasing member that biases the valve member in the direction of seating on the valve seat member; An adjustment valve member interposed between the valve seat member and the valve member and supported by the valve member. The valve member is formed so as to be opposed to the outside of the valve seat member. The adjustment valve member has a flexible plate-shaped valve body that is disposed so as to be in contact with the valve seat member and the valve seat portion and has a communication passage that opens inside the valve seat member. The plate-like valve body and the valve seat portion constitute a first damping portion, and the plate-like valve body and the valve seat member constitute a second damping portion, which is at the initial position. In this state, the plate-shaped valve body is in contact with the valve seat portion and the valve seat member, and the plate-shaped valve body increases in response to an increase in the stroke of the valve member in the direction in which the plate-shaped valve body separates from the valve seat member. The body sequentially moves away from the valve seat part and the valve seat member, and the flow path communicates through the communication path and the first gap between the plate-like valve body and the valve seat part, and the first attenuation part In addition, the flow path communicates via the second gap between the plate-shaped valve body and the valve seat member, the second damping portion is activated, and the flow path is increased in response to an increase in the stroke of the valve member. Since the opening area is set to increase, the damping force reduction effect is large, and a stable desired damping force characteristic can be ensured.

  Particularly, since the first and second attenuation portions have different attenuation portion areas, the attenuation force can be continuously changed, and the first and second attenuation portions are arranged in parallel. Therefore, even when the valve member strokes in the valve opening direction, it is not affected by the damping portion arranged on the inner side, and the damping force can be appropriately and sufficiently reduced. Moreover, since the plate-shaped valve member is flexible, it is not necessary to form a seal portion by overlapping the plate-shaped valve body, the valve seat portion, and the valve seat member, and the geometrical relationship between the two is not necessary. The allowable limit is large, and stable damping force characteristics can be secured.

  In the above shock absorber, the plate-like valve body constituting the adjusting valve member is formed in a disc shape, and the bottom surface of the valve member is increased so that the amount of displacement increases from the center portion of the plate-like valve body toward the outer peripheral edge portion. And is arranged so that it can come into contact with the valve seat on one surface of the outer peripheral edge of the plate-like valve body, and can come into contact with the valve seat member on the other surface of the outer peripheral edge of the plate-like valve body If the configuration is such that a gap is formed between one surface of the plate-shaped valve body and the valve seat portion, and a communication path is formed in the plate-shaped valve body so as to communicate with the gap, Therefore, a stable damping force characteristic can be easily secured.

  If the communication passage formed in the plate-shaped valve body is formed in at least one slit shape extending radially from the central portion of the plate-shaped valve body, the central portion of the plate-shaped valve body is formed on the bottom surface of the valve member. By simply supporting the gap, the gap can be easily communicated with the flow path. Furthermore, if the seating diameter of the valve seat part formed in the valve member is set larger than the seating diameter of the valve seat member, the first and second damping parts can be easily and reliably arranged in parallel. .

It is sectional drawing of the damping force adjustment mechanism with which the buffer which concerns on one Embodiment of this invention was mounted | worn. It is a top view of the adjustment valve member provided for one Embodiment of this invention. It is a top view which shows another aspect of the adjustment valve member provided to one Embodiment of this invention. It is sectional drawing which expands and shows a part of damping force adjustment mechanism with which one Embodiment of this invention is provided. It is sectional drawing which shows the operating state of the damping force adjustment mechanism which concerns on one Embodiment of this invention. It is sectional drawing which shows the operating state of the damping force adjustment mechanism which concerns on one Embodiment of this invention. It is a graph which shows the damping force characteristic of the buffer concerning one embodiment of the present invention as contrasted with the conventional characteristic.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a damping force adjusting mechanism mounted on a shock absorber according to an embodiment of the present invention. A cylindrical body 1 that contains a working fluid is composed of an outer cylinder 1a, an inner cylinder 1b, and a cylinder 1c. As shown by a two-dot chain line, a piston 2 that slides inside the cylindrical body 1 and a piston rod 3 that is connected to the piston 2 are provided. A first flow path F1 is formed between the inner cylinder 1b and the cylinder 1c, and a second flow path F2 is formed between the outer cylinder 1a and the inner cylinder 1b. In the cylinder 1c, an upper chamber UC and a lower chamber LC are formed on both sides of the piston 2, a base valve BV is disposed in the lower chamber LC at the bottom of the cylinder 1c, and a piston valve PV is disposed in the piston 2. Has been. Each valve is configured in the same manner as before, and has at least a one-way valve function that allows fluid flow from the lower side to the upper side at a predetermined fluid pressure or higher and blocks the reverse flow. Yes. Through this base valve BV, the lower chamber LC communicates with the second flow path F2, and the upper chamber UC communicates with the first flow path F1.

  A damping force adjusting mechanism DA is joined to the cylinder 1 and is connected to the first flow path F1 and the second flow path F2 as shown in FIG. Thus, the fluid in the upper chamber UC is discharged to the first flow path F1 and introduced into the damping force adjusting mechanism DA. And it is discharged | emitted from the damping-force adjustment mechanism DA to the 2nd flow path F2, and is introduce | transduced in the lower chamber LC via the base valve BV. The second flow path F2 functions as a so-called reservoir.

  In the damping force adjusting mechanism DA of this embodiment, the double cylinder-shaped case 10 is joined to the cylinder 1, and the solenoid assembly 40 is joined to the case 10 with the valve member 30 housed in the case 10. ing. The case 10 is disposed so as to surround the inner case 11 in which one opening end portion is liquid-tightly fitted to the inner peripheral surface of the cylindrical portion 1d that opens to the inner cylinder 1b. The outer casing 1a is joined to the outer cylinder 1a so as to communicate with the flow path F2, and the outer casing 12 has a flange 11a formed by expanding the diameter of the other opening end of the inner casing 11. It arrange | positions so that it may latch on the cyclic | annular step part 12a formed in the 12 inner peripheral surface. The stepped annular member 43 of the solenoid assembly 40 is in contact with the end surface of the flange portion 11a of the inner case 11 and is liquid-tightly fitted to the inner peripheral surface of the outer case 12, so that the outer peripheral surface of the outer case 12 is closed. A cylindrical fastening member 13 is screwed together so as to be integrated.

  A cylindrical valve seat member 21 is press-fitted into one open end portion of the inner case 11, and a valve member 22 is accommodated in the inner case 11 so as to be able to be seated in contact with the open end surface. Axial distance is slidably supported. As shown in FIG. 1, the valve member 22 is formed in a cup shape of a bottomed cylindrical body, a communication hole P0 is formed at the bottom, and a labyrinth groove is formed on the outer peripheral surface. Further, a valve seat member 23 formed in a hat shape of a bottomed cylindrical body with a gap in the radial direction and the axial direction with respect to the valve member 22 is loosely fitted in the cylindrical body of the valve member 22, and the inner case The flange portion 23a is locked to the annular step portion 11b formed on the inner peripheral surface of the valve 11, so that the predetermined axial distance with respect to the valve member 22 is maintained. A compression coil spring B1 is accommodated in the annular gap between the valve member 22 and the valve seat member 23, and is stretched between the bottom portion of the valve member 22 and the flange portion 23a of the valve seat member 23. A communication hole P1 is formed at the bottom of the valve seat member 23, and a first valve seat S1 is formed therearound. The valve member 22 supports an adjustment valve member 50, which will be described later.

  Further, a cylindrical support member 24 that supports the valve member 30 so as to be movable in the axial direction is accommodated in the inner case 11, and a flange portion 24 a formed at one end of the support member 24 is a flange portion 23 a of the valve seat member 23. It arrange | positions so that it may contact | abut. A compression coil spring B <b> 2 is accommodated in the annular gap between the valve member 30 and the valve seat member 23, and is stretched between the bottom portion of the valve seat member 23 and the large diameter portion 32 of the valve member 30. A communication hole P3 is formed in the radial direction on the side wall of the support member 24, and communication holes P4 and P5 are also formed in the radial direction on the side wall of the inner case 11. The valve member 30 of the present embodiment is a single member having a stepped rod shape, and is formed with an axial communication hole 33 and radial communication holes 34 and 35 communicating with the axial communication hole 33, but the communication hole 35 is omitted. It is good to do.

  A communication hole P2 having a diameter smaller than that of the large diameter portion 32 of the valve member 30 and larger than that of the intermediate portion of the valve member 30 is formed in the flange portion 24a of the support member 24, and a second valve seat S2 is formed around the communication hole P2. It is configured. The valve member 30 is held so that the large-diameter portion 32 can be seated on the second valve seat S2, and slidably held in the cylindrical body of the support member 24 via a bush 25 made of sintered metal, for example. In the state where the compression coil spring B <b> 2 is accommodated in the valve seat member 23, the flange portion 24 a of the support member 24 is disposed so as to contact the flange portion 23 a of the valve seat member 23. Thus, the valve member 30 has a first valve body portion V1 formed by the tip portion 31 of the valve member 30, and a second valve body portion V2 formed by the large diameter portion 32, which will be described later. As described above, the flow rate of the communication hole P1 can be controlled by the first valve body V1 and the first valve seat S1. The valve member 30 and the bush 25 are preferably set in a liquid tight fitting state so that fluid does not pass through.

  On the other hand, in the solenoid assembly 40, a cylindrical plunger 41 arranged so as to contact the rear end surface of the valve member 30 is slidable in a cylindrical plunger case 42 formed by metal deep drawing. In the accommodated state, the open end of the plunger case 42 is welded and joined to the small-diameter cylindrical portion 43 a of the stepped annular member 43 and is integrated with the stepped annular member 43. The stepped annular member 43 functions as a fixed core, and a tapered hole (medium diameter hole) 43b, a small diameter hole 43c, and a large diameter hole 43d are formed at the center thereof, and the body portion of the valve member 30 is formed in the small diameter hole 43c. Are loosely fitted, and the support member 24 is loosely fitted into the large-diameter hole 43d so that the fluid can pass through each minute gap.

  Further, a cylindrical fixed core 44 is disposed around the plunger case 42 and a cylindrical solenoid coil 45 is disposed around the fixed core 44. Then, together with a connector 47 electrically connected to the solenoid coil 45, a cylindrical solenoid case 46 for housing them is joined to the stepped annular member 43, and joined to the outer case 12 by the fastening member 13 as described above. The Since the plunger case 42 is filled with fluid and the pressure applied to both end faces of the plunger 41 is canceled out, the driving force for the plunger 41 is not influenced by the pressure of the fluid. Further, since the valve member 30 has a solid part instead of a cylindrical body, the fluid pressure in the valve seat member 23 is not transmitted to the plunger 41 as it is, and the flow path to the plunger 41 is the above-mentioned minute amount. Since it is squeezed by the gap, the inside of the plunger case 42 can be avoided from becoming a high pressure.

  Thus, in this embodiment, the flow path (F1) communicating with the cylindrical body 1 is formed and the case 10 joined to the cylindrical body 1, and the valve seat provided in the flow path (F1) in the case 10 The valve member 22 that shuts off the flow path when seated on the member 21 and the valve seat member 21 and communicates the flow path when separated from the valve seat member 21, and the valve member 22 sits on the valve seat member 21. Damping force provided with an urging member (compression coil spring B1) for urging in the direction to be moved, and an adjustment valve member 50 interposed between the valve seat member 21 and the valve member 22 and supported by the valve member 22 An adjustment mechanism DA is configured.

  The valve member 22 of the present embodiment has a valve seat portion 22a formed so as to face the outside of the valve seat member 21, as shown in an enlarged view in FIG. The adjusting valve member 50 is disposed so as to be able to contact the valve seat member 21 and the valve seat portion 22a, and is a flexible plate-like valve body in which a communication passage 52 that opens inside the valve seat member 21 is formed. 51, the plate-like valve body 51 and the valve seat portion 22a constitute a first damping part, and the plate-like valve body 51 and the valve seat member 21 constitute a second damping part. .

  In the initial position shown in FIGS. 1 and 4, the plate-like valve body 51 is in contact with the valve seat portion 22 a and the valve seat member 21 of the valve member 22, and the plate-like valve body 51 is separated from the valve seat member 21. As the stroke of the valve member 22 increases in the separating direction, the plate-like valve body 51 is sequentially separated from the valve seat portion 22a and the valve seat member 21, and the communication passage 52, the plate-like valve body 51, and the valve The flow path (F1) communicates with the seat portion 22a via the first gap G1 (shown in FIGS. 5 and 6) to operate the first damping portion, and the plate-like valve body 51 and the valve The flow path (F1) communicates with the seat member 21 via the second gap G2 (shown in FIG. 6), and the second damping portion is activated, so that the flow increases as the stroke of the valve member 22 increases. The opening area of the path (F1) is set to increase.

  As shown in enlarged views in FIGS. 2 and 4, the adjustment valve member 50 of the present embodiment is configured by a metal disc-shaped plate-shaped valve body 51 having flexibility, and the plate-shaped valve body 51 is configured as follows. The central portion 51a is supported on the bottom surface of the valve member 22 so that the amount of displacement increases from the central portion 51a toward the outer peripheral edge portion 51b. One surface of the outer peripheral edge portion 51b (indicated by a two-dot chain line in FIG. 2) (Hatching area in the frame) is arranged so as to be able to contact the annular valve seat portion 22a, and the other surface of the outer peripheral edge portion 51b (hatching area in the frame shown by a broken line in FIG. 2) is attached to the valve seat member 21. It arrange | positions so that contact | abutment is possible. In other words, the plate-like valve body 51 has one face of the outer peripheral edge 51b, the valve seat 22a is seated in the hatched area in the two-dot chain line frame in FIG. 2, and the other face of the outer peripheral edge 51b. Thus, the valve seat member 21 is arranged so as to be seated in the hatched area in the broken line frame of FIG.

  The plate-like valve body 51 has flexibility, and a mounting hole 51c (shown in FIGS. 2 and 4) formed in the center thereof is a convex portion 22b (shown in FIG. 4) formed on the bottom surface of the valve member 22. The first gap G1 is formed between the outer peripheral edge portion 51b and the valve seat portion 22a, as shown in FIGS. 5 and 6, so that the outer peripheral edge is supported by the valve member 22. A second gap G2 may be formed between the portion 51b and the valve seat member 21. Furthermore, a slit-like communication passage 52 extending radially from the central portion 51a (mounting hole 51c) of the plate-like valve body 51 is formed. 2 and 4, the seat diameter of the valve seat portion 22a formed on the valve member 22 (the center diameter D1 of the hatched area in the two-dot chain line frame shown in FIG. 2) is the valve seat member 21. Is set to be larger than the seating diameter (indicated by the center diameter D2 of the hatched area in the broken line frame shown in FIG. 2).

  Thus, as shown in FIG. 4, a regulating valve is formed so that a gap G3 is formed between one surface of the plate-like valve body 51 and the valve seat portion 22a, and the communication path 52 communicates with the gap G3. A member 50 is provided. As shown in FIG. 3, the plate-shaped valve body 51 is formed in the gap G3 by a pair of communication holes 53, 53 formed between the central portion 51a (mounting hole 51c) and the outer peripheral edge portion 51b. It is good also as comprising the communicating path which connects.

  Next, the overall operation of the shock absorber equipped with the damping force adjusting mechanism DA configured as described above will be described. For example, when the piston 2 starts to compress and lower in the lower chamber LC from the stopped state of FIG. 1, the fluid in the lower chamber LC moves to the upper chamber UC via the piston valve PV, and the first flow path F1. Are introduced into the valve member 22 and the valve seat member 23 through the valve seat member 21 and the communication holes P0 and P1 of the damping force adjusting mechanism DA, and discharged to the second flow path F2 through the communication holes P2 to P4. The When the pressure introduced from the first flow path F1 to the valve seat member 21 increases as the speed of the piston 2 increases, the valve member 22 separates from the valve seat member 21 against the biasing force of the compression coil spring B1. The fluid is then discharged from the gap between the two into the second flow path F2 through the communication hole P5. The damping force adjusting mechanism DA operates in the same manner when the piston 2 rises by compressing the inside of the upper chamber UC.

  Further, when the solenoid coil 45 of the damping force adjusting mechanism DA is excited, the plunger 41 is driven forward (moved to the left in FIG. 1), and the valve member 30 moves in the same direction against the biasing force of the compression coil spring B2. As the exciting current of the solenoid coil 45 increases, the tip end portion (first valve body portion V1) of the valve member 30 comes close to the first valve seat S1, and finally the first valve body portion. V1 is seated on the first valve seat S1. During this time, a pressure difference is generated on both sides of the bottom of the valve member 22 by the fluid introduced from the first flow path F1, and the valve member 22 is driven rightward in FIG. 1 against the urging force of the compression coil spring B1. The fluid is separated from the valve seat member 21, and the fluid is discharged from the gap between the two into the second flow path F2 through the communication hole P5.

  Then, by controlling the exciting current for the solenoid coil 45 during this period, first, the plate-like valve body is increased in response to an increase in the stroke of the valve member 22 in the direction in which the valve member 22 and thus the adjusting valve member 50 is separated from the valve seat member 21. When 51 is separated from the valve seat portion 22a and enters the state shown in FIG. 5, through the communication passage 52 and the first gap G1 formed between the plate-like valve body 51 and the valve seat portion 22a, As indicated by an arrow in FIG. 5, the fluid from the flow path (F1) flows in a direction (downward in FIG. 5) reaching the communication hole P5 (shown in FIG. 1), and the first attenuation section described above is activated.

  Subsequently, when the plate-like valve body 51 is also separated from the valve seat member 21 and is in the state shown in FIG. 6, the communication passage 52 and the first gap between the plate-like valve body 51 and the valve seat portion 22a. In addition to G1, through the second gap G2 formed between the plate-like valve body 51 and the valve seat member 21, the fluid from the flow path (F1) is shown in FIG. It flows in the direction (downward in FIG. 6) to reach P5 (shown in FIG. 1), and the above-described second damping section is activated. Thereafter, the opening area of the flow path (F1) according to the increase in the stroke of the valve member 22 Increases and the flow rate of the fluid passing therethrough increases.

  Thus, the flow rate of the fluid passing through the adjustment valve member 50 changes, and the damping force applied to the fluid in the first and second flow paths F1 and F2 is adjusted accordingly. For example, if the exciting current for the solenoid coil 45 is increased, the forward driving force for the plunger 41 is increased, and the flow rate of the fluid passing between the first valve body V1 and the first valve seat S1 is decreased. The generated damping force increases, and so-called hard damping force control is performed. On the other hand, when the exciting current for the solenoid coil 45 is decreased, the driving force for the plunger 41 is decreased, and the flow rate of the fluid passing between the first valve body V1 and the first valve seat S1 is increased. Therefore, the generated damping force is reduced, and so-called soft damping force control is performed. In any case, as shown in FIG. 7, this embodiment is compared with the damping force characteristic of the conventional device indicated by a broken line. According to this, it is possible to suppress an increase in damping force when the piston speed increases (reduce the damping force) and to secure a stable damping force characteristic.

  As described above, in the damping force adjusting mechanism DA of the present embodiment, the plate-shaped valve body 51 is provided in accordance with the increase in the stroke of the valve member 22 in the direction in which the adjusting valve member 50 is separated from the valve seat member 21. Sequentially separate from the valve seat portion 22a and the valve seat member 21, the flow path (F1) communicates through the communication passage 52 and the first gap G1 between the plate-like valve body 51 and the valve seat portion 22a. The first attenuating portion is activated and the flow path (F1) is communicated via the second gap G2 between the plate-like valve body 51 and the valve seat member 21 to activate the second attenuating portion. Since the opening area of the flow path (F1) is set to increase as the stroke of the valve member 22 increases, the damping force reduction effect is great and a stable desired damping force characteristic can be ensured. .

  Further, since the valve seat portion 22a and the valve seat member 21 are set to have different seating diameters, the damping portion area constituted by the plate-like valve body 51 and the valve seat portion 22a, the plate-like valve body 51 and the valve seat member 21 is different in the area of the attenuation portion. That is, since the first damping part and the second damping part configured by the regulating valve member 50 have different damping part areas, the damping force can be continuously changed. In addition, since the two damping parts are arranged in parallel, even when the valve member 22 strokes in the valve opening direction, the damping force is appropriately adjusted without being affected by the damping part arranged on the inner side. And it can fully reduce. In particular, since the plate-like valve body 51 is flexible, it is not necessary to form a seal portion by overlapping the plate-like valve body 51 with the valve seat portion 22a and the valve seat member 21, and geometrical allowance between them is not required. The limit is large and stable damping force characteristics can be secured.

DESCRIPTION OF SYMBOLS 1 Tubular body 2 Piston 3 Piston rod 10 Case 21, 23 Valve seat member 22, 30 Valve member 24 Support member 40 Solenoid assembly 41 Plunger 45 Solenoid coil 50 Adjustment valve member 51 Plate-shaped valve body 52 Communication path F1 1st flow path F2 2nd flow path S1 1st valve seat S2 2nd valve seat G1 1st gap G2 2nd gap V1 1st valve body part V2 2nd valve body part P0-P5 Communication hole

Claims (4)

  Damping that adjusts damping force by controlling the working fluid that flows through the piston in the tubular body, a piston that slides in the tubular body, a piston rod that is connected to the piston, and a piston rod that is connected to the piston In the shock absorber provided with the force adjusting mechanism, the damping force adjusting mechanism is provided in the flow path in the case where a flow path communicating with the cylindrical body is formed and joined to the cylindrical body. A valve member, a valve member that blocks the flow path when seated on the valve seat member, and communicates the flow path when separated from the valve seat member; and the valve member is connected to the valve seat member An urging member for urging in a seating direction; and an adjusting valve member interposed between the valve seat member and the valve member and supported by the valve member, wherein the valve member includes the valve seat A valve seat portion formed so as to be opposed to the outside of the member; A flexible plate-like valve body that is disposed so as to be able to contact the valve seat member and the valve seat portion and has a communication passage that is open inside the valve seat member; And the valve seat portion constitutes a first damping portion, and the plate-like valve body and the valve seat member constitute a second damping portion, and in the initial position, the plate-like valve body is the valve seat. The plate-like valve elements are sequentially brought into contact with the valve-seat member according to an increase in the stroke of the valve member in a direction in which the plate-like valve element is separated from the valve-seat member. The first passage is separated from the valve seat portion and the valve seat member, and the flow path communicates with the first passage between the plate passage and the valve seat portion. While the attenuating portion is operated, the flow path is communicated through the second gap between the plate-like valve body and the valve seat member, and the second attenuating portion is Dynamic and shock absorber, characterized in that the opening area of the flow path is set so as to increase with an increase in the stroke of the valve member.   The plate-like valve body constituting the adjustment valve member is formed in a disk shape, and is supported on the bottom surface of the valve member so that the amount of displacement increases from the central part of the plate-like valve body toward the outer peripheral edge part. And is disposed so as to be able to contact the valve seat portion on one surface of the outer peripheral edge portion of the plate-shaped valve body, and against the valve seat member on the other surface of the outer peripheral edge portion of the plate-shaped valve body. It arrange | positions so that contact is possible, the space | gap is formed between the one surface of the said plate-shaped valve body, and the said valve seat part, and the said communicating path is formed in the said plate-shaped valve body so that it may connect with this space | gap. The shock absorber according to claim 1.   The shock absorber according to claim 2, wherein the communication passage formed in the plate-shaped valve body is formed in at least one slit shape extending radially from a central portion of the plate-shaped valve body. .   The shock absorber according to claim 2 or 3, wherein a seating diameter of the valve seat portion formed on the valve member is set larger than a seating diameter of the valve seat member.

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