JP2009103285A - Damping valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a damping valve which can prevent the declining of damping force even if the buffer operates rapidly and at high speed. <P>SOLUTION: A damping valve V includes a hollow valve case 1 which has a port 1a to communicate with the inside and the outside at the middle side part, a first channel P1 which leads to the above port 1a upstream of one end 1b of the valve case 1, a second channel P2 which leads to the above port 1a as an upper stream of the other end 1c of the valve case 1, a first valve 2 which is formed of a first annular valve seat 3 formed on the way of the first channel P1 and the first valve seat 3 and a first valve body 4 to be separated and seated to the first valve seat 3, a second valve 5 which is formed of a second annular valve seat 6 arranged coaxially with the first valve seat 3 formed on the way of the second channel P2 and a second valve 7 which is separated and seated to the second valve seat 6, a bias means 22 to bias the first valve body 4 toward the first valve seat 3 through the second valve body 7 while biasing the second valve body 7 toward the second valve seat 6, the first fixed throttle 9 prepared upstream of the first valve 2 of the first channel P1 and a second fixed throttle 10 prepared upstream of the second valve 5 of the second channel P2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a damping valve.

  This type of damping valve is applied to, for example, a shock absorber mounted on a vehicle or the like, and functions as a damping force generation source that attenuates vibration generated in the vehicle body or steering.

  In particular, when the shock absorber is used for the purpose of attenuating the vibration generated in the steering of the two-wheeled vehicle, the same damping force is output on both the left and right sides with respect to the left and right vibration of the steering with respect to the neutral position of the shock absorber. Is required.

  By the way, as a method for equalizing the damping force on both the left and right sides of the shock absorber, one damping valve is used, and the above-mentioned damping valve is allowed to pass through the hydraulic oil in one direction even if the shock absorber operates in either the left or right direction. However, this complicates the hydraulic circuit and requires frequent use of check valves, leading to a complicated structure of the shock absorber and disadvantageous in terms of economy.

  Therefore, there is a proposal of a damping valve that does not cause the disadvantage of complicating the structure of the shock absorber even when applied to the shock absorber, and this proposed damping valve is a hollow with a port that communicates the inside and the outside on the intermediate side. A valve case, a first flow path leading to the port with one end side of the valve case as an upstream side, a second flow path leading to the other end side of the valve case with the port as an upstream side, and formed in the middle of the first flow path A first valve comprising an annular first valve seat and a first valve body seated on and away from the first valve seat, and an annular first valve formed in the middle of the second flow path and coaxially disposed on the first valve seat. A second valve composed of a two-valve seat and a second valve body that is attached to and detached from the second valve seat; and the second valve body is urged toward the second valve seat and the first valve is interposed via the second valve body. And an urging means for urging the body toward the first valve seat (see, for example, Patent Document 1).

In this damping valve, not only can the damping characteristics be set to be the same when the shock absorber is actuated on both the left and right sides, but also the hydraulic circuit of the shock absorber can be operated with respect to the damping valve. Since it can be applied to a shock absorber without being configured to be a one-way flow, the above disadvantages can be eliminated.
JP 2006-183864 A (FIG. 1)

  As described above, the proposed damping valve is excellent in that the cost can be reduced without complicating the circuit of the shock absorber, but has the following problems.

  This is because when the shock absorber is operated suddenly and at high speed due to kickback input from shimmy or road surface, a large pressure due to the hydraulic oil that tries to pass through the first valve (second valve) The first valve body (second valve body) suddenly and greatly increases from the first valve seat (second valve seat) because the urging force of the urging means loses the above pressure. There is a possibility that the damping force will drop and the damping force will not be generated as intended.

  Therefore, the present invention was devised to improve the above-described problems, and the object of the present invention is to prevent the damping force from dropping even when the shock absorber operates rapidly and at high speed. It is to provide a damping valve.

  In order to achieve the above-described object, the problem-solving means of the present invention includes a hollow valve case having a port communicating with the inside and the outside in an intermediate side portion, and a first flow leading to the port with one end side of the valve case as an upstream side. A first flow path, a second flow path leading to the other end of the valve case with the port as an upstream side, an annular first valve seat formed in the middle of the first flow path, and a first valve seated on and off the first valve seat A first valve composed of a body, an annular second valve seat formed in the middle of the second flow path and coaxially disposed on the first valve seat, and a second valve body seated on and off the second valve seat A second valve; and a biasing means for biasing the second valve body toward the second valve seat and biasing the first valve body toward the first valve seat via the second valve body. A damping valve with a first fixed throttle upstream from the first valve in the first flow path and a second fixed throttle upstream from the second valve in the second flow path. The features.

  In the damping valve of the present invention, the fixed throttles are provided on the upstream side of the first valve and the second valve, respectively, so that the shock absorber to which the damping valve is applied may be operated suddenly and at high speed by an external force. This prevents sudden and large pressure from acting on the first valve and the second valve, preventing the first valve body and the second valve body from excessively retracting from the corresponding first valve seat and second valve seat respectively. It is possible to prevent the damping force from dropping.

  Therefore, according to the damping valve of the present invention, even when the shock absorber to which the damping valve is applied operates suddenly and at high speed due to an external force, it is possible to prevent a drop in the damping force generated by the shock absorber. is there.

  The present invention will be described below based on the illustrated embodiment. FIG. 1 is a longitudinal sectional view showing a damping valve according to an embodiment.

  As shown in FIG. 1, the basic structure of the damping valve V according to the embodiment is a hollow valve case 1 having a port 1a communicating with the inside and outside at the intermediate side portion, and one end 1b side of the valve case 1 on the upstream side. A first flow path P1 that communicates with the port 1a, a second flow path P2 that communicates with the port 1a as the upstream side and the other end 1c side of the valve case 1, and an annular first formed in the middle of the first flow path P1 A first valve 2 composed of a valve seat 3 and a first valve body 4 that is attached to and detached from the first valve seat 3, and an annular formed coaxially with the first valve 3 seat that is formed in the middle of the second flow path P2. A second valve 5 composed of a second valve seat 6 and a second valve body 7 that is attached to and detached from the second valve seat 6; and the second valve body 7 is urged toward the second valve seat 6 and the second valve An urging means for urging the first valve body 4 toward the first valve seat 3 via the body 7, and a first provided upstream of the first valve 2 of the first flow path P1. A constant diaphragm 9 is configured by a second fixed throttle 10 from the second valve 5 of the second passage P2 to the upstream side.

  As shown in FIG. 1, the damping valve V includes a cylinder 11, a piston 12 that divides the inside of the cylinder 11 into two pressure chambers R1, R2, and an accumulator A. This is applied to the damper D.

 In detail, in this steering damper D, a piston rod 13 is connected to the piston 12, and the piston rod 13 passes through the axial center portions of both ends of the cylinder 11, and the steering damper D is It is configured as a so-called double rod type damper.

  Further, the damping valve V is incorporated in the flow passages 14, 15, and 16 that connect the one pressure chamber R1 and the other pressure chamber R2 of the steering damper D configured as described above. In this case, with respect to the movement of the piston 12 in the left direction in FIG. 1 with respect to the cylinder 11, the first valve 2 opens and applies resistance to the hydraulic fluid passing therethrough to generate a damping force. With respect to the movement of the piston 12 in the right direction, the second valve 5 is opened to give resistance to the working oil passing therethrough and generate a damping force.

  Hereinafter, the damping valve V will be described in detail. The valve case 1 has a cylindrical shape, and is provided on the inner side on the other end 1c side from the port 1a and the port 1a that is provided on the intermediate side and communicates inside and outside. A second flange 1d, the outer periphery on the other end 1c side from the port 1a is larger in diameter than the one end 1b side, and the inner periphery on the one end 1b side is larger in diameter to form a large diameter portion 1e. It is accommodated in a valve hole 17 provided in H. The outer periphery of the valve case 1 on the one end 1b side is screwed to the valve hole 17 to prevent the valve case 1 from falling off the valve hole 17.

  Then, the first flow path P1 is formed in a route communicating with the port 1a through the inside of the valve case 1 from the opening of the one end 1b with the one end 1b side of the valve case 1 being upstream, and with the port 1a as the upstream from the port 1a. A second flow path P2 is formed by a route that communicates with the opening of the other end 1c of the valve case 1 through the inside of the valve case 1.

  On the other hand, the valve hole 17 of the valve housing H is composed of a distal end portion 17a having a small diameter, an intermediate portion 17b having a larger diameter than the distal end portion 17a, and a proximal end portion 17c having a larger diameter than the intermediate portion 17b. When fixed in the hole 17, the port 1a is opposed to the intermediate portion 17b while being isolated from the distal end portion 17a and the proximal end portion 17c, and the valve case 1 is placed in the distal end portion 17a and the intermediate portion 17b. It is to be accommodated. The valve housing H may be integrated with the cylinder 11 of the steering damper D or may be a separate body.

  The bottom of the valve hole 17 at the distal end portion 17 a communicates with one pressure chamber R 1 of the steering damper D through the flow path 14, and the base end portion 17 c of the valve hole 17 passes through the flow path 15 with respect to the steering damper D. The intermediate portion 17 b is communicated with the other pressure chamber R 2 of the steering damper D through the flow path 16. The flow path 15 is provided with a check valve 18 that allows only the flow of hydraulic oil from the damping valve V toward the one pressure chamber R1, and the flow path 15 is a one-way flow path. .

  Therefore, the first flow path P1 described above communicates one pressure chamber R1 and the other pressure chamber R2 through the flow path 14 and the flow path 16, and the other second flow path P2 is a flow path. One pressure chamber R1 and the other pressure chamber R2 are communicated with each other through 15 and the flow path 16. A seal ring 24 that prevents direct communication between the flow path 14 and the flow path 16 is provided on the outer periphery of the valve case 1 so that the flow path 14 and the flow path 16 do not communicate with each other without passing through the first flow path P1. Is provided, and the flow path 15 and the flow path 16 are prevented from communicating with each other without passing through the second flow path P2, and direct communication between the flow path 15 and the flow path 16 is prevented on the outer periphery of the valve case 1. A seal ring 25 is provided.

  Further, the base end portion 17c of the valve hole 17 communicates with the accumulator A, and the accumulator A compensates for the volume change of the hydraulic oil in the hydraulic circuit of the steering damper D including the pressure chambers R1 and R2 due to the temperature change. It is supposed to be.

  Returning, the first valve seat member 19 is slidably inserted into the inner diameter large diameter portion 1e on the one end 1b side of the valve case 1, and the first valve seat member 19 has a large diameter portion. 1e, and a first flange 19b that is provided at the left end in FIG. 1 and protrudes inward. And this 1st valve-seat member 19 forms the cyclic | annular 1st valve-seat 3 with which the 1st valve body 4 is separated from the inner peripheral part of the left end surface in FIG. 1 of the 1st flange 19b.

  And the cap 20 arrange | positioned outward from the 1st valve-seat member 19 is fitted by the opening end of the large diameter part 1e of the inner periphery by the side of the one end 1b of this valve case 1, The cap 20 is a valve | bulb. It is clamped and fixed between the case 1 and the bottom of the tip 17a of the valve hole 17.

  The cap 20 includes a fitting portion 20a fitted to the large diameter portion 1e of the valve case 1, a rod 20b rising from the center of the fitting portion 20a, and a through hole 20c penetrating the fitting portion 20a. The cap 20 does not block the first flow path P1. The rod 20b has a diameter smaller than the inner diameter of the first flange 19b of the first valve seat member 19 and penetrates to an intermediate portion of the first flange 19b. The rod 20b and the inner peripheral surface of the first flange 19b Thus, a first fixed throttle 9 having a predetermined annular gap is formed upstream of the first valve 2.

  A spring 21 is interposed between the bottom of the first valve seat member 19 and the fitting portion 20a of the cap 20, and the first valve seat member 19 is attached to the inside of the valve case 1. It is energized. The first valve seat member 19 is restricted from further movement inward of the valve case 1 by a stepped portion at the end of the large diameter portion 1e of the valve case 1.

  Further, the first valve body 4 is slidably accommodated in the valve case 1 between the second flange 1d and the first valve seat member 19. The first valve body 4 is provided on the first valve seat 3 side of the body portion 4a having a plurality of sliding contact portions 4b that are in sliding contact with the inner periphery of the valve case 1, and on the first valve seat 3 side. An annular seat portion 4c that contacts the head portion, a head portion 4d that protrudes from the inner peripheral side of the seat portion 4c and can enter the first flange 19b of the first valve seat member 19, and a second flange 1d side of the body portion 4a And an abutting shaft 4e protruding into the second flange 1d. The axial length of the head portion 4d entering the first flange 19b is considered so as not to interfere with the rod 20b of the cap 20 even when the seat portion 4c is seated on the first valve seat 3. ing.

  The body portion 4a of the first valve body 4 has only the sliding contact portion 4b formed along the axial direction with respect to the body portion 4a in sliding contact with the inner periphery of the valve case 1, and the sliding contact portion of the body portion 4a. 4b and the inner periphery of the valve case 1 are formed with a gap that allows the hydraulic oil to pass therethrough so that the first flow path P1 is not blocked, and the first valve body 4 is The port 1a is not blocked even if the body 4a is moved backward from the valve seat 3 and faces the port 1a.

  In the first valve body 4, the seat portion 4 c is seated on the first valve seat 3 to close the first flow path P <b> 1, and the seat portion 4 c is separated from the first valve seat 3. By retracting the first valve body 4 from the first valve seat 3 to the left in FIG. 1, the first flow path P1 can be opened, and the first valve 2 and the first valve seat 3 can be used to open the first valve 2. Is configured.

  In the first valve 2, when the piston 12 in the steering damper D moves to the right and the hydraulic fluid moves from the other pressure chamber R2 to the one pressure chamber R1, the other which becomes high pressure 1 acts on the left end of the first valve body 4 in FIG. 1 via the flow path 16 so that it is seated on the first valve seat 3 and the first flow path P1 is maintained closed. When the piston 12 in the steering damper D moves to the left and hydraulic fluid moves from one pressure chamber R1 to the other pressure chamber R2, the pressure in the one pressure chamber R1 that is high pressure flows through the flow path 14. 1 acts on the right end of the first valve body 4 in FIG. 1, and is separated from the first valve seat 3 to open the first flow path P <b> 1. In the first valve 2, when the first flow path P <b> 1 is opened, a resistance corresponding to the degree of opening of the first valve 2 is given to the flow of hydraulic oil passing through the first valve 2.

  In the case of this embodiment, in the state in which the head portion 4d is present in the first flange 19b, the flow passage area in the first valve 2 is an annular gap formed by the head portion 4d and the inner edge of the first valve seat 3. The change ratio of the flow passage area with respect to the retraction amount of the first valve body 4 from the first valve seat 3 can be arbitrarily adjusted by the setting of the head portion 4d. If not necessary, the head portion 4d may be omitted, and the sheet portion 4c has a planar shape, but may have a tapered surface shape.

  Subsequently, the second valve seat 6 disposed coaxially with the first valve seat 3 is formed on the left end surface in FIG. 1 on the inner peripheral side of the second flange 1d provided on the inner periphery of the valve case 1, A second valve body 7 is attached to and detached from the second valve seat 6.

  The second valve body 7 is accommodated in the valve case 1 so as to be slidable from the second flange 1d forming the second valve seat 6 to the other end 1c side, and the urging force to which the valve housing H is fixed. It is connected to the movable iron core 23 of the solenoid 22 as means.

  The second valve body 7 is provided on the second valve seat 6 side of the trunk portion 7a having a plurality of sliding contact portions 7b that are in sliding contact with the inner periphery of the valve case 1, and the second valve seat 7a. 6 is provided with an annular sheet portion 7c that abuts 6 and a head portion 7d that protrudes from the inner peripheral side of the sheet portion 7c and can enter the second flange 1d.

  The right end in FIG. 1 of the head portion 7d that enters the second flange 1d has the second valve body 7 seated on the second valve seat 6 and the first valve body 4 seated on the first valve seat 3. In this state, it is possible to contact the abutting shaft 4e of the first valve body 4, and when the urging force is applied to the second valve seat 6 side by the solenoid 22, The body 7 is brought into contact with the abutting shaft 4 e and the first valve body 4 can be urged toward the first valve seat 3 via the second valve body 7.

  Thus, the abutting shaft 4e plays a role of transmitting the urging force of the solenoid 22 to the first valve body 4, but the abutting shaft 4e projects into the second flange 1d, It also plays a role of forming a second fixed throttle 10 having a predetermined annular gap upstream from the second valve 5 with the inner periphery of the second flange 1d.

  Returning to the description of the second valve body 7, the body portion 7 a of the second valve body 7 slidably contacts only the sliding contact portion 7 b formed along the axial direction with respect to the body portion 7 a on the inner periphery of the valve case 1. A gap is formed between the sliding contact portion 7b of the body portion 7a and the inner periphery of the valve case 1 so as to allow the hydraulic oil to pass therethrough so that the second flow path P2 is not blocked. It has become.

  In the second valve body 7, the seat portion 7c is seated on the second valve seat 6 to close the second flow path P2, and the seat portion 7c is separated from the second valve seat 6. By retracting the second valve body 7 from the second valve seat 6 to the left in FIG. 1, the second flow path P2 can be opened, and the second valve body 7 and the second valve seat 6 The valve 5 is configured.

  In the second valve 5, when the piston 12 in the steering damper D moves to the right and hydraulic oil moves from the other pressure chamber R 2 to the one pressure chamber R 1, Since the pressure in the pressure chamber R2 acts on the right side of the second valve element 7 in FIG. 1 through the flow path 16, it is separated from the second valve seat 6 to open the second flow path P2. Further, in the second valve 5, similarly to the first valve 2, when the second flow path P <b> 2 is opened, the resistance corresponding to the degree of opening of the second valve 5 with respect to the flow of hydraulic oil passing through the second valve 5. Is supposed to give.

  In the case of this embodiment, similarly to the first valve 2, when the head portion 7d exists in the second flange 1d, an annular gap formed between the head portion 7d and the inner edge of the second valve seat 6 is used. The flow passage area in the second valve 5 is determined, and the change ratio of the flow passage area with respect to the retraction amount of the second valve body 7 from the second valve seat 6 can be arbitrarily adjusted by setting the head portion 7d. The head portion 7d may be omitted if it is not necessary, and the shape of the sheet portion 7c is flat, but may be tapered.

  Subsequently, the solenoid 22 as the urging means only needs to be able to urge the second valve body 7 toward the second valve seat 6 with the generated urging force, so that the push type or the pull type may be used. In either case, the first valve body 4 and the second valve body 7 are directed toward the first valve seat 3 and the second valve seat 6, respectively, depending on the magnitude of the current supplied to the solenoid 22. It is possible to adjust the power to be energized.

  In the damping valve V, a biasing force in the right direction in FIG. 1 is generated in the solenoid 22 to bias the second valve body 7 toward the second valve seat 6 and the first valve body 4 is seated. The first valve body 4 is separated from the first valve seat 3 by adjusting the biasing force of the solenoid 22 and the first valve body 3 is urged and seated toward the first valve seat 3. The amount of retraction of the body 4 from the first valve seat 3, the cracking pressure at which the second valve body 7 moves away from the second valve seat 6, and the amount of retraction of the second valve body 7 from the second valve seat 6 are adjusted. Can be done.

  That is, since the urging force acting on the first valve body 4 and the second valve body 7 is generated by the urging force of the single solenoid 22, the cracking pressure and the valve opening amount in the first valve 2 and the second valve 5 are equal. In addition, the damping force generated in both the first valve 2 and the second valve 5 can be adjusted by adjusting the urging force of the solenoid 22.

  In the case of this embodiment, the first valve seat 3 is provided on the first valve seat member 19 which is slidable in the valve case 1 in the axial direction. Therefore, even if there is a dimensional tolerance in the axial length of each member in the damping valve V, the first valve body 4 is moved by the urging force applied from the solenoid 22. Although it is possible to securely seat the first valve seat 3, the first valve seat 3 may be provided directly on the valve case 1.

  Subsequently, the operation of the damping valve V in the present embodiment will be described. First, when the piston 12 of the steering damper D moves to the left in FIG. 1 with respect to the cylinder 11, the volume of one pressure chamber R1 becomes smaller and the volume of the other pressure chamber R2 becomes larger. The hydraulic oil in the chamber R1 passes through the flow path 14 and is guided to the first flow path P1.

  Then, the hydraulic oil guided to the first flow path P1 presses the first valve body 3 and the first valve seat member 19 to the left in FIG. 1, and the first valve seat member 19 is formed on the large-diameter portion 1e of the valve case 1. A solenoid in which a force that presses the first valve body 3 to the left in FIG. 1 acts on the first valve body 3 via the second valve body 7 after the movement is restricted by contacting the terminal step. When the urging force 22 is overcome, the first valve body 4 is separated from the first valve seat 3 and the first valve 2 is opened as shown in FIG.

  Then, the hydraulic oil passes through the first valve 2 and moves into the other pressure chamber R <b> 2 via the flow path 16. Therefore, in the steering damper D, when the piston 12 moves to the left, the first valve 2 generates a damping force.

  Here, prior to the opening operation of the first valve 2, the hydraulic oil guided from the one pressure chamber R1 to the first flow path P1 is formed by the rod 20b and the inner periphery of the first flange 19b. Since it passes through the fixed throttle 9, even if the piston 12 is operated suddenly and at high speed by an external force, a sudden and large pressure does not act on the first valve body 4, and the first valve body 4 A situation in which the first valve seat 3 retreats excessively can be prevented, and a drop in damping force can be prevented.

  In addition, when the 1st valve body 4 reverse | retreats as mentioned above, the 2nd valve body 7 is also pressed via the abutting shaft 4e, and the 2nd valve 5 also opens, but the 2nd flow path P2 Even if the pressure chamber R1 is opened, the pressure in one pressure chamber R1 is greater than the pressure in the second flow path P2 communicated with the other pressure chamber R2 via the flow path 16, and the check valve 18 passes through the flow path 15. Since it remains shut off, the second valve 5 does not affect the damping force generated by the steering damper D.

  On the other hand, when the piston 12 of the steering damper D moves to the right in FIG. 1 with respect to the cylinder 11, the volume of the other pressure chamber R2 decreases and the volume of one pressure chamber R1 increases. The hydraulic oil in the pressure chamber R2 passes through the flow path 16 and is guided to the second flow path P1. In this case, the first valve body 4 is pressed against the first valve seat 3 by the pressure of the other pressure chamber R2 introduced into the valve case 1 from the flow path 16 side, thereby closing the first flow path P1. Therefore, the movement of the hydraulic oil from the other pressure chamber R2 to the one pressure chamber R1 via the first flow path P1 is prevented.

  The hydraulic fluid guided to the second flow path P2 presses the second valve body 7 to the left side in FIG. 1, and the pressing force is against the urging force of the solenoid 22 acting on the second valve body 7. When overcome, the second valve body 7 is separated from the second valve seat 6 and the second valve 5 is opened as shown in FIG.

  Then, the hydraulic oil passes through the second valve 5 and moves into one pressure chamber R <b> 1 through the flow path 15. Therefore, in this steering damper D, when the piston 12 moves to the right, the second valve 5 generates a damping force.

  Here, prior to the opening operation of the second valve 5, the hydraulic fluid introduced from the other pressure chamber R2 to the second flow path P <b> 2 flows between the abutting shaft 4 e of the first valve body 4 and the second flange 1 d. Since it passes through the second fixed throttle 10 formed by the inner periphery, sudden and large pressure acts on the second valve body 7 even if the piston 12 is suddenly and rapidly operated by an external force. Without such a situation, it is possible to prevent the second valve body 7 from excessively retreating from the second valve seat 6 and to prevent the damping force from dropping.

  Therefore, according to the damping valve V, it is possible to prevent the damping force generated by the steering damper D from dropping even when the piston 12 operates rapidly and at high speed with respect to the cylinder 11.

  Further, the first fixed throttle 9 is constituted by a gap between the rod 20b and the inner circumference of the first flange 19b, and the second fixed throttle 10 is constituted by a gap between the abutting shaft 4e and the inner circumference of the second flange 1d. Therefore, the shape of the fixed throttle can be made the same, the damping characteristic can be made equal on both sides of the steering damper D, and the fixed throttle must be provided on the valve case 1 and the first valve seat member 19 botheringly. Since there is no, manufacturing cost is not deteriorated.

  Further, when the second fixed throttle 10 is provided, an abutting shaft 4e necessary for applying a biasing force of the solenoid 22 to the first valve body 4 via the second valve body 7 is used. Therefore, there is no increase in the number of parts for the installation of the second fixed aperture 10, and the manufacturing cost is not deteriorated in this respect as well.

  Note that the first fixed throttle 9 is provided with a round channel shape that does not match the channel shape of the second fixed throttle 10, but the inner circumference of the first flange 19b regardless of the rod 20b. The diameter of the portion that does not interfere with the first valve body 4 may be set to a small diameter to form a fixed throttle.

  Further, when the second fixed throttle 10 is set to have a separate configuration, for example, a diameter such that the abutting shaft 4e is in sliding contact with the inner periphery of the second flange 1d of the valve case 1, the outer periphery of the abutting shaft 4e A notch may be provided to form a fixed aperture with the notch. The same applies to the rod 20b in the first fixed throttle 9.

  Furthermore, in this embodiment, the damping force generation source in the steering damper D is only the first valve 2 and the second valve 5. For example, the piston 12 bypasses the flow paths 14, 15, and 16. A passage that provides resistance to the flow of hydraulic fluid that passes through one pressure chamber R1 and the other pressure chamber R2 is provided, and only the first valve 2 and the second valve 5 are used when the damping force of the steering damper D is generated. Of course, the damping force may be generated by the separate passage.

  Furthermore, since the damping valve V is suitable for generating equal damping force when the shock absorber is operated on both the left and right sides, it is optimal for the steering damper D that is required to generate equal damping force on both the left and right sides. However, it is of course possible to be applied to a shock absorber for other uses, such as the seat portion 4c of the first valve body 4, the head portion 4d and the seat portion 7c of the second valve body 7, It is also possible to make the damping characteristics realized by the first valve 2 and the second valve 5 different by making the shapes of the head portions 7d different from each other.

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

It is a longitudinal cross-sectional view which shows the state which applied the damping valve in one Embodiment to a steering damper. It is a longitudinal cross-sectional view which shows the state which the 1st valve in the damping valve of one Embodiment opened. It is a longitudinal cross-sectional view which shows the state which the 2nd valve in the damping valve of one Embodiment opened.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve case 1a Port 1b One end 1c of a valve case 1d The other end 1d of a valve case 2nd flange 1e Large diameter part 2 in a valve case 1st valve 3 1st valve seat 4 2nd valve body 4a The trunk | drum 4b in 1st valve body Sliding contact portion 4c in the first valve body Seat portion 4d in the first valve body Head portion 4e in the first valve body Abutting shaft 5 Second valve 6 Second valve seat 7 Second valve body 7a Body portion in the second valve body 7b Sliding contact portion 7c in the second valve body 7c Seat portion in the second valve body Head portion 9 in the second valve body 1st fixed throttle 10 Second fixed throttle 11 Cylinder 12 Piston 13 Piston rods 14, 15, 16 Flow path 17 Valve hole 17a Tip portion 17b in valve hole Intermediate portion 17c in valve hole Base end portion 18 in valve hole Check valve 19 First valve seat member 19a Tube portion 19b in first valve seat member First flange 20 Cap 20a Fitting portion 20b in cap Rod 20c Cap through hole 21 Spring 22 Solenoid 23 as biasing means Movable iron core 24, 25 in solenoid Seal ring A Accumulator D Steering damper H Valve housing P1 First flow path P2 Second flow path R1 One pressure chamber R2 The other pressure chamber V Damping valve

Claims (2)

A hollow valve case having a port communicating with the inside and outside at the intermediate side, a first flow path leading to the port with one end side of the valve case as an upstream side, and communicating with the other end side of the valve case with the port as an upstream side Formed in the middle of the second flow path, a first valve composed of an annular first valve seat formed in the middle of the first flow path, and a first valve body seated on and off the first valve seat A second valve comprising an annular second valve seat arranged coaxially with the first valve seat and a second valve body seated on and off from the second valve seat, and the second valve body facing the second valve seat And a biasing means for biasing the first valve body toward the first valve seat via the second valve body, wherein the first valve is disposed upstream of the first valve in the first flow path. A damping valve, characterized in that a fixed throttle is provided and a second fixed throttle is provided upstream of the second valve of the second flow path. The first fixed throttle is formed by a gap between the inner periphery of the first flange forming the first valve seat and the rod arranged on the inner peripheral side of the first flange, and the second fixed throttle is It is arranged on the inner periphery of the second flange that forms the second valve seat and on the inner periphery of the second flange, and extends from the first valve body toward the second valve body so as to contact the second valve body. The damping valve according to claim 1, wherein the damping valve is formed with a gap between the abutting shaft.

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