Attenuation force regulating valve

Abstract

To provide technique enabling generation and regulation of attenuation force by simple constitution.SOLUTION: An attenuation force regulating valve is provided, having: a pressure control valve element which opens and closes a flow passage by being seated on and separated from a valve seat; a pilot valve element which opens and closes a portion more downstream than a portion of the flow passage which is opened and closed by the pressure control valve element; an actuator which can drive the pilot valve element toward a valve-closing direction; a guide member which guides the axial movement of the pressure control valve element, and has a flow passage progressing toward the pilot valve element and has a pilot valve seat; an elastic member energizing the pressure control valve element toward the valve seat; and a centering portion which is provided integrally with the guide member, and centers an internal periphery of the elastic member, and has an axial movement regulation portion regulating the axial movement of the elastic member.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a damping force control valve. [Background technology]

[0002] For example, the damping force generating mechanism described in Patent Document 1 includes a flow path forming section that forms a flow path through which liquid flows, a valve that controls the flow of the liquid in the flow path, a back pressure control valve that controls the pressure in a back pressure chamber into which the liquid flows to apply back pressure to the valve, and a accommodating section that is formed in a cylindrical shape with one opening end narrower than the other opening end, forms the back pressure chamber, and accommodates at least the valve and the back pressure control valve. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2019 / 239718 Summary of the Invention [Problem to be solved by the invention]

[0004] In the damping force generating mechanism described in Patent Document 1, the member that houses the valve so that it can be opened and closed and the valve seat of the back pressure control valve are configured as separate parts, and there is room for improvement from the perspective of simplification. An object of the present invention is to provide a damping force adjustment valve or the like that is capable of generating and adjusting a damping force with a simple configuration. [Means for solving the problem]

[0005] The present invention, which was completed with respect to this object, is a damping force control valve comprising: a pressure control valve element which opens and closes a flow path by seating and lifting off a valve seat; a pilot valve element which opens and closes a portion of the flow path downstream of a portion opened and closed by the pressure control valve element; an actuator which can drive the pilot valve element in a valve closing direction; a guide member which guides the axial movement of the pressure control valve element and has a flow path toward the pilot valve element and a pilot valve seat; an elastic member which urges the pressure control valve element toward the valve seat; and a centering portion which is provided integrally with the guide member, which centers the inner periphery of the elastic member and has an axial movement restricting portion which restricts the axial movement of the elastic member. Effect of the Invention

[0006] According to the present invention, it is possible to generate and adjust a damping force with a simple configuration. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of a schematic configuration of a suspension device according to a first embodiment. [Diagram 2] 1 is a diagram showing an example of a cross section of a damping force generating device according to a first embodiment. [Diagram 3] 3 is a diagram showing an example of a perspective cross-sectional view of a part of a main valve portion and a damping force adjuster of the first embodiment. FIG. [Figure 4] 3 is a diagram showing an example of a partial cross section of a main valve portion and a damping force adjuster of the first embodiment. FIG. [Diagram 5] FIG. 4 is a diagram showing an example of a portion of a seal member. [Figure 6] 13A and 13B are diagrams illustrating an example of an oil flow when the moving speed of the piston portion is low in a state in which the pressing force of the pressing member is set to the smallest. [Figure 7] 13A and 13B are diagrams illustrating an example of an oil flow when the moving speed of a piston portion is high in a state in which the pressing force of a pressing member is set to a minimum. [Figure 8]13A and 13B are diagrams illustrating an example of an oil flow when the moving speed of the piston portion is low in a state in which the pressing force of the pressing member is maximized. [Figure 9] 13A and 13B are diagrams illustrating an example of an oil flow when the moving speed of a piston portion is high in a state in which the pressing force of a pressing member is maximized. [Figure 10] 11 is a diagram illustrating an example of an oil flow when a solenoid portion is in a non-energized state and a piston portion moves at a low speed. FIG. [Figure 11] 11A and 11B are diagrams illustrating an example of the flow of oil when a solenoid portion is in a non-energized state and a piston portion moves at a high speed. [Figure 12] 13 is a diagram showing an example of a schematic configuration of an elastic member according to a second embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First Embodiment FIG. 1 is a diagram showing an example of a schematic configuration of a suspension device 1 according to the first embodiment. The suspension system 1 is a suspension used in four-wheeled vehicles such as passenger automobiles, and as shown in Fig. 1, comprises a hydraulic shock absorber 2 and a coil spring 3 arranged on the outside of the shock absorber 2. The suspension system 1 also comprises a lower spring sheet 4 that supports an end of the coil spring 3 on one side in the axial direction (the lower side in Fig. 1) of a rod 20 described below, and an upper spring sheet 5 that supports an end of the coil spring 3 on the other side in the axial direction of the rod 20 (the upper side in Fig. 1).

[0009] The suspension device 1 also includes a vehicle body side bracket 6 for mounting the suspension device 1 to a vehicle, a wheel side bracket 7 for mounting the suspension device 1 to a wheel, and a dust cover 8 that covers at least a portion of the cylinder portion 10 and the rod 20. Hereinafter, the axial direction of the rod 20 may be simply referred to as the "axial direction." Also, one side in the axial direction (lower side in FIG. 1) and the other side in the axial direction (upper side in FIG. 1) may be simply referred to as the "one side" and the "other side," respectively. Also, a direction intersecting the axial direction (e.g., a perpendicular direction) may be referred to as the "radial direction." In the radial direction, the side of the center line of the cylinder 11 may be simply referred to as the "inner side," and the side away from the center line may be simply referred to as the "outer side."

[0010] The shock absorber 2 includes a cylinder portion 10 that contains oil, and a rod 20 that has one side that is slidably inserted into the cylinder portion 10 and the other side that is provided so as to protrude from the cylinder portion 10. The shock absorber 2 also includes a piston portion 30 that is provided at one end of the rod 20, and a bottom portion 40 that is provided at one end of the cylinder portion 10. The shock absorber 2 further includes a damping force generating device 50 that is provided outside the cylinder portion 10 and generates a damping force.

[0011] The cylinder section 10 has a cylinder 11 that contains oil, an outer cylinder body 12 provided on the outside of the cylinder 11, and a damper case 13 provided on the outside of the cylinder 11 and further outside the outer cylinder body 12. The cylinder section 10 also has a rod guide section 14 that movably supports the rod 20, a bump stopper cap 15, and an oil seal 16 that prevents foreign matter from entering the cylinder section 10.

[0012] The cylinder 11 is formed in a cylindrical shape, and a communication hole 11H that communicates between the inside and the outside is formed at the other end. The outer cylinder 12 is formed in a cylindrical shape. The outer cylinder 12 forms a communication path L between the outer cylinder 12 and the cylinder 11. The outer cylinder 12 has an outer cylinder opening 12H and an outer connection part 12J at a position facing the damping force generating device 50. The outer connection part 12J has an oil flow path, and protrudes outward to form a connection part with the damping force generating device 50.

[0013] The damper case 13 is formed in a cylindrical shape. The damper case 13 forms a reservoir chamber R between the damper case 13 and the outer cylinder body 12, in which oil is stored. The reservoir chamber R absorbs oil in the cylinder 11 and supplies oil to the cylinder 11 as the rod 20 moves relative to the cylinder 11. The reservoir chamber R also stores oil that flows out from the damping force generating device 50. The damper case 13 also has a case opening 13H at a position facing the damping force generating device 50.

[0014] The rod 20 is a rod-shaped member that extends long in the axial direction. One side of the rod 20 holds the piston portion 30. The other side of the rod 20 is connected to, for example, a vehicle body via a connecting member or the like (not shown).

[0015] The piston portion 30 includes a piston body 31 having a plurality of piston oil passage ports 311, a piston valve 32 that opens and closes the other side of the piston oil passage ports 311, and a spring 33 provided between the piston valve 32 and one end of the rod 20. The piston portion 30 divides the oil in the cylinder 11 into a first oil chamber Y1 and a second oil chamber Y2.

[0016] The bottom portion 40 has a valve seat 41, a check valve portion 43 provided on the other side of the valve seat 41, and a fixing member 44 provided in the axial direction. The bottom portion 40 separates the first oil chamber Y1 and the reservoir chamber R.

[0017] [Configuration and Function of Damping Force Generator 50] FIG. 2 is a diagram showing an example of a cross section of the damping force generating device 50 of the first embodiment. FIG. 3 is a diagram showing an example of a perspective cross section of a portion of the main valve portion 51 and the damping force adjuster 60 according to the first embodiment. FIG. 4 is a diagram showing an example of a partial cross section of a part of the main valve portion 51 and the damping force adjuster 60 according to the first embodiment. FIG. 5 is a diagram showing an example of a portion of the seal member 55. As shown in FIG.

[0018] In the following description, the longitudinal direction of the damping force generating device 50 shown in Fig. 2 (i.e., the intersecting direction (e.g., a direction substantially perpendicular to) the axial direction of the cylinder section 10 (see Fig. 1)) may be referred to as the "second axial direction". In addition, the central axis side of the cylinder section 10 in the second axial direction (the lower side of the damping force generating device 50 in Fig. 2) may be referred to as the "first side", and the side away from the central axis of the cylinder section 10 (the upper side of the damping force generating device 50 in Fig. 2) may be referred to as the "second side". 2 (i.e., a direction intersecting with the second axial direction) may be referred to as a "second radial direction". In the second radial direction, the side of the central axis along the second axial direction may be referred to as a "second inner side", and the side away from the central axis along the second axial direction may be referred to as a "second outer side".

[0019] 2, the damping force generating device 50 includes a main valve section 51 that mainly generates a damping force in the shock absorber 2 (see FIG. 1), and a damping force adjustment section 60 that adjusts the magnitude of the damping force generated by the damping force generating device 50. Furthermore, the damping force generating device 50 includes a connection flow path section 90 that forms a flow path for oil from the communication path L to the main valve section 51.

[0020] (Main valve part 51) The main valve section 51 has a main valve 52 that generates a damping force by controlling the flow of oil to throttle down, and a main valve seat 53 that faces the main valve 52 and comes into contact with it. The main valve section 51 also has an elastic member 54 that applies a force to press the main valve 52 against the main valve seat 53 by elastically deforming, and a seal member 55 that seals between the main valve 52 and a guide member 61, which will be described later.

[0021] ((Main Valve 52)) The main valve 52 has a cylindrical portion 521 and a bottom portion 522 that covers the opening of the cylindrical portion 521 on the first side. The inner diameter of the cylindrical portion 521 is larger than the inner diameter of the main valve seat 53, and the outer diameter is smaller than the diameter of the inner circumferential surface of a guide member 61, which will be described later. The end portion on the first side of the cylindrical portion 521 has an inner protruding portion 523 that is a portion protruding from the end face on the first side to the first side and is provided on the second inside, and an outer protruding portion 524 that is provided on the second outside of the inner protruding portion 523. The inner protruding portion 523 and the outer protruding portion 524 are each formed in a circular ring shape.

[0022] A groove 525 recessed from the outer circumferential surface to a second inward direction is formed around the entire circumference of the cylindrical portion 521. The cross section of the groove 525 cut along a plane passing through the center line of the cylindrical portion 521 is rectangular. A seal member 55 is fitted into the groove 525. The diameter of the outer circumferential surface of the cylindrical portion 521 is formed to decrease stepwise or steplessly as it moves away from the groove 525 in the second axial direction. Therefore, the gap between the cylindrical portion 521 and the inner circumferential surface of the guide member 61 is smallest on both sides of the groove 525, and increases stepwise or steplessly as it moves away from the groove 525 in the second axial direction.

[0023] In the bottom 522, an introduction hole 526 is formed around the center line of the cylindrical portion 521. In the example shown in Fig. 3, two introduction holes 526 are formed. Also, as shown in Fig. 3, a conical recess may be formed on each side of the introduction hole 526 in the second axial direction. When viewed in the second axial direction, the introduction hole 526 is formed so as not to overlap with a through hole 69 of the guide member 61, which will be described later.

[0024] ((Main valve seat 53)) The main valve seat 53 is a cylindrical member, and has a flange portion 531 at the end on the first side that protrudes cylindrically from the outer circumferential surface around the entire circumference toward the second outside. The flange portion 531 is a portion that protrudes in a cylindrical shape, and sandwiches the guide member 61 and the like between it and the cap portion 80, which will be described later.

[0025] The main valve seat 53 has an inner seat portion 533 at an end portion on the second side, which protrudes from the end face on the second side to the second side, and an outer seat portion 534 provided on the second outer side of the inner seat portion 533. The inner seat portion 533 and the outer seat portion 534 are each formed in an annular shape. The inner seat portion 533 is provided at a position corresponding to the inner protruding portion 523 of the main valve 52, and the outer seat portion 534 is provided at a position corresponding to the outer protruding portion 524 of the main valve 52.

[0026] ((Elastic member 54)) As shown in FIG. 3, the elastic member 54 is plate-shaped and has an annular portion 541 formed in an annular shape, and a plurality of arm portions 542 protruding from the annular portion 541 toward the second inside. The annular portion 541 is set to have approximately the same size as the end face of the second side of the cylindrical portion 521 of the main valve 52. The arm portion 542 is formed so that the circumferential size gradually decreases toward the second inner side. The diameter of an imaginary circle formed by connecting the tips of the multiple arm portions 542 is larger than the outer diameter of a first protrusion portion 662 (described later) of the guide member 61 and smaller than the outer diameter of the first surface 661.

[0027] The elastic member 54 is made of metal or the like, and the tips of the multiple arms 542 are supported by the first surface 661. The elastic member 54 elastically deforms so that the annular portion 541 moves toward the second side in response to movement of the main valve 52 toward the second side, and applies a force in a direction returning the main valve 52 toward the main valve seat 53. It is desirable that the multiple arms 542 are provided so that the elastic member 54 has a point-symmetric or line-symmetric shape when viewed in the second axial direction. For example, as shown in Fig. 3, an even number of arms 542 (e.g., six) are formed at equal intervals in the circumferential direction, so that the elastic member 54 has a point-symmetric or line-symmetric shape. The point-symmetric or line-symmetric shape of the elastic member 54 makes it easier to apply force to the main valve 52 evenly.

[0028] ((Sealing member 55)) The seal member 55 is an annular member whose cross-sectional shape when cut along a plane parallel to the second axial direction is a rectangle whose longitudinal direction is the second axial direction and whose short side direction is the second radial direction. However, the seal member 55 has a joint 550 formed in a part of its circumferential direction. The cross-sectional shape is not limited as long as the seal member 55 functions as such. FIG. 5 is a diagram showing a state in which the gap 550 is separated in order to clarify the configuration of the gap 550. The joint 550 has a rectangular parallelepiped protruding portion 551 at one circumferential end portion that protrudes toward the other end portion, and a receiving portion 552 is formed at the other end portion for seating the protruding portion 551. The seal member 55 is fitted into the groove 525 with the protruding portion 551 seated on the receiving portion 552.

[0029] The main valve 52 and main valve seat 53 configured as described above constitute a first valve mechanism V1 that opens and closes a first flow path R1 (see FIG. 7) through which oil flows from the communication path L to the reservoir chamber R through a horizontal hole 64 (described later) of the guide member 61. That is, the inner protrusion 523 and the outer protrusion 524 of the main valve 52 close the first flow path R1 by contacting an inner seat portion 533 and an outer seat portion 534 of the main valve seat 53, respectively, and open the first flow path R1 by moving away from the inner seat portion 533 and the outer seat portion 534. The first valve throttles the flow of oil in the first flow path R1 to generate a damping force.

[0030] (Damping force adjustment unit 60) 2, the damping force adjusting unit 60 has a guide member 61 that guides the movement of the main valve 52 in the second axial direction, and a control valve 70 that moves relative to the guide member 61 to open and close a second flow path R2 (see FIG. 6) that is formed in parallel with the first flow path R1. The damping force adjusting unit 60 also has a pressing member 77 that presses the control valve 70 against the guide member 61, a coil spring 79 that is disposed between the control valve 70 and the pressing member 77, and a solenoid 100 that moves the pressing member 77 toward and away from the guide member 61. The damping force adjusting unit 60 also has a restricting member 72 that restricts the movement of the control valve 70 toward the second side, and a biasing member 75 that applies a force to the control valve 70 in a direction opposite to the thrust of a solenoid unit 102 that will be described later. The damping force adjuster 60 also has a first spacer member 73A interposed between the biasing member 75 and the restricting member 72, a second spacer member 73B interposed between the restricting member 72 and a cap portion 80 (described later), and a third spacer member 73C interposed between the guide member 61 and the biasing member 75. The damping force adjuster 60 also has a cap portion 80 that covers the periphery of the control valve 70, the restricting member 72, the first spacer member 73A, the second spacer member 73B, and the third spacer member 73C.

[0031] ((Guide member 61)) The guide member 61 has a cylindrical portion 62 and a top portion 65 that covers an opening of the cylindrical portion 62 on the second side. The inner diameter of the cylindrical portion 62 is larger than the outer diameter of the cylindrical portion 521 of the main valve 52 and smaller than the outer diameter of the flange portion 531 of the main valve seat 53. The main valve 52 is disposed on the second inner side of the cylindrical portion 62. The outer diameter of the cylindrical portion 62 is smaller than the inner diameter of a first cylindrical portion 81 of the cap portion 80, which will be described later.

[0032] A step portion 63 is formed on the inner periphery of the end portion on the first side of the cylindrical portion 62, recessed from the end face on the first side to the second side, and the step portion 63 has a rectangular cross-sectional shape when cut along a plane passing through the center line of the cylindrical portion 62, and the flange portion 531 of the main valve seat 53 can be fitted into the step portion 63. A horizontal hole 64 in the second radial direction is formed in a portion of the cylindrical portion 62 on the second side of the stepped portion 63. The horizontal hole 64 is, for example, cylindrical, and a plurality of the horizontal holes 64 are formed in the circumferential direction. Incidentally, the horizontal hole 64 may be omitted by forming a gap when the step portion 63 and the flange portion 531 of the main valve seat 53 are fitted together and communicating it with a return hole 93 described later.

[0033] The top portion 65 has a central portion 66 which is an inner circumferential side (second inner side), an outer circumferential portion 67 which is an outer circumferential side (second outer side), and an intermediate portion 68 between the central portion 66 and the outer circumferential portion 67. The central portion 66 protrudes toward the main valve 52 side more than the outer circumferential portion 67, and the intermediate portion 68 is inclined flatly or curvedly with respect to the second radial direction.

[0034] A through hole 69 in the second axial direction is formed in the central portion 66. The through hole 69 is composed of a first hole 691 formed on the first side and a second hole 692 formed on the second side. The through hole 69 constitutes a part of the second flow path R2 branched off from the first flow path R1. The central portion 66 has a first protruding portion 662 that protrudes cylindrically from a first surface 661, which is an end surface of the first side, around the opening of the first hole 691 on the first side to the first side. The first surface 661 restricts movement of the elastic member 54 towards the second side. The first protruding portion 662 is inserted into the second inner side of the elastic member 54, and the outer circumferential surface of the first protruding portion 662 restricts movement of the elastic member 54 in the second radial direction.

[0035] Moreover, the central portion 66 has a second protruding portion 663 that protrudes from a second inner portion of the intermediate portion 68 in a conical shape toward the second side around the opening of the second hole 692 on the second side. The control valve 70 is contactable with and can be separated from the second protruding portion 663. Therefore, the control valve 70 closes the second flow path R2 when it comes into contact with the second protruding portion 663, and opens the second flow path R2 when the control valve 70 moves away from the second protruding portion 663. In other words, the control valve 70 and the second protruding portion 663 constitute a second valve mechanism V2 that opens and closes the second flow path R2.

[0036] Because the central portion 66 protrudes toward the main valve 52 side more than the outer circumferential portion 67 and the intermediate portion 68 is inclined with respect to the second radial direction, a recess 664 that is recessed toward the first side more than the end face on the second side of the outer circumferential portion 67 is formed around the second hole 692. The recess 664 allows the biasing member 75 to deform and can accommodate a portion of the first side of the control valve 70 even when the control valve 70 has moved furthest toward the first side and is in contact with the second protruding portion 663.

[0037] ((Control Valve 70)) The control valve 70 has a cylindrical portion 701 and a conical portion 702 that covers the opening on the first side of the cylindrical portion 701 and protrudes to the first side. The control valve 70 also has a protruding portion 703 that protrudes around the entire circumference to the second outside at the end of the cylindrical portion 701 on the first side. The control valve 70 also has a flat surface 704 that is perpendicular to the second axial direction at the end of the conical portion 702 on the second side and at a second inner position. The control valve 70 also has a protruding portion 706 that protrudes to the second outside at the center of the conical portion 702 in the second axial direction. The protruding portion 706 has a flat surface 707 that is perpendicular to the second axial direction.

[0038] The outer diameter of the cylindrical portion 701 is equal to or larger than the outer diameter of the flange portion 773 of the pressing member 77, and the inner diameter of the cylindrical portion 701 is smaller than the outer diameter of the flange portion 773. As a result, the end face on the second side of the cylindrical portion 701 comes into contact with the flange portion 773 of the pressing member 77.

[0039] Also, the size of the inner diameter of the cylindrical portion 701 is larger than the size of the outer diameter of the cylindrical portion 771 of the pressing member 77. As a result, the cylindrical portion 771 and the bottom portion 772 of the pressing member 77 are accommodated in the second inner side of the control valve 70 with the second end face of the cylindrical portion 701 in contact with the flange portion 773 of the pressing member 77. Then, the coil spring 79 is disposed inside the space 705 formed between the cylindrical portion 701 of the control valve 70 and the cylindrical portion 771 of the pressing member 77. The first end of the coil spring 79 is supported by the flat surface 704 of the control valve 70, and the second end of the coil spring 79 is supported by the flange portion 773 of the pressing member 77. In this way, the coil spring 79 is a member acting at both ends and does not have a fixed end, so that a part of the thrust of the solenoid portion 102 does not act on the fixed side member at the tip of the fixed end via the fixed end. Therefore, the thrust of the solenoid portion 102 applied to the coil spring 79 is entirely used to deform the coil spring 79 itself, resulting in high thrust efficiency.

[0040] ((Regulation member 72)) 3, the restricting member 72 has an annular portion 721 formed in an annular shape, and a plurality of arm portions 722 protruding toward a second inner side from the annular portion 721. The diameter of an imaginary circle formed by the second inner tips of the plurality of arm portions 722 is larger than the diameter of the outer circumferential surface of the cylindrical portion 701 of the control valve 70 and smaller than the diameter of the outer circumferential surface of the protruding portion 703.

[0041] ((First spacer member 73A, second spacer member 73B, and third spacer member 73C)) The first spacer member 73A, the second spacer member 73B, and the third spacer member 73C are annular members. The outer diameters of the first spacer member 73A, the second spacer member 73B, and the third spacer member 73C are larger than the inner diameter of a second cylindrical portion 82 of the cap portion 80, which will be described later, and smaller than the inner diameter of a first cylindrical portion 81, which will be described later. The inner diameters of the first spacer member 73A, the second spacer member 73B, and the third spacer member 73C are larger than the inner diameter of the second cylindrical portion 82 of the cap portion 80, and smaller than the inner diameter of the first cylindrical portion 81.

[0042] The first spacer member 73A and the second spacer member 73B are disposed between the first end face of the second cylindrical portion 82 of the cap portion 80 and the biasing member 75, and determine the position of the restricting member 72 in the second axial direction. More specifically, the restricting member 72 is located on the second side of the protruding portion 703 of the control valve 70, and restricts the control valve 70 from moving to the second side.

[0043] The position of the regulating member 72 in the second axis direction can be adjusted by adjusting the size (hereinafter, sometimes referred to as "thickness") of the first spacer member 73A and the second spacer member 73B in the second axis direction. For example, when it is desired to set the position of the regulating member 72 in the second axis direction to the first side from FIG. 4, it is preferable to make the thickness of the first spacer member 73A thinner than the thickness shown in FIG. 4 and the thickness of the second spacer member 73B thicker than the thickness shown in FIG. 4. On the other hand, when it is desired to set the position of the regulating member 72 in the second axis direction to the second side from FIG. 4, it is preferable to make the thickness of the first spacer member 73A thicker than the thickness shown in FIG. 4 and the thickness of the second spacer member 73B thinner than the thickness shown in FIG. 4.

[0044] The third spacer member 73C is disposed between the urging member 75 and the guide member 61 to determine the position of the urging member 75 in the second axial direction. The position of the urging member 75 in the second axial direction can be adjusted by adjusting the size of the third spacer member 73C in the second axial direction (hereinafter, sometimes referred to as "thickness"). For example, when it is desired to set the position of the urging member 75 in the second axial direction to the first side from FIG. 4, it is preferable to make the thickness of the third spacer member 73C thinner than the thickness shown in FIG. 4 and the thickness of the first spacer member 73A thicker than the thickness shown in FIG. 4. On the other hand, when it is desired to set the position of the urging member 75 in the second axial direction to the second side from FIG. 4, it is preferable to make the thickness of the third spacer member 73C thicker than the thickness shown in FIG. 4 and the thickness of the first spacer member 73A thinner than the thickness shown in FIG. 4.

[0045] ((biasing member 75)) The biasing member 75 is an annular leaf spring that applies a force to the control valve 70 in a direction against the thrust of the solenoid unit 102 and the spring force of the coil spring 79, and is set to a spring constant higher than that of the coil spring 79. The biasing member 75 has an annular portion 751 that is formed in an annular shape and functions as a fixed end, and a plurality of arm portions 752 that protrude from the annular portion 751 toward the second inner side and function as an acting end. The shape of the biasing member 75 is not limited to this, and the shape is not particularly limited as long as it has a fixed end and an acting end that acts on the control valve 70. For example, the plurality of arm portions 752 are provided in three at equal intervals in the circumferential direction of the annular portion 751. However, the number of the arm portions 752 is not limited to three, and may be two or less, or four or more. The shapes of the plurality of arm portions 752 may all be the same, or may be different from each other. For example, the circumferential sizes of the plurality of arm portions 752 may be different from each other. The biasing member 75 does not have to be a leaf spring, and may be an elastic member such as a coil spring interposed between the control valve 70 and the guide member 61.

[0046] ((Pressing member 77)) As shown in FIG. 4, the pressing member 77 has a cylindrical portion 771, a bottom portion 772 covering an opening on a first side of the cylindrical portion 771, and a flange portion 773 provided at an end portion on a second side of the cylindrical portion 771 and protruding toward the second outside around the entire circumference.

[0047] ((Coil spring 79)) Coil spring 79 is a compression coil spring that contacts control valve 70 on a first side and contacts pressing member 77 on a second side. Coil spring 79 applies forces to pressing member 77 and control valve 70 in directions that move pressing member 77 and control valve 70 away from each other. Note that instead of coil spring 79, another member, such as an elastic ring, may be used as long as it exhibits a similar function.

[0048] ((Cap part 80)) The cap portion 80 has three cylindrical portions having the same outer diameter but different inner diameters, namely, a first cylindrical portion 81 arranged on a first side, a second cylindrical portion 82 arranged on a second side from the first cylindrical portion 81, and a third cylindrical portion 83 arranged on the second side from the second cylindrical portion 82. The outer diameter of the cap portion 80 is smaller than the inner diameter of an inner housing 180 described later, and the cap portion 80 is arranged on the second inner side of the inner housing 180.

[0049] The inner diameter of the first cylindrical portion 81 is larger than the outer diameters of the guide member 61, the first spacer member 73A, the second spacer member 73B, the third spacer member 73C, the restricting member 72 and the biasing member 75, and is disposed on the second outer side of these members.

[0050] The inner diameter of the second cylindrical portion 82 is smaller than the outer diameters of the guide member 61, the first spacer member 73A, the second spacer member 73B, the third spacer member 73C, the restricting member 72, and the urging member 75. The guide member 61, the first spacer member 73A, the second spacer member 73B, the third spacer member 73C, the restricting member 72, and the urging member 75 are sandwiched between the first end face of the second cylindrical portion 82 and the flange portion 531 of the main valve seat 53, and the positions of these members in the second axial direction are fixed.

[0051] The inner diameter of the third cylindrical portion 83 is larger than the outer diameter of the plunger 117 described below and smaller than the outer diameter of a flange portion 773 of the pressing member 77. As a result, the first side end of the plunger 117, the pressing member 77, the coil spring 79, and the control valve 70 are accommodated inside the second inner side of the cap portion 80. The first side end of the third cylindrical portion 83 is formed with a groove portion 831 recessed from the end face toward the second side.

[0052] A second axial groove 84, which is a groove recessed from the outer peripheral surface to the second inner side, is formed over the entire area in the second axial direction on the outer periphery of the cap portion 80. One or more second axial grooves 84 are formed in the circumferential direction. In addition, a second radial groove 85, which is a groove recessed from the end face to the first side, is formed over the entire area in the second radial direction on the end portion of the second side of the cap portion 80. The second radial groove 85 is formed at a position corresponding to the second axial groove 84, and discharges oil that has passed through the inside of the second inner side of the third cylindrical portion 83 to an annular gap S1 described later.

[0053] (Solenoid 100) The solenoid 100 includes a valve portion 101 that opens and closes the second flow path R2, a solenoid portion 102 that drives a plunger 117 (described later) of the valve portion 101, and a housing 160 that accommodates the valve portion 101, a coil 121 (described later) of the solenoid portion 102, etc. The solenoid 100 also includes an elastic seal member 190 that seals a gap between the solenoid portion 102 and the housing 160.

[0054] ((Valve portion 101)) The valve portion 101 has a fixed portion 110 that is fixed, and a movable portion 116 that is movable relative to the fixed portion 110 . The fixed portion 110 has a first fixed member 111 provided on the first side, a second fixed member 112 provided on the second side of the first fixed member 111, and a spacer 113 provided between the first fixed member 111 and the second fixed member 112. The first fixed member 111 and the second fixed member 112 are molded using a magnetic material such as iron, and the spacer 113 is molded using a non-magnetic material such as resin.

[0055] The first fixed member 111 has a first protruding portion 111a that protrudes in a circular shape from the outer circumferential surface at the end portion on the first side to the second outside. Inside the first fixed member 111, a first bearing 114 is provided that supports a plunger 117 (described later) so as to be movable in the second axial direction. The first bearing 114 is cylindrical and fixed to the first fixed member 111 so as not to be movable.

[0056] The second fixing member 112 has a cylindrical portion 112a provided on the first side, and a cover portion 112b provided on the second side of the cylindrical portion 112a and covering the opening of the cylindrical portion 112a. An inner portion of cover portion 112b has second bearing 115 that supports plunger 117 (described later) so as to be movable in the second axial direction. Second bearing 115 is cylindrical, and is fixed to second fixed member 112 so as not to be movable.

[0057] The movable portion 116 has a cylindrical plunger 117 that holds the pressing member 77 , and a movable iron core 118 that is held around the plunger 117 . The plunger 117 is a rod-shaped member formed along the second axial direction. The plunger 117 holds the pressing member 77 on the first side, and holds a movable iron core 118 in the center in the axial direction. The plunger 117 is supported by the first bearing 114 and the second bearing 115 so as to be movable in the second axial direction. When the solenoid unit 102 is in an energized state, the plunger 117 is pushed out toward the first side together with the pressing member 77 by the solenoid unit 102. On the other hand, when the solenoid unit 102 is in a non-energized state, the plunger 117 is pushed back toward the second side together with the pressing member 77 by the coil spring 79.

[0058] ((Housing 160)) The housing 160 includes an outer housing 170 having a substantially cylindrical shape provided on the outside, and an inner housing 180 provided inside the outer housing 170. The outer housing 170 and the inner housing 180 can be, for example, molded from a metal. Alternatively, the outer housing 170 can be, for example, molded from a metal, and the inner housing 180 can be, for example, molded from a resin.

[0059] The outer housing 170 has a first cylindrical portion 171 provided on the first side, and a second cylindrical portion 172 provided on the second side of the first cylindrical portion 171. The inner diameter of the first cylindrical portion 171 and the inner diameter of the second cylindrical portion 172 are the same. On the other hand, the outer diameter of the first cylindrical portion 171 is larger than the outer diameter of the second cylindrical portion 172. The end portion on the second side of the first cylindrical portion 171 has an inclined surface 173 inclined with respect to the axial direction so that the diameter gradually increases from the second side to the first side.

[0060] The first cylindrical portion 171 has a protruding portion 174 at the end portion on the first side, which protrudes in an annular shape from the inner circumferential surface toward the second inner side. A groove 175 is formed in the first cylindrical portion 171, recessed from the outer circumferential surface 170a to the second inner side all around. The groove 175 has a first surface 176 which is a surface inclined in the second axial direction, a second surface 177 which is a surface forming an obtuse angle with the first surface 176, and a curved surface 178 formed between the first surface 176 and the second surface 177. The first surface 176 is formed on the first side relative to the second surface 177. In other words, the first surface 176 is located closer to the outside air than the second surface 177.

[0061] A recess 172a recessed inwardly from the outer circumferential surface is formed in the second cylindrical portion 172. The recess 172a has a rectangular parallelepiped shape and is formed in a portion of the circumferential direction. The outer housing 170 has a shape in which the first end face of a first cylindrical portion 171, which is a first side portion, fits along the outer peripheral surface of the damper case 13 of the cylinder portion 10, and the outer peripheral portion of the first cylindrical portion 171 is fixed to the damper case 13 by, for example, welding. A female thread 179 is formed on the inner peripheral surface of the outer housing 170. The outer circumferential surface 170a of the first cylindrical portion 171 is coated with a coating material. The coating material may be, for example, cationic electrodeposition coating, which has high corrosion resistance.

[0062] The inner housing 180 has a cylindrical portion 181 having a substantially cylindrical shape, and an annular portion 182 having an annular shape protruding from the inner circumferential surface of the cylindrical portion 181 toward the second inward direction. A male thread 183 is formed at the end on the first side of the cylindrical portion 181, and is fastened to a female thread 179 formed on the inner peripheral surface of the outer housing 170. A recess 184 recessed from the outer peripheral surface is formed in the cylindrical portion 181 at a portion on the second side of the male thread 183, and an O-ring 185 that seals between the outer peripheral surface of the inner housing 180 and the inner peripheral surface of the outer housing 170 is fitted in the recess 184. Further, a first engagement portion 186 recessed from the inner peripheral surface is formed around the entire circumference of the cylindrical portion 181 at the end portion on the second side.

[0063] ((Solenoid part 102)) The solenoid portion 102 has a cover portion 120 that covers the opening of the housing 160, and a clip 103 that determines the axial position of the cover portion 120 relative to the housing 160. When the solenoid portion 102 is energized, it pushes the plunger 117 toward the first side.

[0064] Clip 103 is a metal member whose cross-sectional shape when cut along a plane parallel to the second axial direction is a rectangle with the axial direction as the short side and the radial direction as the long side, and whose cross-sectional shape when cut along a plane perpendicular to the second axial direction is C-shaped.

[0065] Cover portion 120 has coil 121, covering portion 130 that holds coil 121 and covers the opening of housing 160, connector portion 122 for passing current through coil 121, and connection portion 123 that connects covering portion 130 and connector portion 122. Cover portion 120 is molded by insert molding in which resin heated to a softening temperature is filled into a mold at portions corresponding to covering portion 130, connector portion 122, and connection portion 123 with metallic coil 121 and surrounding portion 150 held in a mold. Therefore, covering portion 130, connector portion 122, and connection portion 123 are molded from molded resin. The connecting portion 123 protrudes outward in a rectangular parallelepiped shape from the outer periphery of the covering portion 130. The connector portion 122 is provided so as to protrude from a second outer end portion of the connecting portion 123 to the first side.

[0066] The covering portion 130 has a disk-shaped portion 131 that covers the opening of the housing 160, a surrounding portion 132 that protrudes from the disk-shaped portion 131 to the first side and covers the periphery of the coil 121, and a surrounding portion 150 that surrounds the second outer periphery of the housing 160.

[0067] A recess 140 recessed from the end face on the first side is formed on the outer periphery of the disk-shaped portion 131. The recess 140 is formed by a parallel surface 141 parallel to the second axial direction, an orthogonal surface 142 perpendicular to the second axial direction formed on the end portion on the second side, and a recess 143 recessed from the parallel surface 141 to the second inward direction.

[0068] Surrounding portion 132 is cylindrical, and is provided outside second fixed member 112 and inside housing 160. Surrounding portion 132 has coil 121 at a position overlapping with a moving area of ​​movable core 118 fixed to plunger 117 in the second axial direction. Additionally, a second engagement portion 135 recessed from the outer circumferential surface is formed around the entire circumference of the peripheral portion 132 at a portion on the second side from the center in the second axial direction. The second engagement portion 135 is formed at a position in the axial direction corresponding to the first engagement portion 186 formed on the cylindrical portion 181 of the inner housing 180. The clip 103 is fitted into the second engagement portion 135 and the first engagement portion 186.

[0069] The enclosure 150 has a cylindrical first cylindrical portion 151 arranged on the first side, a cylindrical second cylindrical portion 152 arranged on the second side, and a connection portion 153 connecting the first cylindrical portion 151 and the second cylindrical portion 152. The inner diameter of the first cylindrical portion 151 is larger than the outer diameter of the first cylindrical portion 171 of the outer housing 170 . The inner diameter of second cylindrical portion 152 is larger than the outer diameter of second cylindrical portion 172 of outer housing 170 and smaller than the outer diameter of first cylindrical portion 171 . The connecting portion 153 is inclined with respect to the axial direction so that the diameter of the inner surface gradually increases from the second side to the first side. The connecting portion 153 is disposed so as to face the inclined surface 173 of the first cylindrical portion 171.

[0070] A first protrusion 155 protruding from the inner circumferential surface toward the second inner side is provided at the end of the first side of the second cylindrical portion 152. The first protrusion 155 is rectangular parallelepiped and is formed on a part of the circumferential direction. The first protrusion 155 is fitted into a recess 172a formed in the outer housing 170, so that the circumferential position of the cover portion 120 with respect to the outer housing 170 is determined. Further, a second protrusion 156 that protrudes from the inner circumferential surface toward the second inside is provided at the end on the second side of the second cylindrical portion 152.

[0071] The surrounding part 150 may be formed of a metal material such as iron, stainless steel, aluminum, or brass. The surrounding part 150 is held by the disk-shaped part 131 by fitting the second protrusion 156 into the recess 143 of the disk-shaped part 131. Although the surrounding part 150 and the cover part 130 are integrated by insert molding as described above, the surrounding part 150 may be fitted into the recess 143 of the cover part 130 that has been molded in advance. When fitting the second protrusion 156 into the recess 143, the second end of the surrounding part 150 may be elastically deformed so as to expand. This makes it possible to assemble the surrounding part 150 to the outer housing 170 after the disk-shaped part 131 and the surrounding part 150 are firmly integrated. The disk-shaped part 131 and the surrounding part 150 may be connected by other methods such as adhesion or welding. The surrounding portion 150 is painted. The painting may be, for example, cathodic electrocoating, which has high corrosion resistance.

[0072] The seal member 190 can be, for example, an O-ring made of a rubber-based material. The inner diameter of the seal member 190 is smaller than the outer diameter of the first cylindrical portion 171 of the outer housing 170. The outer diameter of the seal member 190 is larger than the inner diameter of the first cylindrical portion 151 of the surrounding portion 150. When the cover portion 120 is attached to the outside of the outer housing 170 of the housing 160, the seal member 190 is sandwiched between the surrounding portion 150 and the outer housing 170, and contacts the inner circumferential surface, the first surface 176, and the second surface 177 of the first cylindrical portion 151 of the surrounding portion 150.

[0073] (Connection flow path portion 90) As shown in FIG. 2, the connection flow path portion 90 has a cylindrical portion 91 and a flange portion 92 that cylindrically protrudes from the outer circumferential surface of the cylindrical portion 91 to the second outer side around the entire circumference at the second end of the cylindrical portion 91. The outer diameter of the cylindrical portion 91 is smaller than the inner diameter of the protruding portion 174 of the outer housing 170 , and the inner diameter of the cylindrical portion 91 is smaller than the inner diameter of the main valve seat 53 . The outer diameter of the flange portion 92 is larger than the inner diameter of the protruding portion 174 of the outer housing 170 and smaller than the inner diameter of the first cylindrical portion 171. The flange portion 92 is disposed on the second side of the protruding portion 174 of the outer housing 170. A return hole 93 is formed in the flange portion 92 in the second axial direction. A plurality of return holes 93 are formed in the circumferential direction.

[0074] The second inner side of the cylindrical portion 91 communicates with the outer cylinder opening 12H on the first side, and communicates with the second inner side of the main valve seat 53 on the second side. The second inner side of the cylindrical portion 91 constitutes a part of the first flow path R1. The return hole 93 communicates with the case opening 13H on a first side and communicates with the annular gap S1 on a second side.

[0075] The damping force generating device 50 configured as above can be assembled, for example, by using the assembly method described below. That is, the worker assembles the connection flow passage portion 90, the main valve seat 53, the main valve 52, the elastic member 54, the guide member 61, the biasing member 75, the restricting member 72, the first spacer member 73A, the second spacer member 73B, the third spacer member 73C, the cap portion 80, and the first fixing member 111 inside the outer housing 170 fixed to the outer peripheral surface of the damper case 13, and then fastens the inner housing 180 to the outer housing 170. In addition, the control valve 70 is disposed so that the protruding portion 703 and the convex portion 706 of the control valve 70 are positioned between the biasing member 75 and the restricting member 72, and the coil spring 79 is disposed on the second inner side of the control valve 70. In addition, the pressing member 77 held by the plunger 117 is disposed so that the cylindrical portion 701 of the pressing member 77 is located on the second inner side of the coil spring 79 and the flange portion 773 is located on the second side of the coil spring 79 . Then, the spacer 113 and the second fixing member 112 are inserted onto the second side of the first fixing member 111, and the solenoid portion 102 is assembled. Before the solenoid portion 102 is assembled, the seal member 190 is fitted into the groove 175 of the outer housing 170.

[0076] In the damping force generating device 50 configured as above, an annular gap S1 is formed between the inner circumferential surface of the first cylindrical portion 171 of the outer housing 170 and the outer circumferential surface of the cylindrical portion 62 of the guide member 61. Also, as shown in FIG. 7 etc., a first flow path R1 is formed through which oil flows into the reservoir chamber R through the communication path L, the second inner side of the cylindrical portion 91 of the connection flow path portion 90, between the main valve 52 and the main valve seat 53, the horizontal hole 64 of the guide member 61, the annular gap S1, and the return hole 93 of the flange portion 92 of the connection flow path portion 90. As shown in FIG. 7 etc., a second flow path R2 is formed, which branches off from the upstream of the main valve 52 in the first flow path R1, passes through the inlet hole 526 in the bottom 522 of the main valve 52, the through hole 69 in the top 65 of the guide member 61, the second inner side of the third cylindrical portion 83 of the cap portion 80, the second radial groove 85, and the second axial groove 84, reaches the annular gap S1, and merges with the first flow path R1.

[0077] Further, the outer peripheral surface of the cylindrical portion 521 of the main valve 52 and the inner peripheral surface of the cylindrical portion 62 of the guide member 61 are sealed by a seal member 55. In other words, a seal mechanism 56 that seals between the outer peripheral surface of the cylindrical portion 521 of the main valve 52 and the inner peripheral surface of the cylindrical portion 62 of the guide member 61 is configured by the groove 525 formed in the outer peripheral surface of the cylindrical portion 521 of the main valve 52 and the seal member 55. Therefore, the guide member 61 forms a back pressure chamber 61P, at a portion inside the guide member 61 that is on the second side of the main valve 52, that applies oil pressure (hereinafter, may be referred to as "back pressure") from the second side opposite the main valve seat 53 to the main valve 52.

[0078] [Adjustment operation of damping force adjuster 60] Next, the adjustment operation in the damping force adjuster 60 will be described. By pressing the pressing member 77 toward the first side, the control valve 70 is pressed against the second protrusion 663 of the guide member 61. The pressing force of the pressing member 77, in other words, the thrust force of the solenoid portion 102 (see FIG. 2), changes depending on the amount of current flowing through the solenoid portion 102.

[0079] For example, in the damping force adjusting section 60, a state in which the pressing force of the pressing member 77 is maximized is created. At this time, the control valve 70 is most strongly pressed against the second protruding portion 663 of the guide member 61, and the second flow path R2 is closed.

[0080] Also, for example, in the damping force adjusting section 60, a state is created in which the pressing force of the pressing member 77 is minimized. At this time, in the damping force adjusting section 60, the control valve 70 is separated from the second protruding portion 663 of the guide member 61, and the second flow path R2 is opened.

[0081] Furthermore, for example, in the damping force adjustment unit 60, the pressing force of the pressing member 77 is set to a state between the smallest and largest states. In this state, in the damping force adjustment unit 60, the control valve 70 is farther away from the second protrusion 663 of the guide member 61 than in the state where the pressing force is largest, and is closer to the second protrusion 663 than in the state where the pressing force is smallest.

[0082] [Shock Absorber 2 Operation] First, the operation of the shock absorber 2 during the extension process will be described. During the extension stroke, the rod 20 moves to the other side (see FIG. 2) relative to the cylinder 11. At this time, the piston valve 32 remains blocking the piston oil passage port 311. Furthermore, as the piston portion 30 moves to the other side, the volume of the second oil chamber Y2 decreases. Then, the oil in the second oil chamber Y2 flows out from the communication hole 11H to the communication passage L.

[0083] Furthermore, the oil flows into the damping force generating device 50 through the communication passage L and the outer cylinder opening 12H. In the damping force generating device 50, the oil first flows into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90. Then, in the damping force generating device 50, a damping force is generated in the main valve 52 or the control valve 70. The flow of the oil at this time will be described in detail later.

[0084] Thereafter, the oil that has flowed into the main valve 52 or the control valve 70 flows out into the annular gap S1. Furthermore, the oil passes through the return hole 93 of the flange portion 92 of the connection flow path portion 90 and flows into the reservoir chamber R from the case opening 13H. Furthermore, the pressure in the first oil chamber Y1 becomes lower relative to the pressure in the reservoir chamber R. Therefore, the oil in the reservoir chamber R passes through the bottom portion 40 and flows into the first oil chamber Y1.

[0085] Next, the operation of the shock absorber 2 during the compression stroke will be described. During the compression stroke, the rod 20 moves relative to the cylinder 11 to one side (see FIG. 2). In the piston portion 30, the piston valve 32 that closes the piston oil passage port 311 opens due to the pressure difference between the first oil chamber Y1 and the second oil chamber Y2. Then, the oil in the first oil chamber Y1 flows out through the piston oil passage port 311 to the second oil chamber Y2. Here, the rod 20 is disposed in the second oil chamber Y2. Therefore, the oil flowing from the first oil chamber Y1 to the second oil chamber Y2 is in excess by the volume of the rod 20. Therefore, an amount of oil equivalent to the volume of the rod 20 flows out from the communication hole 11H to the communication passage L.

[0086] Furthermore, the oil flows into the damping force generator 50 through the communication path L and the outer cylinder opening 12H. The flow of oil in the damping force generator 50 is similar to the flow of oil during the extension stroke described above. That is, in the shock absorber 2 of the first embodiment, the direction in which the oil flows in the damping force generator 50 is the same during both the compression stroke and the extension stroke.

[0087] As described above, in the shock absorber 2, the damping force generating device 50 generates a damping force during both the compression stroke and the expansion stroke. The generation of the damping force by the damping force generating device 50 will be described in detail below.

[0088] (normal time) The flow of oil in the normal state where the solenoid portion 102 is in an energized state and the pressing force of the pressing member 77 acts will be described.

[0089] ((at low speed)) FIG. 6 is a diagram showing an example of the oil flow when the moving speed of the piston portion 30 (see FIG. 1) is low in a state in which the pressing force of the pressing member 77 is at its smallest. 6, when the movement speed of the piston portion 30 is low, the oil that has flowed to the second inner side of the cylindrical portion 91 of the connection flow path portion 90 flows into the second inner side of the main valve seat 53. Here, because the movement speed of the piston portion 30 is low, no flow of oil that opens the main valve 52 is generated in the first flow path R1 (see FIG. 7). On the other hand, the oil that has flowed into the second inner side of the main valve seat 53 flows through the second flow path R2 as shown by the arrows in Fig. 6. Then, the oil flows out into the reservoir chamber R from the annular gap S1. As described above, when the moving speed of the piston portion 30 is low, the flow of oil is restricted by the gap between the control valve 70 and the second protruding portion 663 of the guide member 61, thereby generating a damping force.

[0090] ((at high speed)) FIG. 7 is a diagram showing an example of the oil flow when the moving speed of the piston portion 30 (see FIG. 1) is high in a state in which the pressing force of the pressing member 77 is set to the smallest. 7, when the moving speed of the piston portion 30 is high, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90 flows into the second inner side of the main valve seat 53. The oil that has flowed into the second inner side of the main valve seat 53 opens the main valve 52 and flows out into the reservoir chamber R. Furthermore, even when the moving speed is high, the oil that flows into the second inner side of the main valve seat 53 flows to the annular gap S1 while generating a pressure difference due to the flow rate being restricted by the gap between the control valve 70 and the second protrusion 663 of the guide member 61, just as when the moving speed is low, and then flows out into the reservoir chamber R.

[0091] As described above, when the moving speed of the piston portion 30 is high, the damping force is generated mainly by the flow of oil in the first flow passage R1 passing between the main valve 52 and the main valve seat 53.

[0092] The oil that has flowed into the second inner side of the main valve seat 53 transmits pressure to the back pressure chamber 61P through the introduction hole 526 in the bottom portion 522 of the main valve 52. However, the second flow path R2 that communicates with the back pressure chamber 61P is opened by the control valve 70. Therefore, the pressure in the back pressure chamber 61P is lower than when the control valve 70 is pressed against the second protruding portion 663 of the guide member 61. The main valve 52 that receives pressure from the back pressure chamber 61P is more likely to open the first flow path R1. Therefore, when the pressing force of the pressing member 77 is at its smallest, the damping force generated by the flow of oil in the first flow path R1 that opens the main valve 52 is lower than when the pressing force of the pressing member 77 is at its largest.

[0093] ((at low speed)) FIG. 8 is a diagram showing an example of the oil flow when the moving speed of the piston portion 30 (see FIG. 1) is low in a state in which the pressing force of the pressing member 77 is maximized. 8, when the movement speed of the piston portion 30 is low, the oil that has flowed to the second inner side of the cylindrical portion 91 of the connection flow path portion 90 flows into the second inner side of the main valve seat 53. Here, because the movement speed of the piston portion 30 is low, the main valve 52 is opened and no flow of oil flows through the first flow path R1 (see FIG. 9). On the other hand, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow path portion 90 flows through the second flow path R2 that passes through the introduction hole 526 of the bottom portion 522 of the main valve 52, as shown by the arrows in Fig. 8. Then, the oil flows out from the annular gap S1 into the reservoir chamber R.

[0094] As described above, when the moving speed of the piston portion 30 is low, the damping force is generated by the oil flowing through the second flow path R2 while opening the control valve 70. The damping force generated when the oil flows through the second flow path R2 is higher than that when the control valve 70 is separated from the second protrusion portion 663 of the guide member 61.

[0095] ((at high speed)) FIG. 9 is a diagram showing an example of the oil flow when the moving speed of the piston portion 30 (see FIG. 1) is high in a state in which the pressing force of the pressing member 77 is maximized. 9, when the moving speed of the piston portion 30 is high, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90 flows into the second inner side of the main valve seat 53. The oil that has flowed into the second inner side of the main valve seat 53 opens the main valve 52 and flows out into the reservoir chamber R. Furthermore, even when the moving speed is high, the oil that flows into the second inner side of the cylindrical portion 91 of the connection flow path portion 90 flows to the annular gap S1 while generating a pressure difference due to the flow rate being restricted by the gap between the second protrusion portion 663 of the guide member 61 and the control valve 70, just as when the pressing force of the pressing member 77 is at its smallest, and then flows out into the reservoir chamber R. As described above, when the moving speed of the piston portion 30 is high, the damping force is generated mainly by the flow of oil in the first flow passage R1 passing between the main valve 52 and the main valve seat 53.

[0096] The oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90 transmits pressure to the back pressure chamber 61P through the introduction hole 526 of the bottom portion 522 of the main valve 52. The second flow passage R2 that communicates with the back pressure chamber 61P is in a state in which the control valve 70 is pressed by the second protruding portion 663 of the guide member 61. Therefore, the pressure in the back pressure chamber 61P is higher than when the second flow passage R2 is open as shown in FIG. 7. The main valve 52, which receives a force from the oil in the back pressure chamber 61P, is less likely to open the first flow passage R1. Therefore, when the pressing force of the pressing member 77 is at its largest, the damping force generated by the flow of oil in the first flow passage R1 that opens the main valve 52 is higher than when the pressing force of the pressing member 77 is at its smallest.

[0097] As described above, in the shock absorber 2, the damping force at low speeds and the damping force at high speeds are both adjusted by operating the pressing member 77. That is, in the shock absorber 2, the pressing force of the control valve 70 against the second protruding portion 663 of the guide member 61 is changed by the pressing member 77, thereby adjusting the flow path area of ​​the second flow path R2, which is the flow path for oil at low speeds, and the flow path area of ​​the second flow path R2 that adjusts the pressure of the back pressure chamber 61P related to the flow path area for oil at high speeds.

[0098] In the above-mentioned operation example, two patterns, that is, the smallest and largest pressing force of the pressing member 77, have been described, but the present invention is not limited to the above-mentioned two patterns. The pressing force of the pressing member 77 can be arbitrarily set within an adjustable range according to the amount of current to the solenoid portion 102, in other words, the thrust of the solenoid portion 102. In accordance with this setting, the damping force adjustment portion 60 can adjust the damping force at low speed and the damping force at high speed in multiple stages.

[0099] (When abnormality occurs) Next, we will explain the flow of oil in an abnormal state in which the solenoid portion 102 is in a non-energized state and the pressing force of the pressing member 77 does not act. An example of a case in which the solenoid portion 102 is in a non-energized state is when the current supply to the coil of the solenoid portion 102 is stopped due to, for example, a break in the wire. FIG. 10 is a diagram showing an example of the oil flow when the solenoid portion 102 is in a non-energized state and the moving speed of the piston portion 30 (see FIG. 1) is low. FIG. 11 is a diagram showing an example of the flow of oil when the solenoid portion 102 is in a non-energized state and the moving speed of the piston portion 30 is high.

[0100] 10 and 11, when the solenoid portion 102 is in a non-energized state, the plunger 117 is pushed back to the second side by the coil spring 79. Accordingly, the pressing member 77 fixed to the plunger 117 is pressed against the cap portion 80.

[0101] ((at low speed)) As shown in FIG. 10, when the moving speed of the piston portion 30 is low, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connecting flow path portion 90 flows through the second flow path R2 and flows out into the reservoir chamber R from the annular gap S1. When the moving speed of the piston portion 30 is low, the damping force is generated by the gap formed between the flange portion 773 of the pressing member 77 and the cap portion 80, that is, by the flow of oil in the groove portion 831.

[0102] ((at high speed)) As shown in FIG. 11, when the moving speed of the piston portion 30 is high, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90 opens the main valve 52 and flows out into the reservoir chamber R. Furthermore, even when the moving speed is high, the oil that flows into the second inner side of the cylindrical portion 91 of the connection flow path portion 90 flows to the annular gap S1 while generating a pressure difference due to the flow rate being restricted by the groove portion 831 formed in the cap portion 80, just as when the moving speed is low, and then flows out into the reservoir chamber R. As described above, when the moving speed of the piston portion 30 is high, the damping force is generated mainly by the flow of oil in the first flow path R1.

[0103] Here, the oil that has flowed into the second inner side of the cylindrical portion 91 of the connection flow passage portion 90 transmits pressure to the back pressure chamber 61P through the introduction hole 526 of the bottom portion 522 of the main valve 52. The back pressure chamber 61P is connected to the annular gap S1 through the second flow passage R2. The flow of oil between the back pressure chamber 61P and the annular gap S1 needs to pass through the groove portion 831 formed in the cap portion 80. The flow of oil is restricted by the groove portion 831 formed in the cap portion 80, so that the outflow of oil from the back pressure chamber 61P is suppressed, and the pressure of the back pressure chamber 61P is maintained in a state higher than the state in which the pressing force of the pressing member 77 is the smallest, as shown in FIG. 7. The main valve 52, which receives a force from the oil in the back pressure chamber 61P, is relatively difficult to open the first flow passage R1. Therefore, when the solenoid portion 102 is in a non-energized state, the damping force generated by the flow of oil in the first flow passage R1 that opens the main valve 52 is relatively high.

[0104] As described above, in the shock absorber 2 of the first embodiment, even in an abnormal state in which current is not applied to the solenoid portion 102, the damping force at both low speeds and high speeds is made relatively high.

[0105] (Difference between normal and abnormal situations) When the resultant force of the force of the oil passing through the through hole 69 of the guide member 61 moving the control valve 70 to the second side and the force of the coil spring 79 exceeds the pressing force of the pressing member 77, the control valve 70 moves to the second side even if the thrust of the solenoid unit 102 is generated. In particular, when the thrust of the solenoid unit 102 is relatively small, such as in the state in which the pressing force of the pressing member 77 is smallest as shown in Figures 6 and 7, if the pressure of the oil passing through the through hole 69 of the guide member 61 becomes high, the control valve 70 temporarily moves to the second side.

[0106] In the damping force generating device 50, even if the control valve 70 moves to the second side, the restricting member 72 suppresses the movement of the control valve 70 to the second side. In other words, the control valve 70 receives a force from the restricting member 72 in the direction toward the first side when the protruding portion 703 comes into contact with the restricting member 72, and is suppressed from moving to the second side.

[0107] Furthermore, the cylindrical portion 771 and the bottom portion 772 of the pressing member 77 are disposed on the second inner side of the cylindrical portion 701 and the conical portion 702 of the control valve 70, and the diameter of the outer periphery of the flange portion 773 of the pressing member 77 is equal to or smaller than the outer diameter of the cylindrical portion 701 of the control valve 70, so that the pressing member 77 is less likely to be subjected to the force of the oil flowing through the through hole 69 of the guide member 61 toward the third cylindrical portion 83 of the cap portion 80. As a result, the pressing member 77 is also restrained from moving toward the second side, so that it tends to remain in the normal operating position stably, and the pressing member 77 is less likely to be pressed against the cap portion 80, which is the operating position during an abnormality.

[0108] Thus, in the damping force generating device 50 according to this embodiment, even if the resultant force of the force of the oil moving the control valve 70 to the second side and the force of the coil spring 79 exceeds the thrust of the solenoid unit 102 during normal operation, the pressing member 77 is unlikely to be pressed against the cap unit 80. That is, in the damping force generating device 50, unlike the operation during abnormal operation, during normal operation, the pressing member 77 is unlikely to be pressed against the cap unit 80. As a result, the damping force generating device 50 can prevent the mechanism from operating during abnormal operation even though the mechanism can operate normally, and can operate during abnormal operation when an abnormality occurs in the mechanism. Also, even if the flow path cross-sectional area of ​​the groove 831 formed in the cap unit 80 is changed in order to adjust the damping force generated during abnormal operation, the change can be prevented from affecting the damping force during normal operation.

[0109] As described above, the damping force generating device 50 includes the main valve 52 (an example of a pressure control valve body) that opens and closes the first flow path R1 (an example of a flow path) by being seated on and separated from the main valve seat 53 (an example of a valve seat), and the control valve 70 (an example of a pilot valve body) that opens and closes the first flow path R1 downstream of a portion that is opened and closed by the main valve 52. The damping force generating device 50 also includes a solenoid unit 102 (an example of an actuator) that can drive the control valve 70 in a valve closing direction, and a guide member 61 that guides the movement of the main valve 52 in the second axial direction and has a second flow path R2 (a flow path toward the control valve 70) and a second protrusion 663 (an example of a pilot valve seat) at a top 65. The damping force generating device 50 also includes an elastic member 54 that biases the main valve 52 toward the main valve seat 53, and a central portion 66 (an example of a centering portion) that is integral with the guide member 61 and has a first surface 661 (an example of an axial movement restricting portion) that centers the inner circumference of the elastic member 54 and restricts second axial movement of the elastic member 54.

[0110] According to the damping force generating device 50 configured as above, the cylindrical portion 62 which is a portion that guides the movement of the main valve 52, and the second protruding portion 663 which is a portion on which the control valve 70 is seated are both formed on the guide member 61. Therefore, it is possible to generate and adjust the damping force with a simpler configuration than a configuration in which the portion that guides the movement of the main valve 52 and the portion on which the control valve 70 is seated are separate parts. In addition, the guide member 61 also has a portion that restricts the movement of the elastic member 54, so that it is possible to have a simpler configuration than a configuration in which a separate part is provided from the guide member 61 to restrict the movement of the elastic member 54.

[0111] Furthermore, the guide member 61 is formed in a bottomed cylindrical shape consisting of a top 65 (an example of a bottom) and a cylindrical portion 62 (an example of a tube portion), and guides the main valve 52 on the inner periphery side of the cylindrical portion 62, with the inside of the top 65 protruding more on the inner periphery side than on the outer periphery side. Furthermore, a recess 664 is formed between the outer periphery side of the top 65 and the second protruding portion 663. As a result, the guide member 61, as a single component, has the function of guiding the movement of the main valve 52, the function of serving as a valve seat for the control valve 70, and the function of restricting the movement of the elastic member 54.

[0112] Moreover, the cylindrical portion 62 and / or the main valve 52 has a groove 525 (an example of a circumferential groove) on the sliding surface and a seal member 55 having a joint 550 disposed in the groove 525. This seals the gap between the outer circumferential surface of the main valve 52 and the cylindrical portion 62 of the guide member 61, so that back pressure can be applied to the main valve 52 with high accuracy, and a damping force can be generated with high accuracy.

[0113] The groove 525 is formed with an axial length (in other words, the size in the second axial direction) longer than the seal member 55 and a depth smaller than the minimum inner diameter of the seal member 55. In other words, the size of the groove 525 in the second axial direction (in other words, the movement direction) is larger than the size of the seal member 55, and the depth is deeper than the size of the seal member 55 in the recess direction (in other words, the second radial direction). This makes it possible to change the position and shape of the seal member 55 in the groove 525 according to the pressure in the valve closing direction (in other words, the back pressure) on the main valve 52. For example, the back pressure can bring the seal member 55 into firm contact with the end face on the first side of the groove 525, and the oil that has entered the gap between the inner peripheral surface of the seal member 55 and the bottom of the groove 525 can bring the outer peripheral surface of the seal member 55 into firm contact with the inner peripheral surface of the cylindrical portion 62 of the guide member 61. Therefore, the groove 525 and the seal member 55 can adjust the back pressure with high accuracy.

[0114] The gap between the elastic member 54 and the central portion 66 of the apex 65 of the guide member 61 is smaller than the gap between the elastic member 54 and the guide member 61. This prevents the elastic member 54 from moving in the second radial direction, and there is no risk of the outer edge of the elastic member 54 coming into contact with the inner circumferential surface of the guide member 61.

[0115] <Second embodiment> FIG. 12 is a diagram showing an example of a schematic configuration of an elastic member 200 according to the second embodiment. The elastic member 200 according to the second embodiment is different from the elastic member 54 according to the first embodiment in that it has an arm portion 201 corresponding to the arm portion 542. The differences from the first embodiment will be described below. The same reference numerals are used for the same parts in the first and second embodiments, and detailed descriptions thereof will be omitted.

[0116] The arm portion 201 protrudes from the annular portion 541 toward the second inside, and the central portion in the second radial direction is wider in the circumferential direction than the base end and tip end, which are the portions on the annular portion 541 side. Three arm portions 201 are formed at equal intervals in the circumferential direction, and the tips of the three arm portions 201 are connected. Each arm portion 201 is formed with a sector-shaped notch 202. A central hole 203, which is a through hole in the second axial direction, is formed in the second inner portion where the tips of the three arm portions 201 are connected.

[0117] The elastic member 200 configured as above has an axisymmetric shape. In other words, the elastic member 200 has a symmetric shape with respect to a plane parallel to the second axis direction. The diameter of the central hole 203 is larger than the outer diameter of the first protruding portion 662 of the guide member 61 and smaller than the outer diameter of the first surface 661. The elastic member 200 configured as above can apply a uniform force to the main valve 52. The number of arms 201 is not limited to three. [Explanation of symbols]

[0118] 1...suspension device, 2...shock absorber, 10...cylinder portion, 11...cylinder, 20...rod, 30...piston portion, 50...damping force generating device, 51...main valve portion, 52...main valve (an example of a pressure control valve body), 53...main valve seat (an example of a valve seat), 54...elastic member, 55...sealing member, 60...damping force adjusting portion, 61...guide member, 61P...back pressure chamber, 62...cylindrical portion (an example of a tube portion), 65...top portion (an example of a bottom portion), 66...center portion (an example of a centering portion), 67...outer periphery, 70...control valve (an example of a pilot valve body), 525...groove (an example of a circumferential groove), 550...joint, 661...first surface (an example of an axial movement restricting portion), 662...first protruding portion, 663...second protruding portion (an example of a pilot valve seat), 664...recess, R1...first flow path, R2...second flow path

Claims

1. a pressure control valve body that opens and closes a flow path by being seated on and removed from a valve seat; a pilot valve body that opens and closes a downstream portion of the flow passage that is opened and closed by the pressure control valve body; an actuator capable of driving the pilot valve body in a valve closing direction; a guide member which guides the pressure control valve element against axial movement and has a flow passage leading to the pilot valve element and a pilot valve seat; an elastic member that biases the pressure control valve body toward the valve seat; a centering portion provided integrally with the guide member, the centering portion including an axial movement restricting portion that centers an inner periphery of the elastic member and restricts axial movement of the elastic member; A damping force adjustment valve having a damping force adjusting mechanism.

2. The guide member is formed in a bottomed cylindrical shape consisting of a bottom portion and a cylindrical portion, and guides the pressure control valve body on the inner peripheral side of the cylindrical portion, and the inside of the bottom portion protrudes more on the inner peripheral side than on the outer peripheral side. The damping force control valve according to claim 1 .

3. A recess is formed between the outer circumferential side of the bottom portion and the pilot valve seat. The damping force control valve according to claim 2 .

4. the cylindrical portion and / or the pressure control valve body has a sealing member having a circumferential groove on a sliding surface and a gap disposed in the circumferential groove; The damping force control valve according to claim 2 .

5. The circumferential groove is formed with an axial length longer than the seal member and a depth smaller than the minimum inner diameter of the seal member. The damping force control valve according to claim 4.

6. a gap between the elastic member and the centering portion is smaller than a gap between the elastic member and the guide member; The damping force control valve according to claim 1 .

7. The elastic member has a point-symmetric or line-symmetric shape. The damping force control valve according to claim 1 .

Images