Shock absorber

Abstract

To provide a shock absorber which can achieve reduction of the price.SOLUTION: A shock absorber has: a holding member which is formed into a cylindrical shape having a first groove on its peripheral surface and rigidly coupled to an outer periphery of a cylinder part; an exterior component which is formed into a cylindrical shape having a second groove, which may face the first groove, on its outer peripheral surface and at least partially exposed from an outer peripheral surface of the cylinder part; a spring member which applies a force acting in a direction away from the cylinder part; and a hook member which is disposed spanning the first groove and the second groove in a state that the first groove and the second groove face each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a shock absorber. [Background technology]

[0002] For example, the hydraulic shock absorber described in Patent Document 1 includes an outer damping unit that is provided outside the cylinder unit and generates a damping force. The outer damping unit has a plunger that moves back and forth along a second axial direction and a solenoid unit that uses an electromagnet to move the plunger back and forth. The outer damping unit also has a valve body that is attached to the tip of the plunger and presses the control valve with a force generated in response to the amount of current supplied to the solenoid unit. The plunger and solenoid unit function as an actuator that moves the valve body. In addition, in the outer damping unit, a solenoid case that houses the plunger and solenoid unit is fastened with screws to an outer housing that is fixed to the cylinder unit by welding, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2022-129991 Summary of the Invention [Problem to be solved by the invention]

[0004] When screw fastening is used to fix an object provided outside the cylinder portion (the outer damping portion in Patent Document 1) to the cylinder portion, processing is required to form male and female threads. Therefore, the device described in Patent Document 1 has room for improvement in terms of cost reduction. SUMMARY OF THE INVENTION An object of the present invention is to provide a shock absorber that can be manufactured at low cost. [Means for solving the problem]

[0005] The present invention, which was completed with this objective in mind, is a shock absorber comprising: a retaining member formed in a cylindrical shape with a first groove on its inner surface and rigidly connected to the outer periphery of a cylinder portion; an exterior part formed in a cylindrical shape with a second groove on its outer periphery that can face the first groove and at least a portion of which is exposed from the outer periphery of the cylinder portion; a spring member that applies a force in a direction away from the cylinder portion; and a clasp member that is arranged across both the first groove and the second groove so that they face each other. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a shock absorber that can be manufactured at low cost. [Brief explanation 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. [Figure 2] 1 is a diagram showing an example of a cross section of a damping force generating device according to a first embodiment. [Figure 3] 4 is a diagram showing an example of a view of the valve body as seen from the first side in the second axial direction. FIG. [Figure 4] FIG. 3 is a diagram illustrating an example of a pressure operation chamber and a flow path. [Figure 5] 6 is a diagram showing the relationship between the value of a current flowing through a coil and the opening area of ​​a first flow path and the opening area of ​​a second flow path. FIG. [Figure 6] FIG. 10 is a diagram illustrating an example of oil flow during an abnormality. [Figure 7] FIG. 6 is a diagram showing an example of a cross section of a solenoid valve according to a second embodiment. [Figure 8] FIG. 10 is a diagram showing an example of a cross section of a solenoid valve according to a third embodiment. [Figure 9] FIG. 10 is a diagram showing an example of a cross section of a shock absorber according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[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 system 1 according to the first embodiment. The suspension system 1 is a suspension used in vehicles such as passenger cars, 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 seat 4 that supports the end of the coil spring 3 on one side in the axial direction (the lower side in Fig. 1) of a rod 20, which will be described later, and an upper spring seat 5 that supports the 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 attaching the suspension device 1 to a vehicle, a wheel side bracket 7 for attaching 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." Furthermore, one side in the axial direction (the lower side in FIG. 1) and the other side in the axial direction (the upper side in FIG. 1) may be simply referred to as the "one side" and the "other side," respectively. Furthermore, a direction intersecting the axial direction (for example, 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 stores oil, and a rod 20 that has one side that protrudes from the cylinder portion 10 and one side that is slidably inserted into 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 also 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 stores oil, an outer cylindrical body 12 that is provided on the outside of the cylinder 11, and a damper case 13 that is provided on the outside of the cylinder 11 and further outside the outer cylindrical 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 connects the inside and the outside is formed at the other end. The outer cylinder body 12 is formed in a cylindrical shape. The outer cylinder body 12 forms a communication path L between the outer cylinder body 12 and the cylinder 11. The outer cylinder body 12 also has an outer cylinder body opening 12H at a position facing the damping force generator 50. A connection flow path portion 160 (described later, see FIG. 2) of the damping force generator 50 is fitted into the outer cylinder body opening 12H.

[0013] The damper case 13 is formed in a cylindrical shape. A reservoir chamber R in which oil is stored is formed between the damper case 13 and the outer cylinder body 12. The reservoir chamber R absorbs oil from 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 generator 50. The damper case 13 also has a case opening 13H at a position facing the damping force generator 50.

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

[0015] The piston portion 30 has 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 an axially provided fixing member 44. The bottom portion 40 separates the first oil chamber Y1 from 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 view of the valve body 120 as seen from the first side in the second axial direction. As shown in FIG. 2, the damping force generating device 50 includes a solenoid valve 100, a holding member 90 that holds the solenoid valve 100, and a ring 95 that positions the solenoid valve 100 relative to the holding member 90.

[0018] (holding member 90) The retaining member 90 is a cylindrical member. The retaining member 90 is disposed so that the center line direction coincides with the radial direction shown in Fig. 1. The end face of the retaining member 90 on the cylinder portion 10 side is shaped to fit along the outer peripheral surface of the damper case 13, and the outer peripheral portion of the end of the retaining member 90 on the damper case 13 side is fixed to the damper case 13 by, for example, welding. The holding member 90 has a recess 91 recessed from the inner peripheral surface along the entire periphery.

[0019] In the following description, the center line direction of the holding member 90 (i.e., the direction intersecting the axial direction of the cylinder portion 10 (see FIG. 1)) may be referred to as the "second axial direction." In addition, the center axis side of the cylinder portion 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 center axis of the cylinder portion 10 (the upper side of the damping force generating device 50 in FIG. 2) may be referred to as the "second side." In addition, the direction intersecting the center line direction of the holding member 90 (for example, the perpendicular direction) may be referred to as the "second radial direction." In addition, in the second radial direction, the center line side of the holding member 90 may be referred to as the "second inner side," and the side away from the center line of the holding member 90 may be referred to as the "second outer side."

[0020] (Ring 95) The ring 95 is a member whose cross section when cut along a plane parallel to the second axis direction is circular. The cross section of the ring 95 when cut along a plane perpendicular to the second axis direction is C-shaped. However, the shape of the ring 95 is not particularly limited. The ring 95 may be rectangular. The ring 95 may be, for example, a metal member. The ring 95 is fitted into a recess 177 of the housing 170 and a recess 91 of the holding member 90, which will be described later.

[0021] (Solenoid valve 100) The solenoid valve 100 includes a fixed part 110, a valve element 120 movable relative to the fixed part 110, a coil unit 130, an orifice plate 140 having a valve seat for the valve element 120, a partition member 150 that defines a pressure operation chamber 190 (described later), and a connection flow path part 160. The solenoid valve 100 also includes a housing 170 that accommodates the fixed part 110, the valve element 120, a coil 131 (described later), the orifice plate 140, and the partition member 150, and a ring 180 that positions the coil unit 130 in the second axial direction relative to the housing 170. The fixed part 110, the valve element 120, the coil unit 130, and the housing 170 constitute a solenoid actuator 105.

[0022] ((Fixed part 110)) The fixing portion 110 has a first fixing member 111 provided on the first side and a second fixing member 112 provided on the second side of the first fixing member 111. The first fixing member 111 is made of a magnetic material such as iron and is formed into a cylindrical shape. The first fixing member 111 is cylindrical and has a protruding portion 115 that protrudes in an annular shape from the outer circumferential surface at the end portion on the first side toward the second outside. The protruding portion 115 has a notch 116 formed by cutting out a portion of the protruding portion 115 in the circumferential direction. The end portion on the second side of the first fixing member 111 is formed so that the diameter of the outer circumferential surface gradually decreases from the first side to the second side. The first fixing member 111 is press-fitted into the orifice plate 140 .

[0023] The second fixing member 112 is made of a magnetic material such as iron, and has a cylindrical portion 117 and an annular flange 118 that protrudes outward from the second end of the cylindrical portion 117. The inner diameter of the cylindrical portion 117 is smaller than the inner diameter of the first fixing member 111 . The flange 118 has a notch 119 formed by cutting out a portion of the flange 118 in the circumferential direction. The second fixing member 112 is held by a covering portion 132 of the coil unit 130, which will be described later.

[0024] ((Valve body 120)) The valve body 120 has two cylindrical portions with different diameters, a first cylindrical portion 121 and a second cylindrical portion 122. The first cylindrical portion 121 is located closer to the first side than the second cylindrical portion 122. The diameter of the first cylindrical portion 121 is smaller than the diameter of the second cylindrical portion 122. The diameter of the first cylindrical portion 121 is slightly smaller than the inner diameter of the partition member 150. The diameter of the second cylindrical portion 122 is smaller than the inner diameter of the first fixing member 111 and the inner diameter of the cylindrical portion 117 of the second fixing member 112, but larger than the inner diameter of the partition member 150. The second cylindrical portion 122 has a groove 122g recessed from the outer peripheral surface along a portion of its circumferential direction. The groove 122g is formed from the first end face of the second cylindrical portion 122 to the second end face. The valve body 120 may be provided in a cylindrical shape with the same diameter, and the groove 122g does not necessarily have to be formed.

[0025] Furthermore, the valve body 120 has a conical portion 123 that protrudes toward the first side from the first end of the first cylindrical portion 121. A tip portion 124, which is the first end of the conical portion 123, has a spherical curved surface. The first cylindrical portion 121, the second cylindrical portion 122, and the conical portion 123 are integrally molded using a magnetic material so that their center lines are aligned. The valve body 120 is disposed on the second inner side of the fixed portion 110 so that its center line is aligned with the second axial direction.

[0026] An oblique hole 125 is formed inside the valve body 120 in a direction inclined with respect to the center line. The oblique hole 125 is a hole that penetrates the conical portion 123, the first cylindrical portion 121, and the second cylindrical portion 122, with a first opening 126, which is an opening on the first side, being formed in the outer peripheral surface of the conical portion 123, and a second opening 127, which is an opening on the second side, being formed in the outer peripheral surface of the second cylindrical portion 122. It can be exemplified that a plurality of oblique holes 125 (two in FIG. 3) are formed. However, there may be only one oblique hole 125. Furthermore, although the oblique hole 125 is linear in this embodiment, it does not have to be linear.

[0027] ((Coil unit 130)) The coil unit 130 includes a coil 131, a covering portion 132 that covers and protects the outer periphery of the coil 131, and a connector portion 133 that applies electricity to the coil 131. The coil 131 can be, for example, an enameled wire made of copper wire coated with an insulating film. The end of the coil 131 is connected to a connector part 133, and generates a magnetic field when a current is passed through it.

[0028] Covering portion 132 is formed using a non-magnetic and insulating material, and covers the periphery of coil 131, the periphery of second fixing member 112, and the periphery of connector portion 133. Covering portion 132 covers the opening on the second side of housing 170. Covering portion 132 has a recess 135 recessed from the outer circumferential surface formed around the entire periphery in a portion on the second side of flange 118 of second fixing member 112. Recess 135 is formed at a position in the second axial direction that corresponds to recess 176 formed in housing 170. A ring 180 is fitted into recess 135 and recess 176.

[0029] The covering portion 132 holds the second fixed member 112. Therefore, the coil unit 130 and the second fixed member 112 function as a fixed core assembly 137 that includes the coil 131 and forms a pressure operation chamber 190 (see FIG. 4) between the coil unit 130 and the orifice plate 140.

[0030] ((Orifice plate 140)) The orifice plate 140 has a cylindrical columnar portion 141 and a protruding portion 143 that protrudes cylindrically from an end face 142 on the second side of the outer periphery of the columnar portion 141 to the second side. The outer diameter of the protruding portion 143 is the same as the outer diameter of the columnar portion 141. The inner diameter of the protruding portion 143 is smaller than the outer diameter of the first fixing member 111, and the first fixing member 111 can be press-fitted into the second inner side of the protruding portion 143. However, the inner diameter of the protruding portion 143 may be equal to or larger than the outer diameter of the first fixing member 111, and the first fixing member 111 may be bonded to the second inner side of the protruding portion 143 with an adhesive or the like. A partition member 150 is sandwiched between the first fixing member 111 and an end face 142 on the second side of the columnar portion 141 of the orifice plate 140.

[0031] A recess 144 recessed from an end face 142 on the second side toward the first side is formed in the center of the columnar portion 141. The recess 144 is conical. The columnar portion 141 also has a flow hole 145 formed therein, which allows oil to flow between a portion on the first side of the columnar portion 141 and the recess 144. The flow hole 145 is columnar, and the opening on the second side of the flow hole 145 is set to a size that allows it to be blocked by the tip end 124 of the valve body 120.

[0032] Second axial grooves 146, which are grooves recessed from the outer peripheral surface toward the second inside, are formed over the entire area in the second axial direction on the outer periphery of the cylindrical portion 141 and the protruding portion 143. One or more second axial grooves 146 are formed in the circumferential direction. Furthermore, second radial grooves 147, which are grooves recessed from the end face toward the first side, are formed over the entire area in the second radial direction on the second end of the protruding portion 143. The second radial grooves 147 are formed at a position corresponding to the second axial grooves 146, and discharge the oil that has passed through the circulation holes 145 into the reservoir chamber R.

[0033] ((compartment member 150)) The partitioning member 150 is an annular member. The outer diameter of the partitioning member 150 is equal to or smaller than the inner diameter of the protruding portion 143 of the orifice plate 140, and is disposed on the second inner side of the protruding portion 143. The inner diameter of the partitioning member 150 is larger than the diameter of the first cylindrical portion 121 of the valve body 120 and smaller than the diameter of the second cylindrical portion 122.

[0034] ((Connection flow path portion 160)) The connection flow path section 160 has a cylindrical section 161 and a flange 162 that protrudes outward from the outer circumferential surface of the cylindrical section 161 at the second end on the second side along the entire circumference. The outer diameter of the cylindrical portion 161 is smaller than the diameter of the outer cylinder opening 12H of the outer cylinder 12, and the cylindrical portion 161 is fitted into the second inner side of the outer cylinder opening 12H. The inner diameter of the cylindrical portion 161 is larger than the diameter of the communication hole 145 of the orifice plate 140.

[0035] For example, the outer diameter of the flange 162 is the same as the outer diameter of the orifice plate 140. A notch 163 is formed by cutting out a portion of the circumferential direction on the outer periphery of the flange 162. The notch 163 is formed at a position corresponding to the second axial groove 146 of the orifice plate 140, and discharges the oil that has passed through the second axial groove 146 into the reservoir chamber R.

[0036] ((Housing 170)) The housing 170 has a cylindrical portion 171, a circular annular portion 172 protruding from the inner surface of the cylindrical portion 171 toward the second inside, and a cylindrical protruding portion 174 protruding from the inner surface of the first side end face 173 of the cylindrical portion 171 toward the first side.

[0037] A recess 176 recessed from the inner peripheral surface is formed around the entire circumference at the second end of the cylindrical portion 171. Furthermore, a recess 177 recessed from the outer peripheral surface is formed around the entire circumference at a location of the cylindrical portion 171 that is second outer than the annular portion 172. The inner diameter of the annular portion 172 is larger than the outer diameter of the protruding portion 115 of the first fixing member 111, and the first fixing member 111 is disposed on the second inner side of the annular portion 172.

[0038] The inner diameter of the protruding portion 174 is the same as the inner diameter of the cylindrical portion 171, and the outer diameter of the protruding portion 174 is smaller than the outer diameter of the cylindrical portion 171. With the orifice plate 140 and the connection flow path portion 160 arranged on the second inner side of the cylindrical portion 171 and the protruding portion 174 on the first side of the annular portion 172, a roll process is performed on the end portion on the first side of the protruding portion 174, thereby forming a bent portion 178. The orifice plate 140 and the connection flow path portion 160 are held by the annular portion 172 and the bent portion 178 so as not to move in the second axial direction. The outer diameter of the protruding portion 174 is smaller than the diameter of the case opening 13H (see FIG. 1) of the damper case 13, and the protruding portion 174 is fitted into the second inner side of the case opening 13H.

[0039] ((Ring 180)) The cross-sectional shape of ring 180 when cut along a plane parallel to the second axial direction is a rectangle with the second axial direction as the short side direction and the second radial direction as the long side direction. Also, the cross-sectional shape of ring 180 when cut along a plane perpendicular to the second axial direction is C-shaped. However, the shape of ring 180 is not particularly limited. For example, ring 180 may be a metal member. The ring 180 is fitted into the recess 135 of the covering portion 132 of the coil unit 130 and the recess 176 of the housing 170 .

[0040] FIG. 4 is a diagram showing an example of the pressure operation chamber 190 and the flow path. In the solenoid valve 100, a pressure operation chamber 190 is formed in a space surrounded by the recess 144 of the orifice plate 140, the partition member 150, the first fixing member 111, the second fixing member 112, the valve element 120, the coil unit 130, and the annular portion 172 of the housing 170. The diameter of the first cylindrical portion 121 of the valve element 120 is slightly smaller than the inner diameter of the partition member 150, and the first cylindrical portion 121 is disposed on the second inner side of the partition member 150. Therefore, the partition member 150 defines the pressure operation chamber 190 together with the first cylindrical portion 121 of the valve element 120. Hereinafter, the space within the pressure operation chamber 190 surrounded by the recess 144 of the orifice plate 140, the partition member 150, and the first cylindrical portion 121 and conical portion 123 of the valve element 120 will be referred to as a "third oil chamber Y3." Furthermore, the space within the pressure operation chamber 190 excluding the third oil chamber Y3 will be referred to as the "fourth oil chamber Y4."

[0041] Furthermore, in the solenoid valve 100, a first flow path R1 is formed through which oil in the communication path L flows to the third oil chamber Y3 through the second inner side of the cylindrical portion 161 of the connecting flow path portion 160 and the communication hole 145 of the orifice plate 140. A second flow path R2 is formed through which oil in the third oil chamber Y3 flows to the fourth oil chamber Y4 through the oblique hole 125 formed in the valve body 120. A third flow path R3 is formed through which oil in the fourth oil chamber Y4 passes through the notch 116 of the first fixing member 111, the second radial groove 147, the second axial groove 146, and the notch 163 of the connecting flow path portion 160 and is discharged to the reservoir chamber R.

[0042] Furthermore, the valve element 120 of the solenoid valve 100 is disposed on the second inner side of the coil 131 and the fixed part 110. When the coil 131 is energized and a current flows through the coil 131, a magnetic field is generated, and the first fixed member 111 becomes the north pole and the second fixed member 112 becomes the south pole. As a result, as shown in FIG. 4, the valve element 120 is attracted to the first fixed member 111 against the pressure of the oil flowing through the flow hole 145 of the orifice plate 140, and the valve element 120 moves to the first side.

[0043] FIG. 5 is a diagram showing the relationship between the value of the current flowing through the coil 131 and the opening area S1 of the first flow path R1 and the opening area S2 of the second flow path R2. The opening area S1 of the first flow path R1 depends on the distance between the tip 124 of the conical portion 123 of the valve body 120 and the opening of the communication hole 145 of the orifice plate 140. When the valve body 120 moves to the first side, the distance between the conical portion 123 of the valve body 120 and the opening of the communication hole 145 of the orifice plate 140 decreases. Therefore, the opening area S1 of the first flow path R1 decreases as the value of the current flowing through the coil 131 increases.

[0044] The opening area S2 of the second flow path R2 depends on the position of the second opening 127 of the oblique hole 125 formed in the valve body 120 relative to the cylindrical portion 117 of the second fixed member 112. When no current is flowing through the coil 131, the second opening 127 of the oblique hole 125 formed in the valve body 120 is located closer to the second side than the first end face of the cylindrical portion 117 of the second fixed member 112. Therefore, the opening area S2 of the second flow path R2 is determined by the gap between the second columnar portion 122 of the valve body 120 and the cylindrical portion 117 of the second fixed member 112. When the valve element 120 moves toward the first side and the second opening 127 of the oblique hole 125 is positioned closer to the first side than the first-side end face of the cylindrical portion 117 of the second fixed member 112, the oil that has passed through the oblique hole 125 is more likely to flow into the fourth oil chamber Y4 without passing through the gap between the valve element 120 and the second fixed member 112. Therefore, the opening area S2 of the second flow path R2 increases as the value of the current flowing through the coil 131 increases.

[0045] When a vehicle equipped with the suspension system 1 is started, the value of the current flowing through the coil 131 is set to a value equal to or greater than a first value and equal to or less than a second value, which is a normal operating region shown in Fig. 5. On the other hand, in an abnormal state in which an abnormality such as a disconnection occurs in the coil 131, the value of the current flowing through the coil 131 is less than the first value, as shown in Fig. 5. In the normal operating region and in an abnormal state, as the value of the current flowing through the coil 131 increases, the opening area S1 of the first flow path R1 decreases and the opening area S2 of the second flow path R2 increases. An example can be given in which the opening area S1 and the opening area S2 are set to be the same when the value of the current flowing through the coil 131 is the first value, and the opening area S2 is set to be equal to or greater than the opening area S1 in the normal operating region and less than the opening area S1 in an abnormal state.

[0046] [Operation of shock absorber 2] First, the operation of the shock absorber 2 during the extension process will be described with reference to FIG. During the extension stroke, the rod 20 moves to the other side 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.

[0047] Furthermore, the oil flows into the damping force generator 50 through the communication path L and the outer cylinder opening 12H. Then, the oil flows into the reservoir chamber R through the first flow path R1, the second flow path R2, and the third flow path R3 in the damping force generator 50, as shown in FIG. Furthermore, the pressure in the first oil chamber Y1 becomes relatively lower than that 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.

[0048] Next, the operation of the shock absorber 2 during the compression stroke will be described with reference to FIG. During the compression stroke, the rod 20 moves relative to one side with respect to the cylinder 11. 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 this rod 20 flows out from the communication hole 11H to the communication passage L.

[0049] 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 the same as 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 oil flows in the damping force generator 50 is the same during both the compression stroke and the extension stroke. The generation of the damping force by the damping force generator 50 will be described in detail below.

[0050] (normal time) FIG. 4 is a diagram showing an example of the flow of oil under normal circumstances. First, the generation of a damping force during normal operation when the coil 131 is energized and a force acts on the valve body 120 will be described. The oil in the communication path L flows into the third oil chamber Y3 through the second inside of the cylindrical portion 161 of the connecting flow path portion 160 and the communication hole 145 of the orifice plate 140 (in other words, through the first flow path R1) against the force acting on the valve element 120 due to the current flowing through the coil 131. The oil in the third oil chamber Y3 flows into the fourth oil chamber Y4 through the oblique hole 125 formed in the valve element 120 (in other words, through the second flow path R2). The oil in the fourth oil chamber Y4 flows into the reservoir chamber R through the notch 116 of the first fixing member 111, the second radial groove 147, the second axial groove 146, and the notch 163 of the connecting flow path portion 160 (in other words, through the third flow path R3). As described above, in the normal operating range, the opening area S2 of the second flow path R2 is greater than or equal to the opening area S1 of the first flow path R1, and therefore the damping force is generated by the flow of oil being restricted by the gap between the flow hole 145 of the orifice plate 140 and the valve body 120.

[0051] (When abnormal) FIG. 6 is a diagram showing an example of oil flow in an abnormal state. Next, the generation of the damping force in an abnormal state in which the coil 131 is in a non-energized state and no force acts on the valve body 120 will be described. In the event of an abnormality, as in the normal state, the oil in the communication passage L flows into the reservoir chamber R through the communication hole 145 of the orifice plate 140 and the oblique hole 125 of the valve element 120. However, in the abnormal state, no current flows through the coil 131, and therefore no force acts to move the valve element 120 toward the first side. On the other hand, the valve element 120 receives a force in a direction moving it toward the second side from the oil flowing from the communication passage L to the third oil chamber Y3. Therefore, as described above, in the abnormal state, the opening area S2 of the second flow passage R2 is less than the opening area S1 of the first flow passage R1, and a damping force is generated by the flow of oil being restricted by the gap between the second columnar portion 122 of the valve element 120 and the cylindrical portion 117 of the second fixing member 112.

[0052] As described above, the solenoid valve 100 is a solenoid valve that can control the flow rate of oil, which is an example of a working fluid. For example, the solenoid valve 100 can control the distance of the valve element 120 from the orifice plate 140 by controlling the amount of current flowing through the coil 131, and can thereby control the amount of oil flowing into the pressure operation chamber 190 through the flow hole 145. The solenoid valve 100 is also a solenoid valve that can control the pressure of the oil in the pressure operation chamber 190 by controlling the amount of oil flowing into the pressure operation chamber 190. The solenoid valve 100 includes an orifice plate 140 (an example of a valve seat) in which is formed a flow hole 145 (an example of an inlet hole) through which the oil flows. The solenoid valve 100 also includes a fixed core assembly 137 that includes the coil 131 and forms the pressure operation chamber 190 between itself and the orifice plate 140. The solenoid valve 100 also includes a partition member 150 that partitions the pressure operation chamber 190 into a third oil chamber Y3 (an example of a first chamber) on the upstream side and a fourth oil chamber Y4 (an example of a second chamber) on the downstream side. The solenoid valve 100 also includes a valve element 120 that is displaced by energizing a coil 131 to be able to close and open the communication hole 145. The valve element 120 has an oblique hole 125 (an example of a communication flow path) that can communicate between the third oil chamber Y3 and the fourth oil chamber Y4 and that reduces the opening area S2 of the second opening 127 on the second side (an example of one end side) depending on the distance from the orifice plate 140.

[0053] In the solenoid valve 100, the valve body 120, which is displaced when current is applied to the coil 131, is capable of blocking the flow hole 145 and has the oblique hole 125, so the number of parts is fewer than in a configuration in which, for example, an object capable of blocking the flow hole 145 is provided separately from the actuator.

[0054] The solenoid valve 100 further includes a housing 170 that houses the orifice plate 140, the coil 131, the partition member 150, and the valve body 120. The fixed core assembly 137 further includes a second fixed member 112 (an example of a second fixed core) that is disposed on the opposite side of the orifice plate 140 (in other words, the second side) from the first fixed member 111 (an example of a first fixed core). The first fixed member 111 and the second fixed member 112, together with the coil 131, the valve body 120, and the housing 170, constitute the solenoid actuator 105. Because the fixed core assembly 137 includes the second fixed member 112, the solenoid valve 100 can be easily assembled.

[0055] The opening area S2 is determined by the relative positions of the valve body 120 and the second fixed member 112. This allows for increased damping force during an abnormality while reducing the number of parts compared to a configuration in which an object capable of blocking the flow hole 145 is provided separately from the actuator. Note that the diameter of the second cylindrical portion 122 of the valve body 120 and the inner diameter of the cylindrical portion 117 of the second fixed member 112 may be the same so that the gap between them is zero. This allows for increased damping force when the coil 131 is in a non-energized state.

[0056] The valve body 120 has a groove 122g formed on its outer peripheral surface that connects the fourth oil chamber Y4 to a space 195 formed between the fixed core assembly 137 and an end (second end) opposite to the end facing the orifice plate 140 (first end). This makes the pressure in the space 195 and the fourth oil chamber Y4 the same, thereby stabilizing the operation of the valve body 120.

[0057] [How to fix the solenoid valve 100] The first end surface 173 of the cylindrical portion 171 of the housing 170 of the solenoid valve 100 is disposed on the second inner side of the holding member 90 in a state in which it is in contact with a portion of the damper case 13 surrounding the case opening 13H. In other words, the solenoid valve 100 is disposed on the second inner side of the holding member 90 in a state in which it is subjected to a force from the damper case 13 in a direction away from the damper case 13. The shape of the contact surface of the damper case 13 with the solenoid valve 100 is not particularly limited. For example, in order to more reliably apply a force in the away direction to the solenoid valve 100 in a state before contact, part or all of the contact surface may be curved toward the solenoid valve 100 and function as a disc spring.

[0058] In a cross-sectional shape cut along a plane parallel to the second axis direction, the size of recess 91 of holding member 90 and recess 177 of housing 170 in the second axis direction is larger than the size of ring 95 in the second axis direction (in other words, the diameter of ring 95). Furthermore, the size of recess 91 of holding member 90 and recess 177 of housing 170 in the second radial direction is smaller than the size of ring 95 in the second radial direction (in other words, the diameter of ring 95). When solenoid valve 100 is assembled to holding member 90, housing 170 is inserted into the second inner side of holding member 90 in a state in which ring 95 is elastically deformed so as to contract in diameter and be completely embedded in recess 177 of housing 170. Thereafter, when ring 95 is inserted to a position corresponding to recess 91 formed in holding member 90, ring 95 expands in diameter, and the second outer portion of ring 95 fits into recess 91 of holding member 90. After the solenoid valve 100 is assembled to the holding member 90, the solenoid valve 100 is subjected to a force in a direction away from the damper case 13, and therefore a first-side portion of the ring 95 abuts against a first-side surface of the recess 177 of the housing 170. Also, a second-side portion of the ring 95 abuts against a second-side surface of the recess 91 of the holding member 90. Therefore, movement of the solenoid valve 100 in the second axial direction relative to the holding member 90 is suppressed. As a result, the solenoid valve 100 is suppressed from coming off the holding member 90 and falling off the cylinder portion 10. Also, noise caused by movement of the ring 95 within the recess 91 of the holding member 90 and the recess 177 of the housing 170 is suppressed.

[0059] As described above, the shock absorber 2 is formed in a cylindrical shape having a recess 91 (an example of a first groove) on its inner circumferential surface, and includes a holding member 90 rigidly coupled to the outer periphery of the cylinder portion 10. The shock absorber 2 also includes a solenoid valve 100 (an example of an exterior component) formed in a cylindrical shape having a recess 177 (an example of a second groove) on its outer circumferential surface that can face the recess 91, and at least a portion of which is exposed from the outer circumferential surface of the cylinder portion 10. The shock absorber 2 also includes a damper case 13 (an example of a spring member) that applies a force in a direction away from the cylinder portion 10, and a ring 95 (an example of a clasp member) that is arranged across both the recess 91 and the recess 177 while they face each other.

[0060] According to the shock absorber 2, it is possible to prevent the solenoid valve 100 from falling off the cylinder portion 10 without using screw tightening or crimping, for example, and therefore it is possible to achieve low cost.

[0061] In the shock absorber 2, the force applied to the solenoid valve 100 in the direction away from the cylinder portion 10 is applied by the cylinder portion 10. This makes it possible to prevent the solenoid valve 100 from falling off the cylinder portion 10 without using a dedicated part for applying a force in the direction away from the cylinder portion 10 to the solenoid valve 100, thereby achieving low costs.

[0062] In the shock absorber 2, the cylinder portion 10 has a case opening 13H (an example of a through hole) that is smaller than the inner dimension of the holding member 90 (in other words, the inner diameter of the holding member 90) at a position facing the holding member 90. A portion of the solenoid valve 100 (for example, the connection flow path portion 160) is inserted into the case opening 13H, and a force in a direction away from the cylinder portion 10 is applied by the area between the case opening 13H and the holding member 90. This makes it possible to apply a large force to the solenoid valve 100 with a small surface pressure, compared to a configuration in which a force in a direction away from the cylinder portion 10 is applied to the flange 162 of the connection flow path portion 160 of the solenoid valve 100. As a result, it is possible to achieve movement of the solenoid valve 100 in the second axial direction relative to the holding member 90 with a simple configuration.

[0063] Second Embodiment FIG. 7 is a diagram showing an example of a cross section of a solenoid valve 200 according to the second embodiment. The solenoid valve 200 according to the second embodiment differs from the solenoid valve 100 according to the first embodiment in that it has a second fixed member 212 that corresponds to the second fixed member 112. The solenoid valve 200 also differs from the solenoid valve 100 in that it has a guide member 290 that is fitted into the second inner side of the second fixed member 212 and guides movement of the valve element 120 in the second axial direction. The differences from the first embodiment will be described below. The same components in the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

[0064] Guide member 290 is molded using a non-magnetic material such as resin, and has a cylindrical tube portion 291, a bottom portion 292 that covers the opening on the second side of tube portion 291, and an annular portion 293 that protrudes from the end portion on the first side of tube portion 291 to the second outside.

[0065] The inner diameter of the tubular portion 291 is larger than the diameter of the second columnar portion 122 of the valve body 120, similar to the inner diameter of the second fixed member 112 according to the first embodiment. The size of the tubular portion 291 in the second axial direction is equal to or larger than the size of the second fixed member 112 according to the first embodiment. In addition, the position of the end portion on the first side of the tubular portion 291 is the same as the position of the end portion on the first side of the second fixed member 112 according to the first embodiment.

[0066] The bottom portion 292 covers a portion of the covering portion 132 of the coil unit 130 that is second inner than the second fixing member 212 . The annular portion 293 covers a part of the surface of the covering portion 132 of the coil unit 130 on the fourth oil chamber Y4 side. The guide member 290 configured as above is disposed so that the inner peripheral surface of the cylindrical portion 291 comes into contact with the outer peripheral surface of the valve body 120, and guides the movement of the valve body 120 in the second axial direction.

[0067] The second fixing member 212 according to the second embodiment differs from the second fixing member 112 according to the first embodiment in that a cylindrical portion 217 corresponding to the cylindrical portion 117 is different. The cylindrical portion 217 according to the second embodiment has an inner diameter and an outer diameter that are larger than the inner diameter and outer diameter of the cylindrical portion 117 according to the first embodiment. Furthermore, the position of the end portion on the first side of the cylindrical portion 217 is located on the second side of the position of the end portion on the first side of the cylindrical portion 117. The second fixing member 212 is disposed on the second outer side of the tubular portion 291 of the guide member 290.

[0068] As described above, the solenoid valve 200 includes the cylindrical portion 291 and the bottom portion 292, and has the guide member 290 that houses the valve element 120 so that the valve element 120 is displaceable on the inner circumferential surface of the cylindrical portion 291, and isolates the coil 131 and the second fixed member 212 from the fourth oil chamber Y4. The solenoid valve 200 has the guide member 290, which improves the slidability of the valve element 120.

[0069] In the solenoid valve 200, the opening area S2 is determined by the relative positions of the valve element 120 and the guide member 290. This increases the damping force in the event of an abnormality. Note that the diameter of the second cylindrical portion 122 and the inner diameter of the cylindrical portion 291 may be the same so that the gap between the second cylindrical portion 122 of the valve element 120 and the cylindrical portion 291 of the guide member 290 becomes zero. This increases the damping force when the coil 131 is in a non-energized state.

[0070] Furthermore, a groove 122g formed on the outer peripheral surface of the valve body 120 communicates with the fourth oil chamber Y4 a space 195 formed between an end portion (in other words, a second-side end portion) opposite to an end portion (in other words, a first-side end portion) facing the orifice plate 140 and a bottom portion 292 of the guide member 290. This makes the pressure in the space 195 and the fourth oil chamber Y4 the same, thereby stabilizing the operation of the valve body 120.

[0071] The coil unit 130, the second fixed member 212, and the guide member 290 may constitute a fixed core assembly 237 that includes the coil 131 and forms the pressure operation chamber 190 between itself and the orifice plate 140. By configuring the fixed core assembly 237 to include the guide member 290, it becomes possible to assemble the fixed core assembly 237 to the housing 170, which makes it easier to assemble the solenoid valve 200.

[0072] <Third embodiment> FIG. 8 is a diagram showing an example of a cross section of a solenoid valve 300 according to the third embodiment. The solenoid valve 300 according to the third embodiment differs from the solenoid valve 200 according to the second embodiment in that it has a guide member 390 corresponding to the guide member 290 and an orifice plate 340 corresponding to the orifice plate 140. The differences from the second embodiment will be described below. The same components in the second and third embodiments are designated by the same reference numerals, and detailed descriptions thereof will be omitted.

[0073] The guide member 390 according to the third embodiment differs from the guide member 290 according to the second embodiment in that it covers the entire portion of the coil unit 130 on the fourth oil chamber Y4 side. More specifically, in addition to the tubular portion 291, the bottom portion 292 and the annular portion 293, the guide member 390 has a second tubular portion 394 that cylindrically protrudes from the second outer end of the annular portion 293 to the first side, and a second annular portion 395 that is annular and protrudes from the first end of the second tubular portion 394 to the second outer side. The second annular portion 395 is disposed on the first side of the annular portion 172 of the housing 170 and is sandwiched between the annular portion 172 and the orifice plate 340 . The second cylindrical portion 394 covers the surface of the coil unit 130 on the fourth oil chamber Y4 side and the second inner end of the annular portion 172 of the housing 170.

[0074] In the orifice plate 340 according to the third embodiment, the size of the protruding portion 143 in the second axial direction is smaller than that of the orifice plate 140 according to the second embodiment. The protruding portion 143 sandwiches the second annular portion 395 of the guide member 390 between itself and the annular portion 172 of the housing 170.

[0075] As described above, the solenoid valve 300 includes the cylindrical portion 291 and the bottom portion 292, and houses the valve element 120 on the inner circumferential surface of the cylindrical portion 291 so that the valve element 120 is displaceable. The solenoid valve 300 also includes the guide member 390, which isolates the coil 131 and the second fixed member 212 from the fourth oil chamber Y4. The solenoid valve 300 includes the guide member 390, which improves the slidability of the valve element 120.

[0076] The solenoid valve 100 according to the first embodiment, the solenoid valve 200 according to the second embodiment, and the solenoid valve 300 according to the third embodiment are solenoid valves that can control the flow rate of oil in only one flow path (first flow path R1, second flow path R2, and third flow path R3) in the damping force generator 50 that is provided outside the cylinder portion 10. The solenoid valve 100 according to the first embodiment, the solenoid valve 200 according to the second embodiment, and the solenoid valve 300 according to the third embodiment may also be used to control the flow rate of oil in a flow path that adjusts the back pressure in a direction that closes a main valve that is arranged on the main flow path, as in the damping force generator described in Patent Document 1.

[0077] <Fourth embodiment> FIG. 9 is a diagram showing an example of a cross section of a shock absorber 402 according to the fourth embodiment. A shock absorber 402 according to the fourth embodiment differs from the shock absorber 2 according to the first embodiment in the manner in which a force is applied to the solenoid valve 100 in a direction away from the cylinder portion 10. The following describes the differences from the first embodiment. The same reference numerals are used for the same components in the first and fourth embodiments, and detailed descriptions thereof will be omitted.

[0078] In the damper case 413 of the fourth embodiment, the diameter of the case opening 413H, which corresponds to the case opening 13H of the first embodiment, is larger than the inner diameter of the cylindrical portion 171 of the housing 170, and the first side end face 173 of the cylindrical portion 171 does not come into contact with the damper case 413.

[0079] The shock absorber 402 has a coil spring 415 provided between the periphery of the outer cylinder opening 12H of the outer cylinder 12 and the flange 162 of the connection flow path portion 160 of the solenoid valve 100. The coil spring 415 is disposed around the cylindrical portion 161 of the connection flow path portion 160 so that the center line direction is the second axial direction. The coil spring 415 is in a compressed state when the solenoid valve 100 is assembled to the cylinder portion 10. Therefore, the solenoid valve 100 is disposed on the second inner side of the holding member 90 while receiving a force from the coil spring 415 in a direction away from the cylinder portion 10.

[0080] As described above, the cylinder portion 10 has an outer cylinder body opening 12H (an example of a through hole) that is smaller than the inner dimension of the holding member 90 (in other words, the inner diameter of the holding member 90) at a position facing the holding member 90. In the shock absorber 402, a portion of the solenoid valve 100 (for example, the first side end of the cylindrical portion 161 of the connection flow path portion 160) is inserted into the outer cylinder body opening 12H, and a force in a direction away from the cylinder portion 10 is applied by the region between the outer cylinder body opening 12H and the holding member 90. In addition, a force in a direction away from the cylinder portion 10 is applied by the coil spring 415. As a result, the force in the direction away from the cylinder portion 10 is applied to the solenoid valve 100 with high reliability, and therefore, movement of the solenoid valve 100 in the second axial direction relative to the holding member 90 is suppressed with high reliability.

[0081] In the first to fourth embodiments described above, the solenoid valve 100 that electronically adjusts the damping force is exemplified as an exterior component at least a portion of which is exposed from the outer circumferential surface of the cylinder portion 10. However, the exterior component is not limited to the solenoid valve 100. The exterior component may be a component that mechanically adjusts the flow rate of oil to adjust the damping force, such as the adjustment section of the outer damping section of the third embodiment described in Japanese Patent No. 6997348. [Explanation of symbols]

[0082] 1...suspension device, 2,402...shock absorber, 10...cylinder portion, 11...cylinder, 12...outer cylinder, 12H...outer cylinder opening (an example of a through hole), 13,413...damper case (an example of a spring member), 13H, 413H...case opening (an example of a through hole), 20...rod, 30...piston portion, 50...damping force generating device, 90...retaining member, 91...recess (an example of a first groove), 95...ring (an example of a clasp member), 100, 200, 300...solenoid valve (an example of an exterior part), 105...solenoid actuator, 110...fixing portion, 111...first fixing member, 112...second fixing member, 122g...groove, 120...valve body, 125...oblique hole ( an example of a communicating flow passage), 126...first opening, 127...second opening (an example of an opening), 130...coil unit, 131...coil, 137...stationary core assembly, 140...orifice plate (an example of a valve seat), 145...flow hole (an example of an inlet hole), 150...partition member, 160...connecting flow passage portion, 161...cylindrical portion, 162...flange, 170...housing, 177...recess (an example of a second groove), 190...pressure operation chamber, 195...space, 415...coil spring, R1...first flow passage, R2...second flow passage, R3...third flow passage, S1, S2...opening area, Y3...third oil chamber (an example of a first chamber), Y4...fourth oil chamber (an example of a second chamber)

Claims

1. a holding member formed in a cylindrical shape having a first groove on an inner peripheral surface thereof and rigidly coupled to an outer periphery of the cylinder portion; an exterior part formed in a cylindrical shape having a second groove on an outer circumferential surface thereof capable of opposing the first groove, at least a portion of which is exposed from the outer circumferential surface of the cylinder part; a spring member that applies a force in a direction away from the cylinder portion; a clasp member disposed across the first groove and the second groove in a state where the first groove and the second groove face each other; A shock absorber having:

2. The force applied to the exterior part in a direction away from the cylinder part is applied by the cylinder part. The shock absorber according to claim 1 .

3. the cylinder portion has a through hole at a position facing the holding member and smaller in size than the inner dimension of the holding member; a portion of the exterior component is inserted into the through-hole, and a force in a direction away from the cylinder portion is applied to the exterior component by a region between the through-hole of the cylinder portion and the holding member; The shock absorber according to claim 2 .

4. The exterior part is a solenoid valve that can adjust the characteristics of the shock absorber. The shock absorber according to claim 1 .

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