JP2014009760A - Damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a damper in which cost of a damping force generation mechanism can be reduced.SOLUTION: A damping force generation mechanism 30 comprises: a disc valve 55 or 90 in a disc shape for generating a damping force; an annular main or pilot body 46 or 49 (seating member) where the disc valve 55 or 90 is seated/unseated: a pilot pin 47 (fastening member) inserted through the disc valve and the annular main or pilot body to fasten them; oil liquid flow passages 65, 66, and 67 provided by opening 66A at an axial end portion of the pilot pin 47 and extending axially; a seat part 72 provided around the opening 66A; a pilot valve member 102 (valve element) seated/unseated in the seat part 72; and an actuator operating the pilot valve member 102. Thus, cost relating to components and assembly can be reduced.

Description

  The present invention relates to a shock absorber that generates a damping force by controlling a flow of a working fluid with respect to a stroke of a piston rod.

  A shock absorber mounted on a suspension device of a vehicle such as an automobile generally has a piston in which a piston rod is connected in a cylinder filled with a working fluid so that the piston rod can slide. Thus, the flow of fluid generated by the sliding of the piston in the cylinder is controlled by a damping force generation mechanism including an orifice, a disk valve and the like to generate a damping force.

  For example, in the damping force adjustment type shock absorber described in Patent Document 1, a back pressure chamber is formed at the back of a main disk valve that is a damping force generating mechanism, and a part of the flow of the working fluid is introduced into the back pressure chamber. The valve opening of the main disk valve is controlled by applying the internal pressure of the back pressure chamber to the main disk valve in the valve closing direction and adjusting the internal pressure of the back pressure chamber by the solenoid valve.

JP 2011-75060 A

  Like the one described in Patent Document 1, a shock absorber provided with a main disk valve, a back pressure chamber, a solenoid valve, etc. as a damping force generation mechanism has a complicated structure and a large number of parts. The shape is also complicated, and as a result, the number of assembly steps has been greatly increased to ensure assembly accuracy and sealing performance, which in turn has been a factor in increasing costs.

  It is an object of the present invention to provide a shock absorber that can reduce the cost of a damping force generation mechanism.

  In order to solve the above-described problems, a shock absorber according to the present invention includes a cylinder in which a working fluid is sealed, a piston that is slidably fitted in the cylinder, and an outside of the cylinder connected to the piston. And a damping force generation mechanism that generates a damping force by controlling the flow of the working fluid generated by sliding of the piston, and the damping force generation mechanism is a circle that generates the damping force. A plate-shaped disc valve, an annular seating member on which the disc valve is separated and seated, a fastening member for inserting and fastening the disc valve and the seating member, and an axial end portion of the fastening member being opened And a seat portion provided around the opening, a valve body that is separated from and seated on the seat portion, and an actuator that operates the valve body. Material contrast, the fastening member by caulking, characterized in that integrating the said seating member and said disc valve.

  According to the shock absorber according to the present invention, it is possible to reduce the cost of the damping force generation mechanism.

It is sectional drawing of the buffer which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view which expands and shows the damping force generation mechanism of FIG. FIG. 3 is an enlarged view of a main part of FIG. 2. It is an expanded sectional view which shows the action | operation of a damping force generation mechanism. It is a figure which shows embodiment which concerns on the assembly of a valve block, (a) shows 1st Embodiment, (b) shows 2nd Embodiment.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, a damping force adjustment type shock absorber 1 that is a shock absorber according to the present embodiment has a double cylinder structure in which an outer cylinder 3 is provided outside a cylinder 2. A reservoir 4 is formed between the two. A piston 5 is slidably fitted in the cylinder 2, and the inside of the cylinder 2 is defined by the piston 5 as two chambers, a cylinder upper chamber 2A and a cylinder lower chamber 2B. One end of a piston rod 6 is connected to the piston 5 by a nut 7. The other end side of the piston rod 6 passes through the cylinder upper chamber 2A, is inserted into the rod guide 8 and the oil seal 9 mounted on the upper ends of the cylinder 2 and the outer cylinder 3, and extends to the outside of the cylinder 2. Yes. A base valve 10 that partitions the cylinder lower chamber 2 </ b> B and the reservoir 4 is provided at the lower end of the cylinder 2.

  The piston 5 is provided with passages 11 and 12 for communicating between the cylinder upper chamber 2A and the cylinder lower chamber 2B. The passage 12 is provided with a check valve 13 that allows only the working fluid to flow from the cylinder lower chamber 2B side to the cylinder upper chamber 2A side. Further, the passage 11 is provided with a disk valve 14 which opens when the pressure of the working fluid on the cylinder upper chamber 2A side reaches a predetermined pressure and relieves it to the cylinder lower chamber 2B side.

  The base valve 10 is provided with passages 15 and 16 that allow the cylinder lower chamber 2B and the reservoir 4 to communicate with each other. The passage 15 is provided with a check valve 17 that allows only working fluid to flow from the reservoir 4 side to the cylinder lower chamber 2B side. The passage 16 is provided with a disk valve 18 that opens when the pressure of the working fluid on the cylinder lower chamber 2B side reaches a predetermined pressure and relieves it to the reservoir 4 side. As the working fluid, an oil liquid is sealed in the cylinder 2, and an oil liquid and a gas are sealed in the reservoir 4.

  A separator tube 20 is externally fitted to the cylinder 2 via seal members 19 at both upper and lower ends, and an annular passage 21 is formed between the cylinder 2 and the separator tube 20. The annular passage 21 is communicated with the cylinder upper chamber 2 </ b> A by a passage 22 provided in a side wall near the upper end portion of the cylinder 2. A cylindrical connection port 23 is formed in the lower part of the separator tube 20 so as to protrude sideways and open. An opening 24 that is concentric with the connection port 23 and larger in diameter than the connection port 23 is provided on the side wall of the outer cylinder 3, and a cylindrical case 31 is joined by welding or the like so as to surround the opening 24. . A damping force generating mechanism 30 is attached to the case 31.

Next, the damping force generation mechanism 30 will be described mainly with reference to FIGS. Hereinafter, for the sake of convenience of explanation, in the attenuation generation mechanism 30 shown in FIG. 2, the cylinder 2 side (left side) will be described as one end side and the solenoid block 37 side will be described as the other end side.
As shown in FIGS. 2 and 3, the damping force generating mechanism 30 includes a pilot block (back pressure type) main valve 32 and a valve block 35 in which a fail valve 33 that operates at the time of failure is integrated into a unit. It comprises a solenoid block 37 that operates a pilot valve 36 that is a solenoid-driven pressure control valve for controlling the valve opening pressure of the valve 32. Then, the passage member 40 is inserted into the cylindrical case 31, the valve block 35 and the solenoid block 37 are coupled and integrated, and these are inserted into the case 31, and the nut 38 is screwed into the case 31. Fixed by.

  A plurality of cutouts 31 </ b> B for communicating the inside of the reservoir 4 and the liquid chamber 45 in the case 31 are formed in the inner flange 31 </ b> A formed at one end of the case 31. The main body 46 (described later) of the valve block 35 and the connection port 23 of the separator tube 20 communicate with each other through a passage member 40. The passage member 40 includes a cylindrical portion 41 having a communication passage 43 and a flange portion 42 that extends in the radial direction from the outer periphery of the other end portion of the cylindrical portion 41. The inner peripheral surface and outer peripheral surface of the cylindrical portion 41 of the passage member 40 and the one end surface and the other end surface on the inner peripheral side of the flange portion 42 are covered with a seal member 44. The flange portion 42 of the passage member 40 is in close contact with the main body 46 and is in contact with the inner flange 31A of the case 31, and the cylindrical portion 41 penetrates the one end opening 31C of the case 31 and the tip thereof is the connection port 23. Inserted into. As a result, the connection member 23 communicates with the inside of the main body 46 by the passage member 40, and the joint portion between the connection port 23 and the main body 46 is sealed by the seal member 44.

The valve block 35 includes the main valve 32, a main body 46 that is a seating member for the main valve 32, a fail valve 33, a pilot pin 47 that is a fastening member, and a pilot body that is a seating member for the fail valve 33 and the pilot valve 36. 49.
The main body 46 is formed in an annular shape having a support hole 48 for supporting a pilot pin penetrating in the axial direction at the center in the radial direction. A plurality of passages 50 penetrating in the axial direction are provided in the main body 46 along the circumferential direction. A circular recess 51 is formed at one end of the main body 46. The flange portion 42 of the passage member 40 comes into contact with the surface around the circular recess 51 of the main body 46. Each passage 50 is formed outside the circular recess 51. Each passage 50 of the main body 46 communicates with the communication passage 43 of the passage member 40 via the circular recess 51. At one end of the support hole 48 facing the circular recess 51, a large-diameter recess 52 that supports the one end side projection 70A (or the caulking portion 70B) of the pilot pin 47 is formed.

  A main disc valve 55 constituting the main valve 32 is disposed at the other end of the main body 46. The main disc valve 55 adjusts the bending rigidity of the main valve 32 and the disc 55A with the sliding seal member in which the sliding seal member 57 is fixed to the outer peripheral portion on the back side in order from the back side (solenoid block 37 side). A plurality of discs 55B, and a disc 55C with slits in which a plurality of slits 56 serving as orifices for setting the damping force in the low speed region of the piston speed are circumferentially spaced apart from each other. It is configured. The sliding seal member 57 provided on the outer peripheral portion on the back side of the disk 55A with the sliding seal member is fixed by a method such as baking. Further, at the other end of the main body 46, an annular seat 58 projecting toward the main valve 32 on the outer peripheral side of each passage 50, and projecting toward the main valve 32 on the inner peripheral side of each passage 50. An annular clamp portion 59 is formed. The outer peripheral portion of the disc with slit 55C of the main disc valve 55 is seated on the seat portion 58 of the main body 46, and the inner peripheral portion of the disc with slit 55C is brought into contact with the clamp portion 59. On the other hand, a disk-shaped retainer 53 and a washer 54 are arranged in this order on the inner peripheral portion of the disk 55A with a sliding seal member of the main disk valve 55. The washer 54 has a larger diameter than the retainer 53. Further, a cylindrical collar 60 is disposed on the other end portion side of the washer 54 so as to contact the other end surface of the washer 54. The collar 60 is formed with a small-diameter opening 61 that contacts the outer peripheral surface of the pilot pin 47 on one end side and a large-diameter opening 62 that extends continuously from the small-diameter opening 61 to the other end side. An annular gap 63 is formed between the inner peripheral surface of the large diameter opening 62 and the outer peripheral surface of the pilot pin 47. The outer diameter of the collar 60 is formed larger than the outer diameter of the washer 54.

  The pilot pin 47 is formed in a cylindrical shape. The pilot pin 47 has a large-diameter flow passage 65 that opens at one end and extends in the axial direction, a small-diameter flow passage 66 that has a smaller diameter than the large-diameter flow passage 65, and that opens at the other end 66A and extends in the axial direction. An orifice passage 67 that connects the radial flow passage 65 and the small-diameter flow passage 66 is formed. A communication hole 68 extending in the radial direction is opened on the inner peripheral surface on one end side of the small-diameter flow passage 66. A plurality of communication holes 68 are formed radially. Each communication hole 68 is opened to face the annular gap 63, and communicates the small-diameter flow passage 66 and the annular gap 63. At the other end portion of the pilot pin 47, an annular seat portion 72 projects in the axial direction around the opening 66A of the small-diameter flow passage 66.

  A caulking structure is adopted when assembling the valve block 35 and will be described later in detail with reference to FIG. 4. However, when the other end side of the pilot pin 47 is caulked, One end side protruding portion 70A is provided which protrudes radially outward from the outer periphery of one end portion, and a caulking portion 71B is formed which caulks the other end portion of pilot pin 47 and protrudes radially outward during caulking. (Corresponding to FIG. 5A). Further, when caulking one end portion side of the pilot pin 47, the other end side projecting portion 71A projecting radially outward from the outer periphery of the other end portion of the pilot pin 47 is already provided. One end portion of 47 is caulked to form a caulking portion 70B projecting radially outward (corresponding to FIG. 5B).

  A passage forming disk 73 is disposed on the other end side of the collar 60. The passage forming disk 73 is formed by laminating a notched disk 73A and a disk 73B. The notched disk 73A is in contact with the other end surface of the collar 60, that is, the surface having the annular gap 63 inside. An elongated notch 74 extending in the radial direction is formed on the inner peripheral edge of the notched disk 73A. A back pressure chamber 78 (to be described later) and a small-diameter flow passage 66 of the pilot pin 47 communicate with each other through the notch 74, the annular gap 63, and the communication holes 68.

  A pilot cover 75 is disposed on the other end side of the passage forming disk 73. The pilot cover 75 is formed in a U-shaped cross section including a disc-shaped portion 76 having an insertion hole 86 for inserting a pilot pin and a cylindrical body 77 extending from the outer peripheral end of the disc-shaped portion 76 to one end side. Is done. The disc-shaped portion 76 of the pilot cover 75 is brought into contact with the disc 73B of the passage forming disc 73. Further, the outer peripheral portion of the sliding seal member 57 of the disc 55A with the sliding seal member is slidably and fluid-tightly attached to the inner peripheral surface of the cylindrical body portion 77 of the pilot cover 75. As a result, a back pressure chamber 78 is formed in a range surrounded by the sliding seal member 57 and the pilot cover 75. Thus, by adopting the pilot cover 75 to configure the back pressure chamber 78, it is possible to contribute to cost reduction. That is, conventionally, since a cylindrical wall portion for forming the back pressure chamber 78 is provided in the pilot body, processing such as cutting is required. However, since the pilot cover 75 has a simple shape, press processing or the like is required. Since it can be manufactured at low cost, it can contribute to overall cost reduction.

  The pilot body 49 is formed in a substantially bottomed cylindrical shape including a bottom portion 80 provided on one end side and a cylindrical wall portion 81 extending from the outer peripheral portion of the bottom portion 80 to the other end side. The other end opening of the pilot body 49 is closed by a holding plate 82. As a result, the valve chamber 100 is formed between the cylindrical wall portion 81 of the pilot body 49 and the holding plate 82. A support hole 83 for supporting the pilot pin 47 is formed in the axial direction at the radial center of the bottom 80 of the pilot body 49. The bottom portion 80 is provided with a plurality of passages 84 extending in the axial direction around the support hole 83 along the circumferential direction. Each passage 84 communicates with the valve chamber 100. Each passage 84 is open between a sheet portion 91 and a clamp portion 92 described later. At the other end of the support hole 83, a large-diameter recess 85 that supports the other end side projection 71 </ b> A (or the caulking portion 71 </ b> B) of the pilot pin 47 is formed inside each passage 84. The cylindrical wall portion 81 of the pilot body 49 has an inner diameter that increases stepwise toward the opening side, and two step portions 114 and 115 are formed on the inner peripheral portion. A fail disk valve 90, a retainer 93, and a washer 94 that constitute the fail valve 33 are disposed between the bottom 80 of the pilot body 49 and the disc-like portion 76 of the pilot cover 75. In the fail disc valve 90, a plurality of slits 95, which are orifices for setting damping force in the low speed region of the piston speed, are formed in order from the back side (solenoid block 37 side) at circumferential intervals in the outer peripheral edge. The disc 90A with slits and a plurality of discs 90B for adjusting the bending rigidity of the fail disc valve 90 are laminated. At one end portion of the pilot body 49, an annular seat portion 91 projecting toward the fail valve 33 on the outer peripheral side of each passage 84 and an annular seat projecting toward the fail valve 33 on the inner peripheral side of each passage 84 The clamp portion 92 is formed. The outer peripheral portion of the slit disc 90A of the fail disc valve 90 is seated on the seat portion 91 of the pilot body 49, and the inner peripheral portion of the slit disc 90A is brought into contact with the clamp portion 92. On the other hand, a disc-shaped retainer 93 and a washer 94 are arranged in this order on the inner periphery of the disk 90B of the fail disk valve 90. The disc-like portion 76 of the pilot cover 75 comes into contact with the washer 94. The washer 94 is formed with a larger diameter than the retainer 93.

  In the valve chamber 100 formed between the cylindrical wall portion 81 of the pilot body 49 and the holding plate 82, the pilot pin 47 is separated from and seated on an annular seat portion 72 provided at the other end of the pilot pin 47. A pilot valve member 102 which is a constituent valve body of the pilot valve 36 for opening and closing the small-diameter flow passage 66 is provided. The pilot valve member 102 is formed in a substantially cylindrical shape having a through hole 111 and a receiving hole 105. One end face of the pilot valve member 102 is formed with a valve front end portion 103 that extends in an annular shape with a substantially triangular cross section and is seated on and away from the seat portion 72 of the pilot pin 47. A flange-shaped spring receiving portion 104 extending in the radial direction is formed on the outer peripheral portion on the other end side of the pilot valve member 102. An accommodation hole 105 for accommodating one end of the operating rod 106 is formed in the pilot valve member 102. A rod receiving portion 110 that supports the operating rod 106 is formed at one end of the pilot valve member 102. A through hole 111 is formed in the center portion in the radial direction of the rod receiving portion 110. The other end opening edge of the accommodation hole 105 of the pilot valve member 102 is expanded in a tapered shape. The spring receiving portion 104 serves as a pressure receiving surface with respect to the valve chamber 100 in a state where the back surface (the other end surface) is in contact with the holding plate 82, and therefore, the force when moving the spring receiving portion 104 against the pressure of the valve chamber 100 is reduced. Therefore, it is desirable to make the diameter as small as possible while securing the diameter necessary to contact the pilot spring 112 described later.

  The pilot valve member 102 is elastically held by a pilot spring 112 and a fail spring 113 so as to face the seat portion 72 and move in the axial direction. A radially outer peripheral end portion (end portion of each spring portion 121) of the pilot spring 112 is supported by the step portion 114 of the cylindrical wall portion 81 of the pilot body 49. Further, a fail spring 113 and a holding plate 82 are overlapped on the step portion 115 of the cylindrical wall portion 81 and fixed by a cap 116 fitted to the other end opening of the cylindrical wall portion 81.

More specifically, the fail spring 113 includes a large-diameter portion 117 that abuts on the step portion 115 and a small-diameter portion 118 that is disposed concentrically with the large-diameter portion 117 and that abuts on the spring receiving portion 104 when the pilot valve member 102 is inserted. The large-diameter portion 117 and the small-diameter portion 118 are elastically displaced in the axial direction to apply a biasing force to the movement in the axial direction. On the other hand, the pilot spring 112 includes an annular contact portion 120 that is in contact with one end surface of the spring receiving portion 104 of the pilot valve member 102 and a spring portion 121 that extends radially from the outer peripheral portion of the contact portion 120. Is done. The pilot spring 112 is arranged such that the abutting portion 120 abuts against the spring receiving portion 104 and the tip end portion of each spring portion 121 abuts against the stepped portion 114 of the cylindrical wall portion 81.
The holding plate 82 is provided with a through hole 101 for accommodating the other end portion of the pilot valve member 102 in the center portion in the radial direction and for communicating the valve chamber 100 with the liquid chamber 45 in the case 31. The inner diameter of the through hole 101 is formed larger than the outer diameter of the pilot valve member 102. The holding plate 82 abuts on the spring receiving portion 104 of the pilot valve member 102 and regulates its retracted position.

  The cap 116 includes a disc portion 125 that has an insertion hole 127 that supports the operating rod 106 and fixes the holding plate 82, and a cylindrical body portion 126 that extends from the outer peripheral edge of the disc portion 125 to one end side. It is formed in a bottomed cylindrical shape. The cylindrical body 126 includes a small-diameter body 129 and a large-diameter body 130 that are alternately formed along the circumferential direction. A notch 141 extending to the periphery of 130 is formed. The cap 116 has an inner peripheral surface of the small-diameter barrel portion 129 fitted into an outer peripheral surface of the cylindrical wall portion 81 of the pilot body 49, and an outer peripheral surface of the large-diameter barrel portion 130 is inside the cylindrical portion 158 of the solenoid case 145 described later. It is fitted to the peripheral surface. In this fitted state, the valve chamber 100 and the liquid chamber 45 in the case 31 are communicated with each other by the notches 141 of the cap 116.

  The solenoid block 37 includes a coil 146 in the solenoid case 145, cores 147 and 148 inserted in the coil 146, a plunger 149 supported between the cores 147 and 148 so as to be movable in the axial direction, and a plunger 149. A hollow actuating rod 106 connected is integrated and integrated. These are fixed by an annular spacer 150 and a cup-shaped cover 151 attached to the other end of the solenoid case 145 by caulking. The coil 146, the cores 147 and 148, the plunger 149 and the operating rod 106 constitute a solenoid actuator. Then, by energizing the coil 146 through a lead wire (not shown), an axial thrust is generated in the plunger 149 according to the current. One end of the operating rod 106 has a tapered shape with a tapered outer periphery. The small diameter flow passage 66 of the pilot pin 47, the valve chamber 100, and the chamber 153 at the back of the operation rod 106 are communicated with each other by a communication passage 152 formed in the hollow operation rod 106. The plunger 149 is also provided with a communication passage 157 that allows the chambers 155 and 156 formed at both ends thereof to communicate with each other. These communication passages 152 and 157 balance the fluid force acting on the actuating rod 106 and the plunger 149, and provide an appropriate damping force for these movements.

The solenoid case 145 has a cylindrical portion 158 fitted into the case 31 on one end side, and the large-diameter trunk portion 130 of the cap 116 attached to the pilot body 49 is fitted into the cylindrical portion 158. A space between the cylindrical portion 158 and the case 31 is sealed with an O-ring 159. The solenoid case 145 has a rod receiving portion inserted into the receiving hole 105 of the pilot valve member 102 incorporated in the cylindrical wall portion 81 of the pilot body 49 with one end portion of the operating rod 106 protruding into the cylindrical portion 158. The large-diameter trunk portion 130 of the cap 116 attached to the pilot body 49 is engaged with the valve body 35 in a state where the large-diameter barrel portion 130 is fitted in the cylindrical portion 158. The solenoid case 145 is fixed to the case 31 by holding the retaining ring 160 attached to the outer peripheral groove with the nut 38. A spacer 161 is disposed between the disc portion 125 of the cap 116 and the core 147.
Note that the pilot body 49 and the main body 46 described above need only have strength as a pressure vessel and a seating member, and are preferably processed by forging or sintering in consideration of productivity. The pilot pin 47 is preferably formed by cold forging using carbon steel for mechanical structure such as S10C material, etc., in order to obtain productivity and strength. Further, the strength of the pilot pin 47 is smaller than that of the pilot valve member 102, but needs to be a strength that is approximate. That is, when the pilot valve member 102 is smaller than the strength of the seat portion 72 of the pilot pin 47, the valve tip portion 103 of the pilot valve member 102 and the seat portion 72 repeatedly come into contact with each other, so that the valve tip portion 103 is worn. This is to prevent the damping force characteristic from changing due to leakage. On the other hand, since the pilot pin 47 needs to caulk the caulking portion 71B, it needs to be strong enough to be caulked.

Next, a first embodiment relating to the assembly of the valve block 35 will be described with reference to FIG.
First, the valve block 35 is temporarily assembled on a support base (not shown).
That is, with the pilot pin 47 inserted into the support hole 48 from the other end side of the main body 46 and the one end side projection 70A of the pilot pin 47 engaged with the large-diameter recess 52 of the main body 46, 46 is set on the support so that the other end side having the annular seat portion 58 and the clamp portion 59 faces upward. Subsequently, the main disk valve 55 is inserted into the pilot pin 47 in the order of the disk with slit 55C, each disk 55B, and the disk with sliding seal member 55A, and stacked. Subsequently, the retainer 53 and the washer 54 are inserted and stacked on the pilot pin 47 in this order, and the small-diameter opening 61 and the large-diameter opening 62 of the collar 60 are inserted in the direction in which the small-diameter opening 61 faces the washer 54. . Subsequently, the passage forming disc 73 is inserted into the pilot pin 47 in the order of the notched disc 73A and the disc 73B, and the insertion hole 86 of the pilot cover 75 is positioned on the main body 46 side of the cylindrical body 77. Insert like so. As a result, the outer peripheral portion of the sliding seal member 57 of the disc 55A with the sliding seal member comes into fluid-tight contact with the inner peripheral surface of the cylindrical body 77 of the pilot cover 75 in a slidable manner. Subsequently, the washer 94 and the retainer 93 are inserted into the pilot pin 47 in this order, and the fail disk valve 90 is inserted and stacked in the order of each disk 90B and the slit disk 90A. Finally, the support hole 83 of the pilot body 49 is inserted into the pilot pin 47 from the one end side provided with the annular seat portion 91 and the clamp portion 92 of the pilot body 49.

Next, the shaft portion 181 of the jig 180 is inserted into the large-diameter flow passage 65 of the pilot pin 47. The shaft portion 181 of the jig 180 is driven in the vertical direction. Subsequently, the stepped portion 115 of the cylindrical wall portion 81 of the pilot body 49 is pressed with a predetermined pressing force by the valve presser 182. At the same time, the shaft portion 181 of the jig 180 presses the inside of the large-diameter flow passage 65 toward the pilot body 49 with a predetermined pressing force. As a result, a load in the tensile direction is applied to the pilot pin 47. Then, by applying a pressing force from the valve presser 182 and a pressing force from the shaft portion 181 of the jig 180, the outer peripheral portion of the other end portion of the pilot pin 47 is crimped by the punch 183 so as to be expanded. A caulking portion 71B is formed, and the caulking portion 71B is accommodated in a large-diameter recess 85 provided in the pilot body 49. As a result, the assembly of the valve block 35 is completed.
As described above, in the first embodiment, in order to form the orifice passage 67 of the pilot pin 47, the jig 180 is used by utilizing a portion connected from the large-diameter flow passage to the small-diameter orifice passage 67 on the inner peripheral side of the pilot pin 47. Since the shaft portion 181 can be pressed, no additional work on the pilot pin 47 for caulking is required.

Next, 2nd Embodiment which concerns on the assembly of the valve block 35 is described based on FIG.5 (b).
First, the valve block 35 is temporarily assembled on a support base (not shown).
That is, the pilot pin 47 is inserted into the support hole 83 of the pilot body 49 from the other end side, and the other end side protrusion 71A of the pilot pin 47 is engaged with the large-diameter recess 85 of the pilot body 49. The body 49 is set on the support so that the one end side having the annular seat portion 91 and the clamp portion 92 faces upward. Subsequently, the fail disc valve 90 is inserted into the pilot pin 47 in the order of the disc 90A with slit and each disc 90B and stacked. Subsequently, the retainer 93 and the washer 94 are inserted and stacked in this order on the pilot pin 47, and then the insertion hole 86 of the pilot cover 75 is positioned so that the cylindrical body 77 is located on the opposite side of the pilot body 49 side. Insert into. Subsequently, the passage forming disk 73 is inserted into the pilot pin 47 in the order of the disk 73B and the notched disk 73A and stacked, and the large diameter opening 62 and the small diameter opening 61 of the collar 60 are combined with the large diameter opening 62. Is inserted in a direction facing the notched disc 73A. Subsequently, the washer 54 and the retainer 53 are inserted and stacked on the pilot pin 47 in this order, and then the main disk valve 55 is arranged in the order of the disk 55A with the sliding seal member, each disk 55B, and the disk 55C with the slit. Insert and stack with. Finally, the support hole 48 of the main body 46 is inserted into the pilot pin 47 from the other end side provided with the annular seat portion 58 and the clamp portion 59 of the main body 46.

  Next, the end surface of the cylindrical body 185 of the jig 180 is brought into contact with the other end surface (lower surface) of the other end side projection 71 </ b> A of the pilot pin 47. The cylindrical body 185 of the jig 180 is driven in the vertical direction. Subsequently, the outer periphery of the one end surface (upper surface) of the main body 46 is pressed with a predetermined pressing force by the valve presser 182. At the same time, the cylindrical body 185 of the jig 180 is pressed toward the main body 46 with a predetermined pressing force. As a result, a load in the compression direction is applied to the component member between the main body 46 and the pilot body 49. The caulking portion is formed by caulking the peripheral wall of one end portion of the pilot pin 47 with the punch 183 while applying the pressing force from the valve presser 182 and the pressing force from the cylindrical body 185 of the jig 180. 70B is formed, and the caulking portion 70B is accommodated in the large-diameter recess 52 provided in the main body 46. As a result, the assembly of the valve block 35 is completed.

  Thus, since the valve block 35 can be integrated by the caulking structure of the pilot pin 47, the shape of the pilot body 49 and the like can be simplified as compared with the prior art, and the number of assembly steps can be reduced. it can.

Next, the operation of the damping force adjusting shock absorber 1 will be described.
The damping force adjusting type shock absorber 1 is mounted between the sprung springs of the suspension device of the vehicle, a lead wire (not shown) is connected to an in-vehicle controller or the like, and in a normal operation state in the damping force generating mechanism 30, FIG. 4, the coil 146 is energized and the pilot valve member 102 is connected to the pilot pin 47 by the actuating rod 106 as shown in the lower half (when the sign is viewed upright, below the center line of the actuating rod 106). The spring part 121 of the pilot spring 112 is brought into contact with the step part 114 of the cylindrical wall part 81 of the pilot body 49 by advancing toward the seat part 72 of the pilot body 49, and resists the spring force of the fail spring 113 and the pilot spring 112. Then, the pilot valve member 102 is advanced, and the valve tip portion 103 is seated on the seat portion 72 of the pilot pin 47. Thereby, the valve opening pressure of the pilot valve 36 is controlled by the energization current to the coil 146, and the pressure control by the pilot valve 36 is executed.

  During the extension stroke of the piston rod 6, the check valve 13 of the piston 5 is closed by the movement of the piston 5 in the cylinder 2, and before the disc valve 14 is opened, the oil liquid on the cylinder upper chamber 2 </ b> A side is added. The pressure is passed through the passage 22 and the annular passage 21 and flows into the passage member 40 of the damping force generation mechanism 30 from the connection port 23 of the separator tube 20.

  At this time, the oil corresponding to the movement of the piston 5 opens the check valve 17 of the base valve 10 from the reservoir 4 and flows into the cylinder lower chamber 2B. When the pressure in the cylinder upper chamber 2A reaches the valve opening pressure of the disk valve 14 of the piston 5, the disk valve 14 is opened, and the pressure in the cylinder upper chamber 2A is relieved to the cylinder lower chamber 2B. Prevent excessive pressure rise of 2A.

  In the damping force generating mechanism 30, the oil liquid flowing in from the passage member 40 passes through the orifice passage 67 of the pilot pin 47 before the main disk valve 55 of the main valve 32 is opened (piston speed low speed region). The pilot valve member 102 of the pilot valve 36 is pushed open and flows into the valve chamber 100. Then, the oil in the valve chamber 100 flows from the through hole 101 of the holding plate 82 to the reservoir 4 through the notch 141 of the cap 116, the liquid chamber 45 in the case 31, and the notch 31B of the inner flange 31A. Therefore, when the piston speed is increased and the pressure on the cylinder upper chamber 2A side of the cylinder 2 reaches the valve opening pressure of the main disk valve 55, the oil that has flowed into the passage member 40 becomes the circular recess 51 and the main body 46. The main disc valve 55 is pushed open through each passage 50 and flows directly to the liquid chamber 45 in the case 31.

  On the other hand, during the contraction stroke of the piston rod 6, the check valve 13 of the piston 5 is opened by the movement of the piston 5 in the cylinder 2, the check valve 17 of the passage 15 of the base valve 10 is closed, and the disk valve 18 is opened. Before the valve, the fluid in the piston lower chamber 2B flows into the cylinder upper chamber 2A, and the amount of fluid that has entered the cylinder 2 from the piston rod 6 passes from the cylinder upper chamber 2A in the same path as in the above extension stroke. Through the reservoir 4. When the pressure in the cylinder lower chamber 2B reaches the valve opening pressure of the disk valve 18 of the base valve 10, the disk valve 18 is opened, and the pressure in the cylinder lower chamber 2B is relieved to the reservoir 4, thereby Prevent excessive pressure rise of 2B.

  Thus, during the expansion / contraction stroke of the piston rod 6, in the damping force generating mechanism 30, before the main disk valve 55 of the main valve 32 is opened (piston speed low speed region), the orifice passage 67 of the pilot pin 47 and the pilot A damping force is generated by the valve opening pressure of the pilot valve member 102 of the valve 36. Further, after the main disk valve 55 is opened (piston speed high speed region), a damping force is generated according to the opening degree of the main disk valve 55. The damping force can be directly controlled regardless of the piston speed by adjusting the valve opening pressure of the pilot valve 36 by the energization current to the coil 146. At this time, due to the valve opening pressure of the pilot valve 36, the internal pressure of the back pressure chamber 78 changes to the small-diameter flow passage 66 of the pilot pin 47 via each communication hole 68, the annular gap 63, and the notch 74 of the notched disk 73A. Since the internal pressure of the back pressure chamber 78 acts in the valve closing direction of the main disk valve 55, the valve opening pressure of the main disk valve 55 can be adjusted simultaneously by controlling the valve opening pressure of the pilot valve 36. Thereby, the adjustment range of the damping force characteristic can be widened.

  Further, when the energization current to the coil 146 is reduced and the thrust of the plunger 149 is reduced, the valve opening pressure of the pilot valve 36 is reduced, a soft-side damping force is generated, the energization current is increased, and the plunger is increased. When the thrust of 149 is increased, the valve opening pressure of the pilot valve 36 increases and a hard-side damping force is generated. Therefore, a soft-side damping force that is generally used frequently can be generated at a low current. , Power consumption can be reduced.

  If the thrust of the plunger 149 is lost due to the failure of the coil 146, the failure of the on-vehicle controller, etc., the upper half in FIG. As shown on the upper side of the center line), the pilot valve member 102 is retracted by the spring force of the fail spring 113, the back surface of the spring receiving portion 104 is brought into contact with the holding plate 82, the through hole 101 is closed, and the pilot pin 47 is closed. Is opened. At this time, since the spring portion 121 of the pilot spring 112 is separated from the step portion 114 of the cylindrical wall portion 81 of the pilot body 49, no spring force is generated. In this state of the pilot valve member 102, the oil in the valve chamber 100 flows through the passages 84 of the pilot body 49, pushes the fail disc valve 90 open, and flows into the liquid chamber 45 in the case 31. As described above, the flow of the oil liquid from the valve chamber 100 to the liquid chamber 45 in the case 31 is controlled by the fail disk valve 90, so that a desired attenuation is set by setting the valve opening pressure of the fail disk valve 90. In addition to generating a force, the internal pressure of the back pressure chamber 78, that is, the valve opening pressure of the main disk valve 55 can be adjusted. As a result, an appropriate damping force can be obtained even during a failure.

  In the present embodiment described above, the part related to the pressure control by the pilot valve 36 is configured such that the pilot pin 47 is provided with the orifice passage 67 and the pilot pin 47 is provided with the seat portion 72 at the other end. Since the pilot pin 47 is integrated into one part, the shape of the pilot body 49 can be simplified as compared with the prior art, and the pilot body 49 can be changed from a full cutting process to an inexpensive machining method such as sintering. This can contribute to cost reduction. Further, since the seat portion 72 is formed at the other end portion of the pilot pin 47, the strength and durability of the seat portion 72 can be improved. In addition, the degree of freedom and ease of tuning and design change are improved.

In the present embodiment, the valve block 35 includes a main disk valve 55 that is the main valve 32, a pilot cover 75, a fail disk valve 90 that is the fail valve 33, and the like between the main body 46 and the pilot body 49. Since the pilot pin 47 is integrated with the caulking structure, the number of assembling steps can be reduced and the overall cost can be reduced.
Moreover, according to the first and second embodiments relating to the assembly of the valve block 35, the axial force of the pilot pin 47 can be easily controlled, and the secular change of the damping force due to the aging of the axial force is suppressed. can do.

  In the present embodiment, the case where the present invention is applied to a double cylinder type shock absorber having the reservoir 4 is described. However, the present invention is not limited to this, and a damping force generation mechanism similar to that of the present embodiment is used. If it has, you may apply to the damping force generation | occurrence | production of the single cylinder type buffer which formed the gas chamber in the cylinder with the free piston. Further, the working fluid is not limited to the oil liquid, and other liquids such as water may be used. Alternatively, only a gas such as air or nitrogen gas may be used without using a liquid. In this case, the reservoir 4, the base valve 10, the free piston, and the like are not necessary.

  In the above embodiment, a pilot-controlled shock absorber is shown, the valve body is the pilot valve member 102 that controls the pilot pressure, and the valve block 35 is configured by the pilot body 49. However, the present invention is not limited to this, but can be applied to a shock absorber that adjusts the damping force by controlling the flow of the working fluid in the cylinder by directly opening and closing the valve body with a solenoid instead of the pilot pressure.

  1 Damping force adjustable shock absorber (buffer), 2 cylinder, 3 outer cylinder, 4 reservoir, 5 piston, 6 piston rod, 30 damping force generating mechanism, 32 main valve, 33 fail valve, 35 valve block, 37 solenoid block 46 Main body (seat member), 47 Pilot pin (fastening member), 49 Pilot body (seat member), 55 Main disk valve, 65 Large diameter flow path, 66 Small diameter flow path, 66A opening, 67 Orifice path, 90 Fail disk Valve, 102 Pilot valve member (valve element), 106 Actuating rod (actuator), 146 Coil (actuator), 147, 148 Core (actuator), 149 Plunger (actuator)

Claims (2)

A cylinder filled with a working fluid, a piston slidably fitted in the cylinder, a piston rod connected to the piston and extending to the outside of the cylinder, and an operation caused by sliding of the piston A damping force generation mechanism that generates a damping force by controlling the flow of fluid,
The damping force generation mechanism is
A disc-shaped disc valve that generates damping force;
An annular seating member on which the disc valve is seated;
A fastening member for inserting and fastening the disk valve and the seating member;
A working fluid flow passage provided in an axially open end of the fastening member and extending in the axial direction;
A sheet portion provided around the opening;
A valve body seated on and off the seat portion;
An actuator for operating the valve body;
Including
The shock absorber characterized in that the disk valve and the seating member are integrated by caulking the fastening member against the seating member.   The shock absorber according to claim 1, wherein the valve body is configured to have greater strength than the fastening member.

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