WO2016052142A1 - Cylinder apparatus - Google Patents

Abstract

　A cylinder apparatus (10) has: a cylinder (11) in which a working fluid is sealed; a piston (25) which is slidably fitted inside the cylinder (11), the piston (25) dividing a first chamber (28) and a second chamber (29); a piston rod (31) linked to the piston (25); an outer tube (13) provided to the outer periphery of the cylinder (11), the outer tube (13) forming a reservoir chamber (12) in which the working fluid and a working gas are sealed between the outer tube (13) and the cylinder (11); and a base member (20) provided to a first end part of the cylinder (11), the base member (20) dividing the second chamber (29) and the reservoir chamber (12) inside the cylinder (11), the outer tube (13) being provided with a protrusion (91) formed by elastic deformation, the protrusion (91) protruding in an annular shape toward the cylinder (11).

Description

Cylinder device

The present invention relates to a cylinder device.
This application claims priority based on the Japan patent application 2014-199615 for which it applied on September 30, 2014, and uses the content here.

There is a cylinder device in which a separate member is provided between the cylinder and the outer cylinder outside the cylinder (for example, see Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 48-99575 Japanese Unexamined Patent Publication No. 2005-188601

If a separate member is provided between the cylinder and the outer cylinder, the number of parts increases and the cost increases.

Therefore, the present invention provides a cylinder device that can reduce the number of parts and suppress an increase in cost.

According to the first aspect of the present invention, a cylinder device includes a cylinder in which a working liquid is sealed, a cylinder device slidably fitted in the cylinder, and a first chamber and a second chamber defined in the cylinder. A piston, a piston rod connected to the piston, an outer cylinder that is provided on the outer peripheral side of the cylinder and forms a reservoir chamber in which a working liquid and a working gas are enclosed, and the cylinder. A base member that is provided at a first end and defines the second chamber and the reservoir chamber in the cylinder, and the outer cylinder is formed by plastic deformation and is annular toward the cylinder It is characterized in that a projecting portion is provided to project.

According to the second aspect of the present invention, the projecting portion may have a plurality of cuts in the circumferential direction.

According to the third aspect of the present invention, a plurality of the projecting portions may be provided in the axial direction.

According to the fourth aspect of the present invention, the projecting portion may be inclined.

According to the fifth aspect of the present invention, the cylinder device includes a cylinder in which the working liquid is sealed, a slidably fitted in the cylinder, and a first chamber and a second chamber defined in the cylinder. A piston, a piston rod connected to the piston, an outer cylinder that is provided on the outer peripheral side of the cylinder and forms a reservoir chamber in which a working liquid and a working gas are enclosed, and the cylinder. A base member that is provided at a first end portion and that defines the second chamber and the reservoir chamber in the cylinder, and the outer cylinder is plastically deformed toward the cylinder. A plurality of projecting portions projecting from each other are provided by shifting the positions in the axial direction and the circumferential direction.

According to the above cylinder device, the number of parts can be reduced and the cost increase can be suppressed.

It is a longitudinal section showing the cylinder device concerning a 1st embodiment of the present invention. FIG. 2 is a cross-sectional view of the cylinder device according to the first embodiment of the present invention, taken along X1-X1 in FIG. It is a longitudinal cross-sectional view which shows the cylinder apparatus which concerns on 2nd Embodiment of this invention. FIG. 4 is a cross-sectional view taken along the line X2-X2 of FIG. 3 showing a cylinder device according to a second embodiment of the present invention. It is a longitudinal cross-sectional view which shows the cylinder apparatus which concerns on 3rd Embodiment of this invention. It is a partial front view which shows the cylinder apparatus which concerns on 3rd Embodiment of this invention. FIG. 9 is a cross-sectional view taken along the line X3-X3 of FIG. 6 illustrating a cylinder device according to a third embodiment of the present invention. It is a longitudinal cross-sectional view which shows the cylinder apparatus which concerns on 4th Embodiment of this invention. It is a longitudinal cross-sectional view which shows the cylinder apparatus which concerns on 5th Embodiment of this invention. It is a partial front view which shows the cylinder apparatus which concerns on 5th Embodiment of this invention. It is a longitudinal section showing a cylinder device concerning a 6th embodiment of the present invention. FIG. 12 is a cross-sectional view taken along the line X4-X4 of FIG. 11 showing a cylinder device according to a sixth embodiment of the present invention.

“First Embodiment”
A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

A cylinder device 10 according to the first embodiment shown in FIG. 1 is a shock absorber used for a suspension device of a vehicle such as an automobile or a railway vehicle. The cylinder device 10 includes a cylindrical cylinder 11 in which a working liquid is sealed, and a bottomed cylindrical outer cylinder 13 that is larger in diameter than the cylinder 11 and provided on the outer peripheral side of the cylinder 11. The reservoir chamber 12 is formed between the cylinder 11 and the outer cylinder 13. The reservoir chamber 12 is filled with working liquid and working gas. That is, the cylinder device 10 has a double cylinder structure.

The outer cylinder 13 includes a metal main body member 14 formed of a substantially cylindrical member, and a bottomed cylindrical metal that fits inside the one end opening of the main body member 14 and closes the opening. And a closing member 15 made of metal. The cylindrical portion 16 and the main body member 14 that are fitted to the main body member 14 of the closing member 15 constitute a cylindrical portion 17 of the outer cylinder 13. The bottom portion 18 of the closing member 15 that does not fit into the main body member 14 also forms the bottom portion 18 of the outer cylinder 13. The closing member 15 is fixed to the main body member 14 by welding so that the outer cylinder 13 is in a sealed state. The outer cylinder 13 is provided coaxially with the cylinder 11 and covers the cylinder 11 on the outer side in the radial direction of the cylinder 11. Although only a part is shown in FIG. 1, an annular mounting eye 19 is fixed to the outside of the closing member 15.

The cylinder 11 is composed of one member having a metal cylindrical shape. The cylinder 11 is engaged with the bottom 18 of the outer cylinder 13, that is, the closing member 15 through the base member 20. The base member 20 has an annular shape. The base member 20 is attached to the first end portion of the cylinder 11 in the axial direction. Further, the cylinder 11 is engaged via the rod guide 21 on the side opposite to the bottom 18 of the cylindrical portion 17 of the outer cylinder 13, that is, on the side opposite to the closing member 15 of the main body member 14. The rod guide 21 has an annular shape. The rod guide 21 is attached to the second end of the cylinder 11 in the axial direction.

The base member 20 is fitted and attached to the cylinder 11. A portion of the base member 20 opposite to the axial cylinder 11 is placed on the bottom 18 of the outer cylinder 13, that is, the closing member 15. The base member 20 is disposed coaxially with the outer cylinder 13 by fitting into the bottom portion 18, that is, the annular step portion 22 of the closing member 15. Thereby, the first end portion in the axial direction of the cylinder 11 is arranged coaxially with the outer cylinder 13.

The rod guide 21 is fitted to the cylinder 11 and attached. The rod guide 21 is fitted to the inner peripheral portion on the opposite side of the bottom portion 18 of the cylindrical portion 17 of the outer cylinder 13, that is, on the opposite side of the main body member 14 from the closing member 15. Thereby, the second end portion in the axial direction of the cylinder 11 is arranged coaxially with the outer cylinder 13. An annular seal member 23 is disposed on the opposite side of the rod guide 21 from the closing member 15. The seal member 23 is also fitted to the inner peripheral portion of the main body member 14.

In the cylinder 11, a piston 25 is slidably fitted. The piston 25 defines a first chamber 28 and a second chamber 29 in the cylinder 11. The first chamber 28 is provided on the opposite side of the bottom 18 from the piston 25 in the cylinder 11. The second chamber 29 is provided closer to the bottom 18 than the piston 25 in the cylinder 11. The second chamber 29 in the cylinder 11 is defined as the reservoir chamber 12 by the base member 20 provided at the first end of the cylinder 11.

The piston rod 31 is connected to the piston 25. The piston rod 31 is inserted into the cylinder 11 through the seal member 23 and the rod guide 21. The piston 25 is connected to the distal end portion of the piston rod 31 on the insertion side. The piston 25 is fastened to the piston rod 31 by a nut 33. The piston 25 moves integrally with the piston rod 31. The piston rod 31 extends from the cylinder 11 and the outer cylinder 13 to the outside through the rod guide 21 and the seal member 23. In the cylinder device 10, for example, the piston rod 31 is connected to the vehicle body of the vehicle, and the mounting eye 19 is connected to the wheel of the vehicle to generate a damping force with respect to the movement of the wheel relative to the vehicle body.

The rod guide 21 has a piston rod 31 slidably inserted inside the rod guide 21. The seal member 23 has a piston rod 31 slidably inserted inside the seal member 23. The piston rod 31 is arranged on the central axis of the cylinder 11 by a piston 25 arranged in the cylinder 11 at a first end portion arranged in the cylinder 11. The intermediate portion of the piston rod 31 in the axial direction is arranged on the central axis of the cylinder 11 by the rod guide 21 fitted to the cylinder 11 and the outer cylinder 13. That is, the piston rod 31 is supported coaxially with the cylinder 11 by the piston 25 and the rod guide 21.

The rod guide 21 supports the piston rod 31 so as to be movable in the axial direction while restricting the radial movement of the piston rod 31. The outer peripheral portion of the seal member 23 is fitted so as to be in close contact with the inner side of the outer cylinder 13 of the cylinder 11. The piston rod 31 is inserted into the inner peripheral portion of the seal member 23 so as to be in a close contact state. As a result, the seal member 23 closes the first end of the cylinder 11. The seal member 23 restricts the working liquid in the cylinder 11 and the working gas and working liquid in the reservoir chamber 12 from leaking to the outside. An engaging portion 35 is formed on the opposite side of the main body member 14 from the closing member 15 by bending the main body member 14 radially inward. A portion of the seal member 23 opposite to the piston rod 31 in the axial direction is locked by a locking portion 35.

A passage 42 and a passage 43 penetrating in the axial direction are formed in an intermediate portion of the base member 20 in the radial direction. A passage 42 is disposed on the inner side in the radial direction of the base member 20. A passage 43 is arranged outside the passage 42 in the radial direction of the base member 20. The passages 42 and 43 are configured to allow communication between the second chamber 29 and the reservoir chamber 12. A disk valve 45 is disposed on the bottom 18 side of the base member 20. The disc valve 45 has an annular shape. The disc valve 45 can close the passage 42 by contacting the base member 20. A disc valve 46 is disposed on the side opposite to the bottom 18 of the base member 20. The disk valve 46 has an annular shape. The disk valve 46 can close the passage 43 by contacting the base member 20.

The disk valves 45 and 46 are attached to the base member 20 by rivets 48 and rings 49 and 50. The rivet 48 includes a shaft portion 51 and a flange portion 52 having a larger diameter than the shaft portion 51. In the rivet 48, the shaft portion 51 is inserted in this order inside the disc valve 45, the base member 20, the disc valve 46, the ring 50 and the ring 49 in this order, and the outer portion of the shaft portion 51 than the ring 49 is It is crimped so as to spread outward in the radial direction. The caulking portion 53 and the flange portion 52 of the rivet 48 formed by the caulking clamp the disc valve 45, the base member 20, the disc valve 46, and the rings 49, 50 from both sides in the axial direction.

The disc valve 45 has a larger diameter than the flange portion 52. The disc valve 45 opens the passage 42 by being deformed so that the outer portion of the disc valve 45 is separated from the base member 20. The disk valve 46 has a larger diameter than the ring 50. The disk valve 46 is deformed so that the outer portion of the disk valve 50 is separated from the base member 20, thereby opening the passage 43.

The disc valve 45 allows the flow of the working liquid from the second chamber 29 to the reservoir chamber 12 through a passage hole (not shown) formed in the disc valve 46 and the passage 42. The disk valve 45 is a damping valve that generates a damping force by controlling the flow of the working liquid. The disc valve 45 regulates the flow of the working liquid from the reservoir chamber 12 to the second chamber 29 via the passage 42. In the disc valve 45, the piston rod 31 moves to the contraction side to increase the amount of entry into the cylinder 11, the piston 25 moves to the second chamber 29 side, and the pressure in the second chamber 29 is higher than the pressure in the reservoir chamber 12. When it becomes higher than the value, the passage 42 is opened. The disk valve 45 is a damping valve that generates a damping force at that time.

The disc valve 46 is a check valve that allows the flow of the working liquid from the reservoir chamber 12 to the second chamber 29 through the passage 43 and restricts the flow of the working liquid through the passage 43 in the opposite direction. When the piston rod 31 moves to the extending side to increase the amount of protrusion from the cylinder 11 and the piston 25 moves to the first chamber 28 side, the pressure in the second chamber 29 drops below the pressure in the reservoir chamber 12. Open 43. The disk valve 46 is a suction valve that allows the working liquid to flow from the reservoir chamber 12 into the second chamber 29 without substantially generating a damping force.

The piston rod 31 has a main shaft portion 55 having a constant diameter and an inner end shaft portion 56 on the end portion to be inserted into the cylinder 11. The inner end shaft portion 56 has a smaller diameter than the main shaft portion 55. A male screw 57 is formed on the opposite side of the inner shaft portion 56 from the main shaft portion 55.

The piston 25 has an annular shape. A passage 64 and a passage 65 penetrating in the axial direction are formed in an intermediate portion in the radial direction of the piston 25. A passage 64 is disposed outside in the radial direction of the piston 25. A passage 65 is disposed inside the passage 64 in the radial direction of the piston 25. The inner end shaft portion 56 of the piston rod 31 is inserted on the inner peripheral side of the piston 25. The passages 64 and 65 are configured to allow communication between the first chamber 28 and the second chamber 29.

In the piston 25, an annular disc valve 61 capable of closing the passage 64 by contacting the piston 25 is disposed on the side opposite to the bottom portion 18. In addition, a disk valve 62 is disposed on the bottom 18 side of the piston 25. The disk valve 62 has an annular shape. The disc valve 62 can close the passage 65 by contacting the piston 25.

The disk valves 61 and 62 are attached to the piston rod 31 together with the piston 25, a ring 67 having an annular shape, and a regulating member 68 having an annular shape. That is, the inner end shaft portion 56 of the piston rod 31 is inserted in this order on the inner peripheral side of each of the regulating member 68, the disk valve 61, the piston 25, the disk valve 62, and the ring 67. Then, the nut 33 is screwed onto the male screw 57 outside the ring 67 of the inner end shaft portion 56. Accordingly, the regulating member 68, the disc valve 61, the piston 25, the disc valve 62, and the ring 67 are sandwiched between the nut 33 and the end surface of the main shaft portion 55 on the inner end shaft portion 56 side and attached to the piston rod 31.

The disk valve 61 opens the passage 64 by being deformed so as to be separated from the piston 25 in the axial direction. The disk valve 62 is deformed so as to be separated from the piston 25 in the axial direction, thereby opening the passage 65.

The disc valve 61 allows the flow of the working liquid from the second chamber 29 to the first chamber 28 through the passage 64. On the other hand, the flow of the working liquid from the first chamber 28 to the second chamber 29 through the passage 64 is restricted. The disc valve 61 opens the passage 64 when the piston rod 31 moves to the contraction side and the piston 25 moves to the second chamber 29 side and the pressure in the second chamber 29 becomes higher than the pressure in the first chamber 28 by a predetermined value or more. . The disc valve 61 generates a damping force at that time. That is, the disc valve 61 is a contraction side damping valve.

The disc valve 62 allows the flow of the working liquid from the first chamber 28 to the second chamber 29 through the passage 65. On the other hand, the flow of the working liquid from the second chamber 29 to the first chamber 28 through the passage 65 is restricted. The disc valve 62 opens the passage 65 when the piston rod 31 moves to the extension side, the piston 25 moves to the first chamber 28 side, and the pressure in the first chamber 28 becomes higher than the pressure in the second chamber 29 by a predetermined value or more. . At that time, the disc valve 62 generates a damping force. That is, the disc valve 62 is an expansion-side damping valve.

Here, when the piston rod 31 moves to the extension side and the amount of protrusion from the cylinder 11 increases, the amount of working liquid corresponding to the amount of protrusion opens the disk valve 46 of the base member 20 from the reservoir chamber 12 and the passage 43. Through the second chamber 29. Conversely, when the piston rod 31 moves to the contraction side and the amount of insertion into the cylinder 11 increases, an amount of working liquid corresponding to the amount of insertion opens from the second chamber 29 to the reservoir via the passage 42 while opening the disc valve 45. It flows into the chamber 12.

The rod guide 21 includes a rod guide main body 70 and a collar 71. The rod guide body 70 includes a substantially stepped shape. The rod guide body 70 has an annular shape. The collar 71 has a cylindrical shape. The collar 71 is fitted and fixed to the inner peripheral portion of the rod guide main body 70. An annular large-diameter cylindrical portion 74 is formed at the first axial end portion of the rod guide body 70. A small-diameter cylindrical portion 75 is formed at the second axial end portion of the rod guide body 70. The outer diameter of the small diameter cylindrical portion 75 is smaller than the outer diameter of the large diameter cylindrical portion 74. The large diameter cylindrical portion 74 and the small diameter cylindrical portion 75 are formed coaxially. The large-diameter cylindrical portion 74 of the rod guide main body 70 is fitted to the cylindrical portion 17 of the outer cylinder 13, that is, the inner peripheral portion of the main body member 14. Further, the small diameter cylindrical portion 75 of the rod guide main body 70 is fitted to the inner peripheral portion of the cylinder 11.

In the rod guide main body 70, a communication hole 77 penetrating along the axial direction is formed in the intermediate portion in the radial direction of the large-diameter cylindrical portion 74. The communication hole 77 communicates with the reservoir chamber 12 between the outer cylinder 13 and the cylinder 11. The collar 71 is fitted and fixed to the inner peripheral surface of the rod guide main body 70. The main shaft portion 55 of the piston rod 31 is inserted into the collar 71 so as to be in sliding contact.

The annular check lip 78 extending to the rod guide 21 side is formed on the seal member 23. The check lip 78 is capable of sealing contact over the entire circumference with a predetermined tightening margin with respect to the rod guide 21. The hydraulic fluid leaking from the gap between the rod guide 21 and the piston rod 31 is accumulated in the chamber 80 on the gap side of the check lip 78. The check lip 78 opens when the pressure in the chamber 80 becomes a predetermined amount higher than the pressure in the reservoir chamber 12, and allows the working fluid accumulated in the chamber 80 to flow into the reservoir chamber 12 through the communication hole 77. That is, the check lip 78 functions as a check valve that allows the flow of the hydraulic fluid and the gas only in the direction from the chamber 80 to the reservoir chamber 12 and restricts the flow in the reverse direction.

In the first embodiment, the main body member 14 constituting the cylindrical portion 17 of the outer cylinder 13 is provided with a protruding portion 91. The projecting portion 91 projects annularly from the inner peripheral surface of the main body member 14 toward the cylinder 11. The main body member 14 includes a protruding portion 91, a cylindrical portion 92 on the opposite side of the protruding portion 91 from the closing member 15, a cylindrical portion 93 of the protruding portion 91 on the closing member 15 side, and a protruding portion of the cylindrical portion 93. It has a tapered cylindrical portion 94 opposite to the portion 91 and a cylindrical portion 95 opposite to the cylindrical portion 93 of the tapered cylindrical portion 94. The projecting portion 91, the cylindrical portion 92, the cylindrical portion 93, the tapered cylindrical portion 94, and the cylindrical portion 95 are formed coaxially with the central axes aligned. The protruding portion 91 is provided with a concave portion 96 that is recessed in an annular shape from the outer peripheral surface of the main body member 14 toward the cylinder 11 on the radially outer side.

The inner diameter of the cylindrical portion 92 is the same as the inner diameter of the cylindrical portion 93. The outer diameter of the cylindrical portion 92 is the same as the outer diameter of the cylindrical portion 93. The tapered cylindrical portion 94 extends from the end edge portion of the cylindrical portion 93 opposite to the cylindrical portion 92. The tapered cylindrical portion 94 has a conical cylindrical shape having a larger diameter on the side opposite to the cylindrical portion 92. The cylindrical portion 95 extends in an opposite direction to the cylindrical portion 93 from an end edge portion of the tapered cylindrical portion 94 opposite to the cylindrical portion 93. The cylindrical part 95 has a cylindrical shape. The inner diameter of the cylindrical portion 95 is larger than the inner diameter of the cylindrical portions 92 and 93. The outer diameter of the cylindrical portion 95 is larger than the outer diameter of the cylindrical portions 92 and 93.

The projecting portion 91 is continuously formed over the entire circumference of the main body member 14 as shown in FIG. The protruding portion 91 is formed at a fixed position in the axial direction of the main body member 14. As shown in FIG. 1, the projecting portion 91 includes a tapered cylindrical portion 101 on the cylindrical portion 92 side, a tapered cylindrical portion 102 on the cylindrical portion 93 side, and a cylindrical portion 103 between the tapered cylindrical portions 101 and 102. The

The tapered cylindrical portion 101 extends from the end portion of the cylindrical portion 92 on the cylindrical portion 93 side. The tapered cylindrical portion 101 has a conical cylindrical shape having a smaller diameter as it is farther from the cylindrical portion 92. The tapered cylindrical portion 102 extends from an end edge portion of the cylindrical portion 93 on the cylindrical portion 92 side. The tapered cylindrical portion 102 has a conical cylindrical shape having a smaller diameter as the distance from the cylindrical portion 93 increases. The cylindrical portion 103 connects the edge portions of the tapered cylindrical portions 101 and 102 on the side close to each other. The cylindrical portion 103 has a cylindrical shape. A concave portion 96 is also formed by the tapered cylindrical portions 101 and 102 and the cylindrical portion 103.

In the protruding portion 91, the inner diameter of the cylindrical portion 103 which is the minimum diameter portion of the protruding portion 91 is larger than the outer diameter of the cylinder 11. Between the projecting portion 91 and the cylinder 11 arranged coaxially, a radial gap is formed in an annular shape over the entire circumference. This gap has a smaller area (flow path area) on the plane orthogonal to the central axis of the cylinder 11 than the gap between the cylindrical portions 92 and 93 and the cylinder 11.

The main body member 14 is made of steel, for example. The main body member 14 is formed by plastically deforming a material made of a cylindrical body. Specifically, the protruding portion 91, the tapered tube portion 94, and the cylindrical portion 95 are formed by plastic deformation. On the other hand, the cylindrical part 92 and the cylindrical part 93 are in the state of the raw material before plastic deformation.

The projecting portion 91 is formed by pressurizing the material from the radially outer side toward the radially inner side and plastically deforming the material radially inward. The tapered cylindrical portion 94 and the cylindrical portion 95 are formed by pressurizing the material from the radially inner side to the radially outer side and plastically deforming the material radially outward. When the projecting portion 91 is formed by plastic deformation, for example, a disk-shaped processing roller having an outer peripheral portion whose cross section on the surface including the central axis has the same shape as the concave portion 96 is prepared. Is arranged in parallel with the center axis of the material, and the material and the processing roller are rotated synchronously while pressing the outer peripheral portion of the processing roller against the outer peripheral surface of the material, thereby reducing the distance between the axes of the material and the processing roller. Thereby, the protruding portion 91 including the concave portion 96 is formed to be continuous over the entire circumference.

The main body member 14 is fixed by fitting the cylindrical portion 16 of the closing member 15 to the cylindrical portion 95 having the largest diameter of the main body member 14. The entire protruding portion 91 is disposed on the opposite side of the base member 20 from the bottom portion 18 in the axial direction of the outer cylinder 13. Further, the entire projecting portion 91 is always located closer to the bottom 18 side than the liquid level of the working liquid that increases or decreases in the reservoir chamber 12, and is always immersed in the working liquid in the reservoir chamber 12. The flow path area of the gap between the protruding portion 91 and the cylinder 11 in the reservoir chamber 12 is set to be equal to or larger than the flow path area of the passage 42 of the base member 20.

In the cylinder device 10, when the piston rod 31 of the cylinder device 10 moves to the extension side and the piston 25 moves to the first chamber 28 side, the pressure in the first chamber 28 becomes higher than the pressure in the second chamber 29 by a predetermined value or more. The disc valve 62 provided in the piston 25 opens the passage 65 formed in the piston 25, and the working liquid in the first chamber 28 is passed through the passage 65 and the gap between the disc valve 62 and the piston 25 to the second chamber. 29. At that time, the disc valve 62 controls the flow of the working liquid to generate a damping force.

At this time, the volume in the cylinder 11 is increased by the amount by which the piston rod 31 protrudes from the cylinder 11. The disc valve 46 is separated from the base member 20, opens the passage 43, and supplies the second chamber 29 with the projecting amount of the working liquid from the reservoir chamber 12. At this time, the disk valve 46 opens without substantially becoming a resistance to the flow of the working liquid, and smoothly supplies the working liquid from the reservoir chamber 12 to the second chamber 29. As described above, the working liquid is delivered from the reservoir chamber 12 to the second chamber 29, whereby the liquid level of the reservoir chamber 12 is lowered.

Further, when the piston rod 31 moves to the contraction side and the piston 25 moves to the second chamber 29 side and the pressure in the second chamber 29 becomes higher than the pressure in the first chamber 28 by a predetermined value or more, the cylinder device 10 The disc valve 61 provided in the piston 25 opens the passage 64 formed in the piston 25, and the working liquid in the second chamber 29 is passed through the passage 64 and the gap between the disc valve 61 and the piston 25. Shed. At that time, the disc valve 61 generates a damping force by controlling the flow of the working liquid.

At this time, the volume in the cylinder 11 is reduced by the amount by which the piston rod 31 has entered the cylinder 11. The disc valve 45 is separated from the base member 20, opens the passage 42, and discharges the inflow amount of working liquid from the second chamber 29 to the reservoir chamber 12. Also at that time, the disc valve 45 controls the flow of the working liquid to generate a damping force. As described above, the working liquid is discharged from the second chamber 29 to the reservoir chamber 12, whereby the liquid level of the reservoir chamber 12 rises.

Patent Document 1 described above discloses a hydraulic shock absorber in which a cylindrical elastic body made of rubber or plastic is tightly fitted to at least an outer portion of a cylinder that is in sliding contact with a piston. This cylindrical elastic body absorbs vibration and attenuates sound. In addition, this elastic body prevents the oil jetted into the reservoir during the contraction stroke from reaching the oil surface, disturbing the oil surface, and entraining air. That is, if air is involved in oil, cavitation occurs and the characteristics deteriorate. This elastic body prevents such deterioration of characteristics. Further, Patent Document 2 described above discloses a hydraulic shock absorber in which a heat transfer member fitted between a cylinder and an outer cylinder is provided in a reservoir to improve heat dissipation. In this hydraulic shock absorber, a part of the outer cylinder protrudes inward to form a convex portion, and the heat transfer member is positioned by contacting the convex portion.

If the structure is such that another member is provided between the cylinder and the outer cylinder as in the hydraulic shock absorber disclosed in Patent Documents 1 and 2, the number of parts and the cost will increase. Further, if the structure is such that another member is provided between the cylinder and the outer cylinder, there is a possibility that this part moves and generates abnormal noise.
Further, if the structure is such that another member is provided between the cylinder and the outer cylinder, there is a high possibility that a part of the other member is mixed into the oil liquid and causes contamination. Further, if the structure is such that another member is fitted to the cylinder, the cylinder may be deformed, which may affect the slidability of the piston with respect to the cylinder.

In contrast, in the first embodiment, the outer cylinder 13 is provided with a projecting portion 91 that is formed by plastic deformation and projects in an annular shape toward the cylinder 11. For this reason, the number of parts can be reduced and an increase in cost can be suppressed. Further, since the projecting portion 91 is integrally formed with the outer cylinder 13, it does not move to generate abnormal noise. Further, since the projecting portion 91 is formed integrally with the outer cylinder 13, the occurrence of contamination can be suppressed. Further, since the projecting portion 91 forms a gap with the cylinder 11, the cylinder 11 is not deformed and the sliding performance of the piston with respect to the cylinder is not affected.

The projecting portion 91 narrows the flow path area of the reservoir chamber 12. For this reason, when the working liquid is discharged from the second chamber 29 to the reservoir chamber 12 through the passage 42 by opening the disk valve 45 in the contraction stroke, the jet flow of the working liquid is rectified and the working liquid remains in a turbulent state. Reaching the liquid level in the reservoir chamber 12 can be suppressed. Therefore, it is possible to suppress the working gas from being mixed into the working liquid in the reservoir chamber 12 and becoming foamed. Therefore, it can suppress that the working liquid in a bubbling state is sucked into the second chamber 29 side in the extension stroke. It is possible to suppress the performance degradation of the cylinder device 10 such as disturbance of the damping force waveform caused by the working liquid in the bubbling state being sucked into the second chamber 29 side. Further, since the jet flow of the working liquid can be rectified to prevent the working liquid from reaching the liquid level in the reservoir chamber 12 in a turbulent state, the distance between the liquid level and the base member 20 can be increased. Compared with the case where the jet flow is rectified, the distance between the liquid surface and the base member 20 can be shortened. Therefore, the amount of working liquid can be reduced. Therefore, the weight of the cylinder device 10 can be reduced.

Here, a plurality of projecting portions 91 according to the first embodiment may be provided in the range of the cylindrical portion 17 at intervals in the axial direction. In this way, the rectifying effect of the working liquid in the reservoir chamber 12 by the projecting portion 91 is enhanced, and it is possible to further suppress the working gas from being mixed into the working liquid in the reservoir chamber 12 and becoming foamed.

“Second Embodiment”
Next, the second embodiment will be described mainly based on FIGS. 3 and 4 with a focus on differences from the first embodiment. In addition, about the site | part which is common in 1st Embodiment, it represents with the same name and the same code | symbol.

In the second embodiment, as shown in FIG. 3, a protruding portion 91A that is partially different from the protruding portion 91 of the first embodiment is provided. The projecting portion 91 </ b> A is also provided on the main body member 14 constituting the cylindrical portion 17 of the outer cylinder 13 so as to project annularly from the inner peripheral surface of the main body member 14 toward the cylinder 11. As shown in FIG. 4, the projecting portion 91 </ b> A includes a plurality of projecting configuration portions 111 </ b> A arranged in the circumferential direction, specifically, two locations. The two protruding component parts 111A have the same shape. Therefore, the protruding portion 91A has a pair of protruding configuration portions 111A.

By forming the plurality of projecting component parts 111A, the projecting part 91A has a cut 113A that separates them at a position between the adjacent projecting component parts 111A and the projecting component parts 111A. . The number of cuts 113A is also the same as that of the projecting component 111A, specifically, two places.
The two cuts 113A have the same shape. Therefore, the projecting portion 91A has a pair of cuts 113A. The pair of cuts 113 </ b> A are in the same cylinder as the cylindrical portions 92 and 93 and connect the cylindrical portions 92 and 93 in the axial direction.

As shown in FIG. 3, each protruding component 111A includes a tapered tube portion 101A on the cylindrical portion 92 side, a tapered tube portion 102A on the cylindrical portion 93 side, and a portion between the tapered tube portions 101A and 102A. And a cylindrical portion 103A. Further, the projecting configuration portion 111A has end wall portions 104A shown in FIG. 4 that connect the same sides in the circumferential direction of the tapered split tube portions 101A and 102A and the split cylindrical portion 103A on both sides in the circumferential direction.

The taper tube portion 101 </ b> A shown in FIG. 3 extends from the end portion of the cylindrical portion 92 on the cylindrical portion 93 side. The taper tube portion 101 </ b> A is configured by a part of a conical tube whose diameter decreases as the distance from the cylindrical portion 92 increases. The tapered tube portion 102 </ b> A extends from the end portion of the cylindrical portion 93 on the cylindrical portion 92 side. The tapered tube portion 102 </ b> A is configured by a part of a conical tube whose diameter decreases as the distance from the cylindrical portion 93 increases. The minute cylindrical portion 103A connects the edge portions of the tapered minute tube portions 101A and 102A on the adjacent side. The minute cylindrical portion 103A is constituted by a part of a cylinder. The end wall portions 104A on both sides shown in FIG. 4 have a flat plate shape along the radial direction of the split cylindrical portion 103A.
The protruding component 111A is provided with a recess 115A that is recessed in an annular shape from the outer peripheral surface of the main body member 14 toward the cylinder 11 by the tapered split tube portions 101A and 102A, the split cylindrical portion 103A, and the end wall portions 104A on both sides. Yes.

The inner diameter of the cylindrical portion 103A, which is the minimum diameter portion of the protruding portion 91A, is larger than the outer diameter of the cylinder 11. Between the projecting portion 91A and the cylinder 11 arranged coaxially, a gap is formed which is narrow at the position of the projecting configuration portion 111A and wide at the position of the cut 113A in the radial direction.

The projecting portion 91A is also formed by a plurality of projecting configuration portions 111A constituting the projecting portion 91A by pressing a cylindrical material from the radially outer side toward the radially inner side and plastically deforming it radially inward. Has been. At that time, for example, a pair of punches having a semicircular convex part having the same shape as the concave part 115A is prepared, and a material is pressed so as to be sandwiched between the punches, thereby forming a pair of protrusions including the concave part 115A. A component 111A is formed.

As shown in FIG. 3, the entire protruding portion 91 </ b> A is disposed on the opposite side of the base member 20 from the bottom 18 in the axial direction of the outer cylinder 13. The entire projecting portion 91 </ b> A is always located closer to the bottom 18 than the liquid level of the working liquid that increases or decreases in the reservoir chamber 12, and is immersed in the working liquid in the reservoir chamber 12. The flow passage area of the gap between the protruding portion 91 </ b> A and the cylinder 11 in the reservoir chamber 12 is set to be equal to or larger than the flow passage area of the passage 42 of the base member 20.

In the second embodiment described above, the protruding portion 91A has a plurality of cuts 113A in the circumferential direction as shown in FIG. For this reason, the plurality of projecting constituent portions 111A constituting the projecting portion 91A are independent of each other. As a result, the respective recesses 115A are independent of each other. Therefore, the plurality of projecting constituent portions 111A including the concave portion 115A can be formed by punches that move in the radial direction of the outer cylinder 13. For this reason, a processing man-hour can be reduced and a manufacturing cost can be reduced.

Here, a plurality of protruding portions 91A according to the second embodiment may be provided at intervals in the axial direction to enhance the rectifying effect of the working liquid.

“Third Embodiment”
Next, the third embodiment will be described mainly based on FIGS. 5 to 7 with a focus on differences from the second embodiment. In addition, about the site | part which is common in 2nd Embodiment, it represents with the same name and the same code | symbol.

In the third embodiment, as shown in FIGS. 5 and 6, a plurality of projecting portions 91 </ b> B that are partially different from the projecting portions 91 </ b> A of the second embodiment have different positions in the axial direction of the outer cylinder 13. There are three rows, specifically three rows. A cylindrical portion 121B is formed between the protruding portion 91B and the protruding portion 91B adjacent to each other in the axial direction of the outer cylinder 13. The cylindrical portion 121B is formed by a number smaller than the number of rows of the protruding portions 91B, specifically, two places. The cylindrical portion 121B is in the same cylinder as the cylindrical portions 92 and 93.

The protruding portions 91 </ b> B in each row are also provided on the main body member 14 constituting the cylindrical portion 17 of the outer cylinder 13 so as to protrude in an annular shape from the inner peripheral surface of the main body member 14 toward the cylinder 11. As shown in FIG. 7, each row of protruding portions 91 </ b> B includes a plurality of, specifically, eight protruding configuration portions 111 </ b> B arranged in the circumferential direction. The plurality of projecting components 111B have the same shape.

By forming the plurality of projecting configuration portions 111B, the projecting portions 91B are adjacent to each other at positions between the projecting configuration portions 111B and 111B that are adjacent to each other in the circumferential direction of the cylinder 11. It has the cut 113B which divides the installation component 111B and the protruding component 111B. The number of cuts 113B is also the same as the number of projecting components 111B. The plurality of cuts 113B have the same shape. The cut 113 </ b> B is in the same cylinder as the cylindrical portions 92 and 93.

As shown in FIG. 5, the projecting component 111B includes a tapered tube portion 101B on the cylindrical portion 92 side, a tapered tube portion 102B on the cylindrical portion 93 side, and a divided cylinder portion between the tapered tube portions 101B and 102B. 103B. Further, the projecting component 111B has a pair of end wall portions 104B shown in FIG. 7 that connect the same side in the circumferential direction of the tapered cylindrical portions 101B and 102B and the cylindrical portion 103B on both sides in the circumferential direction.

The tapered part 101B extends from the end of the cylindrical portion 92 or the cylindrical portion 121B on the cylindrical portion 93 side. The taper tube portion 101 </ b> B is constituted by a part of a conical tube having a smaller diameter as it approaches the cylindrical portion 93. The tapered tube portion 102B extends from the end portion of the cylindrical portion 93 or the cylindrical portion 121B on the cylindrical portion 92 side. The tapered split tube portion 102 </ b> B is configured by a part of a conical tube having a smaller diameter as it approaches the cylindrical portion 92. The minute cylinder portion 103B is constituted by a part of a cylinder that connects the edge portions of the tapered minute tube portions 101B and 102B that constitute the same concave portion 115B on the side close to each other. The end wall portions 104B on both sides have a flat plate shape along the radial direction of the minute cylindrical portion 103B. Due to the tapered split tube portions 101B and 102B, the split cylindrical portion 103B, and the end wall portions 104B on both sides, the projecting component 111B is provided with a recess 115B that is recessed in an annular shape from the outer peripheral surface of the body member 14 toward the cylinder 11. Yes.

In the protruding portion 91 </ b> B, the distance from the center of the main body member 14 to this central side surface of the split cylindrical portion 103 </ b> B is larger than the outer diameter of the cylinder 11. Between the plurality of rows of projecting portions 91B and the cylinders 11 arranged coaxially with the projecting portions 91B, a gap is formed that is narrow at the position of the projecting configuration portion 111B and widens radially at the position of the cut 113B. Has been.

As shown in FIG. 6, in the three rows of projecting portions 91B, the projecting portions 91B and the projecting portions 91B adjacent to each other in the axial direction of the outer cylinder 13 project the phase of the projecting configuration portion 111B. The portions 111B are arranged so as to be shifted by a half pitch. As a result, the protruding portion 91B and the protruding portion 91B adjacent to each other in the axial direction of the outer cylinder 13 are such that one protruding component 111B and the other cut 113B are aligned with each other in the circumferential direction. 113B and the other protruding component 111B are aligned in the circumferential direction. In other words, the plurality of rows of projecting portions 91B are configured by a plurality of projecting configuration portions 111B arranged in a staggered manner by shifting the positions of the outer cylinder 13 in the axial direction and the circumferential direction.

The three rows of projecting portions 91B are also formed by the plurality of projecting configuration portions 111B constituting the projecting portions 91B by pressing the material from the radially outer side toward the radially inner side and plastically deforming the material radially inward. Has been. At that time, for example, by preparing a punch in which an arc-shaped convex portion having the same shape as the concave portion 115B is formed and pressing the material with this punch to form the concave portion 115B, three rows of protruding portions 91B are formed. Form.

As shown in FIG. 5, the entire three rows of protruding portions 91 </ b> B are disposed on the opposite side of the base member 20 from the bottom 18 in the axial direction of the outer cylinder 13. Further, the entire three rows of protruding portions 91 </ b> B are always positioned closer to the bottom 18 than the liquid level of the working liquid in the reservoir chamber 12, and are immersed in the working liquid in the reservoir chamber 12. The flow path area of the gap between the protruding portion 91 </ b> B of each row and the cylinder 11 in the reservoir chamber 12 is set to be equal to or larger than the flow path area of the passage 42 of the base member 20.

In the third embodiment described above, the protruding portion 91B also has a plurality of cuts 113B in the circumferential direction. For this reason, the plurality of projecting constituent portions 111B constituting the projecting portion 91B are independent from each other. As a result, the concave portions 115B of the plurality of projecting constituent portions 111B are independent of each other. Therefore, the plurality of projecting constituent portions 111B including the concave portions 115B can be formed by punches that move in the radial direction of the outer cylinder 13. For this reason, a processing man-hour can be reduced and a manufacturing cost can be reduced.

Further, since the projecting portions 91B are provided in a plurality of rows in the axial direction, the effect of rectifying the working liquid in the reservoir chamber 12 by the projecting portions 91B is further enhanced, and the working gas is supplied to the working liquid in the reservoir chamber 12. It is possible to further suppress mixing and foaming.

In addition, since the plurality of projecting components 111B are provided with the axial and circumferential positions of the outer cylinder 13 being shifted, the rectifying effect is further enhanced, and the working gas is mixed into the working liquid in the reservoir chamber 12 and bubbles are generated. It can further suppress that it will be in a state.

“Fourth Embodiment”
Next, the fourth embodiment will be described mainly based on FIG. 8 with a focus on differences from the first embodiment. In addition, about the site | part which is common in 1st Embodiment, it represents with the same name and the same code | symbol.

In the fourth embodiment, a protruding portion 91C that is partially different from the protruding portion 91 of the first embodiment is provided. The protruding portion 91 </ b> C of the fourth embodiment also protrudes in an annular shape from the inner peripheral surface of the main body member 14 constituting the cylindrical portion 17 of the outer cylinder 13 toward the cylinder 11. The protruding portion 91 </ b> C is disposed on the same plane that is inclined with respect to a plane orthogonal to the central axis of the outer cylinder 13. The protruding portion 91C includes a protruding portion 101C on the cylindrical portion 92 side, a protruding portion 102C on the cylindrical portion 93 side, and a connecting portion 103C between the protruding portions 101C and 102C. The protruding portion 91C is also formed by pressurizing the material from the radially outer side toward the radially inner side and plastically deforming the material radially inward.

The protruding portion 101C extends from the end portion of the cylindrical portion 92 on the cylindrical portion 93 side. The protruding portion 101 </ b> C is inclined so as to approach the central axis of the outer cylinder 13 as it approaches the cylindrical portion 93. The protruding portion 102 </ b> C extends from an end edge portion of the cylindrical portion 93 on the cylindrical portion 92 side. The protruding portion 102 </ b> C is inclined so as to approach the central axis of the outer cylinder 13 as it approaches the cylindrical portion 92. 103 C of connection parts have connected the edge part by the side of the cylindrical part 93 of the protrusion part 101C, and the edge part by the side of the cylindrical part 92 of the protrusion part 102C. The protruding portions 101C and 102C and the connecting portion 103C also form a recessed portion 96C that is recessed in an annular shape from the outer peripheral surface of the main body member 14 toward the cylinder 11 in the protruding portion 91C. The flow passage area of the gap between the protruding portion 91 </ b> C and the cylinder 11 in the reservoir chamber 12 is set to be equal to or larger than the flow passage area of the passage 42 of the base member 20.

4th Embodiment described above can suppress the rigidity fall of the outer cylinder 13 because the protrusion part 91C inclines with respect to the direction orthogonal to the center axis line of the outer cylinder 13. As shown in FIG.

Here, a plurality of protruding portions 91C according to the fourth embodiment may be provided at intervals in the axial direction. Moreover, you may form the protrusion part 91C of 4th Embodiment by a some protrusion structure part so that it may have a several cut like 2nd, 3rd embodiment.

“Fifth Embodiment”
Next, the fifth embodiment will be described mainly with reference to FIGS. 9 and 10 focusing on the differences from the first embodiment. In addition, about the site | part which is common in 1st Embodiment, it represents with the same name and the same code | symbol.

In the fifth embodiment, as shown in FIG. 9, a plurality of protruding portions 91 </ b> D that are partially different from the protruding portions 91 of the first embodiment are provided. As shown in FIG. 10, the plurality of projecting portions 91 </ b> D are arranged on the same spiral that turns on the cylindrical portion 17 of the outer cylinder 13 while shifting the axial position around the central axis at a constant rate.

The protruding portion 91D includes a protruding portion 101D on the cylindrical portion 92 side in the axial direction of the outer cylinder 13, a protruding portion 102D on the cylindrical portion 93 side, a connecting portion 103D that connects the protruding portions 101D and 102D, and both sides in the spiral direction. It is comprised from the end wall part 104D of the both sides which connects protrusion part 101D and protrusion part 102D. By the protruding portions 101D and 102D, the connecting portion 103D, and the end wall portions 104D on both sides, the protruding portion 91D is formed with a concave portion 96D that is annularly recessed from the outer peripheral surface of the main body member 14 toward the cylinder 11.

The projecting portion 91D is also formed by using a punch having a convex portion having the same shape as the concave portion 96D to press the material from the radially outer side toward the radially inner side and plastically deform the radially inner side. As a result, the outer cylinder 13 is provided with a plurality of projecting portions 91D that plastically deform the outer cylinder 13 and project toward the cylinder 11 while shifting the positions in the axial direction and the circumferential direction.

According to the fifth embodiment, the working gas is mixed into the working liquid in the reservoir chamber 12 due to the rectifying effect by the plurality of projecting portions 91D provided on the outer cylinder 13, and the foamed state is caused. Can be suppressed. Moreover, the rigidity reduction of the outer cylinder 13 can be suppressed by arrange | positioning several protrusion part 91D on the same spiral.

“Sixth Embodiment”
Next, the sixth embodiment will be described mainly based on FIGS. 11 and 12 with a focus on differences from the first embodiment. In addition, about the site | part which is common in 1st Embodiment, it represents with the same name and the same code | symbol.

In the sixth embodiment, as shown in FIG. 11, the mounting eye 19 of the first embodiment is not provided, and a metal mounting bracket for mounting the cylinder device 10 to the vehicle on the outer peripheral surface of the outer cylinder 13 is provided. 131 is attached. The mounting bracket 131 reinforces the strength reduction of the outer cylinder 13 due to the protruding portion 91. As shown in FIG. 12, the mounting bracket 131 is composed of two parts, a structural body 132 and a structural body 133.

The structural body 132 has a split tube portion 135 and a pair of extending plate portions 136. The split tube portion 135 is constituted by a part of a cylinder attached so as to cover the cylindrical portions 92 and 93 of the main body member 14 of the outer tube 13 and half or more of the protruding portion 91. The pair of extending plate portions 136 extend in parallel from both ends of the split tube portion 135. The structure 133 has a split tube portion 138 and a pair of extending plate portions 139. The split tube portion 138 includes a part of a cylinder that is attached so as to cover portions that are not covered by the cylindrical portions 92 and 93 of the main body member 14 of the outer tube 13 and the split tube portion 135 of the protruding portion 91. The pair of extending plate portions 139 extend in parallel from both ends of the split tube portion 138. The split tube portion 135 is joined to both the cylindrical portions 92 and 93. The split tube portion 138 is joined to both the cylindrical portions 92 and 93. The first extension plate portion 136 is joined to the first extension plate portion 139. The second extension plate portion 136 is joined to the second extension plate portion 139.

Thus, by joining the mounting bracket 131 to both the cylindrical portions 92 and 93 across the protruding portion 91 in the axial direction of the outer cylinder 13, the rigidity of the outer cylinder 13 and the fatigue strength are reduced by the protruding portion 91. Can be reinforced. Therefore, deformation can be suppressed even when a lateral force is applied to the outer cylinder 13. Here, also in the second to fifth embodiments, the mounting bracket 131 can be attached so as to join the cylindrical portions 92 and 93 across the projecting portions 91A to 91D in the axial direction.

The embodiment described above includes a cylinder filled with a working liquid, a piston slidably fitted in the cylinder, and defining a first chamber and a second chamber in the cylinder, and the piston A piston rod connected to the cylinder, an outer cylinder provided on the outer peripheral side of the cylinder and forming a reservoir chamber in which a working liquid and a working gas are sealed between the cylinder and a first end of the cylinder. And a base member that defines the second chamber and the reservoir chamber in the cylinder, and a projecting portion that is formed by plastic deformation and projects annularly toward the cylinder on the outer cylinder Is provided. As a result, it is possible to prevent the working gas from being mixed into the working liquid in the reservoir chamber and bubbling due to the rectifying effect by the projecting portion provided on the outer cylinder.
Since the outer cylinder is provided with a protruding portion that is formed by plastic deformation and protrudes in an annular shape toward the cylinder, the number of parts can be reduced and an increase in cost can be suppressed. Further, since the projecting portion is integrally formed with the outer cylinder, it does not move and does not generate abnormal noise, and the occurrence of contamination can be suppressed. Further, the projecting portion does not cause the cylinder to be deformed, and the slidability of the piston with respect to the cylinder is not affected.

Since the projecting portion has a plurality of cuts in the circumferential direction, the number of processing steps can be reduced, and the manufacturing cost can be reduced.

By providing a plurality of the projecting portions in the axial direction, the effect of rectifying the working liquid in the reservoir chamber by the projecting portions is further enhanced, and the working gas is mixed into the working liquid in the reservoir chamber and becomes a bubbled state. It can further be suppressed.

The rigidity of the outer cylinder can be suppressed by tilting the protruding portion.

The embodiment described above includes a cylinder filled with a working liquid, a piston slidably fitted in the cylinder, and defining a first chamber and a second chamber in the cylinder, and the piston A piston rod connected to the cylinder, an outer cylinder provided on the outer peripheral side of the cylinder and forming a reservoir chamber in which a working liquid and a working gas are sealed between the cylinder and a first end of the cylinder. And a base member that defines the second chamber and the reservoir chamber in the cylinder, and the outer cylinder is provided with a projecting portion that plastically deforms the outer cylinder and projects toward the cylinder. Are provided by shifting the positions in the axial direction and the circumferential direction. As a result, it is possible to prevent the working gas from being mixed into the working liquid in the reservoir chamber and bubbling due to the rectifying effect by the projecting portion provided on the outer cylinder. Since the outer cylinder is provided with a protruding portion that is formed by plastic deformation and protrudes in an annular shape toward the cylinder, the number of parts can be reduced and an increase in cost can be suppressed. Further, since the projecting portion is integrally formed with the outer cylinder, it does not move and does not generate abnormal noise, and the occurrence of contamination can be suppressed. Further, the projecting portion does not cause the cylinder to be deformed, and the slidability of the piston with respect to the cylinder is not affected. Further, the effect of rectifying the working liquid in the reservoir chamber by the protruding portion is further enhanced, and it is possible to further suppress the working gas from being mixed into the working liquid in the reservoir chamber and becoming a foamed state.

According to the above cylinder device, the number of parts can be reduced and the cost increase can be suppressed.

DESCRIPTION OF SYMBOLS 10 Cylinder apparatus 11 Cylinder 12 Reservoir chamber 13 Outer cylinder 20 Base member 25 Piston 28 1st chamber 29 2nd chamber 31 Piston rod 91,91A- 91D Protrusion part 113A, 113B A break.

Claims (5)

1. A cylinder filled with working fluid;
   A piston slidably fitted in the cylinder, and defining a first chamber and a second chamber in the cylinder;
   A piston rod coupled to the piston;
   An outer cylinder that is provided on the outer peripheral side of the cylinder and forms a reservoir chamber in which a working liquid and a working gas are enclosed with the cylinder;
   A base member provided at a first end of the cylinder and defining the second chamber and the reservoir chamber in the cylinder;
   Have
   A cylinder device, wherein the outer cylinder is provided with a projecting portion that is formed by plastic deformation and projects annularly toward the cylinder.
2. 2. The cylinder device according to claim 1, wherein the protruding portion has a plurality of cuts in a circumferential direction.
3. 3. The cylinder device according to claim 1, wherein a plurality of the projecting portions are provided in the axial direction.
4. The cylinder device according to any one of claims 1 to 3, wherein the projecting portion is inclined.
5. A cylinder filled with working fluid;
   A piston slidably fitted in the cylinder, and defining a first chamber and a second chamber in the cylinder;
   A piston rod coupled to the piston;
   An outer cylinder that is provided on the outer peripheral side of the cylinder and forms a reservoir chamber in which a working liquid and a working gas are enclosed with the cylinder;
   A base member provided at a first end of the cylinder and defining the second chamber and the reservoir chamber in the cylinder;
   Have
   The cylinder device, wherein the outer cylinder is provided with a plurality of projecting portions that are plastically deformed to project toward the cylinder while shifting the positions in the axial direction and the circumferential direction.

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