JPH07139574A - Cylinder for hydro-pneumatic suspension - Google Patents

Abstract

PURPOSE:To improve durability of a diaphragm and prevent occurrence of gas permeability in a gas chamber by providing the diaphragm composed of laminated resin films of gas impermeability and forming a volumetric fluctuation part whose shape or position is varied. CONSTITUTION:A diaphragm 53 is composed of a resin laminated film having gas-impermeable property, and engaged with a flange of an insertion member 12 arranged in an outer cylinder 1 and an upper end of a plug 25 in an air-tight manner. It is divided into a gas chamber 51 in which external N gas is charged and a liquid chamber 52 which is communicated with an operation chamber 21 through an oil passage 24. A bent portion 54 formed in a form of pleats is extended circumferentially and formed cylindrically. When the pressure in the operation chamber 21 is high, the pressure of oil in the liquid chamber 52 is also high. Thus, the diaphragm 53 is inverted in the outward direction of the diameter, and volume fluctuation in a high pressure chamber 5 is enabled without extending and contracting the diapragm 53 itself. Durability of the diaphragm 53 is thus improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder for a hydropneumatic suspension, and more particularly to a gas impermeable diaphragm for partitioning a high pressure chamber between an outer cylinder and a cylinder inside the outer cylinder into a gas chamber and a liquid chamber. The present invention relates to a cylinder for hydropneumatic suspension using a laminated diaphragm including the resin film.

[0002]

2. Description of the Related Art FIG. 9 shows a conventional self-leveling absorber, which is a type of cylinder for hydropneumatic suspension, and has its upper end locked to a wall forming a low pressure chamber L with an outer cylinder O. At the same time, a gas chamber K and a liquid chamber F are partitioned by an elastic rubber diaphragm D whose lower end is locked to a plug P inserted in the lower portion of the outer cylinder O, and the gas chamber K is accompanied by a change in pressure. The change in volume of the liquid chamber F is realized by expansion and contraction (change in diameter) of the diaphragm D in the circumferential direction.

[0003]

In the conventional self-leveling absorber described above, since the diaphragm D is made of rubber in order to utilize the elasticity, the burst is weak and the durability is not sufficient as a gas separation diaphragm. There is a problem that the gas in the gas chamber K is transmitted.

Further, when a gas-impermeable resin film is used to solve the above gas permeation problem, there is a problem that it is difficult to realize volume change because expansion and contraction are difficult.

Therefore, the present inventors constructed the diaphragm by a laminated diaphragm including a gas-impermeable resin film, and formed a volume changing portion, and changed the shape and position of the gas by inverting / moving or changing the shape of the gas. After reaching the technical idea of the present invention of realizing volume change without expansion and contraction of the impermeable resin film itself, and further research and development, as a result, the durability of the diaphragm is improved and the gas chamber The present invention has reached the purpose of preventing gas permeation and achieving the purpose of realizing volume change without expansion and contraction of the membrane.

[0006]

A cylinder for a hydropneumatic suspension according to the present invention (a first invention according to claim 1) includes an outer cylinder locked to one of a vehicle body and a wheel and an outer cylinder. A cylinder provided, a piston rod that is locked to the other of the vehicle body or the wheel and is inserted in the cylinder, a working chamber formed in the cylinder filled with liquid, and the outer cylinder. In a hydropneumatic suspension cylinder provided with a substantially cylindrical diaphragm that is disposed between the cylinder and divides a gas chamber and a liquid chamber communicating with the working chamber, the diaphragm is a gas. In addition to being a laminated diaphragm containing an impermeable resin film,
A volume changing portion whose shape or position can be changed is formed.

In the cylinder for hydropneumatic suspension of the present invention (the second invention according to claim 2), in the first invention, the shape of the volume changing portion is reversed when the pressure of the liquid in the liquid chamber increases. It is configured by a bent portion.

In the hydropneumatic suspension cylinder according to the present invention (the third invention according to claim 3), in the first invention, the volume changing portion is an absorber of the absorber in response to a change in the pressure of the liquid in the liquid chamber. It is composed of a movable part whose position in the axial direction can be changed.

The hydropneumatic suspension cylinder of the present invention (the fourth invention according to claim 4) is the cylinder for a hydropneumatic suspension according to the first invention, wherein a large number of the bent portions extend in the circumferential direction of the absorber.

In the hydropneumatic suspension cylinder of the present invention (the fifth invention according to claim 5), in the first invention, the movable portion extends in the axial direction of the absorber in a large number to form a tubular shape. The bent portion is configured as described above.

In the hydropneumatic suspension cylinder of the present invention (the sixth invention according to claim 6), in the first invention, the diaphragm is a hollow ring having the bent portion formed in the axial direction of the inner and outer circumferences. It is composed of a tube.

In the hydropneumatic suspension cylinder of the present invention (the seventh invention according to claim 7), in the first invention, at least one end of the diaphragm of the movable portion is locked, and the outer cylinder or the cylinder. The sliding member is configured to slide on the peripheral wall of the cylinder.

[0013]

In the cylinder for hydropneumatic suspension according to the first aspect of the present invention, when the pressure in the working chamber changes due to the piston rod moving up and down in the cylinder, the outer chamber is in communication with the working chamber. Since the pressure of the liquid chamber formed in the cylinder changes, the volume change of the gas chamber and the liquid chamber is realized by changing the shape or position of the volume changing portion formed in the diaphragm. .

In the cylinder for hydropneumatic suspension according to the second aspect of the present invention, the shape of the bent portion forming the volume changing portion is changed by reversing when the pressure of the liquid in the liquid chamber increases, The volume change of the gas chamber and the liquid chamber is realized in the outer cylinder.

In the hydropneumatic suspension cylinder according to the third aspect of the present invention having the above structure, the movable portion changes the axial position of the absorber in accordance with the change in the pressure of the liquid in the liquid chamber, whereby the outer cylinder is formed. The volume change of the gas chamber and the liquid chamber is realized inside.

In the cylinder for hydropneumatic suspension according to the fourth aspect of the present invention, each of the bent portions extending in the circumferential direction of the absorber reverses when the pressure of the liquid in the liquid chamber increases. As a result, the shape is changed, and the volume change of the gas chamber and the liquid chamber is realized in the outer cylinder.

In the cylinder for hydropneumatic suspension according to the fifth aspect of the present invention having the above-mentioned structure, a plurality of the bending parts that extend in the axial direction of the absorber and constitute the movable part configured to have a tubular shape are provided. By changing the axial position of the absorber according to the change of the liquid pressure in the liquid chamber, the volume change of the gas chamber and the liquid chamber in the outer cylinder is realized.

In the hydropneumatic suspension cylinder according to the sixth aspect of the present invention, the bent portion formed in the axial direction on the inner and outer circumferences of the hollow annular tube that constitutes the diaphragm has the pressure of the liquid in the liquid chamber. When is increased, the shape is inverted to change the shape, and the volume change of the gas chamber and the liquid chamber is realized in the outer cylinder.

In the hydropneumatic suspension cylinder according to the seventh aspect of the present invention having the above structure, the position is changed by the sliding member having one end of the diaphragm being slid on the outer wall of the outer cylinder or the cylinder. However, the volume change of the gas chamber and the liquid chamber is realized in the outer cylinder.

[0020]

In the hydropneumatic suspension cylinder according to the first aspect of the present invention, which has the above-described operation, the diaphragm disposed in the outer cylinder is composed of a laminated diaphragm including a gas-impermeable resin film. , The effect of preventing the permeation of gas in the gas chamber, realizing a volume change by changing the shape and position of the volume changing portion without expanding and contracting the diaphragm itself, and improving the durability of the diaphragm. Play.

The hydropneumatic suspension cylinder according to the second aspect of the present invention, which achieves the above-mentioned action, realizes a volume change due to the shape change associated with the reversal of the bent portion without expansion and contraction of the diaphragm itself, so that the durability of the diaphragm is improved. Has the effect of improving.

The hydropneumatic suspension cylinder according to the third aspect of the present invention, which achieves the above-mentioned operation, realizes a smooth volume change by axial movement of the absorber of the movable part without expansion and contraction of the diaphragm itself, and at the same time, the diaphragm. Has the effect of improving the durability of.

In the hydropneumatic suspension cylinder according to the fourth aspect of the present invention, which has the above-described operation, the shape change accompanying the reversal of each bent portion extending in the circumferential direction of the absorber without expansion and contraction of the diaphragm itself. With this, it is possible to realize a large volume change and to improve the durability of the diaphragm.

In the cylinder for hydropneumatic suspension according to the fifth aspect of the present invention, the movement of the bent portion constituting the movable portion extending in the axial direction of the absorber without expansion and contraction of the diaphragm itself is moved. Since the volume change is realized by the change in the position associated with the above, there is an effect that the durability of the diaphragm is improved.

In the cylinder for hydropneumatic suspension of the sixth aspect of the present invention, the bending portion formed in the axial direction of the inner and outer circumferences of the annular tube forming the diaphragm is expanded without expansion and contraction of the diaphragm itself. A large volume change is realized by the shape change due to, and the durability of the diaphragm is improved.

The hydropneumatic suspension cylinder according to the seventh aspect of the present invention, which has the above-described operation, is greatly affected by the change in the position due to the sliding of the sliding member having one end of the diaphragm locked without the expansion or contraction of the diaphragm itself. The volume change is realized, and the durability of the diaphragm is improved.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) The self-leveling absorber of the first embodiment is an embodiment of the above-mentioned first, second and fourth inventions, and is locked to the vehicle body as shown in FIGS. 1 and 2. Outer cylinder 1 and a cylinder 2 arranged in the outer cylinder 1.
And a piston rod 3 having a piston 31 that is locked to a wheel and is inserted in the cylinder 2 and that has an orifice formed therein, and that is provided with an outlet valve 36.
A pump rod 4 having one end locked in the outer cylinder 1 and inserted in the piston rod 3, a working chamber 21 formed in the cylinder 2 and filled with oil, and the inner cylinder 1 Gas chamber 51 of the high-pressure chamber 5 constituting a gas spring arranged in the
And a liquid chamber 52 that communicates with the working chamber 21. The gas-impermeable resin laminated film is formed, and a bent portion 54 extending in the circumferential direction of the absorber that can change its shape is formed to form the gas. The chamber 51 and the liquid chamber 52 are composed of a diaphragm 53 that allows a volume change.

The outer cylinder 1 is composed of a hollow cylindrical body 10 with a bottom, a vehicle body engaging portion 11 is formed at the upper end of the bottom portion, and an insertion member 12 having a U-shaped vertical cross section is inserted at the bottom portion. A low pressure chamber 13 is formed between the inner wall and the insertion member 12, an oil reservoir 14 is formed in the lower portion of the low pressure chamber 13, and a communication pipe 15 is arranged in the oil reservoir 14.

The cylinder 2 is composed of a hollow cylindrical body 20 with a bottom in which a working chamber 21 is formed. The cylinder 2 is inserted into the bottom of the insertion member 12 of the outer cylinder 1 with the bottom facing upward, and the bottom center. Has a hole 22 for inserting the pump rod 4, an opening 23 for connecting the working chamber 21 and the liquid chamber 52 of the high-pressure chamber 5, and an outer peripheral wall and an inner peripheral wall of the interposing member 12. An oil passage 24 communicating with the liquid chamber 52 is formed between the above and the lower end, and an annular plug 25 is provided at the lower end between the lower end and the lower end of the outer cylinder 1.

The piston rod 3 has the plug 25.
Is formed of a small-diameter hollow cylindrical body 30 having a pump chamber 32 formed therein and having a pump chamber 32 formed therein. A locking portion 34 for locking a wheel supporting member is formed at a lower end thereof, and a locking valve 34 serving as a damping valve is formed at an upper end thereof. A piston 31 having an orifice formed therein is fixed, a control sleeve 33 made of a thin, small-diameter hollow cylindrical body is inserted inside, and an outlet valve 36 urged upward in the figure by a spring at the lower end of the control sleeve 33. And an oil passage 35 that connects the pump chamber 31 and the working chamber 21 is formed between the outer peripheral wall of the control sleeve 33 and the inner peripheral wall of the piston rod.

The pump rod 4 is composed of a small-diameter hollow cylindrical body 40, the upper end of which is locked to the bottom of the outer cylinder 1 via a cushion 41, and the inner and outer peripheral walls are connected to substantially the center in the longitudinal direction. A control opening 42 for determining a target vehicle height is formed, and a lower end is provided with an inlet valve 43 which is connected to the pump chamber 32 and is biased by a spring upward in the drawing. It communicates with the oil reservoir 14 via the communication pipe 15.

A pump chamber 32 is formed in the piston rod 3 into which the pump rod 4 is inserted. Inlet valve 43 formed in the pump rod 4
Communicates with the low pressure chamber 13 and the pump chamber 3
I have contacted 2. An outlet valve 36 formed in the piston rod 3 communicates with the pump chamber 32 and the working chamber 21 communicating with the high pressure chamber 5.

Therefore, when the absorber extends, oil is supplied from the pump chamber 32 to the working chamber 21 via the outlet valve 36, and conversely when the absorber contracts, oil is supplied from the oil reservoir 14 via the inlet valve 43. Is configured to be supplied.

The diaphragm 53 is formed of a laminated film of gas impermeable resin, and is airtightly engaged with the flange portion of the insertion member 12 disposed in the outer cylinder 1 and the upper end of the plug 25. It is stopped and partitioned into a gas chamber 51 filled with N ₂ gas on the outside and a liquid chamber 52 communicating with the working chamber 21 via the oil passage 24, and as shown in FIG. The bent portion 54 is formed so as to extend in a pleated shape in the direction, and has a tubular shape.

In the self-leveling absorber of the first embodiment having the above structure, when the pressure in the working chamber 21 is high and the piston 31 is pushed downward in FIG. 1 and the absorber extends, the pump rod 4 is relatively moved. Moves upward, the oil in the oil reservoir 14 enters the pump rod 4 through the communication pipe 15 and the cushion 41, and when the pressure in the pump chamber 32 is low, the oil in the pump chamber 32 passes through the inlet valve 43. Flow into. When the piston 31 is pushed down, the control opening 42 formed at the substantially center of the pump rod 4 is formed in the working chamber 21.
When exposed to the oil, the oil in the working chamber 21 flows into the pump rod 4 through the control opening 42, and the oil reservoir 14 passes through the cushion 41 and the communication pipe 15.
Since it flows in, the pressure in the working chamber 21 drops and the height of the absorber is limited there.

Contrary to the above, when the pressure in the working chamber 21 is low and the absorber contracts, when the oil pressure in the pump chamber 31 rises and exceeds a certain value, the urging force of the spring of the outlet valve 36 is overcome. It flows out of the pump chamber 32 and flows into the working chamber 21 through an oil passage 35 formed between the control sleeve 33 and the piston rod 3 to increase the pressure in the working chamber 21.

When the pressure in the working chamber 21 is high, the pressure of the oil in the liquid chamber 52 constituted by the oil chamber communicating with the working chamber 21 through the opening 23 and the oil passage 24 is also high. Therefore, the diaphragm 53 arranged between the gas chamber 51 and the gas chamber 51 is inverted outward in the radial direction as shown by the broken line in FIG. 2 to change the volume of the high pressure chamber 5 without expanding and contracting the diaphragm 53 itself. It makes it possible.

In the self-leveling absorber of the first embodiment having the above-mentioned operation, since the diaphragm 53 arranged in the outer cylinder 1 is made of a gas impermeable resin film, the gas in the gas chamber 51 is prevented from permeating. 2 to prevent the diaphragm 53 itself from expanding and contracting, and to form a plurality of reversing portions formed in the circumferential direction of the absorber forming the bent portion 54 in the radial direction outward as shown in FIG. With this, a large volume change is realized, and the durability of the diaphragm 53 is improved.

(Second Embodiment) The self-leveling absorber of the second embodiment is an embodiment of the above-mentioned first, third and seventh inventions. As shown in FIG. 3, the lower end of the diaphragm 253 is attached to the cylinder 2. By engaging with the annular member 251 as the sliding member that constitutes the movable portion that slides on the outer peripheral wall,
Diaphragm 253 made of gas impermeable resin laminated film
Are bent and arranged in a J-shape in a vertical section so as to partially overlap with each other, and the annular member 251 slides up and down in accordance with a change in pressure of the liquid chamber 52, so that the overlapping portion of the bent portions overlaps each other. It differs from the first embodiment only in that the length is changed to realize the volume change, and the other configurations are the same, and the description thereof is omitted.

The self-leveling absorber of the second embodiment having the above structure does not expand or contract the diaphragm 253 itself made of a gas impermeable resin film, and is an annular member as a sliding member forming the movable part. Since a smooth volume change is realized by sliding 251 on the outer peripheral wall of the cylinder 2, there is an effect that the durability of the diaphragm is improved.

(Third Embodiment) The self-leveling absorber of the third embodiment is an embodiment of the above-mentioned first, third and fifth inventions, and is arranged in the outer cylinder 1 as shown in FIG. The upper portion of the diaphragm 353 made of a gas-impermeable resin laminated film that is airtightly locked to the flange portion of the insertion member 12 is constituted by a large-diameter bent portion 354, and is inserted at the lower end of the outer cylinder 1. The lower portion of the diaphragm 353, which is airtightly locked to the plug 25, is composed of a small-diameter bent portion 355.
Is different from the first embodiment only in the configuration that can increase the length of the liquid chamber 52 to increase the volume of the liquid chamber 52, and the other configurations are the same, so the description thereof will be omitted.

The self-leveling absorber of the third embodiment having the above structure is made of a gas-impermeable resin film because the large-diameter bent portion 354 becomes longer as the pressure in the working chamber 21 becomes higher. The position of the connection point of the large-diameter bent portion 354 and the small-diameter bent portion 355 forming the movable portion smoothly changes according to the pressure change of the liquid chamber 52 without expansion and contraction of the diaphragm 353 itself. Since the volume change is realized by this, there is an effect that the durability of the diaphragm is improved.

(Fourth Embodiment) The self-leveling absorber of the fourth embodiment is an embodiment of the above-mentioned first, third and seventh inventions, and as shown in FIG. A diaphragm 453 made of an annular gas-impermeable resin laminated film is inserted between the sliding outer ring 451 and the inner ring 452 sliding on the outer peripheral wall of the cylinder 2, and the upper gas chamber 51 and the lower gas chamber 51 are inserted. Liquid chamber 52 in communication with working chamber 21
When the pressure of the working chamber 21 becomes high, the diaphragm 453 moves up and down together with the inner and outer rings 451 and 452 as the sliding members, and the volume of the liquid chamber 52 can be increased. The third embodiment is different from the first embodiment, and the other parts have the same configuration, and thus the description thereof is omitted.

In the self-leveling absorber of the fourth embodiment having the above structure, when the pressure in the working chamber 21 becomes high, the diaphragm 45 together with the inner and outer rings 451 and 452.
Since 3 moves up and down, the positions of the inner and outer rings 451 and 4524 and the diaphragm 453 that form the movable portion change smoothly without the expansion and contraction of the diaphragm 453 itself made of a gas impermeable resin film. Since the volume change is realized, the durability of the diaphragm can be improved, the diaphragm 453 can be made into a free piston, and the inner and outer races 451 and 452 are connected by the diaphragm 453, so that there is a possibility of misalignment. There is no effect.

(Fifth Embodiment) The self-leveling absorber of the fifth embodiment is the embodiment of the above-mentioned first, second, fourth and fifth inventions, and is arranged in the circumferential direction of the diaphragm of the first embodiment. Instead of the extended bent portions, as shown in FIG. 6, a large number of dimples 551 protruding radially inward like a golf ball are provided over the entire surface of a diaphragm 553 made of a gas impermeable resin laminated film. When the pressure is increased, the dimples 551 reversely project outward in the radial direction, thereby making it possible to increase the volume of the liquid chamber 52, which is the difference from the first embodiment.
The other parts have the same configuration, and thus the description thereof will be omitted.

In the self-leveling absorber of the fifth embodiment having the above-mentioned structure, the dimples 551 project outward in the radial direction when the pressure in the working chamber 21 rises, so that the self-leveling absorber is made of a gas impermeable resin film. Since the volume change of the liquid chamber 52 is realized without the expansion and contraction of the diaphragm 453 itself, the durability of the diaphragm is improved, and the large volume change is realized by the deformation of the dimple 551.

(Sixth Embodiment) The self-leveling absorber of the sixth embodiment is the embodiment of the above-mentioned first, second, fifth and sixth inventions, and as shown in FIG. 7, is a gas impermeable resin. A diaphragm made of a laminated film is composed of a hollow annular tube 653 having a bent portion 651 formed in the inner and outer circumferences in an axial direction, and is filled with N ₂ gas to form a gas chamber, and a liquid chamber is formed outside. The second embodiment is different from the first embodiment only in the point that it is configured as described above, and the description is omitted because the other configurations are the same.

In the self-leveling absorber of the sixth embodiment having the above structure, when the pressure in the working chamber 21 increases, the bent portion 6 formed on the inner and outer circumferences of the annular tube 653.
Since 51 is inverted and the height becomes low, the volume change of the liquid chamber 52 is realized without expansion and contraction of the diaphragm 453 itself made of a gas-impermeable resin film, so that the durability of the diaphragm is improved. In addition to the improvement, there is an effect that a large volume change can be realized by the collapse of the annular tube 653.

The above-mentioned embodiments are given as examples for explanation, and the present invention is not limited to them. Those skilled in the art can understand from the claims, the detailed description of the invention and the description of the drawings. Modifications and additions can be made without departing from the technical idea of the present invention that can be recognized.

In each of the above-mentioned embodiments, an example in which a high-pressure chamber composed of a gas chamber and a liquid chamber is provided in the outer cylinder has been described, but the present invention is not limited to this.
Guide the hydraulic pressure of the working chamber to the high pressure chamber outside the outer cylinder by the pipe,
It is also possible to adopt a mode in which the diaphragm having the volume changing portion is arranged in the high pressure chamber.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a transverse cross-sectional view showing a diaphragm of the first embodiment.

FIG. 3 is a vertical sectional view showing a second embodiment.

FIG. 4 is a vertical sectional view showing a third embodiment.

FIG. 5 is a partial vertical sectional view showing a fourth embodiment.

FIG. 6 is a longitudinal sectional view showing a diaphragm of a fifth embodiment.

FIG. 7 is a partial sectional view showing a sixth embodiment.

FIG. 8 is a perspective view showing a diaphragm of a sixth embodiment.

FIG. 9 is a vertical sectional view showing a conventional example.

[Explanation of symbols]

 1 Outer Cylinder 2 Cylinder 3 Piston Rod 4 Pump Rod 5 High Pressure Chamber 10, 20 Bottomed Hollow Cylindrical Body 11 Locking Part 12 Insertion Member 13 Low Pressure Chamber 14 Oil Reservoir 15 Communication Pipe 21 Working Chamber 22 Hole 23 Opening 24, 35 Oil passage 25 Plug 31 Piston 32 Pump chamber 33 Control sleeve 34 Locking part 36 Outlet valve 40 Hollow cylindrical body 41 Cushion 42 Control opening 43 Inlet valve 51 Gas chamber 52 Liquid chamber 53 Diaphragm 54 Bending part

Front Page Continuation (72) Inventor Osamu Yasuike 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Shuichi Takeuma 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Yukihide Kimura 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (7)

[Claims] 1. An outer cylinder locked to one of a vehicle body or a wheel, a cylinder arranged in the outer cylinder, and an outer cylinder locked to the other of the vehicle body or the wheel and inserted in the cylinder. A piston rod, a working chamber formed in the cylinder and filled with liquid, a gas chamber arranged between the outer cylinder and the cylinder, and a liquid chamber communicating with the working chamber. In a cylinder for a hydropneumatic suspension, which includes a substantially cylindrical diaphragm that partitions, the diaphragm is a laminated diaphragm including a gas-impermeable resin film, and a volume change whose shape or position can change. A cylinder for hydro-pneumatic suspension, characterized in that a portion is formed. 2. The cylinder for hydropneumatic suspension according to claim 1, wherein the volume changing portion is composed of a bent portion whose shape is inverted when the pressure of the liquid in the liquid chamber increases. 3. The hydronuclear device according to claim 1, wherein the volume changing portion is configured by a movable portion that can change a position in the axial direction of the absorber according to a change in liquid pressure in the liquid chamber. Cylinder for Matic suspension. 4. The cylinder for hydropneumatic suspension according to claim 1, wherein a large number of the bent portions extend in a circumferential direction of the absorber. 5. The movable part according to claim 1, wherein a large number of the movable parts extend in the axial direction of the absorber,
A cylinder for a hydropneumatic suspension, characterized by being configured by a bent portion configured to have a tubular shape. 6. The diaphragm according to claim 1, wherein:
A cylinder for a hydropneumatic suspension, characterized by being constituted by a hollow annular tube in which the bent portion is formed in the inner and outer circumferences in the axial direction. 7. The movable part according to claim 1, wherein at least one end of the diaphragm is locked, and the movable part is configured by a sliding member that slides on a peripheral wall of the outer cylinder or the cylinder. Cylinder for hydro-pneumatic suspension.