WO2021039078A1

WO2021039078A1 - Brake device for track traveling-type machine

Info

Publication number: WO2021039078A1
Application number: PCT/JP2020/024868
Authority: WO
Inventors: 泰造石野
Original assignee: Ｉｈｉ運搬機械株式会社
Priority date: 2019-08-30
Filing date: 2020-06-24
Publication date: 2021-03-04
Also published as: TW202110683A; JP2021035880A; JP7258695B2; CN114286795A; KR20220052947A

Abstract

The present invention is provided with a brake mechanism 40 including: a pressing frame 50 which is installed to protrude in the horizontal direction perpendicular to a rail 4 between the rail 4 and a lower-part equalizer beam 9c (lower equalizer beam) in a lowermost-stage equalizer device; a hydraulic cylinder 13 which is interposed between both horizontal end sections, of the pressing frame 50, perpendicular to the rail 4 and both side surfaces of the lower-part equalizer beam 9c (lower equalizer beam) in the lowermost-stage equalizer device, and which raises/lowers the pressing frame 50; and a brake pad 12 attached to a lower surface of the pressing frame, wherein the hydraulic cylinder 13 is fixed by means of an elastic member 60 that absorbs bending force acting on a piston rod 13b of the hydraulic cylinder 13.

Description

Braking device for orbital machinery

The present invention relates to a braking device for a track-traveling machine.

FIG. 1 shows an example of a container crane as a general orbital traveling machine, where 1 is a container crane, 2 is a port where a container crane 1 is deployed, 3 is a quay in a

port

2, and 4 is a quay 3. The rail is laid so as to extend in a direction orthogonal to the paper surface of FIG. 1, and the traveling device 8 has traveling wheels 7 that can roll along the rail 4 on the support legs 6 of the crane body 5 of the container crane 1. Is installed.

If the container crane 1 is blown by a strong wind during cargo handling work, the traveling of the container crane 1 does not stop against the intention of the driver and runs away, which may cause a collision or collapse with an adjacent machine or a nearby structure. ..

Therefore, as a device for preventing the escape of the orbital traveling machine as described above, there is a clamp device conventionally disclosed in, for example, Patent Document 1. The clamp device includes a pinching mechanism in which a pair of contacts having a pinching portion formed at the tip thereof are connected so that a substantially intermediate portion thereof is rotatable about an axis, and a base end of the contact in the pinching mechanism. A spring mechanism provided in the portion and narrowing between the base ends of the contacts so that the sandwich always rotates the contacts in a closing direction that sandwiches the rail, and the base ends of the pair of contacts. It is provided with a rotary cam for driving the cam receiving portion formed in the above in a direction of pushing open from the inside and releasing the pinching of the rail by the sandwiching portion.

However, since the clamp device disclosed in Patent Document 1 employs a method of sandwiching the rail from both sides, jagged teeth may be provided on the contact surface on the clamp device side in order to increase the coefficient of friction with the rail surface. Or, if the contact surface is hardened to make it look like a file, there is a possibility that the side surface of the rail will be scratched. Further, if the accuracy of the side surface of the rail is low and the dimension from the center line to the side surface in the width direction varies from side to side, or if the rail is corroded, it is pinched by the pinching portion. However, there is a possibility that the tightening force is greatly reduced and a sufficient holding force cannot be obtained.

In order to solve such a problem, a braking device equipped with a fluid pressure cylinder such as a hydraulic cylinder capable of pressing and separating the brake pad in a direction orthogonal to the rolling surface of the traveling wheel of the rail has been developed (for example, Patent Document). 2).

Japanese Unexamined Patent Publication No. 6-72690 JP-A-2015-58805

By the way, in recent years, in an orbital traveling machine such as the container crane 1, there is an increasing demand for a braking device to be provided below the traveling device 8. This is because, in particular, when modifying an existing track-traveling machine, a braking device cannot be provided under a lower frame extending along a rail 4 so as to connect the support legs 6 between the support legs 6 of the crane body 5. This is to deal with such cases.

However, in the conventional braking device as described in Patent Document 2, the length of the fluid pressure cylinder cannot be shortened, so that it is difficult to provide the braking device in the lower part of the traveling device 8.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a braking device for a track-traveling machine that can increase the degree of freedom of installation by eliminating restrictions on the installation location at the time of remodeling.

The present invention comprises an upper equalizer beam and an upper equalizer beam which are oscillatingly arranged at a lower portion of a support leg traveling on a rail in which an intermediate portion is supported by a rocker pin extending in a horizontal direction perpendicular to the traveling direction. It has at least one stage of an equalizer device consisting of a pair of lower equalizer beams in which the intermediate portion is supported by rocker pins extending in the horizontal direction perpendicular to the traveling direction and is oscillatingly arranged at both ends of the traveling direction. In the braking device of a track traveling machine equipped with a traveling device in which traveling wheels that can roll along a rail are arranged at both ends of the traveling direction of the lower equalizer beam in the lower equalizer device.
A pressing frame disposed between the lower equalizer beam and the rail in the lowermost equalizer device so as to project in the horizontal direction orthogonal to the rail, both ends in the horizontal direction orthogonal to the rail of the pressing frame, and the above. A braking mechanism having a fluid pressure cylinder interposed between both side surfaces of the lower equalizer beam in the lowermost equalizer device and raising and lowering the pressing frame, and a brake pad attached to the lower surface of the pressing frame is provided.
The fluid pressure cylinder relates to a braking device of a track-traveling machine fixed via an elastic member that absorbs a bending force acting on a piston rod of the fluid pressure cylinder.

In the braking device of the track traveling machine, the elastic member is a cylinder body of the fluid pressure cylinder fixed to the lower surface of the support bracket protruding from the lower equalizer beam and the lower surface of the support bracket by a fastening member. Intervened between the back and
The tip of the piston rod of the fluid pressure cylinder is preferably screwed into the pressing frame.

Further, in the braking device of the track traveling type machine, a metal plate interposed between the elastic member and the back surface of the cylinder body of the fluid pressure cylinder can be provided.

According to the braking device of the track-traveling machine of the present invention, it is possible to achieve an excellent effect that the degree of freedom of installation can be increased by eliminating the restriction of the installation location at the time of remodeling.

It is an overall side view which shows an example of the container crane as a track traveling machine. It is a front view which shows the Example of the braking device of the track traveling type machine of this invention. It is a schematic block diagram which shows the Example of the braking device of the track traveling type machine of this invention, and is the figure which shows the state which the braking is released. It is an IV-IV arrow view of FIG. It is a schematic block diagram which shows the Example of the braking device of the track traveling type machine of this invention, and is the figure which shows the state which brake is performed. It is a schematic block diagram which shows the reference example of the braking device of the track traveling type machine of this invention, and is the figure which shows the state which the braking is released.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

2 to 5 are examples of the braking device of the track-traveling machine of the present invention, and in the drawings, the parts with the same reference numerals as those in FIG. 1 represent the same objects.

In the container crane 1 as a track traveling machine shown in FIG. 2, a lower frame 6a extending along a rail 4 is provided between the support legs 6 of the crane main body 5 so as to connect the support legs 6, and the lower frame 6a A plurality of traveling devices 8 (two in the example of FIG. 2) are provided on the bottom surface side.

The traveling device 8 includes an upper equalizer beam 9a, an intermediate equalizer beam 9b, a lower equalizer beam 9c, and traveling wheels 7.

The upper equalizer beam 9a is swingably arranged on the bottom surface side of the lower frame 6a with an intermediate portion supported by a rocker pin 10a extending in a horizontal direction perpendicular to the traveling direction. The intermediate portion equalizer beam 9b is swingably arranged at both ends of the upper equalizer beam 9a in the traveling direction, with the intermediate portion supported by rocker pins 10b extending in the horizontal direction perpendicular to the traveling direction. The lower equalizer beam 9c is swingably arranged at both ends of the intermediate portion equalizer beam 9b in the traveling direction, with the intermediate portion supported by rocker pins 10c extending in the horizontal direction perpendicular to the traveling direction.

The traveling wheels 7 are arranged at both ends of the lower equalizer beam 9c in the traveling direction so as to be freely rollable along the rail 4.

In the example shown in FIG. 2, an equalizer device 9A composed of an upper equalizer beam 9a and an intermediate equalizer beam 9b and an equalizer device 9B composed of an intermediate equalizer beam 9b and a lower equalizer beam 9c are formed in two upper and lower stages. Has been done. Incidentally, the upper equalizer beam 9a in the upper equalizer device 9A becomes the upper equalizer beam, and the intermediate equalizer beam 9b becomes the lower equalizer beam. Further, the intermediate portion equalizer beam 9b in the lower equalizer device 9B is a relatively upper equalizer beam, and the lower equalizer beam 9c is a lower equalizer beam. However, depending on the scale of the container crane 1 as the orbital traveling machine, the equalizer device 9A is formed in only one stage, and the traveling wheels 7 are arranged on the lower equalizer beam (in this case, the intermediate equalizer beam 9b). You may. Further, the equalizer device may be formed in three or more upper and lower stages, and traveling wheels 7 that can roll along the rail 4 may be arranged at both ends of the lower equalizer beam in the traveling direction of the lowermost equalizer device.

In the lower equalizer beam 9c (lower equalizer beam), a plurality of plates (two in the examples of FIGS. 3 and 4) are arranged at intervals in the width direction of the rail 4, and the plate members 9 cp are spaced apart from each other. It is configured by arranging the connecting plate material 9cq.

A braking mechanism 40 is arranged in each of the traveling devices 8. However, it is not always necessary to arrange the braking mechanism 40 in each of the traveling devices 8, and the braking mechanism 40 may be one as long as a sufficient braking force can be obtained.

The braking mechanism 40 is attached to a lower equalizer beam 9c (lower equalizer beam) on which the traveling wheel 7 is arranged, and as shown in FIG. 3, a pressing frame 50, a fluid pressure cylinder 13, and a brake pad 12 have.

The pressing frame 50 of the braking mechanism 40 is arranged between the lower equalizer beam 9c (lower equalizer beam) and the rail 4 so as to project in the horizontal direction orthogonal to the rail 4.

The fluid pressure cylinder 13 of the braking mechanism 40 holds the pressing frame 50 between both ends in the horizontal direction orthogonal to the rail 4 of the pressing frame 50 and both side surfaces of the lower equalizer beam 9c (lower equalizer beam). It is equipped to move up and down.

A fixed frame 51 is attached to the lower equalizer beam 9c (lower equalizer beam), and an elastic member 60 (for example, urethane rubber or the like) and a metal plate 70 (for example, urethane rubber or the like) and a metal plate 70 (for example, urethane rubber or the like) are attached to the lower surface of the support bracket 52 projecting from the fixed frame 51. For example, the cylinder body 13a of the fluid pressure cylinder 13 is fixed by a fastening member 80 such as a bolt via a steel plate or the like.

The tip of the piston rod 13b hanging from the cylinder body 13a is screwed into the pressing frame 50 and fixed by a nut 90.

The fixed frame 51 includes stopper portions 51a facing both end surfaces of the pressing frame 50 in the longitudinal direction of the rail 4, and the stopper portions 51a restrain the movement of the pressing frame 50 in the longitudinal direction of the rail 4. (See FIGS. 3 and 4).

As shown in FIG. 4, two fluid pressure cylinders 13 are arranged on one side, but the number of the fluid pressure cylinders 13 can be set to one or three or more as needed.

The brake pad 12 of the braking mechanism 40 is attached to the lower surface of the pressing frame 50.

A fluid pressure unit 14 is connected to the fluid pressure cylinder 13.

The fluid pressure unit 14 is adapted to supply and discharge a working fluid such as oil to the cap side chamber 13c and the rod side chamber 13d of the fluid pressure cylinder 13 and expand and contract the fluid pressure cylinder 13, and the configuration thereof is as follows. Will be described in detail.

The fluid pressure unit 14 is connected to a pumping line 16 extending from a tank 15 in which a working fluid is stored and a cap side chamber 13c (a chamber on the side where the piston rod 13b does not protrude) of the fluid pressure cylinder 13. The rod side line 18 connected to the rod side chamber 13d of the fluid pressure cylinder 13 (the chamber on the side where the piston rod 13b protrudes) and the return line 19 leading to the tank 15 are provided. A pump 21 driven by the motor 20 and a check valve 22 for blocking the backflow of the working fluid pumped by the pump 21 are provided in the middle of the pressure feeding line 16. The pumping line 16 and the return line 19 and the cap side line 17 and the rod side line 18 are connected via a solenoid valve 23, and from the middle of the pumping line 16 between the check valve 22 and the solenoid valve 23. An accumulator 25 is connected to the branched accumulator line 24.

The solenoid valve 23 has a brake operating position 23A and a brake releasing position 23B. The brake operating position 23A communicates the pumping line 16 with the cap side line 17 to introduce the working fluid pumped by the pump 21 into the cap side chamber 13c of the fluid pressure cylinder 13 while introducing the rod side line. By communicating the 18 and the return line 19, the working fluid in the rod side chamber 13d of the fluid pressure cylinder 13 is discharged to the tank 15. The brake release position 23B communicates the pumping line 16 with the rod side line 18 to introduce the working fluid pumped by the pump 21 into the rod side chamber 13d of the fluid pressure cylinder 13 while introducing the cap side. By communicating the line 17 and the return line 19, the working fluid in the cap side chamber 13c of the fluid pressure cylinder 13 is discharged to the tank 15. The solenoid valve 23 is stopped from being energized to the solenoid at the time of an emergency stop (when the power is intentionally shut off in an emergency) and at the time of a power failure, and mechanically switches to the brake operating position 23A by a spring force. There is.

A relief line 26 leading to the tank 15 is branched and connected in the middle of the pressure feed line 16 between the pump 21 and the check valve 22, and the pressure of the working fluid in the pressure feed line 16 is connected in the middle of the relief line 26. A relief valve 27 that opens to return the working fluid to the tank 15 when the pressure exceeds the set pressure is provided.

In the middle of the accumulator line 24, the high pressure switch 28H that operates when the pressure of the working fluid in the accumulator line 24 reaches the high set pressure and the pressure of the working fluid in the accumulator line 24 reach the low set pressure. A low pressure switch 28L that operates at the time and a shutoff valve 28V that is always open (normally open) and closes when the high pressure switch 28H is operated are provided. As a result, when the pressure of the working fluid in the accumulator line 24 reaches the set pressure of the accumulator 25, the high pressure switch 28H is activated to stop the motor 20 of the pump 21 from a control device (not shown). While the shut-off valve 28V closes when a command is output, when the pressure drops below the set pressure of the accumulator 25, the low pressure switch 28L operates to control the motor 20 of the pump 21. The drive command is output from the engine and the shut-off valve 28V is opened.

A drain line 29 for draining the working fluid of the accumulator 25 to the tank 15 is connected in the middle of the accumulator line 24, and a manual on-off valve opened and closed by an operator is connected to the drain line 29. 30 is provided.

Next, the operation of the above embodiment will be described.

As shown in FIG. 3, when the solenoid valve 23 of the fluid pressure unit 14 is switched to the brake release position 23B, the hydraulic fluid fed by the pump 21 is fluid due to the communication between the pumping line 16 and the rod side line 18. While being introduced into the rod side chamber 13d of the pressure cylinder 13, the cap side line 17 and the return line 19 communicate with each other, so that the working fluid of the cap side chamber 13c of the fluid pressure cylinder 13 is discharged to the tank 15. As a result, the piston rod 13b moves in the direction of contracting inside the fluid pressure cylinder 13, the pressing frame 50 is pulled upward, and the brake pad 12 integrated with the pressing frame 50 is the traveling wheel rolling surface 4a of the rail 4. The braking is released, and the container crane 1 can travel.

On the other hand, when the solenoid valve 23 of the fluid pressure unit 14 is switched to the brake operating position 23A from the state shown in FIG. 3, as shown in FIG. 5, the pumping line 16 and the cap side line 17 communicate with each other. While the working fluid pumped by the pump 21 is introduced into the cap side chamber 13c of the fluid pressure cylinder 13, the rod side line 18 and the return line 19 communicate with each other, so that the working fluid in the rod side chamber 13d of the fluid pressure cylinder 13 is released. It is discharged to the tank 15. As a result, the piston rod 13b of the fluid pressure cylinder 13 moves in the protruding direction, the pressing frame 50 is pushed down, and the brake pad 12 integrated with the pressing frame 50 is pressed against the traveling wheel rolling surface 4a of the rail 4. Braking is performed.

When the pressure of the working fluid in the accumulator line 24 reaches the high set pressure of the accumulator 25, the high pressure switch 28H is activated to operate the motor 20 of the pump 21 from a control device (not shown). A stop command is output and the shutoff valve 28V closes. On the other hand, when the pressure drops below the lower set pressure of the accumulator 25, the lower pressure switch 28L operates, a drive command is output from the control device to the motor 20 of the pump 21, and the shutoff is performed. The valve 28V opens. As a result, the accumulator 25 is constantly stored in a pressure between the high set pressure and the low set pressure. Moreover, the solenoid valve 23 is adapted to mechanically switch to the brake operating position 23A by a spring force by stopping the energization of the solenoid during an emergency stop or a power failure. Further, the shut-off valve 28V is always open (normally open) and is open at the time of emergency stop and power failure. Therefore, in the event of an emergency stop or a power failure, the working fluid accumulated in the accumulator 25 is guided from the accumulator line 24 to the cap side chamber 13c of the fluid pressure cylinder 13 via the cap side line 17, and the piston rod 13b protrudes. The brake pad 12 is pressed against the traveling wheel rolling surface 4a of the rail 4. As a result, even if the pump 21 stops during an emergency stop or a power failure, the brake can be operated.

Here, in general, in the fluid pressure cylinder 13, the back surface side of the cylinder body 13a is pin-connected to the base member, and the tip of the piston rod 13b is pin-connected to the member to be driven. .. However, with such a pin connection structure, the total length is inevitably increased by that amount, and it is inevitable that restrictions on the installation location will increase.

On the other hand, in the case of this embodiment, the back surface side of the cylinder body 13a of the fluid pressure cylinder 13 is fixed to the lower surface of the support bracket 52 by the fastening member 80 although the elastic member 60 and the metal plate 70 are interposed therein. The tip of the piston rod 13b hanging from the cylinder body 13a is screwed into the pressing frame 50 and fixed by a nut 90, and a pin connection structure is not adopted. Therefore, the structure is very advantageous in shortening the total length.

As a result, as described in Patent Document 2 under the lower frame 6a (see FIG. 2) connecting the support legs 6 of the crane main body 5 when remodeling an orbital traveling machine such as the existing container crane 1. Even when the conventional braking device cannot be provided, the braking mechanism 40 can be provided in the lower part of the traveling device 8.

On the other hand, when the pin connection structure is not adopted, a bending force acts on the piston rod 13b of the fluid pressure cylinder 13 when the braking mechanism 40 is operated. However, since the bending force acting on the piston rod 13b of the fluid pressure cylinder 13 is absorbed by the elastic member 60, there is no concern that the fluid pressure cylinder 13 will malfunction, and the life of the fluid pressure cylinder 13 will not be shortened. Be done. Further, by providing the metal plate 70 between the elastic member 60 and the fluid pressure cylinder 13, the load acting on the fluid pressure cylinder 13 can be uniformly dispersed and transmitted to the elastic member 60. Furthermore, since the bending force is absorbed by the elastic member 60 and the mounting accuracy of the fluid pressure cylinder 13 with respect to the support bracket 52 is not strictly required, machining of the surface of the support bracket 52 becomes unnecessary, leading to cost reduction. It will be.

In this way, it is possible to eliminate restrictions on the installation location at the time of remodeling and increase the degree of freedom of installation.

FIG. 6 is a reference example of the braking device of the orbital traveling machine of the present invention, and in the drawings, the parts having the same reference numerals as those in FIGS. 2 to 5 represent the same objects, and the basic configuration is shown in FIG. It is the same as the Example shown in 2 to 5.

In the case of this reference example, the fluid pressure cylinder 13 is provided by disposing a pedestal 65 made of an elastic member such as chloroprene rubber on the upper surface side of the support bracket 52 and tightening the fastening member 80 through the pedestal 65. It is fixed to the lower surface of the support bracket 52.

Next, the operation of the above reference example will be described.

In this reference example, although the total length is increased by the amount that the pedestal 65 is arranged, the bending force acting on the piston rod 13b of the fluid pressure cylinder 13 when the braking mechanism 40 is operated is absorbed by the elastic member 60. At the same time, it is also absorbed by the pedestal 65, and the movable range of the fluid pressure cylinder 13 is widened, so that the effect of making the trouble less likely to occur is further enhanced, which is more advantageous in avoiding a decrease in the life of the fluid pressure cylinder 13.

Since other actions are the same as those of the examples shown in FIGS. 2 to 5, the description thereof will be omitted.

Then, in the case of the embodiment shown in FIGS. 2 to 5, the elastic member 60 is a fastening member on the lower surface of the support bracket 52 protruding from the lower equalizer beam 9c as the lower equalizer beam and on the lower surface of the support bracket 52. The tip of the piston rod 13b of the fluid pressure cylinder 13 is screwed into the pressing frame 50 so as to be interposed between the back surface of the cylinder body 13a of the fluid pressure cylinder 13 fixed at 80. With this configuration, it is not necessary to adopt a pin connection structure for the installation of the fluid pressure cylinder 13, the total length can be shortened, and the braking mechanism 40 can be provided in the lower part of the traveling device 8.

Further, in the case of the embodiment shown in FIGS. 2 to 5, a metal plate 70 interposed between the elastic member 60 and the back surface of the cylinder body 13a of the fluid pressure cylinder 13 is provided. With this configuration, the load acting on the fluid pressure cylinder 13 can be uniformly dispersed and transmitted to the elastic member 60.

The braking device for the track-traveling machine of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

1 Container crane (orbital traveling machine)
2 Port 3 Quay 4 Rail 4a Traveling wheel rolling surface 5 Crane body 6 Support leg 6a Lower frame 7 Traveling wheel 8 Traveling device

9A Equalizer device

9B Equalizer device 9a Upper equalizer beam (upper equalizer beam)
9b Middle equalizer beam (lower equalizer beam (upper equalizer beam))
9c Lower equalizer beam (lower equalizer beam)
9cp Plate material 9cq Plate material

10a Rocker pin

10b Rocker pin

10c Rocker pin 12 Brake pad 13 Fluid pressure cylinder

13a Cylinder body

13b Piston rod 13c Cap side chamber 13d Rod side chamber 14 Fluid pressure unit 15 Tank 16 Pumping line 17 Cap side line 18 Return line 20 Motor 21 Pump 22 Check valve 23 Solenoid valve 23A Brake operation position 23B Brake release position 24 Accumulation line 25 Accumulator 26 Relief line 27 Relief valve 28H High pressure switch 28L Low pressure switch 28V Shutoff valve 29 Drain line 30 Manual opening and closing Valve 40 Braking mechanism 50 Pressing frame 51 Fixed frame 51a Stopper 52 Support bracket 60 Elastic member 65 Pedestal 70 Metal plate 80 Fastening member 90 Nut

Claims

An upper equalizer beam and both ends of the upper equalizer beam in the traveling direction are arranged so as to be swingably arranged at the lower part of a support leg traveling on a rail by supporting an intermediate portion by a rocker pin extending in a horizontal direction perpendicular to the traveling direction. The lowermost equalizer device has at least one stage of an equalizer device consisting of a pair of lower equalizer beams in which the intermediate part is supported by a rocker pin extending in the horizontal direction perpendicular to the traveling direction and is arranged swingably. In the braking device of a track-traveling machine equipped with a traveling device in which traveling wheels that can roll along a rail are arranged at both ends of the lower equalizer beam in the traveling direction.
A pressing frame disposed between the lower equalizer beam and the rail in the lowermost equalizer device so as to project in the horizontal direction orthogonal to the rail, both ends in the horizontal direction orthogonal to the rail of the pressing frame, and the above. A braking mechanism having a fluid pressure cylinder interposed between both side surfaces of the lower equalizer beam in the lowermost equalizer device and raising and lowering the pressing frame, and a brake pad attached to the lower surface of the pressing frame is provided.
The fluid pressure cylinder is a braking device for a track traveling machine fixed via an elastic member that absorbs a bending force acting on a piston rod of the fluid pressure cylinder.
The elastic member is interposed between the lower surface of the support bracket projecting from the lower equalizer beam and the back surface of the cylinder body of the fluid pressure cylinder fixed to the lower surface of the support bracket by a fastening member.
The braking device for an orbital traveling machine according to claim 1, wherein the tip of the piston rod of the fluid pressure cylinder is screwed into the pressing frame.
The braking device for a track-traveling machine according to claim 2, further comprising a metal plate interposed between the elastic member and the back surface of the cylinder body of the fluid pressure cylinder.