JPH0762481B2 - Fluid cylinder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid cylinder operated by a pressure fluid such as hydraulic pressure or compressed air. More specifically, a plurality of cylinder chambers are formed in one cylinder unit, and one piston is provided in each cylinder chamber. And a plurality of pistons are fixed to one piston rod. This fluid cylinder is used to increase power.

[0002]

2. Description of the Related Art The basic structure of a fluid cylinder which has been often used conventionally will be described with reference to FIG. The cylinder unit 10 has flanges 10A and 10B at both ends thereof, and has an upper cylinder cover 11 and a lower cylinder cover 12
And are fixed by bolts 16. A cylinder chamber 32 is formed inside the cylinder unit 10, and the piston 13 is slidably and liquid-tightly accommodated therein. The piston 13 is fixed by a nut 15 to one end of a piston rod 14 that is slidably and slidably inserted into a hole formed in the lower cylinder cover 12. Upper cylinder cover 1
1 is provided with a first circulation hole 21 for allowing the pressure fluid to act on the pressurizing surface A side of the piston in the cylinder chamber, and the lower cylinder cover 12 applies the pressure fluid to the rear surface B side of the piston in the cylinder chamber. The 2nd circulation hole 22 for making it be provided. Further, in order to prevent fluid leakage, the piston has a piston ring 19, the upper cylinder cover has a seal 17, and the lower cylinder cover has seals 17, 18.
Are provided respectively.

Explaining the operation of the fluid cylinder, the pressure fluid is first supplied to the first circulation hole 21 of the upper cylinder cover 11 from the switching valve of the pressure fluid supply system (not shown), and the second fluid of the lower cylinder cover 12 is supplied. The flow hole 22 communicates with the drain. Then, the piston 13 is pushed by the fluid and pushes out the piston rod 14, and the output stroke (power stroke) is performed. When the piston rod 14 reaches a predetermined position, a limit switch (not shown) operates to operate the switching valve, and the supply of the pressure fluid is stopped.
When the pressurizing work is completed, the switching valve is operated by the control device (not shown). Then, the pressure fluid is supplied to the rear surface side of the piston 13 in the cylinder chamber 32 through the second circulation hole 22, and the fluid on the pressurizing surface side of the piston 13 returns to the drain through the first circulation hole 21. Thus, the piston 13 is pushed in the direction opposite to the output stroke, and the return stroke is performed. In this case, the back surface B of the piston 13
The area on the side is smaller than the area on the pressing surface A side due to the cross-sectional area of the piston rod 14, but the difference is small, so the speed of the output stroke of the piston and the speed of the return stroke are almost the same.

FIG. 7 shows another example of a conventional fluid cylinder. In this example, the flanges 10A and 10B provided on the cylinder of the example of FIG.
Is sandwiched between the upper cylinder cover 11 and the lower cylinder 12 and fixed with long bolts 16A, the operation of which is exactly the same as that of the cylinder shown in FIG.

[0005]

In order to increase the output of the fluid cylinder, there is no other method than increasing the pressure of the fluid supplied to the cylinder chamber or increasing the inner diameter of the cylinder unit. It was However, if the pressure of the fluid is increased, the piping for supplying the fluid must be able to sufficiently withstand high pressure, and the cylinder, cylinder cover, seal, etc. must also be of high-pressure type. Becomes higher. Also,
There was a practical limit to raising the pressure. On the other hand, if the inner diameter of the cylinder is increased, the dimension of the cylinder in the diameter direction increases, and depending on the purpose of use, it may not be possible to sufficiently increase the size due to the limitation of the mounting location.

It is an object of the present invention to provide a fluid cylinder capable of increasing the output without increasing the pressure of the fluid and increasing the inner diameter of the cylinder.

[0007]

According to the present invention, a cylinder unit axially partitioned into a plurality of cylinder chambers by a partition member, a first cylinder cover fixed to one end of the cylinder unit, and the cylinder unit are provided. A second cylinder cover fixed to the other end, a piston rod slidably supported by penetrating the partition member and the second cylinder cover, and a liquid in each cylinder chamber of the plurality of cylinder chambers. A piston which is densely and slidably accommodated, has a pressure surface and a back surface, and causes a pressure fluid to flow in and out of the piston fixed to the piston rod and the pressure surface side of the piston in each of the cylinder chambers. In the first fluid supply path and the first cylinder chamber of the plurality of cylinder chambers ,
There is a first cylinder cover having the first cylinder cover at one end.
A second fluid supply path for letting a pressurized fluid flow in and out of the rear side of the piston in the cylinder chamber, and a vent hole for communicating the rear side of the piston in each cylinder chamber other than the first cylinder chamber with the outside of the cylinder unit. And the piston rod
On the portion of the second cylinder cover protruding from the
Mounted so that it is substantially parallel to the stone rod
Has a dog for actuating the limit switch
And an auxiliary rod for connecting the second cylinder cover to the second cylinder cover.
The auxiliary rod has pores, and the auxiliary rod has the second cylinder cover.
The second cylinder cover is fixed through the vent hole of
It is possible to enter and exit the existing cylinder chamber .

According to an aspect of the present invention, the first fluid supply passage, said provided first cylinder cover, pressing surface of said first pressure fluid supply pipe first cylinder chamber of the piston And a communication hole that is provided in the piston rod and that communicates the pressure surface sides of the pistons of the plurality of cylinder chambers with each other, and the second fluid supply path is It is composed of a second circulation hole that connects the back side of the piston of the first cylinder chamber and the second pressure fluid supply pipe.

Further, according to another embodiment of the present invention ,
The first fluid supply passage, said provided first cylinder cover, the first flow hole for communicating the pressure face side of the first pressure fluid supply pipe first cylinder chamber of the piston, And a pipe that is provided outside the cylinder unit and that connects the pressurizing surface side of the pistons of the cylinder chambers of the plurality of cylinder chambers, and the second fluid supply path is connected to the piston of the first cylinder chamber. It is composed of a second circulation hole that connects the back side and the second pressure fluid supply pipe.

[0010]

The pressure fluid supplied from the pressure fluid supply system passes through the first pressure fluid supply pipe through the switching valve to the first pressure fluid supply pipe.
Is supplied from the fluid supply path to the piston pressure surface side of each cylinder chamber, and an output of a value obtained by multiplying the fluid pressure to the area obtained by adding the areas of the piston pressure surfaces of the plurality of cylinder chambers is applied to the piron rod. Therefore, as compared with the conventional fluid cylinder having the same inner diameter, the output of a plurality of cylinder chambers, that is, a multiple corresponding to the number of pistons can be obtained.

When the pressure fluid is supplied to the rear side of the piston in the first cylinder chamber from the second fluid supply passage through the second pressure fluid supply pipe, the piston rod is pushed back to its original position. The return process is performed. In this case, the pressure fluid is supplied only to the first cylinder chamber, and the discharge amount of the pump of the pressure fluid supply system (fluid supply flow rate) is almost the same as in the pressurization stroke, so the return speed of the piston is A speed higher than a multiple value corresponding to the number of a plurality of cylinder chambers than the piston moving speed in the output stroke, and a quick return effect can be obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a fluid cylinder of the present invention will be described with reference to the drawings. Referring to FIG. 1 showing a first embodiment of a fluid cylinder according to the present invention, a cylinder unit 100
Is formed by fitting the first cylinder body 101 having the first cylinder chamber 131 and the second cylinder body 102 having the second cylinder chamber 132 on both sides of the partition member 103. 2 in the axial direction by 103
It is divided into two cylinder chambers. Cylinder unit 1
00 to one end of the cylinder unit 111, and the other end to the second cylinder cover 112, and the cylinder unit 1 with a bolt 116 penetrating these cylinder covers.
It is fixed so as to sandwich 00.

A seal 117 is provided at the fitting portion between the first cylinder cover 111 and the first cylinder body 101, and a fitting portion between the first cylinder body 101 and the second cylinder body 102 and the partition member 103, respectively. The seal 118 is arranged and in a liquid-tight state. Through holes are provided in the partition member 103 and the second cylinder cover 112, respectively, and the piston rod 200 is slidably supported through these through holes. A seal 120 is arranged in the through hole of the partition member 103 to be in a liquid-tight state.

The first piston 113 is housed in the first cylinder chamber 131, and the second piston 114 is housed in the second cylinder chamber 132, and they are fixed to the piston rod 200, respectively. These pistons are the piston rod 2
00 can slide in the respective cylinder chambers 131 and 132 integrally. Piston 113 and piston ring 1
41, a piston 114 is provided with a piston ring 142, which maintains liquid-tight contact with the inner walls of the cylinder bodies 101 and 102, respectively. The first piston 113 has a pressure surface A1 and a back surface B1, and the second piston 114 has a pressure surface A2 and a back surface B2.

On the first cylinder cover 111, the pressing surface A1 of the first piston 113 in the first cylinder chamber 131 is provided.
The first flow hole 121 for communicating the side with the first pressure fluid supply pipe 502 of the hydraulic device 500 as the pressure fluid supply system is provided, and the partition member 103 is provided with the first circulation hole 121.
B1 of the first piston 113 of the cylinder chamber 131 of
Side and the second pressure fluid supply pipe 50 of the hydraulic device 500.
The 2nd circulation hole 122 which connects 3 and 3 is provided. Further, the piston rod 200 communicates with the pressurizing surface A1 side of the first piston 113 and the hole 212 provided in the upper part of the second piston 114 on the pressurizing surface A2 side.
11 is provided. As a result, the first piston 113 in the first cylinder chamber 131 is pressed against the pressurizing surface A1 side, and
Pressure surface A of the second piston 114 of the cylinder chamber 132 of
The 2 side is always in communication. In this way, the first circulation hole 121 and the communication hole 211 constitute a first fluid supply path for allowing the pressure fluid to flow into and out of the pressurizing surface side of each piston of the first and second cylinder chambers 131 and 132, By the second circulation hole 122, the first cylinder chamber 1
A second fluid supply passage for allowing pressure fluid to flow in and out of the back surface B2 side of the piston 113 of 31 is configured.

The second cylinder cover 112 is provided with a vent hole 133 for communicating the rear surface B2 side of the second piston 114 of the second cylinder chamber 132 and the outside of the cylinder unit 100.

The first piston 113 is fitted so as to engage with a step formed on the upper end of the piston rod 200, and is fixed with a nut 115. Then, the second piston 114 is fitted so as to engage with a step formed at a predetermined distance from the upper end of the piston rod 200,
The upper surface is brought into contact with the clip 143 and locked. This is because in the first piston 113, the fluid pressure acts alternately on the pressurizing surface A1 side and the back surface B1 side, so
While it is necessary to firmly fix the piston 113 of the second piston 114 to the piston rod in both directions of the output stroke and the return stroke, in the second piston 114, the fluid pressure acts on the pressurizing surface A2 in the output stroke. Since the back surface B2 of the second piston 114 can be subjected to fluid pressure by simply performing the operation, the second piston 114 can be firmly fixed to the piston rod 200 in the direction of the output stroke. The B2 side is received by the stepped portion formed in the piston part 200, and the pressing surface A2 side is locked by the locking clip 143.

The second cylinder cover 112 serves as a rotation stopping means for the piston rod 200, if necessary.
A rotation stopping member 232 is provided, and this is used as a piston rod 20.
It can be slidably brought into contact with the flat surface portion 201 formed on the side surface of No. 0. The details are shown in FIG. The rotation stopping member 232 is fixed by a screw 233. Second
Since the fluid pressure does not act on the cylinder cover 112, it is not necessary to provide a seal. In the conventional fluid cylinder, there is a problem that the pressure fluid leaks when the detent is provided on the cylinder cover. Even if the stop is provided, the pressure fluid does not leak.

Further, if necessary, the piston rod 2
Auxiliary rod 231 is attached to the lower end of the second cylinder chamber 132 of the second piston 114 in parallel with the piston rod 200 and through the ventilation hole 133 of the second cylinder cover 112. The auxiliary rod 231 is extended toward the back surface, and the auxiliary rod 231 has limit switches R1 and R2 for the upper limit and the lower limit of the movement distance of the piston rod 200.
A dog D for operating the can be attached.

Next, the operation of the fluid cylinder of the above-mentioned first embodiment will be described. As shown in FIG. 1, the hydraulic device 500
The oil liquid in the oil tank 504 is
The pressure fluid is supplied to the first circulation hole 121 through the first pressure fluid supply pipe 502 via the switching valve 501. The pressure fluid flows into the pressurizing surface A1 side of the first piston 113 of the first cylinder chamber 131, and further, from the inlet 210 of the communication hole 211 of the piston rod 200 to the communication hole 2.
11 through the hole 212 on the pressurizing surface A2 side of the second piston 114 to the second piston 1 of the second cylinder chamber 132.
It flows into the pressing surface A2 side of 14.

First piston 113 and second piston 1
14 is the output of the piston rod 200 multiplied by the pressure of the oil liquid to the area obtained by adding the area of the pressing surface A2 of the second piston 114 to the area of the pressing surface A1 of the first piston 113 when pressed by the hydraulic pressure. And perform the output process. At the same time, the oil liquid on the rear surface B1 side of the first piston 113 in the first cylinder chamber 131 is discharged into the second circulation hole 122 and the second circulation hole 122.
Is returned to the oil tank through the pressure fluid supply pipe 503 and the switching valve 501.

When the output stroke is completed, the pump 505 is stopped by the control device (not shown), and the supply of the pressure fluid is stopped.

Next, when the pump 505 is re-driven by the control device (not shown) and the switching valve 501 is operated as shown in FIG. 2, the pressure fluid is, contrary to the above, the second fluid pressure supply pipe. 503 from the first through the second circulation hole 122
B1 of the first piston 113 of the cylinder chamber 131 of
Supplied to the side, the first piston 113 is pushed in the opposite direction, and the piston rod 200 performs the return stroke. At this time, the second piston 114 in the second cylinder chamber 132
The oil liquid on the pressurizing surface A2 side of the first cylinder chamber 131 is pushed back to the pressurizing surface A1 side of the first piston 113 of the first cylinder chamber 131 through the hole 212 and the communication hole 211, and It merges with the oil liquid on the pressurizing surface A1 side of the piston 113 to form the first circulation hole 121 and the first pressure fluid supply pipe 50.
2 and the switching valve 501, and is returned to the oil tank 504. Then, when the return stroke is completed, the pump 505 is stopped by the control device (not shown), and the supply of the pressure fluid is stopped.

Next, a second embodiment of the present invention will be described with reference to FIG. The cylinder unit 100 includes a first cylinder body 101 having a first cylinder chamber 131 and a second cylinder body 11 having a second cylinder chamber 132.
4 are fitted to both sides of the first partition member 103, and the third cylinder body 104 having the third cylinder chamber 152 is attached to the second cylinder body 102 via the second partition member 105. It is formed by being connected to each other, and is partitioned into three cylinder chambers in the axial direction by two partition members 103 and 105. A first cylinder cover 111 is fixed to one end of the cylinder unit 100, and a second cylinder cover 112 is fixed to the other end of the cylinder unit 100 via bolts 116 so as to sandwich the cylinder unit 100.

A hole is provided in the second partition member 105, and the piston rod 200 is slidably and liquid-tightly passed therethrough. Then, in the third cylinder chamber 152, the third piston 151 having the pressing surface A3 and the back surface B3 is
It is slidably and liquid-tightly accommodated in the inner wall of the third cylinder body 104. Like the second piston 114, the third piston 151 is fixed to a predetermined position of the piston rod 200 and locked by a locking clip 144.

The piston rod 200 has an inlet 21 at the upper end.
From 0, the hole 21 on the pressure surface A2 side of the second piston 114
2 and a hole 213 on the pressurizing surface A3 side of the third piston 151.
And a communication hole 211 communicating with
The pressurizing surface A1 side of the first piston 113 of the first cylinder chamber 131, the pressurizing surface A1 side of the second piston 114 of the second cylinder chamber 132, and the third piston 151 of the third cylinder chamber 152. Is always in communication with the pressure surface A3 side of
The first fluid supply path is constituted by this and the circulation hole 121 of the first cylinder cover 111.

The second partition member 105 is provided with a vent hole 123 for communicating the rear surface B2 side of the second piston 114 of the second cylinder chamber 132 with the outside of the cylinder unit 100, and the second cylinder cover 112 is As in the first embodiment, there is a vent hole 133 for communicating the back surface B3 side of the third piston 151 of the third cylinder chamber 152 with the outside of the cylinder unit 100.

In FIG. 4, seals 128 and 129 are provided on the second partition member 105, and the piston ring 14
5 is attached to the third piston 151. The other structure is the same as that of the first embodiment, and the description thereof is omitted.

Next, the operation of the fluid cylinder of the second embodiment will be described. When the oil liquid from the hydraulic device 500 is supplied to the first circulation hole 121 of the first cylinder cover 111, the oil liquid becomes the first piston 1 of the first cylinder chamber 131.
13 to the pressure surface A1 side, and further to the piston 200
Through the communication hole 211 of the second cylinder chamber 132 into the pressurizing surface A2 side of the second piston 114 of the second cylinder chamber 132, and further from the hole 213 of the third piston 151 of the third cylinder chamber 152. It flows into the pressure surface A3 side and pushes the three pistons 113, 114, 151. At this time, the first, second and third pistons 1 are attached to the piston rod 200.
The combined output of the forces acting on 13, 114, 151 is given, and the piston rod 200 performs the output stroke.

During the return stroke, the first cylinder chamber 131
The oil liquid is supplied only to the back surface B1 side of the first piston 113 of the first piston 113, and the pressure stroke surface A1 side of the first piston 113 of the first cylinder chamber 131 and the second piston of the second cylinder chamber 132 in the output stroke. The oil liquid entering the pressurizing surface A2 side of 114 and the pressurizing surface A3 side of the third piston 151 of the third cylinder chamber 152 follows the original route to the hydraulic device 5.
00 oil tank 504.

In the second embodiment, the piston rod 200
In comparison with the conventional fluid cylinder having the same cylinder inner diameter, the output can be nearly tripled. Then, the return stroke is performed at least three times as fast as the output stroke.

Next, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, in the fluid cylinder of the second embodiment (FIG. 4), the first partition member 103 is connected to the third cylinder chamber 132 which is in communication with the second piston 114 on the pressurizing surface A2 side. A pipe 508 in which a circulation hole 321 is provided and the circulation hole is provided outside the cylinder unit 100.
Through the first circulation hole 121 of the first cylinder cover 111, and further communicates with the second partition member 105 on the pressurizing surface A3 side of the third piston 151 of the third cylinder chamber 152. A through hole 313 is provided, and the first through hole 121 and the third through hole 32 are provided via a pipe 507 and a pipe 508 provided outside the cylinder unit 100.
1 and the communication hole 211 of the second embodiment.
The first fluid supply path is configured except for the holes 212 and 213.

The other structure of the third embodiment is the same as that of the second embodiment, and the description thereof is omitted. Also, the third
The operation of the fluid cylinder according to this embodiment is the same as that of the second embodiment.

In the above-mentioned three embodiments, the example in which the cylinder chamber is divided into two or three is given, but the number of cylinder chambers may be four or more. Further, in the above-described embodiment, the cylinder chamber adjacent to the first cylinder cover is referred to as the first cylinder chamber, and the second fluid supply passage is provided on the back side of the first piston.
When there are two or more cylinder chambers, any cylinder chamber other than the cylinder chamber adjacent to the second cylinder cover can be used as the first cylinder chamber. That is, in the output stroke, the fluid pressure acts on the piston in each cylinder chamber, and in the return stroke, the pressure fluid may be supplied to the back side of the piston in only one cylinder chamber of the plurality of cylinder chambers.

[0035]

In the fluid cylinder according to the present invention, the pistons housed in each of the plurality of cylinder chambers are fixed to one piston rod, and the combined output of the forces acting on the plurality of pistons is applied to the piston rod. As compared with the conventional fluid cylinder with the same cylinder inner diameter,
A multiple value output corresponding to the number of cylinder chambers is obtained. Further, since the pressure fluid is supplied to the back surface of only one piston of one of the plurality of cylinder chambers so as to return the piston, there is an effect that the return stroke is faster than the output stroke.

At least one of the plurality of cylinder chambers is not supplied with pressure fluid to the rear surface side of its piston, so that the member facing the rear surface of the piston of the cylinder chamber is provided around the piston rod. <br/> stopping means is provided can Rukoto. Also, activate the limit switch.
The auxiliary rod having the dog for making the second cylinder cover
The second cylinder cover is fixed through the ventilation hole
The auxiliary rod can be moved in and out of the cylinder
Can be protected by In addition, the suspension for moving the auxiliary rod
A space for installing fluid cylinders without securing a pace.
Since the auxiliary rod can be moved if there is a space,
It is possible to use fluid cylinders with auxiliary rods
Yes, you can avoid interference between the auxiliary rod and other parts.
It

Furthermore, it is possible to use a compressed air device as the pressure fluid supply system instead of the hydraulic device.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment of a fluid cylinder according to the present invention, schematically showing a pressure fluid supply system.

FIG. 2 is a schematic diagram of a pressure fluid supply system when a fluid cylinder is caused to perform a return stroke.

3 is a cross-sectional view taken along line XX of FIG.

FIG. 4 is a vertical sectional view of a second embodiment of the fluid cylinder according to the present invention, schematically showing a pressure fluid supply system.

FIG. 5 is a longitudinal sectional view of a third embodiment of the fluid cylinder according to the present invention, schematically showing a pressure fluid supply system.

FIG. 6 is a vertical cross-sectional view showing a conventional fluid cylinder.

FIG. 7 is a vertical cross-sectional view showing another conventional fluid cylinder.

[Explanation of symbols]

 100 Cylinder Unit 101 First Cylinder Body 102 Second Cylinder Body 103 First Partition Member 104 Third Cylinder Body 105 Second Partition Member 111 First Cylinder Cover 112 Second Cylinder Cover 113 First Piston 114 Second Piston 131 First Cylinder Chamber 132 Second Cylinder Chamber 151 Third Piston 152 Third Cylinder Chamber 200 Piston Rod 232 Piston Rod Detent Member 500 Pressure Fluid Supply System

Claims (7)

[Claims] 1. A cylinder unit partitioned into a plurality of cylinder chambers in the axial direction by a partition member, and a first cylinder cover fixed to one end of the cylinder unit,
A second cylinder cover fixed to the other end of the cylinder unit, a piston rod slidably supported through the partition member and the second cylinder cover, and each cylinder of the plurality of cylinder chambers. A piston that is liquid-tightly and slidably housed in a chamber, has a pressing surface and a back surface, and is fixed to the piston rod,
A first fluid supply passage through which a pressure fluid flows in and out of a pressure surface of a piston of each of the cylinder chambers; and a first cylinder chamber of the plurality of cylinder chambers, which is the first cylinder.
A second fluid supply path for letting a pressure fluid flow in and out of the back side of the piston of the first cylinder chamber having a cover at one end, and the back side of the piston of each cylinder chamber other than the first cylinder chamber is the cylinder. A ventilation hole communicating with the outside of the unit, and the second cylinder cover of the piston rod.
Substantially the piston rod and the portion protruding from the bar
Installed so that they are parallel, create a limit switch.
An auxiliary rod having a dog for moving the
The cylinder cover 2 has the vent hole, and the auxiliary rod
Through the vent hole of the second cylinder cover
In the cylinder chamber where the second cylinder cover is fixed.
A fluid cylinder that can be moved in and out. 2. The first fluid supply passage is provided on the piston pressure surface side of the first cylinder chamber, and the first pressure fluid supply pipe and the piston pressure surface side of the first cylinder chamber are provided. And a communication hole that is provided in the piston rod and that communicates the pressurizing surface sides of the pistons of the plurality of cylinder chambers with each other, and the second fluid supply path is the first fluid communication path. 2. The fluid cylinder according to claim 1, comprising a second circulation hole that connects the back side of the piston of the cylinder chamber of the second pressure fluid supply pipe and the second pressure fluid supply pipe. 3. The first fluid supply passage is provided on the pressurizing surface side of the piston of the first cylinder chamber, and connects the first pressure fluid supply pipe and the pressurizing surface side of the first cylinder chamber. And a pipe that is provided outside the cylinder unit and that communicates the pressurizing surface side of the pistons of the plurality of cylinder chambers, and the second fluid supply path is the first cylinder. The fluid cylinder according to claim 1, comprising a second communication hole that connects the back side of the piston of the chamber and the second pressure fluid supply pipe. 4. The first circulation hole comprises the first silin.
The fluid cylinder according to claim 2 or 3, which is provided on the da cover . 5. The second circulation hole comprises the first silin.
It is provided on the partition member on the rear side of the piston in the chamber.
The fluid cylinder according to claim 4 , wherein 6. A rotation stopping means is provided on the piston rod.
The fluid cylinder according to claim 1 , which is a digit . 7. The detent means is the piston lock.
Flat portion formed on the side surface of the cylinder and the second cylinder cover.
It is provided on the bar and can slide on the flat surface of the piston rod.
7. The fluid cylinder according to claim 6, which comprises a detent member that abuts the movable cylinder.