JPS62804Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a double-acting cylinder with a control valve for operating a chuck, a gripping claw of a clamp device, etc.

In conventional double-acting cylinders of this type, the valve body of the check valve is fitted into the valve storage chamber in the cylinder body so as to be slidable by a predetermined amount, and a spring is inserted into the valve body against the valve seat. When two valve bodies pressed together are arranged symmetrically and pressurized fluid is supplied from one pressure fluid supply port, this pressure fluid slides the valve body and opens the return side valve body, and the supply side valve The valve body is pushed open against a spring to operate the piston, so when the valve body is pushed open and pressurized fluid is supplied, the valve body vibrates and generates noise, and the supply of pressurized fluid also increases. In addition, since the valve body houses a spring in addition to the valve body, the length of the valve body increases accordingly, and there is also the problem that accidents due to breakage of the spring are likely to occur. It was hot. Furthermore, since the valve body on the return side is opened by sliding the valve body, there is a problem in that there are many sealing points in the sliding portion.

Therefore, the purpose of this invention is to solve each of the above problems, and when pressure fluid is supplied from one pressure fluid supply port, the pressure fluid on the back pressure side flows out without sliding the valve body, and the piston slides. The object of the present invention is to provide a double-acting cylinder with a control valve that can be operated to move the piston and, when the supply of pressurized fluid is finished, prevent the outflow of the pressurized fluid supplied into the piston chamber without using a spring. be.

1 to 3 show a first embodiment of the present invention, which is implemented in a rotary cylinder attached to the rear surface of a spindle of a machine tool for operating a chuck pawl. In these drawings, 1 is a cylinder body, which is composed of a cylinder member 2 and a lid member 3 fixed to this cylinder member 2. This cylinder body 1 is normally fixedly attached to the rear surface of a spindle of a machine tool such as a lathe (not shown), and is configured to rotate integrally with the spindle. 4 is a piston rod inserted into the center of the cylinder member 2 and the lid member 3 so as to be slidable in the axial direction, and a connecting rod (not shown) for operating the claw of the chuck can be connected to the front end thereof. It's summery. 5 is a piston chamber 6 of the cylinder body 1
A piston is slidably fitted in the piston rod 4 and is fixed to the piston rod 4 by a mounting nut 7. Reference numeral 8 denotes a distributor, which is composed of a fixed member 10 and a rotating shaft member 11 rotatably fitted in the center of the fixed member 10. This rotating shaft member 11
is composed of a shaft member 12 and an auxiliary member 13, and this shaft member 12 is fixed to the rear end of the piston rod 4. The fixing member 10 is provided with two pressure fluid supply ports 14 and 15, and is configured to be prevented from rotating by a guide (not shown) when in use. Next, the piston rod 4
A valve storage chamber 17 is formed inside the valve storage chamber 17 by an axial storage hole 16 formed at the center of rotation and the auxiliary member 13 fitted into the end of the storage hole 16. A control valve 18 is fixedly fitted therein. This control valve 18 is constructed as shown in FIG. In this control valve 18, 19 is a valve body fixed in the valve storage chamber 17, and in the drawing, it is composed of two members, a first valve body 19a and a second valve body 19b. This valve body 1
9 has three O-rings 20a, 20b, 2
0c is fitted, and the gap with the inner surface of the valve housing hole 16 is closed. An operating piston chamber 21 is formed in the center of the valve body 19, and control piston chambers 2 are formed on both sides of the operating piston chamber 21.
2 and 23 are formed so as to be continuous with the operation piston chamber 21, respectively. An operating piston 24 is fitted into the operating piston chamber 21 so as to be slidable by a predetermined amount. Control pistons 26 and 27 are slidably fitted in the control piston chambers 22 and 23, respectively. These control pistons 26, 27
is related to the operating piston 24 so that the control piston 26 or 27 on the sliding direction side is pressed and moved by sliding of the operating piston 24 to one side, and in the drawing, the side surface of the operating piston 24 is directly controlled. The inner end of the piston 26 or 27 is pushed, but the operating piston 24 or the control piston 2
It may also be pushed through pins etc. attached to 6 and 27. Reference numerals 28 to 30 indicate O-rings fitted to the sliding portions of the operating piston 24 and control pistons 26 and 27. The valve body 19 has supply holes 33 and 34 which connect both sides of the operation piston chamber 21 to pressurized fluid supply passages 31 and 32 formed in the piston rod 4, respectively, and operation pistons in the control piston chambers 22 and 23. 24 side is connected to both sides of the piston chamber 6 through communication passages 3, respectively.
5, 36 to communicate with each other through the discharge hole 3.
7 and 38 are formed, respectively. The pressure fluid supply passages 31 and 32 are communicated with the pressure fluid supply ports 14 and 15 of the fixed member 10 via communication passages 39 and 40 provided in the rotating shaft member 11 of the distributor 8, respectively. The control pistons 26, 27 have a smaller diameter than the discharge holes 37, 38, and when the control pistons 26, 27 are slid toward the side opposite to the operation piston 24, the side portions of the control pistons 26, 27 are That is, a valve hole 41 is configured to allow the supply holes 33, 34 and the discharge holes 37, 38 to communicate with each other, and to cut off the communication when the valve is slid toward the operating piston 24.
42 are formed respectively.

In the double-acting cylinder with a control valve configured as described above, when air (compressed air) as a pressure fluid is supplied from one pressure fluid supply port 14, this air flows through the communication passage 39, the pressure fluid supply passage 31, and the supply It flows through the hole 33 into one side of the operating piston chamber 21 (the right side in the drawing) and the operating piston 24
as shown in FIG. 2, and the right control piston 26 is also slid to the right.
When the operating piston 24 is slid to the left in this way, the operating piston 24 pushes the left control piston 27 and slides in the same direction, causing the operating piston 24 to slide a predetermined amount as shown in FIG. When the piston 27 is moved and reaches the end of its stroke, the valve hole 42 of the control piston 27 is disengaged from the sliding portion, allowing both side portions of the control piston 27 to communicate with each other. Therefore, the left supply hole 34 and the left discharge hole 38 are communicated with each other, and the air in the left side portion (back pressure side portion) of the piston chamber 6 can flow out from the other pressure fluid supply port 15. On the other hand, when the right control piston 26 is slid to the right and reaches its stroke end, the valve hole 41 of the right control piston 26 is disengaged from the sliding portion, allowing both sides of the control piston 26 to communicate with each other. As a result, the supply hole 33 on the right side and the discharge hole 37 on the right side are communicated, and the air flows into the right side portion of the piston chamber 6 through the communication passage 35, causing the piston 5 to move leftward while causing the air in the back pressure side portion to flow out. Slide it to. This sliding movement of the piston 5 causes the piston rod 4 to slide integrally to operate claws such as chucks, thereby causing these claws to grip the workpiece. When sliding the piston 5 as described above, the valve holes 41 and 4 of the control pistons 26 and 27
2 is held fully open and these valve holes 4
Since air can be smoothly supplied and discharged from 1 and 42,
The piston 5 can be slid quickly. Next, when the supply of air from the pressure fluid supply port 14 is terminated and the pressure fluid supply port 14 is communicated with the atmosphere, the air that has flowed into the right side of the cylinder chamber 6 as described above is transferred to the control piston. It attempts to flow out through the valve hole 41 of 26. However, since the valve hole 41 is set to have a smaller diameter than the discharge hole 37, the air pressure on the discharge hole 37 side (right side) of the control piston 26 becomes higher than the air pressure on the supply hole 33 side (left side). The control piston 26 is quickly slid toward the operating piston 24 (left side) as shown in FIG. 3, thereby closing the valve hole 41 and cutting off communication between the supply hole 33 and the discharge hole 37. Therefore, the outflow of the air supplied to the right side of the cylinder chamber 6 is blocked almost simultaneously with the end of the air supply, and the piston 5 and piston rod 4 are reliably held in their original positions, and the workpiece is removed by the chuck's claw. The grip state is maintained. Next, when air is supplied to the other pressure fluid supply port 15, the operating piston 2
4 and the right-hand control piston 26 to the right, thereby supplying air into the left-hand portion of the piston chamber 6 and causing the piston 5 to slide to the right while causing air in the right-hand portion to flow out. Therefore, the piston rod 4 is moved rightward to open the chuck pawl.

FIG. 4 shows a case in which the present invention is applied to a front chuck, where the chuck body 50 constitutes the cylinder body of a double-acting cylinder. In this front chuck, the chuck body 50 has an annular inner body 51 having a large diameter portion 51a and a small diameter portion 51b, and an annular outer body 52 having a large diameter portion 52a and a small diameter hole 52b. They are combined to form a The above piston chamber 6
An annular piston 5e is slidably fitted into the inside of the annular piston 5e, and a part of the annular piston 5e is connected to the small diameter portion 5.
It is slidably fitted into the annular space between the outer periphery of the small diameter hole 1b and the inner periphery of the small diameter hole 52b. Further, a draw bar 54 for sliding the chuck pawl 53 in the radial direction is connected to the front surface of the annular piston 5e, and when the draw bar 54 is slid, the chuck pawl 53 is slid using a wedge groove or the like. It's like that. A valve storage hole 16e is formed in the front surface of the chuck main body 50, and a valve storage chamber 1 is formed in the chuck main body 50 by screwing a plug 55 into the valve storage hole 16e.
7e is formed. A control valve 18e having the same configuration as the embodiment described above is fixedly fitted in the valve storage chamber 17e. The two supply holes of this control valve 18e are connected to the pressure fluid supply passage 31 in the chuck body 50.
e, 32e to the pressure fluid supply ports 14e, 15e of the pressure fluid supply ring 56, and the two discharge holes are connected to both sides of the cylinder chamber 6e via the communication passages 35e, 36e and the communication hole 57 of the annular piston 5e. The parts are connected to each other. In this embodiment as well, one pressure fluid supply port 1 is similar to the above embodiment.
When air is supplied to the piston 4e, the annular piston 5e slides to the left, and when the air supply is terminated, the air supplied to the right side of the piston chamber 6e is prevented from flowing out. Also, the other pressure fluid supply port 15e
When air is supplied to the annular piston 5e, the annular piston 5e can be slid to the right. In this embodiment, parts that can be considered to be the same or equivalent as those in the above embodiment are given the same reference numerals as in the above embodiment with an alpha e, and redundant explanation is omitted.

Note that the present application is not limited to the above embodiments, and may include a rotary cylinder in which the rotating shaft portion of the distributor is fixed to the cylinder body, a control valve built in the cylinder body, or a general fixed cylinder. A control valve may be built into the cylinder body.

As described above, in the present invention, when pressurized fluid is supplied from one pressurized fluid supply port, this pressurized fluid slides the operating piston to one side and slides one control piston to the outer end side. At the same time, the other control piston is slid toward the outer end.
By supplying pressurized fluid from one of the pressurized fluid supply ports, the pressurized fluid can be supplied to the supply side of the piston chamber while discharging the pressurized fluid from the back pressure side of the piston chamber, which had been blocked from flowing out. The reciprocating movement of the piston can be performed with a simple operation like a general cylinder. Furthermore, when the supply of pressure fluid from one pressure fluid supply port is finished, the control piston on the pressure fluid supply side is slid toward the operating piston side and the valve hole is closed, so that the supply side portion of the piston chamber is closed. It is possible to stop the flow of the pressurized fluid supplied to the piston, thereby safely maintaining the piston and piston rod in the operating position as if mechanically locked. Furthermore, even if the control piston is configured to slide toward the operating piston side when the supply of pressurized fluid is finished as described above to prevent the pressure fluid from flowing out of the piston chamber, the control piston is slid toward the operating piston side. The sliding movement is not done by a spring, but by using the pressure of the pressurized fluid supplied into the piston chamber.
The sliding movement of the control piston toward the operating piston can be performed over a long period of time with fewer failures, and the length of the valve body can be made relatively short, which has the advantage of being easily incorporated into small double-acting cylinders. be.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, and FIG. 1 is a sectional view showing an example implemented in a rotating cylinder, FIG. 2 is an enlarged sectional view of a control valve, and FIG. 3 is an enlarged sectional view showing the operating state of the control valve. 4 are sectional views showing an example implemented in a front chuck. 1... Cylinder body, 4... Piston rod,
6...Piston chamber, 17...Valve storage chamber, 18...
Control valve, 19... Valve body, 21... Operating piston chamber, 22, 23... Control piston chamber, 24... Operating piston, 26, 27... Control piston, 3
1, 32... Pressure fluid supply passage, 33, 34... Supply hole, 37, 38... Discharge hole, 41, 42... Valve hole.

Claims (1)

[Scope of utility model registration request] The valve body of the control valve is fixedly fitted into a valve storage chamber formed in the cylinder body or piston rod,
An operating piston chamber and a control piston chamber continuous to both sides of the operating piston chamber are formed in the valve body, and the operating piston is slidably slidable in the operating piston chamber, and the control piston is slidably slidable in the control piston chamber. fitting the control piston and the operating piston so that sliding of the operating piston toward one side presses and moves the control piston on the sliding direction side;
The valve body also has supply holes that connect both sides of the operating piston chamber to the pressure fluid supply passages of the cylinder body or piston rod, and supply holes that communicate the opposite side of the control piston chamber from the operating piston side to both sides of the piston chamber. The control piston is further provided with a valve hole that is smaller than the discharge hole so that the control piston has a valve hole that communicates with both sides of the control piston when the control piston is slid toward the side opposite to the operating piston. A double-acting cylinder with a control valve, which is formed so as to communicate with each other, but to cut off the communication when slid toward the operating piston.