JP7166606B2 - Cylinder device - Google Patents

Description

The present invention relates to a tandem cylinder device.

As this type of cylinder device, conventionally, there are those described in Patent Documents 1 and 2 below. The prior art is configured as follows.

In the pull-type clamp device disclosed in Patent Document 1, a fluid pressure passage communicating between the first and second unclamping fluid pressure working chambers is formed inside the piston rod. As a result, the fluid pressure supply system for supplying fluid pressure to the second unclamping fluid pressure actuation chamber is simplified and made compact.

The same applies to the clamping device disclosed in Patent Document 2, and a connecting passage for communicating two air chambers for unclamping is formed inside the clamp rod.

JP 2016-223473 A JP 2007-268625 A

The above prior art has the following problems.
In the above prior art, it is necessary to form a hole as a fluid pressure passage inside the piston rod (clamp rod), and this processing is troublesome.

SUMMARY OF THE INVENTION An object of the present invention is to provide a tandem-type cylinder device in which two release chambers are communicated without forming a hole inside the piston rod.

In order to achieve the above objects, the present invention, for example, as shown in FIGS. 1 to 3B, has a cylinder device configured as follows.

The cylinder device of the present invention comprises a housing 1, a first cylinder hole 4 formed in the housing 1, and a tubular first piston 6 inserted axially movably into the first cylinder hole 4. a first piston 6 having an annular first piston body 7 and a tubular guide 8 extending axially from the first piston body 7; and a second cylinder hole 5 formed in the housing 1. A second cylinder hole 5 formed on the tip side of the first cylinder hole 4, an annular second piston 9 inserted into the second cylinder hole 5 so as to be axially movable, A partition wall 12 is provided between the first cylinder hole 4 and the second cylinder hole 5, and is inserted into the cylinder hole 6a of the first piston 6 and the partition wall 12 into which the guide portion 8 is hermetically inserted. A flange portion 13a, which is a piston rod 13 that is hermetically inserted into the cylindrical hole 9a of the second piston 9 and that engages with the base end side portion of the first piston main body portion 7 in the axial direction, is provided. A piston rod 13 provided on the outer periphery, a first lock chamber 16 provided between the first piston body portion 7 and the partition wall 12, a second lock chamber 17 provided on the tip side of the second piston 9, A first release chamber 19 provided on the base end side of the first piston body portion 7 and the piston rod 13, and a second release chamber 20 provided between the partition wall 12 and the second piston 9. . Between the cylindrical hole 6 a of the first piston 6 and the outer peripheral surface of the piston rod 13 , a passage 14 is formed to allow the first release chamber 19 and the second release chamber 20 to communicate with each other.

The cylinder device of the present invention has the following effects.
A channel formed between the cylindrical hole of the first piston and the outer peripheral surface of the piston rod provides communication between the first release chamber and the second release chamber. Therefore, it is not necessary to form a hole for communicating the first release chamber and the second release chamber inside the piston rod, which facilitates machining of the piston rod.

In the above cylinder device of the present invention, it is preferable that the flow path 14 is an annular gap 14 between the tubular hole 6 a of the first piston 6 and the outer peripheral surface of the piston rod 13 .
Since the gap is formed by making the outer diameter of the piston rod slightly smaller than the diameter of the cylinder hole of the first piston, the piston rod can be easily machined.

Further, in the above cylinder device of the present invention, the second piston 9 includes an annular second piston body portion 10 and an annular convex portion 11 having an outer diameter smaller than that of the second piston body portion 10, It is preferable to have a convex portion 11 that abuts on the tip portion of the guide portion 8 .
With this configuration, the weight of the second piston is reduced compared to the case where the annular second piston has a constant thickness in the axial direction, including the convex portion. Therefore, the movement of the second piston to the tip side becomes rapid during the release drive. As a result, the pressurized fluid can be quickly made to flow from the second release chamber into the first release chamber, thereby allowing the piston rod to be quickly advanced to the distal end side.

Preferably, the cylinder device of the present invention further includes the following configuration.
A piston rod turning mechanism 22 is provided on the base end side of the flange portion 13a.
With this configuration, the piston rod can be turned.

ADVANTAGE OF THE INVENTION According to this invention, the tandem type cylinder apparatus of the structure which made two release chambers communicate without making the hole in the inside of a piston rod can be provided.

FIG. 1 shows an embodiment of the present invention, and is a cross-sectional view of a cylinder device in a released state as viewed in elevation. FIG. 2 is a cross-sectional elevational view of the cylinder device in a locked state. FIG. 3A is a cross-sectional elevational view of the cylinder device in an initial state in the middle of switching from the locked state to the released state. FIG. 3B is a cross-sectional elevational view of the cylinder device in an intermediate state in the middle of switching from the locked state to the released state.

1-3B illustrate one embodiment of the present invention.
This embodiment illustrates a case where the cylinder device of the present invention is applied to a swivel clamp device. A configuration of a cylinder device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3B.

A housing 1 is attached to a fixed base T such as a table. The housing 1 has a housing main body 2 and a bottomed cylindrical lower end wall 3 fixed to the lower end of the housing main body 2 . A first cylinder hole 4 is formed in the lower portion of the housing body 2 , and a second cylinder hole 5 is formed above the first cylinder hole 4 (front end side).

A cylindrical first piston 6 is hermetically inserted into the first cylinder hole 4 so as to be movable in the vertical direction (axial direction). The first piston 6 has an annular first piston main body portion 7 and a tubular guide portion 8 extending upward (toward the tip side) from the first piston main body portion 7 . An annular second piston 9 is hermetically inserted into the second cylinder hole 5 above the first piston 6 so as to be movable in the vertical direction (axial direction). The second piston 9 has an annular second piston body portion 10 and an annular convex portion 11 having an outer diameter smaller than that of the second piston body portion 10 . The convex portion 11 abuts on the tip portion of the guide portion 8 .

A partition wall 12 is provided between the first cylinder hole 4 and the second cylinder hole 5, and the guide portion 8 of the first piston 6 is hermetically inserted into the partition wall 12. As shown in FIG. The partition wall 12 is fixed to the housing body 2 with a retaining ring 27 .

A piston rod 13 is inserted into the tubular hole 6 a of the first piston 6 and the tubular hole 9 a of the second piston 9 . The outer diameter of the insertion portion of the piston rod 13 is set to be slightly smaller than the diameter of the cylindrical hole 6a of the first piston 6, so that the space between the cylindrical hole 6a of the first piston 6 and the outer peripheral surface of the piston rod 13 A gap 14 is formed as a flow path in the . A piston rod 13 is hermetically inserted into the tubular hole 9a of the second piston 9 . A flange portion 13a is formed on the outer periphery of the piston rod 13 so as to axially engage with the base end portion of the first piston body portion 7. As shown in FIG.

The tip side portion of the piston rod 13 is tapered, and this tapered portion is fitted into a hole 28a formed at the end of the clamp arm 28 and fixed with a nut 29. As shown in FIG. A lower end portion of the piston rod 13 is inserted into a support hole 3 a formed in a lower end wall 3 of the housing 1 .

A first lock chamber 16 for moving the first piston 6 downward (base end side) is provided between the first piston main body 7 and the partition wall 12, and moves the second piston 9 downward (base end side). ) is provided above (front end side) of the second piston 9 . Pressurized oil as pressure fluid for locking is supplied to and discharged from the first lock chamber 16 and the second lock chamber 17 through a common lock port 18 . The illustration of a supply and discharge passage for pressure oil to the lock port 18 is omitted.

In addition, a first release chamber 19 for moving the first piston 6 and the piston rod 13 upward (toward the distal end) is provided below (toward the proximal end) the first piston main body 7 and the piston rod 13, A second release chamber 20 for moving the second piston 9 upward (front end side) is provided between the partition wall 12 and the second piston 9 . The first release chamber 19 has a distal release chamber 19a provided between the first piston body 7 and the lower end wall 3, and a proximal release chamber 19b provided within the support hole 3a. The distal release chamber 19a and the proximal release chamber 19b communicate with each other.

Pressure oil as pressure fluid for release is supplied to and discharged from the second release chamber 20 through the release passage 21 . Note that illustration of a release port that communicates with the release passage 21 is omitted. Although details will be described later, since the first release chamber 19 and the second release chamber 20 are communicated with each other through the gap 14, the pressure oil supplied to the second release chamber 20 passes through the gap 14 and flows into the first release chamber. 19 (distal side release chamber 19a).

A piston rod turning mechanism 22 is provided on the base end side of the flange portion 13 a of the piston rod 13 , that is, on the lower end portion of the piston rod 13 . The piston rod turning mechanism 22 is constructed as follows.

At least one guide groove 23 is formed on the outer peripheral surface of the lower end portion of the piston rod 13. The guide groove 23 includes a linear groove 23a and a spiral turning groove 23b which are vertically connected. At least one horizontal hole 24 is formed in the upper part of the peripheral wall of the support hole 3a, and a ball 25 inserted into this horizontal hole 24 is fitted in the guide groove 23. As shown in FIG. A ring 26 is rotatably fitted around the outer circumference of the ball 25 .

The cylinder device having the above configuration operates as follows.
In the released state shown in FIG. 1 , pressure oil is discharged from the first lock chamber 16 and the second lock chamber 17 and pressure oil is supplied to the first release chamber 19 and the second release chamber 20 .

When switching from the released state shown in FIG. 1 to the locked state shown in FIG. 2, pressure oil is supplied from the lock port 18 to the first lock chamber 16 and the second lock chamber 17 . Then, the pressure oil in the second lock chamber 17 causes the second piston 9 to push the piston rod 13 downward via the first piston 6 , and the pressure oil in the first lock chamber 16 causes the first piston 6 to push the piston rod 13 . Push downwards. Thereby, the piston rod 13 descends. Here, the piston rod 13 descends while rotating clockwise by the piston rod rotating mechanism 22, and then descends straight. As the piston rod 13 descends, the tip of the clamp arm 28 presses the object W to be clamped from above, as shown in FIG. As a result, the piston rod 13 stops descending and becomes locked.

When switching from the locked state shown in FIG. 2 to the released state shown in FIG. 1, pressure oil is supplied from the release passage 21 to the second release chamber 20 . Then, as shown in FIG. 3A, the pressure oil in the second release chamber 20 causes the second piston 9 to rise. Next, as shown in FIG. 3B, the fuel flows from the second release chamber 20 into the first release chamber 19 through the gap 14 formed between the cylindrical hole 6a of the first piston 6 and the outer peripheral surface of the piston rod 13. The pressure oil causes the first piston 6 to rise. After that, as shown in FIG. 1, the piston rod 13 is lifted by the pressurized oil in the first release chamber 19 (base-side release chamber 19b). The piston rod 13 first rises straight by the piston rod turning mechanism 22, and then rises while turning counterclockwise. As the piston rod 13 rises, the flange 13a of the piston rod 13 comes into contact with the first piston main body 7, as shown in FIG. As a result, the upward movement of the piston rod 13 is stopped and a released state is established.

The movement of the first piston 6 and the second piston 9 to the release side is free, and the first piston 6 and the second piston 9 are engaged with the piston rod 13 during the release drive to switch from the locked state to the released state. rise without Therefore, the first piston 6, the second piston 9, and the piston rod 13 are not loaded with each other during the release drive.

The above embodiment can be modified as follows.
In the cylinder device described above, the piston rod 13 is inserted into the cylindrical hole 6a of the first piston 6 with a predetermined gap 14 therebetween, thereby forming a flow path for communicating the first release chamber 19 and the second release chamber 20. formed. Alternatively, an axially extending groove may be formed in the surface of the piston rod 13 as a flow path for communicating the first release chamber 19 and the second release chamber 20 . It is easier to machine the piston rod by forming grooves on the surface of the piston rod than by making holes inside the piston rod.

The pressurized fluid for locking and releasing may be compressed gas such as compressed air or compressed nitrogen gas instead of pressurized oil.

The cylinder device of the present invention is not limited to a swivel type clamp device, and may be other types of clamp devices such as a clamp device in which the piston rod does not swivel. Furthermore, it is not limited to a clamping device, and may be a reciprocating device for advancing and retreating an object.

The embodiments and modifications of the present invention have been described above. In addition, it is of course possible to make various modifications within the range that a person skilled in the art can assume.

1: housing, 4: first cylinder hole, 5: second cylinder hole, 6: first piston, 6a: cylinder hole, 7: first piston main body, 8: guide part, 9: second piston, 9a: Cylindrical hole 10: second piston main body 11: convex portion 12: partition wall 13: piston rod 13a: collar portion 14: gap (flow path) 16: first lock chamber 17: second lock chamber, 19: first release chamber, 20: second release chamber, 22: piston rod turning mechanism

Claims (4)

a housing (1);
a first cylinder hole (4) formed in the housing (1);
A cylindrical first piston (6) inserted movably in the first cylinder hole (4) in the axial direction, comprising an annular first piston main body (7) and the first piston main body (7) ), a first piston (6) having a tubular guide portion (8) extending axially from
a second cylinder hole (5) formed in the housing (1), the second cylinder hole (5) being formed on the tip side of the first cylinder hole (4);
an annular second piston (9) axially movably inserted into the second cylinder hole (5);
a partition wall (12) provided between the first cylinder hole (4) and the second cylinder hole (5), the partition wall (12) into which the guide part (8) is hermetically inserted; ,
A piston rod (13) inserted into a cylindrical hole (6a) of the first piston (6) and hermetically inserted into a cylindrical hole (9a) of the second piston (9), 1 a piston rod (13) having a flange (13a) on its outer circumference that engages with the base end portion of the piston main body (7) in the axial direction;
a first lock chamber (16) provided between the first piston body (7) and the partition wall (12);
a second lock chamber (17) provided on the tip side of the second piston (9);
a first release chamber (19) provided on the proximal end side of the first piston body (7) and the piston rod (13);
a second release chamber (20) provided between the partition (12) and the second piston (9);
with
The piston rod (13) is hermetically inserted into the cylindrical hole (9a) of the second piston (9) at a portion closer to the tip than the flange (13a),
A flow that communicates the first release chamber (19) and the second release chamber (20) between the cylindrical hole (6a) of the first piston (6) and the outer peripheral surface of the piston rod (13). a path (14) is formed;
cylinder device. In the cylinder device of claim 1,
The flow path (14) is an annular gap (14) between the cylindrical hole (6a) of the first piston (6) and the outer peripheral surface of the piston rod (13).
cylinder device. In the cylinder device according to claim 1 or 2,
The second piston (9) is
an annular second piston body (10);
An annular convex portion (11) having an outer diameter smaller than that of the second piston body portion (10), the convex portion (11) coming into contact with the tip portion of the guide portion (8),
cylinder device. In the cylinder device according to any one of claims 1 to 3,
A piston rod turning mechanism (22) is provided on the base end side of the collar (13a),
cylinder device.

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