JP2001050213A - Hydraulic cylinder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic cylinder device having a built-in stopping mechanism for safe and surely stopping, and compact appearance. SOLUTION: This hydraulic cylinder comprises a cylinder 1, a cylinder rod 2 arranged in the cylinder 1 as freely projecting and sinking and provided with a piston part 6 dividing inside the cylinder 1 into a pressure chamber 4 and a recovery chamber 5, and a high speed projection operating chamber 7, a hollow pipe 9 for oil flow inserted from a closed end 8 of the cylinder 1 into the operation chamber 7 of the cylinder rod 2 and having a stopper 10 formed at its end, and a movable valve 12 moving along the hollow pipe 9 and continuously pressed and energized in the direction of the stopper 10, engaging with an engaging part 11 in the cylinder rod 2 when abutting on the stopper 10, after engagement with the stopper 10 moving from the engaging part 11 in the apart direction for communicating the pressure chamber 4 and the operating chamber 7 and releasing the oil pressure of the pressure chamber 4 via the hollow pipe 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel hydraulic cylinder device in which an overrun prevention mechanism for a cylinder rod is incorporated.

[0002]

2. Description of the Related Art FIG. 7 shows a conventional high-speed hydraulic cylinder device (B).
FIG. In the figure, a cylinder rod (42) is provided so as to freely protrude and retract into a cylinder (41), and the interior of the cylinder (41) is separated from the pressurizing chamber (44) by a piston portion (46) of the cylinder rod (42). It is divided into a return room (45). Furthermore, a high-speed projecting working chamber (4
7) is formed, and a hollow pipe is inserted from the closed end (48) of the cylinder (41) into the high-speed projecting working chamber (47) of the cylinder rod (42).
(49) is inserted.

Guide rods (51) are respectively attached to a plurality of guide attachment portions (53) attached to the protruding ends of the cylinder rod (42), and are integrally provided on the outer surface of the cylinder (41). Guide holes (52) formed in a plurality of guides (52)
a) is inserted to slide. Guide rod (51)
A stroke adjustment bar (54) is attached to the other end of the stroke adjustment bar (54).
5) is installed.

The operation of the conventional high-speed hydraulic cylinder device (B) formed as described above will be briefly described. In the case where the cylinder rod (42) projects from a state of being immersed in the cylinder (41). First, pressure oil is supplied into the high-speed projecting working chamber (47) through the hollow pipe (49). High-speed protrusion working chamber (47)
Is small, whereby the cylinder rod (42) is quickly pushed out of the cylinder (41).

When the cylinder rod (42) reaches just before the workpiece processing position, the supply of oil to the hollow pipe (49) is stopped by a limit switch (not shown), and the supply of oil to the pressurizing chamber (44) is switched. As a result, since the pressurizing chamber (44) has a larger area than the high-speed projecting working chamber (47), the cylinder rod
(42) is slow, but is pushed out further with high output. As a result, the punch attached to the tip of the cylinder rod (42) performs, for example, hole formation by punching.

[0006] The cylinder rod (42) is not pushed out indefinitely, but it is necessary to stop the piston portion (46) before the piston portion (46) comes into contact with the open end (43) of the cylinder (41) when the hole machining of the work is completed. is there. At high pressure, the piston (46)
When it comes into contact with the opening end (43) of (1), the sealing member provided at the opening end (43) is broken, causing oil leakage, which leads to damage of the high-speed hydraulic cylinder device (B).

For this purpose, the stroke of the cylinder rod (42) is adjusted by the stroke adjusting screw (55). That is, before the piston portion (46) comes into contact with the open end (43), the tip of the stroke adjusting screw (55) is closed by the closed end (4) of the cylinder (41).
8) to restrict the protrusion of the cylinder rod (42).

In such a case, robust guide rods (51) are provided on both sides of the cylinder (41) so as to withstand the protrusion of the cylinder rod (42) under high pressure, and furthermore, above the closed end (48). The stroke adjustment bar (54) and the stroke adjustment screw (55) attached to it must be provided, and the stroke adjustment mechanism itself becomes very large, and as a result, the overall shape of the high-speed hydraulic cylinder device (B) becomes large. Not only is it taller, it also looks ugly. Also, if there is an error in the adjustment amount by the stroke adjustment screw (55), the piston (46) abuts on the open end (43) of the cylinder (41) before the stop by the stroke adjustment screw (55) is applied. There was also a problem that the high-speed hydraulic cylinder device (B) was damaged.

[0009]

The problem to be solved by the present invention is as follows.
Eliminating the stroke adjustment mechanism that appears outside, such as the stroke adjustment bar, stroke adjustment screw, and guide rod as described above, allows the same stroke adjustment function to be built into the device and makes its appearance smarter. Therefore, it is an object of the present invention to develop a hydraulic cylinder device capable of making the stopping operation safe and secure.

[0010]

According to a first aspect of the present invention, there is provided a hydraulic cylinder device (A) comprising a cylinder rod (3) extending from an open end (3).
The cylinder (1) in which (2) protrudes and retracts and the cylinder (1) are disposed so as to freely protrude and retract, and divides the inside of the cylinder (1) into a pressurizing chamber (4) and a return chamber (5). A hollow cylinder rod (2) having a piston section (6) and a high-speed projecting working chamber (7) formed therein, and a high-speed cylinder rod (2) from the closed end (8) of the cylinder (1) A hollow pipe (9) for pressurized oil supply and discharge, which is inserted into the protruding working chamber (7) and has a stopper (10) at its end, and is disposed in a hollow cylinder rod (2). Movably mounted along the hollow pipe (9), and the stopper (1
In the direction of 0), it is always urged and pressed, and before engaging with the stopper (10), it engages with the engaging portion (11) in the hollow cylinder rod (2) and engages with the stopper (10). Thereafter, the pressure chamber (4) moves in a direction away from the engagement portion (11) to communicate the pressurizing chamber (4) with the high-speed projecting operating chamber (7), and the pressure of the pressurizing chamber (4) is reduced through a hollow pipe (9). And a movable valve (12) for releasing oil. "

According to this, when the movable rod (12) engaged with the stopper (10) moves the cylinder rod (2) by a predetermined stroke (X + Z), the pressurizing chamber (4) is inevitably. The hydraulic oil in the cylinder escapes to the high-speed protruding working chamber (7) and stops.Therefore, there is no malfunction and the cylinder rod (2) can be securely moved within the total stroke range (Y) of the hydraulic cylinder device (A). It can be stopped and will not damage the hydraulic cylinder device (A).

A second aspect of the present invention is the hydraulic cylinder device described above.
Improvement of (A) `` When the pressurizing chamber (4) communicates with the high-speed protruding working chamber (7), the pressurizing chamber (4) communicates with the pressurizing chamber (4) and the high-speed protruding working chamber (7). Communication part (17) and communication part on the high-speed projecting working chamber (7) side
At least one of (18) is formed so as to gradually increase its communication area when overlapping. "

According to this, when the communicating portions (17) and (18) overlap each other, the communicating area is formed so as to gradually increase, so that the cylinder rod (2) stops gradually and stops. The shock of time can be eliminated. Although the gradually increasing portion (26) of the communication area may have any shape,
For example, a triangular pyramid-shaped groove as shown in FIG. Also,
In the present embodiment, each of the communication portions (17) and (18) is formed by a “groove”, but is not limited to this, and may be a combination of a “groove” and a “hole”.

The third aspect is the hydraulic cylinder device (A).
Further improvement of `` stopper (10) for hollow pipe (9)
The fixed position of is variable. " By doing so, the stop position of the cylinder rod can be freely changed.

[0015] Claim 4 is a further limitation of the hydraulic cylinder device (A) according to any one of claims 1 to 3, wherein "the closed end (8) of the cylinder (1) constituting the pressurizing chamber (4)". ), On the opposing surface of the piston portion (6) opposing the closed end (8), a pressurizing chamber (4)
Ring part (27) that forms pressure oil occlusion space (31) when contracted
And a blocking protrusion (28) fitted into the pressure oil blocking space (31).
(31) A flow regulating valve (32b) for gradually releasing the pressure oil in the outside to the outside is installed in communication with the pressure oil closed space (31). "

By doing so, the cylinder rod (2)
At the final stage of the return, the closing protrusion (28) fits into the ring portion (27) to form a pressure oil closing space (31), and the pressure oil is confined in this space to become a resistance. And the flow control valve (3
Since the pressure oil in the pressure oil blockage space (31) is gradually released to the outside by 2b), the return speed of the cylinder rod (2) decreases in the final stage of return. Thereby, the stop shock at the time of return of the cylinder rod (2) is reduced.

A fifth aspect of the present invention relates to a further limitation of the hydraulic cylinder device (A) according to the fourth aspect, wherein "the inner peripheral edge of the ring portion (27) and the closing protruding portion (28) fitted into the inner edge of the ring portion (27)". A communication area adjusting portion (30) is formed which reduces the communication area between the inside and outside of the pressure oil occlusion space (31) as the occlusion protrusion (28) fits into at least one of the outer peripheral edges. '' And

In this case, the closing projection (28) is attached to the ring (27).
Since the communication area adjusting portion (30) for reducing the communication area between the inside and the outside of the pressure oil closed space (31) is formed when the fitting is performed, the inside and outside communication area gradually decreases as the fitting operation proceeds. Therefore, the resistance will gradually increase. As a result, the shock at the start of the fitting operation is killed, and the operation of returning the cylinder rod (2) is stopped very smoothly.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. Conventional example and the hydraulic cylinder device of the present invention (A) (B)
Are used as driving sources for various machines, and are used by attaching a punch or a mold to the protruding end of the cylinder rod (2), and include, for example, a punching device or a press forming device. Can be In FIG. 1, a hollow cylinder rod (2) is provided inside a cylinder (1).
Are arranged so that they can protrude and retract, and the cylinder rod
The inside of the cylinder (1) is divided into a pressurizing chamber (4) and a return chamber (5) by a piston portion (6) formed on the outer periphery of the immersion end of (2).

In the pressurizing chamber (4), the inner surface of the closed end (8) of the cylinder (1) (that is, the ceiling portion of the pressurizing chamber (4))
A ring (27) is formed to form a pressurized oil blockage space (31) when the pressurizing chamber (4) is reduced, and the piston (6) faces the inner surface of the block end (8) of the cylinder (1). Is formed with a closing protruding portion (28) that fits in the opposing portion of. And a small hole (29) for the shock absorber communicating with the pressure oil blockage space (31)
Are formed in the ring portion (27). The ring part
It goes without saying that the position of (27) and the closing protrusion (28) may be reversed, in which case the small hole (29) will be formed through the closing protrusion (28). .

The small hole (29) is provided with a flow regulating valve (32b) for gradually releasing the pressure oil in the pressure oil closed space (31) to the outside when the pressure oil closed space (31) is reduced. Has been installed,
A check valve (32a) is provided in parallel with this.

The closing protrusion (28) fits into the ring portion (27) at least one of the inner peripheral edge of the ring portion (27) and the outer peripheral edge of the closing protrusion (28) fitted therein. A communication area adjusting section (30) for reducing the communication area between the inside and outside of the pressure oil closed space (31) according to the above is formed. Communication area adjustment unit (3
(0) may be a triangular pyramid-shaped groove or another shape, but in the present embodiment, the outer peripheral edge of the closing protrusion (28) is chamfered in a tapered shape, and this portion is used as a communication area adjusting portion (30). . Conversely, the inner peripheral edge of the ring portion (27) may be chamfered, and this portion may be used as the communication area adjusting portion (30).

The cylinder rod (2) is hollow and has a high-speed protruding working chamber (7) formed therein. In the high-speed protruding working chamber (7), a fixed valve (15) constituting a part of the cylinder rod (2) is provided. ) Is stored
Fixed. The fixed valve (15) is a cylindrical body with a bottom and is open on the side of the high-speed protruding working chamber (7), and an engaging portion (11) protrudes from an open end on the side of the high-speed protruding working chamber (7).

The cylinder rod (2) has a fixed-side communication hole (16) opened to the pressurizing chamber (4), and a ring-shaped groove formed in the inner peripheral surface of the fixed valve (15). Is connected to the fixed-side communication portion (17). A hollow pipe extends from the closed end (8) of the cylinder (1) to the high-speed projecting working chamber (7) of the cylinder rod (2).
(9) is inserted, and a movable valve (12) is slidably fitted around the outer periphery of the hollow pipe (9).

The inner circumference of the movable valve (12) is in airtight sliding contact with the hollow pipe (9), and the outer circumference of the movable valve (12) is fixed to the fixed valve (15).
Is in sliding contact with the inner periphery of the airtight. A spring (14) is provided in a spring chamber (15a) between the fixed valve (15) and the movable valve (12), and always presses the movable valve (12) against the engaging portion (11). Biased in the direction. A stopper (10) protrudes from the outer periphery of the distal end of the hollow pipe (9).

The movable valve (12) is formed with a movable communication hole (18a) for connecting the high-speed protruding working chamber (7) and the spring chamber (15a) of the fixed valve (15), and further communicates therewith. The movable valve (12) is open to the outer peripheral surface through a ring-shaped movable communication portion (18). When the movable valve (12) is pressed against the stopper (10) and is engaged with the engagement portion (11), the movable communication portion (18) is fixed to the fixed communication portion (17). And are not in communication with each other.
Therefore, in this state, the high-speed projecting working chamber (7) and the pressurizing chamber (4) do not communicate with each other and are in an independent state. Here, the amount of deviation between the fixed communication part (17) and the movable communication part (18) is (Z).

In any part of the hydraulic cylinder device (A) (in this embodiment, the protruding side of the cylinder rod (2)), the cylinder rod (2) changes from "low-power high-speed protrusion" to "low-power high-power protrusion". A limit switch (19) for switching the extrusion conditions is provided.

Next, a hydraulic circuit for operating the hydraulic cylinder (A) will be described. The hydraulic pump (20) is a double solenoid type four-way switching valve (21) [Of course, it is not necessary to be a double solenoid type, but it is sufficient if four-way switching is possible. ], And switches the supply direction of the pressure oil pushed out from the hydraulic pump (20).

A one-way solenoid type four-way switching valve (24) is provided at the oil passage (a) on the side of the pressurizing chamber (4) of the cylinder (1). Is possible if possible. Is connected, and the single solenoid type four-way switching valve (24) is connected to the double solenoid type four-way switching valve (21). The other port of the single solenoid type four-way switching valve (24) is connected to the open end (C) of the hollow pipe (9), and the other exhaust port is connected to the tank (13). .

On the other hand, the profile valve (25) is connected to a branch pipe communicating with the oil pipe (a) and the connection pipe of the single solenoid type four-way switching valve (24). Port is connected to the tank (13). The profile valve (25) includes the double solenoid type four-way switching valve (21).
Pilot piping (2
5a) is connected.

Further, the oil inlet (d) of the small hole (29) for the shock absorber formed in the closed end (8) of the cylinder (1)
A control device (32) in which a flow control valve (32b) and a check valve (32a) are arranged in parallel is provided.
The pipe is connected between the direction switching valve (24) and the oil passage (a) of the pressurizing chamber (4).

A counterbalance valve (23) and a pilot check valve (22) are connected in series to the oil port (b) on the return chamber (5) side of the cylinder (1) from the side closer to the oil port (b). It is arranged.
A pilot pipe (22a) led from a port on the pushing side of the cylinder rod (2) of the two solenoid type four-way switching valve (21) is connected to the pilot check valve (22).

Next, the operation of the hydraulic cylinder (A) of the present invention will be briefly described.
(1) Submerged state before operation (Fig. 2) → Low output high speed protrusion of cylinder rod (2) → High output low speed protrusion of cylinder rod (2) → Work of work → Cylinder rod
This means that the high-output low-speed protrusion in (2) stops → the cylinder rod (2) returns at high speed.

First, the high-speed extrusion of the cylinder rod (2) will be described. As shown in FIG. 2, when the cylinder (1) is immersed, one solenoid of the four-way switching valve (21) operates to open the push-out port of the cylinder rod (2). Open the high-speed extrusion side port by the action of the spring force of the switching valve (24), and press the hydraulic pump (20).
Is supplied to the hollow pipe (9). At this time, no pressure oil is supplied from the pilot pipe (25a), and no pilot pressure is applied, so the profile valve (25) is closed.

The pressure oil supplied to the hollow pipe (9) enters the high-speed projecting working chamber (7) and moves the cylinder rod (2) to the cylinder (1).
Quickly extrude from the open end (3). Since the volume of the high-speed protruding working chamber (7) is very small, the cylinder rod (2) is rapidly pushed out from the open end (3) with a small supply amount of pressure oil.

At this time, as a reaction, the volume of the pressurizing chamber (4) suddenly increases, but the pressure oil flows from the tank (13) through the four-way switching valve (24) or the profile valve (25). A large amount of pressurized oil will be sucked in. Oil pressure ports (c) and (d) are used as pressure oil suction ports. Especially at the oil port (d)
A large amount of pressure oil flows through the check valve (32a). On the other hand, on the flow regulating valve (32b) side, since the flow rate is restricted, the inflow amount of the pressure oil becomes small.

On the other hand, on the return chamber (5) side, the cylinder rod
With the rapid protrusion of (2), the volume of the return chamber (5) decreases rapidly, and the pressurized oil is discharged accordingly. That is, the pressurized oil in the return chamber (5) passes through the counterbalance valve (23) connected to the oil inlet (b) of the return chamber (5), and the pilot check valve (22) and the four-way switching valve It flows into the tank (13) through (21).

At this time, when the pressure oil passes through the counterbalance valve (23), a certain load (internal pressure) is applied to the counterbalance valve (23), so that excessive rapid protrusion of the cylinder rod (2) is suppressed. I have. Because usually the cylinder rod
At the protruding end of (2), a tool such as a heavy punch or a die is mounted.When the cylinder (1) is arranged vertically and the cylinder rod (2) protrudes downward, the cylinder This is to prevent the projecting (falling) speed of the rod (2) from becoming excessive. By changing the load (internal pressure), the projecting speed of the cylinder rod (2) can be adjusted.

The pilot check valve (22) is opened by the pressure from the pilot pipe (22a), and the pressure oil that has passed through the counterbalance valve (23) can pass through the pilot check valve (22). It has become. Thus, the cylinder rod (2) is rapidly protruded at a certain speed.

In this high-speed ejection operation, the fixed valve (1
5) and the movable valve (12) are moving together with the cylinder rod (2), and the fixed communication part (17) and the movable communication part (18) remain disconnected. Therefore, the pressurizing chamber (4) and the high-speed projecting operating chamber (7) are kept insulated.

When the cylinder rod (2) [or the tool attached to the tip of the cylinder rod (2)] reaches just before a work (not shown), a switch (not shown) provided alongside the cylinder rod (2) is activated. The part is a limit switch (19)
To switch the operation of the cylinder rod (2) from the low-output high-speed ejection operation to the high-output low-speed ejection operation. That is, the pressure oil supply direction of the single solenoid type four-way switching valve (24) is switched by a signal from the limit switch (19).

That is, the solenoid of the four-way switching valve (24) is operated to close the supply of the pressure oil to the hollow pipe (9), and
Switch to supplying pressure oil to (4). As a result, the pressure oil is supplied into the pressurizing chamber (4) having a large sectional area, so that the cylinder rod (2) protrudes slowly from the cylinder (1) and operates at a high output. At this time, the pressurized oil pressurizing chamber
The inflow to (4) is performed through the oil inlets (a) and (d). Switching of the pressure oil supply direction by the single solenoid type four-way switching valve (24) is performed by a tool (not shown) such as a punch attached to the protruding end of the cylinder rod (2) as described above. This is the position immediately before contact with

After the switching, the cylinder rod (2)
Is extruded at a low speed and with a high output, and the work is punched, for example. During this time, the return chamber (5)
On the side, the same state as described above continues, and pressure oil continues to flow out of the return chamber (5) into the tank (13). (See Fig. 3) When the tool attached to the protruding end of the cylinder rod (2) has finished machining the work and the tool has slightly penetrated the work, the movable valve (12) stops the hollow pipe (9). Contact (10). At this point, only the stroke (X) piston part (6)
Has moved. In this state, the supply of the pressure oil to the pressurizing chamber (4) is further continued, and the cylinder rod (2) is protruded more slowly. (Refer to Fig. 4.) Then, the movable valve (12) engaged with the stopper (10) was moved by a spring according to the slow protruding operation of the cylinder rod (2).
It is pushed up against (14) and separated from the engaging portion (11). Then, as shown in FIG. 5, the movable communication part (18) of the movable valve (12) approaches the fixed communication part (17) of the fixed valve (15), and the movable communication part (18) is fixed. As soon as it communicates with the side communication part (17), the pressure oil in the pressurizing chamber (4) receives the fixed side communication hole (16), the fixed side communication part (17), the movable side communication part (18), and the movable side communication hole. (18a)
Through the high-speed protruding working chamber (7) and into the high-speed protruding working chamber (7)
From the hollow pipe (9) and the exhaust port of the four-way switching valve (24) to the tank (13). As a result, the pressure in the pressurizing chamber (4) drops sharply,
The protruding operation of (2) stops. The center distance between the movable communication part (18) and the fixed communication part (17) (the amount of deviation between them) is indicated by (Z).

In FIG. 1, the distance from the start to the stop of the protrusion of the cylinder rod (2) is defined as a safe stroke (X + Z).
Assuming that the total stroke of this cylinder device (A) is (Y), the safe stroke (X + Z) is smaller than the total stroke (Y), and at the end of the safe stroke (X + Z), the movable valve (12) Therefore, there is no accident that the cylinder rod (2) runs away and breaks the seal at the open end (3) of the cylinder (1).

When the cylinder rod (2) stops, the operation is switched to a return operation. Switching to the return operation is performed by a limit switch (not shown) or the like. In this case, the two solenoid type four-way switching valve (21) is operated, and the pressurizing chamber is operated.
The supply of pressure oil to (4) is switched to the supply of pressure oil to the return chamber (5). That is, pressure oil is supplied into the return chamber (5) through the return port of the two solenoid type four-way switching valve (21), the pilot check valve (22), and the counter balance valve (23).
Thereby, the cylinder rod (2) moves in the immersion direction.
Since the volume of the return chamber (5) is small, the cylinder rod (2) moves at a high speed in the immersion direction.

Simultaneously with this return movement, part of the pressure oil in the pressurizing chamber (4) is released from the oil inlet (a) through the profile valve (25) to the tank (13). At this time, the profile valve (2
5) is opened by the pilot pressure from the pilot pipe (25a) connected to the return port of the two solenoid type four-way switching valve (21).

The remaining portion of the pressure oil in the pressurizing chamber (4) is released from the oil inlet (d) through the flow regulating valve (32b) through the profile valve (25) to the tank (13). At this time, the flow control valve (32b) is throttled, so the flow is small, but most of the pressure oil is
It will be released from (b).

Similarly, the volume of the high-speed projecting working chamber (7) is reduced in accordance with the direction of retraction of the cylinder rod (2), and the pressure oil inside is switched between a hollow pipe (9) and a single solenoid type in four directions. Tank through exhaust port of valve (24)
Released on (13). This allows the cylinder rod
(2) sinks into the cylinder (1) and returns to the state of FIG.

At the end of the return, the closing protrusion (28) provided on the surface facing the piston (6) fits into the ring (27) provided on the inner surface of the closing end (8), and the pressure is reduced. An oil blockage space (31) is formed. At this time, since a tapered surface serving as a communication area adjusting portion (30) is formed on the outer peripheral edge of the closing protrusion (28), the pressure increases as the closing protrusion (28) fits into the ring portion (27). The communication area between the inside and outside of the oil blockage space (31) will gradually decrease.

In accordance with the decrease in the communication area, the pressure in the pressure oil closed space (31) gradually increases, the resistance increases, and the immersion speed of the piston rod (2) gradually decreases. As a result, the shock at the start of the fitting operation is killed, and the operation of returning the cylinder rod (2) is stopped very smoothly.

Further, when the closing protrusion (28) is fitted into the ring portion (27) and the pressure oil closing space (31) is completely closed, the pressure in the pressure oil closing space (31) increases rapidly. Attempt to open the oil port
Since the pressure oil blockage space (31) is connected to the flow control valve (32b) via (d), the pressure oil in the pressure oil blockage space (31) decreases with the decrease in the pressure oil blockage space (31). Is gradually released to the outside by the flow control valve (32b).
The return speed of (2) decreases. This allows the cylinder rod
The stop shock at the return of (2) is reduced.

In the above-mentioned hydraulic cylinder device (A), when the cylinder rod (2) stops, the hydraulic oil suddenly escapes, causing a shock. However, as shown in FIG. If a triangular pyramid-shaped communication area gradually increasing groove (26) communicating with (18) is formed, the communication area with the fixed side communication part (17) gradually increases with the movement of the movable valve (15), and the pressure oil escapes. The amount will increase and will stop without shock. The groove (26), which is a gradually increasing portion of the communication area, is not limited to a triangular pyramid, but may be a semiconical shape. In short, the communication area increases with the movement of the movable valve (15). Any shape may be used as long as the shape increases.

Although not shown, for example, a hollow pipe
A male screw is screwed around the lower end of (9) and a female screw is screwed around the inner circumference of the stopper (10).
The stop position of the cylinder rod (2) can be freely set by making it possible to freely advance and retract the screw (9) and fix the screw at an arbitrary position.

[0054]

According to the present invention, when the cylinder rod protrudes by a certain stroke, the movable valve incorporated in the cylinder rod in the high-speed protruding state engages with the stopper formed at the end of the hollow pipe. The movable valve moves in the direction, and the communication hole on the pressurizing chamber side and the communication hole on the high-speed protruding working chamber side communicate with each other so that the pressure oil in the pressurizing chamber can escape to the high-speed protruding working chamber side. When the rod protrudes by a certain stroke, it necessarily stops. Therefore, no malfunction occurs, the cylinder rod can be reliably stopped within the total stroke range of the hydraulic cylinder device, and the hydraulic cylinder device is not damaged.

Further, since the movable rod and the cylinder rod stopping mechanism are built in the hydraulic cylinder device, the whole device can be formed small and with good appearance.

Further, when the pressurizing chamber and the high-speed projecting operating chamber communicate with each other, the communicating area of the communicating hole for communicating the two gradually increases when they overlap each other, so that the cylinder rod is gradually stopped. It is possible to eliminate the shock at the time of stopping.

Further, the closed end of the cylinder, a ring portion forming a pressurized oil closed space when the pressurizing chamber is reduced on the opposed surface of the piston portion opposed to the closed end, and a closed protrusion fitted into the ring portion, respectively. The final stage of cylinder rod return by installing a flow control valve that communicates with the pressurized oil blockage space and gradually releases pressure oil in the pressurized oil blockage space to the outside when the pressurized oil blockage space shrinks The stop shock at the time of stopping can be reduced.

Further, as the closing protrusion fits into the ring at least one of the inner circumferential edge of the ring portion and the outer circumferential edge of the closing protrusion fitted into the ring portion, the area of communication between the inside and outside of the pressure oil blocking space is increased. By forming the communication area adjusting portion that reduces the shock, the shock at the start of the fitting operation is killed, and the operation at the return of the cylinder rod can be stopped very smoothly.

[Brief description of the drawings]

FIG. 1 is a piping diagram of a hydraulic cylinder device according to the present invention.

FIG. 2 is a front sectional view of the cylinder rod shown in FIG.

FIG. 3 is a front sectional view of the cylinder rod in FIG.

FIG. 4 is a front sectional view when the moving valve is engaged with a stopper in FIG. 1;

FIG. 5 is a front cross-sectional view when the moving valve moves and the pressurizing chamber and the high-speed projecting operating chamber communicate with each other in FIG. 1;

FIG. 6 is a perspective view of another embodiment of the communication hole in FIG. 5;

FIG. 7 is a piping diagram of a conventional example.

[Explanation of symbols]

 (1) Cylinder (2) Cylinder rod (3) Open end (4) Pressurizing chamber (5) Return chamber (6) Piston (7) High-speed protruding working chamber (8) Closed end (9) Hollow pipe (10) Stopper (11) Engagement part (12) Movable valve (13) Tank (14) Spring (15) Fixed valve

Claims (5)

[Claims] 1. A cylinder in which a cylinder rod protrudes and retracts from an open end, and a piston portion is provided so as to freely protrude and retract into the cylinder, and divides the inside of the cylinder into a pressurizing chamber and a return chamber. A hollow cylinder rod having a high-speed protruding working chamber formed therein, and a hollow pipe for pressure oil supply / discharge having a stopper inserted into the high-speed protruding working chamber of the cylinder rod from a closed end of the cylinder and having a stopper formed at the end thereof. And disposed in the hollow cylinder rod, movably attached along the hollow pipe, and constantly pressed and urged in the stopper direction, and before the stopper abuts, the engagement portion in the hollow cylinder rod is provided. After engaging with the stopper, the movable member moves in a direction away from the engaging portion to communicate the pressurizing chamber and the high-speed projecting operating chamber, and discharges the pressurized oil of the pressurizing chamber through the hollow pipe. Composed with valve A hydraulic cylinder device characterized by being constructed. 2. The hydraulic cylinder device according to claim 1, wherein, when the pressurizing chamber communicates with the high-speed protruding operating chamber, the communication section on the pressurizing chamber side that communicates the pressurizing chamber with the high-speed protruding operating chamber and the high-speed protruding operation. A hydraulic cylinder device wherein at least one of the communication portions on the chamber side is formed so as to gradually increase the communication area. 3. The hydraulic cylinder device according to claim 1, wherein a fixing position of the stopper with respect to the hollow pipe is variable. 4. The hydraulic cylinder device according to claim 1, wherein the pressure chamber is reduced on a closed end of a cylinder constituting the pressure chamber and on an opposing surface of a piston portion facing the closed end. A ring portion that sometimes forms a pressurized oil blockage and a blockage projection that fits into the ring are formed, and when the pressurized oil blockage space shrinks, the flow rate that allows the pressure oil in the pressure oil blockage space to gradually escape to the outside A hydraulic cylinder device wherein a regulating valve is installed in communication with a pressure oil closed space. 5. The hydraulic cylinder device according to claim 4, wherein the hydraulic oil is blocked as the closing protrusion fits into at least one of the inner peripheral edge of the ring portion and the outer peripheral edge of the closing protrusion fitted into the ring portion. A hydraulic cylinder device, wherein a communication area adjusting portion for reducing a communication area between inside and outside of a space is formed.