JPH0749050Y2 - Locking device for fluid pressure cylinder - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock device for holding a rod of a fluid pressure cylinder in a stopped state.

[0002]

2. Description of the Related Art As a fluid pressure cylinder having a lock mechanism for stopping a piston at an appropriate position, various fluid pressure cylinders having various configurations have been known. Such a locking mechanism is disclosed in, for example, Japanese Patent Laid-Open No. 62-204005 and Japanese Patent Laid-Open No. 63-204005.
As disclosed in Japanese Patent Publication No. 180705, it is customary to press a brake shoe against a cylinder rod with a ball, but a lock mechanism of this type applies a well-balanced braking force to the cylinder rod. Even if it is advantageous in that it can be done, since the ball transmits the braking force by point contact, a large braking force cannot be obtained, and it is necessary to consider increasing the number of balls to increase the braking force, As a result, not only does the device grow in size,
The structure becomes complicated, the assembly becomes troublesome, and the possibility of an unexpected failure increases.

The failure of this type of locking mechanism causes a dangerous state in which the device whose drive is controlled by the cylinder starts mechanical movement due to the sudden operation of the cylinder in the stopped state. Because there is a possibility
It is necessary to simplify the structure as much as possible to eliminate the possibility of failure.

[0004]

The technical problem to be solved by the present invention is to realize an increase in the braking force in the above-mentioned lock mechanism without increasing the size of the device or complicating the structure, and
It is to obtain a rod mechanism that is simple and has few failures.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is a locking device for holding a piston rod of a fluid pressure cylinder and locking the piston rod. The brake shoe holder is held in the lock mechanism body, which has a shaft hole that allows the piston rod of the fluid pressure cylinder to penetrate airtightly, by restraining movement of the rod in the axial direction. Sliding freely,
A spring for urging the brake piston in the braking operation direction is applied to the brake piston, and a pressure fluid supply / discharge port is opened in the pressure chamber on the side that applies the urging force against the spring to hold the brake shoe. the holder which is to several dividing a cylindrical member in the circumferential direction to form an abutment surface of the roller in their outer surface in a plane, the externally fitted retainer was above holder, or the number of the surrounding a concave portion is provided at houses each said roller to their recesses, in each recess, the housing and rollers in contact with the abutment surface of the surface of the holder, the recess portion of the retainer, respectively,
The inner surface is an inclined flat surface that contacts the roller, and the outer surface is the above
Abut the inner surface of the brake cylinder of the brake piston
A tapered piece with a cylindrical surface is slidably inserted in the sliding direction of the brake piston, and the tapered piece is inserted into the above-mentioned block.
It is characterized in that the movement of the piston in the sliding direction is restrained and held inside the rake operating cylinder .

[0006]

When the pressure fluid is supplied from the supply / discharge port to the pressure chamber on one side of the brake piston, the driving force thereof drives the brake piston against the urging force of the spring,
In this state, the taper piece held by the brake cylinder of the brake piston does not come into pressure contact with the roller, so
The tightening of the piston rod by the brake shoe is released, and the lock of the rod by the lock mechanism is released.

[0007] discharging the pressure chamber of the pressure fluid from the supply and discharge ports, the brake piston is made to return to the pressure chamber side by the biasing force of the spring, the inclined plane of each Tepapisu is pressed against the respective roller with it, these rows
The brake shoe is pressed against the rod through the holder that is divided into several pieces . In this case, using the roller,
Since the surface that the roller contacts is flat,
The rollers make line contact with those faces, increasing the contact area,
It is possible to provide sufficient surface pressure strength with a small number of rollers.

This locking mechanism is provided with several recesses in the retainer.
A roller and a taper piece are arranged in each part,
Of the roller is abutted on the flat surface of the holder
And the outer surface of each taper piece
The inner surface is a cylindrical surface, and the inner surface is an inclined flat surface.
As a result, the taper pieces are
Since the pressing force can be transmitted independently, these parts
It is possible to absorb variations in processing accuracy of products. Well
Also, the opposed surfaces of the pair of cylindrical members are tapered.
You don't have to center these parts
The overall assembly is simple and, as a result, an increase in the braking force in the lock mechanism is achieved without increasing the size of the device or complicating the assembly. It is possible to obtain a rod mechanism with less power consumption.

[0009]

1 and 2 show the construction of the lock mechanism and its essential parts of the present invention. The lock mechanism 1 includes a base end cover 3 that also serves as a rod cover of a cylinder tube 2 of a fluid pressure cylinder, a tip end cover 4 facing the base end cover 3, and a brake cylinder tube 5 that connects them, and these are integrally formed. The lock mechanism body is configured by connecting to the.

The lock mechanism main body is provided with a rod shaft hole at the center thereof so that the rod 6 of the fluid pressure cylinder can penetrate through the center in a gastight manner through a seal, and further the base end cover 3
Between the end cover 4 and the front cover 4, the holder 8 of the brake shoe 7 that holds the rod 6 is held by the base cover 3 and the front cover 4 in order to hold the holder 8 while restraining the movement of the rod in the axial direction. 9 and 10 are held, and a holder 8 of the brake shoe 7 described later is arranged between the holding cylinders 9 and 10.

The holding cylinder 10 has its peripheral surface smoothed as a sliding surface on which the brake piston 11 slides.
A brake piston 11 is airtightly and slidably fitted between the cylinder tube 5 and the holding cylinder 10.
The piston 11 is integrally provided with a brake operating cylinder 12 extending to the holding cylinder 9 side, and a spring 13 is compressed around the brake operating cylinder 12 between the brake piston 11 and a spring receiver on the base end cover 3 side. The brake piston 11 is biased by the spring 13 toward the tip cover 4 side, that is, in the brake operating direction.

Further, compressed air is sent into a pressure chamber 14 provided between the brake piston 11 and the tip cover 4, and the brake piston 11 is attached to the base end cover 3 side against the biasing force of the spring 13. In order to urge, a pressure fluid supply / discharge port 15 communicating with the pressure chamber 14 is opened in the tip cover 4, while a breathing port provided in the base end cover 3 is provided between the piston 11 and the base end cover 3. It is opened to the outside by 16.

The brake shoe 7 and the holder 8 have a structure as clearly shown in FIG. That is,
The brake shoe 7 is configured such that a diameter of the brake shoe 7 can be reduced by providing a split 7a in a part of a cylindrical member adhered to the rod 6, and a holder that holds the brake shoe 7 and applies a braking force to it. Reference numeral 8 denotes a tubular body that is divided into four parts with a space required for reducing the diameter. A groove for accommodating and holding the brake shoe 7 is provided on the inner peripheral surface of the cylindrical body, and the contact surface of the roller 17 on the outer surface thereof. 8a is formed in a planar shape.

A retainer 18 for holding the roller 17
Is fitted onto the holder 8 and accommodates the rollers 17 in the recesses 18a provided at four locations around the retainer 18, and the rollers 17 accommodated therein are placed on the surface of the holder 8 in the recesses 18a. It is in contact with the contact surface 8a.

Further, taper pieces 19 are slidably inserted in the four recesses 18a around the retainer 18 in the sliding direction of the brake piston 11, respectively. The taper piece 19 has an outer peripheral surface 19a formed into a cylindrical surface that abuts the inner surface of the brake actuating cylinder 12 of the piston 11, and an inner surface 19b formed into an inclined flat surface that abuts the roller 17.
1. Inside the brake operating cylinder 12 in FIG.
It is fitted in a state in which the movement in the sliding direction is restricted. Therefore, the taper piece 19 is positioned by the retainer 18 and the brake operating cylinder 12.

In the figure, 21 is a spring for urging the retainer 18 in a direction in which the roller 17 held by the retainer 18 abuts the inner surface 19b of the taper piece 19, and 22
Indicates a port for supplying / discharging pressurized air to / from the pressure chamber in the fluid pressure cylinder.

Next, the operation of the lock device will be described. In the state shown in the upper half of FIG. 1, the supply / discharge port 15
When pressurized air is supplied from the pressure chamber 14 to the pressure chamber 14, the driving force drives the brake piston 11 against the urging force of the spring 13 to the stroke end on the base end cover 3 side as shown in the lower half of the figure. It In this state, since the taper piece 19 held by the brake actuating cylinder 12 of the brake piston 11 does not press against the roller 17, the tightening of the rod 6 by the brake shoe 7 is released and the locking of the rod 6 by the lock mechanism 1 is released. Is in a state.

In this state, the supply / discharge port 15 to the pressure chamber 14
When the pressurized air inside is discharged, the brake piston 11 is returned to the pressure chamber side by the urging force of the spring 13, as shown in the upper half of FIG. Brake shoes 7
Is pressed against the rod 6. That is, the recess 1 of the retainer 18
The roller 17 positioned at 8a is pressed against the four-divided holders 8 by pressing the slopes of the taper pieces 19 held by the brake piston 11 driven by the springs 13, and splits the rollers 17 through the holders.
The brake shoe 7 containing a is pressed to lock the piston rod 6.

In this case, since the roller 17 is used in place of the conventional ball and the contact surface of the roller is formed in a flat shape, the roller 17 makes a line contact with these surfaces and the contact area increases. And there is no need to arrange the rollers in multiple rows,
Sufficient surface pressure strength can be provided with a small number of rollers arranged in one row. Also, the holder 8 is divided into several parts,
The roller 17 and the taper piece 19 are separated from each other.
Since it comes into pressure contact with the contact surface 8a of the holder 8, the braking force is evenly distributed.
And the retainer 18 divides the holder
The roller 17 and the taper piece 19 on the contact surface 8a of the da 8
Since they are held in correspondence with each other, overall assembly
Can be done easily.

[0020]

As described above, according to the present invention, the increase of the braking force in the lock mechanism is realized without enlarging the device and complicating the structure, and the structure is simplified. It is possible to obtain a rod mechanism that is small and has few failures. Also, the holder is divided by the retainer.
Align the roller and taper piece to the contact surface of
Since it is held in place, it is easy to carry out the overall assembly.
You can Provided on the retainer by the divided holder
Since the roller and the taper piece are held in correspondence with each other, the whole assembling can be easily performed.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing a locked state (upper half) and an unlocked state (lower half) of an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of the above embodiment.

[Explanation of symbols]

1 lock mechanism, 13 springs, 5 brake cylinder tubes, 14
Pressure chamber, 6 rods, 15
Supply / discharge port, 7 brake shoes,
17 rollers, 8 holders,
18 retainer, 8a contact surface, 18a recess, 11 brake piston, 19
Taper piece, 12 brake cylinder,
19b inner surface,

Claims (1)

[Scope of utility model registration request] 1. A lock device for holding a piston rod of a fluid pressure cylinder to lock the rod, the brake device including a brake cylinder tube and a shaft hole at the center of which penetrates the piston rod of the fluid pressure cylinder in an airtight manner. The brake shoe holder inside the lock mechanism body.
The rod is restrained from moving in the axial direction and held, and a brake piston is slidably fitted in the cylinder tube, and a spring for urging the brake piston in the brake operating direction is applied to the brake piston. and Seki設supply and discharge port of the pressure fluid to the pressure chamber on the side for applying a biasing force against the spring, the holder for holding the brake shoe, the circumference of the tubular body
The retainer that is externally fitted to the holder is provided with concave portions at several places around the retainer, and the concave portions are formed in the concave portions. respectively housing the rollers, in each recess, the housing and rollers in contact with the abutment surface of the surface of the host <br/> holder, the recess portion of the retainer, respectively, the inner surface in contact with the roller tilt A flat surface, the outer surface of which is the brake piston
The taper piece, which is a cylindrical surface that comes into contact with the inner peripheral surface of the brake operating cylinder, is slidably inserted in the sliding direction of the brake piston, and this taper piece is inserted inside the brake operating cylinder in the sliding direction of the piston. A locking device for a fluid pressure cylinder, characterized in that movement is restricted and held.