JPS6228033Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operating device for a sheath cutter, and more particularly to a shear cutter operating device that uses compressed air and a spring to perform closing and cutting operations.

The first example is a conventional vacuum cutter and a vacuum cutter.
As shown in the figure. In the figure, 1 is an operating section, 2 is a cylinder provided in the operating section 1, 2a and 2b are an input air hole and a cooling air hole provided in the cylinder 2, respectively, and 3 is a cylinder housed in the cylinder 2. 4 is a piston rod that is integrally attached to the piston 3 and is slidably inserted into the cylinder 2; 5 is a support insulator tube that is attached to the upper part of the operating section 1; 6 is a bearing frame 7 that is attached to the upper part of the support insulator tube 5. 9 and 10 are respectively fixing of the shingle section 8. Leads and movable leads 9a and 10a are fixed electrodes and movable electrodes 11 fixed to fixed leads 9 and movable leads 10, respectively, and are bottomed cylindrical connecting members connected to piston rods 4 via insulated rods 12. The member 11 is slidably supported by the bearing frame 7. Reference numeral 13 denotes a pressure contact spring housed within the connection member 11. The lower end of the movable lead 10 is slidably inserted into the connection member 11, and the connection member 11 and the pressure contact spring 13 constitute a pressure contact mechanism. 14 is a bearing for the piston rod 4.

In the above conventional device, when charging, the charging air hole 2
Air is introduced from a to move the piston 3 upward, thereby bringing the movable electrode 10a into contact with the fixed electrode 9a, and further moving the piston 3 upward to compress the pressure contact spring 13, thereby bringing the movable electrode 10a into contact with the fixed electrode 9a. press against. Also, when the sheathing is to be interrupted, air is introduced from the shearing-cutting air hole 2b to move the piston 3 downward, thereby performing the shearing operation.

By the way, in order to simplify the structure of the above-mentioned conventional device, the present applicant eliminated the pressure contact spring 13, etc., and integrally connected the insulating rod 12 with the movable lead 10, and in the closed state, air pressure is applied from the closing air hole 2a. The idea was to press the movable electrode 10a against the fixed electrode 9a by constantly charging the air. However, in this case, if the area of the upper surface of the piston 3 is made to the required size to obtain the speed required for shearing, the area of the lower surface multiplied by the air pressure becomes the closing force and pressing force, so the pressure welding A problem arises in that the force becomes excessive and an excessive load is placed on the constituent members such as the leads 9 and 10.

This invention has been developed in view of the above points, and it is possible to prevent welding of each lead part due to the loss of pressure contact at the moment of breakage, as well as to prevent overtravel of the movable lead. The purpose is to provide an operating device.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. As shown in FIGS. 2A and 2B, the operating section 1 communicates with a cylinder 2 having a piston rod 4 connected to an insulating rod 12 through an input air hole 2a and an air source. switching valve 1 switchably connected to 19;
It has 8.

More specifically, in FIGS. 3A and 3B, 15 is a small diameter piston housed within the cylinder 2 and integrally connected to the movable reed 10 via the piston rod 4 and the insulating rod 12. 16 is cylinder 2 and small diameter piston 15
A large-diameter piston 17 is provided between the upper surface of the large-diameter piston 16 and the upper inner wall surface of the cylinder 2. It is definitely a breaking spring. Further, a sphere 22 is housed inside the large-diameter piston 16 to close a small-diameter ventilation hole 16c formed at the center of the bottom thereof, and a check valve 23 is formed by the sphere 22 and the ventilation hole 16c. ing. A relatively small auxiliary spring 24 is elastically mounted between the bottom of the large diameter piston 16 and the end of the small diameter piston 15.

According to the operating device having the above configuration, when the switching valve 18 is energized in the shrunken state shown in FIG. 2A, the spool 20 moves to the right against the return spring 21, and as shown in FIG.
As shown in FIG. 2, the input air hole 2a and the air source 19 communicate with each other, and the air is introduced into the air cylinder 2. Therefore, the large diameter piston 16 is pushed up, and the small diameter piston 15 is also pushed up by the air passing through the vent hole 16c formed in the flange 16b, and both pistons 15 and 16 rise together. As a result, as shown in FIG.
The shear distance L ₁ between a and 10a and the large diameter piston 1
Since there is a relationship of L ₂ > L ₁ with the moving distance _L 2 of 6, a gap A is created between both pistons 15 and 16 in the closed state, and the air pressure in the room formed by this gap A also acts as the electrode pressure contact amount. do. Also at this time,
The auxiliary spring 24 generates pressure contact force in an auxiliary manner, but since the spring force of this spring 24 is extremely small compared to the compressed air pressure, it is only useful for fine adjustment of the pressure contact force.

In the closed state, the switching valve 18 is constantly energized to fill the cylinder 2 with air to maintain the pressure contact between the electrodes 9a and 10a. Next, when the heat is cut off, the switching valve 1
When the excitation of 8 is released, the spool 20 returns to the spring 2.
1 and moves to the left, the pipe connecting the air cylinder 2 and the air source 19 is suddenly cut off,
Air cylinder 2 is communicated. As a result, the air pressure within the air cylinder 2 decreases, and the shear section 8 is rapidly shattered by the spring force of the shear spring 17. The small diameter piston 1
The outflow of the air inside 5 is prevented by the action of the check valve 23. Therefore, when the air cylinder 2
Even if the air pressure inside drops instantaneously, pressure is applied between the movable and fixed electrodes. This makes it possible to time the opening of both contacts and to prevent overtravel of the movable electrode 10a.

Here, the meaning of providing the check valve 23 in the small diameter piston 15 is that when the cooling is interrupted, the supply of air from the input air hole 2a is stopped.
If 3 is not provided, the pressure contact force will be zero, and since the gap A exists, the cutting operation will not start. Therefore, both electrodes 9a and 10a may be heated and welded together. However, due to the presence of the check valve 23, the pressure contact force is maintained until the engaging portion 16a of the large-diameter piston 16 engages with the small-diameter piston 15, and the welding operation starts at the moment of this engagement. The disconnection operation eliminates the possibility of welding of both leads.

Furthermore, the reason why the auxiliary spring 24 is housed inside the large diameter piston 16 is that when the operating pressure is in the off position, the positional relationship between the large diameter piston 16 and the small diameter piston becomes unstable, and the operating performance deteriorates. This is to prevent this from happening, as there is a risk that it may drop. In other words, even if air leaks from the check valve 23 in the large-diameter piston 16 and the pressure in the large-diameter piston 16 disappears when the breaker is in the shattered state, the spring force of the spring 24 causes the large-diameter piston to close. A predetermined positional relationship between the piston 16 and the small diameter piston 15 is maintained,
Improves performance during loading operations.

As explained above, in the present invention, the operating piston is a combination of a small diameter piston for contact pressure welding and a large diameter piston for storing tension spring, the small diameter piston is included in the large diameter piston, and the large diameter piston is reversed. A stop valve is provided, and this check valve allows air to flow into the large diameter piston and prevent it from flowing out to the outside. Even if there is no operating pressure inside the large-diameter piston, it always operates as specified.

Therefore, even from the moment of shearing to when the large-diameter piston engages with the small-diameter piston and the shearing operation is actually performed, a small pressure contact force remains, so the shearing stroke becomes longer. Since the shearing kinetic energy is obtained, the pressure-receiving area of the large-diameter piston can be small, allowing the cylinder diameter to be made smaller, as well as eliminating the need for pressure springs and making it possible to downsize the shearing spring, making the device more compact. be done. In addition, overtravel during shearing is suppressed by the air pressure inside the large-diameter piston, and an auxiliary spring housed within the large-diameter piston maintains the predetermined positions of the large-diameter piston and small-diameter piston when shearing is complete. Since the relationship can be maintained, a high-performance operating device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view of a conventional vacuum breaker, FIGS. 2A and 2B are longitudinal sectional front views of the vacuum breaker according to the present invention in the breaker state and closed state, respectively, and FIG. 3A , B are enlarged longitudinal sectional front views of essential parts of the vacuum shear breaker according to the present invention in the sheared state and closed state, respectively. 2...Cylinder, 2a...Air injection hole, 2b
...Shrinking air hole, 4...Piston rod, 8
...Shining section, 9a...Fixed electrode, 10a...Movable electrode, 12...Insulating rod, 15...Small diameter piston, 16...Large diameter piston, 16a...Engaging portion, 16b...Slip edge Part, 16c...Vent hole, 17
...Shipping spring, 18...Switching valve, 19...Pneumatic pressure source, 22...Sphere, 23...Check valve, 24...
Auxiliary spring.

Claims (1)

[Claims for Utility Model Registration] A cylinder having an input air hole and a shingle disconnection air hole; a large-diameter piston that is housed and has a cavity that communicates with the input air hole; and a large-diameter piston that is slidably housed within the cavity of the large-diameter piston and is integrally connected to the movable side of the bow section. a small-diameter piston that engages with the large-diameter piston during opening and closing operations; an auxiliary spring provided between the large-diameter piston and the small-diameter piston within the cavity of the large-diameter piston; and an auxiliary spring housed within the cylinder. A blade spring that urges the large diameter piston in the cross section direction of the blade section, a small hole provided in the large diameter piston, and a sphere that engages with the small hole. A check valve provided to allow only air to flow into the cylinder is connected to the cylinder and an air source so that charging and exhausting can be switched, and when the cylinder is turned on, air is supplied to the cylinder and the cylinder is kept in the turned-on state. 1. An operating device for a shear cutter, comprising a switching valve that constantly supplies air into a cylinder to press the movable side of the sheath cutter to the fixed side of the sheath cutter.