JPS6223412B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pneumatic operating device for a breaker.

In general, there are various means for causing the closing or disconnecting operation of the shield disconnector. One of these means uses compressed air pressure and spring force. FIG. 1 is a schematic configuration diagram showing an operating device for a vacuum shield disconnector, and FIG. 2 is a sectional view showing a conventional example of the operating device used in FIG. 1. In FIG. 1, 1 is a vacuum interrupter, 2 is a pressure contact mechanism, 3 is an operating device, 4 is a closing/shutdown air switching valve, and 5 is a compressed air tank. FIG. 2 shows a specific example of the operating device 3, in which 6 is a first cylinder;
A first piston 7 is fitted into the cylinder 6 in a slidable but airtight manner. 8 is the first
This is a first piston shaft screwed onto the piston 7 with a nut 9. 10. This spring 1
0 is inserted between one end of the first cylinder 6 and the piston 7. 11 is a ventilation hole. A stepped portion 7a is formed on the first piston 7, and this stepped portion 7a is formed to abut against a stepped portion 12a of the second cylinder 12. Said second cylinder 12
is connected and fixed to the first cylinder 6 by a bolt 13. 14 is an input air supply hole bored in the second cylinder 12, and 15 is an opening having a relatively large diameter. An exhaust valve 16 is disposed in this opening 15 . 17 is the third cylinder, and this third cylinder 1
A second piston 18 is slidably fitted into the second piston 7 . A second piston shaft 19 is screwed onto the second piston 18 with a nut 20, and the exhaust valve 16 is fixed with a nut 21. 22 is a second piston return spring, and 23 is an exhaust hole. This exhaust hole 23 communicates with the opening 15. 24 is an air supply hole. Note that the third cylinder 17 is fixed to the second cylinder 12 with a bolt 25.

In the air operating device configured as described above, when a command to close the breaker is issued, the switching valve 4
operates, and air is supplied into the second cylinder 12 from the input air supply hole 14. With this air supply, the first
The piston 7 is moved upward while accumulating the force of the armature and the cutting spring 10, and the vacuum interrupter 1 is turned on. Next, when a command to shut off the shear is issued, the switching valve 4 is switched, and air is supplied from the shear air supply hole 24 to the third cylinder 17 . The second piston 18 is slid to the left by this air supply, and the exhaust valve 1
In order to open the first piston 7 and the spring 10
It is moved downward by the release of force. When the lower end of the first piston 7 begins to fit into the stepped portion 12a of the second cylinder 12, the pressure in the air chamber 26 increases, the downward movement speed of the first piston 7 is reduced, and the first piston 7
The lower surface of the step 7a is the step 12 of the second cylinder 12.
The violent collision with the upper surface of a is alleviated. However, in the piston shock absorbing device using the air chamber 26 formed by fitting the first piston 7 and the second cylinder 12, the shock absorbing effect is low because the air chamber 26 does not have sufficient pressure at first. As the piston 7 gradually moves downward, the pressure in the air chamber 26 increases, creating a buffering effect. In such a shock absorbing device, in order to improve the shock absorbing effect, the first piston 7 and the second cylinder 12 should be fitted with each other.
It is possible to make the stroke of the piston 7 longer, but this has the disadvantage that the operating device becomes larger. Furthermore, even if the stroke is long as described above, the buffering effect will occur near the final position of the stroke, just like when the stroke is short, so there is no point in making the stroke longer. When the end is
There is also a risk that the cylinder 12 will be caught by the stepped portion 12a, making it impossible to shred it.

This invention eliminates the above-mentioned drawbacks, and when the sheath breaks, the collision shaft collides with the buffer piston and the small-diameter piston is directly buffered. A desired deceleration can be obtained, and the large-diameter piston and the small-diameter piston can slide smoothly without center runout. The purpose of the present invention is to provide a pneumatic operating device for a breaker.

An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 3 to 6, the same parts as in FIGS. 1 and 2 are designated by the same reference numerals. 27
is a double operation piston that slides in the first and second cylinders 6 and 12, and this double operation piston 27 is composed of a large diameter piston 28 and a small diameter piston 29. The large diameter piston 28 is axially connected to the piston shaft 2.
8a, 28b, piston shafts 28a, 28b
A recess 30 is bored inside. The small diameter piston 29 is housed in the recess 30 and
Slide inside. A piston shaft 8 is integrally formed with the small diameter piston 29, and this piston shaft 8
In the opposite direction, a collision shaft 29a is integrally constructed in the same manner as described above. The collision shaft 29a protrudes somewhat from the lower end of the piston shaft 28a during interruption, and is supported by a bearing 31 formed on the inner circumferential wall of the end of the piston shaft 28a. A check valve 32 and a ventilation hole 31a are formed in the bearing 31. 34
is a return spring for the small diameter piston 29 disposed within the recess 30. A stopper piece 35 of the large diameter piston 28 is provided in the second cylinder 12 to protrude in the radial direction. 36 is a buffer device, and this buffer device 36
is a chamber 37 disposed on the axis of the dual operation piston 27 and bored outside the second cylinder 12;
A cap-shaped shock-absorbing piston 38 is slidably fitted to the cap-shaped shock absorbing piston 38. The protrusion 38a of the piston 38 penetrates the wall of the second cylinder 12 and protrudes into the cylinder, and the collision shaft 29a is brought into contact with the upper surface of the protrusion 38a. The chamber 37 is kept airtight by a check valve 39 and a closing member 41 provided with an air supply hole 40 communicating with the input air supply hole 14 . 42 is a ventilation hole, and 43 is a return spring.

Next, the operation of the above embodiment will be described. FIG. 3 In the state at the time of starting the closing of the cutter, if a closing command is given now, the air supply hole 40 and the input air supply hole 14
Air is introduced into the second cylinder 12 through the
The large diameter piston 28 begins to move upward. Due to the upward movement of the large-diameter piston 28, the shear spring 10 is loaded with energy. On the other hand, the air also flows into the recesses 30 in the piston shafts 28a and 28b via the check valve 32,
The small-diameter piston 29 is also moved upward, and the disconnector is turned on. Furthermore, the air that has flowed into the air supply hole 40 flows into the chamber 37 within the shock absorber 36 via the check valve 39 . The piston 38 is moved upward by this incoming air.

FIG. 4 shows the state of movement of the dual operation piston 27 and the buffer piston 38 of the buffer device 36 when the injection is completed. In FIG. 4, the inside of the second cylinder 12 is filled with air. To sinter the mustard cutter in this feeding state, the mustard cutter supply hole 2
Supply air to 4. By this air supply, the piston 18 is moved to the left in the figure, and the exhaust valve 16 is opened. This state is shown in FIG. By opening the exhaust valve 16, the air in the second cylinder 12 is exhausted, and the large diameter piston 28 is rapidly moved downward under the action of the serpentine spring 10. As the large-diameter piston 38 descends, the small-diameter piston 29 also descends, and the end of the collision shaft 29a collides with the protrusion 3 of the piston 38.
Collided by 8a. Therefore, the movable lead rod of the vacuum shield breaker 1 is directly buffered by the shock absorber 36 via the insulating rod, the piston shaft 8, and the small diameter piston 29, so that the vacuum shield breaker 1 can be easily buffered. The speed during disconnection can be ideally reduced. This eliminates the burden on the bellows, etc. of the vacuum chamber and disconnector, and improves the durability of the vacuum chamber and disconnector. FIG. 6 shows the state when the shingle cutting is completed.

As described above, according to the present invention, a chamber is provided at the bottom of the cylinder facing the double operation piston, and the double operation piston is fitted into the chamber while being biased upwardly by a retaining spring.
A buffer piston is provided located on the axis of the heavy operation piston, and a check valve is provided in a passage communicating between the air supply hole that supplies air for driving the operation piston to the cylinder and the chamber, and a check valve is provided in a passage that communicates between the inside of the cylinder and the chamber. A ventilation hole is provided in each of the buffer piston and the wall forming the chamber so as to communicate with each other, and a collision shaft that contacts the buffer piston extends in a direction opposite to the piston axis of the small diameter piston. The collision shaft is supported by a bearing provided at the end of the large-diameter piston, and the bearing is provided with an air passage that communicates the inside of the large-diameter piston with the inside of the cylinder, so that the collision shaft will not collide with the shock absorber in the event of a shear failure. Since the small-diameter piston is directly buffered by the small-diameter piston, the movable lead rod of the vacuum shield breaker connected to the small-diameter piston can obtain the desired deceleration, and the center runout between the large-diameter piston and the small-diameter piston can be prevented. This has the effect of allowing smooth sliding without any friction.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing a conventional pneumatic operating device for a breaker, Fig. 2 is a sectional view showing details of the operating device in Fig. 1, and Figs. 3 to 6 are one embodiment of the present invention. It is a sectional view showing an example. 6...First cylinder, 8...Piston shaft, 10
...Shiyadan spring, 12...Second cylinder, 27...
...Double piston, 28...Large diameter piston, 29...
...Small diameter piston, 29a...Collision shaft, 30...Recess, 31...Bearing, 32, 39...Check valve, 36
...Buffer device, 38...Piston.

Claims (1)

[Scope of Claims] 1. An operating piston that is slidably operated by supplying compressed air is inserted into a cylinder, and this operating piston is inserted into a large diameter piston and a small diameter piston that is slidably inserted into the large diameter piston. In an air operating device, the piston shaft of the small diameter piston passes through the upper part of the large diameter piston and is led out of the cylinder, and is interlocked and connected to the movable shaft of the shingle breaker. A chamber is provided at the bottom of the cylinder facing the operating piston, and a retaining spring is used to force the cylinder upwardly and the buffer piston is fitted into the chamber. A check valve is provided in a passage communicating between an air supply hole that supplies air to the cylinder and the chamber, and a vent hole is provided in each of the walls forming the buffer piston and the chamber so as to communicate between the inside of the cylinder and the chamber. A collision shaft that contacts the buffer piston extends in the opposite direction to the piston axis of the small diameter piston, and the collision shaft is supported by a bearing provided at the end of the large diameter piston. An air operating device for air disconnectors that has an air passage in the bearing that communicates between the inside of the cylinder and the inside of the cylinder.