JPH0252373B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a hydraulic operating device for a circuit breaker, and more particularly to a hydraulic operating device for a circuit breaker having a position holding mechanism for maintaining a closed state of a movable element.

[Background of the invention]

Generally, a circuit breaker operating device is required to have extremely high-speed operating characteristics, and is also required to reliably maintain a closed state in an operating state to guarantee current carrying performance.

For example, in a circuit breaker operating device as shown in Japanese Patent Application Laid-Open No. 56-93227, the operating piston is held in position by hydraulic pressure as shown in Fig. 6, thereby maintaining the closed state. .

FIG. 6 shows the closed state of the circuit breaker, and an operating piston 6 is connected to an operating rod 15 that is connected to a mover of a not-shown interrupting section. This operating piston 6 is arranged so as to be able to reciprocate within the operating cylinder 16, and moves inside the operating cylinder 16 into a chamber C and a chamber D.
It is divided into Chamber D is connected to a hydraulic pump 9 via a filter 8, and is also directly connected to an accumulator 5, and is constantly filled with high pressure oil. on the other hand,
The chamber C is controlled by a main control valve 2 and a pilot valve 1 which serves as its operating signal source. When the chamber C is filled with high pressure oil as shown in the figure, the operating piston 6 is caused by the difference in diameter between the operating rods 15 and 17 connected to both sides of the operating piston 6 and led out of the operating cylinder 16. The operating piston 6 is driven to the right in the figure due to the difference in pressure receiving areas on the left and right sides, and the shutoff section is closed. However, when the high-pressure oil in the chamber C is discharged, the operating piston 6 is driven to the left by the high-pressure oil in the chamber D, and the shut-off section is brought into the shut-off state. The operating piston 6, operating cylinder 16, and operating rods 15, 17 in the above description constitute the operating valve 3.

In such a general hydraulic operating device, chamber C
If an oil leak occurs inside the operating piston 6,
The force for holding the position in the closed state decreases or disappears, and the operating piston 6 cannot be maintained in the fully closed state and is driven by the external force acting on the operating rods 15 and 17.

Such forces acting on the operating piston 6 include the weight of the cut-off part, the spring that provides contact pressure between the closing contact and the cut-off part, and the driving force for the pressure-receiving area due to the pressure of the arc-extinguishing gas in the circuit breaker tank. Conceivable.
Generally, these external forces act as a whole in the blocking direction of the blocking section. In this way, if the operating piston 6 were to be driven in the cutoff direction, the contactors in the cutoff part would open and discharge would occur between the contacts, causing damage to the contacts and making it impossible to guarantee current carrying performance. It ends up.

Therefore, in general, the operating rod 15 of the hydraulic actuator
As shown in FIG. 7, a position holding mechanism 18 was constructed using a toggle spring mechanism. However, this position holding mechanism 18 is a toggle spring mechanism using a compression spring, and if the outer fixed end is supported for pendulum movement, the axial length becomes large, and the operation box 34 that houses the operating device also becomes large. was.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic operating device for a circuit breaker having a miniaturized position holding mechanism.

[Summary of the invention]

The present invention comprises a position holding mechanism that converts the force of a spring located in the radial direction with respect to the operating rod to hold the operating rod in the closing position. An engaging part is formed on the operating rod on the opposite side of the movable element, and a rolling element biased by a spring in the radial direction of the operating rod is applied to the engaging part, so that the engaging part is It is characterized in that the operating direction of the spring is changed so that the operating rod is biased in the closing direction by the tapered surface.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an enlarged view of the main parts of the hydraulic actuator corresponding to the closed state of the shut-off part. An operating rod 15 for driving the operating rod 15 is connected thereto, and an operating rod 17 having a smaller diameter than the operating rod 15 is connected to the other side. The two actuating rods 15, 17 are led out of the actuating cylinder 16 in a gas-tight manner via seals 30, 31, respectively.

A position holding mechanism is constructed on the operation rod 17 side of the operation cylinder 16, and this position holding mechanism will be explained next.

A position holding mechanism guide 27 is coupled to the end surface of the operation cylinder 16, and a compression spring 23 is installed inside the guide 27.
A movable frame 20 surrounding the tip of the compression spring 23 is slidably fitted thereto. A pair of movable frames 20 are provided, and a rolling element, such as a roller or a ball, is rotatably attached to the tip end of the movable frame 20. In this embodiment, a roller 22 is attached as a rolling element. The engaging member 19, which has a surface that is pressed against the roller 22, is screwed and fixed to a threaded portion formed on the end surface of the operating rod 17. As shown in FIG.
After housing the compression spring 23 fixed to the cover 6 and arranged radially with respect to the operating rod 17, the cover 26 is fixed with bolts 33.

FIG. 3 shows an enlarged view of the vicinity of one of the compression springs 23 mentioned above, and the inner diameter of the position holding mechanism guide 27 is smaller than the inner diameter of the cover 26, and a stopper 27a is formed at the joint between the two. has been done. The collar 20a of the movable frame 20, which is slidably fitted into the stopper 27a, comes into contact with the stopper 27a, and constitutes a protrusion regulating means that prevents the movable frame 20 from protruding beyond a predetermined position. The movable frame 20 has a cylindrical shape with a bottom on the operating rod 17 side, and a compression spring 23 is disposed between the cover 26 and the bottom, so that the collar 20a is always pressed against the stopper 27a. This movable frame 20
As shown in FIGS. 4 and 5, there is a pair of upright portions 20b at the bottom, and a roller 22 is rotatably mounted on a pin 24 bridging the upright portions 20b. End protrusions of bolts 25 shown in FIGS. 3 and 5 are in contact with the opposing surfaces of each of the upright portions 20b. Therefore, even if the movable frame 20 moves up and down, it does not rotate in the circumferential direction,
It never shifts. This means that the roller 22 always comes into contact with the engagement member 19 in a predetermined direction. Further, the protrusion regulating means described above is configured so that when the collar 20a of the movable frame 20 comes into contact with the stopper 27a, the roller 22 does not come into contact with the outer peripheral surface of the operating rod 17 except for the engaging member 19.

The engaging member 19 has a tapered surface facing upward to the right.
The roller 22 comes into contact with a part of this tapered surface.

In the closed state shown in FIG. 3, the collar 20a of the movable frame 20 is slightly lifted from the stopper 27a, so the engaging member 19 is pressed against the roller 22, pushing the roller 22 upward slightly.
Therefore, the spring force of the compression spring 23 acts on the operating rod 17 in the rightward closing direction via the roller 22. As shown in FIG. 1, the rollers 22 are a pair and do not hinder the linear movement of the operating rod 17.

If an oil leak were to occur in the closed state shown in FIG. 1, a leftward force would be applied to the operating rod 17 via the operating rod 15. However, the compression spring 23 selected to oppose this acting force
Since the engaging member 19 is pressed to the left via the roller 22, the operating rods 15 and 17 are not driven to the left, so that the closed state can be maintained.

However, when a shutoff command is given and the oil in chamber C is collected, the leftward force applied to the operating piston 6 is much larger than the external force applied during the oil leak mentioned above. , the engaging member 19 is the roller 2
While pushing up 2, it moves to the left and enters the blocking state. At this time, when the engaging member 19 passes the roller 22, the roller 22 descends toward the operating rod 17 until the collar 20a in FIG. will be prevented. Therefore, the roller 22 does not come into contact with the outer peripheral surface of the operating rod 17. In particular, the outer peripheral surface of the operating rod 17 at this time is
It is a sealing surface that maintains airtightness by the roller 22, and is not damaged by the roller 22, so that a perfect sealing surface can be maintained. In other words, since the seal surface of the operating rod 17 can be protected by regulating the position of the roller 22, the position holding mechanism can be protected by the seal 3.
It can be configured in the vicinity of 1.

In the above embodiment, the position holding mechanism is arranged on the operating rod 17 side, but it can also be arranged on the operating rod 15 side. However, in this case, it is necessary to prevent the engaging member formed on the operating rod 15 from passing through the seal 30, so the operating cylinder 16
The position holding mechanism is configured to be spaced apart from the right end by the distance required for the opening/closing operation. Further, although only one pair of rollers 22 is provided, three or more may be provided on the outer periphery of the engaging member 19, and the shape of the engaging member 19 is not limited to the illustrated example, and may be formed by rolling elements such as the rollers 22. Any shape is acceptable as long as it converts into force in the input direction. Furthermore, the roller 22
A bolt 25 is provided to fix the engaged state of the engagement member 19 and the movable frame 20 is guided by the bolt 25. However, on the inner surface of the position holding mechanism guide 27, a predetermined length in the moving direction of the movable frame 20 is provided. A groove is cut and a protrusion that moves within this groove is attached to the movable frame 2.
A protrusion regulating means fixed at 0 may also be used.

〔Effect of the invention〕

As explained above, the present invention disposes a compression spring in the radial direction of the operating rod, and converts this spring force into a force for holding the operating rod in the closing direction by means of an engaging member. Compared to a spring mechanism, the size in the radial direction can be restricted and the position holding mechanism can be made smaller.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a hydraulic operating device for a circuit breaker according to an embodiment of the present invention, Fig. 2 is a side view from the left side of Fig. 1, and Fig. 3 is an enlarged sectional view of the main part of Fig. 1. ,
Figure 4 is a sectional view taken along the - line in Figure 3;
The figures are a sectional view taken along the - line in Fig. 3, Fig. 6 is a vertical sectional view of a conventional hydraulic operating device for a circuit breaker, and Fig. 7 is a longitudinal sectional view of a conventional circuit breaker hydraulic actuator.
The figure is an enlarged front view of the main part of FIG. 6. 3... Operating valve, 6... Operating piston, 15,1
7... Operating rod, 16... Operating cylinder, 19
...Engagement member, 20...Movable frame, 22...
Roller, 23...compression spring, 27...position holding mechanism case.

Claims (1)

[Scope of Claims] 1. An operating piston is slidably disposed within an operating cylinder to constitute an operating valve, and an operating rod connected to either side of the operating piston is led out from the operating cylinder to shut off the valve. Connected to the mover of the section,
In a hydraulic operating device for a circuit breaker configured to hold the operating piston in a closed position by a position holding mechanism, an operating rod connected to either one surface of the operating piston and located outside the operating cylinder. A rolling element is provided on the outer periphery of the operating rod, which is biased by a compression spring arranged in the radial direction of the operating rod, and comes into contact with the rolling element to convert the force of the compression spring into the direction of closing the operating rod. A hydraulic operating device for a circuit breaker, characterized in that the engaging member is connected to the operating rod to constitute the position holding mechanism. 2. The device described in claim 1 above, characterized in that the operating rod connected to the engaging member is connected to the other surface of the operating piston to which the operating rod connected to the mover is fixed. Hydraulic operating device for circuit breakers. 3. The circuit interrupter according to claim 1, wherein the position holding mechanism has a protruding regulating means for regulating the position of the rotor so that it does not come into contact with the outer peripheral surface of the operating rod. Dexterous hydraulic actuator.