JPH08203393A - Control mechanism of vacuum circuit breaker - Google Patents

Abstract

PURPOSE: To provide a control mechanism of a vacuum circuit breaker which can deal with an increase in capacity by a minimum of parts changeover. CONSTITUTION: In the control mechanism of a vacuum circuit breaker which uses a cutoff spring in a tripping operation and stores the energy of the spring through the action of the link mechanism of a toggle joint, a roller 17 is mounted on a pin 19 at a predetermined link connecting point in such a way that it can be joined to a trip hook 10, and a roller that locks with a closing cam is mounted on another pin at the adjacent link connecting point. The pivot point of a link 12A which shares loads with the junction of the trip hook 10 and the roller 17 is moved from the conventional position toward the trip hook 10 by the required angle (about 15 deg.). The movement of the link pivot point decreases loads working on both the trip hook and the roller, and provides sufficient durability to resist increase in the cutoff spring force, etc., so that an increase in capacity can be dealt with by a minimum of parts changeover.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating mechanism of a vacuum circuit breaker which utilizes a spring force for a tripping operation, and more particularly to an improvement of its link mechanism.

[0002]

2. Description of the Related Art An example of the structure of an operating mechanism of a vacuum circuit breaker is shown in FIG.
As shown in FIG. 3 is a tripped state, and FIG. 4 is a closed state. In the figure, 1 is a vacuum interrupter (VI), 2 is an insulating rod, 3 is a pressure contact spring that gives a pressure contact force necessary for the contact of VI1, 4 is a blocking spring, 5 is a piston-shaped operation plate, and 6 is this operation plate 5 A guide member of a cylindrical shape, 7 a ring for smoothing the movement of the operation plate 5, 8 a stopper for the operation plate, 9 an electromagnet for tripping, 10 a trip hook,
Reference numeral 11 is a closing cam, 12 to 16 are links, 17 and 18 are rollers, 19 to 23 are pins, 24 is a link stopper, 25 is a trip hook return spring, and 26 is a link return spring. Links 12-16 and pins 19-
Reference numeral 23 is a member for forming a link mechanism of a toggle joint, and links 12 to 15 are connected by pins 19 to 21 to pivotally attach an end portion on the link 12 side to a fixed point,
The end portion on the link 15 side is pivotally attached to the operation plate 5. One end of the link 16 is also connected to the connection point of the links 14 and 15, and the other end of the link 16 is pivotally attached to a fixed point. Pins 22 and 23 are used at the pivot points of the links 12 and 16. A roller 17 is attached to the pin 19 at the connecting point of the links 12 and 13 so that the roller 17 can be joined to the trip hook 10.
Further, a roller 17 interposed between the closing cam 11 and the stopper 24 is attached to the pin 20 at the connecting point of the links 13 and 14.

The closing operation is performed as follows. If a closing command is issued while the circuit breaker is open, the closing cam 11
Rotates and the roller 18 is pressed. Along with this, the link 12 rotates counterclockwise, and the roller 17 and the trip hook 10 are engaged. Link 13 with this engagement point as a fulcrum
Rotates counterclockwise. This allows links 14,1
5 moves upward, and the operation plate 5 is pushed up. Therefore, the contact of VI1 comes into contact, and the necessary pressure contact force is applied by the pressure contact spring 3. At this time, in the link mechanism, the roller 18 is engaged with the stopper 24, and the closed state is maintained.

The tripping operation is performed as follows. When a break command is issued while the breaker is closed, the tripping electromagnet 9 operates and the trip hook 10 rotates counterclockwise to disengage the roller 17. Links 12, 1
The pin 19 at the connection point of 3 is applied with the force of the cutoff spring 4, the pressure contact spring 3, etc., and the trip hook 10 and the roller 17 are connected.
The link 12 rotates counterclockwise at the same time as the engagement of is disengaged, and the links 13 to 15 rapidly descend. That is, the operation plate 5 is rapidly pulled down, and the contact of VI1 is opened. After this tripping operation, the link 12 is reversed by the return spring 26, and the trip hook 10 is also reversed by the return spring 25. This resets the link mechanism.

[0005]

As described above, in the operating mechanism of the circuit breaker, since the spring force is utilized for the tripping operation and the like, the joint between the roller 17 and the trip hook 10 and the link 12 during the closing operation. A very large load is applied to the pivot point (pin 22) of 1 due to the influence of the breaking spring force and the pressure contact spring force. In this state, the positional relationship is as shown in FIG. That is, the angle between the trip hook 10 and the link 12 is α, the angle between the links 12 and 13 is β, and the angle between the link 13 and the trip hook 10 is γ. Link 13
A load (breaking spring force + pressure contact spring force) F is applied from the side, and acts as a load F ₁ on the trip hook 10 side and a load F ₂ on the link 12 side, respectively.

The acting loads F ₁ and F ₂ become more remarkable as the capacity of the circuit breaker increases. This is because in the case of a large capacity circuit breaker, the breaking spring force required for the VI breaking speed and the pressure contact force required for the VI contact point must be increased. Therefore, when applied to a large capacity circuit breaker, the trip hook 10 is
Since the surface pressure and the stress of the pin 22 at the pivot point supporting the link 12 are larger than the allowable stress of the material, reinforcement is required, but the size of the circuit breaker is also limited, and the link mechanism is drastically reduced. It is difficult to change.

Therefore, an object of the present invention is to solve the above problems and provide an operating mechanism of a vacuum circuit breaker capable of dealing with an increase in capacity with a minimum change in parts.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a roller is attached to a pin at a link connecting point in a link mechanism of a toggle joint so that the roller can be joined to a trip hook. In the operating mechanism of the vacuum circuit breaker, which receives the force of the breaking spring, the pressure contact spring, etc. at the pivot point of the end, the pivot point of the link end is moved to the trip hook side by the required angle.

[0009]

[Function] The force of the breaking spring, the pressure contact spring, etc. is applied to the joint between the trip hook and the roller and the pivot point of the link end. The acting loads at both points are smaller than before the movement of the link pivot point, and the durability is sufficient even when used in a large capacity circuit breaker. Also, the function of the link mechanism is maintained. Therefore, it can be applied with a minimum change of parts such as exchanging one link.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings.

FIG. 1 shows an embodiment (main part) of the operating mechanism of the vacuum circuit breaker according to the present invention. In the figure, 10 is a trip hook, 12A and 13 are links, and 19 is a link 12A, 1
It is the pin used to connect 3 and this pin 19 has a roller 17
Is attached so that it can be joined to the trip hook 10. The end of the link 12A is pivotally attached at a fixed point. This link 1
The pin 22 is used for the pivotal attachment of 2A. The pivot point of the link 12A is the trip hook 10 from the previous position indicated by the broken line.
It is moved to the side by x °. Thereby, the angle between the trip hook 10 and the link 12A is (α-x),
The angle between 2A and 13 is (β + x), and the angle between the link 13 and the trip hook 10 is γ.

The relationship between the loads F, F ₁ and F ₂ is as shown in FIG. 2 in vector display and is expressed by the following equation. However, here, the respective angles are α, β, γ.

[0013]

[Equation 1]

Here, the acting loads F ₁ and F ₂ before and after moving the link pivot point are calculated and compared. First, with the settings of α = 108 °, β = 134 °, γ = 118 ° before movement,
When F = 2000kgf,

[0015]

[Equation 2]

[0016] The link pivot point is x ° (= 15 °)
When moving to the trip hook 10 side, α = 93
°, β = 149 °, γ = 118 °, F = 2000
When kgf,

[0017]

(Equation 3)

[0018]

As described above, the loads F ₁ and F ₂ are smaller when the link pivot point is moved, and when applied to a large capacity breaker, even if most of the parts are the same, it is sufficient. Will have excellent durability. In other words, it can be applied with a minimum change of parts such that one link is replaced.

It should be noted that x = 15 ° is a movement angle close to the limit at which the desired function of the link mechanism can be substantially maintained without affecting other structures, and the movement is within the range satisfying the following conditions. The angle can be appropriately selected.

[0021]

As described above, according to the present invention, the link pivot point, which shares the load due to the breaking spring, the pressure contact spring, etc., with the junction between the trip hook and the roller, is moved to the trip hook side to reduce the applied load. Since it is designed to reduce the number of parts, even when it is applied to a large capacity circuit breaker, most parts such as trip hooks, rollers, and pins can be used as they are, and the number of changed parts can be minimized. it can.

[Brief description of drawings]

FIG. 1 is an explanatory view of a main part configuration showing an embodiment of an operating mechanism of a vacuum circuit breaker according to the present invention.

FIG. 2 is a vector display diagram of a load acting on a link mechanism in an operating mechanism.

FIG. 3 is a structural explanatory view (triggered state) showing a structural example of an operating mechanism of a vacuum circuit breaker.

FIG. 4 is a structural explanatory view (closed state) showing a structural example of an operating mechanism of a vacuum circuit breaker.

FIG. 5 is a structural explanatory view showing a load sharing section of the link mechanism in the operating mechanism of the vacuum circuit breaker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... VI 3 ... Press-contact spring 4 ... Breaking spring 10 ... Trip hook 12A, 13-16 ... Link 17, 18 ... Roller 19-23 ... Pin

Claims (1)

[Claims] A roller is attached to a pin at a link connection point in a link mechanism of a toggle joint so that the roller can be joined to a trip hook, and a breaking spring is provided at a joint portion between the trip hook and the roller and a pivot end of a link end during a closing operation. An operating mechanism of a vacuum circuit breaker that receives a force of a pressure contact spring or the like, wherein a pivot point of a link end is moved to a required angle trip hook side.