JPH01296523A - Buffer type gas-blasted circuit breaker - Google Patents

Abstract

PURPOSE:To obtain a small-sized energy saving type gas-blasted circuit breaker by further utilizing the energy used for a damper action among the driving energy as the arc-extinguishing energy. CONSTITUTION:The pressure in a buffer chamber 11 is not increased so much at the initial stage of cutoff, thus the gas expansion stream from an arc 13 becomes a stream 12b through the hollow section 5b of a rod 5 and quickly flows into the buffer chamber 11. The expansion stream 12c can effectively give heat to the gas in the buffer chamber 11 because the stream 12b due to heat is very large. This is added to the primary compression action of a buffer piston 7 and a buffer cylinder 6, thus the pressure in the buffer chamber 11 is increased. A nozzle 10 is sufficiently opened, thus the current can be cut off. The heat taken into the buffer chamber 11 is nearly uniformly dispersed in the cylinder 6, the high pressure rise is continued until the cutoff action is completed. On the other hand, the step section 6a of the cylinder 6 and the step section 7b of the piston 7 are coupled in the later stage of the cutoff action, the buffer chamber 11 sprays the high-pressure gas stream to the arc 13 to perform an arc-extinguishing action.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an improvement of a puffer type gas circuit breaker which is made smaller by effectively utilizing arc energy.

(Prior Art) A conventional circuit breaker has a configuration as shown in FIG. Further, 2 is a movable contact portion, and a puffer cylinder 6, a movable arc contact 8, a movable energizing contact 9, and an insulating nozzle 10 are fixed to hollow drive rods 1 to 5. In the movable contact portion 2, the puffer cylinder 6 forms a puffer chamber 1 with a puffer screw 1-7 fixed to a fixed portion (not shown). Further, in the movable part contactor part 2, the hole 5a communicating between the hollow part 5b of the driving rod 5 and the outside thereof is connected to the hollow part 5b of the driving rod 1 and the puffer at the beginning of the cutoff operation, as shown in FIG. It is added so that the inside of the chamber 11 is communicated with each other.

This hole 5a is configured to communicate with the hollow part 5b of the drive rod 5 and the surrounding gas space when it passes through the inner diameter end 1al of the puffer screw 1hen 7 in the latter half of the shutoff operation.The hollow part of the drive rod 5 A protrusion 5c is provided at the rear end of 5b to smoothly guide the gas flow in the axial direction to the hole 5a.

The drive rod 5 is connected to a lever 23 that transmits the driving force from the drive mechanism 22 via a ring mechanism 21, and this lever 23 is further connected to an oil damper 24 to control the speed and operating characteristics in the latter half of the shutoff operation. ing.

(Problem to be solved by the invention) However, since the cut-off damper mechanism is located on the driving part side, a large buckling force acts on the connecting ring part in the latter half of the cut-off operation, and especially insulators such as insulating rods are It was necessary to increase the area. In addition, due to looseness and elongation of the connecting pins and connecting members, a large open loaf may occur on the arc extinguishing chamber side. For this reason, there was a risk that the insulating support would be damaged by the impact force caused by the metal collision of the parts in the arc extinguishing chamber.

Furthermore, the use of oil dampers was expensive.

An object of the present invention is to eliminate the use of a damper on the drive unit side.

To provide a mechanically reliable and inexpensive circuit breaker by reducing the amount of opacity of a movable part of an arc extinguishing chamber by using a puffer cylinder in the arc extinguishing chamber also as a gas damper chamber.

[Structure of the invention]

(Means for solving the problem) Provide a step between the puffer piston and the puffer cylinder so that the difference in their inner and outer diameters is small. They are characterized in that they are configured to fit into each other in the latter half of the interrupting operation.

(Function) When the puffer screws 1 to 1 and the stepped portion of the puffer cylinder begin to fit together in the latter half of the shutoff operation, the puffer chamber is divided into two.

Of the two chambers, the chamber that communicates directly with the nozzle portion continues to function as a puffer chamber.

On the other hand, the gas in the chamber that does not directly communicate with the nozzle part is discharged into the puffer chamber only through the gap between the fitting part of the puffer piston and the puffer cylinder, but because this gap is small, the pressure in the chamber rises rapidly, causing a shutoff operation. acts as a damper, contributing to deceleration. Note that the pressure-enhanced gas discharged from the damper chamber into the puffer chamber contributes to further increasing the pressure within the puffer chamber, resulting in improved arc-extinguishing performance. In this way, the energy used in the damper is not lost and is used to extinguish the arc, so there is no wastage of energy.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2.

Figure 1 shows the initial state of the arc extinguishing chamber shutoff operation according to the present invention.
FIG. 2 shows the state in the latter half of the shutoff operation.

In FIG. 1, reference numeral 1 denotes a fixed contact section, which is composed of a fixed arc contact 4 and a fixed current-carrying contact 3. Reference numeral 2 denotes a movable contact portion, in which a puffer cylinder 6, a movable arc contact 8, a movable energizing contact 9, and an insulating nozzle 10 are fixed to a hollow drive rod 5. In the movable contact portion 2, the puffer cylinder 6 forms a puffer chamber 11 with a puffer piston 7 fixed to a fixed portion (not shown). In addition, in the movable part contactor part 2, a hole 5 that communicates between the hollow part 5b of the drive rod 5 and the outside thereof
As shown in the figure, a is processed so that the hollow portion 5b of the drive rod 5 and the inside of the puffer chamber 11 communicate with each other in the initial stage of the shutoff operation.

The puffer cylinder 6 has a stepped portion 6a on the inside thereof,
Further, the puffer piston 7 has a stepped portion 7b on its outer side, and these two stepped portions are configured to have a slight dimensional difference.

As shown in FIG. 2, the hole 5a is configured to communicate with the hollow portion 5b of the drive cylinder 1-5 and the surrounding gas space when it passes the inner diameter end 7a of the puffer piston 7 in the latter half of the shutoff operation. . A convex portion 5C is provided at the rear end of the hollow portion 5b of the drive rod 5 to smoothly guide the flow of gas in the axial direction to the hole 5a.

The stepped portions of the puffer piston 7 and the puffer cylinder 6 fit into each other in the latter half of the shutoff operation, and the puffer chamber 11 is in direct communication with the nozzle portion 10 ], ], tv
and the damper 11b which does not communicate with each other.

The drive rod 5 is connected to the drive mechanism 22 via the connecting ring part 21.
It is connected to the lever 23 of. In the figure, SP is the cross-sectional area of the puffer chamber 11a, SD is the cross-sectional area of the damper chamber 11b, VI'O is the volume of the puffer chamber 11a at the mating position, and V
OO represents the volume of the damper chamber 11b, and A represents the fitted length.

Next, the operation of this embodiment will be explained with reference to FIGS. 1 and 2.

As described above, FIG. 1 shows the initial state of the shutoff operation.

In this state, the arc 13 is generating a large amount of heat, but the nozzle 10 has not yet opened sufficiently, so there is no ability to shut it off. Also, in the disconnected state shown in the figure, the hole 5a of the drive rod is still connected to the end 7 of the puffer piston 7.
a), the hole 5a communicates with the inside of the puffer chamber 11.

On the other hand, at such an early stage of shutoff, the puffer chamber 11
Since the internal pressure has not increased much, the expanding gas flow from the arc 13 becomes a flow 12b passing through the hollow portion 5b of the rod 5, and rapidly flows into the puffer chamber 11.

Expanded flow 12c also occurs in the conventional puffer type gas circuit breaker, but flow 12b due to heat is very large and can therefore effectively impart heat to the gas in puffer chamber j1. Since this is added to the original compression operation of the puffer screw 1-7 and the puffer cylinder 6, the pressure inside the puffer chamber 11 increases.

The hole 5a then passes through the end 7a of the puffer piston 7 and communicates with the surroundings, as shown in FIG.

Therefore, the hollow portion 5b of the drive rod 5 is open to the surrounding gas, and heat from the arc is released. In such a state, the nozzle 10 is already fully opened and is in a state where it can cut off the current, so it is in a state where the current can be cut off.

Since the heat taken into the puffer chamber 11 is distributed almost uniformly within the cylinder, the high pressure rise continues until the shutoff operation is completed. Therefore, high-speed gas flow is blown onto the arc for a long period of time, so high breaking performance can be obtained.

On the other hand, in the latter half of the shutoff operation, the stepped portion 6a of the puffer cylinder
and the stepped portion 7b of the puffer piston fit together to separate the puffer chamber 11 into a puffer chamber 1a and a damper chamber 11b.

Due to the compression operation of the puffer cylinder 6 and the puffer piston 7, the puffer chamber 1.1a sprays a high pressure gas flow onto the arc 13 through the nozzle 10, thereby extinguishing the arc.

On the other hand, the damper chamber 11b has only a gap between the stepped portion 7b of the puffer piston 1 and the stepped portion 6a of the puffer cylinder, so that the internal pressure of the damper chamber 11b increases rapidly with the shutoff operation. . Drive mechanism 22
If the cross-sectional area SD and compression length A of the damper chamber 11b are appropriately selected with respect to the driving energy of and the weight of the movable part of the cut-off part,
The shutoff operation can be conveniently braked by the reaction force of the gas pressure increased by the gas compression action.

Further, the gas in the damper chamber 11b, which has become high in pressure due to compression, is discharged into the puffer chamber 11a through the gap between the fitting portion of the puffer piston 7 and the puffer cylinder 6, increasing its pressure and contributing to the arc extinguishing action.

The drive mechanism side 22 is stopped by braking on the arc extinguishing chamber side.

In this way, according to this embodiment, not only is the device compact and energy-saving by using the energy of the arc for arc extinguishing, but also the puffer chamber can also be used as a gas damper chamber, so that the driving energy can be reduced to the final level. It is converted into arc-extinguishing energy, making it even more energy-saving. On the other hand, since only the tensile force is applied to the connecting ring portion during the breaking operation, the cross-sectional area of the insulating rod, which was large due to buckling, can be reduced, making it possible to reduce weight and cost. Additionally, the amount of overstroke on the arc extinguishing chamber side due to backlash in the link pin or connecting portion can be limited, and a highly reliable circuit breaker can be provided. Furthermore, since an oil damper is not required, the driving section can be simplified and the cost can be reduced.

In addition, exactly the same effect can be obtained when the three phases of the arc extinguishing chamber are driven by one drive source. Furthermore, similar effects can be obtained by applying the present invention even if a hydraulic mechanism or a pneumatic operating mechanism is used as the drive source.

〔Effect of the invention〕

According to the present invention, the energy used for the damper action out of the driving energy can be further utilized as arc-extinguishing energy, so a compact and energy-saving circuit breaker can be obtained. Since the arc-extinguishing chamber side has a shutoff damper effect, the connecting link part receives only the tensile action, making it lighter in weight, and the play in the link part does not affect the stopping position of the arc-extinguishing chamber, resulting in reliable arc-extinguishing action. A circuit breaker with mechanical properties is obtained. Furthermore, by omitting the damper on the drive section side, an inexpensive circuit breaker can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a puffer-type gas circuit breaker showing an embodiment of the present invention at the early stage of the breaking operation, FIG. 2 is a cross-sectional view of the puffer-type gas circuit breaker shown in FIG. 1 at the latter stage of the breaking operation, and FIG. FIG. 2 is a sectional view showing the initial stage of the breaking operation of a conventional puffer type gas circuit breaker. 1. Fixed contact part, 2. Movable contact part, 3. Fixed current-carrying contact, 4. Fixed arc contact, 5. Drive rod, 5a Drive rod hole, 5b Drive rod hollow part, 5C... Convex portion, 6... Puffer cylinder, 6a... Puffer cylinder step, 7... Puffer piston, 7a Puffer piston end, 7b... Puffer piston step, 8... Movable arc contact, 9... Movable current-carrying contact,
10...Insulating nozzle, 11...Puffer chamber, 1
] a puffer room, 11. b...damper room, 1
2. Gas flow, +2a, 12b, 12c Hot gas flow, 13 Arc, 21 Connecting link section, 22. Drive mechanism section, 23. Lever, 24
oil damper. Agent Patent Attorney Noriyuki Chika Yudo Ken Daishimaru

Claims (2)

[Claims] (1) By compressing the puffer chamber consisting of a puffer piston and a puffer cylinder provided in the movable contact part, the gas is compressed and the arc generated between the fixed and movable arc contacts is sprayed and cooled. - In a puffer type gas circuit breaker that extinguishes an arc, the puffer cylinder and the puffer piston are each provided with a stepped portion, and in the early stage of the shutoff operation, the puffer chamber forms one space, and in the latter half of the shutoff operation, each of the above By fitting the stepped portions into each other with a minute gap, the puffer chamber is divided into two, a second puffer chamber and a damper chamber, and the second puffer chamber continues its arc extinguishing action, while the damper chamber is a puffer-type gas circuit breaker that slows down and stops the circuit breaker's interrupting operation using the reaction force caused by the rise in internal gas pressure due to compression. (2) A plurality of holes are provided in the hollow part of the operating rod that drives the puffer cylinder, and at the initial stage of the shutoff operation, the hollow part of the operating rod and the puffer chamber constituted by the puffer cylinder and puffer piston are connected to each other through the holes. Claim 1, wherein the hollow part of the operating rod and the outside of the puffer chamber are communicated through the hole in the latter half of the blocking operation.
Puffer type gas circuit breaker as described.