JPH0714533U - Gas circuit breaker - Google Patents

Abstract

(57) [Summary] [Purpose] To make the operation of the check valve stable in the thermal puffer type gas circuit breaker that also uses the suction puffer. In a hot puffer-type gas circuit breaker that also uses a suction puffer, a check valve 11 provided in the suction puffer chamber 9 has a hinged opening / closing structure, and a spring that normally urges the check valve in a direction to close the valve. 12 is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a gas circuit breaker, and more particularly to a thermal puffer type gas circuit breaker that also uses a suction puffer.

[0002]

[Prior art]

 A thermal puffer type gas circuit breaker that also uses a suction puffer has been known as an arc extinguishing technology for gas circuit breakers. This will be described with reference to FIG. The left half of Fig. 3 shows the closed state of the circuit breaker, and the right half shows the state of the circuit breaker during the breaking operation.

In the figure, 2 is a pressure raising chamber, 3 is a fixed contactor, 4 is a nozzle, 5 is a coil, 6 is an arc runner, and 7 is a movable contactor. Further, the outer wall 1 of the pressurizing chamber 2 and the cylinder 8 provided on the movable contact 7 form a suction puffer chamber 9. The cylinder 8 is provided with an opening 10 and a check valve 15 for closing the opening 10. The check valve 15 is normally urged toward the opening 10 by a spring 16 so as to close the opening 10.

When the movable contact 7 is moved downward, the suction puffer chamber 9 has an increased internal volume. At this time, the check valve 15 closes the opening 10 by the pressure of the spring 16 and the gas pressure outside the suction puffer chamber 9, so that the pressure inside the suction puffer chamber 9 becomes low. On the contrary, when the pressure inside the suction puffer chamber 9 becomes higher than the pressure outside, the check valve 15 releases the pressure inside the suction puffer chamber 9 to the outside as shown in the right half of the figure.

Next, the operation of the thermal puffer type gas circuit breaker that also uses the suction puffer will be described. When the left half of the drawing is energized, a current flows between the fixed contactor 3 and the movable contactor 7 in contact with each other. When the circuit breaker is shut off, the movable contact 7 is moved downward in the figure by an operating mechanism (not shown). When the movable contactor 7 separates from the fixed contactor 3, the current commutates to the path of the coil 5 and the arc runner 6, and the arc B is generated between the arc runner 6 and the movable contactor 7. Then, the arc B is rotationally driven at high speed around the illustrated central axis by the magnetic field generated by the current flowing through the coil 5.

As the arc B rotates inside the booster chamber 2, the gas inside the booster chamber 2 is heated to a high temperature and the gas pressure rises. Further, the rotation of the arc B means extinguishing the arc by relatively blowing the gas onto the arc B. When the movable contactor 7 is inside the booster chamber 2, the arc extinguishing action by this magnetic drive is performed. On the other hand, the downward movement of the movable contact 7 reduces the gas pressure inside the suction puffer chamber.

After that, when the movable contact 7 moves further downward and the tip of the movable contact 7 comes off the nozzle 4 of the pressurizing chamber 2, the high-pressure gas inside the pressurizing chamber 2 has a low pressure. As shown by an arrow C, it is rapidly ejected into the inside of the nozzle 9 through the space between the nozzle 4 and the movable contactor 7. This gas flow causes an arc extinguishing action by a heat puffer that blows out the arc B generated between the arc runner 6 and the movable contact 7.

At this time, when the inside of the suction puffer chamber 9 becomes higher in pressure than the outside due to the high-pressure gas discharged from the pressurizing chamber 2, the check valve 15 moves against the force of the spring 16 and is indicated by an arrow D. In addition, the high pressure gas from the pressurizing chamber 2 is quickly discharged to the outside. Further, when the breaking current is in the small current region, the gas pressure in the booster chamber 2 is not high enough to blow out the arc B. In this small current region, when the movable contact 7 is disengaged from the booster chamber 2, the suction puffer chamber 9, which has a low pressure, sucks the gas inside the booster chamber 2. Then, the gas is blown to the arc B through the narrow gap between the nozzle 4 and the movable contact 7 to extinguish the arc by the suction puffer.

[0009]

[Problems to be solved by the device]

 In the above-mentioned conventional device, the pressure when the check valve 15 operates is dynamic, so that the pressure distribution is not necessarily uniform over the entire check valve 15. Therefore, the check valve 15, which is only supported by the spring 16 in the vicinity of the central portion, may move in an oblique state because only a portion to which strong pressure is applied tends to move downward. As described above, when the check valve 15 moves in a slanted state, the check valve 15 is twisted between the check valve 15 and the movable contact 7, and smooth operation cannot be performed. Therefore, in the worst case, the check valve 15 may not operate and the gas flow for interrupting the current may not be obtained.

An object of the present invention is to make the operation of the check valve stable in a thermal puffer type gas circuit breaker that also uses a suction puffer.

[0011]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention has a check valve provided in a suction puffer chamber with a hinged opening / closing structure in a thermal puffer type gas circuit breaker that also uses a suction puffer, and a continuous valve is provided for the check valve. A spring that urges in the closing direction is provided.

[0012]

[Action]

 According to the above-mentioned means, since the check valve rotates about the hinge axis during its operation, the locus of motion with respect to the movable contact is always constant, and the movable contact does not twist. It never happens. Therefore, when high-pressure gas is discharged, even if pressure is not evenly applied to the check valve, the high-pressure gas is discharged by performing a smooth rotational movement to prevent the arc extinguishing action due to the thermal puffer effect. It does not become.

[0013]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a cross section of one embodiment of the present invention and shows a cross section of a main part of a thermal puffer type gas circuit breaker. The illustrated blocking unit is housed together with SF6 gas in a container (not shown). The left half of the figure shows the closed state of the circuit breaker, and the right half shows the state when the circuit breaker is closed.

In the figure, reference numeral 1 denotes an outer wall that constitutes a booster chamber 2 in which a nozzle 4 is formed, and a fixed contact 3, a coil 5, and an arc runner 6 are housed in the booster chamber 2. Further, the outer wall 1 of the pressurizing chamber 2 and the cylinder 8 provided in the movable contact 7 form a suction puffer chamber 9. The outer wall 1 and the cylinder 8 are in intimate contact with each other, and when the movable contact 7 moves downward, the volume of the suction puffer chamber 9 formed by the outer periphery of the outer wall 1 and the cylinder 8 increases, and the gas inside the chamber increases. Reduce pressure.

The cylinder 8 is provided with an opening 10 and a check valve 11 for closing the opening 10. As shown in FIG. 2, the check valve 11 has a hinge structure in which two semicircular plates rotate about a shaft 12 fixed to the movable contact 7, and is fixed to the movable contact 7. A spring 13 attached to the shaft 14 is biased from the outside. The check valve 11 normally closes the opening 10 and rotates against the pressure of the spring 13 when the pressure inside the suction puffer chamber 9 increases, and as shown by the arrow D in the figure, the inside of the suction puffer chamber 9 is closed. Gas is discharged to the outside of the cylinder 8 through the opening 10.

Next, the operation of the thermal puffer type circuit breaker that also uses the suction puffer will be described. When the left half of the drawing is energized, the fixed contactor 3 and the movable contactor 7 come into contact with each other, and a current flows between the two. When the circuit breaker is shut off, the movable contact 7 is moved downward in the figure by an operating mechanism (not shown). When the movable contactor 7 separates from the fixed contactor 3, the current commutates to the path of the coil 5 and the arc runner 6, and the arc B is generated between the arc runner 6 and the movable contactor 7.

Then, the arc B is rotationally driven at high speed around the illustrated central axis by the magnetic field generated by the current flowing through the coil 5. As the arc B rotates inside the booster chamber 2, the gas inside the booster chamber 2 is heated to a high temperature and the gas pressure is increased. Further, the rotation of the arc B means that the gas is relatively blown to the arc B to extinguish the arc. When the movable contactor 7 is in the booster chamber 2, the magnetically driven arc extinguishing action is performed.

On the other hand, the downward movement of the movable contact 7 reduces the gas pressure inside the suction puffer chamber 9. After that, when the movable contactor 7 moves further downward and the tip of the movable contactor 7 comes off the nozzle 4 of the pressurizing chamber 2, the high-pressure gas inside the pressurizing chamber 2 is in the low-pressure suction puffer chamber 9 inside. , And suddenly ejects as shown by an arrow C through the space between the nozzle 4 and the movable contactor 7. By this gas flow, an arc extinguishing action is performed by a thermal puffer effect that blows out the arc B between the arc runner 6 and the movable contact 7.

At this time, when the inside of the suction puffer chamber 9 becomes higher in pressure than the outside due to the high-pressure gas discharged from the pressurizing chamber 2, the check valve 11 resists the force of the spring 13 so that the hinge shaft 12 is centered. It rotates and separates from the opening 10 and sucks the high pressure gas in the puffer chamber 9 to the outside as shown by an arrow D. By the operation of the check valve 11, the flow of the gas that blows out the arc B smoothly flows.

When the breaking current is in the small current region, the gas pressure in the booster chamber 2 is not high enough to blow out the arc B. In this small current region, when the movable contact 7 is disengaged from the booster chamber 2, the suction puffer chamber 9, which has a low pressure, sucks gas from the inside of the booster chamber 2. As a result, the gas flow is extinguished by the suction puffer, which blows the gas to the arc B through the narrow gap between the nozzle 4 and the movable contactor 7.

In the above-described operation, the check valve 11 closes the opening 10 by the gas pressure of the spring 13 and the outside when the pressure in the suction puffer chamber 9 is made low, and makes the pressure in the suction puffer chamber 9 low. Further, when the high-pressure gas in the booster chamber 2 is discharged into the suction puffer chamber 9 and the gas pressure inside the suction puffer chamber 9 becomes high, the hinge shaft 12 is rotated against the force of the spring 13. After that, the high pressure gas in the suction buffer chamber 9 is quickly discharged to the outside from the opening 10.

Since the check valve 11 rotates about the hinge shaft 12 during its operation, the locus of movement with respect to the movable contact 7 is always constant. Therefore, when the high-pressure gas is discharged, even if the check valve 11 is not evenly pressured, the movable contact 7 is not twisted and a smooth rotational movement is performed. It discharges high-pressure gas and does not interfere with the arc extinguishing effect of the thermal puffer effect.

[0023]

[Effect of device]

 According to the present invention, a check valve with stable operation can be obtained in a hot puffer type gas circuit breaker that also uses a suction puffer.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a gas circuit breaker of the present invention.

FIG. 2 is a bottom view of the check valve as seen from the direction of arrow AA in FIG.

FIG. 3 is a sectional view of a conventional gas circuit breaker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outer wall 2 ... Pressure rising chamber 3 ... Fixed contact 4 ... Nozzle 5 ... Coil 6 ... Arc runner 7 ... Movable contact 8 ... Cylinder 9 ... Suction puffer chamber 10 ... Opening 11 ... Check valve 12 ... Shaft 13 ... Spring

Claims (1)

[Scope of utility model registration request] 1. A thermal puffer type gas circuit breaker that also uses a suction puffer, wherein a check valve provided in the suction puffer chamber has an opening / closing structure with a hinge, and a spring that constantly urges the check valve in a direction to close the valve. A gas circuit breaker characterized by being provided with.