JP2001155595A - Buffer gas breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a buffer gas breaker capable of blowing arc-extinguishing gas to the arc effectively regardless of intensity of breaking current and timing of circuit opening. SOLUTION: Inside the buffer cylinder is partitioned to a mechanical buffer chamber in the buffer piston side and a thermal buffer chamber in the stationary contact side. A channel which communicates the mechanical buffer chamber and opens near the opening of the thermal buffer chamber is located around the movable contactor. The breaker is equipped with a check valve permitting the move of the arc-extinguishing gas from the mechanical buffer chamber to the thermal buffer chamber when the pressure of the gas in both chambers reaches the respective predetermined values, and a channel valve which turns open when the stationary contact and the movable contact between the channel and the mechanical buffer chamber are separated by a distance more than predetermined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puffer type gas circuit breaker, and more particularly to a structure for storing and blowing an arc-extinguishing gas.

[0002]

2. Description of the Related Art JP-A-61-285624 discloses that
In order to reduce the driving energy at the time of the opening operation, a storage pressure chamber and a puffer chamber are provided, and the first puffer chamber that communicates the puffer chamber with the nozzle immediately before the shutoff operation of the circuit breaker is completed, and between the storage pressure chamber and the first puffer chamber. A puffer type gas circuit breaker is described which is separated into a second puffer chamber which communicates with a storage pressure chamber through a provided hole.

[0003]

In the above arrangement, when the arc-extinguishing gas pressure in the storage pressure chamber is lower than that in the puffer chamber, a part of the arc-extinguishing gas released from the puffer chamber becomes a part of the storage pressure. There is a problem that the gas flows into the room and is consumed due to an increase in pressure there, and the amount of blowing the arc-extinguishing gas to the arc decreases. The present invention has been made to solve such a problem, and a puffer capable of blowing a sufficient amount of an arc-extinguishing gas to an arc even when the arc-extinguishing gas pressure in a storage pressure chamber is lower than that in a puffer chamber. The purpose is to realize a type gas circuit breaker.

[0004]

A puffer type gas circuit breaker according to the present invention divides the interior of a puffer cylinder into a mechanical puffer chamber on a puffer piston side and a thermal puffer chamber on a fixed contact side, and mechanically surrounds a movable contact. A flow path communicating with the puffer chamber and opening near the opening of the heat puffer chamber is provided, and when the arc-extinguishing gas in the mechanical puffer chamber and the heat puffer chamber reaches a predetermined pressure, the gas flows from the mechanical puffer chamber to the heat puffer chamber. A check valve allowing the movement of the arc-extinguishing gas,
A flow path valve is opened between the flow path and the mechanical puffer chamber when the fixed contact and the movable contact are separated by a predetermined distance or more.

Further, the flow path valve has a movable contact penetrating through the central portion thereof, is fixed to the puffer piston, and has an opening / closing rod having a small diameter at the puffer piston side and a large diameter at the other end as a valve body and a mechanical puffer chamber and a thermal puffer chamber. The inner diameter of the partition wall that separates the valve seat is used as a valve seat.

The interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contact side, and communicates with the mechanical puffer chamber between the puffer cylinder and an opening near the opening of the thermal puffer chamber. Flow path,
Between the mechanical puffer chamber and the flow path, the arc-extinguishing gas is moved only from the mechanical puffer chamber to the flow path. Between the mechanical puffer chamber and the thermal puffer chamber, only the heat is extinguished from the mechanical puffer chamber to the thermal puffer chamber. A check valve for moving the arc gas, and a valve opening / closing control device for closing the check valve when the arc-extinguishing gas in the heat puffer chamber is equal to or higher than a predetermined pressure; It is.

The interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contact side, and communicates with the mechanical puffer chamber between the puffer cylinder and an opening near the opening of the thermal puffer chamber. Flow path,
A flow valve that moves the arc-extinguishing gas from the inside of this flow path only to the arc generating section and a heat puffer chamber and an arc generating section when the arc generating section exceeds a predetermined arc-extinguishing gas pressure And a valve through which the arc-extinguishing gas moves.

Further, the interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contact side, and a flow which communicates with the mechanical puffer chamber between the movable contact and opens inside the thermal puffer chamber. And a flow path valve that moves the arc-extinguishing gas only from the mechanical puffer chamber to the thermal puffer chamber in this flow path, and an arc-extinguishing of the thermal puffer chamber according to the increase and decrease of the arc-extinguishing gas pressure in the thermal puffer chamber. The piston is provided with a piston for increasing or decreasing the amount of reactive gas.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a cross-sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a first embodiment of the present invention. FIG. (C) shows the middle to final stages of the interruption of the large current interruption, and (D) shows the opening operation of the small current interruption. Hereinafter, portions corresponding to the “puffer chamber” and the “reserved pressure chamber” used in the description of the conventional puffer circuit breaker described above are referred to as a “mechanical puffer chamber” and a “thermal puffer chamber”, respectively.

The portion shown in the figure is mounted in a casing filled with an arc-extinguishing gas (not shown). 1 is a fixed contact fixed to the casing, 2 is a movable contact arranged opposite to the fixed contact 1, and 3 is a piston rod fixed to the movable contact 2 and connected to a driving device (not shown). Reference numeral 4 denotes a puffer piston fixed to the casing, and 5 denotes a cylindrical shape, which is fixed to the puffer piston 4 and movably penetrates the movable contact 2 through a central through-hole.
An opening / closing rod in which a predetermined length portion on the side is formed to have a small outside diameter and a large outside diameter on the other end, 6 is a puffer cylinder in which a puffer piston 4 moves while sliding inside thereof in the axial direction,
Reference numeral 7 denotes a partition wall having a hole in which the large-diameter portion of the opening / closing rod 5 fits and moves without any gap at the center, 8 denotes a communication hole provided in the partition wall 7, and 9 denotes a nozzle fixed to the tip of the puffer cylinder 6. Reference numeral 10 denotes an inner cylinder which is fixed to the partition wall 7 and wraps around the movable contact 2 with a relatively small gap therebetween, and is opened near the end of the movable contact 2 on the fixed contact 1 side, and 11 is a communication hole. 8 is a valve that opens and closes. The internal space 50 defined by the puffer piston 4, the connecting rod 5, the puffer cylinder 6, and the partition 7 is a mechanical puffer chamber, and the internal space 60 defined by the movable contact 2, the open / close rod 5, and the internal cylinder 10 is arc-extinguishing. An internal space 70 defined by the flow path of the reactive gas, the puffer cylinder 6, the partition 7 and the inner cylinder 10 is a thermal puffer chamber, and 100 is an arc generated between the fixed contact 1 and the movable contact 2.

The piston rod 3 is moved in the left and right direction in the figure by the driving device with the opening and closing operation. The puffer cylinder 6 is fixed to the piston rod 3 via the partition wall 7, the inner cylinder 10, and the movable contact 2, and moves as the piston rod 3 moves in the left-right direction. On the other hand, the puffer piston 4 and the open / close bar 5 fixed thereto are stationary. Therefore, the arc-extinguishing gas in the mechanical puffer chamber 50 is compressed during the opening operation. The arc-extinguishing gas in the compressed mechanical puffer chamber 50 is controlled by the valve 11 and moves into the thermal puffer chamber 60 through the communication hole 8. FIG. 2 is a cross-sectional view showing an example of the valve 11. The valve 11 includes a spring 11 a and a latch 11 b. The latch 11 b is movable along a guide 6 a provided on the puffer cylinder 6.

Next, the opening operation will be described. FIG. 3 is a time chart showing a current waveform at the time of opening, where T1 and T2 indicate two opening times and T3 indicates a cutoff time. First, a case will be described in which the stationary contact 1 and the movable contact 2 are opened at time T1 and the interruption of the large current is completed at time T3 after a relatively long arc time. In the state of FIG. 1A, the arc-extinguishing gas pressure in the mechanical puffer chamber 50 and the heat puffer chamber 60 is the same as that in the casing. With the opening operation, the puffer piston 6 moves to the left and compresses the arc-extinguishing gas in the mechanical puffer chamber 50. At this point, valve 11
Is closed and the inside of the mechanical puffer chamber 50 and the thermal puffer chamber 60
The arc-extinguishing gas inside does not move.

Next, the fixed contact 1 and the movable contact 6 are opened, and until the throat portion of the nozzle 9 covers the tip of the fixed contact 1 as shown in FIG. In the meantime,
The arc-extinguishing gas heated by the arc 100 and having an increased pressure flows into the thermal puffer chamber 70, and the arc-extinguishing gas pressure in the thermal puffer chamber 70 increases. This arc-extinguishing gas flow is rapid and the arc-extinguishing gas pressure in the thermal puffer chamber 70 is higher than that in the mechanical puffer chamber 50 and reaches a saturation pressure determined by the energy of the arc 100. This saturation pressure is
When the pressure is high enough to open 1 but the arc-extinguishing gas pressure is higher than the arc-extinguishing gas pressure in the machine puffer chamber 50, the valve 11 is kept closed by the latch 11b.
When the arc-extinguishing gas pressure in the mechanical puffer chamber 50 further rises and exceeds the arc-extinguishing gas pressure in the thermal puffer chamber 70, the latch 11b is released, and the valve 11 is turned on by the arc-extinguishing gas pressure in the thermal puffer chamber 70. The valve 11 is pushed out of the puffer cylinder 6, the valve 11 is opened, and the arc-extinguishing gas in the mechanical puffer chamber 50 flows into the thermal puffer chamber 70.

When the piston rod 3 moves further, FIG.
When the state shown in (C) is reached, the tip of the fixed contact 1 comes off the throat portion of the nozzle 9 and the position of the partition 7 reaches the small-diameter portion of the opening / closing rod 5. Part of the gap between the partition 7 and the opening and closing rod 5 and the flow path 60
, The current is cut off at time T3 and the state shown in FIG. 1D is reached, and the cutoff operation is completed. The valve 11 closes due to the arc-extinguishing gas pressure drop in the thermal puffer chamber 70.

Next, the fixed contact 1 and the movable contact 2 are set at time T.
The case where the current interruption is completed at time T3 after a short arc time after opening the electrode at 2 will be described. In this case, arc 1
00 is short, the pressure of the arc-extinguishing gas in the heat puffer chamber 70 is low, and the valve 11 is not opened. In this case, the arc-extinguishing gas does not flow from the mechanical puffer chamber 50 into the thermal puffer chamber 70, but the tip of the fixed contact 1 comes off the throat portion of the nozzle 9 and the position of the partition 7 is changed to the open / close rod. 5
And the arc-extinguishing gas in the mechanical puffer chamber 50 is blown directly to the arc 100 through the gap between the partition wall 7 and the opening and closing rod 5 and the flow path 60, and the current is interrupted at time T3. The state shown in FIG. 1 (D) is reached and the cutoff operation is completed. In addition, even if the duration of the arc 100 is long, the breaking current is small and the arc-extinguishing gas pressure in the heat
The same applies to the case where the pressure at which 1 can be released is not reached.

As described above, the flow of the arc-extinguishing gas from the inside of the mechanical puffer chamber 50 to the inside of the thermal puffer chamber 70 is controlled by the arc-extinguishing gas pressure in the thermal puffer chamber 70. The arc gas can be efficiently blown to the arc 100, and the current can be reliably interrupted regardless of the magnitude of the interrupting current or the opening timing. In addition, valve 1
1 has been described with reference to the configuration of FIG.
Any other type of check valve that allows the flow of the arc-extinguishing gas from the mechanical puffer chamber 50 into the thermal puffer chamber 70 only when the pressure of the arc-extinguishing gas inside the chamber has reached a predetermined level. It may be something.

Embodiment 2 FIG. FIG. 4 is a cross-sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a second embodiment of the present invention, and four figures shown in (A), (B), (C) and (D) are As in the case of FIG. 1, the same or corresponding parts as those of the puffer type circuit breaker shown in FIG. 1 are represented by the same reference numerals, and only the parts different from FIG. 1 will be described.

The difference from the puffer type circuit breaker shown in FIG. 1 is as follows. The movable contact 2 penetrates the center of the partition 7 and is fixed to the puffer cylinder 6 without the opening and closing rod 5. The inner cylinder 10 is fixed to the partition 7 and the movable contact 2 is spaced apart from the puffer cylinder 6 by a relatively small gap.
And is opened near the end of the movable contact 2 on the fixed contact 1 side. The mechanical puffer chamber 50 is an internal space defined by the movable contact 2, the puffer piston 4, the puffer cylinder 6, and the partition 7. The flow path 60 is an internal space defined by the puffer cylinder 6, the partition 7, and the internal cylinder 10. The thermal puffer chamber 70 is an internal space defined by the movable contact 2, the partition 7, and the internal cylinder 10. The partition wall 7 is provided with a first communication hole 8a in a portion that partitions the mechanical puffer chamber 50 and the heat puffer chamber 70, and a second communication hole 8b in a portion that partitions the mechanical puffer chamber 50 and the flow path 60. A check valve 11a for opening and closing the first communication hole 8a and a flow passage valve 11b for opening and closing the second communication hole 8b, and a valve opening and closing control device 11c for controlling the opening and closing operations of both the check valve 11a and the flow passage valve 11b It is provided with.

The check valve 11a controls the flow of the arc-extinguishing gas from the interior of the thermal puffer chamber 70 into the mechanical puffer chamber 50,
1b blocks the flow from the flow path 60 into the mechanical puffer chamber 50, respectively. The valve opening / closing control device 11c includes a check valve 11a.
Alternatively, when one of the flow path valves 11b is open, a mechanism is provided for preventing the other from opening. FIG. 5 is a cross-sectional view showing an example of the valve opening / closing control device 11c.
The open / close control hook 11ca provided with a1 and the spring 11cb are movable along a guide 6b provided on the puffer cylinder 6. When the internal pressure of the heat puffer chamber 70 is low, the latch 11ca1
Prevents the check valve 11a from opening, and in a high state, the opening / closing control hook 11ca pushes up the spring 11cb to raise the latch 11ca1.
Prevents opening of the flow path valve 11b.

Next, the opening operation will be described. When the arc time is relatively long due to the interruption of the large current, the pressure of the arc-extinguishing gas in the heat puffer chamber 70 is high and the opening / closing control hook 11ca is kept pushed up from the beginning of the interruption to the end of the interruption, so that the flow path valve 11b is closed. Stay in the machine puffer room 50
The arc-extinguishing gas inside flows into the thermal puffer chamber 70 via the check valve 11a, and is blown to the arc 100 together with the arc-extinguishing gas in the thermal puffer chamber 70. In the case where the arc time is short due to interruption of a large current or in the case of interruption of a small current, the opening / closing control hook 11ca prevents the check valve 11a from opening, so that the arc-extinguishing gas in the machine puffer chamber 50 passes through the flow path valve 11b. It is sprayed on the arc 100 via.

As described above, the flow of the arc-extinguishing gas from the inside of the mechanical puffer chamber 50 to the inside of the thermal puffer chamber 14 is controlled by the arc-extinguishing gas pressure in the thermal puffer chamber 70 to extinguish the arc in the mechanical puffer chamber 50. The active gas can be efficiently blown to the arc 100, and the current can be reliably interrupted regardless of the magnitude of the interrupting current or the opening timing. The valve opening / closing control device 11c has been described with reference to FIG.
Other types may be used as long as they can control the opening and closing of the valve a and the flow path valve 11b as described above.

Embodiment 3 FIG. FIG. 6 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a third embodiment of the present invention, which has the same drawing configuration as that of FIG. It differs from the puffer circuit breaker shown in FIG. 1 in the following points. The movable contact 2, the puffer cylinder 6, and the partition 7 are fixed to each other without the opening and closing bar 5. The inner cylinder 10 is formed so as to surround the movable contact 2 with a relatively narrow gap between the inner cylinder 10 and the puffer cylinder 6 and is fixed to the partition wall 7. The mechanical puffer chamber 50 is an internal space defined by the movable contact 2, the puffer piston 4, the puffer cylinder 6 and the partition 7, and the flow channel 60 is a puffer cylinder 6 and the partition 7.
The heat puffer chamber 70 is an internal space defined by the movable contact 2, the partition 7, and the internal cylinder 10. The partition wall between the mechanical puffer chamber 50 and the flow path 60 is provided with a ventilation hole through which the arc-extinguishing gas flows without resistance. The end of the heat puffer chamber 70 on the fixed contact 1 side is closed by an end plate 10a, and a communication hole 8c is provided in the end plate 10a. A valve 11d is provided at a portion of the puffer cylinder 6 opposite to the communication hole 8a for controlling the opening and closing of the communication hole 8c by the arc-extinguishing gas pressure near the arc 100 when current is interrupted. An arc-extinguishing gas is applied to the fixed contact 1 end of the flow path 60 on the fixed contact 1 side.
A check valve 11e is provided to prevent flow from the side into the machine puffer chamber 50 through the flow path 60.

Next, the opening operation will be described. When the arc time is relatively long due to interruption of a large current, the valve 11d is opened by the arc-extinguishing gas pressure near the arc 100 at the initial stage of interruption, and the arc-extinguishing gas near this arc flows into the heat puffer chamber 70. When the arc-extinguishing gas pressure in the machine puffer chamber 50 exceeds the arc-extinguishing gas pressure near the arc 100 with the movement of the puffer cylinder 6, the check valve 11e opens and the arc-extinguishing property in the machine puffer chamber 50 continues until the end of shutoff. The gas is in the heat puffer chamber 70
The arc 100 is blown with the arc-extinguishing gas flowing into the inside. In the case where the arc time is short due to interruption of a large current or in the case of interruption of a small current, the arc-extinguishing gas in the machine puffer chamber 50 passes through the check valve 11e without opening the valve 11d.
0 is sprayed.

As described above, the flow of the arc-extinguishing gas into the heat puffer chamber 70 is controlled by the valve 11d,
The arc-extinguishing gas into the mechanical puffer chamber 50 and the thermal puffer chamber 70 or the arc-extinguishing gas in the mechanical puffer chamber 50 can be efficiently blown to the arc 100 according to the nearby arc-extinguishing gas pressure, The current can be reliably interrupted regardless of the magnitude of the interrupting current and the opening timing.

Embodiment 4 FIG. 7 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a fourth embodiment of the present invention, which has the same drawing configuration as that of FIG. It differs from the puffer circuit breaker shown in FIG. 1 in the following points. The inside of the puffer cylinder 6 is divided into two parts by a partition wall 7. The inner cylinder 10 is fixed to the partition 7 so as to wrap the movable contact 2 with a relatively small gap between the inner cylinder 10 and the puffer cylinder 6, and the end thereof extends to near the center of the fixed contact 1 side space. The movable contact 2 is closed by the end plate 10b. An annular piston 7a is mounted between the puffer cylinder 6 and the inner cylinder 10 with a partition 7 via a spring 7b. The mechanical puffer chamber 50 is an internal space defined by the movable contact 2, the puffer piston 4, the puffer cylinder 6, and the partition 7, and the flow path 60 is defined by the movable contact 2, the partition 7, the internal cylinder 10, and the end plate 10b. The internal space, that is, the heat puffer chamber 70 is an internal space defined by the movable contact 2, the free piston 7a, and the internal cylinder 10. The partition wall 7 between the mechanical puffer chamber 50 and the flow path 60 is provided with a ventilation hole through which the arc-extinguishing gas flows without resistance. The end plate 10b is provided with a communication hole 10c, and a check valve 11f for preventing the arc-extinguishing gas from flowing into the flow path 60 from the inside of the heat puffer chamber 70.

Next, the opening operation will be described. When the arc time is relatively long due to interruption of a large current, the arc-extinguishing gas heated by the arc 100 and having an increased pressure flows into the heat puffer chamber 70, so that the spring 7b is compressed and the piston 7a moves to the partition wall 7 side. The volume of the heat puffer chamber 70 is increased, and the arc-extinguishing gas having a high pressure is accumulated. Machine puffer room 5
When the arc-extinguishing gas pressure in the chamber 0 exceeds the arc-extinguishing gas pressure in the thermal puffer chamber 70, the check valve 11f opens and the mechanical puffer chamber 5 is opened.
The arc-extinguishing gas in the gas flows into the heat puffer chamber 70 and the spring 7
While being pushed by the pushing force of the piston 7a by b, it is blown to the arc 100 together with the arc-extinguishing gas in the heat puffer chamber 70. When the arc time is short due to the interruption of the large current or the interruption of the small current, there is no accumulation of the arc-extinguishing gas due to the movement of the piston 7a, but the arc-extinguishing gas pressure in the mechanical puffer chamber 50 increases in the thermal puffer chamber 70. Is exceeded, the arc-extinguishing gas in the machine puffer chamber 50 is blown to the arc 100 through the check valve 11f.

As described above, when the arc-extinguishing gas pressure in the vicinity of the arc 100 is high, more arc-extinguishing gas is accumulated in the thermal puffer chamber 70 together with the gas arc-extinguishing gas in the mechanical puffer chamber 50. When the arc-extinguishing gas pressure in the vicinity of the arc 100 is low, the gas-extinguishing gas in the mechanical puffer chamber 50 can be efficiently blown to the arc 100, regardless of the magnitude of the breaking current or the opening timing. The current can be reliably shut off. The check valve 11f is connected to the flow path 6
However, the arc-extinguishing gas pressure in the mechanical puffer chamber 50 is set at the heat puffer chamber 7 side.
When the arc-extinguishing gas pressure within 0 is exceeded, the check valve 11f is opened and the arc-extinguishing gas in the mechanical puffer chamber 50 is released from the heat puffer chamber 70.
What is necessary is just to provide so that it may flow into the inside, and it may be provided somewhere in the flow path 60.

[0028]

The puffer type gas circuit breaker according to the present invention divides the inside of the puffer cylinder into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contact side, and communicates with the mechanical puffer chamber around the movable contact. An arc extinguishing gas from the mechanical puffer chamber to the thermal puffer chamber when the arc extinguishing gas in the mechanical puffer chamber and the thermal puffer chamber reach a predetermined pressure, respectively. A non-return valve that permits the movement of the fixed pouch and a flow path valve that opens when the fixed contact and the movable contact are separated by a predetermined distance or more between the flow path and the mechanical puffer chamber. The arc-extinguishing gas can be efficiently blown to the arc, and the current can be reliably interrupted regardless of the magnitude of the interrupting current or the opening timing.

The flow path valve has a movable contact penetrating through the central portion thereof, is fixed to the puffer piston, and has an opening / closing rod having a small diameter at the puffer piston side and a large diameter at the other end as a valve body, and a mechanical puffer chamber and a thermal puffer chamber. Since the inner diameter of the partition wall that separates the valve is used as a valve seat, the structure of this valve is simple, its operating position is accurate, and its operation is reliable.

The interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contactor side, and communicates with the mechanical puffer chamber between the puffer cylinder and an opening near the opening of the thermal puffer chamber. Flow path,
Between the mechanical puffer chamber and the flow path, the arc-extinguishing gas is moved only from the mechanical puffer chamber to the flow path. Between the mechanical puffer chamber and the thermal puffer chamber, only the heat is extinguished from the mechanical puffer chamber to the thermal puffer chamber. A check valve for moving the arc gas is provided, and a valve opening / closing control device for closing the check valve when the arc-extinguishing gas in the heat puffer chamber is at a predetermined pressure or higher and a check valve at a predetermined pressure or lower is provided. The arc-extinguishing gas in the mechanical puffer chamber can be efficiently blown to the arc, and the current can be reliably interrupted regardless of the magnitude of the interrupting current and the opening timing.

The interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contact side, and communicates with the mechanical puffer chamber between the puffer cylinder and an opening near the opening of the thermal puffer chamber. Flow path,
A flow valve that moves the arc-extinguishing gas from the inside of this flow path only to the arc generating section and a heat puffer chamber and an arc generating section when the arc generating section exceeds a predetermined arc-extinguishing gas pressure And a valve that allows the arc-extinguishing gas to move between the arc-extinguishing gas and the arc-extinguishing gas in the mechanical puffer chamber can be efficiently blown to the arc. The current can be reliably shut off.

The interior of the puffer cylinder is divided into a mechanical puffer chamber on the puffer piston side and a thermal puffer chamber on the fixed contactor side, and a flow that communicates with the mechanical puffer chamber between the movable contactor and opens inside the thermal puffer chamber. And a flow path valve that moves the arc-extinguishing gas only from the mechanical puffer chamber to the thermal puffer chamber in this flow path, and an arc-extinguishing of the thermal puffer chamber according to the increase and decrease of the arc-extinguishing gas pressure in the thermal puffer chamber. Equipped with a piston to increase or decrease the amount of oxidative gas, so that the arc-extinguishing gas in the machine puffer chamber can be efficiently blown to the arc,
The current can be reliably interrupted regardless of the magnitude of the interrupting current and the opening timing.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a structural example of a valve 11 of FIG.

FIG. 3 is a time chart showing a current waveform when the circuit breaker is opened.

FIG. 4 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a structural example of a valve opening / closing control device 11c in FIG.

FIG. 6 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a third embodiment of the present invention.

FIG. 7 is a sectional view showing an arc-extinguishing chamber portion of a puffer-type circuit breaker according to a fourth embodiment of the present invention.

[Explanation of symbols]

1 fixed contact, 2 movable contact, 3 piston rod 4 puffer piston, 5 open / close rod, 6 puffer cylinder, 7 bulkhead 8 communication hole, 9 nozzle, 10 internal cylinder, 11 mm Valve 50 ‥ mechanical puffer chamber, 60 ‥ flow path, 70 ‥ heat puffer chamber, 100 ‥ arc

Continued on the front page (72) Inventor Kentaro Ogura 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Mitsubishi Electric Corporation (reference) 5G001 AA01 BB03 CC03 DD03 EE12

Claims (5)

[Claims] 1. A casing filled with an arc-extinguishing gas, a fixed contact fixed in the casing, a movable contact connected to a driving device and opposed to the fixed contact so as to be separated from the movable contact. A contactor penetrates a central portion and is fixed to the casing, and a puffer cylinder connected to and surrounding the movable contact and fitted with the puffer piston so as to be slidable in the inner axial direction. Moving the movable contact by the driving device and injecting the arc-extinguishing gas compressed therein by the movement of the puffer cylinder to an arc generated when the fixed contact and the movable contact are separated. A puffer type gas circuit breaker, wherein a mechanical puffer chamber located inside the puffer cylinder in the axial direction on the puffer piston side and the fixed contactor side. And a flow path which is divided into two portions with a heat puffer chamber located therein, communicates with the mechanical puffer chamber around the movable contact and opens near the opening of the heat puffer chamber. When the quenching gas reaches a predetermined pressure and the arc-extinguishing gas in the mechanical puffer chamber exceeds a predetermined pressure, the quenching from the mechanical puffer chamber to the thermal puffer chamber occurs. A first valve that permits the movement of an arc gas, and a second valve that opens when the fixed contact and the movable contact are separated by a predetermined distance or more between the flow path and the mechanical puffer chamber. A puffer type gas circuit breaker comprising: 2. The valve according to claim 2, wherein the movable contact penetrates a center portion and is fixed to the puffer piston, and an opening / closing rod having a small diameter on the puffer piston side and a large diameter on the other end side is a valve body. The puffer type gas circuit breaker according to claim 1, wherein an inner diameter portion of a partition separating the mechanical puffer chamber and the thermal puffer chamber is used as a valve seat. 3. A casing filled with an arc-extinguishing gas, a fixed contact fixed in the casing, a movable contact connected to a driving device and arranged so as to be able to contact and separate from the fixed contact. A contactor penetrates a central portion and is fixed to the casing, and a puffer cylinder connected to and surrounding the movable contact and fitted with the puffer piston so as to be slidable in the inner axial direction. Moving the movable contact by the driving device and injecting the arc-extinguishing gas compressed therein by the movement of the puffer cylinder to an arc generated when the fixed contact and the movable contact are separated. A puffer type gas circuit breaker, wherein a mechanical puffer chamber located inside the puffer cylinder in the axial direction on the puffer piston side and the fixed contactor side. A flow path that is divided into a heat puffer chamber and a flow path that communicates with the mechanical puffer chamber between the puffer cylinder and the heat puffer chamber and that opens near the opening of the heat puffer chamber; A first valve permitting movement of the arc-extinguishing gas from the mechanical puffer chamber into the flow path between the mechanical puffer chamber and the thermal puffer chamber; And a second valve allowing the movement of the arc-extinguishing gas is provided,
A puffer-type gas shut-off device comprising a valve opening / closing control device that closes the first valve when the arc-extinguishing gas in the thermal puffer chamber is at a predetermined pressure or higher and closes the second valve when the arc-extinguishing gas is at or below a predetermined pressure. vessel. 4. A casing filled with an arc-extinguishing gas, a fixed contact fixed in the casing, a movable contact connected to a driving device and opposed to the fixed contact so as to be able to contact and separate from the fixed contact. A contactor penetrates a central portion and is fixed to the casing, and a puffer cylinder connected to and surrounding the movable contact and fitted with the puffer piston so as to be slidable in the inner axial direction. Moving the movable contact by the driving device and injecting the arc-extinguishing gas compressed therein by the movement of the puffer cylinder to an arc generated when the fixed contact and the movable contact are separated. A puffer type gas circuit breaker, wherein a mechanical puffer chamber located inside the puffer cylinder in the axial direction on the puffer piston side and the fixed contactor side. A flow path that divides into two parts into a heat puffer chamber and communicates with the mechanical puffer chamber between the puffer cylinder and the heat puffer chamber and opens near the opening of the heat puffer chamber; A first valve permitting movement of the arc-extinguishing gas from the arc to the arc-generating unit, and the heat puffer chamber and the arc-generating unit when the arc-generating unit exceeds a predetermined arc-extinguishing gas pressure. And a second valve that allows the movement of the arc-extinguishing gas between the puffer-type gas circuit breaker. 5. A casing filled with an arc-extinguishing gas, a fixed contact fixed in the casing, a movable contact connected to a driving device and arranged so as to be able to contact and separate from the fixed contact. A contactor penetrates a central portion and is fixed to the casing, and a puffer cylinder connected to and surrounding the movable contact and fitted with the puffer piston so as to be slidable in the inner axial direction. Moving the movable contact by the driving device and injecting the arc-extinguishing gas compressed therein by the movement of the puffer cylinder to an arc generated when the fixed contact and the movable contact are separated. A puffer type gas circuit breaker, wherein a mechanical puffer chamber located inside the puffer cylinder in the axial direction on the puffer piston side and the fixed contactor side. And a flow path that communicates with the mechanical puffer chamber between the movable contactor and opens in the heat puffer chamber, and a flow path that is open from the mechanical puffer chamber into the flow path. A flow path valve that allows the movement of the arc-extinguishing gas into the heat puffer chamber and moves through the heat puffer chamber to increase or decrease the arc-extinguishing gas capacity of the heat puffer chamber according to an increase or decrease in the arc-extinguishing gas pressure. A puffer type gas circuit breaker comprising a piston for increasing and decreasing.