Arc gas venting structure of air circuit breaker

Abstract

One or more arc gas outlet holes are formed in a trip device such that an effect of easily venting an arc gas, which flows into the trip device, to the outside through the arc gas outlet holes is provided.

Claims

1. An arc gas venting structure of an air circuit breaker, which comprises a body having an accommodation space therein, an over current relay provided in front of the body, a trip device connected to the over current relay and configured to operate a switching mechanism, and the switching mechanism driven by the trip device to adjust contact or separation between a movable contact and a fixed contact, wherein the trip device comprises: a frame which forms an exterior; one or more arc gas inlet holes formed at the frame to allow an arc gas to flow into the trip device; and one or more arc gas outlet holes formed at the frame to vent the arc gas which has flowed into the trip device.

2. The arc gas venting structure of claim 1, wherein an incline is formed below the body to be adjacent to the one or more arc gas outlet holes.

3. The arc gas venting structure of claim 2, wherein the one or more arc gas outlet holes are formed to have a lateral length longer than a longitudinal length.

4. The arc gas venting structure of claim 3, wherein a bottom surface of the one or more arc gas outlet holes is formed to incline toward the incline.

5. The arc gas venting structure of claim 2, wherein the body comprises a front frame which is located to be adjacent to the trip device and has a bottom at which the incline is formed such that a flow space of the arc gas vented through the one or more arc gas outlet holes is provided through the incline.

6. The arc gas venting structure of claim 5, wherein the incline is located below the one or more arc gas outlet holes.

7. The arc gas venting structure of claim 1, further comprising a breaking plate, which allows the arc gas which has flowed into the trip device to move toward the one or more arc gas outlet holes on an inner side of the trip device toward the over current relay.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing exemplary embodiments thereof in detail with reference to the accompanying drawings, in which:

(2) FIG. 1 is a perspective view of a conventional air circuit breaker;

(3) FIG. 2 is a front view illustrating a relay provided at the conventional air circuit breaker and a trip device connected thereto;

(4) FIG. 3 is a perspective view illustrating the relay provided at the conventional air circuit breaker and the trip device connected thereto;

(5) FIG. 4 is a front view of an air circuit breaker according to one embodiment of the present invention;

(6) FIG. 5 is a side perspective view of the air circuit breaker according to one embodiment of the present invention;

(7) FIG. 6 is a front view illustrating a frame of a trip device provided at the air circuit breaker according to one embodiment of the present invention;

(8) FIG. 7 is a front view illustrating a state in which an incline is formed on a front frame provided at the air circuit breaker according to one embodiment of the present invention; and

(9) FIG. 8 is a perspective view illustrating the state in which the incline is formed on the front frame provided at the air circuit breaker according to one embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(10) Hereinafter, an arc gas venting structure of an air circuit breaker according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

(11) FIG. 4 is a front view of the air circuit breaker according to an embodiment of the present invention, FIG. 5 is a side perspective view of the air circuit breaker according to one embodiment of the present invention, FIG. 6 is a front view illustrating a frame of a trip device provided at the air circuit breaker according to one embodiment of the present invention, FIG. 7 is a front view illustrating a state in which an incline is formed on a front frame provided at the air circuit breaker according to one embodiment of the present invention, and FIG. 8 is a perspective view illustrating the state in which the incline is formed on the front frame provided at the air circuit breaker according to one embodiment of the present invention.

(12) As shown in FIGS. 4 and 5, an air circuit breaker 100 according to one embodiment of the present invention includes a body 101, an over current relay 110 located in front of the body 101, a trip device 150 located in the body 101 and connected to the over current relay 110, and a switching mechanism 130 which is driven through the trip device 150 and brings a movable contact and a fixed contact into contact with each other or separates them from each other.

(13) The body 101 provides an accommodation space to accommodate components therein and accommodates the trip device 150, the switching mechanism 130, an arc quenching portion (not shown), and the like therein.

(14) The over current relay 110 detects an inflow of current having a level higher than a preset current value, thereby detecting a fault current or an over current, and prevents the current from flowing into the air circuit breaker 100 by driving the switching mechanism 130.

(15) The trip device 150 is disposed between the over current relay 110 and the switching mechanism 130 and generates and transmits a mechanical operating force to the switching mechanism 130 when a trip command of the over current relay 110 is output.

(16) Here, as shown in FIG. 6, a frame 151 which forms an exterior of the trip device 150 includes a plurality of arc gas inlet holes 151a. The arc gas inlet holes 151a are configured to rotate a main shaft 131 formed in the switching mechanism 130.

(17) Also, one or more arc gas outlet holes 151b are formed below the arc gas inlet holes 151a to vent an arc gas, which flows into the trip device 150 through the arc gas inlet holes 151a, to the outside. That is, the arc gas inlet holes 151a and the arc gas outlet holes 151b are formed in the same frame 151.

(18) In a conventional case, an arc gas, which is generated when the movable contact and the fixed contact are separated, flows into the trip device 150 through the arc gas inlet holes 151a and applies a pressure to the trip device 150. The pressure influences an operating property of the trip device 150 as well as the over current relay 110 such that the over current relay 110 may malfunction.

(19) However, according to the one embodiment of the present invention, one or more arc gas outlet holes 151b are formed below the arc gas inlet holes 151a. Accordingly, the arc gas, which pressurizes the trip device 150 through the arc gas inlet holes 151a, is vented outward from the trip device 150 through the arc gas outlet holes 151b. Accordingly, an influence of the arc gas on the trip device 150 is minimized.

(20) Here, the arc gas outlet hole 151b may have a lateral length longer than a longitudinal length. A large amount of arc gas may be vented outward from the trip device 150 through the arc gas outlet holes 151b.

(21) Additionally, as shown in FIGS. 7 and 8, the body 101 includes a front frame 105 located to be adjacent to the trip device 150.

(22) The front frame 105 is located to face the trip device 150 and prevents the arc gas, which is generated when the movable contact and the fixed contact are separated, from flowing into the trip device 150. However, since arc leakage holes 105a are formed at the front frame 105 to rotate the main shaft 131 provided at the switching mechanism 130, the arc gas moves toward the trip device 150 through the arc leakage holes 105a.

(23) Accordingly, the arc gas, which has moved toward the trip device 150 through the arc leakage holes 105a, flows into the trip device 150 through the arc gas inlet holes 151a and then is vented outward from the trip device 150 through the arc gas outlet holes 151b.

(24) Meanwhile, an incline 105b is formed at the front frame 105 provided at the body 101 to be adjacent to the arc gas outlet holes 151b. That is, the incline 105b is formed on another frame (the front frame) not the frame 151 in which the arc gas inlet holes 151a and the arc gas outlet holes 151b are formed.

(25) An adequate flow space through which the arc gas may move is formed below the front frame 105 through the incline 105b. Accordingly, the arc gas vented through the arc gas outlet holes 151b may adequately move in the front frame 105 to reduce the pressure thereof and be vented to the outside.

(26) In addition, a bottom surface of the arc gas outlet hole 151b may be formed to incline, and the incline 105b may be formed to be located below the arc gas outlet holes 151b.

(27) Accordingly, the bottom surface of the arc gas outlet hole 151b is formed to incline and the incline 105b is located below the arc gas outlet hole 151b such that the arc gas which has flowed into the trip device 150 is quickly vented toward the incline 105b.

(28) Hereinafter, a process in which an arc gas is vented to the outside through the arc gas venting structure of the air circuit breaker 100 according to one embodiment of the present invention will be described in detail.

(29) First, when the over current relay 110 detects an inflow of a fault current and operates the trip device 150, the switching mechanism 130 is operated by the trip device 150 to separate the movable contact and the fixed contact from each other such that the air circuit breaker 100 changes to a trip (OFF) state.

(30) Here, when the fixed contact and the movable contact are separated, an arc gas A is generated. Here, the arc gas A is vented to the outside through the arc quenching portion and simultaneously moves toward the trip device 150 through the arc leakage holes 105a formed at the front frame 105.

(31) The arc gas which has moved toward the trip device 150 flows into the trip device 150 through the arc gas inlet holes 151a formed at the trip device 150. The arc gas which flows into the trip device 150 is vented outward from the trip device 150 again through the arc gas outlet holes 151b.

(32) Here, the pressure of the arc gas is not applied to the over current relay 110 connected to the trip device 150 due to a breaking plate 170 provided in the trip device 150.

(33) Also, the arc gas vented outward from the trip device 150 through the arc gas outlet holes 151b freely moves through the space formed below the front frame 105 to reduce the pressure thereof through the incline 105b and is vented to the outside.

(34) According to one embodiment of the present invention, the one or more arc gas outlet holes 151b are formed at the trip device 150 such that an arc gas which flows into the trip device 150 is easily vented to the outside through the arc gas outlet holes 151b. Accordingly, an influence applied to the trip device 150 or the over current relay 110 by the arc gas is minimized.

(35) Also, since the arc gas outlet holes 151b have the lateral length longer than the longitudinal length, a large amount of arc gas is vented outward from the trip device 150 through the arc gas outlet holes 151b in a short time.

(36) Also, the bottom surface of the arc gas outlet hole 151b is formed to incline, and the incline 105b formed on the front frame 105 is located below the arc gas outlet holes 151b. Accordingly, the arc gas vented through the arc gas outlet holes 151b is allowed to quickly move toward the incline 105b.

(37) Also, since an adequate space through which the arc may move is secured through the incline 105b formed at the front frame 105, the arc gas freely moves in the front frame 105 such that a pressure of the arc gas is reduced.

(38) According to the embodiments of the present invention, an arc gas venting structure of an air circuit breaker provides an effect of freely venting an air gas which flows into a trip device to the outside through at least one arc gas outlet hole formed at the trip device.

(39) Also, the arc gas vent hole is formed to have a lateral length longer than a longitudinal length such that an effect of venting a large amount of arc gas through the arc gas vent hole in a short time may be provided.

(40) Also, a bottom surface of the arc gas vent hole is formed to incline and an incline formed at a front frame is located below the arc gas outlet hole such that an effect of quickly moving the arc gas vented through the arc gas vent hole toward the incline to be vented outside may be provided.

(41) Also, an adequate space for allowing the arc gas to flow is secured through the incline formed at the front frame such that an effect in which the arc gas freely flows in the front frame to reduce a pressure thereof may be provided.

(42) Although an exemplary embodiment of the present invention has been described above, it is clear that the present invention may include a variety of changes, modifications, and equivalents thereof and the embodiment may be adequately modified to be equivalently applied. Accordingly, the scope of the present invention defined by the limitation of the following claims is not limited to the above description.