JPS5873931A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] This invention increases arc resistance by bringing the arc absorber closer to the fixed and movable contacts and quickly absorbing the arc energy when a large short-circuit current flows in the circuit. , relates to improvements in circuit breakers that quickly interrupt short-circuit currents.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a molded case, 2 is a fixed contact conductive plate, and a fixed contact 3 is fixed to one end thereof. Reference numeral 4 designates a movable contact conductive plate having a substantially U-shape, the bottom of which is mounted so as to be pivotable about a square protrusion 51 of a connecting conductor 5, which will be described later. , 6 is a movable contact fixed to the tip of the movable contact conductive plate 4, and is disposed opposite to the fixed contact 3. Reference numeral 7 denotes an insulating case 8, which will be described later.W is a rotatable head on a pivot shaft 9 fixed to W; it is an arc absorber having a fire heat capacity and having a substantially rectangular shape, and rotates close to the fixed and movable contacts 3 and 6. At the same time, recesses 7m and 7b for receiving a separation spring (first elastic body) 10 and a compression coil spring (second elastic body) 11, which will be described later, are provided. Reference numeral 1o denotes a release spring (first elastic body) that is held between a part 1& of the molded case 1 and a recess 7& of the arc absorber 7, and the arc absorber 7 is shown by the arrow (A). It is biased counterclockwise. Reference numeral 11 denotes a compression coil spring (second elastic body) that is elastically attached between the recess 7b of the arc absorber 7 and the movable contact conductive plate 4, and the elastic force in the axial direction is applied to the movable contact conductive plate 4. The bottom portion 4 of the plate 4 and the connecting conductor (to be described later) (shaped protrusion 51) act on the movable contact 6 and the fixed contact 3, and the elastic force in the curved direction acts on the movable contact 6 and the fixed contact 3. Therefore, the current is Flow occurs in the order of fixed contact conductive plate 2 → fixed contact 3 → movable contact 6 → movable contact conductive plate 4 → contact conductor 5. The above 5 is a connecting conductor fixed to an insulating case 8, which will be described later, and one end is connected to the above-mentioned. A wedge-shaped protrusion 5
1L and serves as a connection point for the movable contact conductive plate 4,
The other end is connected to a trip element (not shown) of an automatic 4-release device. 8 is an arc absorber 7, a compression coil spring 11,
Movable contact conductive plate 4, fixed contact conductive plate 2, connection conductor 5
, an insulating case that houses the fixed contact 3 and the movable contact 6, in which arc gas generated between the fixed and movable contacts 3 and 6 is discharged to the opening/closing mechanism and the automatic 4 release device (not shown). to prevent Reference numeral 12 denotes a manual handle rotatably attached to a pivot shaft 15 provided on a fixed frame (not shown), and is in the ON state in FIG. 1. Reference numeral 14 denotes a link A rotatably supported by a pin 15 at the tip of the manual handle 12, and a roller 8 is provided at the free end of the link A, which contacts the upper end of a link B 16, which will be described later, and the back surface of a lever 17. ing. 17 is a fixed frame (
The lever is rotatably attached to a pivot shaft 19 (not shown), and engages with a tripping lever 20, which will be described later, to restrict its rotation. 20] is a trip lever 111M8 that is rotatable around a pivot 21Y provided on a fixed frame (not shown), and when a short circuit current 1 flows into the circuit, an automatic 4 release element (not shown)
By detecting □, it rotates in the 4=clockwise direction as shown by the arrow (b). Reference numeral 16 denotes a link B that is slidably mounted in the vertical direction between the back surface of the lever 17 and the first part 1b of the molded case 1, and the upper end inclined surface 16& of the lever in one direction comes into contact with the roller 18. The lower end contacts a link C22, which will be described later, and functions to transmit the displacement of the link A14 to the link C22, which will be described later. 22 is a link C rotatably attached to a pivot 26 provided on a fixed frame (not shown), and is connected to a part 1o of the mold case 1.
The link B16 is pressed upward by the elastic force of the link spring 24 made of a compression coil spring that is landed between the recess 221 and the arc absorber 7.
The counterclockwise rotation of the arc absorber 7 is restricted. In this way, link A14, link B16, link C22, tripping lever 21. The lever 17 constitutes an opening/closing mechanism.

Next, the operation of this invention will be explained.

As shown in FIG. 1, when the manual handle 12 is in the ON state,
If a short circuit current flows into the circuit, the automatic 4-release element (
(not shown) detects this and moves the tripping lever 20 with the arrow -
1, rotate the release lever 20 clockwise.
When the lever 17 is disengaged from the lever 17, the lever 17 is rotated clockwise as shown by the arrow (C) by the pressure of the roller 18.

As a result, the roller 18 is moved to the link B as shown in FIG.
It rotates in the direction of the lever 17 along the inclined surface 16 of the lever 16, falls into the gap X between the back surface of the lever 17 and the link B16, and releases the upper end of the link B16 from being suppressed.

Therefore, the link 022, which was in contact with the link B16 and whose rotation was restricted, rotates counterclockwise (as indicated by the arrow) by the elastic force of the link spring 24 so as to slide the link B16 upward. do.

At the same time, the tip 221 of the link C22 moves the contact position of the arc absorber 7 and releases the rotation of the arc absorber 7, so that the arc absorber 7 is ), it rotates counterclockwise around the pivot 9. Due to the force in the bending direction of the compression coil spring 11, which is not caused by the rotation of the arc absorber 7, the movable contact conductive plate 4 is As a result, the movable contact 6 fixed to the tip of the movable contact conductive plate 4 separates from the fixed contact 3, and an arc is generated between the two contacts 3 and 6.

However, due to the rotation of the arc absorber 7, its lower surface 7
As shown in FIG. 2, C approaches the fixed and movable contacts 3 and 6, and the generated arc is cooled by the arc absorber 7, so the arc resistance increases and the arc is quickly interrupted.

Furthermore, since the generated arc gas is discharged from the gaps Y and Z between the upper and lower ends of the arc absorber 7 and the insulating case 8, the discharge of arc gas to the outside of the mold case 1 is small, and the panel space can be reduced. becomes.

Next, in the trip state shown in Fig. 2, 1 manual handle 12
When rotated clockwise, the roller 18 closes the gap X between the back of the lever 17 and the link B16, contrary to the above-mentioned operation.
When the manual handle □12 slides upward and reaches the OFF position as shown in FIG. 3, the roller 18, the tripping lever 20, and the lever 17 are brought into engagement.

As described above, according to the present invention, the fixed and movable contacts are arranged close to the rotation path I of the arc absorber, so by rotating the arc absorber at the time of interruption, the arc absorber absorbs arc energy. However, it can increase arc resistance and quickly cut off short-circuit current.

[Brief explanation of the drawing]

Fig. 1 is a partially longitudinal front view of a circuit breaker according to an embodiment of the present invention in the ON state, Fig. 2 is a partially longitudinal front view of the circuit breaker in the tripped state, and Fig. 3 is a partially longitudinal front view of the circuit breaker in the OFF state. Show the diagram. 1... Malt case, 2... Fixed contact conductive plate, 3
... Fixed contact, 5... Connection conductor, 6... Movable contact, 7... Arc absorber, 9... Pivot, 10...
・First elastic body (separation spring), 11... Second elastic body (compression coil spring), 12... Manual handle, 14.
...Link person 1111 16...Link B, jl, 22-...Link C0
Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Shin Kuzuno (1 other person)

Claims (1)

[Claims] Tripping operation even when the manual position is 1kON and the position is locked.
The opening/closing mechanism has a trip-free mechanism that does not disturb the movement of the arc absorber and operates the link C for restricting rotation of the arc absorber at the time of disconnection by the switching operation of the manual handle. an arc absorber that is brought into contact with the link C of the opening/closing mechanism by rotational bias of the body, and the above-mentioned
A movable contact conductive plate is arranged close to the rotation path of the absorber, and is rotatably supported around a connecting conductor as a fulcrum, and the movable contact conductive plate and the arc absorber are connected to each other. a second elastic body that opens and closes the movable contact conductive plate by the rotation of the arc absorber; and a second elastic body that faces the movable contact and connects the arc absorber A fixed contact conductor plate and a fixed contact conductor plate arranged close together
i-circuit breaker.