JPS5849561Y2 - Small circuit breaker - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a small-sized circuit breaker, and its purpose is to provide a small-sized circuit breaker that has a simple structure, is particularly easy to assemble, and has a low floor.

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

In Figure 1, 1 is an insulating mold base, 2 is a power terminal, and 3 is a load terminal, one end of which is connected to an external load side lead (not shown) with a screw, and the other end is fixed to one end of a linear bimetal 4 by spot welding. be done.

Further, reference numeral 5 denotes a movable piece that rotates around the left end so that the movable contact 6 at the right end can be freely opened and closed with respect to the fixed contact 7 provided at one end of the power supply terminal 2.

Further, 8 is a U-shaped magnetic core fixed to the mold base 1, and a lead wire 9 wound several times around this is connected between one end of each of the bimetal 4 and the movable piece 5. When a large current flows through the lead wire 9, the lead wire 9 will be attracted.

11 is a coil winding that biases the instantaneous iron piece 10 in the counterclockwise direction in FIG. section 13, via a U link 15,
It is connected to a plate pressure spring 14, and the other end of the plate pressure spring 14 is hooked onto a claw portion 17 formed by a stepped portion on a trip piece 16, which will be described later, and is rotatable.

The trip piece 16 is attached to a molded shaft formed in the shape of a protrusion on the base 1, and the protrusion 18 at the other end can be rotated counterclockwise by the actuation displacement of the instantaneous iron piece 10 due to the bending of the bimetal 4, and 19 is a trip piece. 16 is a coiled spring that always biases clockwise, and 20 is a closing piece connected to the movable piece 5 and the plate pressure spring 14, and is made to be able to slide up and down through a groove provided in the base 1, and is always attached to a protruding shaft provided in the base 1. The U-link 1 is biased upward by the wound cut-off spring 21, and 22 is the guide groove of the U-link 15 provided in the base 1.
5, it is preferable that one leg that engages with the lever part 13 is short, and the other leg that engages with the guide groove 15 is long and formed in an inverted N shape so that it does not come off from the groove. 24 is an adjustment screw for adjusting the operating point of the bimetal 4 and the trip piece 16; and 25 is the circuit breaker; when resetting the circuit breaker, the other end of the plate pressure spring 14 is connected to the claw portion 17 of the trip piece 16;
This is a pillar part provided on the base 1 to facilitate engagement with the base 1.

When the circuit breaker is closed, the current flows through the power terminal 2, fixed contact 7, movable contact 6, movable piece 5,
Flows through the circuit of lead wire 9, bimetal 4, and load terminal 3,
If the current becomes an overcurrent, the bimetal 4 bends to the right, and the tip of the adjustment screw 24 presses the protrusion 18 of the trip piece 16 via the momentary iron piece 10, rotating the trip piece 16 counterclockwise. The plate pressure spring 1 is engaged with the pawl 17.
4 is removed, the input piece 20 is pulled up, and the movable piece 5 rotates, resulting in the state shown in the second figure, the contacts 6 and 7 are opened, and the circuit is opened.

In the case of a short circuit current, a large current flows through the lead wire 9 wound several times around the U-shaped magnetic core 8, generating a large electromagnetic force that momentarily attracts the iron piece 10, causing the trip piece 16 to move counterclockwise. It rotates and opens contacts 6 and 7 in the same way as when there is an overcurrent.

Next, when re-closing, bundle 12
When rotated counterclockwise, one end of the plate pressure spring 14 and the UI
The connection part with the junction 15 is guided by the guide groove 22 and pulled up, and the bimetal 4 is cooled and bent back due to the opening of the electric circuit, and the instantaneous iron piece 10 and the trip piece 16 are also restored to their original state. The middle part of the plate pressure spring 14 is the column part 2 of the base 1.
5, the upward movement is restricted, and the other end of the plate pressure spring 14 re-engages with the claw portion 17 of the trip piece 16, resulting in the reset state shown in Figure 3. From this state, the bundle 12 is rotated clockwise. Then, the tip of the plate pressure spring 14 is bent clockwise around the claw portion 17 by the UIJ link 15 and the guide groove 22, and the insertion piece 20 connected to the movable piece 5 is bent by the plate pressure spring 14. The contact spring 14 is pulled downward against the spring 21, and the contacts 6 and 7 are closed, and at the same time, the plate pressure spring 14 applies contact pressure to the contacts 6 and 7.

In this case, the UU link 15 to the lever part 13 of the bundle 12
The insertion point, that is, the bearing point is between the rotation center of the bundle 12 and the plate pressure spring 1.
Bundle 12 comes to the left side of the X-Y line connecting the connection point of 4 and UIJ link 15, that is, beyond the put point.
When the bundle receives the rotational force in the clockwise direction, the bundle will be in the inserted state shown in FIG. 1 without being reversed.

In addition, when opening and closing the bundle 12 by normal operation, if the bundle 12 is rotated counterclockwise from the state shown in FIG. Since the state shown in the third figure is reached by the link, the closing piece 20 and the movable piece 5 are pulled up and the circuit is opened, and if the bundle 12 is rotated clockwise from this state, the circuit is reclosed after the overcurrent operation as described above. The circuit is closed in a similar manner.

As mentioned above, this design has a very small number of parts and a simple structure, and since all the assembly is an insertion type and no separate metal shaft is used, the circuit floor is much lower than the unit cost of parts and the number of assembly man-hours. It is possible to provide a circuit breaker.

[Brief explanation of drawings]

Figures 1 to 3 show internal side views of the small circuit breaker of the present invention in different states. Further, FIG. 3 shows an open circuit state by normal opening/closing bundle operation and a state in which the state shown in FIG. 2 is reset by opening/closing bundle operation. 1 is a base, 2 is a power terminal, 3 is a load terminal, 4 is a bimetal, 5 is a movable piece, 8 is a U-shaped fixed core, 9 is a lead wire, 10 is an instantaneous iron piece, 11.19 is a coiled spring, 12 is Opening/closing bundle, 14 is a plate pressure spring, 15 is a U link, 16 is a trip piece, 20 is a closing piece, 21 is a cutoff spring, and 22 is a guide groove.

Claims (1)

[Scope of utility model registration request] A base 1, a power terminal 2 having a fixed contact 7, a square terminal 3 having a bimetal 4 fixed to one end, a movable piece 5 that is rotatable around its left end and has a movable contact 6 at its tip, and has a U-shape. a fixed iron core 8, a lead wire 9 wound around the U-shaped fixed iron core 8 and connected at both ends to the bimetal 4 and the movable piece 5, and an instantaneous iron piece 1 rotatably attached to the base 1.
0, a coiled spring 11 that biases the instantaneous iron piece 10,
Opening/closing handle 1 rotatably attached to the base 11
2, a trip piece 16 that is attached to the base 1 and has a claw part 11 at one end and a protrusion 18 that opposes the instantaneous iron piece 10 at the other end, a winding spring 19 that biases the trip piece 16, and one end. is engaged with the claw portion 17 of the trip piece 16, and the other end is connected to the UIJ link 15 to interlock with the opening/closing handle 12; and a plate pressure spring 14 that is attached to the base 1 and is connected to the UIJ link 15. The small circuit breaker is equipped with a guide mechanism 22 for guiding, a closing piece 20 connected to the movable piece 5 and the plate pressure spring 14 and capable of sliding up and down, and a cutoff spring 21 for biasing the closing piece 20 upward.