JPS5933141Y2 - Trip-free bimetal switch - Google Patents

Description

[Detailed description of the invention] The present invention relates to a new structure of a trip-free type bimetal switch.The feature is that it is trip-free despite its extremely simple structure due to the combination of parallel links and molded cams. The present invention provides a bimetallic switch structure that achieves this.

The switch of the present invention will be explained by way of an example.

A metal fitting 14 is press-fitted into the upper part of the recessed part 13 of the case 12 formed of an electrically insulating material, and a bimetal 15 is attached to the metal fitting.
Fix by resistance welding, etc.

The bimetal 15 has a U between the straight portion 16 and the free end 18.
When the curved portion 17 is formed, a bimetal heater 20 is inserted into the curved portion and heated through the terminals 1 and 2.

The tip of the bimetal is a latch 19.

Further, the bimetal 15 is arranged in the space 34, and the molded cam 26 is loosely fitted on the shaft 31 to the other end of the U-shaped parallel link 22, one end of which is loosely fitted on the shaft 23.

In addition, an insertion hole 32 is provided in the upper part of the case, and a reset button 25 is arranged so that the tip of the reset button presses the pressing surface 29 of the molded product cam.

When the molded cam is pressed by the reset button, the cam tip 30 engages the bimetallic tip latch 19.

Further, a link pin 28 for opening/closing operation is provided on the molded product cam, and the contact 10 on the conductive spring γ provided on the terminal 4 is in strong contact with the contact 9 side on the conductive spring 6 provided on the terminal 3. Place it so that

The contact 11 on the conductive spring 8 provided on the terminal 5 is placed apart from the contact 10.

When this bimetal switch is energized for a certain period of time or more, the bimetal is heated by the heater 20, and the bimetal tip latch portion 19 is displaced in the opening direction, disengaging from the tip portion 30 of the molded product cam 26, and the parallel link 22 and The molded product cam 26 is displaced from the position shown in FIG. 1 to the position shown in FIG. Upper contact 11
The purpose of contact switching is achieved by moving to .

This is a normal operating state, but even if the user intentionally holds down the manual reset button 25 and tapes it to prevent it from returning, the bimetal tip latch will release after a certain period of time. The engagement between the part 19 and the tip 30 of the molded product cam is disengaged, and the molded product cam 26 rotates in this position due to the repulsive force of the conductive spring I, and the contacts 10 and 9 are separated, and conversely, the contacts 10 and 11 are separated. Since they are in contact, the so-called trip-free mechanism is not damaged.

In addition, to restore the bimetal switch once activated, the manual reset button 25 is pressed, but at this time, the link pin 28 for opening/closing operation at the tip of the molded product cam 26 is connected to the contact point 9.
The contact point 10 is pushed in while being separated, and after the other end portion 30 of the molded product cam and the bimetal tip latch portion 19 are engaged, the pressing force of the manual reset button is removed.
For the first time, contacts 10 and 9 are brought into contact.

The screw 33 attached to the metal fitting 14 is for adjusting the bimetal operation, and the spring 21 attached to the bimetal latch portion 19 is for stabilizing the heater 20 on the bimetal.

[Brief explanation of drawings]

The drawings show one embodiment of the switch of the present invention, and Figure 1 is a front view with the cover removed and in the latched state;
FIG. 2 is a diagram showing the state in which the above latch is released, FIG. 3 is an exploded perspective view of related parts for explaining the latch mechanism, and FIG. 4 is a terminal circuit diagram. 1.2, 3, 4.5 are terminal fittings, 6, 7, 8 are conductive springs, 9, 10.11 are contacts, 12 is a case, 13 is a case recess, 14 is a metal fitting, 15 is a bimetal, 16 1 is a bimetal straight part, 17 is a bimetal U-shaped groove part, 18 is a bimetal free end, 19 is a bimetal latch part, 20 is a bimetal heating heater, 21 is a spring, 22 is a parallel link, 23 is a shaft, and 24 is a spring , 25 is a manual reset button, 26 is a molded product cam, 27 is a hole, 28 is a link pin for opening/closing operation, 29 is a pressing part, 30 is a locking part, 31 is a shaft, 3
2 is an insertion hole, 33 is a small screw, and 34 is a space.

Claims (1)

[Scope of utility model registration request] A metal fitting provided on the upper surface of the inside of the case; one end is fixed to the metal fitting, the middle part is formed into a substantially U-shape, and a bimetal heating heater is embedded inside the U-shape, and the other end is a free end. , a bimetal plate on which a latch portion is formed, a parallel link formed in a U-shape by placing the bimetal in a space, a pivot hole formed in the U-shaped base of the parallel link, and a pivot hole in the parallel link. a shaft loosely fitted into the case and supported by the case;
a spring provided on the shaft and biasing the U-shaped base of the parallel link; a pivot hole loosely fitted through the shaft into a hole in the bifurcated end of the parallel link; and a bimetal latch at one end. A molded product cam having a locking part that engages with the part and a link pin for opening and closing operation at the other end, a manual reset button that presses the rotation base of the former molded product cam, and a link pin that operates the opening and closing part of the molded product cam. a first electric contact piece that is always energized; a second electric contact piece that faces the first electric contact piece and is always spaced apart from the first electric contact piece; a second electric contact piece that faces the first electric contact piece and is always in contact with the first electric contact piece; Trip-free bimetallic switch consisting of a third electrical contact piece.