JPH0256770B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a temperature switch.

Conventionally, this type of temperature switch has a fixed contact 16' fixed to an external terminal 6' as shown in FIG. 8, and a free end of a movable contact spring 23' having one end fixed to a movable spring fixing base 9'. Movable contact 2 fixed on
6' is provided so as to be contactable, and an inverted bimetal 18' disposed below the movable contact spring 23' is provided so as to come into contact with the protrusion 11' on the movable spring fixing base 9' when inverted. . Therefore, when the ambient temperature reaches the set temperature, the inverted bimetal 18' is warped in the opposite direction, and its center portion comes into contact with the protrusion 11', and the movable contact spring 23' is pushed up, so that the fixed contact 16' As a result, the movable contact 26' opens and separates.

However, since the above-described configuration uses only a single inverted bimetal 18', damage to the inverted bimetal 18' and fixed contact 16' and movable contact 2 are avoided.
There was a risk that the temperature switch would become inoperable due to contact welding with 6'.

The present invention aims to eliminate the above-mentioned drawbacks and provide a temperature switch with multiple safety features.

The temperature switch of the present invention will be explained below with reference to the drawings.

1 to 6 show an embodiment of the temperature switch of the present invention. In the figures, a box-shaped housing 1 is open at one end, and there are formed on the inner surfaces of both side walls of the housing 1. The switch body 3 is accommodated with both side edges fitted into the groove 2. The base 4 of the switch body 3 is made by punching a flat metal plate by press working, bending and doweling to form a switch board base, and then molding it with synthetic resin, and then forming parts corresponding to external terminals. A portion corresponding to the movable contact spring fixing plate is formed independently.

To be more specific, the base 4 has a longitudinal base 5 made of molded synthetic resin, and at one end of the base 5 there is a pair of main external terminals 6 extending in the length direction.
The inner end of the auxiliary external terminal 7 is buried therein, and most of the movable spring fixing base 9, which extends in the length direction and has a stepped portion 8 at its free end, is buried in the other end. Also, approximately in the center of the platform 5 is a low protruding platform 1.
0 is bulged out, a small push-up projection 11 is erected upward, a wall 12 that can close the open end surface of the housing 1 is bulged upward at one end, and a cylindrical column is provided at the center of the other end. A support protrusion 13 is provided upright, and semi-cylindrical locking protrusions 14 are provided on the other end edge at equal distances from the support protrusion 13.
15 are erected. In addition, the main external terminal 6
A main fixed contact 16 and an auxiliary fixed contact 17 having different sizes are fixed to the inner end of the auxiliary external terminal 7 located inside the wall 12.

On the other hand, on the base 4, a concave curved main reversing bimetal 18 and an auxiliary reversing bimetal 19 having different operating temperatures are mounted vertically. The lower auxiliary reversing bimetal 19 operates at a relatively higher set temperature,
That is, it operates at an abnormally high temperature. Further, the main and auxiliary inversion bimetals 18 and 19 have a circular shape when viewed from above, and their respective bases are connected to the support protrusion 1.
3 and the locking projection 14 or 15, and is engageable with the support projection 13 and the locking projection 14 or 15.
0 and 21, 21 are formed. Therefore, when the notches 20, 20 and 21, 21 are engaged with the support protrusion 13 and the locking protrusion 14 or 15, the main and auxiliary inverted bimetals 18 and 19 are connected to each other on the base 4. Alternatively, the locking protrusion 19 extends toward the edge opposite to the edge where the locking protrusion 14 or 15 is located. That is, most of the auxiliary inversion bimetals 18 and 19 overlap each other vertically when viewed from above, and their tips intersect with each other and extend toward opposite edges of the base 4. Furthermore, a hole 22 is drilled in the center of the auxiliary reversing bimetal 19 through which the small push-up projection 11 of the base 4 can be inserted, and this push-up small projection 11 allows the main and auxiliary reversing bimetals 18 and 19 to be mutually inserted. spaced apart.

The proximal end of the movable contact spring 23 is preferably fixed to the stepped portion 8 of the movable spring fixing base 9 via a dowel. The movable contact spring 23 is bifurcated to form a main contact spring part 24 and an auxiliary contact spring part 25.
A main movable contact 26 and an auxiliary movable contact 27, which are capable of contacting the main and auxiliary fixed contacts 16 and 17 of the main and auxiliary external terminals 6 and 7, respectively, and which are different in size from each other are fixedly provided at the free ends of the terminals. Further, the main and auxiliary contact spring parts 24 and 25 are cut and raised with a main protrusion 28 and an auxiliary protrusion 29 that extend downward and have different lengths, and are similar to the tips of the main and auxiliary inverted bimetals 18 and 19. It is provided so that it can come into contact with it. That is, the main protrusion 28 that can come into contact with the main inversion bimetal 18 located at the upper position is short, and the auxiliary protrusion 29 that can come into contact with the auxiliary inversion bimetal 19 located at the lower position is provided long. Further, a blocking tongue piece 31 is extended from the side edge of the auxiliary contact spring portion 25 to rest on a downward movement blocking step portion 30 formed in the base 4 during upward movement. In addition, the open end of the housing 1 housing the switch body 3 is filled with a sealing adhesive 32.

Further, the operation of the temperature switch according to the present invention will be explained. In the temperature switch of the present invention, the electrical circuit includes the main external terminal 6, the main fixed contact 16, the main movable contact 26, the main contact spring part 24, the auxiliary contact spring part 25, the auxiliary movable contact 27, the auxiliary fixed contact 17, and the auxiliary external terminal 7. It is formed. When the ambient temperature of the device to which the temperature switch is currently attached reaches the relatively low first set temperature at which the main reversing bimetal 18 is reversed, the main reversing bimetal 18 operates in reverse and the main contact is The spring portion 24 is pushed up. As a result, the main movable contact 26 of the main contact spring part 24 is separated from the main fixed contact 16 attached to the main external terminal 6, and the contact is placed in the open state.This is repeated to open and close the contact as appropriate. Ru. At this time, the auxiliary reversing bimetal 19 is not reversed, and the auxiliary fixed and movable contacts 17 and 27 continue to be closed, but the electrical circuit is interrupted.

On the other hand, when a device equipped with a temperature switch reaches a relatively high second set temperature at which the auxiliary reversing bimetal 19 is reversed due to cracking of the main reversing bimetal 18 or welding of the main fixed and movable contacts 16 and 26, for example, The auxiliary reversing bimetal 19 performs a reversing operation, and the auxiliary contact spring portion 25
is pushed up, the auxiliary movable contact 27 of the auxiliary contact spring portion 25 separates from the auxiliary fixed contact 17 attached to the auxiliary external terminal 7, and the contact is closed.

In this case, the main and auxiliary inverted bimetals 18 and 19 are arranged above and below, and the main and auxiliary inverted bimetal 1
Main and auxiliary contact spring parts 2 linked with 8 and 19 respectively
4 and 25 are provided with short main protrusions 28 and long auxiliary protrusions 29, respectively, so that the main and auxiliary inverted bimetal 1
8 and 19 from each other, the main reversing bimetal 18 can freely reverse from the position shown in FIG. 4 to the position shown in FIG. 19 is also the 4th
As shown in FIG. 6 from the position shown in the figure, the auxiliary contact spring part 25 can be driven without being influenced by the upper main reversing bimetal 18.

FIG. 7 shows another embodiment of the present invention, in which the main inversion bimetal 18a
is disposed on the lower side, the auxiliary inversion bimetal 19a is disposed on the upper side, and the main protrusion 2 of the main contact spring portion 24a
8a is long, and the auxiliary protrusion 2 of the auxiliary contact spring part 25a
9a is formed short. Therefore, the operability of the auxiliary inversion bimetal 19a is further improved. Other configurations and operations are similar to those of the above-described embodiment.

According to the temperature switch of the present invention configured as described above, a protrusion directed downward is provided on the lower surface of the main contact spring constituting the movable contact spring, and a protrusion directed downward is also provided on the lower surface of the auxiliary contact spring. are provided, one of the protrusions is arranged so as to be able to come into contact with the main reversing spring, and the other protrusion is provided so that it can come into contact with the auxiliary reversing spring, so that each reversing bimetal can be connected to the main or auxiliary reversing contact spring. When operating, the movement of the inverted bimetal is directly transmitted through the protrusion, so the contact spring is smoothly driven and the operation is highly reliable.

Further, according to the present invention, the temperature switch can be made thinner by arranging two main and auxiliary reversing bimetals that operate each movable contact spring independently under the movable contact plate. It has the effect of being able to measure the

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of one embodiment of the temperature switch of the present invention, Fig. 2 is an internal plan view, Fig. 3 is an internal side view, and Fig. 4 is a cross section taken along the - line in Fig. 2. Figures 5 and 6 are explanatory diagrams of the same operation.
The figure is a sectional view of another embodiment of the present invention, and FIG. 8 is a simplified side view of a conventional temperature switch. DESCRIPTION OF SYMBOLS 1... Housing, 2... Groove, 3 ... Switch body, 4... Base, 5... Base part, 6... Main external terminal, 7... Auxiliary external terminal, 8... Step part, 9... ...Movable spring fixing base, 10...Protruding base part, 11...Push-up small projection, 12...Wall part, 13...Support protrusion, 1
4, 15... Locking protrusion, 16... Main fixed contact, 1
7... Auxiliary fixed contact, 18... Main reversing bimetal, 19... Auxiliary reversing bimetal, 20, 21...
...Notch, 22...hole, 23...movable contact spring,
24...Main contact spring part, 25...Auxiliary contact spring part, 26...Main movable contact, 27...Auxiliary movable contact, 28...Main protrusion, 29...Auxiliary protrusion, 30...
...Downward movement blocking step, 31...Blocking tongue piece, 32...Adhesive.

Claims (1)

[Claims] 1 A base, a plurality of external terminals held by the base and attached with fixed contacts, and a movable contact that can make contact with the fixed contacts are attached, and are approximately U-shaped and have a main contact spring and an auxiliary contact in the same plane. A movable contact spring having a contact spring, a movable spring fixing plate held on the base and holding the movable contact spring, and two main and auxiliary reversing bimetals that independently operate each of the movable contact springs. In a temperature switch having a double protection function for one circuit, in which the movable contact plate is stacked under the movable contact plate and two bimetal sheets are inserted in series with respect to the electrical circuit to be opened, the movable contact spring is configured. A protrusion facing downward is provided on the lower surface of the main contact spring, and a protrusion facing downward is also provided on the lower surface of the auxiliary contact spring. A temperature switch characterized in that the protrusion is provided so as to be able to come into contact with an auxiliary reversing spring.