JPS6126175B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature switch that combines the convenience of a resettable temperature switch with the safety of a non-resettable temperature switch.

Overtemperature rise prevention devices are used in electrical equipment from the viewpoint of safety. Conventionally, this type of overtemperature rise prevention device includes a reversible type using bimetal,
There are non-resetting types that use fusible alloys, etc. The former has the advantage that it can be used repeatedly and is convenient because it automatically resets once the ambient temperature drops, but on the other hand, if the cause of the operation is not removed, it will repeatedly turn on and off. Then,
The drawback is that it can eventually lead to contact welding, which is dangerous. On the other hand, the latter has the advantage of being safe because it does not automatically return once it is activated, but on the other hand,
Even if it malfunctions during soldering, etc., it is a hassle to have to replace it.

Therefore, it would be advantageous if a temperature switch could be provided that combines the convenience of a resettable type with the safety of a non-resettable type.

Therefore, Utility Model Publication No. 14850, Utility Model Publication No. 1972-
Japanese Patent No. 51473 discloses a temperature switch that is both convenient and safe by combining a resettable temperature switch and a non-resettable temperature switch. However, all of these temperature switches are non-resettable temperature switches and use fusible alloys, and as the surface of fusible alloys oxidizes when left unused, the apparent melting point gradually rises and As the operating temperature gradually increases,
Not only is the operation unsafe and unreliable, but the melted fusible alloy also tends to cause re-conductivity and breakdown voltage failures.

A principal object of the present invention is to provide a temperature switch which combines the advantages of the above-mentioned revertible and non-returnable temperature switches, and which is safe, accurate and reliable in operation.

Another object of the present invention is to provide a highly accurate temperature switch that is easy to assemble and to test and inspect after assembly.

To summarize, the present invention includes a first spring electrode plate operated by a bimetal and a second spring electrode plate operated by a temperature-sensitive agent that melts at a specific temperature, housed in the same case, Moreover, the present invention is characterized in that these are incorporated into an insulating positioning member.

The above objects and other objects and features of the present invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 1 shows a cross-sectional view of one embodiment of the temperature switch of the present invention. FIG. 2 shows a longitudinal cross-sectional view taken along the line --- in FIG. FIG. 3 shows a longitudinal sectional view taken along the line --- in FIG. 1.

In the figure, 1 is a case, which is made up of a metal container 2 and an insulating sealing body 3. The sealing body 3 includes a plate material 4 made of a press board or the like, and an insulating sealant 5 made of an epoxy resin or the like deposited thereon. 6 is a dish-shaped bimetal that reverses its operation at a specific temperature, 7 is an insulating positioning member made of synthetic resin, etc., which has a through hole 8 in the center and a recess in which a temperature-sensitive agent 21, which will be described later, is partially housed. It has 9. Reference numeral 10 denotes a first spring electrode plate made of beryllium copper, phosphor bronze, etc., which has a contact 11 at one end and a pin 1 at the other end.
2 to the positioning member 7.
13 is a first Faston terminal made of brass or the like;
Its base 13a is electrically connected to the other end of the first spring electrode plate 11 by the pin 12 and is fixed to the positioning member 7, and the other end penetrates the sealing body 3 and is exposed to the outside. It has been derived. A second Faston terminal 14 is made of brass or the like, and its base 14a is fixed to the positioning member 7 by a pin 15, and the other end passes through the sealing body 3 and is led out. Reference numeral 16 denotes a second spring electrode plate made of beryllium copper, phosphor bronze, etc., one end of which is fixed to the positioning member 7 by a pin 18 having a fixed contact 17, and the other end fixed to the base of the second Faston terminal 14. 14a, and has a through hole 19 at a position corresponding to the through hole 8 of the positioning member 7 in the center. 24 is an insulating push rod made of ceramic or the like, which is inserted into the through hole 8 of the positioning member 7 and the second
The first spring electrode plate 10 is inserted through the through hole 19 of the spring electrode plate 16, and the reversal action of the bimetal 6 pushes up the first spring electrode plate 10 against its springiness.
Reference numeral 21 denotes a temperature sensitive agent made of an insulating chemical substance that melts at a specific temperature and is housed in the recess 9 of the positioning member 7, and its melting point is set higher than the operating temperature of the bimetal 6. A compression spring 22 is interposed between the free end of the second spring electrode plate 16 and the temperature sensitive agent 21, and its spring force is greater than that of the second spring electrode plate 16. Therefore, the second
The free end of the spring electrode plate 16 is strongly pressed into contact with the base 14a of the second Faston terminal 14 against the spring force. On the other hand, due to the spring force of the first spring electrode plate 10, the contact 1 at the free end thereof
1 is brought into strong pressure contact with the fixed contact 17.

In the above configuration, at room temperature, the bimetal 6 is convex downward as shown in the figure, and the contact 11 at the free end of the first spring electrode plate 10 is the fixed contact 1.
It is in contact with 7. On the other hand, since the temperature sensitive agent 21 is solid, the second spring electrode plate 16 is in contact with the base 14a of the second Faston terminal 14. For this reason, the first Faston terminal 13 - its base 13
a - first spring electrode plate 10 - contact 11 - fixed contact 17 - second spring electrode plate 16 - base 14a of second Faston terminal 14 - path of second Faston terminal 14; The Faston terminal 13 and the second Faston terminal 14 are electrically connected.

When the ambient temperature rises and exceeds the operating temperature of the bimetal 6, the bimetal 6 reverses in an upwardly convex manner as shown in the figure, and the push rod 20 pushes up the first spring electrode plate 10, so that the contact 11 becomes the fixed contact 17. The first Faston terminal 13 and the second Faston terminal 14 become non-conductive.

When the ambient temperature decreases due to the above operation, the bimetal 6 restores its convex shape downward in the figure, so the first spring electrode plate 10 restores itself due to its own spring force, and the contact 11 becomes the fixed contact 17. They come into contact again, and the first Faston terminal 13 and the second Faston terminal 14 become electrically connected again.

Here, before the bimetal 6 is restored,
If the cause of the activation of the bimetal 6, for example, a failure of an electrical device, has been resolved, the above-mentioned re-conducting state will be maintained. However, if the above-mentioned cause is not eliminated, the bimetal 6 will operate in reverse again. If this operation is repeated many times, the contact 11 will eventually weld to the fixed contact 17, and as the ambient temperature rises further and exceeds the melting point of the temperature-sensitive agent 21, the temperature-sensitive agent will melt. 21 melts. Then, the elastic force of the compression spring 22 is released, and the free end of the second spring electrode plate 16 separates from the base 14a of the second Faston terminal 14, causing the first Faston terminal 13 and the second Faston terminal to separate. A non-conducting state is established between the terminal 14 and the terminal 14. Due to this operation, even if the ambient temperature decreases, the temperature-sensitive agent 21 will not be restored to its original state, so that so-called non-returnable safety is ensured.

Thus, in a relatively low temperature range relative to an abnormal temperature rise, the bimetal 6 is reversed and the first spring electrode plate 10 is driven, which provides the convenience of a resettable temperature switch and is more In a high temperature range, the temperature sensitive agent 21 melts and the second spring electrode plate 16 operates to permanently open the circuit.
Non-returnable safety can be obtained. Here, temperature sensitive agent 2
Unlike fusible alloys, the melting point of No. 1 does not gradually rise due to oxidation even if left unused, so the operating temperature of the non-reset temperature switch does not gradually rise and can be safely and accurately maintained at a constant temperature. Not only does it work, but it also has the advantage of not causing undesired re-conductivity or a drop in withstand voltage after being melted, unlike fusible alloys.

Furthermore, since all the parts are attached to the positioning member 7, assembly is easy and the assembly accuracy is high. In addition, since it is also possible to measure the characteristics before forming the sealed body 3, it is also possible to adjust the characteristics, for example. Furthermore, since the temperature-sensitive agent 21 is housed in the recess 9 formed in the positioning member 7, positioning is not only easy and reliable, but also the amount of expensive temperature-sensitive agent 21 used can be reduced, reducing costs. There are also some advantages.

Although the present invention has been described with respect to a specific structural example, it is not limited to this structure in any way.
Various modifications are possible.

For example, although the Faston terminals 13 and 14 are shown as being integral with their bases 13a and 14a, the user of this type of temperature switch may require various directions for pulling out the Faston terminals. In such a case, if the terminal and the base are of an integrated structure to meet the needs of each user,
Substantially, many types of temperature switches must be manufactured, which is not only complicated but also causes an increase in cost. Therefore, in such a case, for example, a rising portion that penetrates the sealing body 3 and projects slightly may be provided on the base portions 13a and 14a, and the rising portion may be provided with a drawer direction that meets the wishes of each user. Faston terminals can be fixed.

Further, although the through hole 19 of the second spring electrode plate 16 is shown as a relatively small round hole that the push rod 20 passes through, if this is done, the second spring electrode plate 16
Since the spring force may be slightly insufficient due to the length of the spring electrode plate 16, the through hole 19 may be a long hole extending in the longitudinal direction of the spring electrode plate 16.

As described above, the present invention allows the first spring electrode plate, which is driven by the reversal action of the bimetal, and the second spring electrode plate, which is driven by the melting of the temperature-sensitive agent, to be connected to each other at all times. The thermosensitive agent is fixed to the positioning member so as to be in contact with the temperature switch, and the melting point of the temperature sensitive agent is set higher than the operating temperature of the bimetal, which provides the convenience of a resetting type temperature switch using a bimetal and the non-resetting type using a temperature sensitive agent. A temperature switch that has the safety of a temperature switch can be obtained. Moreover, unlike fusible alloys, temperature sensitive agents do not oxidize and gradually increase their apparent melting point when left unused, so the operating temperature gradually increases, causing unstable and uncertain operation. Moreover, the temperature-sensitive agent after melting does not cause undesired re-conduction or a decrease in withstand voltage. In addition, since all the parts are assembled to the positioning member, most of the assembly work can be done outside the case, which not only makes assembly work much easier, but also significantly improves assembly accuracy. Characteristics can be measured in the previous state, and characteristics can also be adjusted. Furthermore, since the temperature-sensitive agent is housed in a recess formed in the positioning member, not only is positioning easy and reliable, but the amount of expensive temperature-sensitive agent used is reduced, resulting in an excellent cost reduction. play.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one embodiment of the temperature switch of the present invention, FIG. 2 is a vertical cross-sectional view taken along the line - in FIG. 1, and FIG. 3 is a vertical cross-sectional view taken along the line - in FIG. be. DESCRIPTION OF SYMBOLS 1... Case, 6... Bimetal, 7... Positioning member, 9... Recess, 10... First spring electrode plate, 1
1, 17... Contact, 13, 14... Terminal, 16... Second
Spring electrode plate, 20... Push rod, 21... Temperature sensitive agent, 2
2... Compression spring.

Claims (1)

[Claims] 1 A case, an insulating positioning member housed in the case, a bimetal disposed on one side of the positioning member, and a first bimetal whose one end is fixed to the other side of the positioning member and which partially contacts the other side of the positioning member. A spring electrode plate, a second spring electrode plate, a push rod that penetrates the positioning member and applies a reversing force of the bimetal to the first spring electrode plate, and is bored on the other side of the positioning member. a temperature-sensitive agent made of an insulating chemical substance that melts at a specific temperature, and an elastic force stronger than that of the second spring electrode plate; 1. A temperature switch comprising: a compression spring, wherein the melting point of the temperature sensitive agent is set higher than the operating temperature of the bimetal.