JPS6260201A - Positive temperature coefficient thermistor - 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 Field of Industrial Application The present invention relates to a positive temperature coefficient thermistor device used in non-contact switches such as motor starting and degaussing circuits.

Conventional technology Conventionally, a positive temperature coefficient thermistor device is constructed by loading a positive temperature coefficient thermistor into an insulating case. A pair of spring terminals are fixedly inserted through the insulating case, and the positive temperature coefficient thermistor is clamped and fixed by the spring terminals. method is used.

Below is a theory 2 about the conventional positive temperature coefficient thermistor device.
to clarify.

FIG. 3 shows a conventional thermistor device, in which a positive temperature coefficient thermistor is sandwiched between the tips of a pair of metal terminals 9, each of which has at least the tips formed of a spring material, in the inner space of an insulating case 8 that is shaped like a tip. 10 is arranged, the metal terminal 9 is fixed through an insulating cover 11, and this insulating cover 11 is attached to the insulating case 8 by a beam bet 13.

The operation of the positive temperature coefficient thermistor device configured as above will be described below.

When power is applied to the PTC thermistor 10 through the metal terminal 9, the PTC thermistor 1Q self-heats, switches at one Curie temperature, and its resistance rises rapidly.The self-temperature control action maintains the balance between heat generation and heat radiation, resulting in consumption. Power becomes stable.

Problems to be Solved by the Invention However, the above conventional configuration had the following problems.

First, the heat from the positive temperature coefficient thermistor 10 is easily transferred to the metal terminal 9, the insulating case 8, the insulating cover 11, etc.

Since K heat is dissipated, the self-temperature control action of the PTC thermistor 1o increases the amount of heat generated and increases power consumption, which is uneconomical. In addition, the positive characteristic server star 1o has a metal terminal 9
The positive temperature coefficient thermistor 1 is held in place using its spring properties.
0 between the metal terminals, the positive temperature coefficient thermistor 10
The electrode surface is easily damaged by the metal terminal 9, which not only makes assembly difficult, but also requires selection of a spring material, increasing costs. Furthermore, heat radiation from the positive temperature coefficient thermistor 1o to the metal terminal 9 is also large, which causes a temperature distribution difference in the positive temperature coefficient thermistor 1Q, resulting in frequent accidents such as cracking due to thermal strain.

SUMMARY OF THE INVENTION An object of the present invention is to provide a positive temperature coefficient thermistor device that can solve the problems of the conventional method.

Means for Solving the Problems In order to achieve this object, a positive temperature coefficient thermistor having a metal terminal in contact with the electrode surface of the 'iE characteristic memistor device of the present invention is covered with a heat insulating member having insulation and elasticity, and the above-mentioned A heat insulating member is press-fitted and housed in an insulating case.

Function: With this configuration, it is possible to obtain a positive temperature coefficient thermistor which is economical, has a stable self-temperature control function, consumes little power, is easy to assemble, and has high safety.

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

1 and 2 illustrate a positive temperature coefficient thermistor according to one embodiment of the present invention. With the metal terminals 3 electrically connected to the electrodes 2 on both sides of the PTC thermistor 1, the PTC thermistor 1 and the metal terminals 3 are inserted into the recess 41 provided in the insulating and elastic heat insulating member 4. Assemble. The assembled PTC thermistor is press-fitted and housed in an insulating case 5 formed to have an inner diameter smaller than the outer diameter of the heat insulating part 4. Furthermore, the metal terminal 3 is fixed through an insulating cover 6 disposed on the bottom wall of the insulating case 5, and the insulating cover 6 is fixed to the insulating case 5 with rivets 7 to seal the PTC thermistor 1 and the heat insulating member 4. The heat insulating member 4 is made of sponge-like silicone rubber with many air bubbles inside its thickness, and has a very high heat insulating effect.

The operation of the positive temperature coefficient thermistor of this embodiment configured as described above will be explained below.

First, the heat from the PTC thermistor 1 is suppressed by the action of the heat insulating member 40 covering the PTC thermistor 1 and the metal terminal 3 electrically connected to the PTC thermistor 1. Since the self-temperature control function generates less heat, power consumption can be kept low. Oh, it's a positive characteristic covered with insulation material 4 ~ Mr. 1
Since the terminal 3 and the metal are constantly pressed together due to the elasticity of the V heat insulating member 4, the metal terminal 3 does not particularly require spring properties, and any material can be selected, making it possible to use the # family, which is highly workable and inexpensive. In addition, since the heat insulating member 4 is simply press-fitted into the insulating case 6, it is easy to assemble. Furthermore, the electrical contact between the positive temperature coefficient thermistor 1 and the metal terminal 3 is also good, highly reliable, and reliable.

Further, the heat from the PTC thermistor 1 is less likely to be radiated to the heat insulating member 4, the difference in temperature distribution of the PTC thermistor 1 is reduced, and problems such as cracking due to thermal distortion are completely eliminated. Note that even if the metal terminal and the electrode surface of the PTC thermistor are connected mechanically, such as by soldering, they are protected by the elasticity of the heat insulating member, so there is no deterioration of the connection due to vibrations, shocks, etc.

Effects of the Invention According to the present invention, a metal terminal of a positive temperature coefficient thermistor is covered with a heat insulating member in a state in which the electrode is in contact with the electrode, and the metal terminal is press-fitted into an insulating case and stored, and heat dissipation of the positive temperature coefficient thermistor is suppressed by the heat insulating member. Therefore, not only can the self-temperature control function be stabilized and the economic effect of reducing power consumption can be obtained, but also cracking due to thermal distortion does not occur because the difference in temperature distribution of the thermistor is suppressed. Furthermore, since no spring material is used for the metal terminal, the electrode surface of the positive characteristic mister is not damaged, and the electrical contact is good and highly reliable.

In addition, since the structure is simple, assembly work is easy and costs can be reduced, making it possible to realize an excellent positive temperature coefficient thermistor with many advantages.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a PTC thermistor device according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the same embodiment, and FIG. 3 is a sectional view of an example of a conventional PTC thermistor device. 1. - Positive characteristic thermistor, 2 - Electrode, 3 - Metal terminal, 4 - Heat insulation member, 5 Insulation case, 6 -
...Insulation cover, 7- rivet.

Claims (1)

[Claims] A positive temperature coefficient thermistor device, characterized in that a positive temperature coefficient thermistor having a metal terminal electrically connected to an electrode surface is covered with a heat insulating member having insulation and elasticity, and the heat insulating member is press-fitted into a case and housed. .