JPH06180149A - Positive temperature coefficient thermistor heat generating element - Google Patents

Abstract

PURPOSE:To provide a positive temperature coefficient thermistor heat generating element in which a heat radiating effect is kept constant, its efficiency is well adapted and a high heat generating amount can be secured. CONSTITUTION:Positive temperature coefficient thermistor elements 1 are held and fixed by heat radiators 2 while a plurality of sides of heat radiation plates 2b in the shape of a triangular prism being equally spaced apart on metallic plates 2a, a voltage is applied to the heat radiating elements 2, resulting in that the voltage is added to the positive temperature coefficient thermistors 1 so as to generate heat. Heat generated by heat generating operation is transmitted to heat radiator plates 2b through metallic plates 2a and at that time as air is passed through the heat radiators 2, the heat at the heat radiating plates 2b of the heat radiators 2 is radiated due to a thick plate thickness at the portion foxed to the metallic plates 2a and concurrently the heat is transmitted to a thin end of plate and only the heat radiation is carried out at the thin plate thickness. Thereby, it is possible to take out the hot air from the entire heat radiators 2 and to increase a heat generating amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PTC thermistor heating element used for heating a fluid such as air such as a warm air heater.

[0002]

2. Description of the Related Art Since a positive temperature coefficient thermistor is a semiconductor ceramic whose resistance value rises rapidly at a certain temperature, it has a self-temperature control action. When a voltage is applied to it and it is used as a heating element, its surface temperature rises. It is generally well-known that it is a convenient heating element because it does not change much and does not heat.

Further, when this heating element is used as a heater for heating a fluid such as air, it does not become red heat even when the passage of the fluid is stopped and can be used as a safe heater. It is generally well known that the effect can be sufficiently exhibited by fixing the heat radiator to the positive temperature coefficient thermistor and increasing the surface area of the heat radiator in order to increase the heat generation amount by increasing It is a thing.

FIG. 2 is a perspective view showing the structure of the conventional PTC thermistor heating element. Reference numeral 1 denotes a PTC thermistor having electrodes (not shown) provided on both principal planes, and a plurality of adjacent PTC thermistors are provided. The pieces are arranged. Reference numeral 3 denotes a heat radiator formed by bending a thin aluminum plate into a corrugated shape, and fixing an electrode plate made of an aluminum plate on one surface by brazing or the like so as to also serve as a conduction path. The other surface of the radiator 3 is closely fixed to both main planes of the positive temperature coefficient thermistor 1.

When a voltage is applied to each of the heat dissipating members 3 which also serve as a conduction path of the PTC thermistor heating element constructed as described above, this voltage is applied to the PTC thermistor 1 to generate heat. The generated heat is transmitted to each of the radiators 3, and when a fluid such as air is added to one of the radiators, warm air can be obtained from the opposite side.

FIG. 3 is a perspective view showing another example of a conventional PTC thermistor heating element, and 1 is a PTC thermistor in which electrodes are provided on both main planes, and a plurality of them are arranged adjacent to each other. Has been done. Reference numeral 4 denotes a heat radiator formed by processing aluminum by extrusion molding or the like, and is constituted by closely fixing the heat radiator 4 to both main planes of a plurality of PTC thermistors 1 arranged adjacent to each other. ing. Since the operation of the PTC thermistor heating element is similar to that of the conventional PTC thermistor heating element described in FIG. 2, the description thereof is omitted.

[0007]

However, in the above-mentioned conventional structure, when an attempt is made to increase the heat generation amount, a method of enlarging the entire radiator 3 or 4 in order to increase the surface area of the radiator 3 or 4, Radiator 3 or 4
There is a method to increase the heat capacity by increasing the plate thickness of
Alternatively, the method of increasing 4 is effective in increasing the ventilation area in the height direction rather than increasing it in the ventilation direction.

However, the heat from the PTC thermistor 1 is
It is transmitted from the surface to which the radiator 3 or 4 is fixed, and the radiator 3
Or it is transmitted to the whole 4. At that time, when the air passes through the vent hole, the heat from the PTC thermistor 1 is transferred to the entire radiator 3 or 4, and at the same time, the radiator 3 or 4 radiates heat, so that the temperature of the portion far from the PTC thermistor 1 is increased. There was a problem that the heat dissipation effect became worse because the temperature was lower than that of the near part. Furthermore, the effect becomes worse as the radiator 3 or 4 is made larger in order to increase the amount of heat generation, and there is a problem that the amount of heat generation cannot be increased for the shape effect.

In the method of increasing the plate thickness, the above problem is solved and the heat conductivity is increased so that the heat can be transmitted to the entire radiator 3 or 4, but it is heavy and difficult to process. There was a problem that the cost would be high.

The present invention solves the above problems and provides a highly reliable positive temperature coefficient thermistor heating element which maximizes the heat radiation effect of the heat radiation element, has a large heat generation amount, and is small in size and lightweight. That is the purpose.

[0011]

In order to solve this problem, a positive temperature coefficient thermistor heating element of the present invention is a positive temperature coefficient thermistor in which electrodes are formed on both main planes and which are arranged alone or in a plurality. The heat radiators connected to both main planes are formed by connecting a plurality of triangular or trapezoidal heat sinks to a metal plate at equal intervals to form a ventilation part, and connecting the heat sinks to both main plates of the positive temperature coefficient thermistor. It is configured by being connected to each plane.

[0012]

With this structure, when a voltage is applied to the positive temperature coefficient thermistor and air is passed through the ventilation part of the radiator, the positive temperature coefficient thermistor generates heat, and the heat is transmitted to the air through the ventilation part of the heat radiator. , Can be heated by hot air.
Moreover, since the shape of the heat radiator is made thinner toward the side farther from the heat generating portion, the heat radiation effect can be made constant, and a heat generating body with a large heat generation and high efficiency can be obtained.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A PTC thermistor heating element according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the structure of a PTC thermistor heating element according to an embodiment of the present invention. Reference numeral 1 is a square PTC thermistor having electrodes (not shown) formed on both principal planes by aluminum spraying or the like. Reference numeral 2 denotes a metal plate 2a made of a thin aluminum plate and a plurality of sides of a heat radiating plate 2b made of a triangular prism of aluminum arranged at equal intervals to form a ventilation part 2c and fixed by brazing to also serve as a conduction path. The heat radiator 2 is formed on the main surface of the positive temperature coefficient thermistor 1.
Is fixed by an adhesive.

The operating principle of the PTC thermistor heating element of the present invention having the above-described structure will be described below. When a voltage is applied to each heat radiator 2, the heat radiator 2 serves as a conducting path, and a voltage is applied to the positive temperature coefficient thermistor 1 to generate heat. The heat is transmitted to the metal plate 2a of the radiator 2 and further to the radiator plate 2b. At that time, the ventilation part 2 provided in the radiator 2
When air is passed through c, the heat of the heat radiating plate 2b of the heat radiating body 2 is radiated at the same time as the thickness of the portion fixed to the metal plate 2a is increased, and at the same time, the heat is transmitted to the thin end portion, Only the heat is dissipated at the thin end. Thereby, the warm air can be taken out from the entire radiator 2 and the amount of heat generation can be increased.

In the present embodiment, the shape of the heat dissipation plate 2b is a triangle, but in addition to this, any shape can be used as long as the ventilation part 2c can be formed at the end by a trapezoid or a semicircle. Needless to say, it does not matter.

[0016]

As described above, according to the present invention, by fixing a positive temperature coefficient thermistor with a heat radiator having one side of a triangle fixed on a metal plate, heat can be efficiently transmitted to the end of the heat radiator. It is possible to realize an excellent positive temperature coefficient thermistor heating element that can obtain a large amount of heat generation even if it is small.

[Brief description of drawings]

FIG. 1 is a perspective view showing a PTC thermistor heating element according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a conventional PTC thermistor heating element.

FIG. 3 is a perspective view showing a conventional PTC thermistor heating element.

[Explanation of symbols]

 1 Positive temperature coefficient thermistor 2 Radiator 2a Metal plate 2b Radiator 2c Ventilation part

Claims (1)

[Claims] 1. A PTC thermistor having electrodes formed on both main planes and arranged alone or adjacently to each other, a metal plate respectively coupled to both main planes of the PTC thermistor, and this metal plate. A positive temperature coefficient thermistor heating element having a heat radiation member formed of a heat radiation plate having a triangular or trapezoidal cross section, which are arranged adjacent to each other to form a ventilation part and are coupled to each other.