JPH05251160A - Positive characteristic thermistor heating element - Google Patents

Abstract

PURPOSE:To provide a positive characteristic thermistor heating element to be used for various electric heater and drying machine, which can simplify the structure of these equipment and which can make these equipment compact and which can control the calorific value and the temperature of hot air easily. CONSTITUTION:An electrode 2a is provided in the back surface of a positive characteristic thermistor 1, and divided electrodes 2b, 2c are provided in the surface thereof, and terminals 4a, 4b, 4c, insulating sheets 5 and metal heat radiators 3 are laminated on these electrodes 2a, 2b, 2c, and they are fixed. Since the calorific value can be controlled by switching the electrifying of the terminals 4a, 4b, 4c, temperature of the hot air can be controlled by one positive characteristic thermistor heating element without using plural positive characteristic thermistor heating element, and an equipment such as a heater can be made compact.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive temperature coefficient thermistor heating element having a self-temperature controllability, which is used in a hot air heater, a dryer and the like.

[0002]

2. Description of the Related Art A positive temperature coefficient thermistor is a semiconductor ceramic having a property that its resistance value rapidly increases at a certain temperature (switching temperature) or higher. Therefore, when a voltage is applied, heat is generated, and when the switching temperature is exceeded, the temperature rise stops and a constant temperature is maintained. Therefore, it is widely applied as a safe heating element that does not overheat.

A conventional PTC thermistor heating element will be described below. FIG. 3 is a perspective view of a conventional PTC thermistor heating element, and FIG. 4 is an exploded perspective view thereof. In FIGS. 3 and 4, 1 is a positive temperature coefficient thermistor, and 2 is an electrode made of aluminum or the like applied to both surfaces thereof by a thermal spraying method or the like. Reference numeral 3 is a metal radiator made of a metal having a high thermal conductivity such as aluminum. A large number of through holes 3a are opened to increase the surface area, and the amount of heat generated can be increased by ventilation. Then, a plurality of positive temperature coefficient thermistors 1, terminals 4 such as an aluminum thin plate, and an insulating sheet 5 such as alumina, which are arranged on the same surface between the metal radiators 3, are sandwiched and fixed by an adhesive (not shown) or the like. .

FIG. 5 is a schematic diagram for explaining the structure when the PTC thermistor heating element is used in a warm air heater or a dryer. Reference numeral 6 is a PTC thermistor heating element, 7 is a fan motor, and 8 is a duct that serves as an air passage. Warm air can be easily obtained by allowing air to pass through the metal radiator 3 by the fan motor 7.

[0005]

However, the above-mentioned conventional configuration has the following problems. First, when the positive temperature coefficient thermistor heating element is used in a hot air heater,
When switching the operation of the heating capacity, it is required that hot air of a temperature that is not too hot and does not feel cold is blown from the entire heating element. Here, in the conventional configuration, a method of arranging a plurality of positive temperature coefficient thermistor heating elements in parallel in the ventilation direction to switch the operation of the heating capacity and energizing only the necessary positive temperature coefficient thermistor heating elements by switching the energization is a method. is there. However, in this case, there is a problem that the air blown from the non-energized positive temperature coefficient thermistor heating element becomes cool, and the warm air is not blown from the entire outlet of the warm air heater. There is also a method of switching the operation of the heating capacity by changing the amount of air blown by the fan motor, but if the amount of air blown is made smaller, the force of warm air is weak and the temperature is too hot.

Next, when the PTC thermistor heating element is used in a dryer such as a futon dryer or a clothes dryer, the temperature of warm air is important as well as the drying capacity. That is, for the drying of futons, clothing, and blankets that are vulnerable to heat, it is required to maintain the drying ability and prevent shrinkage due to high temperatures. Therefore, in the conventional configuration, there is a method of arranging a plurality of positive temperature coefficient thermistor heating elements in series with respect to the ventilation direction and controlling the temperature of the hot air by energizing only the necessary positive temperature coefficient thermistor heating elements by switching the energization. . However, in this case, a plurality of positive temperature coefficient thermistor heating elements are required, the simplification of the structure and the downsizing of the shape cannot be achieved, and air is difficult to pass because they are arranged in series in the ventilation direction, There is a problem that lint and cotton dust are easily clogged.

The present invention solves the above-mentioned problems of the prior art, can realize simplification of the structure and size of a heater, and can easily control the amount of heat generation and the temperature of warm air. It is an object of the present invention to provide a positive temperature coefficient thermistor heating element that can be used.

[0008]

In order to achieve this object, the PTC thermistor heating element of the present invention is provided with a PTC thermistor having electrodes provided on both sides and a through hole arranged on the electrode. A metal heat sink and a terminal electrically connected to the electrode directly or via the metal heat sink are provided, and at least one of the electrodes is divided into a plurality of parts.

[0009]

With this structure, while the air is passed through the metal radiator by the fan motor, the terminals led out from the plurality of divided electrodes in the ventilation direction are switched to be energized to obtain a plurality of positive characteristics. The same effect can be obtained by arranging the thermistor heating elements in series in the airflow direction, and warm air can be obtained from the entire PTC thermistor heating element, and the amount of heat generated by one PTC thermistor heating element can be increased. And the temperature of warm air can be easily controlled.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of a PTC thermistor heating element according to this embodiment, and FIG. 2 is a perspective view thereof. Figure 1,
In FIG. 2, 1 is a positive temperature coefficient thermistor, 2a, 2b, 2
Reference numeral c is an electrode made of aluminum or the like applied to both surfaces thereof by a thermal spraying method or the like. The electrode 2a is provided on the entire surface of one surface (back surface) of the positive temperature coefficient thermistor 1, and the electrode 2b,
2c is divided and given to the other surface (front surface). In this embodiment, two PTC thermistors 1 are used,
These are arranged so as to be in the same direction as the longitudinal direction of the electrodes 2a, 2b, 2c.

Reference numeral 3 denotes a metal radiator made of a metal having a high thermal conductivity such as aluminum. A large number of through holes 3a are opened to increase the surface area, and the amount of heat generated can be increased by ventilation. Then, the terminals 4a, 4b, 4c such as aluminum thin plates and the insulating sheet 5 such as alumina are sequentially stacked on both surfaces of the positive temperature coefficient thermistor 1 arranged on the same plane and are arranged between the pair of metal radiators 3. It is fixed while being pressed by an insulating adhesive (not shown) such as a silicon-based adhesive. Here, the positive temperature coefficient thermistor 1 is arranged so that the electrodes 2b and 2c are divided with respect to the ventilation direction that allows air to pass through the through holes 3a formed in the metal radiator 3. Further, the terminals 4a, 4b, 4c are directly abutted on the independent electrodes 2a, 2b, 2c, respectively, and are terminals for leading out to the outside.

In the PTC thermistor heating element constructed as described above, the air is passed through the metal radiator 3 and between the terminal 4a and either one of the terminals 4b or 4c, or the terminal 4a. By switching the energization so as to apply a voltage between both the terminals 4b and 4c, warm air can be obtained from the entire PTC thermistor heating element, and one PTC thermistor heating element itself can be obtained. Can easily control the amount of heat generation and the temperature of warm air. That is, the heat generation amount and the temperature of the warm air can be controlled to increase or decrease by the area ratio of the divided electrodes 2b and 2c.

Therefore, when the positive temperature coefficient thermistor heating element of the present embodiment is used in a hot air heater, the heating capacity can be switched by switching the energization by the terminals 4a, 4b, 4c of the positive temperature coefficient thermistor heating element. Since warm air is always blown from the entire surface of the positive temperature coefficient thermistor heating element, there is no partial blow of cold air, which makes it easy to control the amount of heat generated and the temperature of the hot air. It becomes possible to provide a heater. Also, when used in futon dryers and clothes dryers, it is easy to control the temperature of warm air, so it is necessary to prevent shrinkage of futons and clothes that are sensitive to heat due to high temperatures with complicated electronic control circuits. Instead, it can be easily performed by the PTC thermistor heating element.

The electrode 2 divided in this embodiment is used.
Although b and 2c are two, needless to say, the number of heat generations and the temperature of the warm air may be controlled more finely by further dividing. Further, in this embodiment, the terminal 4
Although a, 4b, and 4c are terminals for leading out from the independent electrodes 2a, 2b, and 2c, the metal heat radiator 3 is fixed so as to be electrically connected to the independent electrodes 2a, 2b, and 2c, and metal heat radiation is performed. It goes without saying that the body 3 may have a structure that also serves as a terminal.

[0015]

As described above, according to the present invention, a positive temperature coefficient thermistor having electrodes on both sides, a metal radiator provided with a through hole arranged on the electrodes, and a direct or indirect connection with the electrodes are provided. Since at least one of the electrodes is divided into a plurality of parts, it is possible to easily generate heat by switching the energization of the terminals without using a plurality of PTC thermistor heating elements as in the past. It is also possible to realize an excellent positive temperature coefficient thermistor heating element capable of controlling the temperature of hot air and simplifying the structure of a heater and reducing the size of the heater.

[Brief description of drawings]

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

FIG. 2 is a perspective view of the same positive temperature coefficient thermistor heating element.

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

FIG. 4 is an exploded perspective view of the PTC thermistor heating element.

FIG. 5 is a schematic configuration diagram illustrating a usage example of a PTC thermistor heating element.

[Explanation of symbols]

 1 Positive Characteristic Thermistor 2a, 2b, 2c Electrode 3 Metal Radiator 3a Through Hole 4a, 4b, 4c Terminal 5 Insulation Sheet

Claims (1)

[Claims] 1. A positive temperature coefficient thermistor having electrodes on both sides, a metal radiator provided with a through hole arranged on the electrode, and conductively connected to the electrode directly or through the metal radiator. A positive temperature coefficient thermistor heating element, comprising: a terminal, wherein at least one of the electrodes is divided into a plurality.