JPS6035202Y2 - Electrode plate for positive temperature characteristic thermistor devices, etc. - Google Patents

Description

[Detailed description of the invention] The present invention relates to an element holding structure for a positive temperature coefficient thermistor device, etc., which has a built-in positive temperature coefficient thermistor and is connected to a motor terminal and used as a non-contact starter for refrigerators, etc. One of the objectives is to minimize the increase in power consumption, which is the biggest drawback compared to starters.

Figure 1 shows the equivalent circuit of a general capacitor-start motor. 1 is the main winding, 2 is the starting winding, 3 is the positive temperature characteristic thermistor, and 4 is the starting capacitor. , B, and C are motor terminals that are not shown in the figure but are led out to the outside of the motor case.

The present invention relates to a positive temperature characteristic thermistor device connected within terminals A, B, and C and to terminals B and C.

That is, when the motor is started, a current flows to the starting winding 2 side, the motor starts easily, and the positive temperature characteristic thermistor 3 suddenly becomes high resistance due to the current, and the main winding 1
Current flows through the circuit, and the motor enters rated operation.

Therefore, one conventional example will be explained with reference to FIGS. 2 and 3. Reference numerals 5 and 5' are spring terminals connected to the motor terminals,
These spring terminals 5 and 5' are the motor terminals B and 5', respectively.
6 and 6' are external wiring connection terminals, which are connected to the external wiring cord receptacle.

Reference numerals 7 and 7' denote electrode plates that sandwich the positive temperature characteristic thermistor 8, and the positive temperature characteristic thermistor 8 is fixed by the electrode plates 7 and 7'.

The spring terminal 5' and the electrode plate 7 are welded at their joints 9 by spot welding, etc., and the spring terminal 5 and the external wiring terminal 6 are welded at their joints 10 by spot welding, etc. The electrode plate 7' and the external wiring terminal 6' are connected at their respective joints 11 in the same manner.
Welded by spot welding, the electrode plates 7, 7',
Although the spring terminal 5.5', external wiring terminal 6.6', and positive temperature coefficient thermistor 8 are not shown in the figure, they are each covered and housed in an insulating case configured to be housed in a predetermined position. .

In the positive temperature characteristic thermistor device having the above configuration, conventionally, the cross-sectional view of the holding part E' of the positive temperature characteristic thermistor 8 is as shown in FIG. Plating layer 13 with low contact resistance
A positive temperature characteristic thermistor 8 was held between the electrode plates 7° 7'.

This is because when the positive temperature coefficient thermistor 8 has a high resistance, heat is transferred from the positive temperature coefficient thermistor 8 through the electrode plates 7, 7' to the spring terminals 5, 5' or the terminals 6, 6', and to the outside. The purpose was to reduce the power consumption in the positive temperature coefficient thermistor 8' by increasing the amount of heat escaping to the positive temperature coefficient thermistor 8 as much as possible and reducing the contact resistance at the point of contact with the positive temperature coefficient thermistor 8.

However, since the electrode plates 7 and 7' configured in this manner require plating, a plating layer is formed at unnecessary locations other than the contact area with the PTC thermistor 8, so a noble metal such as silver is used as the plating layer. In this case, the cost will increase.

In addition, when the electrode base material 12 is made of stainless steel, plating is difficult to adhere to compared to copper-based materials, so there are material and cost issues such as a considerable number of man-hours required for plating pretreatment, and ease of use may be affected. There was a drawback.

Therefore, conventionally, although not shown in the figure, the electrode plate was made of beryllium copper or phosphor bronze, but since these copper-based materials have high thermal conductivity, it is difficult to connect the positive temperature coefficient thermistor 8 to the electrode plate through the electrode plate. There is a drawback that a large amount of heat escapes to the outside, and therefore, the amount of self-heating in the positive temperature coefficient thermistor increases, resulting in high power consumption.

Therefore, the present invention solves the above-mentioned drawbacks, makes it easier to configure the electrode plate, and reduces power consumption.
An embodiment of the present invention will be explained with reference to FIG.

A coating layer 15 made of silver or the like is provided only on the contact portion side with the positive temperature coefficient thermistor 8 of the electrode plate base material 14 holding the positive temperature coefficient thermistor 8.

This coating layer 15 is obtained by coating an electrode material with low contact resistance such as silver in the form of a paste and then baking it at a high temperature of about 580°C.

The electrode plate base material 14 is made of a metal material having a lower thermal conductivity than copper-based materials such as stainless steel.

In the electrode plates 16 and 16' configured as described above, even if the electrode plate base material 14 is made of a material such as stainless steel, which has poor throwing power such as plating, it can be easily coated and baked, that is, the electrode plate The material selection for the base material 14 is wide-ranging, and the coating layer 15 can be formed only on the contact side with the positive temperature coefficient thermistor 8 without going through a plating process, and the electrode material can be a noble metal such as silver or gold. When forming the coating layer 15, the amount of material used is small, so compared to conventional plating methods, it is possible to reduce the number of holes, save materials, and reduce costs.In addition, it reduces power consumption. It has a measurable effect.

As is clear from the above description, the present invention is an electrode plate for a positive temperature coefficient thermistor device, etc., which is characterized by coating and baking a metal material with low contact resistance on a metal material with a lower thermal conductivity than a copper-based material. Yes, it has the following effects.

(a) Even if the electrode plate is made of a metal such as stainless steel that has poor throwing power due to plating, etc., the electrode material such as silver can be easily coated and baked, so that the number of cracks can be reduced compared to the conventional method.

(b) Material selection for the electrode plate base material can be easily made.

Furthermore, when this electrode plate is used in a positive temperature coefficient thermistor, etc., the amount of heat escaping from the positive temperature coefficient thermistor to the outside is smaller than that of conventional copper-based materials, and the power consumption of the positive temperature coefficient thermistor can be significantly reduced.

(C) The electrode material can be applied on the electrode plate, for example, on the contact side with the positive temperature coefficient thermistor, or only on the contact part, so when using noble metal electrode materials such as silver or gold, the material used can be minimized. It is possible to reduce costs by keeping costs down, and it has great practical effects, such as being able to be carried out with simpler equipment than the plating method.

[Brief explanation of the drawing]

Fig. 1 is an equivalent circuit diagram for starting a motor, Fig. 2 is a perspective view of a positive temperature coefficient thermistor holding part showing an example of a conventional positive temperature coefficient thermistor device with a spring terminal, and Fig. 3 is a diagram showing E' line in Fig. 2. FIG. 4 is a sectional view corresponding to FIG. 3 showing an embodiment of the present invention. 14... Electrode plate base material, 15... Coating layer.

Claims (1)

[Scope of utility model registration request] An electrode plate for a positive temperature characteristic thermistor device, etc., characterized in that a metal material with low contact resistance is coated and baked on a metal material with a thermal conductivity lower than that of a copper-based material.