JPH043441Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a positive temperature coefficient thermistor device used for starting compressors, etc.

(b) Conventional technology Conventionally, in order to reduce motor loss in electric motors such as compressors, a positive temperature coefficient thermistor element is connected in series with the auxiliary winding, and when starting, a large current is passed through the auxiliary winding to start the motor. Some devices start the motor and cut off the current flowing to the auxiliary winding during operation. Such a positive temperature coefficient thermistor device is disclosed, for example, in Japanese Utility Model Publication No. 58-34722, and as shown in FIGS. 12 to 15, a case 3 made of an insulator is used.
0, and two external connection terminals 31 and 32 attached to the case so as to penetrate inside and outside the case.
and spring terminals 33 and 34 which are fixed to the inner part of each case 30 of the connection terminal and are arranged to face each other within the case, and which are elastically held between the two spring terminals. It is composed of a positive temperature coefficient thermistor element 35. The spring terminals 33 and 34 also include base parts 36 and 37 fixed to the connection terminals 31 and 32, and four tongue pieces 38 bent into a V-shape so as to face each other from the base parts.
39 is integrally formed with stainless steel plate material,
The width of each tongue piece is at the base 4 near the bases 36 and 37.
The dimensions are the same from 0, 41 to tips 42, 43.

(c) Problems to be solved by the invention Here, since the above-mentioned spring terminals 33 and 34 conductively press the positive temperature coefficient thermistor 35 and fix it in the case 30, stable electrical contact can be achieved. Not only is it required that the thermistor element 35 has an elastic force that firmly supports the thermistor, but it also needs to have a high thermal resistance in order to prevent the heat of the thermistor element 35 from being transmitted to the connection terminals as much as possible during compressor operation. be done. However, according to the above structure, the spring terminal 3
The tongue pieces 38 and 39 of No. 3 and 35 have base portions 40,
Since the dimensions from 41 to the tips 42 and 43 are uniform, if the width is made uniformly wider or the thickness is made thicker in order to increase the elastic force, the heat conduction of the terminal will improve and the Watt loss due to leakage current increases, and conversely, if the width dimensions of the tongues 38 and 39 are uniformly narrowed or the thicknesses are made thin in an attempt to suppress heat conduction as much as possible, the elastic force decreases and the thermistor element There was a problem in that it was not possible to stably hold the 35.

This design was developed in view of these points, and not only can the PTC thermistor element be firmly clamped, but also the heat transmitted from the thermistor element to the connection terminal during operation of a motor, etc. can be suppressed to a minimum, and there is less loss due to leakage current. The present invention aims to provide a positive temperature coefficient thermistor device.

(d) Measures to solve the problem This proposal consists of a case made of insulating material, at least two external connection terminals attached to the case so as to penetrate inside and outside the case, and one of these connection terminals. A spring terminal that is fixed to the inner part of each of the two terminals and arranged to face each other within the case, and a positive temperature coefficient thermistor element that is elastically held between the two spring terminals. In the spring terminal, the spring terminal is formed of a plate material whose width gradually becomes narrower from the root portion on the connection terminal side to the tip portion on the thermistor element side.

(e) Effect The positive temperature coefficient thermistor device of the present invention has the above-mentioned configuration, and the elastic force of the spring terminal is increased to some extent at the wide root and the portion where the width gradually becomes narrower from this root to press the thermistor element. By press-contacting the narrow tip to the thermistor element while increasing the force, it is possible to suppress the heat transmitted from the thermistor element to the connection terminal via the spring terminal, and to protect the PTC thermistor element from the case. In addition to being firmly supported within the motor, it is possible to reduce leakage current during operation of the motor, thereby reducing power loss.

(f) Examples Examples of the present invention will be described below based on the drawings.

Reference numeral 1 denotes a case consisting of an upper case 1a and a lower case 1b made of an insulating material (such as unsaturated polyester resin). Reference numerals 2 and 3 denote two external connection terminals that are detachably attached to the case 1 so as to pass through the inside and outside of the case 1, and tab terminals 2a and 3a for connection with an external electric circuit are provided at one end of the terminals. However, receptacles 2b and 3b for connection to a compressor terminal are integrally formed at the other end, and protrusions 2c and 3c for attaching spring terminals 4 and 5, which will be described later, are integrally formed in the center. 4 and 5 are protruding pieces 2 of the connection terminals 2 and 3;
These spring terminals are made of stainless steel and are fixed to the terminals c and 3c and are arranged so as to face each other within the case 1. As shown in FIGS. 5 to 7, this spring terminal has a base 4a fixed to the connection terminals 2 and 3,
5a, and a pair of terminal pieces 4b, 5b bent in a V-shape so as to face each other from this base, and each of the terminal pieces 4b, 5b has a V
It integrally includes two tongue pieces 4c, 5c forming a letter shape, and bridging pieces 4f, 5f which bridge the tips 4d, 5d of both tongue pieces and have ribs 4e, 5e in the bridging direction. are doing. The tongues 4c, 5c are formed to become gradually narrower from the root portions 4g, 5g near the base portions 4a, 5a toward the tip portions 4d, 5d. Reference numeral 6 denotes a disk-shaped positive temperature coefficient thermistor element whose end surfaces are held between the spring terminals 4 and 5. This element is pressed from both sides by tips 4d, 5d of tongues 4c, 5c formed on the spring terminals 4, 5. Further, the element 6 is connected to the upper case 1a.
Support plate 8 made of mica material inserted into groove 7 of
is inserted into the hole 9 and positioned.

In the positive temperature coefficient thermistor device configured in this way, the tongue pieces 4c, 5c of the spring terminals 4, 5, respectively.
are the bases 4a, 5a fixed to the connection terminals 2, 3
The thermistor element 6 is connected from the nearby roots 4g and 5g.
The tongue pieces 4c, 5 are formed so as to become gradually narrower toward the tip portions 4d, 5d that press the tongues 4c, 5.
Since the elastic force of c can be increased to increase the pressure contact force to the thermistor element 6, and the contact area between the tongue piece and the thermistor element 6 is reduced,
During operation of the electric motor, the heat transmitted from the thermistor element 6 to the connection terminals 2 and 3 via the spring terminal can be suppressed to a small extent, and leakage current can be reduced to reduce power loss.

Further, FIGS. 8 to 11 show another embodiment in which the shape of the spring terminals 12, 13 fixed to the external connection terminals 10, 11 is bent into a V-shape from the bases 14, 15. four tongue pieces 16,
17, and each tongue piece is formed with a respective base 1.
From the base parts 18, 19 near 4, 15 to the tip part 2
It is formed so that the width becomes gradually narrower toward 0 and 21, and this also produces the same effect as the embodiment shown in FIG.

(g) Effects of the invention As described above, the present invention includes a case made of an insulating material, at least two external connection terminals attached to the case so as to penetrate inside and outside the case,
Two of the connection terminals have a spring terminal fixed to the inner part of the case and arranged to face each other within the case, and a positive characteristic that is elastically held between the two spring terminals. In the thermistor element, the spring terminal is formed of a plate material whose width gradually becomes narrower from the root part on the connection terminal side to the tip part on the thermistor element side, so that the elastic force of the spring terminal is ensured. While increasing the pressure contact force to the thermistor element, the heat transmitted from the thermistor element to the connection terminal can be suppressed, and the thermistor element is firmly supported within the case, improving reliability and improving reliability during motor operation, etc. It is possible to reduce leakage current and reduce power loss.

[Brief explanation of the drawing]

1 to 7 show an embodiment of the present invention, FIGS. 1 and 2 are a plan view and a side view of a PTC thermistor device, and FIG. 3 is a PTC thermistor device shown in FIG. 4 is a longitudinal sectional view of the PTC thermistor device, FIGS. 5 to 7 are front and side views of the connecting terminal, and FIGS. 8 to 11 show other embodiments. Fig. 8 is a longitudinal sectional view of a positive temperature coefficient thermistor device, Figs. 9 to 11 are front and side views of a connecting terminal, Figs. 12 to 15 are conventional examples, and Fig. 12 is a positive temperature coefficient thermistor device. FIG. 13 is a longitudinal sectional view of the PTC thermistor device, and FIGS. 14 and 15 are front views of the connecting terminal. 1... Case, 1a... Upper case, 1b... Lower case, 2, 3... Connection terminal, 4, 5... Spring terminal, 4c, 5c... Tongue piece, 4d, 5d... Tip, 4g , 5g...root portion, 6...positive temperature coefficient thermistor element.

Claims (1)

[Scope of utility model registration request] a case made of an insulating material; at least two external connection terminals attached to the case so as to pass through the inside and outside of the case; and two of the connection terminals each fixed to the inner part of the case; A device consisting of a spring terminal arranged to face each other within the case, and a positive temperature coefficient thermistor element elastically held by both the spring terminals,
A positive temperature coefficient thermistor device, wherein the spring terminal is formed of a plate material whose width gradually becomes narrower from a root portion on the connection terminal side to a tip portion on the thermistor element side.