JPH08264303A - Positive characteristic thermistor device - Google Patents

Abstract

PURPOSE: To provide a positive characteristic thermistor device with which the temperature distribution of the outer circumference, where a through hole is formed, of a case is made small and an insecticide, etc., can be evaporated uniformly from the suction shaft. CONSTITUTION: The subject positive characteristic thermistor device is composed of a case 11, having a cylindrical through hole 17 and a recessed part 18, a flat plate type positive characteristic thermistor element 14, a pair of power supply terminals, a pipe 23 and a cover 12. The pipe 23 is arranged in the through hole 17, and the pair of power supply terminals consist of a power supply terminal, having almost flat plate part on one side, and a power supply part having an elastic connection part 26a on the other side. One of power supply terminals, the positive characteristic thermistor element 14 and other power supply terminal are housed in the recessed part 18 of the case 11 the lead-out part of the pair of power supply terminals is led out from the side part of the recessed part 18 of the case 11, and the aperture part of the recessed part 18 of the case 11 is covered by a cover 12.

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 device for use in insecticides such as liquid type electronic mosquito traps, aroma machines, etc., and particularly to effective and even distribution of heat generated from positive temperature coefficient thermistor elements. The present invention relates to a positive temperature coefficient thermistor device.

[0002]

2. Description of the Related Art Conventional PTC thermistor devices include those shown in FIGS. The PTC thermistor device of this conventional example includes a case 11, a lid 12, a plate-shaped PTC thermistor element 14 having electrodes 14a and 14b formed on both main surfaces, and a pair of power supply terminals 15 and 16. Composed.

The case 11 is made of an insulating ceramic material such as porcelain, and has a cylindrical through hole 17 and the through hole 1.
7, the positive temperature coefficient thermistor element 1 via the partition wall 11a.
4 and a pair of power supply terminals 15 and 16 and a recess 18 having an opening that can be accommodated.

The lid 12 covers the opening of the recess 18 and has notches 12a and 12b formed at the end of the lid 12, and the lead portions 15b and 16b of the pair of power supply terminals 15 and 16 are connected to each other. Can be pulled out upwards.

One of the pair of power supply terminals 15 and 16 is a flat terminal and the other is a spring terminal. In this case, one of the power supply terminals 15 is a flat terminal made of metal, and one end of the power supply terminal 15 has a substantially flat plate portion 15a that comes into contact with the electrode 14a of the positive temperature coefficient thermistor element 14, and the other end has a case 11a. And a pull-out portion 15b that is pulled out above. The other power supply terminal 16 is a spring terminal made of elastic metal, and has a resilient contact portion 16b that is resiliently in contact with the electrode 14b of the positive temperature coefficient thermistor element 14 at one end side and an upper side of the case 11 at the other end side. It is composed of a drawer portion 16b that is pulled out.

In the positive temperature coefficient thermistor device composed of such constituent members, one power supply terminal 15, the positive temperature coefficient thermistor element 14, and the other power supply terminal 16 are housed in the recess 18 in this order from the partition wall 11a side, and a pair of power supply terminals 15 are accommodated. , 16 are electrically connected to the electrodes 14a, 14b of the PTC thermistor element 14, respectively, and the opening of the recess 18 is covered with the lid 12. At this time, the lead-out portions 15b and 16b of the pair of power supply terminals 15 and 16 are provided with the notches 12a of the lid 12 and
It is pulled out to the upper outside via 2b.

In the positive temperature coefficient thermistor device having such a structure, the positive temperature coefficient thermistor element 14 generates constant temperature heat by energizing the pair of power feeding terminals 15 and 16, and the heat is generated in the flat plate portion 15a of the one power feeding terminal 15 and the case 11. Is conducted to the through hole 17 through the partition wall 11a.

[0008]

However, the above-mentioned conventional positive temperature coefficient thermistor device has the following problems. That is, the temperature distribution of the outer peripheral portion of the case 11 forming the through hole 17 greatly varies, that is, at the point P closest to the main surface of the positive temperature coefficient thermistor element 14, the electrode that is one main surface of the positive temperature coefficient thermistor element 14. 14a and partition wall 11
Since a is in surface contact with the flat plate portion 15a of one power supply terminal 15 and the heat transfer path is short, the heat from the positive temperature coefficient thermistor element 14 is efficiently transferred and reaches the highest temperature.

On the other hand, at the point Q farthest from the positive temperature coefficient thermistor element 14, the heat transfer path is the longest and heat is dissipated in the middle of the heat transfer path, so that the temperature becomes the lowest, and the points P and Q have the same temperature. The temperature difference becomes large. For this reason, the wicking rod 19 inserted into the through hole 17 could not uniformly and efficiently volatilize the insecticidal liquid or the like.

Further, the plate-shaped positive temperature coefficient thermistor element 14 is accommodated vertically in the height direction of the case 11, and the lead portions 15b, 1 of the pair of power supply terminals 15, 16 are provided.
In order to pull out 6b to the outside of the upper side of the case 11, the height of the entire positive temperature coefficient thermistor device is increased, and there is a limit to the reduction in size and height of the liquid type electronic mosquito trap.

Therefore, the present invention has been made in order to solve the above-mentioned problems, and the temperature distribution of the outer peripheral portion forming the through hole of the case is made smaller so that the suction core rod inserted into the through hole can be used. An object of the present invention is to provide a positive temperature coefficient thermistor device capable of uniformly and efficiently evaporating an insecticidal liquid and the like.

[0012]

In order to achieve the above object, in a positive temperature coefficient thermistor device of the present invention, a case having a cylindrical through hole and a recess formed in the vicinity of the through hole, and both main surfaces are provided. A plate-shaped positive temperature coefficient thermistor element having an electrode formed on, a pair of power supply terminals, a metal pipe, and a lid, the pipe being disposed inside the through hole, The power supply terminal of one is composed of a power supply terminal having a substantially flat plate portion and the other is a power supply terminal having an elastic contact portion, and the one power supply terminal, the positive temperature coefficient thermistor element, and the other power supply terminal are provided in the recess of the case. Terminals are accommodated, the electrodes on both main surfaces of the positive temperature coefficient thermistor element and the pair of power supply terminals are electrically connected to each other, and the lead portions of the pair of power feed terminals are pulled out from the side portions of the recesses of the case, The lid Accordingly, characterized in that the recess opening of the case is covered.

The lid is made of a resin having a low thermal conductivity, has a through hole of substantially the same shape corresponding to the through hole of the case, and has a locking piece formed therein. An engaging portion that engages with the locking piece is formed on the outer wall surface of the recess, the pipe is inserted into the through hole of the lid and the through hole of the case, and the engagement formed on the lid is performed. The lid body is fixed to the case by engaging a stop piece and an engaging portion formed on the case.

Further, the lid is characterized in that it has a mounting base at its end. Furthermore, the case is made of alumina porcelain having a purity of 75% or more. Furthermore, at least one of the pair of power supply terminals is provided with a narrow width portion, and the narrow width portion is located in the recess of the case and does not contact the inner wall surface or the bottom surface of the recess. To do.

[0015]

According to the present invention, with the above-described structure, the heat from the positive temperature coefficient thermistor element is transferred from its main surface to the entire outer peripheral wall of the through hole of the case through one power supply terminal and the bottom surface of the case. The heat transfer path to the P point of the case becomes longer, and the difference is smaller than the heat transfer path to the Q point of the case.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail below with reference to FIG. However, the same parts as those of the above-described conventional example and the parts having the same functions are designated by the same reference numerals, and detailed description thereof will be omitted.

This positive temperature coefficient thermistor device has a case 11
A lid 12, a metal pipe 23, a plate-shaped positive temperature coefficient thermistor element 14, and a pair of power supply terminals 25 and 26.

The case 11 is made of, for example, an insulative ceramic material such as zirconia porcelain, and has a through hole 17 into which the pipe 23 can be press-fitted, and a positive temperature coefficient thermistor element 14 via a partition wall 11a near the through hole 17. And a recess 18 having an opening capable of accommodating the pair of power supply terminals 25, 26.
Is formed, and a protrusion 11b that restricts the movement of the positive temperature coefficient thermistor element 14 and the other power supply terminal 26 is provided on the sidewall of the recess 18. In addition, a lead-out portion 25 of the pair of power supply terminals 25 and 26 is provided on the upper side wall of the case 11.
Notches 11c and 1 that can be used to pull out b and 26b
1d is formed.

The lid 12 is made of a resin having a low thermal conductivity such as PPS (polypropylene sulfite), phenol and nylon resin, and can cover the opening of the recess 18 of the case 11.

The pipe 23 is made of, for example, aluminum having good thermal conductivity, has a tubular shape, and is fitted into the through hole 17 of the case 11.

One of the pair of power supply terminals 25 and 26 is a flat terminal and the other is a spring terminal. In this case, one power supply terminal 25 is a flat terminal made of a metal such as SUS (stainless steel), and has a substantially flat plate-like shape which is in contact with the electrode 14a, which is one main surface of the positive temperature coefficient thermistor element 14, at one end thereof. It is composed of a flat plate portion 25a and a lead-out portion 25b that is pulled out to the side portion of the case 11 on the other end side, and a notch or slit in the width direction of the lead-out portion 25b between the flat plate portion 25a and the lead-out portion 25b. Narrow portion 25 formed by
c is provided. The other power supply terminal 26 is a spring terminal made of a metal having elasticity such as SUS or phosphor bronze, and one end thereof has the electrode 1 of the positive temperature coefficient thermistor element 14.
4b and the elastic contact portion 26b, and the case 11 on the other end side.
And a pull-out portion 26b that is pulled out to the side of the.

In the positive temperature coefficient thermistor device composed of such constituent members, the pipe 23 is fitted into the through hole 17 of the case 11 with almost no gap from the inner wall thereof, and one of the power feeds is sequentially inserted into the recess 18 from the bottom surface 11e. Terminal 25, positive temperature coefficient thermistor element 14, other power supply terminal 26
And a pair of power supply terminals 25 and 26 are electrically connected to the electrodes 14a and 14b of the positive temperature coefficient thermistor element 14, respectively, and the opening of the recess 18 is covered with the lid 12. The case 11 and the lid 12 are, for example,
It is joined using a heat-resistant silicone adhesive or the like. At this time, the positive temperature coefficient thermistor element 14 and the other power supply terminal 26
The movement of one of the power supply terminals 25 in the direction of the narrow portion 25c is restricted by the protrusion 11b provided in the recess 18,
Insulation from the narrow portion 25c of one power supply terminal 25 is maintained. In addition, the lead-out portions 25b and 26b of the pair of power supply terminals 25 and 26 are provided in the notch 1 of the case 11.
It is pulled out laterally from the side wall of the recess 18 via 1c and 11d. Further, the narrow width portion 25c provided on one power supply terminal 25 is bent from the flat plate portion 25a, and is arranged at a position where it does not contact the inner wall surface of the recess 18 and the bottom surface 11e.

In the positive temperature coefficient thermistor device having such a structure, the positive temperature coefficient thermistor element 14 heats up at a constant temperature when the pair of power feeding terminals 25 and 26 are energized, and the heat is generated in the flat plate portion 25a of one power feeding terminal 25 and the case. Bottom of 11
It is conducted from the through hole 17 of the case 11 to the pipe 23 via e. At this time, the electrode 14a, which is the lower main surface of the positive temperature coefficient thermistor element 14, makes surface contact with the bottom surface 11e of the case 11 via the flat plate portion 25a, and heat is efficiently conducted to the case 11. Therefore, the heat from the positive temperature coefficient thermistor element 14 passes through the bottom surface 11e of the case 11 through the through hole 17
Since it is conducted to the outer peripheral wall that forms the heat transfer path, the difference between the heat transfer paths to the points P and Q becomes small, and the temperature difference also becomes small.
Therefore, the heat from the positive temperature coefficient thermistor element 14 is efficiently conducted to the pipe 23, and the pipe 23 having good heat conduction makes the temperature distribution of the pipe 23 more uniform.

Further, since the recess 18 of the case 11 is simply sealed by the lid 12, the positive temperature coefficient thermistor element 14 is provided.
It is possible to protect from harmful substances, such as vapor of insecticidal liquid, which may interfere with the contact points between the pair of power supply terminals 25 and 26.

In the present embodiment, the narrow width portion 25c is provided on one power supply terminal 25, but it may be provided on the other power supply terminal 26.

Next, a second embodiment of the present invention will be described in detail with reference to FIG. However, the same parts and the same functional parts as those in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted. This embodiment is the same as the above-mentioned first.
Case 31, lid 32 and pipe 3 as compared with the embodiment
3 is different.

In other words, this PTC thermistor device has a case 31, a lid 32, a metal pipe 33, a plate-shaped PTC thermistor element 14, a pair of feeding terminals 25,
And 26.

The case 31 is the case 11 of the first embodiment.
Further, an engaging portion 31f formed of a protrusion or the like is formed outside the side wall and located between the notches 11c and 11d.

The lid 32 has one end side of the lid 12 of the first embodiment extended to form a through hole 32a at a position corresponding to the through hole 17 of the case 31, and the other end of the case 32 to an engaging portion of the case 31. A locking piece 32b that engages with 31f is provided, and further, a mounting base 32c that projects from the side portion of the case 31 when the opening of the case 31 is covered is provided on the side portion. A mounting notch 32d such as a through hole or a female screw is formed in the base 32c.

The pipe 33 is made of a metal such as aluminum having a high thermal conductivity, and has a grommet shape with a flange 33a formed at one end.

In the positive temperature coefficient thermistor device composed of such constituent members, one feeding terminal 25, the positive temperature coefficient thermistor element 14 and the other power feeding terminal 26 are housed in the recess 18 of the case 31 in order from the bottom surface 11e, and the opening surface of the recess 18 is accommodated. Is covered with a lid 32. The case 31 and the lid 32 are joined together at two locations as follows. In other words, one side is provided with an engaging portion 31f provided on the case 31, and a lid 32 is provided.
The locking piece 32b provided on the above is locked. On the other hand, the through hole 17 of the case 31 and the through hole 32 of the lid 32 are overlapped to form one apparent through hole, and the pipe 33 is inserted into the apparent one through hole from the lower side. The upper end of the pipe 33 on the side opposite to is crimped. At this time, the lead-out portions 25b and 26b of the pair of power supply terminals 25 and 26 are attached to the case 3
It is pulled out laterally from the side wall through the one notch 11c, 11d. Further, the mounting base 32c is the case 3
1 project from the side. The mounting base 32c itself is clamped, or the notch 3 provided in the base 32c.
The positive temperature coefficient thermistor device can be easily attached and fixed to the liquid type electronic mosquito catcher main body or the like by screwing or the like using 2d.

The mounting base 32c and the notch 3
The shape of 2d and the mounting method are not limited to the above-described embodiment.

Next, the configuration of the first embodiment described above will be described with reference to FIG.
A third embodiment in which the inner lid 40 shown in FIG.
It should be noted that the figure showing the positive temperature coefficient thermistor device is omitted by referring to FIG.

That is, this PTC thermistor device includes a case 11, a lid 12, a metal pipe 23, a plate-shaped PTC thermistor element 14, a pair of power supply terminals 25,
26 and an inner lid 40.

The inner lid 40 is made of mica or the like, which has a lower thermal conductivity than the case 11 and is a nonflammable insulating plate.
Is provided between the lid 12 and the lid 12, and the recess 18 of the case 11 is provided.
To cover the opening. Therefore, the heat conduction from the positive temperature coefficient thermistor element 14 to the lid 12 is via the inner lid 40, and the heat conduction to the lid 12 becomes poor. That is, the lid 12 is protected from the heat generated by the positive temperature coefficient thermistor element 14 and can prevent wasteful heat dissipation, and the heat from the positive temperature coefficient thermistor element 14 is passed through the bottom surface 11e of the case 11 through the through hole. Can be efficiently communicated to 17. Since the case 11 and the inner lid 40, which are nonflammable insulators, surround the positive temperature coefficient thermistor element 14, the flame retardancy of the positive temperature coefficient thermistor device is increased regardless of the material of the lid 12.

The case 11 and the inner lid 40 can be adhered to each other with a heat-resistant adhesive or the like to enhance the airtightness of the recess 18.

Further, it is needless to say that the inner lid 40 shown in FIG. 3 can be added to the structure of the second embodiment as in the case of the third embodiment.

Furthermore, the cases 11 and 31 shown in FIGS. 1 and 2 have been described by taking an insulator such as porcelain as an example of the material, but the purity is higher than that of the case and suitable for powder formability. More preferably, it is composed of 75% or more alumina porcelain.

Furthermore, in the above embodiment, the recess 18
Although the example in which one power supply terminal 25 is arranged on the bottom surface 11e side of the above is shown, even if the other power supply terminal 26 is arranged on the bottom surface 11e side, the heat generated from the positive temperature coefficient thermistor element 14 is generated in the case 11 , 1 to the case 31, so that the case 1
The temperature difference between points P and Q of points 1 and 31 is small, which is effective for the problem of the present invention.

[0040]

As described above, the positive temperature coefficient thermistor device according to the present invention has the following effects.

1. The heat transfer path from the PTC thermistor element that has generated heat is one of the power supply terminals, the bottom surface of the case, the outer peripheral wall of the through hole, and the pipe. From the PTC thermistor element to the P point and Q point of the case, which is the outer peripheral portion of the pipe. Since the difference in the heat transfer path is small, the difference in the temperature distribution of the pipe can be small. Further, since the main surface of the positive temperature coefficient thermistor element is in surface contact with the bottom surface of the case via the flat plate portion of the one power supply terminal, heat is efficiently conducted. Furthermore, since the positive temperature coefficient thermistor element and the pair of power feeding terminals are accommodated horizontally in the recess of the case, and the lead-out portions of the pair of power feeding terminals are pulled out laterally from the side portions of the case, the positive temperature coefficient thermistor device The height can be reduced, and it is possible to cope with the reduction in size and height. Further, since one power supply terminal, the positive temperature coefficient thermistor element, the other power supply terminal and the lid can be housed in the concave portion of the case in order, the positive temperature coefficient thermistor element and the bottom surface of the case can be easily and surely brought into surface contact with each other. Can be made. Furthermore, if the PTC thermistor element is electrically damaged due to some abnormality, the PTC thermistor element may make surface contact with the through-hole of the case even if the bottom surface of the case that is in surface contact is destroyed by the impact. Since it is not done, the outer peripheral wall of the case through hole is not destroyed. Therefore,
It is safe because no current flows through the pipe, which is the metal of the non-charging part.

2. By penetrating the case and the lid with respective through holes, inserting the pipe into the through hole and caulking, and engaging the engaging portion and the locking piece provided on the case and the lid with each other, It can be fixed easily and firmly. Further, since the case and the engaging portion provided on the lid and the locking piece are located between the lead-out portions of the pair of power supply terminals drawn out from the case, the withstand voltage characteristic is improved. Furthermore, because the lid is made of resin with poor heat conduction,
The heat transferred from the positive temperature coefficient thermistor element to the case is efficiently transferred to the case without being transferred to the lid body. Also, since the positive temperature coefficient thermistor device is attached to the body of the liquid electronic mosquito trap via the base of the lid whose temperature is lower than that of the case, it is possible to lower the heat resistant temperature of the liquid electronic mosquito trap main body, and The safety and reliability of the electronic mosquito trap will be improved.

3. The PTC thermistor device can be easily fixed to the liquid type electronic mosquito catcher body or the like by the base and the notch provided at the end of the lid.

4. Alumina porcelain has a higher thermal conductivity than zirconia porcelain used for structural purposes, etc., so that heat from the PTC thermistor element can be efficiently conducted to the pipe.

5. The narrow portion provided on one of the power supply terminals functions as a fuse, and when the overcurrent flows through the PTC thermistor element, the narrow portion is melted to protect the PTC thermistor device from overcurrent. be able to.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a positive temperature coefficient thermistor device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of a positive temperature coefficient thermistor device according to a second embodiment of the present invention.

FIG. 3 is a perspective view of an inner lid used in a third embodiment according to the present invention.

FIG. 4 is a perspective view of a conventional example.

5 is a cross-sectional view taken along the plane A of FIG.

[Explanation of symbols]

 11, 31 Case 11e Bottom surface 12,32 Lid body 14 Positive temperature coefficient thermistor element 14a, 14b Electrode 17 Through hole 18 Recessed portion 23, 33 Pipe 25 One feeding terminal 25a Flat plate portion 25b Drawer portion 25c Narrow portion 26 Other feeding terminal 26a Elastic contact part 26b Drawout part 31f Engagement part 32b Locking piece 32c Base 40 40 Inner lid

[Procedure amendment]

[Submission date] January 22, 1996

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

One of the pair of power supply terminals 15 and 16 is a flat terminal and the other is a spring terminal. In this case, one of the power supply terminals 15 is a flat terminal made of metal, and one end of the power supply terminal 15 has a substantially flat plate portion 15a that comes into contact with the electrode 14a of the positive temperature coefficient thermistor element 14, and the other end has a case 11a. And a pull-out portion 15b that is pulled out above. The other power supply terminal 16 a spring terminal consisting of a metal having elasticity, and elastic contact portions 16 a elastically contacts thereon at one end electrode 14b of the PTC thermistor element 14, the upper and the other end side case 11 It is composed of a pull-out portion 16b that is pulled out.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

One of the pair of power supply terminals 25 and 26 is a flat terminal and the other is a spring terminal. In this case, one power supply terminal 25 is a flat terminal made of a metal such as SUS (stainless steel), and has a substantially flat plate-like shape which is in contact with the electrode 14a, which is one main surface of the positive temperature coefficient thermistor element 14, at one end thereof. It is composed of a flat plate portion 25a and a lead-out portion 25b that is pulled out to the side portion of the case 11 on the other end side, and a notch or slit in the width direction of the lead-out portion 25b between the flat plate portion 25a and the lead-out portion 25b. Narrow portion 25 formed by
c is provided. The other power supply terminal 26 is a spring terminal made of a metal having elasticity such as SUS or phosphor bronze, and one end thereof has the electrode 1 of the positive temperature coefficient thermistor element 14.
4b and a case 11 on the other end side.
And a pull-out portion 26b that is pulled out to the side of the.

Claims (5)

[Claims] 1. A case having a cylindrical through hole and a recess formed in the vicinity of the through hole, a plate-shaped positive temperature coefficient thermistor element having electrodes formed on both main surfaces thereof, and a pair of power supply terminals.
A metal pipe and a lid, the pipe is disposed inside the through hole, and one of the pair of power supply terminals has a substantially flat plate portion and the other has a resilient contact portion. A power supply terminal having, wherein the one power supply terminal, the PTC thermistor element and the other power supply terminal are housed in the recess of the case, the electrodes on both main surfaces of the PTC thermistor element and the pair of power supply terminals. The positive characteristic is characterized in that the terminals are electrically connected to each other, the lead-out portions of the pair of power supply terminals are drawn out from the side portions of the recess of the case, and the opening of the recess of the case is covered by the lid. Thermistor device. 2. The lid body is made of a resin having a low thermal conductivity, has a through hole of substantially the same shape corresponding to the through hole of the case, and has a locking piece formed therein. An engagement portion that engages with the locking piece is formed on the outer wall surface of the recess, and the pipe is inserted into the through hole of the lid body and the through hole of the case, and an engagement portion formed on the lid body. The positive temperature coefficient thermistor device according to claim 1, wherein the lid is fixed to the case by engaging a stop piece and an engaging portion formed on the case. 3. The positive temperature coefficient thermistor device according to claim 1, wherein the lid has a mounting base at an end thereof. 4. The positive temperature coefficient thermistor device according to claim 1, wherein the case is made of alumina porcelain having a purity of 75% or more. 5. A narrow portion is provided on at least one of the pair of feeding terminals, and the narrow portion is located in the recess of the case and does not come into contact with the inner wall surface or the bottom surface of the recess. The positive temperature coefficient thermistor device according to any one of claims 1 to 4, which is characterized in that.