JPH04206288A - Positive characteristic thermistor device - Google Patents

Abstract

PURPOSE:To obtain optimum exothermic temperature distribution by housing a pair of terminal electrodes and one positive characteristic thermistor element in an element housing part of an insulation case, covering an under surface opening with an insulation sheet, and making the upper side surface and the circumferential side surface of a through hole in the insulation case an exothermic part for heating. CONSTITUTION:An element housing part 3 opened on the under surface is provided in position leaned to one side from the center of an insulation case 1 having excellent heat conductivity and a through hole 2 vertically passing through is formed in position leaned to the other side from the center of the insulation case 1. A pair of terminal electrodes 8, 11 and one positive characteristic thermistor element 5 are housed in the element housing part 3, and an under surface opening of the element housing part 3 is covered with an insulation sheet. The upper side surface 19 and the circumferential side surface of the through hole 2 in the insulation case 1 are then made to form an exothermic part for heating. With this constitution, temperature distribution of the exothermic part can be equalized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a positive temperature coefficient thermistor device. Specifically, the present invention relates to a positive temperature coefficient thermistor device that can be used in both liquid type and mat type electric mosquito repellents.

[Prior Art] What is shown in FIGS. 9 and 10 is a conventional positive temperature coefficient thermistor device used in a liquid-type electric mosquito repellent, and what is shown in FIGS. 11 and 12 is a matte thermistor device. This is a positive temperature coefficient thermistor device used in electric mosquito repellents.

First, the positive temperature coefficient thermistor device 60 used in the liquid method will be explained. As shown in FIG. 9, this has a heating cylinder part 51 erected in the center, and leads are placed in an annular groove part 62 formed over the entire circumference of the cylinder part 51 of an insulating case 52 with an open top surface. Annular electrode plate 54 with portion 53
A ring-shaped positive characteristic (hereinafter abbreviated as PTC) thermistor element 61 with electrodes formed on both sides was delivered on the annular electrode plate 54, and a lead portion 55 was further placed on the PTC thermistor element 61. The annular electrode plate 56 with
An annular insulating sheet 57 is stacked on the upper surface of the insulating case 52. After that, a metal eyelet 5θ made of aluminum or the like is inserted into the through hole 58 of the insulating sheet 57 and the heating cylinder part 51 of the insulating case 52, and as shown in FIG.
9 are caulked to the insulating sheet 57 and the insulating case 52, and the insulating sheet 57 and the insulating case 5 are connected with the metal eyelets 59.
2 are assembled together. This PTC thermistor device 60 is used by inserting a vaporizing core that has sucked up an insecticidal liquid into a metal eyelet 59, and both -l' portions 53, 55 are used.
When PTC thermistor Sosen Soko 61 electric current is applied from PTC
The heat generated from the thermistor element 61 heats the heating cylinder part 51 of the insulating case 252, the heating cylinder part 51 heats the metal eyelet 59, and the metal eyelet 59 heats the vaporizing core to evaporate the insecticidal liquid. It has become.

Note that the insecticidal liquid contains components (for example, chlorine) that shorten the life of the PTC thermistor element 61, so in this PTC thermistor device 60, the cylindrical portion 51 facing the vaporization wick is The joint between the upper end surface and the insulating sheet 57 is covered with a metal eyelet 59.

Next, the positive temperature coefficient thermistor device 7 used in the mat type
6 will be explained. As shown in FIGS. 11 and 12, a flat PTC thermistor element 71 with electrodes formed on both sides sandwiched between electrode plates 77 and 78 is housed in an insulating case 72 with an open top. A mica insulation sheet 73 and a metal mat heat sink 74 are placed on top of the metal plate 7.
5, a mat heat sink 74 and an insulating case 72 are assembled together. In this PTC thermistor device 7G, a mat impregnated with an insecticidal liquid is placed on the mat heat sink 74, and the mat placed on the mat heat sink 74 is heated by the heat generated from the PTC thermistor element 71. The insecticidal liquid impregnated into the mat is allowed to evaporate.

[Problems to be Solved by the Invention] As mentioned above, in conventional positive temperature coefficient thermistor devices, the one used for the liquid method and the one used for the matte method have different structures, There was no structure that could be used in conjunction with the previous method.

Therefore, prior to the present invention, the applicant of the present invention filed Japanese Patent Application No. 1-327028 on December 15, 1989.
We have filed a patent application for a positive temperature coefficient thermistor device that can be used in combination with the liquid method and matte method. This positive temperature coefficient thermistor device (not shown) includes a heating cylinder in the center of an insulating case, element housings each having a bottom opening on both sides of the heating cylinder, and a terminal electrode and a PTC in each element housing. The thermistor element was delivered, the lower opening of the element housing was closed with an insulating sheet, and the insulating case and sheet were crimped together using a metal plate attached to the top of the insulating case. When used in a liquid-type electric mosquito repellent, the vaporizing wick inserted into the heating tube is heated, and when used in a mat-type electric mosquito repellent, the mat is placed on a metal plate and heated. I was supposed to.

However, in a combination type PTC thermistor device with such a structure, two PTC thermistor elements are placed on both sides of the heating cylinder, which complicates the structure of the insulation case and terminal board, and also makes the structure of the terminal board complicated. If the dimensions become too large,
The number of parts for the terminal board increased, resulting in high costs. Furthermore, the external size of the PTC thermistor device has also increased.

In addition, when using the mat method, if the heating temperature of the mat is low, the insecticidal liquid impregnated into the mat will not evaporate completely, and when using the liquid method, if the heating temperature is too high, the evaporation I will be slow. Since the insecticidal liquid will run out within a certain number of days, the mat heating temperature should be 140℃.
~150° C. is preferable, and the vaporizing window heating temperature in the liquid method is preferably about 120° C. In particular, it is necessary that the matte heating temperature>the vaporizing window heating temperature. On the other hand, the heat generation path of the heating cylinder section is through the PTC thermistor element wire insulation case, and the heat generation path of the metal plate is relatively long from the PTC thermistor element to the insulation case to the metal plate, and is due to heat radiation from the metal plate. Heat loss is also large, so in the PTC thermistor device of the earlier invention, in order to adjust the surface temperature of the metal plate for mat heating and the temperature of the vaporizing core heating cylinder to an appropriate value, it is necessary to adjust the structure of the insulating case. There was a problem that it became complicated.

The present invention has been made in view of the above-mentioned conventional example and the invention of the prior application, and relates to a positive temperature coefficient thermistor device that can be used in combination with the mat type and liquid type.

The purpose is to reduce the number of PTC thermistor elements used to one and to obtain an optimal heat generation temperature distribution.

[Means for Solving the Problems] The positive temperature coefficient thermistor device of the present invention is provided with an element storage portion opened at the bottom surface at a position biased to one side from the center of the insulating case having good thermal conductivity, and A through hole penetrating vertically is formed at a position biased to the other side than the above, and a pair of terminal electrodes and one positive temperature coefficient thermistor element are delivered into the element housing, and the lower opening of the element housing is closed with an insulating sheet. , is characterized in that the upper surface of the insulating case and the peripheral side of the through hole are used as heat generating parts for heating.

[Function] The PTC thermistor device of the present invention includes a heat generating part in the through hole through which the vaporizing core is inserted and heated, and a heat generating part on the upper surface side in which the mat is placed and heated. Therefore, it can be used in combination with liquid type electric mosquito repellent and mat type electric mosquito repellent.

Furthermore, since the through hole and each heat generating part on the top surface are heated by one PTC thermistor element, the insulating case and the terminal board can be made smaller, and their structure and shape can also be simplified. Therefore, the cost of the PTC thermistor device can be reduced and it can also be made smaller.

Moreover, since the through hole is provided on one side of the insulating case and the PTC thermistor element is housed on the other side of the center of the insulating case, the distance between the through hole and the PTC thermistor element can be reduced without increasing the size of the PTC thermistor device. The temperature of the through hole can be controlled to be low. Furthermore, since the upper surface of the insulating case is directly used as the heat generating part, the heat generation path of this heat generating part becomes the PTC thermistor element wire insulating case, and heat dissipation is not large unlike the metal plate of the earlier invention. Therefore, the temperature of the heat generating part on the upper surface side surface can be controlled to be high.

As a result, the temperature of the heat generating part for heating the mat can be easily made higher than the temperature of the through hole of the vaporizing core, and favorable heat generating temperature conditions can be obtained.

Furthermore, since the through holes are arranged close to one side and the PTC thermistor element is arranged on the other side, it is possible to uniformly heat the mat.

[Example] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view of an embodiment of the present invention from the bottom side. The insulation case 1 is made of alumina (AIJs).
), etc., and as shown in Fig. 2, one longitudinal end has a through hole 2 opened vertically through which the vaporizing wick is inserted, and the other end has a through hole 2 opened in the vertical direction. A rectangular, circular, etc. element housing portion 3 for storing a PTC thermistor element or the like is recessed in the housing. moreover,
In the lower surface of the insulating case 1, a groove-shaped lead extraction portion 4 extending from the inside of the element storage portion S to both side surfaces of the case is recessed. The PTC thermistor element 5 has a disk shape, and electrodes 6 are formed on both sides.

The PTC thermistor element 5 is not limited to a disk shape, but may also be a square plate shape, a ring shape, etc. However, ring-shaped PTC thermistor elements have large variations in inner circumferential dimensions, and gaps are likely to occur between them and the insulating case. Therefore, a flat PTC thermistor element such as a disk shape or a square plate shape is preferable. The child terminal 7 is made of a metal material such as stainless steel, and includes a terminal electrode 8 and a lead portion 9 for contacting one electrode 6 of the PTC thermistor element 5. Moreover, the spring terminal 10 is
It consists of a terminal electrode 11 having spring properties and a lead portion 12. First, the terminal electrode 8 of the child terminal 7 is fitted into the element storage part 3 of the insulating case 1, and the lead part 9 of the child terminal 7 is placed in one of the lead draw-out parts 4 of the insulating case 1. Insert the PTC thermistor element 5 into the element housing part 3 from above, fit the terminal electrode 11 of the spring terminal 10 into the element housing part 3 so that it comes into contact with the PTC thermistor element 5, and then insert the lead part 12 of the spring terminal 10 into the element housing part 3. It is stored in the other lead pullout section 4 of the insulating case 1. and,
The element housing portion 3 is placed in contact with the spring terminal 10.
An internal insulating sheet 13 made of A1□03 or the like having the same size as the element housing part 3 is fitted therein to close the lower opening of the element housing part 3 of the insulating case 1. Furthermore, internal insulation sheet 13
Adhesive is applied to the outer surface of the insulating case 1, and an insulating sheet 14 made of an insulating material such as A+i0 is stacked on the lower surface of the insulating case 1, and the protrusion 15 provided on the insulating sheet 14 is fitted into the element storage part S. Then, the internal insulating sheet 13, the protrusion 15, and the element housing part 3 are adhered to each other with an adhesive, and the element housing part 3 is sealed. Note that 18 is a through hole provided opposite to the through hole 2.

In this way, by forming the insulating case 1 and the internal insulating sheet 13 into a sealed structure, the PTC thermistor element 5 becomes less susceptible to the influence of outside air such as chlorine gas.

Furthermore, it is possible to prevent foreign matter from entering from the outside, and to prevent the PTC thermistor element 5 from deteriorating. In addition, since the protrusion 15 is glued inside the element storage part S, the protrusion 15 holding down the terminal electrode 11 and the insulating sheet 13 does not lift up, and as shown in FIG. As a result, both terminal electrodes 8 and 11 can be brought into reliable contact with the PTC thermistor element 5, and contact failures between the child terminal 7 and the spring terminal 10 can be prevented. The insulating sheet 14 is provided with a pair of claw pieces 16, and by hooking the claw pieces 16 onto the stepped portion 17 of the insulating case 1 as shown in FIG.
4 and the insulating case 1 are integrated to assemble the PTC thermistor device 20.

Therefore, when the PTC thermistor element 5 is energized through the child terminal 7 and the spring terminal 10, the heat of the PTC thermistor element 5 is radiated from the inner peripheral surface of the through hole 2 through the insulating case 1, and also through the insulating case 1. Heat is radiated from the upper surface 19, and each serves as a heat radiating portion. Moreover, the upper surface 19 of the insulating case 1 is directly used as a heat generating part to shorten the heat dissipation path and reduce the heat radiation (in addition, by separating the PTC thermistor element 5 and the through hole 2 to both sides of the insulating case 71, the heat dissipation temperature of the through hole 2 is reduced. (The temperature of the through hole 2 can be adjusted by adjusting the distance between the PTC thermistor element 5 and the through hole 2.), and the temperature of the upper surface 19 (about 14o~150°C) is lower than the temperature of the through hole 2 (about 120°C). In addition, since the through hole 2 is provided at a position biased to one side of the insulating case 1 and the PTC thermistor element 5 is arranged on the other side, the upper surface from the PTC thermistor element 5 is The distance to the end of the PTC thermistor element 5 does not become large, and the temperature distribution on the upper surface 19 can be made uniform.Furthermore, by using only one PTC thermistor element 5, the distance between the PTC thermistor element 5 and the element storage part 8 can be made uniform. The surroundings can be easily sealed, and the PTC thermistor element 5 can be more reliably protected from deterioration due to outside air.

The positive temperature coefficient thermistor device 20 can be used for both a liquid-type electric mosquito repellent and a mat-type electric mosquito repellent, and can be used in both types. For example, FIGS. 7 and 8 are cross-sectional views of an electric mosquito repellent 24 that can be used in both a liquid method and a mat method. This is a case 25 in which a bottle storage chamber 2G is formed.

When the positive temperature coefficient thermistor device 20 is used as a liquid type, a chemical liquid bottle 28 containing an insecticidal liquid is placed in the bottle storage chamber 26, as shown in FIG. This chemical liquid bottle 28 has a felt-like or fiber-like vaporizing wick 2θ, which is capable of sucking up liquid by capillary action, inserted into the lid 30, the lower part is immersed in the insecticidal liquid, and the upper end protrudes upward. This is what I did. Thereafter, the positive temperature coefficient thermistor device 20 is delivered into the case 25 by inserting the upper part of the vaporization core 29 into the through hole 2, and the case 25 is used by covering the case 25 with a frame-shaped lid 27. At this time, the PTC thermistor device 20 connects the tip of the insulating sheet 14 to the bottle storage chamber 26.
It is secured to a shelf 32 on the inner wall surface of the holder. In this way, P.T.
When the C thermistor element 5 is energized to generate heat, the heat is PT
Heat is conducted from the C-therminuta element 5 to the through hole 2 to the vaporization core 29, and the vaporization core 29 can be heated. The sucked-up insecticidal liquid is evaporated from the heated vaporizing wick 2θ and diffused into the surroundings.

Next, when using the PTC thermistor device 20 as a mat type, as shown in FIG. A mosquito repellent mat) 31 is placed, and the insecticidal liquid impregnated into the mat 31 is evaporated by the positive temperature coefficient thermistor device 20. In this case as well, heat is conducted through a path with good thermal conductivity, such as PTC thermistor element 5 → upper surface 19 of insulating case 1 → mat 31, and the mat is heated.

What is shown in FIGS. 5 and 6 is a positive temperature coefficient thermistor device 33 according to another embodiment of the present invention, in which a flat terminal 7, a spring terminal 10. An insulating sheet 14 is placed over the insulating case AE in which the PTC thermistor element 5 and the internal insulating sheet 13 are delivered, and the metal plate 3 is attached from above the insulating sheet 14.
The insulating case 1 and the insulating sheet 14 are integrated by caulking the claw pieces 35 of 4 to the insulating case 1. Note that 3θ is a hole through which the vaporizing core is inserted.

[Effects of the Invention] According to the present invention, the number of PTC thermistor elements used can be reduced to 1.
By making the PTC thermistor device individual, it is possible to downsize the PTC thermistor device that uses both the matte method and the liquid method, and also to reduce the cost. Further, the temperature of the heat generating part for heating the mat could be made higher than the temperature of the heat generating part for heating the vaporizing core, and favorable heat generating temperature conditions for the mat and the vaporizing core could be realized. Furthermore, even though the heating section on the top surface is heated by a single PTC thermistor element, the temperature distribution of this heating section can be made uniform, making it possible to heat the mat evenly. .

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing an embodiment of the present invention turned upside down, Fig. 2 is a bottom view of the same insulation cake, Fig. 3 is a perspective view showing the same assembled state, and Fig. 4 is a XX in figure 3
A line sectional view, FIG. 5 is a perspective view showing another embodiment of the present invention,
Fig. 6 is a partially exploded perspective view of the same as the above, Fig. 7 is a schematic sectional view of a liquid type electric mosquito repellent using the PTC thermistor device of the present invention, and Fig. 8 is a schematic cross-sectional view of a liquid type electric mosquito repellent using the PTC thermistor device of the present invention. A schematic cross-sectional view of a mat-type electric mosquito repellent station.
FIG. 9 is an exploded perspective view showing a conventional positive temperature coefficient thermistor device, FIG. 10 is a sectional view of FIG. 9, FIG. 11 is an external perspective view of another conventional example, and FIG. 12 is a side view of FIG. 11. FIG. 1...Insulating case 2...Through hole 3...Element storage part 5...PTC thermistor element 8.11...Terminal electrode 14...Insulating sheet 16...Claw piece 1θ... Top patent applicant Murata Manufacturing Co., Ltd. Figure 2 Figure 3 Figure 4 Figure 5! 6 Factors Figure 7 Figure 8 Figure 11 Figure 12 U) O/l convex

Claims (1)

[Claims] (1) An element storage section with an open bottom is provided at a position biased to one side of the center of the insulating case with good thermal conductivity, and a through hole penetrating vertically is provided at a position biased to the other side of the center of the insulating case. A pair of terminal electrodes and a positive temperature coefficient thermistor element are delivered into the element housing, and the lower opening of the element housing is closed with an insulating sheet, and the upper surface of the insulating case and the peripheral side of the through hole are used for heating. A positive temperature coefficient thermistor device characterized in that the heat generating part is a positive temperature coefficient thermistor device.