JP2584496Y2 - Positive characteristic thermistor device - Google Patents

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, and more particularly, to a positive temperature coefficient thermistor device used in a mosquito catcher or a fragrance device of a liquid vaporization type.

[0002]

2. Description of the Related Art As a conventional positive temperature coefficient thermistor device used in a mosquito catcher of the liquid vaporization and diffusion type, there is a positive temperature coefficient thermistor device as shown in FIGS. 4 is an exploded perspective view, FIG. 5 is a plan view, and FIG. 6 is a front sectional view.

The heater mechanism of this conventional positive temperature coefficient thermistor device includes a radiating tube 51 into which a liquid suction core is inserted, an insulating layer 52 covering the outer peripheral surface of the radiating tube 51, and an insulating layer 52 which is brought into close contact with the insulating layer 52. And a pair of electrode plates (heat sinks) 53, 54 opposed to each other via the fins, and flat plate portions 53 a, 54 protruding to the side end side of the radiation plates 51 of the electrode plates 53, 54.
a, thermistor elements 55, 56 mounted between the respective plate surfaces a, 53b, 54b. In addition, lead terminals 53f and 54f are extended on different side ends of the electrode plates 53 and 54, respectively. The electrode plate 5
A curved portion 53 is provided at a portion facing
c, 54c are formed.

A portion other than the heat radiating tube 51 of the heater mechanism portion formed by combining these members is held by holding portions 57a, 57 of a case body 57 made of an insulating material such as resin.
b, and after fitting a case lid 58 made of an insulating material to the case main body 57, insert the radiator tube 51 through the hole 58a of the case lid 58, and insert the flange portion 5 on the upper end side.
By caulking the lower end portion 51b with the 1a in contact with the case lid 58, the positive temperature coefficient thermistor device used in the above-described liquid vaporization and diffusion type mosquito trap is formed.

The electrode plates 53, 54 for holding the PTC thermistor elements 55, 56 are in contact with the holding portions 57a, 57b of the case body 57, and the PTC thermistor elements 55, 54 are located between the electrode plates 53, 54. Protrusions 53g, 54g, 53h, and 54h for applying an urging force for clamping the pin 56 are formed.

[0006]

However, in the above-mentioned conventional positive temperature coefficient thermistor device, in order to conform to a prescribed external withstand voltage regulation, the current path between the electrode plates (heat sinks) 53 and 54 and the radiating tube 51 is required. 6, that is, the distance between the upper end P of the portion where the electrode plate 53 is in contact with the insulating layer 52 and the portion Q of the radiator cylinder 51 facing the upper end P in FIG. Insulating layer 5
2 needs to be increased in thickness. Therefore, not only is there a problem that the device is enlarged, but also there is a problem that the efficiency of heat transfer from the electrode plates 53 and 54 to the radiator tube 51 is reduced.

As described above, when the heat transfer efficiency to the heat radiating tube 51 is reduced, the Curie point of the positive temperature coefficient thermistor elements 55 and 56 used is increased to transfer a predetermined amount of heat, thereby reducing the heat transfer efficiency. It is necessary to make up for it. But,
If the Curie points of the positive characteristic thermistor elements 55 and 56 are increased, high performance is required due to the heat resistance of the case body 57 and the case lid 58 made of an insulating material such as a resin, which not only increases the cost but also increases the cost. However, there is a problem that reliability is reduced.

The electrode plates 53 and 54 and the lead terminals 53
f and 54f are integrally formed, and when the lead terminals 53f and 54f are formed using a material having high thermal conductivity,
Since the heat radiation from the lead terminals 53f and 54f increases, the heat generation of the positive temperature coefficient thermistor elements 55 and 56 is
2 cannot be efficiently transmitted to the heat radiating tube 51 via the radiator 2.

The present invention solves the above-mentioned problems, and provides a highly reliable positive-characteristic thermistor device that can be downsized, can efficiently transmit the heat generated by the positive-characteristic thermistor element to the radiating cylinder, and can be highly reliable. The purpose is to provide.

[0010]

In order to achieve the above object, a positive temperature coefficient thermistor device according to the present invention includes a positive temperature coefficient thermistor element, a metal radiating tube into which an object to be heated is fitted inside, and a heat radiation tube. A lower insulating case provided with a cylindrical heat radiating tube holding portion that contacts and holds the outer peripheral surface of the heat radiating tube, and is fitted to the heat radiating tube holding portion of the lower insulating case so as to have a predetermined fitting depth. An upper insulating case with a cylindrical fitting and a PTC thermistor element are sandwiched from both sides.
To transfer the heat generated by the PTC thermistor element to the radiator tube.
And a pair of heat sinks.
The heat sink holding part of the lower insulation case and the upper insulation case
A spring having a curved portion corresponding to the outer peripheral surface of the coupling structure portion so that the outer peripheral surface of the coupling structure portion is in close contact with at least a part of the outer peripheral surface of the coupling structure portion formed by fitting the cylindrical fitting portion of the spring. Sex
Terminals have at least one heat sink
By pressing the characteristic thermistor element, a pair of heat
Tosink and PTC thermistor element are in close contact and both are conductive
The heat sink serves as a current path,
The heat transfer of the heat from the both sides of the
A heat path is used to heat the object to be heated to a predetermined temperature.
And a radiator tube of the lower insulating case
Between the upper end side of the holding portion and the cylindrical fitting portion of the upper insulating case.
At least one of the lower ends is fitted with
In the thickness direction of the heat cylinder, the upper end side of the heat radiating cylinder holding part and the cylindrical fitting part
In order to form a part where the lower end overlaps,
Fit the bottom end outside or inside the top end of the radiator holder
And fit them together.
By overlapping the lower end of the engaging portion, the heat sinks, release
Through the fitting part between the hot cylinder holding part and the cylindrical fitting part, the outer circumference of the heat radiating cylinder
The distance to the surface (insulation distance) depends on
Structured to be larger than the thickness of the overlapping part of the shape fitting part
It is characterized by being.

Further, the present invention is characterized in that a safety device is provided which cuts off the power supply to the positive temperature coefficient thermistor element when an abnormal current flows.

[0012]

[Function] The upper end side of the radiating tube holding portion of the lower insulating case and the upper side.
At least one of the lower end sides of the cylindrical fitting part of the part insulating case
At the lower end of the cylindrical fitting portion so that the two fit together.
Into the outside or inside of the upper end side of the heat radiating tube holder.
The two are fitted together, and the thickness of the
A portion where the end side and the lower end side of the cylindrical fitting portion overlap is formed.
From the heat sink, the radiating cylinder holding part and the cylindrical
Distance from the fitting part of the fitting part to the outer peripheral surface of the radiation tube
Separation (insulation distance) (for example, the heat sink 9a,
9b and a cylindrical fitting portion of the upper insulating case 6
5) (the distance to the lower end Q of the inner circumference) can be increased
And increase the thickness of the radiating tube holding part and the cylindrical fitting part
Required insulation distance without the need for
Heat transfer efficiency can be improved while maintaining withstand voltage
Become.

Further, the heat sink and the power supply terminal are formed as separate members, and the positive temperature coefficient thermistor element is sandwiched between a pair of heat sinks. Make sure that the thermistor element
As a result, the heat generated by the positive temperature coefficient thermistor element is efficiently transmitted to the radiator through a pair of heat sinks from both sides thereof, and the heat sink and the terminal (lead terminal)
Compared with the case where the components are integrally formed, the heat radiation from the heat sink is suppressed, and the heat transfer efficiency can be improved .

Further, by incorporating a safety device which blows off when an abnormal current flows, it becomes possible to prevent the occurrence of an accident by stopping the power supply to the positive characteristic thermistor element when an abnormality occurs.

[0015]

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 showing a PTC thermistor device according to an embodiment of the present invention, FIG. 2 is a perspective view showing an assembled PTC thermistor device, and FIG. FIG. 3 is a sectional view taken along line III.

As shown in these figures, the positive temperature coefficient thermistor device of this embodiment comprises a positive temperature coefficient thermistor element 1, a metal radiating tube 2 into which an object to be heated is fitted, and a radiating tube 2
A lower insulating case 4 made of resin and having a radiating tube holding portion 3 formed in a cylindrical shape so that the radiating tube holding portion 3 of the lower insulating case 4 can be fitted. 5 and a resin-made upper insulating case 6 and at least a part of an outer peripheral surface of a joint structure portion 7 (FIG. 3) formed by fitting the heat-radiating tube holding portion 3 and the cylindrical fitting portion 5. In addition, it has curved portions 8a and 8b corresponding to the outer peripheral surface of the coupling structure portion 7, and generates heat of the positive temperature coefficient thermistor element 1 to the heat radiating tube 2 through the heat radiating tube holding portion 3 and the cylindrical fitting portion 5. A pair of heat sinks (usually formed of a good conductor of heat such as brass or aluminum) 9a, 9b for transmitting the object to be heated to a predetermined temperature
It is comprised including. At opposite positions of the lower insulating case 4, the PTC thermistor devices are attached to the mosquito catcher or the like easily without specially preparing other members. Is provided.

The radiating tube holding portion 3 and the cylindrical fitting portion 5
And, as shown in FIG. 3, one another while mating the inside of the tip of the tubular fitting portion 5 is radiating tube holding portion 3, so as to fit to a predetermined depth, the heat radiation tube holder Inner circumference of the upper end of 3
A cylindrical portion having a large inner diameter is formed on the inner surface of the radiating tube 2, and an inner peripheral surface of a coupling structure portion 7 formed by fitting the radiating tube holding portion 3 and the cylindrical fitting portion 5 is formed with an outer peripheral surface of the radiating tube 2. It is configured to be in close contact. Chi words, among the upper end of the radiator tube holder 3
Under the cylindrical fitting part 5,
When the end side enters, heat is dissipated in the thickness direction of the radiation tube 2.
A cylindrical portion having a large inner diameter at the upper end side of the cylindrical holding portion 3 and a cylindrical fitting portion 5
Are formed so that the lower ends thereof overlap. In addition,
It is also possible to configure so that the distal end side of the cylindrical fitting portion 5 fits outside the heat radiating tube holding portion 3.

The positive temperature coefficient thermistor element 1 is sandwiched between flat plates 10a and 10b of a pair of heat sinks 9a and 9b, and one heat sink 9a is positively connected to a power supply terminal A having a spring property. The characteristic thermistor element 1 is pressed. FIG. 1A shows the shape of the spring structure 11 at the tip of the terminal A.

The other heat sink 9 b is connected to the terminal B inserted into the terminal holding portion 17, is pressed by the terminal B, and is in close contact with the coupling structure 7. The terminal B is formed in a curved shape corresponding to the heat sink 9b, and is formed with a protrusion 12 for contact with the heat sink 9b at the distal end side of the three strips, so that the terminal B is connected to the heat sink 9b. It is configured to secure a contact capacity of. Note that one end of the terminal B is configured to be electrically connected to an external terminal 13b of a safety device (glass tube fuse) 13 described below.

Further, the positive temperature coefficient thermistor device of this embodiment incorporates a safety device (glass tube fuse) 13 for fusing and stopping energization when an abnormal current flows. The safety device 13 is inserted and held in a safety device holding portion 14 provided in the lower insulating case 4. And
The terminal C inserted into the terminal holding portion 18 is connected to one external terminal 13a of the safety device (glass tube fuse) 13, and the spring structure portion 15 presses the external terminal 13a. The other external terminal 13b of 13 and the terminal B are securely connected. FIG. 1B shows the shape of the spring structure 15 at the tip of the terminal C.

Next, an assembling process of the PTC thermistor device will be described. In assembling the PTC thermistor device of this embodiment, first, a pair of heat sinks 9a and 9b sandwiching the PTC thermistor element 1 are attached to the lower insulating case 4 and the terminal A having the spring structure 11 is connected to the lower insulating case. 4, the flat plate portion 10a of one heat sink 9a is pressed and brought into close contact with the PTC thermistor element 1. then,
A safety device (glass tube fuse) 13 is attached to the safety device holding portion 14 of the lower insulating case 4, and the heat sink 9 b and the safety device 13 are electrically connected at the terminal B, and the terminal C connected to the safety device 13 is externally connected. Pull out.

Next, the upper insulating case 6 is attached to the lower insulating case 4 and the upper and lower insulating cases 4 and 6 are connected by fitting the radiator tube 2 into the upper insulating case 6 and caulking the upper part thereof. Then, the fitting portions 19 of the upper and lower insulating cases 4 and 6 are formed.
By applying an adhesive 20 to (FIGS. 2 and 3) and forming the fitting portion 19 into a simple hermetic structure, a PTC thermistor device as shown in FIGS. 2 and 3 is assembled.

In the PTC thermistor device constructed as described above, the lower insulating case 4
And the cylindrical fitting portion 5 of the upper insulating case 6
Doo is fitted to a predetermined insertion depth, the thickness of the heat radiation tube 2
Tube part with a large inner diameter on the upper end side of the heat radiating tube holding part 3
And the lower end side of the cylindrical fitting portion 5 overlaps, so that the insulation distance (that is, the heat sink 9 in FIG.
The distance from the inner peripheral upper end P of the upper and lower insulating case 6 to the inner peripheral lower end Q of the cylindrical fitting portion 5 of the upper insulating case 6 can be increased. Therefore, the required insulation distance can be ensured without increasing the thickness of the radiating tube holding portion 3 and the cylindrical fitting portion 5, and the heat transfer efficiency can be improved. Can be reduced in size and power can be saved, and the whole PTC thermistor device can be reduced in size.

The heat sinks 9a, 9b and the terminals A,
B and C are formed as separate members, and the positive temperature coefficient thermistor element 1 is sandwiched between a pair of heat sinks 9a and 9b. Since the both sides of the thermistor element 1 are brought into close contact with each other,
The heat generated by the positive temperature coefficient thermistor element 1 can be efficiently transmitted from both sides to the heat radiating tube 2 via the heat sinks 9a and 9b, and the heat sink (electrode plate) and the terminal (lead terminal) are integrated as in the conventional example. The heat transfer from the heat sinks 9a and 9b can be suppressed and the heat transfer efficiency can be improved as compared with the case of the above-described configuration.

Furthermore, since a safety device (glass tube fuse) 13 that blows when an abnormal current flows is incorporated, the power supply to the PTC thermistor element 1 is stopped when an abnormality occurs, thereby reliably preventing the occurrence of an accident. can do.

In the above embodiment, the case where a glass tube fuse is used as the safety device 13 has been described. However, the safety device is not limited to the glass tube fuse, and other types of fuses may be used. Terminal A,
It is also possible to form a part of B and C so as to be melted when an abnormal current flows and to function as a safety device.

The PTC thermistor device of the present invention is not limited to the above-described embodiment, but includes the specific shape of the radiator tube, the fitting depth of the radiator tube holding portion and the cylindrical fitting portion, and the upper and lower portions. Regarding the structure of the insulating case, etc., the specific shape of the heat sink, and the structure of the spring structure of each terminal, etc.
Various applications and modifications can be made within the scope of the present invention.

[0029]

As described above, the positive temperature coefficient thermistor device according to the present invention is provided at the upper end side of the radiating tube holding portion of the lower insulating case.
And at least the lower end side of the cylindrical fitting portion of the upper insulating case.
On the other hand, beneath the cylindrical fitting part so that they fit together
Insert the end into the outside or inside of the upper end of the radiator holder
And fit them together, and hold the radiator tube in the thickness direction of the radiator tube.
A portion where the upper end side of the cylindrical part overlaps the lower end side of the cylindrical fitting portion is formed.
So that the heat sink can be held from the heat sink.
To the outer peripheral surface of the heat radiating tube via the fitting part between the part and the cylindrical fitting part
Distance (insulation distance) can be increased.
You. Therefore, the thickness of the radiating tube holding part and the cylindrical fitting part must be large.
Necessary insulation distance can be secured without making
And improve the heat transfer efficiency while maintaining the withstand voltage
Becomes possible. As a result, the size of the PTC thermistor element 1 can be reduced to save power, and the thickness of the radiating tube holding portion and the tubular fitting portion can be reduced to reduce the size of the PTC thermistor device as a whole. It becomes possible.

Further, the positive temperature coefficient thermistor device of the present invention comprises:
The heat sink and the terminal are formed as separate members, and the positive temperature coefficient thermistor element 1 is sandwiched between a pair of heat sinks, and one heat sink is pressed by a spring-like terminal to bring both surfaces of the heat sink and the positive temperature coefficient thermistor element into close contact. With this configuration, the heat generated by the positive temperature coefficient thermistor element can be efficiently transmitted from both sides to the radiator via the heat sink, and the heat transfer from the heat sink can be suppressed to improve the heat transfer efficiency.

Further, a positive temperature coefficient thermistor device according to claim 2
As described above, by incorporating a safety device that blows when an abnormal current flows, power supply to the PTC thermistor element can be stopped when an abnormality occurs, thereby preventing an accident from occurring.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing a PTC thermistor device according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of the PTC thermistor device according to one embodiment of the present invention, taken along line III-III of FIG. 2;

FIG. 4 is an exploded perspective view showing a conventional PTC thermistor device.

FIG. 5 is a plan view showing a conventional PTC thermistor device.

FIG. 6 is a front sectional view showing a conventional PTC thermistor device.

[Explanation of symbols]

A, B, C Terminals P Upper end of inner circumference of heat sink Q Lower end of inner circumference of cylindrical fitting 1 Positive temperature coefficient thermistor element 2 Heat sink 3 Heat sink holding part 4 Lower insulating case 5 Tubular fitting 6 Upper insulation Case 7 Coupling structure 8a, 8b Curved shape 9a, 9b Heat sink 10a, 10b Flat plate 11, 15 Spring structure 12 Projection 13 Safety device (glass tube fuse)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01C 7/02-7/22

Claims (2)

(57) [Scope of request for utility model registration] 1. A positive temperature coefficient thermistor element, a metal heat radiating tube into which an object to be heated is inserted, and a cylindrical heat radiating tube holding portion which is in contact with and holds the outer peripheral surface of the inserted heat radiating tube. A lower insulating case, a upper insulating case having a cylindrical fitting portion fitted to the heat radiating tube holding portion of the lower insulating case so as to have a predetermined fitting depth, and a positive temperature coefficient thermistor element on both sides thereof Pinched from
A pair of heaters that transmit the heat of the conductive thermistor element to the radiator tube
And a pair of heat sinks,
Heat-dissipating cylinder holding part of upper insulating case and cylindrical shape of upper insulating case
A terminal having a curved shape portion corresponding to the outer peripheral surface of the coupling structure portion so as to be in close contact with at least a part of the outer peripheral surface of the coupling structure portion to which the fitting portion is fitted , and having a spring property. At least one heat sink
Is pressed against the PTC thermistor element,
A pair of heat sink and PTC thermistor
Is conducted, the heat sink becomes the current path,
The heat of the characteristic thermistor element is transmitted to the radiator from both sides.
Heat transfer path reaches the target to be heated
And the upper end side of the radiating tube holding portion of the lower insulating case and the upper side.
At least one of the lower end sides of the cylindrical fitting part of the part insulating case
In addition, both are fitted to each other,
The part where the upper end of the holding part and the lower end of the cylindrical fitting part overlap
So that the lower end of the tubular fitting part is
Fit into the outside or inside of the upper end side, fit both,
The upper end of the radiator holder and the lower end of the cylindrical fitting part overlap.
Then, from the heat sink, the radiating cylinder holding part and the cylindrical fitting part
Distance through the mating part of
Edge distance) of the overlapping part of the radiating tube holding part and the cylindrical fitting part
A positive temperature coefficient thermistor device configured to be larger than a thickness . 2. The positive temperature coefficient thermistor device according to claim 1, further comprising a safety device for fusing when an abnormal current flows and stopping power supply to the positive temperature coefficient thermistor element.