JP7124740B2 - temperature sensor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a temperature sensor that can be easily attached to an object to be measured and has excellent responsiveness.

2. Description of the Related Art Conventionally, temperature sensors are known in which a chip-shaped or flake-shaped thermistor element is attached to a crimp terminal.
In this temperature sensor, a crimp terminal, which is a so-called R terminal, is provided with an annular portion that can be attached with a screw. By doing so, the temperature sensor can be easily screwed to the object to be measured.

For example, as shown in FIG. 7, Patent Document 1 has a thermal element section 102, a screw attachment section 104 that can be fixed to an object to be measured with a screw, and a bottom section 105 to which the thermal element section 102 is attached. The thermosensitive element portion 102 includes a crimp terminal 106, an insulating film 107 adhered to the upper surface of the bottom portion 105 with an adhesive G, a thermistor element 108 provided on the upper surface of the insulating film 107, and a thermistor at one end. A temperature sensor is proposed that includes a pair of patterned wirings 109 connected to the element 108 and formed on the surface of the insulating film 107 .

JP 2018-124125 A

The following problems remain in the above conventional technique.
Conventionally, an adhesive G such as an epoxy-based adhesive is applied to the bottom portion 105 of the crimp terminal 106 to adhere the insulating film 107 thereto. In some cases, the insulating film 107 was peeled off due to the shear stress of . In addition, since the adhesive G is interposed between the insulating film 107 and the crimp terminal 106, the thermal responsiveness is deteriorated due to the heat insulating property of the adhesive G. Furthermore, when the insulating film 107 is adhered with the adhesive G, there is also a risk of misalignment.

The present invention has been made in view of the above-mentioned problems, and has high thermal responsiveness, does not cause peeling of the insulating film during lead wire soldering, etc., and prevents misalignment during adhesion of the insulating film. An object of the present invention is to provide a temperature sensor capable of

In order to solve the above problems, the present invention employs the following configurations. That is, a temperature sensor according to a first aspect of the invention includes a thermal element portion, a pair of lead wires having one end connected to the thermal element portion, a screw mounting portion that can be fixed to an object to be measured with a screw, and the thermal element portion. a crimp terminal having a bottom portion to which is attached, the thermal element portion being an insulating film provided on the upper surface of the bottom portion; and a thermal element provided on the upper surface of the insulating film; a pair of pattern wirings formed on the upper surface of the insulating film, one end of which is connected to the thermal element and the other end of which is connected to the pair of lead wires, the bottom portion having a plurality of protrusions on the upper surface; The insulating film has a plurality of positioning holes formed at positions corresponding to the plurality of protrusions and through which the protrusions are inserted, and the protrusions are covered on the upper surface of the insulating film. In addition, a hole-filling resin portion for filling at least the positioning hole is formed.

In this temperature sensor, the bottom portion has a plurality of projections on the top surface, and the insulating film has a plurality of positioning holes formed at positions corresponding to the plurality of projections and through which the projections are inserted. Since the hole-filling resin portion is formed on the upper surface of the insulating film to cover the projections and fill at least the positioning holes, the insulating film is positioned by the projections and the positioning holes and is firmly fixed by the hole-filling resin portion. be. In addition, the heat of the bottom portion is transmitted to the upper surface side of the insulating film provided with the heat-sensitive element by the convex portion and the hole-filling resin portion, and high thermal responsiveness can be obtained.

A temperature sensor according to a second invention is the temperature sensor according to the first invention, in which a pattern is formed on the upper surface of the insulating film with a material having a higher thermal conductivity than the insulating film, and extends from the hole-filling resin part to the thermosensitive element. It is characterized by having a heat-conducting pattern that is present.
That is, in this temperature sensor, a pattern is formed on the upper surface of the insulating film with a material having a higher thermal conductivity than the insulating film, and has a heat conducting pattern extending from the hole-filling resin portion to the heat sensitive element. The thermal conductive pattern with high thermal conductivity serves as a thermal coupling route between the hole-filling resin portion and the thermal element, further improving the thermal responsiveness.

A temperature sensor according to a third invention is characterized in that, in the second invention, the heat conducting pattern extends along the pattern wiring from the vicinity of the heat sensitive element.
That is, in this temperature sensor, since the heat-conducting pattern extends along the pattern wiring from the vicinity of the heat-sensitive element, heat from the pattern-wiring side is guided to the heat-sensitive element side by the highly heat-conductive heat-conducting pattern. As a result, higher thermal responsiveness can be obtained, and heat radiation from the lead wires connected to the pattern wiring can be suppressed.

A temperature sensor according to a fourth invention is characterized in that, in the second or third invention, the heat-conducting pattern extends in a U-shape surrounding the heat-sensitive element.
That is, in this temperature sensor, the heat-conducting pattern extends in a U-shape surrounding the heat-sensitive element. can be transmitted to and higher thermal responsiveness can be obtained.

A temperature sensor according to a fifth invention is characterized in that, in any one of the first to fourth inventions, the hole-filling resin portion is made of a material having a higher thermal conductivity than the insulating film. do.
That is, in this temperature sensor, since the hole-filling resin portion is made of a material having a higher thermal conductivity than the insulating film, the hole-filling resin portion with high thermal conductivity further insulates the heat from the bottom portion and the convex portion. can be efficiently transmitted to the upper surface side of the film.

A temperature sensor according to a sixth invention is characterized in that, in any one of the first to fifth inventions, the positioning hole is an elongated hole.
That is, in this temperature sensor, since the positioning hole is an elongated hole, since the positioning hole of the elongated hole is filled with the hole-filling resin portion, the bottom portion of a wide range can be covered by the elongated hole-filling resin portion. Heat can be induced to the top side.

A temperature sensor according to a seventh invention is characterized in that, in any one of the first to sixth inventions, the hole-filling resin part extends from the vicinity of the thermal element along the pattern wiring. do.
That is, in this temperature sensor, since the hole-filling resin portion extends along the pattern wiring from the vicinity of the thermal element, the hole-filling resin portion can guide the heat of the pattern wiring side to the thermal element side. , higher thermal responsiveness can be obtained, and heat radiation from the lead wires connected to the pattern wiring can be suppressed. In particular, by adopting a hole-filling resin portion with high thermal conductivity, it is possible to obtain even higher thermal responsiveness and heat radiation suppression effect.

ADVANTAGE OF THE INVENTION According to this invention, there exist the following effects.
That is, according to the temperature sensor of the present invention, the bottom portion has a plurality of protrusions on the top surface, and the insulating film is formed at positions corresponding to the plurality of protrusions, and the plurality of protrusions are inserted through the insulating film. Since the insulating film has the positioning holes and the hole-filling resin portion is formed on the upper surface of the insulating film to cover the protrusions and fill at least the positioning holes, the insulating film is positioned by the protrusions and the positioning holes and the holes are filled. It is firmly fixed by the resin part. In addition, the heat of the bottom portion is transmitted to the upper surface side of the insulating film provided with the heat-sensitive element by the convex portion and the hole-filling resin portion, and high thermal responsiveness can be obtained.
Therefore, the temperature sensor of the present invention has high thermal responsiveness, does not cause peeling of the insulating film during lead wire soldering, etc., and can prevent misalignment when the insulating film is adhered.

1 is a plan view of essential parts showing a first embodiment of a temperature sensor according to the present invention; FIG. FIG. 3 is a plan view showing a main portion (a) and a heat-sensitive element portion (b) of the crimp terminal in the first embodiment; FIG. 5 is a plan view showing a state in which the projection is inserted into the positioning hole and the thermal element is placed on the crimp terminal in the first embodiment. FIG. 4 is a plan view of a main part showing a state in which a hole-filling resin portion is formed in the first embodiment; FIG. 6 is a plan view of the essential parts showing a second embodiment of the temperature sensor according to the present invention; FIG. 11 is a plan view of a main part showing a third embodiment of a temperature sensor according to the present invention; 1 is an exploded perspective view showing a conventional example of a temperature sensor according to the present invention; FIG.

A first embodiment of a temperature sensor according to the present invention will be described below with reference to FIGS. 1 to 4. FIG. In addition, in each drawing used for the following explanation, the reduced scale is appropriately changed in order to make each member recognizable or easily recognizable.

As shown in FIGS. 1 and 2, the temperature sensor 1 of this embodiment can be fixed to a thermosensitive element portion 2, a pair of lead wires 3 having one end connected to the thermosensitive element portion 2, and an object to be measured with screws. crimp terminal 6 having a screw mounting portion 4 and a bottom portion 5 to which the heat sensitive element portion 2 is mounted.
The thermal element portion 2 includes an insulating film 7 provided on the upper surface of the bottom portion 5, a thermal element 8 provided on the upper surface of the insulating film 7, and one end connected to the thermal element 8 and the other end connected to the thermal element 8. are connected to the pair of lead wires 3 and a pair of pattern wirings 9 formed on the upper surface of the insulating film 7 .

The bottom surface portion 5 has a plurality of convex portions 5a on its upper surface.
In this embodiment, convex portions 5a having a circular shape in plan view are arranged near both sides of the thermal element 8 and near both sides of the pair of pattern wirings 9, respectively.
The insulating film 7 has a plurality of positioning holes 7a formed at positions corresponding to the plurality of projections 5a and through which the projections 5a are inserted.
A hole-filling resin portion 10 is formed on the upper surface of the insulating film 7 to cover the protrusion 5a and fill at least the positioning hole 7a.

The hole-filling resin portion 10 is made of a material having a higher thermal conductivity than the insulating film 7 .
When the insulating film 7 is made of a polyimide resin, the hole-filling resin portion 10 is a resin containing a filler such as glass or SiC, which has a higher thermal conductivity than the polyimide resin.
In addition, the hole-filling resin portion 10 may be, for example, an epoxy resin to which 40 to 50% calcium carbonate is added as a filler, such as a high thermal conductive resin having a thermal conductivity of 0.5 W/(m·K), or an epoxy resin. A high thermal conductive resin having a thermal conductivity of 0.8 to 1.5 W/(m·K) and having 70 to 80% aluminum oxide added as a filler can be used.

The positioning hole 7a is an elongated slit-like elongated hole extending along the pattern wiring 9 from the vicinity of the heat sensitive element 8. As shown in FIG. Two protrusions 5a are inserted into the positioning hole 7a.
That is, the pair of positioning holes 7a are arranged on both sides of the thermal element 8 and extend linearly from the convex portion 5a arranged in the vicinity of the thermal element 8 to the convex portion 5a arranged in the vicinity of the pattern wiring 9. ing. Along with the shape of the elongated positioning hole 7a, a pair of hole-filling resin portions 10 are also arranged on both sides of the thermal element 8 and extend linearly along the pattern wiring 9 from the vicinity of the thermal element 8. ing.

The thermal element 8 is a chip thermistor having terminal electrodes formed at both ends. As the heat sensitive element 8, a flake thermistor element, a thin film thermistor, a pyroelectric element, or the like may be used.
The insulating film 7 is adhered to the bottom portion 5 of the crimp terminal 6 with an adhesive G containing a metal filler.
For example, as the adhesive G, a silver filler-containing high thermal conductive silver adhesive (50 to 95 W/(m·K)) manufactured by Harima Kasei Co., Ltd. can be used.

The pair of lead wires 3 are joined and connected to the pad portions 9a at the other ends of the pair of pattern wirings 9 by soldering, welding or conductive adhesive. Note that the pad portion 9a is formed wider than the other portions in order to connect the lead wire 3. As shown in FIG.

The insulating film 7 is formed in a rectangular shape, for example, from a polyimide resin sheet with a thickness of 7.5 to 125 μm.
One ends of the pair of pattern wirings 9 are connected to terminal electrodes at both ends of the thermal element 8 .
These pair of pattern wirings 9 are patterned with a metal film such as a Cu film, for example.

The crimp terminal 6 has a U-shaped wall portion 11 surrounding the heat-sensitive element portion 2 in plan view. These wall portions 11 surround the thermal element portion 2 from three directions, except for the portion to which the lead wire 3 is connected, and are erected on the peripheral portion of the bottom portion 5 .
The screw mounting portion 4 is provided on the tip side of the bottom surface portion 5 and has a screw mounting hole (not shown) through which a screw can be inserted, as in the conventional example shown in FIG.

To fabricate the temperature sensor 1 of this embodiment, first, as shown in FIG. ) is placed. At this time, as shown in FIG. 3, positioning is performed by inserting the projections 5a into the corresponding positioning holes 7a.

Next, as shown in FIG. 4, a hole-filling resin portion 10 is formed so as to cover the convex portion 5a and fill the positioning hole 7a. At this time, the hole-filling resin portion 10 has a shape elongated according to the elongated positioning hole 7a.
Further, by bonding the end of the lead wire 3 to the pad portion 9a by soldering or the like, the temperature sensor 1 is manufactured as shown in FIG.

As described above, in the temperature sensor 1 of the present embodiment, the bottom surface portion 5 has a plurality of protrusions 5a on the upper surface, and the insulating film 7 is formed at positions corresponding to the plurality of protrusions 5a. The insulating film 7 has a plurality of positioning holes 7a inserted therethrough, and a hole-filling resin portion 10 is formed on the upper surface of the insulating film 7 to cover the convex portions 5a and fill at least the positioning holes 7a. It is positioned by the positioning hole 5a and the positioning hole 7a and is firmly fixed by the hole-filling resin portion 10. As shown in FIG. In addition, the heat of the bottom surface portion 5 is transmitted to the upper surface side of the insulating film 7 provided with the heat sensitive element 8 by the convex portion 5a and the hole-filling resin portion 10, and high thermal responsiveness can be obtained.

Further, since the positioning hole 7a is an elongated hole, the elongated positioning hole 7a is filled with the hole-filling resin portion 10, so that the hole-filling resin portion 10 extends over a wide range of the bottom portion 5. Heat can be induced to the top side.
Furthermore, since the hole-filling resin portion 10 extends from the vicinity of the thermal element 8 along the pattern wiring 9, the hole-filling resin portion 10 can guide the heat on the pattern wiring 9 side to the thermal element 8 side. Thus, higher thermal responsiveness can be obtained, and heat dissipation from the lead wires 3 connected to the pattern wiring 9 can be suppressed. In particular, by adopting the hole-filling resin portion 10 with high thermal conductivity, it is possible to obtain even higher thermal responsiveness and heat radiation suppression effect.

Next, second and third embodiments of the temperature sensor according to the present invention will be described below with reference to FIGS. 5 and 6. FIG. In addition, in the following description of each embodiment, the same reference numerals are given to the same components as those described in the above embodiments, and the description thereof will be omitted.

The difference between the second embodiment and the first embodiment is that only the pattern wiring 9 is formed on the top surface of the insulating film 7 in the first embodiment, whereas the temperature sensor 21 in the second embodiment is formed in a pattern. Then, as shown in FIG. 5, a pattern 27 for heat conduction is formed on the upper surface of the insulating film 7 with a material having a higher thermal conductivity than the insulating film 7 and extends from the hole-filling resin portion 10 to the thermal element 8. There is a point that it has

In the second embodiment, the heat-conducting pattern 27 extends so as to connect the left and right convex portions 5a of the thermal element 8, and the partway thereof extends to directly under the thermal element 8 to form a T-shape. ing.
In order to prevent direct contact between the heat-conducting pattern 27 and the heat-sensitive element 8, the heat-conducting pattern 27 is covered with an insulating coverlay to ensure electrical insulation.
The heat-conducting pattern 27 is patterned, for example, with copper foil in the same manner as the pattern wiring 9 .

As described above, in the temperature sensor 21 of the second embodiment, a pattern is formed on the upper surface of the insulating film 7 with a material having a higher thermal conductivity than the insulating film 7 , and the heat that extends from the hole-filling resin portion 10 to the thermosensitive element 8 is detected. Since the conductive pattern 27 is provided, the highly heat conductive heat conductive pattern 27 serves as a thermal coupling route between the hole-filling resin portion 10 and the thermal element 8, further improving thermal responsiveness.

Next, the difference between the third embodiment and the second embodiment is that in the second embodiment, only the T-shaped heat conduction pattern 27 connecting the pair of convex portions 5a is formed. In the temperature sensor 31 of the third embodiment, as shown in FIG. 6, in addition to the T-shaped heat conduction pattern 27, a pair of heat conduction patterns 37 extending along the pair of pattern wirings 9 are formed. It is a point that is done.

The pair of heat-conducting patterns 37 extends along the pair of pattern wirings 9 from the vicinity of the thermal element 8 . The heat-conducting pattern 37 is pattern-formed with copper foil in the same manner as the heat-conducting pattern 27 .
That is, in the third embodiment, the T-shaped heat-conducting pattern 27 and the pair of heat-conducting patterns 37 extend in a U-shape surrounding the thermal element 8 as a whole.
For this reason, in the third embodiment, the positioning hole 37a is not an elongated hole but a round hole corresponding to the protrusion 5a, and the hole-filling resin portion 30 is formed in a circular or elliptical shape in plan view corresponding to the positioning hole 37a. ing.

As described above, in the temperature sensor 31 of the third embodiment, the heat-conducting pattern 37 extends from the vicinity of the heat-sensitive element 8 along the pattern wiring 9, so that the heat-conducting pattern 37 with high heat conductivity can be used for the pattern wiring. The heat on the side of 9 can be guided to the side of the thermosensitive element 8, so that higher thermal responsiveness can be obtained, and heat dissipation from the lead wires 3 connected to the pattern wiring 9 can be suppressed.
In addition, since the T-shaped heat-conducting pattern 27 and the pair of heat-conducting patterns 37 extend in a U-shape surrounding the heat sensitive element 8, the heat-conducting pattern of the U-shape heats the heat sensitive element. Heat can be efficiently transmitted to the heat-sensitive element 8 from around 8, and higher thermal responsiveness can be obtained.

The technical scope of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.
For example, in the above embodiment, crimp terminals such as so-called round R terminals or Y terminals are used, but the shape of the screw mounting portion may be any other shape as long as the screw mounting portion can be screwed.

DESCRIPTION OF SYMBOLS 1, 21, 31... Temperature sensor, 2, 102... Thermal element part, 3... Lead wire, 4, 104... Screw mounting part, 5, 105... Bottom part, 5a... Protruding part, 6, 106... Crimp terminal, 7 , 107... Insulating film 7a, 37a... Positioning hole 8... Thermosensitive element 9, 109... Pattern wiring 10, 30... Hole-filling resin part 27, 37... Pattern for heat conduction

Claims (7)

a thermal element section;
a pair of lead wires one end of which is connected to the thermal element;
a crimp terminal having a screw mounting portion that can be fixed to a measurement object with a screw and a bottom portion to which the thermal element portion is mounted;
The thermal element portion comprises an insulating film provided on the upper surface of the bottom surface portion, a thermal element provided on the upper surface of the insulating film, one end connected to the thermal element, and the other end connected to a pair of thermal elements. a pair of pattern wiring connected to the lead wire and formed on the upper surface of the insulating film;
The bottom portion has a plurality of protrusions on the top surface,
The insulating film has a plurality of positioning holes formed at positions corresponding to the plurality of protrusions and through which the protrusions are inserted,
A temperature sensor according to claim 1, wherein a hole-filling resin portion is formed on an upper surface of the insulating film to cover the protrusion and to fill at least the positioning hole. The temperature sensor of claim 1, wherein
A heat conducting pattern is formed on an upper surface of the insulating film from a material having a higher thermal conductivity than the insulating film and extends from the hole-filling resin portion to the thermal element. temperature sensor. The temperature sensor of claim 2, wherein
A temperature sensor according to claim 1, wherein the heat-conducting pattern extends along the pattern wiring from the vicinity of the heat-sensitive element. The temperature sensor according to claim 2 or 3,
A temperature sensor, wherein the heat-conducting pattern extends in a U-shape surrounding the heat-sensitive element. In the temperature sensor according to any one of claims 1 to 4,
A temperature sensor, wherein the hole-filling resin portion is made of a material having a higher thermal conductivity than the insulating film. The temperature sensor according to any one of claims 1 to 5,
A temperature sensor, wherein the positioning hole is an elongated hole. The temperature sensor according to any one of claims 1 to 6,
A temperature sensor according to claim 1, wherein said hole-filling resin portion extends along said pattern wiring from the vicinity of said thermosensitive element.

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