Thermal protector

Abstract

The present invention provides a thermal protector which suppresses the degree of complexity of parts machining. A thermal protector 100 is provided with a first terminal section 110 and a second terminal section 120 which are provided to both ends in a lengthwise direction and are connected to an external circuit, an insulation block section 3 which holds the first terminal section and the second terminal section, an affixed contact 113 and a mobile contact 41 which can come into contact with each other, a mobile plate 4 in which the mobile contact is provided to a tip section, and a bimetal 5 which engages the mobile plate, wherein: the first terminal section and the second terminal section each have a main body section, an extension section, and a slit S; the main body section 111 of the first terminal section and the main body section 121 of the second terminal section are in a first plane; an affixed contact support section of the extension section 112 and a mobile plate support section of the extension section 122 are in a second plane; and an angle formed by the first plane and the second plane is an acute angle.

Description

Technical Field

[0001] The present invention relates to a thermal protector that opens and closes an electric circuit to prevent overheating of an electric product.

Background Art

[0002] In electric products that generate hot air, such as hair dryers and fan heaters, thermal protectors are used to prevent overheating due to blockage of the outlet or inlet or a decrease in the speed of the motor. As an example of a thermal protector, a bimetal type thermal protector is described in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The thermal protector described in Patent Document 1 has a bent portion so that an external force does not affect the region sandwiched between two insulating block portions. This bent portion is formed by two-stage bending in the press working of a metal plate after resin molding. Therefore, this two-stage bending has a relatively high complexity in component processing.

[0005] In view of such a situation, an object of the present invention is to provide a thermal protector with reduced complexity in component processing.

Means for Solving the Problems

[0006] The thermal protector according to the present invention includes a first terminal portion and a second terminal portion provided at both ends in the longitudinal direction and connected to an external circuit, an insulating block portion that holds the first terminal portion and the second terminal portion, a fixed contact and a movable contact that can contact each other, a movable plate provided with the movable contact at the tip, and a bimetal engaged with the movable plate. Each of the first terminal portion and the second terminal portion has a main body portion, an extension portion, and a slit extending in the width direction of the thermal protector between the main body portion and the extension portion. The fixed contact is provided at a fixed contact support portion of the extension portion of the first terminal portion, a base end portion of the movable plate is fixed to a movable plate support portion of the extension portion of the second terminal portion, the main body portion of the first terminal portion and the main body portion of the second terminal portion are on a first plane, the fixed contact support portion and the movable plate support portion are on a second plane, and an angle formed between the first plane and the second plane is an acute angle.

Brief Description of the Drawings

[0007]

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Embodiments for Carrying Out the Invention

[0008] Hereinafter, the present invention will be described based on the illustrated embodiments. However, the present invention is not limited to the embodiments described below.

[0009] [First Embodiment] Figs. 1 to 4 show a thermal protector 100 which is an elongated circuit component. The thermal protector 100 is mounted on a hair dryer or the like which is one of the electrical products that generate hot air. The thermal protector 100 includes a first terminal portion 110 and a second terminal portion 120 provided at both longitudinal ends. Both terminal portions are connected to an electrical circuit (an external circuit as seen from the thermal protector 100) such as a hair dryer. As an example, the dimension in the longitudinal direction of the thermal protector 100 is about 3 cm to 4 cm.

[0010] An insulating plate 9 is provided in the cylindrical case CS of the hair dryer. This insulating plate 9 is formed by engaging cut portions formed in opposite directions along the length direction at the central portion in the width direction of two mica plates 9a and 9b, and is cross-shaped as a whole. The insulating plate 9 is arranged in the case CS such that the intersection portion 9c of the two mica plates 9a and 9b is parallel to the axial direction of the case CS. A nichrome wire 9d is spirally wound around the outer periphery of the insulating plate 9. The axis of this spiral is parallel to the axis of the case CS. The direction of the hot air flow inside the case CS is indicated by an arrow H.

[0011] The thermal protector 100 is arranged parallel to the axial direction of the case CS in the vicinity of the intersection portion 9c of the insulating plate 9 such that the first terminal portion 110 is on the leeward side of the hot air and the second terminal portion 120 is on the windward side of the hot air. Note that the portion near the intersection portion 9c of the insulating plate 9 is also called the corner portion of the insulating plate 9.

[0012] The first terminal portion 110 and the second terminal portion 120 have a substantially symmetric structure with a line passing through the center of the thermal protector 100 and orthogonal to the longitudinal direction of the thermal protector 100 as the axis of symmetry. First, the second terminal portion 120 will be described.

[0013] The second terminal portion 120 is made by processing a metal flat plate. The second terminal portion 120 includes a main body portion 121 on the outer side in the longitudinal direction, an extension portion 122 on the inner side in the longitudinal direction, and a slit S. The slit S is formed to extend in the width direction from the end portion on the corner portion side of the insulating plate 9 among both end portions in the width direction of the second terminal portion 120 between the main body portion 121 and the extension portion 122.

[0014] The first terminal portion 110 is the same as the second terminal portion 120. That is, the first terminal portion 110 is also made by processing a metal flat plate. The first terminal portion 110 includes a main body portion 111 on the outer side in the longitudinal direction, an extension portion 112 on the inner side in the longitudinal direction, and a slit S. The slit S is formed to extend in the width direction from the end portion on the corner portion side of the insulating plate 9 among both end portions in the width direction of the first terminal portion 110 between the main body portion 111 and the extension portion 112.

[0015] In the first terminal portion 110, with a line parallel to the longitudinal direction of the thermal protector 100 passing through the tip portion Sa of the slit S as a reference, the main body portion 111 is bent downward with respect to the extension portion 112. Also, in the second terminal portion 120, with a line parallel to the longitudinal direction of the thermal protector 100 passing through the tip portion Sa of the slit S as a reference, the main body portion 121 is bent downward with respect to the extension portion 122. Thus, the first terminal portion 110 and the second terminal portion 120 are subjected to bending processing by a press machine.

[0016] The main body 111 of the first terminal portion 110 and the main body 121 of the second terminal portion 120 are on the first plane. On the other hand, the extension portion 112 of the first terminal portion 110 and the extension portion 122 of the second terminal portion 120 are on the second plane. The angle formed by the first plane and the second plane is an acute angle. The angle of this angle is preferably in the range of 30 degrees to 60 degrees, and more preferably 45 degrees. Also, the intersection line of the first plane and the second plane is parallel to the longitudinal direction of the thermal protector 100.

[0017] The inner end in the longitudinal direction of the extension portion 112 of the first terminal portion 110 and the inner end in the longitudinal direction of the extension portion 122 of the second terminal portion 120 are held by the resin insulating block portion 3. A fixed contact 113 is provided on the upper surface of the extension portion 112 of the first terminal portion 110 (the surface opposite to the mounting surface to the insulating plate 9). That is, the extension portion 112 is also a fixed contact support portion.

[0018] The thermal protector 100 further includes a movable plate 4 that has conductivity and is elastically deformable. The base end portion of the movable plate 4 is fixed to the extension portion 122 of the second terminal portion 120. That is, the extension portion 122 is also a movable plate support portion. A movable contact 41 that contacts the fixed contact 113 during normal times when no abnormality occurs in the hair dryer is provided at the tip of the movable plate 4.

[0019] In the movable plate 4, a bimetal 5 is disposed on the upper surface of the central portion between the base end portion and the tip portion. The bimetal 5 is engaged with the movable plate 4 by four claw portions 4a to 4d provided at both ends in the longitudinal direction and both ends in the width direction of the central portion of the movable plate 4. When the ambient temperature of the thermal protector 100 is below a predetermined temperature, the bimetal 5 is warped convexly upward, and the movable contact 41 is in contact with the fixed contact 113 by the elastic force of the elastically deformable movable plate 4.

[0020] When the peripheral temperature exceeds the predetermined temperature due to abnormal heat generation of the hair dryer caused by overload or the like, the bimetal 5 reverses to be convex downward. When the bimetal 5 reverses, the tip of the movable plate 4 is lifted upward by the restoring force of the bimetal 5. As a result, the movable contact 41 separates from the fixed contact 113, and the power supply to the hair dryer stops.

[0021] An example of the manufacturing process of the thermal protector 100 will be described below. In the first step, a punching process is performed on a flat metal material. In the second step, the fixed contact 113 is attached. At this time, the central portion between the portion that becomes the first terminal portion 110 and the portion that becomes the second terminal portion 120 is held by a frame held by the carrier portion. In the third step, bending processes are performed on the portion that becomes the first terminal portion 110 and the portion that becomes the second terminal portion 120. At this time, the bent portion is also held by the frame. The bending lines are preferably on the same straight line, which will be described later. The processing is sequentially performed with a mold. Note that the first to third steps are press steps. In the fourth step (forming step), the insulating block portion 3 is injection-molded to integrate the first terminal portion 110 and the second terminal portion 120. The molded portion is held by the frame. In the fifth step, the holding portion by the frame that has been fixing the insulating block portion 3 is cut. In the sixth step, the movable plate 4 mounted with the bimetal 5 is fixed by welding. In the seventh step, the thermal protector body is separated from the carrier portion. Note that the fifth to seventh steps are assembly steps.

[0022] The fixed contact 113 is fixed at a predetermined position by resistance welding or caulking. The movable plate 4 is fixed to the extension 122 of the second terminal portion 120 after the insulation block portion 3 is molded. The fixing method at this time may be resistance welding, caulking, or a combination thereof, similar to the fixed contact 113. The bimetal 5 is mounted on the movable plate 4, but the bimetal 5 may be mounted on the movable plate 4 before fixing.

[0023] Claw portions (reference numerals 4a and 4b), which serve as acting points when the bimetal 5 drives the movable plate 4, are provided at both longitudinal ends of the central portion between the proximal end portion and the distal end portion of the movable plate 4. The bimetal 5 is not fixed to one of the claw portions. In the other claw portion, the bimetal 5 abuts against the back surface of the claw portion at the moment when the bending direction of the bimetal 5 is reversed, and the movable plate 4 is driven. Then, when the cantilevered movable plate 4 is lifted, the contact is opened and the current is cut off.

[0024] According to the above embodiments, the following effects can be obtained. (1) The inclination of the fixed contact support portion and the movable plate support portion at a predetermined angle with respect to the mounting surface of the thermal protector 100 is realized by bending. The two-stage bending as in the prior art is unnecessary in this embodiment. That is, the complexity of component processing and the complexity of the structure can be reduced. (2) Conventionally, when the bimetal is disposed at an inclination with respect to the mounting surface of the thermal protector, the 90-degree bending process was performed twice. In contrast, in this embodiment, only one bending is required, and the influence of the bending process can be reduced. (3) By disposing the bimetal at an inclination with respect to the mounting surface of the thermal protector, the thermal protector can be installed at the corner portion of the insulating plate (the radial center portion of the heater unit) that is farthest from the heater wire. In a heater unit, generally, the air volume at the radial center portion is smaller than the air volume on the outside. Therefore, during normal use of the electrical product equipped with the thermal protector, it is difficult for the thermal protector to sense the heat of the heater, while it can quickly sense an abnormality when the electrical product is abnormal such as a decrease in wind speed.

[0025] When many bimetal thermal protectors operate, the tip of the bimetal on the side where the movable contact is provided warps upward. Therefore, in a heater unit with a relatively small body diameter such as a hair dryer, ensuring the insulation distance between the movable contact and the heater wire during operation becomes an issue. One solution to this issue is to arrange the bimetal inclined with respect to the thermal protector mounting surface and install the thermal protector at the corner of the insulating plate farthest from the heater wire, as described in (3) above. That is, the thermal protector is installed at approximately the center of the heater unit.

[0026] [Second Embodiment] The thermal protector 200 is shown in FIGS. 5 to 7. The same elements as those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

[0027] The second terminal portion 220 includes a main body portion 221 and an extension portion 222. The extension portion 222 of the second terminal portion 220 has an upright portion 222a and a movable plate support portion 222b. The upright portion 222a is on a third plane that is orthogonal to the first plane and parallel to the longitudinal direction of the thermal protector 200. The base of the upright portion 222a is in contact with the tip portion Sa of the slit S, and the movable plate support portion 222b is connected to the top of the upright portion 222a.

[0028] The same applies to the extension portion 212 of the first terminal portion 210. That is, the first terminal portion 210 includes a main body portion 211 and an extension portion 212. The extension portion 212 of the first terminal portion 210 has an upright portion 212a and a fixed contact support portion 212b. The upright portion 212a is on the third plane. The base of the upright portion 212a is in contact with the tip portion Sa of the slit S, and the fixed contact support portion 212b is connected to the top of the upright portion 212a.

[0029] In manufacturing, the standing portion is formed by a 90-degree bending process, and a 45-degree bending process is performed at the top of the standing portion. As a result, the extension portions of the respective terminal portions are inclined at a predetermined angle with respect to the main body portion. These two bends can be performed at once in the press working process. That is, two bends can be performed with the same man-hour as one bend. According to this processing, a 90-degree bending process can be performed at the center in the width direction of each terminal portion. In addition, in the first terminal portion 210 and the second terminal portion 220, a second slit S2 may be provided inside the longitudinal direction from the slit S. The second slit S2 is formed so as to extend in the width direction from the end portion on the side opposite to the corner portion side of the insulating plate 9 among both end portions in the width direction of the terminal portion between the main body portion and the extension portion. The second slit S2 is provided so that the tip end portion of the second slit S2 is located on a line extending in the longitudinal direction of the thermal protector 200 passing through the tops of the standing portions 212a and 222a. By providing such a second slit S2, it is possible to sufficiently secure the necessary width for the current to the fixed contact support portion 212b and the movable plate support portion 222b.

[0030] [Third Embodiment] FIG. 8 shows a thermal protector 300. The same elements as those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted. Air guide plates 310 and 320 are provided in the vicinity of the slit S of the first terminal portion 110 and in the vicinity of the slit S of the second terminal portion 120, respectively. Both air guide plates are resin plates having an extension in the width direction and the vertical direction of the thermal protector 300. The dimensions in the width direction and the height direction of both air guide plates are determined so that a fixed contact (not shown in FIG. 8; reference numeral 113 in FIG. 2), a movable contact 41, a movable plate 4, and a bimetal 5 are arranged in the region between both air guide plates. The thickness (dimension in the longitudinal direction) of both air guide plates is not particularly restricted, and about 1 mm is sufficient. Both air guide plates can be provided integrally with an insulating block portion (not shown in FIG. 8; reference numeral 3 in FIG. 2).

[0031] According to this embodiment, when the thermal protector 300 is viewed along the wind direction H, the switch mechanism portion (fixed contact 113, movable contact 41, movable plate 4, bimetal 5) will be hidden by the air guiding plate. Therefore, the flow of the hot air is adjusted by the air guiding plate so that the hot air does not directly hit the switch mechanism portion. That is, the possibility of the thermal protector 300 malfunctioning when the electrical product is in the normal state is reduced.

[0032] [Fourth Embodiment] The thermal protector 400 is shown in FIG. 9. This thermal protector 400 includes air guiding plates 410 and 420. Both air guiding plates are provided so as to enclose a slit (not shown in FIG. 9, reference symbol S in FIG. 8). Since the main body portion and the extension portion of the terminal portion are integrally constrained by the air guiding plates, the strength is improved.

[0033] [Fifth Embodiment] The thermal protector 500 is shown in FIG. 10. An air guiding plate 510 is provided on the first terminal portion 110 so as to enclose the slit S. A cut portion 511 is formed in this air guiding plate 510. There may be a plurality of cut portions. The cut portion preferably has a depth equal to the upper surface of the extension portion of the terminal portion and a width equal to the thickness of the air guiding plate 510.

[0034] According to this embodiment, the hot air flows as shown by the arrow Ha from around the contact toward the cut portion 511. When the current is cut off, the arc generated between the fixed contact (not shown in FIG. 10, reference symbol 113 in FIG. 2) and the movable contact 41 is induced toward the cut portion 511 by this hot air. That is, the possibility of the components around the thermal protector 500 being damaged by the arc can be reduced.

[0035] Incidentally, in electrical products that combine a heater section using a nichrome wire and a blower section using a motor, such as a hair dryer or a hot air hair curler, in recent years, due to requirements such as higher output of heaters, increased air volume and air pressure, and designability, the difficulty of setting the thermal protector is increasing. During normal use, the thermal protector should not operate, and there is an increasing need for it to operate immediately in an abnormal state to cut off the current. Also, since the thermal protector cuts off the current by a switch operation, the generation of arcs during cutoff and the change in insulation distance due to the upward warping of the movable plate after cutoff are also related to the increasing difficulty in electrical safety design.

[0036] The above-described embodiments are for solving such problems. By tilting the switch mechanism part with respect to the mounting surface of the thermal protector, the thermal protector can be arranged at the corner part of an insulating plate formed by combining two mica plates at 90 degrees. For this reason, when the cylindrical heater unit is viewed in the axial direction, the thermal protector can be assembled at the position farthest from the heater wire. As a result, the mica plates are positioned on both sides in the width direction of the switch mechanism part. Also, in the case of a propeller fan, the wind speed at the center part is low due to the rotation of the motor, and the wind speed becomes high near the outer peripheral part where the heater wire is attached. As a result, during normal operation, the hot air flows near the outer periphery of the heater where the heater wires are concentrated, and the central part where the thermal protector is arranged is less affected by heat.

[0037] When an electrical appliance malfunctions, if the air volume decreases due to the distance between the hot air outlet side and the object becoming extremely close, the suction port becoming blocked by dust, or the motor speed decreasing, etc., not only does the discharge temperature increase, but heat also begins to accumulate inside the heater unit. When the limit is exceeded, the thermal protector operates and the heater current is cut off. At this time, an arc is generated between the contacts. With the recent increase in output power, since a large current exceeding 10 amperes is cut off, the influence of the arc becomes greater. Depending on the mounting state of the thermal protector, there may be an accident where the arc is blown by a strong wind and discharges to the nearby nichrome wire. As a result, problems such as the nichrome wire being blown out and the movable plate of the thermal protector being damaged may occur.

[0038] According to each of the above embodiments, in a heater in which a nichrome wire is wound in a coil shape, a thermal protector can be attached at the position farthest from the nichrome wire, and mica plates exist as walls on both sides. Therefore, it becomes difficult for the arc at the time of interruption to jump in the width direction. Since the wind also flows along the mica plate, the arc tends to flow along the wind. By providing a cut portion in the air guiding plate near the contact point like the thermal protector 500, a path for the arc to escape is provided, and it becomes possible to safely control the arc.

[0039] The thermal protector in each of the above embodiments can also be mounted on electrical appliances other than hair dryers. For example, it may be mounted on an electric fan heater or a popcorn machine.

[0040] When assembling the movable plate, an oval guide portion 122a can be provided on the extension portion 122 of the second terminal portion 120 (FIG. 2). A hole portion is provided at the base end portion of the movable plate 4 so as to correspond to this guide portion 122a, and this hole portion is engaged with the guide portion. After performing resistance welding, the upper part of this guide can also be crushed and used as a presser for the movable plate 4.

[0041] That is, an oval guide portion for positioning the movable plate 4 is provided on the movable plate support portion of the extension portion 122 of the second terminal portion 120. This guide portion can be provided parallel to the longitudinal direction of the thermal protector. The length of the guide portion can be three times or more the width.

[0042] In addition, the manufacturing of the thermal protector will be described. When producing by connecting parts, as shown in FIG. 11, connection is made by the carrier portion CR outside each terminal portion for continuous production. It is preferable for stable production that the surface of this carrier portion CR is the same surface as the extension portion of each terminal portion. Bending with a predetermined angle is also required at the connection portion between the carrier and each terminal portion. The bending by cutting and bending at a total of four predetermined angles is preferably performed on the same line L in order to suppress distortion.

[0043] Regarding the embodiments described so far, the following supplementary notes are disclosed. [Supplementary Note 1] A first terminal portion and a second terminal portion provided at both longitudinal ends and connected to an external circuit, An insulating block portion that holds the first terminal portion and the second terminal portion, A fixed contact and a movable contact that can contact each other, A movable plate provided with the movable contact at its tip, A bimetal engaged with the movable plate A thermal protector comprising: Each of the first terminal portion and the second terminal portion has a main body portion, an extension portion, and a slit extending in the width direction of the thermal protector between the main body portion and the extension portion, The fixed contact is provided at the fixed contact support portion of the extension portion of the first terminal portion, The base end portion of the movable plate is fixed to the movable plate support portion of the extension portion of the second terminal portion, The main body portion of the first terminal portion and the main body portion of the second terminal portion are on a first plane, The fixed contact support portion and the movable plate support portion are on a second plane, The angle formed by the first plane and the second plane is an acute angle. Thermal protector.

[0044] [Appendix 2] Each of the extension portions of the first terminal portion and the extension portion of the second terminal portion further has an upright portion, and the upright portion is on a third plane orthogonal to the first plane. In the extension portion of the first terminal portion, the base portion of the upright portion is in contact with the tip portion of the slit, and the fixed contact support portion is connected to the top portion of the upright portion. In the extension portion of the second terminal portion, the base portion of the upright portion is in contact with the tip portion of the slit, and the movable plate support portion is connected to the top portion of the upright portion. The thermal protector according to Appendix 1.

[0045] [Appendix 3] Further provided with a resin air guide plate provided near the slit of the first terminal portion and near the slit of the second terminal portion, and having an extension in the width direction and the vertical direction of the thermal protector. The fixed contact, the movable contact, the movable plate, and the bimetal are arranged in a region sandwiched between the two air guide plates. The thermal protector according to Appendix 1 or 2.

[0046] [Appendix 4] The thermal protector according to Appendix 3, wherein the air guide plate is provided so as to enclose the slit.

[0047] [Appendix 5] The thermal protector according to Appendix 3 or 4, wherein a cut portion is formed in at least one of the two air guide plates.

[0048] [Appendix 6] The thermal protector according to any one of Appendices 1 to 5, wherein the angle formed by the first plane and the second plane is in the range of 30 degrees to 60 degrees.

[0049] [Appendix 7] An oval guide portion for positioning the movable plate is provided on the movable plate support portion of the extension portion of the second terminal portion, and the length of the guide portion is three times or more the width. The thermal protector according to any one of appendices 1 to 6.

[0050] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the described embodiments, and various modifications and changes are possible based on the technical idea of the present invention.

Explanation of reference numerals

[0051] 100, 200, 300, 400, 500 Thermal protector 110 First terminal portion 111 Main body portion 112 Extension portion 113 Fixed contact 120 Second terminal portion 121 Main body portion 122 Extension portion 4 Movable plate 41 Movable contact 5 Bimetal S Slit H Wind direction

Claims

1. A thermal protector comprising: a first terminal portion and a second terminal portion provided at both longitudinal ends and connected to an external circuit; an insulating block portion that holds the first terminal portion and the second terminal portion; a fixed contact and a movable contact that can contact each other; a movable plate provided with the movable contact at its tip; a bimetal engaged with the movable plate, wherein each of the first terminal portion and the second terminal portion has a main body portion, an extension portion, and a slit extending in the width direction of the thermal protector between the main body portion and the extension portion; the fixed contact is provided at a fixed contact support portion of the extension portion of the first terminal portion; a base end portion of the movable plate is fixed to a movable plate support portion of the extension portion of the second terminal portion; the main body portion of the first terminal portion and the main body portion of the second terminal portion are on a first plane; the fixed contact support portion and the movable plate support portion are on a second plane; and an angle formed between the first plane and the second plane is an acute angle. Thermal protector.

2. Each of the extension portion of the first terminal portion and the extension portion of the second terminal portion further has an upright portion, and the upright portion is on a third plane perpendicular to the first plane; in the extension portion of the first terminal portion, a base portion of the upright portion contacts a tip portion of the slit; the fixed contact support portion is connected to a top portion of the upright portion; in the extension portion of the second terminal portion, a base portion of the upright portion contacts a tip portion of the slit; and the movable plate support portion is connected to a top portion of the upright portion. The thermal protector according to claim 1.

3. The thermal protector further includes resin-made air guiding plates provided near the slit of the first terminal portion and near the slit of the second terminal portion, and having an extension in the width direction and the vertical direction of the thermal protector; the fixed contact, the movable contact, the movable plate, and the bimetal are arranged in a region sandwiched between the two air guiding plates. The thermal protector according to claim 1 or 2.

4. The thermal protector according to claim 3, wherein the air guiding plate is provided so as to enclose the slit.

5. The thermal protector according to claim 3 or 4, wherein a cut portion is formed in at least one of the two air guiding plates.

6. The thermal protector according to any one of claims 1 to 5, wherein an angle of the angle formed between the first plane and the second plane is in a range of 30 degrees to 60 degrees.

7. ​ The thermal protector according to any one of claims 1 to 6, wherein an oval guide portion for positioning the movable plate is provided on the movable plate support portion of the extension portion of the second terminal portion, and the length of the guide portion is three times or more the width.

Images