Thermal protector

Abstract

Provided is a self-holding thermal protector which is of a non-fixed type in which a thermal response element is not affixed, has a high contact pressure before a reversal operation of the thermal response element, and efficiently holds a state after the reversal operation. A thermal protector (100) is provided with: a fixed plate (10) having a fixed contact (12); a base member (20); a conductive movable plate (40) having, at one end thereof, a movable contact (41) facing the fixed contact; a thermal response element (60) that, when a set operating temperature is exceeded, performs a reverse operation to displace the movable plate, and separates the movable contact, which is in contact with the fixed contact, from the fixed contact; a heating resistor (30); an acting member (70) made of an elastic material; and a fixing member (50). The acting member is provided with: a fixed part (71) which is in surface contact with at least a part of the heating resistor via the fixed part of the movable plate and which is fixed by the base member and the fixed member; and an arm part (72) which is adjacent to the fixed part and has a protruding part which is in pressing contact with the central part of the thermal response element.

Description

Technical Field

[0001] This invention relates to a thermal protector connected to an electrical device and switching the electrical circuit on and off via a thermally responsive element. More specifically, this invention relates to a self-holding thermal protector with a built-in heating resistor that maintains the open state of the contacts by heating the resistor when the contacts are open. Background Technology

[0002] Thermal protectors come in two types: automatic reset type and self-holding type. To prevent the temperature of electrical equipment from rising above a certain value under normal operating conditions, or to activate under abnormal conditions to prevent the temperature from rising above a dangerous level, self-resetting thermal protectors with built-in bimetallic elements are sometimes used. In this type of thermal protector, the bimetallic element reverses its operation at a set operating temperature to open the contacts and disconnect the electrical circuit. Then, when the ambient temperature drops, the bimetallic element reverses its operation again at a set recovery temperature, bringing the contacts together and automatically reconnecting the electrical circuit.

[0003] In the case of an automatic reset type, even if the electrical equipment is in an abnormal state due to a malfunction, the electrical circuit will be automatically reconnected as long as the temperature of the electrical equipment drops. However, in the case of an automatic reset type thermal protector used in motor equipment, since it is unknown when the thermal protector will reset after activation, rotating fans or rotating blades connected to the motor equipment may suddenly start rotating unintentionally.

[0004] To prevent automatic reconnection of the electrical circuit, a self-holding thermal protector is used. A self-holding thermal protector has a built-in heating resistor composed of a PTC element. After the contacts open, as long as the user of the electrical equipment does not disconnect the power, the heating resistor will maintain the open state of the contacts.

[0005] Patent Document 1 describes a method for efficiently transferring the heating resistance of a heating element to a bimetallic component in a self-holding thermal protector. Generally, thermal protectors require increased contact pressure between the movable contact and the fixed contact to stabilize contact resistance, address poor conductivity, and prevent contact disconnection caused by external vibrations. Patent document 2 describes a thermal protector that increases contact pressure by providing an external force-applying member that presses the bimetallic plate toward the movable plate side without causing a large burden on the reversal of the bimetallic plate. Patent document 3 describes a structure configured to increase contact pressure by using the elasticity of the bimetallic member to continuously press the movable plate towards the fixed plate when the temperature is below a set temperature. Patent document 4 describes a method of applying stress to a heat-deformable plate such as a bimetallic part using screws or the like to increase contact pressure. Existing technical documents Patent documents

[0006] Patent Document 1: Japanese Patent No. 3756700 Patent Document 2: Japanese Patent Application Publication No. 2002-184276 Patent Document 3: Japanese Patent No. 2844026 Patent Document 4: Japanese Patent Application Publication No. 62-88232 Summary of the Invention The problem the invention aims to solve

[0007] Thermal protectors are broadly classified into non-fixed types, where the thermal response elements, such as bimetallic components, are not fixed, and fixed types, where a portion of the thermal response element is fixed to another component. Patent documents 1 and 2 relate to non-fixed types, while patent documents 3 and 4 relate to fixed types. The non-fixed type allows for flexibility in specification setting because it only requires pre-producing the component into which the bimetallic part will be installed in the manufacturing process, and then inserting the bimetallic part corresponding to the operating specifications in subsequent processes. Since the bimetallic part has a relatively simple shape, the operating temperature can be freely set, for example, between 10°C and 200°C. Because the contact pressure is typically obtained solely from the elasticity of the movable plate, the contact pressure is approximately 100–200 mN. If the elasticity of the movable plate is increased to increase the contact pressure, the reversing force of the bimetallic part will deteriorate, making proper contact opening and closing difficult. Therefore, a structure like that in Patent Document 2 has been proposed to obtain higher contact pressure.

[0008] On the other hand, the fixed type can increase contact pressure through the bimetallic component. However, in the manufacturing process, the bimetallic component needs to be installed simultaneously with other components, making subsequent changes to the operating specifications difficult. In addition, since a part for fixing the bimetallic component needs to be set in the bimetallic component, it is not easy to set the operating temperature, and the temperature is limited (setting low temperatures such as 10°C and high temperatures such as 200°C is difficult).

[0009] Self-holding thermal protectors require efficient heat transfer from the heating resistor to the bimetallic component after it has reversed its operation. However, if heat is only transferred to a portion of the bimetallic component, the deviation in the reversed shape of the bimetallic component will increase, resulting in an unsuitable reversed state. Due to temperature fluctuations, it will be difficult to maintain the reversed state, i.e., the self-holding state, of the bimetallic component.

[0010] In view of the above situation, the present invention aims to provide a self-holding thermal protector that is a non-fixed type in which the thermal response element is not fixed, the contact pressure of the thermal response element is high before the reverse operation, and the thermal efficiency of the heating resistor can be well transferred to the thermal response element after the reverse operation. Solution for solving the problem

[0011] One embodiment of the present invention relates to a thermal protector comprising: a conductive fixed plate having a fixed contact at one end and a first terminal at the other end; an electrically insulating base member; a conductive movable plate having a movable contact at one end opposite to the fixed contact, and a fixed portion and a second terminal at the other end that are connected to the base member; a thermal response element that reverses operation when a set operating temperature is exceeded, the reversing force of the reversing operation displacing the movable plate and causing the movable contact, which is in contact with the fixed contact, to move away from the fixed contact; a heating resistor disposed between the fixed plate and the movable plate; an actuating member made of an elastic material; and a fixing member comprising: a fixing portion that makes surface contact with at least a portion of the heating resistor via the fixing portion of the movable plate and is fixed by the base member and the fixing member; and an arm portion adjacent to the fixing portion having a protrusion that presses against the central portion of the thermal response element. Invention Effects

[0012] According to the present invention, a self-holding thermal protector can be provided, which is a non-fixed type in which the thermal response element is not fixed, the contact pressure of the thermal response element is high before the reverse operation, and the thermal efficiency of the heating resistor can be well transferred to the thermal response element after the reverse operation. Attached Figure Description

[0013] Figure 1 This is a longitudinal cross-sectional view of the thermal protector according to the first embodiment. Figure 2 yes Figure 1 AA-line cross-section diagram. Figure 3 This is an exploded perspective view of the thermal protector according to the first embodiment. Figure 4 yes Figure 3 The BB line cross-section diagram of the component. Figure 5 This is a longitudinal cross-sectional view of the thermal protector after the bimetallic component of the first embodiment has been reversed. Figure 6 yes Figure 5 CC-line cross-sectional view of the functional components, fixing components, and bimetallic parts. Figure 7 This is a 3D view of the bimetallic part after the inversion process. Figure 8 This is a longitudinal cross-sectional view of the thermal protector involved in the second embodiment. Figure 9 yes Figure 8 DD line cross-section diagram. Figure 10 yes Figure 8 A three-dimensional view of the functional components and fixing components. Figure 11 This is a longitudinal cross-sectional view of the thermal protector after the bimetallic component involved in the second embodiment has been reversed. Figure 12 yes Figure 11 EE line cross-sectional view of the functional components and bimetallic parts. Figure 13 This is a longitudinal cross-sectional view of the thermal protector involved in the third embodiment. Figure 14A It is a three-dimensional diagram of a functional component with a slit. Figure 14B It is a three-dimensional diagram of a functional component with ribs. Detailed Implementation

[0014] A thermal protector according to one embodiment of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below. The aspect ratios of the shapes shown in the drawings are sometimes not actual aspect ratios. The aspect ratios have sometimes been changed for ease of understanding of the shapes in the description.

[0015] <First Embodiment> Figure 1 This is a longitudinal cross-sectional view of the thermal protector 100 according to this embodiment. Figure 2 yes Figure 1 AA-line cross-section diagram, Figure 3 This is an exploded perspective view of thermal protector 100. Figure 4 yes Figure 3 The BB line section diagram of component 70. The thermal protector 100 is a generally rectangular plate-like body. In the accompanying drawings, the x-axis, y-axis, and z-axis represent the long side, width, and thickness directions of the thermal protector 100, respectively. The positive x-axis direction is also referred to as the front, and the negative x-axis direction as the rear. The positive y-axis direction (the direction towards the front of the thermal protector 100 is the left direction) is also referred to as the left direction, and the negative y-axis direction as the right direction. The positive z-axis direction (the direction from the back of the thermal protector 100 to the front) is also referred to as the top, and the negative z-axis direction as the bottom.

[0016] The thermal protector 100 includes a fixed plate 10, a base component 20, a heating resistor 30, a movable plate 40, a bimetallic component 60, an action component 70, and a fixing component 50.

[0017] The fixing plate 10 is made of a flexible metal plate, with an external connection terminal 11 at the rear end and a fixing contact 12 at the top end. A base member 20 made of electrically insulating resin material is fixedly mounted on the fixing plate 10. Figure 3 As shown, the base member 20 has a square hole 21 extending through the center in the thickness direction, and a cuboid heating resistor 30 composed of a PTC (Positive Temperature Coefficient) element is housed in the square hole 21. In addition, a protrusion 22 is formed in the center of the upper surface of the top end of the base member 20, and support pillars 23 are formed on both sides of the upper surface of the rear end in the width direction.

[0018] Above the base member 20, a movable plate 40 formed of a flexible metal plate is disposed. The movable plate 40 includes: a movable contact 41 formed on the lower surface of the top end, which is opposite to the fixed contact 12 along the thickness direction; a clearance hole 42 provided behind the movable contact 41; a tongue 43 provided behind the clearance hole 42; a notch 44 formed on both sides of the rear end in the width direction; and an external connection terminal 45 formed at the rear end.

[0019] The tongue 43 is formed by providing a roughly U-shaped cutout 46 in the center of the movable plate 40. The tongue 43 extends along the long side axis of the movable plate 40, with its base located at the rear and its top located at the front (on the movable contact 41 side). Elongated elastic arms 47 extending along their long sides are formed on both sides of the tongue 43 in the width direction. The elastic arms 47 are bent downward at the rear end of the cutout 46. Therefore, the front half of the movable plate 40, which includes the elastic arms 47, forms an acute angle with respect to the tongue 43. The notch 44 is fitted into the support column 23 of the base member 20.

[0020] A plate-shaped actuating member 70 with elasticity and thermal conductivity is provided on the upper part of the movable plate 40. The actuating member 70 is made of a metal with high thermal conductivity, such as copper alloy, and has a fixing part 71 that is fixed as described later, and an arm part 72 located in front of the fixing part 71. Notches 71a are formed on both sides of the fixing part 71 in the width direction to fit into the support column 23 of the base member 20.

[0021] The arm portion 72 has an upright portion extending upward from the front end of the fixed portion 71 and a main body portion extending forward from the upper end of the upright portion through bending processing at two locations. Figure 4The main body of the arm portion 72 has a bent portion H1 extending in the width direction, which gradually rises from the rear end of the main body portion toward the bent portion H1 and gradually descends from the bent portion H1 toward the front end of the main body portion. At the top end of the main body portion of the arm portion 72, a protrusion 72a is provided that is recessed in the upper surface and protrudes in the lower surface. The shape of the protrusion 72a when viewed from the upper surface and when viewed from the lower surface is not limited to... Figure 3 The circle shown can also be elliptical (not shown). In addition, a hole 72b is provided in the arm 72 from the raised part to the rear end of the main body.

[0022] Furthermore, a metal fixing member 50 is disposed on the upper surface of the fixing portion 71 of the actuating member 70. The notches 51 formed on both sides of the fixing member 50 in the width direction are fitted into the support column 23 of the base member 20. The front end portion 52 of the fixing member 50 protrudes forward from the hole 72b of the actuating member 70.

[0023] By performing a hot riveting process that heats the support column 23 after it is fitted with the notch 44 of the movable plate 40, the notch 71a of the actuating member 70, and the notch 51 of the fixing member 50, and applies pressure to the upper part of the support column 23 to deform the support column 23, the movable plate 40, the actuating member 70, and the fixing member 50 are fixed to the base member 20.

[0024] Therefore, the rear end of the movable plate 40 and the fixing part 71 of the actuating member 70 are held by the lower surface of the fixing member 50 and the upper surface of the rear end of the base member 20. Furthermore, the fixing part 71 of the actuating member 70 makes surface contact with a portion of the upper surface 31 of the heating resistor 30 via the rear end of the movable plate 40. As described above, the front end 52 of the fixing member 50 protrudes forward from the hole 72b of the actuating member 70. The protrusion 22 of the base member 20 protrudes upward from the hole 42 of the movable plate 40.

[0025] A bimetallic member 60, which is a rectangular plate-shaped member and a thermally responsive body, is inserted between the movable plate 40 and the arm 72 of the actuating member 70. The front end of the bimetallic member 60 is engaged with a claw 48 provided at the top of the movable plate 40, and the rear end of the bimetallic member 60 is engaged with the lower surface of the front end 52 of the fixing member 50 protruding forward from the hole 72b. The bimetallic component 60 can be inserted before or after the aforementioned hot riveting process. Inserting the bimetallic component, which corresponds to the operating specifications, after the hot riveting process provides greater flexibility in specification setting. In either case, this thermal protector is non-fixed, and the bimetallic component 60 is not fixed to any other component.

[0026] Due to the elasticity of the movable plate 40 supported by the base member 20, the movable contact 41 is pressed into contact with the fixed contact 12. At this time, the protrusion 22 of the base member 20 enters the clearance hole 42, and the tongue 43 is in contact with the upper electrode surface 31 of the heating resistor 30. Figure 3 (Closely attached)

[0027] When the movable contact 41 of the movable plate 40 and the fixed contact 12 are in the normal state of pressed contact (refer to...) Figure 1 The top of the movable plate 40 is located on the upper electrode surface 31 of the heating resistor 30. Figure 3 The lower position. Furthermore, in this state, the arm 47 of the movable plate 40 is located to the side of the heating resistor 30. The base member 20, due to... Figure 3 As shown, a slope 24 is formed in the front half, the height of which decreases as it goes forward, so it does not contact the arm 47.

[0028] The protrusion 72a of the arm 72 of the actuating member 70 contacts the central portion of the bimetallic member 60 and presses the central portion downward, applying stress to the top of the movable plate 40, thereby further pressing the movable contact 41 against the fixed contact 12. In other words, by providing the actuating member 70, the contact pressure of the bimetallic member before reversing operation is increased. In addition, since the protrusion 72a presses the central portion of the bimetallic member 60, not its periphery, the operating temperature of the bimetallic member 60 is not changed by the pressing of the protrusion 72a.

[0029] In the fixing plate 10, two raised portions 13 are formed below the hole 21 of the base member 20, having a corrugated cross-section when viewed in the width direction. The two raised portions 13 are located adjacent to each other in the long side direction of the fixing plate 10. Parallel slits extending in the long side direction are formed on both sides of the two raised portions 13 in the width direction. The raised portions 13 are formed by stamping the area sandwiched by the two slits into a corrugated shape.

[0030] The height of the lower end of the valley formed between the two raised portions 13 is set to the height of the upper surface of the flat portion of the fixing plate 10 or higher. The raised portions 13 have vertical elasticity, therefore... Figure 1 As shown, it is in elastic contact with the lower electrode surface 32 of the heating resistor 30.

[0031] The raised portion 13 exerts an upward force on the heating resistor 30 through its elasticity, so even if there is an error in the height dimension of the heating resistor 30, the error will be absorbed by the elasticity of the raised portion 13. As a result, the electrical contact between the tongue 43 and the upper electrode 31 of the heating resistor 30, and the electrical contact between the fixing plate 10 and the lower electrode 32 of the heating resistor 30, become stable.

[0032] Furthermore, surface treatments (e.g., plating) can be applied to the contact surfaces of the tongue 43 with the upper electrode surface 31 of the heating resistor 30 and the contact surfaces of the raised portion 13 with the lower electrode surface 32 of the heating resistor 30 to improve electrical contact stability. This further improves the electrical contact stability between the tongue 43 and the fixing plate 10 and the heating resistor 30.

[0033] Other methods besides the surface treatments mentioned above can also be used to improve electrical contact stability. That is, conductive paste can also be placed between the upper electrode surface 31 of the heating resistor 30 and the tongue 43, and between the lower electrode surface 32 of the heating resistor 30 and the fixing plate 10.

[0034] The assembled mechanical elements are inserted into an electrically insulating resin housing C, which is rectangular in shape and has an opening on its rear end face (the end face on the negative x-axis side).

[0035] exist Figure 3 The bent portion H1 of the arm 72, located at the highest position among the inserted components (fixed plate 10, base component 20, heating resistor 30, movable plate 40, bimetallic component 60, actuating component 70, and fixing component 50), is positioned higher than the inner surface of the housing C. Therefore, the inserted component is inserted by pressing the bent portion H1 against the inner surface of the housing C. After insertion, a higher contact pressure is generated. By inserting it into the housing C in this way, the pressure applied to the bimetallic component 60 can be increased. On the other hand, since the pressure applied by the arm 72 before insertion is relatively small, the bimetallic component 60 can be easily inserted.

[0036] The opening of the housing C is sealed with resin or other resin. The wire L1 is connected to the external connection terminal 11 formed at the rear end of the fixed plate 10 by welding or the like, and the wire L2 is connected to the external connection terminal 45 formed at the rear end of the movable plate 40 by welding or the like.

[0037] As an example, when various bimetallic components with operating temperatures set to 50°C to 170°C are installed, the contact pressures become 500 to 1000 mN. Compared to the typical contact pressure of 100 to 200 mN in existing bimetallic non-fixed thermal protectors, this represents a significant increase in contact pressure. Generally, the shape (thickness dimension) of the bimetallic part varies depending on the set operating temperature, but since the protrusion 72a of the actuating member 70 is movable, it is possible to press the central part of the bimetallic part by following its shape.

[0038] <Function> In the thermal protector 100, when the contacts are closed at a relatively low temperature, the load current flows in the order of external connection terminal 11, fixed plate 10, fixed contact 12, movable contact 41, movable plate 40, external connection terminal 45, or in the reverse order. As the temperature of the bimetallic component 60 rises, its radius of curvature changes (increases) and approaches a planar shape from a curved shape. However, following this change, the protrusion 72a of the arm 72 presses down on the bimetallic component 60. As it approaches a planar shape, the deflection of the actuating member 70 decreases, thus reducing the pressure on the bimetallic component 60 and the contact pressure. Because the stress applied to the bimetallic component 60 is reduced, its operating temperature does not change from the design value (the operating temperature measured individually for the bimetallic component before installation).

[0039] When the temperature of the bimetallic component 60 reaches the set operating temperature, the bimetallic component 60 reverses in a snap-action manner, using the protrusion 22 of the base component 20 as a fulcrum. Figure 5 This is a longitudinal cross-sectional view of the thermal protector 100 after the bimetallic component 60 has been reversed. Figure 6 yes Figure 5 CC-line cross-sectional view of functional component 90, fixing component 50, and bimetallic component 60. Figure 7 This is a three-dimensional view of the bimetallic part 60 that has undergone reverse operation. Figure 6 The cross-section of the bimetallic part 60 shown is equivalent to Figure 7 The cross section of the y1-y1 line. For example... Figure 7 As shown, the bimetallic part 60 is bent in the x-axis direction and the y-axis direction, respectively. The movable contact 41 is separated from the fixed contact 12 by the reversing force of the bimetallic member 60, resulting in the electrical circuit being cut off. The protrusion 72a of the arm portion 72 contacts the center of the upper surface of the bimetallic member 60, and the center of the lower surface of the bimetallic member 60 contacts the protrusion 22 of the base member 20. Therefore, the contact of the protrusion 72 of the arm portion 72 will not affect the recovery temperature set for the bimetallic member. like Figure 6 As shown, since the bottom surface of the front end 52 of the fixing member 50 is located on the side of the bimetallic member 60 closer to the bottom surface of the arm 72, and the bimetallic member 60 is curved, the front end 52 of the fixing member 50 and the left and right ends of the arm 72 are in contact with the bimetallic member 60.

[0040] Furthermore, the lower surface of the rear end of the bimetallic piece 60 after reversal abuts against the upper surface of the tip of the tongue 43 of the movable plate 40. This is because, when the movable contact 41 and the fixed contact 12 are in a pressed contact state, the height of the tip of the movable plate 40 is set below the height of the upper electrode surface 31 of the heating resistor 30.

[0041] When the movable contact 41 moves away from the fixed contact 12 through the reversing action of the bimetallic part 60, the heating resistor 30 is energized and heats up through the external connection terminals 11 and 45. The heat is transferred directly to the bimetallic member 60 not only from the tongue 43 of the movable plate 40 and the top of the fixed member 50, but also from the left and right ends of the arm 72 and the protrusion 72a. Since the fixed part 71 of the actuating member 70 makes surface contact with a portion of the upper surface of the heating resistor 30 via one end of the movable plate 40, heat is efficiently transferred to the bimetallic member 60 (especially the rear end). Through the contact between the protrusion 72a of the arm 72 and the center of the bimetallic member 60, heat is efficiently transferred to the front end of the bimetallic member 60. Therefore, the reverse shape deviation of the bimetallic member 60 after reversal is small, resulting in a suitable reverse shape. Furthermore, by fully reversing the bimetallic member, the gap (contact gap) between the fixed contact 12 and the movable contact 41 increases, enabling instantaneous interruption of current. As a result, a stable self-holding state can be maintained compared to the past.

[0042] In addition, such as Figure 6 As shown, the bottom surface of the front end 52 of the fixing member 50 is positioned closer to the bimetallic member 60 than the bottom surface of the arm 72, which also contributes to the widening of the contact gap. This is because the rear end of the bimetallic member 60 descends, the protrusion 22 of the base member 20 becomes a fulcrum, and the front end of the bimetallic member 60 rises. In the self-holding state, the bent portion H1 of the arm 72 can be in contact with the inner surface of the housing or not. However, in the case of non-contact, since heat will not dissipate from the bent portion H1 to the housing, the bimetallic member 60 will be heated more efficiently. When the heating resistor 30 heats up, the heat is transferred to the bimetallic member 60 through its internal space. Furthermore, since a portion of the bimetallic member 60 is in contact with the tongue 43 of the movable plate 40, which is in close contact with the heating resistor 30, the heat from the heating resistor 30 is directly transferred to the bimetallic member 60 through this contact portion. As a result, the reversed state of the bimetallic member 60 is maintained, and the open state of the movable contact 41 continues. That is, self-holding is achieved. Furthermore, when the power switch of the electrical device (not shown) connected to the thermal protector 100 is turned off, the energization to the heating resistor 30 stops, and heating also stops. As a result, the temperature of the bimetallic element 60 decreases. When the temperature of the bimetallic element 60 drops to the set recovery temperature, the bimetallic element 60 performs a reversal operation (recovery operation), such as... Figure 1 As shown, the movable contact 41 will re-engage with the fixed contact 12.

[0043] Alternatively, a protrusion that contacts the bimetallic member 60 after inversion can be provided on the upper surface of the tongue 43 of the movable plate 40. In this case, the position and shape of the heating resistor 30 and the tongue 43 can be set so that the protrusion contacts a part of the bimetallic member 60 slightly behind the center. Thus, when the tongue 43 is provided with a protrusion, the heat from the heating resistor 30 will be transferred to the bimetallic part 60 more efficiently because the bimetallic part 60 is in contact with the protrusion. However, regardless of whether a protrusion is provided on the tongue 43, the bimetallic part 60 is reversed using the protrusion 22 of the base member 20 as a fulcrum. After reversal, the central portion of the bimetallic part 60 is clamped by the protrusion 22 and the protrusion 72a of the actuating member 70. Stress is applied to the bimetallic part only from the claw 48 provided at the top of the movable plate 40. Therefore, it is possible to prevent the recovery temperature of the bimetallic part 60 from changing significantly from the design value (the recovery temperature measured separately for the bimetallic part before it is installed).

[0044] <Second Implementation> Figure 8 This is a longitudinal cross-sectional view of the thermal protector 200 according to this embodiment. Figure 9 yes Figure 8 DD line cross-section diagram, Figure 10 It is a three-dimensional diagram of the functional and fixing components. Additionally, Figure 11 This is a longitudinal cross-sectional view of a bimetallic thermal protector 200 that operates in reverse. Figure 12 yes Figure 11 EE line cross-sectional view of the functional components and bimetallic parts. Apart from the functional components and fixing components, it has the same configuration as the thermal protector 100 according to the first embodiment. Unlike the first embodiment, the actuating member 70a does not have a hole 72b. Furthermore, the fixing part 50a does not have the front end portion 52 that protrudes forward through the hole 72 as in the first embodiment. In order to suppress the increase in elastic force of the arm 72 of the action member 70a caused by the absence of the hole 72b, the width dimension of the arm 72 can be made smaller than that in the first embodiment. In addition, the actuating member 70a has a bent portion H2 that corresponds to the bent portion H1 of the actuating member 70. Similar to the first embodiment, the bimetallic member 60 is pressed by the bending portion H2 of the arm portion 72 of the actuating member 70a contacting the inner surface of the electrically insulating resin housing C, and the protrusion 72a of the arm portion 72 contacting the central portion of the bimetallic member 60, thereby applying stress to the top end of the movable plate 40 and increasing the contact pressure. As mentioned above, since no hole 72 is provided in the arm portion 72 of the actuating member 70a, the heat from the heating resistor after the contact is broken is further efficiently transferred to the bimetallic element. Because the end of the bimetallic element and the arm... Figure 12 As shown, the bimetallic component makes contact with the protrusion of the arm, and the heat generated is transferred to the other end of the bimetallic component. This results in minimal deviation in the bimetallic component's reversal shape, achieving a suitable reversal shape. Furthermore, by fully reversing the bimetallic component, the contact gap increases, enabling instantaneous interruption of the current. As a result, a stable self-holding state can be maintained compared to the past.

[0045] <Third Implementation> exist Figure 13 The figure shows a longitudinal cross-sectional view of a thermal protector according to one embodiment. Except that the bent portion H3 of the arm 72 of the actuating member 70b does not contact the inner surface of the electrically insulating resin housing C, it is the same as the configuration of the second embodiment. In the first and second embodiments, the contact pressure is increased by bringing the bent portion of the arm into contact with the inner surface of the housing C. In this embodiment, the rigidity of the actuating member 70b is adjusted by changing its material, thickness, width, bending position, bending angle, etc., so that the contact pressure is increased in a way that a portion of the arm of the actuating member 70b does not contact the inner surface of the housing. able to Figure 14A As shown, two slits 72s in the long side direction are provided in the working member 70b to reduce the rigidity of the arm. Or, can be like Figure 14B As shown, the protrusion 72r of the working member 70c is provided to enhance the rigidity of the arm. In either case, by ensuring that the bent portion H3 of the arm does not contact the inner surface of the housing after the contact is disconnected, the heat from the heating resistor will not dissipate from the bent portion H3 to the housing C, thus ensuring efficient heat transfer from the heating resistor to the bimetallic element. Furthermore, by fully reversing the bimetallic element, the contact gap increases, allowing for instantaneous current interruption. As a result, a stable self-holding state can be maintained compared to previous methods.

[0046] As described above, according to the above embodiments, a self-holding thermal protector can be provided. This self-holding thermal protector is a non-fixed type with a degree of freedom in specification setting during the production process. The contact pressure before reverse operation is higher than before, and after reverse operation, it can efficiently transfer the heat of the heating resistor to the bimetallic part.

[0047] Regarding the implementation methods described above, the following notes are disclosed. [Postscript 1] A thermal protector, comprising: A conductive fixing plate having a fixing contact at one end and a first terminal at the other end; Electrically insulating substrate components; A conductive movable plate has a movable contact at one end opposite to the fixed contact, and a fixing part and a second terminal at the other end that are fixed to the base member. The thermal response element reverses its operation when the set operating temperature is exceeded. The reversing force of this reversing operation causes the movable plate to shift, thereby causing the movable contact, which is in contact with the fixed contact, to move away from the fixed contact. A heating resistor is disposed between the fixed plate and the movable plate; The functional component is made of an elastic material; and Fixed components, The functional component includes: A fixing part, which makes surface contact with at least a portion of the heating resistor via the fixing part of the movable plate, is fixed by the base member and the fixing member; and The arm portion, which is adjacent to the fixing portion, has a protrusion that presses into contact with the central portion of the thermal response element. [Postscript 2] According to the thermal protector described in Appendix 1, wherein, During the period when the thermal response element operates in reverse and the heating element generates heat due to the applied voltage, the reverse operation of the thermal response element is maintained. The arm portion contacts the peripheral portion of the thermal response element. The protrusion is pressed into contact with the central portion of the thermal response element. [Postscript 3] According to the thermal protector described in Appendix 1, wherein, During the heating process before the thermal response element operates at low temperature or reverses, a portion of the arm contacts the inner surface of the housing of the thermal protector. [Postscript 4] According to the thermal protector described in Appendix 2, wherein, A hole is formed in the arm portion, and the front end of the fixing member passes through the hole and protrudes. The bottom surface of the front end is located on the side of the thermal response element closer to the lower surface around the hole of the arm, and the front end is in contact with the thermal response element.

[0048] The embodiments of the present invention have been described above, but the present invention is not limited to the described embodiments, and various modifications and alterations can be made based on the technical concept of the present invention. Explanation of reference numerals in the attached figures

[0049] 100, 200, 300 thermal protectors 10 Fixing Plate 11 External connection terminals 12 Fixed Contacts 20. Base components 21 holes 22. Protrusion 23 pillars 30 Heating resistor 40 Movable Plate 41 Movable contact 43 Tongue slices 45 External connection terminals 46 Incisions 50 Fixed components 60 Bimetallic parts 70 Functional components.

Claims

1. A thermal protector, characterized in that, have: A conductive fixing plate having a fixing contact at one end and a first terminal at the other end; Electrically insulating substrate components; A conductive movable plate has a movable contact at one end opposite to the fixed contact, and a fixing part and a second terminal at the other end that are fixed to the base member. The thermal response element reverses its operation when the set operating temperature is exceeded. The reversing force of this reversing operation causes the movable plate to shift, thereby causing the movable contact, which is in contact with the fixed contact, to move away from the fixed contact. A heating resistor is disposed between the fixed plate and the movable plate; The functional component is made of an elastic material; and Fixed components, The functional component includes: A fixing part, which makes surface contact with at least a portion of the heating resistor via the fixing part of the movable plate, is fixed by the base member and the fixing member; and The arm portion, which is adjacent to the fixing portion, has a protrusion that presses into contact with the central portion of the thermal response element.

2. The thermal protector according to claim 1, wherein, During the period when the thermal response element operates in reverse and the heating element generates heat due to the applied voltage, the reverse operation of the thermal response element is maintained. The arm portion contacts the peripheral portion of the thermal response element. The protrusion is pressed into contact with the central portion of the thermal response element.

3. The thermal protector according to claim 1, wherein, During the heating process before the thermal response element operates at low temperature or reverses, a portion of the arm contacts the inner surface of the housing of the thermal protector.

4. The thermal protector according to claim 2, wherein, A hole is formed in the arm portion, and the front end of the fixing member passes through the hole and protrudes. The bottom surface of the front end is located on the side of the thermal response element closer to the lower surface around the hole of the arm, and the front end is in contact with the thermal response element.

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