Temperature switch

Abstract

Provided is a non-automatic reset temperature switch having a reduced likelihood of being reset by external force despite the ambient temperature not having dropped to an extremely low temperature after activation.　A temperature switch (100) comprises: a fixed contact (123); a thermally responsive element (140) having a curved shape and of which the shape inverts at a predetermined temperature; and a movable plate (130) made of metal and having elasticity, and being provided with a movable contact (123), which is in contact with the fixed contact, and locking parts (131, 132) on which the thermally responsive element is locked. When the shape of the thermally responsive element has inverted, the movable plate on which the thermally responsive element is locked warps in a predetermined direction, the movable contact separates from the fixed contact, and a tongue piece (135) formed on the movable plate protrudes in the opposite direction to the predetermined direction.

Description

Temperature switch

[0001] The present invention relates to a non-automatic reset type temperature switch.

[0002] Patent Document 1 describes a thermal protector equipped with a bimetal, which reverses its curved shape when it reaches a predetermined temperature, for example, set within the range of 150°C to 350°C, and reverses its curved shape again when it reaches another predetermined temperature, for example, set below -35°C.

[0003] Patent Document 2 describes a thermostat equipped with a bimetal and a movable plate. The movable plate is provided with a fulcrum forming portion that forms a fulcrum when the bimetal reverses.

[0004] Japanese Patent Application Laid-Open No. 2011-187228 Japanese Utility Model Publication No. 6-14383

[0005] Once a non-automatic reset type temperature switch has been activated, it should not reset unless the ambient temperature becomes extremely low. However, there is a possibility that it may reset due to an external force even if the ambient temperature has not dropped to an extremely low level.

[0006] In view of the above circumstances, the present invention aims to provide a non-automatic reset type temperature switch that, once activated, is less likely to be reset by an external force even when the ambient temperature has not yet dropped to an extremely low temperature.

[0007] A temperature switch according to one embodiment of the present invention comprises a fixed contact, a thermally responsive element having a curved shape that reverses its shape when a predetermined temperature is reached, and a movable plate made of metal and elastic, which has a movable contact in contact with the fixed contact and a locking portion with which the thermally responsive element is locked; when the shape of the thermally responsive element is reversed, the movable plate locked by the thermally responsive element warps in a predetermined direction, the movable contact separates from the fixed contact, and a tongue portion formed on the movable plate protrudes in the direction opposite to the predetermined direction.

[0008] According to the present invention, a non-automatic reset type temperature switch is provided which, after being activated once, is less likely to be reset by an external force even when the ambient temperature has not yet dropped to an extremely low temperature.

[0009] FIG. 1 is a perspective view of a temperature switch according to a first embodiment. FIG. 2 is a perspective view of a movable plate according to a first embodiment. FIG. 3 is a cross-sectional view of a temperature switch according to a first embodiment. FIG. 4 is a cross-sectional view of a temperature switch according to a first embodiment. FIG. 5 is a perspective view of a movable plate according to a second embodiment. FIG. 6 is a cross-sectional view of a temperature switch according to a second embodiment. FIG. 7 is a cross-sectional view of a temperature switch according to a second embodiment. FIG. 8 is a perspective view of a movable plate according to a third embodiment. FIG. 9 is a cross-sectional view of a temperature switch according to a third embodiment. FIG. 10 is a cross-sectional view of a temperature switch according to a third embodiment.

[0010] The present invention will be described below based on the illustrated embodiments, but the present invention is not limited to the embodiments described below.

[0011] A bimetal element, which is a thermo-responsive element, is made by bonding two metal plates with different thermal expansion coefficients together and has a curved shape. A thermo-responsive element such as a bimetal element has a first reversal temperature at which the curved shape reverses with an increase in temperature and a second reversal temperature at which the curved shape reverses again with a decrease in temperature after the reversal. The first reversal temperature is higher than the second reversal temperature.

[0012] In some cases, the difference between the first and second reversal temperatures of a thermally responsive element is large, with the second reversal temperature set to an extremely low temperature below the lowest temperature in a typical living environment. For example, the first reversal temperature is set between 150°C and 350°C, and the second reversal temperature is set to -35°C or below. Temperature switches equipped with such a thermally responsive element are called non-automatic reset types. Non-automatic reset type temperature switches are incorporated into electrical devices (e.g., hair dryers) that require the electrical circuit not to return to a conductive state under normal circumstances after the temperature switch has been activated (i.e., after the thermally responsive element has been reversed and the electrical circuit has been opened). If a temperature switch is activated in such an electrical device, the temperature switch must be replaced in order to use the electrical device again.

[0013] A non-automatic reset type temperature switch is a single operation device (SOD) that, once activated, will not reset unless the ambient temperature reaches a reset temperature that is set lower than room temperature.

[0014] A first reversal temperature and a second reversal temperature are set for the thermally responsive element alone. Furthermore, an operating temperature and a reset temperature are set for the temperature switch equipped with the thermally responsive element. Depending on the manner in which the thermally responsive element is mounted on the temperature switch, the first reversal temperature of the thermally responsive element and the operating temperature of the temperature switch are not strictly equal, but are generally equal. Similarly, the second reversal temperature of the thermally responsive element and the reset temperature of the temperature switch are not strictly equal, but are generally equal.

[0015] The reversal temperature of the thermally responsive element is set by its curvature processing, such that the thermally responsive element approaches a flat shape as the ambient temperature increases and approaches a first reversal temperature, and then changes to a curved shape in the opposite direction from the initial shape when the ambient temperature reaches the first reversal temperature.

[0016] In a non-automatic reset type temperature switch, the reversal of the thermally responsive element lifts the movable plate, opening the electrical circuit. At this time, a reaction force acts on the thermally responsive element from the movable plate. As mentioned above, a second reversal temperature is set for the thermally responsive element alone, and a reset temperature is set for the temperature switch, but due to the influence of the reaction force, the reset temperature is slightly higher than the second reversal temperature.

[0017] In electrical equipment incorporating a non-automatic reset type temperature switch, after the temperature switch has operated, an impact such as a drop can cause the thermally responsive element to buckle and revert, even if the temperature is higher than the reset temperature, causing the temperature switch to reset. This phenomenon depends on the elastic force of the movable plate lifted by the thermally responsive element, the magnitude of the spring load on the thermally responsive element, the size and spring load of the thermally responsive element itself, etc.

[0018] The embodiments described below relate to a non-automatic reset type temperature switch that is difficult to reset even if it receives a shock at room temperature after it senses an abnormal temperature and operates.

[0019] The movable plate is formed with a tongue portion. When the movable plate body is warped upward due to the inversion of the thermally responsive element, the tongue portion does not warp due to two state changes that occur in the movable plate, and protrudes from the movable plate body.

[0020] When the shape of the thermally responsive element is reversed and the movable plate is lifted, the thermally responsive element acts on three points: two claws formed on the movable plate that lock the thermally responsive element, and a protrusion that serves as a fulcrum when the thermally responsive element is reversed and is provided on the terminal to which the movable plate is connected so as to face the center of the thermally responsive element. As a result, the tip of the movable plate is lifted, and the movable contact provided on the tip of the movable plate separates from the fixed contact, opening the electric circuit.

[0021] The first state change is caused by the warping of the movable plate itself, and the tip where the tongue is attached protrudes downward relatively due to the warping that occurs in the movable plate body. While the movable plate body is significantly warped upward due to the shape reversal of the thermally responsive element, the tongue provided on the movable plate does not warp and protrudes downward relatively from the upward warped movable plate body.

[0022] The second state change occurs when the inverted thermally responsive element pushes against a rib-like protrusion provided on the upper surface of the tongue portion, pushing the tongue portion downward.

[0023] When the thermally responsive element is inverted, the movable plate body is bent upward, and the center of the thermally responsive element serves as a fulcrum, transitioning to an open temperature switch state. In this state, if the protrusion of the tongue portion of the movable plate is large, the tip of the tongue portion will be engaged with the insulating plate. In this state, the spring load of the movable plate on the thermally responsive element is reduced or released. As a result, even if an impact force is applied, the movable plate is less likely to be displaced, and since there is no large spring load acting on the thermally responsive element, the temperature switch is less likely to return to its original position due to the impact.

[0024] Even if the tip of the protruding tongue is not in contact with the insulating plate, the applied impact will cause the tip of the tongue to come into contact with the insulating plate, causing the spring load of the movable plate on the thermally responsive element to be suddenly released, making it less likely that the thermally responsive element will reverse again due to the impact.

[0025] In this way, whether the tongue portion is in contact with the insulating plate or not after the thermally responsive element is inverted, the thermally responsive element can maintain a stable shape at that temperature without buckling. As a result, as a temperature switch that acts as a protection device against overheating, recovery due to impact is suppressed, and the possibility of maintaining the open state of the electrical circuit is increased.

[0026] Furthermore, the contact pressure of the fixed contact and the movable contact can be ensured within a safe temperature range by pressing the thermally responsive element from above with the claws that lock the thermally responsive element to the movable plate. After the thermally responsive element flips over due to the detection of an abnormal temperature, the possibility of the thermally responsive element maintaining its flipped shape can be further increased by pressing the fulcrum in the center of the thermally responsive element from behind in the flipping direction.

[0027] 1, 2, and 3A show a non-automatic reset type temperature switch 100 that is a generally rectangular plate-like body. In these figures, the X-axis, Y-axis, and Z-axis represent the longitudinal, width, and height directions of the temperature switch 100, respectively. The positive X-axis direction is also referred to as the first longitudinal direction of the temperature switch 100, and the negative X-axis direction is also referred to as the second longitudinal direction of the temperature switch 100. The positive Y-axis direction (toward the left with respect to the first longitudinal direction) is also referred to as the first width direction of the temperature switch 100, and the negative Y-axis direction is also referred to as the second width direction of the temperature switch 100. The positive Z-axis direction (direction from the back surface to the front surface of the temperature switch 100) is also referred to as the first height direction of the temperature switch 100, and the negative Z-axis direction is also referred to as the second height direction of the temperature switch 100.

[0028] The temperature switch 100 includes an elongated insulating plate 105 extending along the longitudinal direction of the temperature switch, and a first terminal 110 and a second terminal 120 attached to an end portion of the insulating plate 105 on a second longitudinal side and an end portion of the insulating plate 105 on a first longitudinal side, respectively. The insulating plate 105 is formed from ceramic that can withstand high temperatures, or from a thermosetting resin that is highly hard and resistant to thermal deformation.

[0029] The first terminal 110 and the second terminal 120 are made by bending a metal plate. Both terminals are connected to an electrical circuit (a circuit external to the temperature switch 100) of an electrical device in which the temperature switch 100 is mounted. The first terminal 110 includes a main body 111 located on the second longitudinal side of the temperature switch and generally flush with the rear surface of the insulating plate 105, and an extension 112 located on the first longitudinal side of the temperature switch and in contact with the front surface of the insulating plate 105. Similarly, the second terminal 120 includes a main body 121 located on the first longitudinal side of the temperature switch and generally flush with the rear surface of the insulating plate 105, and an extension 122 located on the second longitudinal side of the temperature switch and in contact with the front surface of the insulating plate 105.

[0030] The end of the extension 112 of the first terminal 110 on the first longitudinal side of the temperature switch is bent to form a standing portion 112a that stands in the first height direction of the temperature switch. The standing portion 112a is approximately perpendicular to the insulating plate 105. The top of this standing portion 112a serves as a fulcrum when the thermally responsive element (described below) is turned over.

[0031] The temperature switch 100 further includes a movable plate 130. The movable plate 130 is generally rectangular and disposed generally horizontally with its longitudinal direction aligned with the longitudinal direction of the temperature switch 100, or more precisely, slightly inclined upward in the first longitudinal direction. The movable plate 130 is formed by processing an elastic metal plate. A generally U-shaped first notch N1 is formed in the movable plate 130 slightly closer to the first longitudinal direction than the center, thereby forming a first claw portion 131. The first claw portion 131 includes a base end portion that stands up from the movable plate main body in the first height direction and an extension portion that extends from the top of the base end portion in the second longitudinal direction.

[0032] The movable plate 130 further has a second notch N2 that is generally U-shaped and located slightly closer to the second longitudinal direction than the center, thereby forming a second claw portion 132. The second claw portion 132 has a base end that stands upright in the first height direction from the movable plate body, and an extension that extends in the first longitudinal direction from the top of the base end.

[0033] The dimension of the extension portion of the second claw portion 132 in the longitudinal direction of the temperature switch is greater than the dimension of the extension portion of the first claw portion 131 in the longitudinal direction of the temperature switch. The tip of the upright portion 112a is located slightly below the tip of the extension portion of the second claw portion 132. A portion of the movable plate 130 that is closer to the second direction in the longitudinal direction of the temperature switch than the base end of the second claw portion 132 is fixed to the extension portion 112 of the first terminal 110.

[0034] Two upright claw portions 133 standing in the first height direction are provided on both widthwise sides of the movable plate 130. The two upright claw portions 133 face each other in the width direction of the movable plate so as to sandwich the vicinity of the tip end of the extension portion of the second hook portion 132 therebetween.

[0035] A fixed contact 123 is provided on the surface of the extension 122 of the second terminal 120. A movable contact 134 that can be brought into contact with and separated from the fixed contact 123 is provided on the back surface of the tip end of the movable plate 130 (the end on the first longitudinal direction side of the temperature switch).

[0036] A substantially U-shaped third notch N3 is formed in the movable plate 130 between the first notch N1 and the second notch N2. The third notch N3 does not communicate with the first notch N1 but communicates with the second notch. This third notch N3 forms a tongue portion 135. The tongue portion 135 extends from its base in the second longitudinal direction of the temperature switch, with its tip portion 135a bent and extending downward. The tip portion 135a is substantially perpendicular to the insulating plate 105.

[0037] The temperature switch 100 further includes a thermally responsive element 140 mounted on the movable plate 130. The thermally responsive element 140 is a plate-like body, and is engaged with the movable plate 130 by a first claw portion 131, a second claw portion 132, and two standing claw portions 133. The tip of the second claw portion 132 is located above the center of the thermally responsive element 140, and the top of the standing portion 112a is located below the center of the thermally responsive element 140.

[0038] 3A, at room temperature, the thermally responsive element 140 is curved so as to be convex upward (in the first direction along the height of the thermal switch), and the movable contact 134 is in contact with the fixed contact 123. In other words, the thermal switch 100 is in an energized state. Because the center of the thermally responsive element 140 is pressed downward by the tip of the second claw portion 132, the main body of the movable plate 130 is pressed downward by the peripheral portion surrounding the center of the thermally responsive element 140. As a result, the movable contact 134 is pressed against the fixed contact 123, increasing the contact pressure between the contacts.

[0039] The tip portion 135 a is located slightly closer to the first direction in the longitudinal direction of the temperature switch than the upstanding portion 112 a , and is located between the center of the thermally responsive element 140 and the insulating plate 105 .

[0040] If the ambient temperature of the thermal switch 100 reaches its operating temperature for some reason, the thermally responsive element 140 will invert around the top of the upright portion 112a as a fulcrum and curve downward, as shown in FIG. 3B . Because the portion of the movable plate 130 that is closer to the second longitudinal direction of the thermal switch than the base end of the second claw portion 132 is fixed, the end of the thermally responsive element 140 that is engaged with the first claw portion 131 and that is closer to the first longitudinal direction of the thermal switch will spring up. This causes the tip of the movable plate 130 that is closer to the first longitudinal direction of the thermal switch to be lifted. The main body of the movable plate 130 will bend upward, and the movable contact 134 will move away from the fixed contact 123. This means that the electrical circuit in which the thermal switch is installed will be interrupted.

[0041] When the main body of the movable plate 130 is warped upward, the tongue portion 135 formed on the movable plate 130, particularly the tip portion 135a, protrudes downward.

[0042] The thermally responsive element 140 is formed by shallow drawing to have a curved shape. The non-automatic reset type temperature switch 100 has an operating temperature set higher than room temperature and a reset temperature set lower than room temperature (below freezing). Therefore, once the temperature switch 100 has operated, the contacts remain open at room temperature. Even if an impact is applied in this state, the downward-hanging tongue portion 135 and tip portion 135a come into contact with the insulating plate 105, suppressing vibration of the movable plate 130 and reversal of the thermally responsive element 140, thereby maintaining the temperature switch 100 in an open state.

[0043] If a large impact is applied to a temperature switch having a movable plate without a tongue portion 135, the movable plate will vibrate significantly, potentially causing the thermally responsive element to buckle and re-reverse even at room temperature. In a thermally responsive element, the region between the first reversal temperature and the second reversal temperature is the hysteresis region. In the hysteresis region, the metastable state is determined by which of the two reversal temperatures the ambient temperature of the temperature switch is closer to. When the room temperature region is close to the second reversal temperature, the shape after re-reversal is in the metastable region, so if buckling occurs, re-reversal will occur even if the ambient temperature is above the second reversal temperature.

[0044] On the other hand, in the temperature switch 100, a tongue portion 135 is provided on the movable plate 130, and after the temperature switch 100 is activated, the tongue portion 135 protrudes downward, i.e., toward the insulating plate 105. Therefore, even if an impact is applied to the temperature switch 100, the vibration of the movable plate 130 is suppressed by the tongue portion 135 in contact with the insulating plate 105, thereby reducing the possibility of resetting even at room temperature.

[0045] In this way, the non-automatic reset type temperature switch 100 reduces the possibility that, after it has been activated, it will be reset by an external force even though the ambient temperature has not yet dropped to an extremely low temperature.

[0046] The movable plate 130 is formed with a first claw portion 131, a second claw portion 132, and a tongue portion 135. A space is formed in the center of the movable plate 130 by the interconnected notches N2 and N3. Along its longitudinal direction, the movable plate 130 can be divided into a first region R1 extending from the tip of the movable plate to the base of the tongue portion 135, a third region R3 (a region fixed to the extension portion 112 of the first terminal 111) extending from the base of the second claw portion 132 to the base end of the movable plate, and a second region R2 between the first region R1 and the third region R3 (see FIG. 2). When the thermally actuated element is inverted, two regions, the first region and the second region, are displaced. The second region is particularly displaced, and the tongue portion 135, whose base is located in the first region where the deflection is less significant, is consequently displaced downward from the second region.

[0047] The thermally actuated element has a good balance of driving force and displacement when the movable plate is driven by the end portion, which displaces more than the center portion, using the center portion as a fulcrum. On the other hand, to prevent buckling of the thermally actuated element 140 due to impact, it is desirable to locate the point of application closer to the end portion of the thermally actuated element, which displaces more than the center portion during reversal. To prevent buckling due to impact, it is desirable for the point of application between the thermally actuated element and the tongue portion to be farther from the center of the thermally actuated element. For these reasons, it is preferable that the X-axis dimensions of the first region R1, second region R2, and third region R3 are approximately equal. Furthermore, when viewed from the width direction of the thermal switch 100 ( FIG. 3A ), the region of the thermally actuated element between the center of the thermally actuated element and a point spaced 1 / 3 of the longitudinal dimension of the thermally actuated element from the center of the thermally actuated element along the positive longitudinal direction of the thermally actuated element is indicated by the symbol RG. It is preferable that (1) the point at which the thermally responsive element drives the tongue portion, (2) the point at which the tongue portion contacts the insulating plate, and (3) the boundary between the movable plate and the tongue portion are located below region RG when viewed in the width direction of the temperature switch 100.

[0048] A first convex portion (rib) 136 extending in the longitudinal direction of the temperature switch may be formed on the surface of the tongue portion 135. Furthermore, a second convex portion (rib) 137 extending in the width direction of the temperature switch may be formed on the movable plate 130 between the convex portion 136 and the second notch N2. The center of the second convex portion 137 contacts the end of the first convex portion 136 on the first direction side in the longitudinal direction of the temperature switch. Both convex portions are convex on the front surface of the tongue portion 135 and concave on the back surface of the tongue portion 135, and are provided to support the inversion of the thermally actuated element 140. Furthermore, both convex portions also serve as reinforcement to increase the rigidity of the tongue portion 135. The inverted thermally actuated element 140 presses the convex portion 136, causing the tip of the tongue portion 135 to be displaced further downward.

[0049] The tip 135a of the tongue portion 135 is bent downward so as to easily contact or engage with the insulating plate 105 after the thermally responsive element 140 is turned over. When the movable plate 130 is lifted, the tip 135a is positioned approximately perpendicular to the insulating plate 105. The tip 135a does not need to be bent downward, and after the thermally responsive element 140 is turned over, the tip 135a may or may not contact the insulating plate 105. In any case, when vibration occurs in the movable plate 130 due to an impact or the like, it is sufficient that the tip 135a comes into contact with the insulating plate 105 and absorbs the impact.

[0050] If the tongue portion 135 comes into contact with the insulating plate 105 during the process of the shape of the thermally responsive element 140 changing toward reversal or at the moment of reversal, the temperature switch 100 may operate at a temperature different from the set operating temperature. Therefore, in order to prevent the tongue portion 135 from coming into contact with the insulating plate 105 during the process of the shape of the thermally responsive element 140 changing toward reversal or at the moment of reversal, a groove 105a can be formed in the insulating plate 105. After the thermally responsive element 140 is reversed, the tongue portion 135 may come into contact with a portion of the insulating plate 105 where the groove 105a is not formed.

[0051] The engagement of the tongue portion 135 with the insulating plate 105 continues unless the ambient temperature drops to the return temperature. Even if the return temperature is extremely low, if the switch returns to normal, the protrusion of the tongue portion is eliminated. The engagement continues until the contacts come into contact with each other (i.e., until the movable plate 130 returns to normal), and the switch can be maintained in an open state.

[0052] Second Embodiment Fig. 4 shows a movable plate 230 according to a second embodiment, and Fig. 5A (before inversion) and Fig. 5B (after inversion) show a temperature switch 200 including the movable plate 230. Elements similar to those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0053] The tongue portion 235 is formed by being cut down by an amount equivalent to the plate thickness so as not to interfere with both side portions of the third notch N3 in the movable plate 230. A cut-and-raised portion 236 is formed in the center of the tongue portion 235, with which the thermally responsive element 140 comes into contact. A tip portion 235a of the tongue portion 235 is bent downward, and the tip portion 235a may be approximately perpendicular to the insulating plate 105.

[0054] The movable plate 230 is manufactured through the following steps: a step of cutting out the tongue portion 235; a step of cutting the outer shape of the tongue portion 235; a step of forming the cut-and-raised portion 236; and a step of cutting down and bending the tongue portion 235.

[0055] In this embodiment, when the thermally responsive element 140 is reversed, the rear surface (the surface on the negative Z-axis direction side) of the thermally responsive element 140 warps and presses the cut-and-raised portion 236. At the same time, the thermally responsive element 140 contacts the first claw portion 131 and lifts the movable plate 230. After the thermally responsive element 140 is reversed, the cut-and-raised portion 236 is pressed, causing the tongue portion 235 to protrude significantly downward from the movable plate body, and the tip portion 236 contacts or engages with the insulating plate 105.

[0056] <Third embodiment> Fig. 6 shows a movable plate 330 according to a third embodiment, and Fig. 7A (before inversion) and Fig. 7B (after inversion) show a temperature switch 300 including the movable plate 330. Elements similar to those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

[0057] The tongue portion 335 is formed by being cut down by an amount equivalent to the plate thickness so as not to interfere with both side portions of the third notch N3 in the movable plate 330. A cut-and-raised portion 336 is formed in the center of the tongue portion 335, with which the thermally responsive element 140 comes into contact. Unlike the second embodiment, the tip portion 335a of the tongue portion 335 is not bent downward. In other words, the tongue portion 335 is easier to process than the tongue portions 135 and 235, which have bent tips.

[0058] As with the first embodiment, the temperature switch 200 of the second embodiment and the temperature switch 300 of the third embodiment also reduce the possibility that, after operating once, the switch will be reset by an external force even if the ambient temperature has not yet dropped to an extremely low temperature.

[0059] The following supplementary notes are disclosed regarding the embodiments described so far: [Supplementary Note 1] A non-automatic reset temperature switch comprising: a fixed contact, a thermally responsive element having a curved shape and reversing its shape at a predetermined temperature, and a movable plate made of metal and having elasticity, and provided with a movable contact in contact with the fixed contact and a locking portion with which the thermally responsive element is locked, wherein when the shape of the thermally responsive element is reversed, the movable plate with which the thermally responsive element is locked warps in a predetermined direction, the movable contact separates from the fixed contact, and a tongue portion formed on the movable plate protrudes in a direction opposite to the predetermined direction. [Supplementary Note 2] The temperature switch according to Supplementary Note 1, further comprising: a first terminal connected to the movable plate; a second terminal provided with the fixed contact; and an insulating plate to which the first terminal and the second terminal are attached, wherein the movable plate is substantially rectangular, a base end in the longitudinal direction of the movable plate is attached to the first terminal, the tongue portion protruding toward the base end in the longitudinal direction is formed in a central portion in the longitudinal direction of the movable plate, and the movable contact is provided at a tip end in the longitudinal direction of the movable plate, wherein a tip end of the tongue portion is not in contact with the insulating plate before the thermally responsive element is flipped, and a tip end of the tongue portion contacts the insulating plate after the thermally responsive element is flipped. [Supplementary Note 3] The temperature switch according to Supplementary Note 2, further comprising: a groove formed on the insulating plate, wherein the tongue portion does not interfere with the insulating plate before the thermally responsive element is flipped, and the tongue portion contacts a portion of the insulating plate where the groove is not formed after the thermally responsive element is flipped. [Supplementary Note 4] The temperature switch according to Supplementary Note 2 or 3, wherein a tip of the tongue portion is bent so as to be approximately perpendicular to the insulating plate. [Supplementary Note 5] The temperature switch according to any one of Supplementary Notes 1 to 3, wherein a standing portion approximately perpendicular to the thermally responsive element is formed on the first terminal, and the standing portion serves as a fulcrum when the thermally responsive element is reversed.

[0060] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made based on the technical concept of the present invention.

[0061] REFERENCE SIGNS LIST 100 Temperature switch 105 Insulating plate 110 First terminal 120 Second terminal 123 Fixed contact 130 Movable plate 131, 132 Claw portion 133 Standing claw portion 134 Movable contact 135 Tongue portion 135a Tip portion 140 Thermally responsive element

Claims

1. A non-automatic reset type temperature switch comprising: a fixed contact; a thermoresponsive element having a curved shape which reverses its shape at a predetermined temperature; and a movable plate made of metal and having elasticity, a movable contact in contact with the fixed contact and a locking portion with which the thermoresponsive element is locked; when the shape of the thermoresponsive element is reversed, the movable plate with which the thermoresponsive element is locked warps in a predetermined direction, the movable contact separates from the fixed contact, and a tongue portion formed on the movable plate protrudes in the direction opposite to the predetermined direction.

2. A temperature switch as claimed in claim 1, further comprising: a first terminal connected to said movable plate; a second terminal provided with said fixed contact; and an insulating plate to which said first terminal and said second terminal are attached, said movable plate being substantially rectangular, a base end in the longitudinal direction of said movable plate being attached to said first terminal, said tongue portion being formed in a longitudinal central portion of said movable plate protruding towards said base end in the longitudinal direction, said movable contact being provided at a tip end in the longitudinal direction of said movable plate, and before said thermally responsive element is reversed, a tip end of said tongue portion is not in contact with said insulating plate, and after said thermally responsive element is reversed, a tip end of said tongue portion comes into contact with said insulating plate.

3. A temperature switch as described in claim 2, wherein a groove is formed on the insulating plate, the tongue portion does not interfere with the insulating plate before the thermally responsive element is flipped over, and the tongue portion comes into contact with a portion of the insulating plate where the groove is not formed after the thermally responsive element is flipped over.

4. A temperature switch as claimed in claim 2 or 3, wherein the tip of said tongue portion is bent so as to be approximately perpendicular to said insulating plate.

5. A temperature switch as claimed in any one of claims 1 to 3, wherein a standing portion is formed on the first terminal which is approximately perpendicular to the thermally responsive element, and the standing portion serves as a fulcrum when the thermally responsive element is inverted.

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