WO2020095694A1 - Thermally-actuated element, breaker, safety circuit, and secondary battery pack - Google Patents

Thermally-actuated element, breaker, safety circuit, and secondary battery pack Download PDF

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Publication number
WO2020095694A1
WO2020095694A1 PCT/JP2019/041654 JP2019041654W WO2020095694A1 WO 2020095694 A1 WO2020095694 A1 WO 2020095694A1 JP 2019041654 W JP2019041654 W JP 2019041654W WO 2020095694 A1 WO2020095694 A1 WO 2020095694A1
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WO
WIPO (PCT)
Prior art keywords
breaker
responsive element
side wall
movable piece
contact
Prior art date
Application number
PCT/JP2019/041654
Other languages
French (fr)
Japanese (ja)
Inventor
恒平 山本
Original Assignee
ボーンズ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ボーンズ株式会社 filed Critical ボーンズ株式会社
Publication of WO2020095694A1 publication Critical patent/WO2020095694A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H37/00—Thermally-actuated switches
    • H01H37/02—Details
    • H01H37/32—Thermally-sensitive members
    • H01H37/52—Thermally-sensitive members actuated due to deflection of bimetallic element
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H37/00—Thermally-actuated switches
    • H01H37/02—Details
    • H01H37/32—Thermally-sensitive members
    • H01H37/52—Thermally-sensitive members actuated due to deflection of bimetallic element
    • H01H37/54—Thermally-sensitive members actuated due to deflection of bimetallic element wherein the bimetallic element is inherently snap acting

Definitions

  • the present invention relates to a heat responsive element or the like formed in a plate shape suitable for use in a small breaker.
  • breakers have been used as protective devices (safety circuits) for secondary batteries and motors of various electric devices.
  • Patent Document 1 discloses a breaker to which a bimetal is applied as a heat responsive element.
  • the bimetal is an element that is formed by laminating two kinds of plate-shaped metal materials having different thermal expansion coefficients, and changes the shape according to the temperature change (thermal deformation) to control the conduction state of the contacts.
  • parts such as a fixed piece, a movable piece, a thermo-responsive element, and a PTC thermistor are housed in a case, and terminals of the fixed piece and the movable piece protrude from the case, so that electric equipment Used by being connected to a circuit.
  • the breaker operates when the temperature of the rechargeable battery during charging / discharging rises excessively, or when an abnormal condition occurs, such as when an overcurrent flows through a motor or the like installed in equipment such as automobiles and home appliances. Shut off the current to protect the secondary battery and motor.
  • the breaker used as such a protection device operates accurately following a temperature change (has good temperature characteristics) and has a stable resistance value when energized in order to ensure the safety of the device. Required to be present.
  • the breaker when used as a protection device for a secondary battery or the like equipped in an electric device such as a notebook personal computer, a tablet type personal digital assistant, or a thin multifunctional mobile phone called a smartphone, the above-mentioned breaker is used.
  • miniaturization is required.
  • mobile information terminal devices in recent years, there is a strong tendency for users to miniaturize, and devices newly released by each company tend to be designed small in order to secure superiority in design. It is remarkable.
  • the movable piece is composed of the above bimetal
  • the elastic force of the movable piece is increased, the force generated during thermal deformation is also increased at the same time, so the above problems do not occur easily. Therefore, the above-mentioned problem is peculiar to the form in which the movable piece and the thermoresponsive element are composed of separate parts.
  • the present invention has been made to solve the above problems, and a main object of the present invention is to provide a thermal responsive element, a breaker, and the like that can easily realize miniaturization while maintaining electrical resistance when conducting.
  • thermoresponsive element of the present invention is a plate-shaped thermoresponsive element, and has a long side extending in the length direction in a plan view viewed from the thickness direction, and the length. It is formed in a rectangular shape having a short side extending in the width direction perpendicular to the vertical direction, and a widening portion for expanding the width dimension is provided in the central portion in the length direction, and the width toward the central portion. It is characterized in that the dimensions are gradually increasing.
  • thermoresponsive element it is preferable that the long side is enlarged in a barrel shape.
  • thermoresponsive element it is preferable that the corners where the long sides and the short sides intersect are rounded.
  • the breaker of the present invention has the thermal responsive element, a fixed contact, an elastic portion that elastically deforms, and a movable contact at the tip of the elastic portion, and presses the movable contact against the fixed contact.
  • a breaker comprising a movable piece and a first case having a recess for accommodating the movable piece and the heat responsive element, wherein the heat responsive element is deformed in accordance with a change in temperature to move the movable piece. It is possible to shift the state of the piece from a conductive state in which the movable contact contacts the fixed contact to a shut-off state in which the movable contact is separated from the fixed contact, and the first case is located outside the recess in the width direction. It has a side wall, and the thickness of the side wall is gradually reduced toward the central portion of the side wall in the longitudinal direction.
  • a second case that covers at least a part of the recess is further provided, the second case has a fixing surface that is fixed to an end surface of the side wall, and the fixing surface has the It is preferable that a projecting portion that projects toward the end surface and that is continuous along the length direction is provided, and that the projecting portion is formed outward of the inner side surface of the side wall in the width direction.
  • a cross-sectional area of the protrusion that is perpendicular to the length direction decreases toward the central portion of the side wall in the length direction.
  • the safety circuit for electric equipment of the present invention is characterized by including the breaker.
  • a secondary battery pack for electric equipment of the present invention is characterized by including the breaker.
  • the force generated by the thermoresponsive element during the thermal deformation depends on the thickness of the thermoresponsive element.
  • the inventor of the present application has noticed that it is difficult to obtain stable temperature characteristics in the thermal responsive element in which only the thickness dimension is increased.
  • the width dimension of the central portion in the length direction effectively acts to stabilize the temperature characteristics.
  • the widened portion for expanding the width dimension is provided in the central portion in the length direction, and the width dimension is gradually increased toward the central portion.
  • the width dimension of the thermoresponsive element is suppressed from the central portion toward the short side, the occupied area of the thermoresponsive element in a plan view is suppressed, and the miniaturization of the thermoresponsive element is easily realized.
  • the thermal responsive element since the thermal responsive element is provided, it is possible to easily reduce the electric resistance during conduction by adopting the movable piece that generates a large elastic force. Moreover, since the thickness of the side wall of the first case is gradually reduced toward the central portion in the length direction of the side wall, the breaker can be easily miniaturized together with the heat responsive element.
  • the perspective view before an assembly showing the schematic structure of the breaker by one embodiment of the present invention Sectional drawing which shows the said breaker in a normal charge or discharge state. Sectional drawing which shows the said breaker at the time of an overcharge state or an abnormality.
  • the top view which shows another modification of the said thermoresponsive element The perspective view which shows another modification of the said thermoresponsive element.
  • a breaker according to an embodiment of the present invention will be described with reference to the drawings.
  • 1 to 3 show the configuration of the breaker 1.
  • the breaker 1 is mounted on an electric device or the like and protects the electric device from an excessive temperature rise or an overcurrent.
  • the breaker 1 includes a fixed piece 2 having a fixed contact 21, a movable piece 4 having a movable contact 41 at a tip thereof, a thermal responsive element 5 that deforms with a temperature change, and a PTC (Positive Temperature Coefficient) thermistor 6.
  • the case 10 includes a case body (first case) 7, a lid member (second case) 8 mounted on the upper surface of the case body 7, and the like.
  • the fixing piece 2 is formed, for example, by pressing a metal plate containing copper as a main component (other than this, a metal plate of copper-titanium alloy, nickel silver, brass, etc.), and is insert-molded into the case body 7. It is embedded.
  • a terminal 22 that is electrically connected to an external circuit is formed at one end of the fixed piece 2, and a support portion 23 that supports the PTC thermistor 6 is formed at the other end side.
  • the PTC thermistor 6 is mounted on convex protrusions (doughs) 24 formed at three locations on the support portion 23 of the fixed piece 2 and supported by the protrusions 24.
  • the fixed contact 21 is formed at a position facing the movable contact 41 by clad, plating or coating of a material having good conductivity such as silver, nickel, nickel-silver alloy, copper-silver alloy, gold-silver alloy. It is exposed from a part of the opening 73a formed inside the case body 7.
  • the terminal 22 is projected outward from the edge of the case body 7.
  • the support portion 23 is exposed from an opening 73d formed inside the case body 7.
  • the surface on the side where the fixed contact 21 is formed (that is, the upper surface in FIG. 1) is the A surface, and the opposite surface is the B surface. is doing.
  • the direction from the fixed contact 21 to the movable contact 41 is defined as the first direction and the direction opposite to the first direction is defined as the second direction
  • the A surface faces the first direction
  • the B surface faces the second direction.
  • the movable piece 4 is formed into an arm shape symmetrical with respect to the center line in the longitudinal direction by pressing a plate-shaped metal material containing copper or the like as a main component.
  • a movable contact 41 is formed at the tip of the movable piece 4 in the longitudinal direction.
  • the movable contact 41 is formed of, for example, a material similar to that of the fixed contact 21, and is joined to the tip end of the movable piece 4 by a method such as welding, clad, crimping, or the like.
  • a terminal 42 electrically connected to an external circuit is formed at the other end of the movable piece 4 in the longitudinal direction.
  • the movable piece 4 has a contact portion 43 and an elastic portion 44 between the movable contact 41 and the terminal 42.
  • the contact portion 43 contacts the case body 7 and the lid member 8 between the terminal 42 and the elastic portion 44.
  • the contact portion 43 has a protruding portion 43a that protrudes like a wing in the lateral direction of the movable piece 4. Since the protrusion 43a is provided, the contact portion 43 is sandwiched between the case body 7 and the lid member 8 in a wide and large area, and the movable piece 4 is firmly fixed to the case 10.
  • the elastic portion 44 extends from the contact portion 43 to the movable contact 41 side.
  • the movable piece 4 is cantilevered by the case 10 at the abutment portion 43 on the proximal end side of the elastic portion 44, and is elastically deformed in this state to be formed at the tip portion of the elastic portion 44.
  • the movable contact 41 that is present is pressed against the side of the fixed contact 21 and comes into contact with it, and the fixed piece 2 and the movable piece 4 can be energized.
  • the movable piece 4 is curved or bent in the elastic portion 44 by press working.
  • the degree of bending or bending is not particularly limited as long as the thermoresponsive element 5 can be housed therein, and may be appropriately set in consideration of the elastic force at the reversing operation temperature and the normal return temperature, the pressing force of the contacts, and the like.
  • a pair of protrusions 44 a and 44 b is formed on the surface B of the elastic portion 44 so as to face the thermoresponsive element 5.
  • the protrusion 44a protrudes toward the heat responsive element 5 at the base end side and contacts the heat responsive element 5 in a blocked state.
  • the protrusion 44b protrudes toward the heat responsive element 5 on the tip side (that is, the movable contact 41 side) of the protrusion 44a, and contacts the heat responsive element 5 in a blocked state.
  • the thermal responsive element 5 is deformed by overheating, the thermal responsive element 5 contacts the protrusions 44a and 44b, the deformation of the thermal responsive element 5 is transmitted to the elastic portion 44 via the protrusions 44a and 44b, and the movable piece 4 moves.
  • the tip is pushed up (see Fig. 3).
  • the heat responsive element 5 shifts the state of the movable piece 4 from a conductive state in which the movable contact 41 contacts the fixed contact 21 to a cutoff state in which the movable contact 41 is separated from the fixed contact 21.
  • the heat responsive element 5 is formed in a plate shape by laminating thin plate materials having different thermal expansion coefficients, and has an initial shape in which a cross section is curved in an arc shape. When the operating temperature is reached due to overheating, the curved shape of the thermal responsive element 5 reversely warps with snap motion, and is restored when the temperature falls below the return temperature due to cooling.
  • the initial shape of the thermoresponsive element 5 can be formed by press working.
  • thermoresponsive element 5 are not particularly limited as long as the elastic portion 44 of the movable piece 4 is pushed up by the backward warping operation of the thermoresponsive element 5 at the desired temperature and returned to its original state by the elastic force of the elastic portion 44.
  • a rectangular shape is desirable from the viewpoint of productivity and efficiency of reverse warping operation.
  • thermoresponsive element 5 As the material of the heat-responsive element 5, two kinds of materials having different coefficients of thermal expansion, which are made of various alloys such as nickel silver, brass and stainless steel, are laminated and used in combination according to the required conditions.
  • a material of the thermoresponsive element 5 that can obtain a stable operation temperature and a stable return temperature it is desirable to combine a copper-nickel-manganese alloy on the high expansion side and an iron-nickel alloy on the low expansion side.
  • a material in which an iron-nickel-chromium alloy is combined on the high expansion side and an iron-nickel alloy is combined on the low expansion side can be mentioned.
  • there is a combination of an iron-nickel-chromium alloy on the high expansion side and an iron-nickel-cobalt alloy on the low expansion side there is a combination of an iron-nickel-chromium alloy on the high expansion side and an iron-nickel-cobalt alloy on the low expansion side.
  • the PTC thermistor 6 makes the fixed piece 2 and the movable piece 4 electrically conductive when the movable piece 4 is in the cutoff state.
  • the PTC thermistor 6 is arranged between the fixed piece 2 and the thermoresponsive element 5. That is, the support portion 23 of the fixed piece 2 is located immediately below the thermoresponsive element 5 with the PTC thermistor 6 interposed therebetween.
  • the type can be selected according to the needs of the operating current, the operating voltage, the operating temperature, the return temperature, etc.
  • the material and shape are not particularly limited as long as these characteristics are not impaired.
  • a ceramic sintered body containing barium titanate, strontium titanate or calcium titanate is used.
  • so-called polymer PTC in which conductive particles such as carbon are contained in polymer may be used.
  • the case body 7 and the lid member 8 constituting the case 10 are made of a thermoplastic resin such as flame-retardant polyamide, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polybutylene terephthalate (PBT) having excellent heat resistance. Has been done. A material other than the resin may be applied as long as the characteristics equal to or higher than those of the resin described above can be obtained.
  • a thermoplastic resin such as flame-retardant polyamide, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polybutylene terephthalate (PBT) having excellent heat resistance. Has been done.
  • a material other than the resin may be applied as long as the characteristics equal to or higher than those of the resin described above can be obtained.
  • the case main body 7 is formed with a recess 73 which is an internal space for housing the movable piece 4, the thermoresponsive element 5, the PTC thermistor 6, and the like.
  • the recess 73 has openings 73a and 73b for accommodating the movable piece 4, an opening 73c for accommodating the movable piece 4 and the thermoresponsive element 5, an opening 73d for accommodating the PTC thermistor 6, and the like. ing.
  • the edges of the movable piece 4 and the heat responsive element 5 incorporated in the case body 7 are respectively brought into contact with each other by the frame forming the recess 73 and guided when the heat responsive element 5 warps backward.
  • the lid member 8 is configured to cover the recess 73.
  • the lid member 8 may be configured to cover at least a part of the recess 73.
  • a metal plate containing copper or the like as a main component or a metal plate such as stainless steel may be embedded in the lid member 8 by insert molding. The metal plate appropriately contacts the surface A of the movable piece 4 to restrict the movement of the movable piece 4, and contributes to the downsizing of the breaker 1 while enhancing the rigidity and strength of the lid member 8 and thus the case 10 as a housing. To do.
  • the lid member 8 covers the case 73 so as to close the openings 73a, 73b, 73c and the like of the case body 7 that houses the fixed piece 2, the movable piece 4, the thermoresponsive element 5, the PTC thermistor 6 and the like. It is attached to the main body 7.
  • the case body 7 and the lid member 8 are joined by ultrasonic welding, for example.
  • FIG. 2 shows the operation of the breaker 1 in a normal charging or discharging state.
  • the thermoresponsive element 5 maintains the initial shape before reverse warpage.
  • the thermal responsive element 5 may be separated from the protrusions 44a and 44b of the movable piece 4 in the conductive state. As a result, the contact pressure between the movable contact 41 and the fixed contact 21 is increased, and the contact resistance between them is reduced.
  • FIG. 3 shows the operation of the breaker 1 in the overcharged state or the abnormal state.
  • the thermal responsive element 5 that has reached the operating temperature warps backward and contacts the elastic portion 44 of the movable piece 4, and the elastic portion 44 is pushed up to cause the fixed contact 21 and the movable contact 41 to contact each other. Are separated. At this time, the current flowing between the fixed contact 21 and the movable contact 41 is cut off.
  • the thermoresponsive element 5 comes into contact with the movable piece 4, and a slight leakage current flows through the thermoresponsive element 5 and the PTC thermistor 6.
  • the PTC thermistor 6 brings the fixed piece 2 and the movable piece 4 into conduction with each other via the thermal responsive element 5 that moves the movable piece 4 to the cutoff state.
  • the PTC thermistor 6 continues to generate heat as long as such a leakage current flows, and dramatically increases the resistance value while maintaining the thermoresponsive element 5 in the reverse warped state, so that the current passes through the path between the fixed contact 21 and the movable contact 41. Does not flow through and there is only the above-mentioned slight leakage current (constituting a self-holding circuit). This leakage current can be used for other functions of the safety device.
  • FIG. 4 is a plan view of the thermoresponsive element 5 viewed from its thickness direction.
  • the thermoresponsive element 5 is formed in a rectangular shape having a long side 51 extending in the length direction (longitudinal direction) D1 and a short side 52 extending in the width direction (shorter direction) D2 perpendicular to the length direction. ..
  • the elastic portion 44 of the movable piece 4 extends in the length direction D1 of the thermoresponsive element 5.
  • a widened portion 54 for widening the width dimension is provided in the central portion 53 of the heat responsive element 5 in the length direction D1.
  • the widened portion 54 is represented by a hatched region (hereinafter, the same applies to FIG. 5 and the like).
  • the force generated by the thermal response element 5 during thermal deformation depends on the thickness dimension of the thermal response element 5.
  • the thermal response element in which only the thickness dimension is increased it is stable. It may be difficult to obtain the desired temperature characteristics.
  • the inventors of the present application have found that the width dimension W1 of the central portion 53 effectively acts to stabilize the temperature characteristics particularly in the rectangular thermoresponsive element 5.
  • the width dimension W1 of the central portion 53 is the width dimension of the end edge portion in the length direction D1 (the length of the short side 52). It's bigger than W2. As a result, it is possible to increase the thickness dimension of the thermal responsive element 5 while stably securing excellent temperature characteristics, and it is possible to easily increase the force generated by the thermal responsive element 5 during the thermal deformation. Becomes
  • thermoresponsive element 5 of the present invention the width dimension gradually increases from the short side 52 toward the central portion 53, so that the stress distribution in the longitudinal direction D1 of the thermoresponsive element 5 is smoothed, and The temperature characteristic in the depth direction D1 is further stabilized.
  • the width dimension of the thermal response element 5 is suppressed from the central portion 53 of the thermal response element 5 toward the short side 52, the area occupied by the thermal response element 5 in a plan view is suppressed, and the thermal response element 5 is suppressed. Can be easily realized.
  • the central portion 53 of the thermal responsive element 5 is a region in which a large stress is generated when the thermal responsive element 5 is thermally deformed, and is, for example, W2 / 4 from the center of the thermal responsive element 5 in the length direction D1.
  • the areas are as follows:
  • the long side 51 of the thermoresponsive element 5 is enlarged and formed in a barrel shape.
  • the thermoresponsive element 5 has an arc-shaped contour 56 in which the central portion 53 is enlarged at the end edge in the width direction D2.
  • the “arc” is a concept including not only a part of the circumference of a perfect circle but also a part of the circumference of an ellipse.
  • FIG. 5 shows a thermoresponsive element 5A which is a modified example of the thermoresponsive element 5.
  • the thermal responsive element 5A differs from the thermal responsive element 5 in that the long side 51 is formed by a straight line, and the long side 51 is formed in a curved shape that is convex outward in the width direction D2.
  • the long side 51 is composed of a pair of straight lines inclined with respect to the length direction D1 and a straight line parallel to the length direction D1. A straight line parallel to the direction D1 may be omitted.
  • the heat responsive element 5A by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the heat responsive element 5A while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
  • FIG. 6 shows a thermoresponsive element 5B which is another modification of the thermoresponsive element 5.
  • the thermal responsive element 5B differs from the thermal responsive element 5 in that the long side 51 is formed in a curved shape that is convex inward in the width direction D2. Also in the thermal responsive element 5B, by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the thermal responsive element 5B while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
  • FIG. 7 shows a heat responsive element 5C which is another modification of the heat responsive element 5.
  • the thermal response element 5C is different from the thermal response element 5 in which the widened portion 54 is formed from the central portion 53 to the short side 52 in that the widened portion 54 is formed only in the central portion 53. Also in the heat responsive element 5C, by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the heat responsive element 5C while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
  • FIG. 8 shows a heat responsive element 5D which is another modification of the heat responsive element 5.
  • the heat responsive element 5D is different from the heat responsive element 5 in that the corner 55 where the long side 51 and the short side 52 intersect is rounded.
  • the corner 55 may be rounded.
  • the corner portion 55 may be chamfered linearly.
  • any one of the heat responsive elements 5 to 5D is provided, by adopting the movable piece 4 that generates a large elastic force, the electrical resistance at the time of conduction is increased. Can be easily reduced.
  • FIG. 9 shows the case body 7 in which the fixing piece 2 is insert-molded.
  • the case body 7 has a side wall 76 outside the recess 73 in the width direction D2.
  • the side wall 76 extends along the length direction D1 of the thermoresponsive element 5.
  • the thickness T of the side wall 76 gradually decreases toward the central portion 77 of the side wall 76 in the length direction D1. As a result, it is possible to prevent the central portion 77 of the side wall 76 from being enlarged in the width direction D2 when the thermal actuator 5 is applied to the breaker 1, and the breaker 1 can be easily miniaturized.
  • the case body 71 has a fixing surface 75 that is fixed to the lid member 8.
  • the fixing surface 75 is formed so as to surround the periphery of the recess 73.
  • the end surface 78 of the side wall 76 is fixed to the lid member 8 and constitutes a part of the fixed surface 75.
  • FIG. 10 shows the B side of the lid member 8.
  • the lid member 8 has a fixing surface 81 that is fixed to the fixing surface 75 of the case body 7.
  • the fixing surface 81 is formed at least in a region facing the fixing surface 75.
  • the fixing surface 81 is fixed to the end surface 78 in the region 82 that faces the end surface 78 of the side wall 76.
  • the area 82 of the fixing surface 81 is provided with a protruding portion 83 that protrudes toward the end surface 78. In FIG. 10, a part of the protruding portion 83 is broken.
  • the top of the protruding portion 83 first comes into contact with the fixing surface 75 when the lid member 8 is attached to the case body 7.
  • the pressure acting on the top of the protrusion 83 during ultrasonic welding increases, and the frictional heat generated between the top of the protrusion 83 and the fixing surface 75 increases.
  • the resin of the protruding portion 83 is easily melted, and the fixing between the fixing surface 75 and the fixing surface 81 becomes good.
  • the protrusion 83 extends continuously along the side wall 76 in the length direction D1. As a result, the adhesion between the end surface 78 of the side wall 76 and the fixing surface 81 becomes good. Further, the protruding portion 83 is formed outward of the inner side surface 79 (see FIG. 9) of the side wall 76 in the width direction D2. As a result, the melted resin of the protruding portion 83 is prevented from entering the concave portion 73 and interfering with the thermoresponsive element 5.
  • the cross-sectional area S of the protrusion 83 perpendicular to the length direction D1 is preferably reduced toward the central portion 77 of the side wall 76 in the length direction D1.
  • the molten resin of the protruding portion 83 is further suppressed from entering the concave portion 73 as a flash and interfering with the thermoresponsive element 5. Further, the melted resin of the protruding portion 83 is suppressed from becoming a flash and protruding from the outer side surface of the case 10.
  • the inner edge of the protruding portion 83 is formed along the inner side surface 79 of the side wall 76, and the outer edge of the protruding portion 83 is formed parallel to the outer edge of the lid member 8.
  • the width dimension W3 of the protruding portion 83 decreases toward the central portion 77, and the above-described distribution of the cross-sectional area S is easily realized.
  • the breaker 1 of the present invention is not limited to the configuration of the above embodiment, and may be implemented in various modes. That is, the heat responsive element 5 and the like are formed at least in a plate shape and extend in the plan view viewed from the thickness direction in the long side 51 extending in the length direction D1 and in the width direction D2 perpendicular to the length direction D1.
  • the width dimension is gradually increased toward the central portion 53 by forming the rectangular portion having the short side 52 and the widening portion 54 for enlarging the width dimension in the central portion 53 in the length direction D1. Just do it.
  • the method of joining the case body 7 and the lid member 8 is not limited to ultrasonic welding, and any method can be appropriately applied as long as the method can firmly join the two.
  • a liquid or gel adhesive may be applied / filled and cured to bond the two.
  • the case 10 is not limited to the form formed by the case body 7, the lid member 8 and the like, and may be formed by two or more parts.
  • the present invention can also be applied to a mode in which a movable piece and a terminal piece are separately molded and electrically connected by welding or the like, for example, as disclosed in JP-A-2016-35822. ..
  • the present invention can also be applied to a form in which the terminals 22 and 42 are exposed from the B surface of the case body 7.
  • the lid member 8 may be provided with an opening.
  • the opening penetrates the lid member 8 in the thickness direction.
  • the present invention can be applied to a form in which the lid member 8 is omitted from the case 10, that is, a form in which the recess 73 of the case body 7 is opened and the movable piece 4 and the like are exposed.
  • the distance between the fixed contact 21 and the movable contact 41 when the movable piece 4 is in the cutoff state can be increased more easily.
  • the terminal piece is insert-molded in the case body 7, and the movable piece 4 is welded to the terminal piece at the base end side thereof, as disclosed in JP-A-2016-35822. May be fixed by.
  • the PTC thermistor 6 has a self-holding circuit, but it is also applicable to a form in which such a configuration is omitted.
  • FIG. 11 shows a secondary battery pack 500.
  • the secondary battery pack 500 includes a secondary battery 501 and a breaker 1 provided in the output circuit of the secondary battery 501.
  • FIG. 12 shows a safety circuit 502 for electrical equipment.
  • the safety circuit 502 includes the breaker 1 in series in the output circuit of the secondary battery 501. According to the secondary battery pack 500 or the safety circuit 502 provided with the breaker 1, it is possible to manufacture the secondary battery pack 500 or the safety circuit 502 that can easily realize downsizing while maintaining the electrical resistance when conducting.

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  • Thermal Sciences (AREA)
  • Thermally Actuated Switches (AREA)

Abstract

A plate-like thermally-actuated element 5 is formed in a shape of a rectangle, in a plan view seen from the thickness direction, having long sides 51 extending in a lengthwise direction D1 and having short sides 52 extending in a width direction D2 perpendicular to the lengthwise direction D1. A wide section 54 at which the width dimension is widened is provided at the central portion 53 in the lengthwise direction D1, and thus the width dimension increases gradually toward the central portion 53.

Description

熱応動素子、ブレーカー、安全回路及び２次電池パックThermal actuator, breaker, safety circuit and secondary battery pack
　本発明は、小型のブレーカーに用いて好適な板状に形成された熱応動素子等に関するものである。 The present invention relates to a heat responsive element or the like formed in a plate shape suitable for use in a small breaker.
　従来、各種電気機器の２次電池やモーター等の保護装置（安全回路）としてブレーカーが使用されている。 Conventionally, breakers have been used as protective devices (safety circuits) for secondary batteries and motors of various electric devices.
　ブレーカーには、温度変化に応じて作動し、電流を導通又は遮断する熱応動素子が備えられている。特許文献１には、熱応動素子としてバイメタルを適用したブレーカーが示されている。バイメタルとは、熱膨張率の異なる２種類の板状の金属材料が積層されてなり、温度変化に応じて形状を変えること（熱変形）により、接点の導通状態を制御する素子である。同文献に示されたブレーカーは、固定片、可動片、熱応動素子、ＰＴＣサーミスター等の部品が、ケースに収納されてなり、固定片及び可動片の端子がケースから突出し、電気機器の電気回路に接続されて使用される。 The breaker is equipped with a thermo-responsive element that operates according to temperature changes and conducts or blocks current. Patent Document 1 discloses a breaker to which a bimetal is applied as a heat responsive element. The bimetal is an element that is formed by laminating two kinds of plate-shaped metal materials having different thermal expansion coefficients, and changes the shape according to the temperature change (thermal deformation) to control the conduction state of the contacts. In the breaker shown in the same document, parts such as a fixed piece, a movable piece, a thermo-responsive element, and a PTC thermistor are housed in a case, and terminals of the fixed piece and the movable piece protrude from the case, so that electric equipment Used by being connected to a circuit.
ＷＯ２０１１／１０５１７５号公報WO2011 / 105175
　ブレーカーは、充放電中の２次電池の温度が過度に上昇した場合、又は自動車、家電製品等の機器に装備されるモーター等に過電流が流れた場合等の異常が生じた際に、２次電池やモーター等を保護するために電流を遮断する。このような保護装置として用いられるブレーカーは、機器の安全を確保するために、温度変化に追従して正確に動作する（良好な温度特性を有する）ことと、通電時の抵抗値が安定していることが求められる。 The breaker operates when the temperature of the rechargeable battery during charging / discharging rises excessively, or when an abnormal condition occurs, such as when an overcurrent flows through a motor or the like installed in equipment such as automobiles and home appliances. Shut off the current to protect the secondary battery and motor. The breaker used as such a protection device operates accurately following a temperature change (has good temperature characteristics) and has a stable resistance value when energized in order to ensure the safety of the device. Required to be present.
  また、ブレーカーが、ノート型パーソナルコンピュータ、タブレット型携帯情報端末機器又はスマートフォンと称される薄型の多機能携帯電話機等の電気機器に装備される２次電池等の保護装置として用いられる場合、上述した安全性の確保に加えて、小型化が要求される。特に、近年の携帯情報端末機器にあっては、ユーザーの小型化の志向が強く、各社から新規に発売される機器は、デザイン上の優位性を確保するために、小型に設計される傾向が顕著である。こうした背景の下、携帯情報端末機器を構成する一部品として、２次電池と共に実装されるブレーカーもまた、さらなる小型化が強く要求されている。例えば、ケースの幅寸法（可動片の長手方向に垂直な短手方向の長さ）の小さいブレーカーが要望されている。 In addition, when the breaker is used as a protection device for a secondary battery or the like equipped in an electric device such as a notebook personal computer, a tablet type personal digital assistant, or a thin multifunctional mobile phone called a smartphone, the above-mentioned breaker is used. In addition to ensuring safety, miniaturization is required. In particular, with regard to mobile information terminal devices in recent years, there is a strong tendency for users to miniaturize, and devices newly released by each company tend to be designed small in order to secure superiority in design. It is remarkable. Against this background, there is also a strong demand for further miniaturization of the breaker mounted together with the secondary battery as one component constituting the portable information terminal device. For example, there is a demand for a breaker having a small width dimension of the case (length in the lateral direction perpendicular to the longitudinal direction of the movable piece).
　しかしながら、上記特許文献１に記載されているブレーカーにおいて、ケースの幅寸法が小さく設定された場合、熱応動素子の幅寸法も小さくなり、熱変形時に発生する力が抑制される。このため、大きな弾性力によって固定接点と可動接点との間の接触圧力を高める可動片を採用することが困難となり、固定接点と可動接点の間の導通時の電気抵抗が上昇する。 However, in the breaker described in Patent Document 1, when the width dimension of the case is set to be small, the width dimension of the heat responsive element is also reduced, and the force generated during thermal deformation is suppressed. For this reason, it becomes difficult to employ a movable piece that increases the contact pressure between the fixed contact and the movable contact due to a large elastic force, and the electrical resistance when conducting between the fixed contact and the movable contact increases.
　可動片が上記バイメタルによって構成されている形態では、可動片の弾性力を高めた場合、熱変形時に発生する力も同時に高められるので、上記問題は生じにくい。従って、上記問題は、可動片と熱応動素子とが別々の部品により構成されている形態に特有の問題である。 In the form in which the movable piece is composed of the above bimetal, when the elastic force of the movable piece is increased, the force generated during thermal deformation is also increased at the same time, so the above problems do not occur easily. Therefore, the above-mentioned problem is peculiar to the form in which the movable piece and the thermoresponsive element are composed of separate parts.
　本発明は、上記課題を解決するためになされたものであり、導通時の電気抵抗を維持しつつ、小型化を容易に実現できる熱応動素子及びブレーカー等を提供することを主たる目的とする。 The present invention has been made to solve the above problems, and a main object of the present invention is to provide a thermal responsive element, a breaker, and the like that can easily realize miniaturization while maintaining electrical resistance when conducting.
　上記目的を達成するために、本発明の熱応動素子は、板状に形成された熱応動素子であって、厚さ方向から視た平面視で、長さ方向にのびる長辺と、前記長さ方向に垂直な幅方向にのびる短辺とを有する長方形状に形成され、前記長さ方向の中央部に、幅寸法を拡大するための拡幅部が設けられ、前記中央部に向って前記幅寸法が漸増している、ことを特徴とする。 In order to achieve the above-mentioned object, the thermoresponsive element of the present invention is a plate-shaped thermoresponsive element, and has a long side extending in the length direction in a plan view viewed from the thickness direction, and the length. It is formed in a rectangular shape having a short side extending in the width direction perpendicular to the vertical direction, and a widening portion for expanding the width dimension is provided in the central portion in the length direction, and the width toward the central portion. It is characterized in that the dimensions are gradually increasing.
　本発明に係る前記熱応動素子において、前記長辺は、樽形状に肥大している、ことが望ましい。 In the thermoresponsive element according to the present invention, it is preferable that the long side is enlarged in a barrel shape.
　本発明に係る前記熱応動素子において、前記長辺と前記短辺とが交差する角部は、丸み付けされている、ことが望ましい。 In the thermoresponsive element according to the present invention, it is preferable that the corners where the long sides and the short sides intersect are rounded.
　また、本発明のブレーカーは、前記熱応動素子と、固定接点と、弾性変形する弾性部及び該弾性部の先端部に可動接点を有し、前記可動接点を前記固定接点に押圧して接触させる可動片と、前記可動片及び前記熱応動素子を収容するための凹部を有する第１ケースとを備えたブレーカーであって、前記熱応動素子は、温度変化に伴って変形することにより、前記可動片の状態を前記可動接点が前記固定接点に接触する導通状態から前記可動接点が前記固定接点から離隔する遮断状態に移行可能であり、前記第１ケースは、前記凹部の前記幅方向の外側に側壁を有し、前記側壁の厚さは、前記側壁の前記長さ方向の中央部に向って漸減している、ことを特徴とする。 Further, the breaker of the present invention has the thermal responsive element, a fixed contact, an elastic portion that elastically deforms, and a movable contact at the tip of the elastic portion, and presses the movable contact against the fixed contact. A breaker comprising a movable piece and a first case having a recess for accommodating the movable piece and the heat responsive element, wherein the heat responsive element is deformed in accordance with a change in temperature to move the movable piece. It is possible to shift the state of the piece from a conductive state in which the movable contact contacts the fixed contact to a shut-off state in which the movable contact is separated from the fixed contact, and the first case is located outside the recess in the width direction. It has a side wall, and the thickness of the side wall is gradually reduced toward the central portion of the side wall in the longitudinal direction.
　本発明に係る前記ブレーカーにおいて、前記凹部の少なくとも一部を覆う第２ケースをさらに備え、前記第２ケースは、前記側壁の端面と固着される固着面を有し、前記固着面には、前記端面に向って突出し、前記長さ方向に沿って連続する突出部が設けられ、前記突出部は、前記側壁の内側面よりも前記幅方向の外方に形成されている、ことが望ましい。 In the breaker according to the present invention, a second case that covers at least a part of the recess is further provided, the second case has a fixing surface that is fixed to an end surface of the side wall, and the fixing surface has the It is preferable that a projecting portion that projects toward the end surface and that is continuous along the length direction is provided, and that the projecting portion is formed outward of the inner side surface of the side wall in the width direction.
　本発明に係る前記ブレーカーにおいて、前記突出部の前記長さ方向に垂直な断面積は、前記側壁の前記長さ方向の前記中央部に向って減少している、ことが望ましい。 In the breaker according to the present invention, it is preferable that a cross-sectional area of the protrusion that is perpendicular to the length direction decreases toward the central portion of the side wall in the length direction.
　本発明の電気機器用の安全回路は、前記ブレーカーを備えたことを特徴とする。 The safety circuit for electric equipment of the present invention is characterized by including the breaker.
　本発明の電気機器用の２次電池パックは、前記ブレーカーを備えたことを特徴とする。 A secondary battery pack for electric equipment of the present invention is characterized by including the breaker.
　一般に、上記熱変形時に熱応動素子が発生する力は、熱応動素子の厚さ寸法に依存する。しかしながら、本願の発明者は、単に厚さ寸法のみが増大された熱応動素子にあっては、安定した温度特性が得られ難いことに気が付いた。そして、上記発明者は、さらに鋭意研究を重ねた結果、長方形状の熱応動素子において、温度特性の安定化には、長さ方向の中央部の幅寸法が有効に作用することを見い出した。 Generally speaking, the force generated by the thermoresponsive element during the thermal deformation depends on the thickness of the thermoresponsive element. However, the inventor of the present application has noticed that it is difficult to obtain stable temperature characteristics in the thermal responsive element in which only the thickness dimension is increased. As a result of further intensive studies, the inventor has found that in the rectangular thermoresponsive element, the width dimension of the central portion in the length direction effectively acts to stabilize the temperature characteristics.
　すなわち、本発明の熱応動素子によれば、長さ方向の中央部に、幅寸法を拡大するための拡幅部が設けられ、中央部に向って幅寸法が漸増している。これにより、優れた温度特性を安定的に確保しながら、熱応動素子の厚さ寸法を増大させることが可能となり、上記熱変形時に熱応動素子が発生する力を容易に高めることが可能となる。一方、中央部から短辺に向って、熱応動素子の幅寸法が抑制されるので、平面視での熱応動素子の占有面積が抑制され、熱応動素子の小型化が容易に実現される。 That is, according to the thermoresponsive element of the present invention, the widened portion for expanding the width dimension is provided in the central portion in the length direction, and the width dimension is gradually increased toward the central portion. As a result, it is possible to increase the thickness dimension of the heat responsive element while stably ensuring excellent temperature characteristics, and it is possible to easily increase the force generated by the heat responsive element during the thermal deformation. .. On the other hand, since the width dimension of the thermoresponsive element is suppressed from the central portion toward the short side, the occupied area of the thermoresponsive element in a plan view is suppressed, and the miniaturization of the thermoresponsive element is easily realized.
　また、本発明のブレーカーによれば、上記熱応動素子を備えているので、大きな弾性力を発生する可動片を採用することにより、導通時の電気抵抗を容易に低減することが可能となる。また、第１ケースの側壁の厚さが、側壁の長さ方向の中央部に向って漸減しているので、上記熱応動素子とあいまって、ブレーカーの小型化が容易に実現される。 Further, according to the breaker of the present invention, since the thermal responsive element is provided, it is possible to easily reduce the electric resistance during conduction by adopting the movable piece that generates a large elastic force. Moreover, since the thickness of the side wall of the first case is gradually reduced toward the central portion in the length direction of the side wall, the breaker can be easily miniaturized together with the heat responsive element.
本発明の一実施形態によるブレーカーの概略構成を示す組み立て前の斜視図。The perspective view before an assembly showing the schematic structure of the breaker by one embodiment of the present invention. 通常の充電又は放電状態における上記ブレーカーを示す断面図。Sectional drawing which shows the said breaker in a normal charge or discharge state. 過充電状態又は異常時などにおける上記ブレーカーを示す断面図。Sectional drawing which shows the said breaker at the time of an overcharge state or an abnormality. 上記ブレーカーに適用される熱応動素子を示す平面図。The top view which shows the thermoresponsive element applied to the said breaker. 上記熱応動素子の変形例を示す平面図。The top view which shows the modification of the said thermoresponsive element. 上記熱応動素子の別の変形例を示す平面図。The top view which shows another modification of the said thermoresponsive element. 上記熱応動素子のさらに別の変形例を示す平面図。The top view which shows another modification of the said thermoresponsive element. 上記熱応動素子のさらに別の変形例を示す平面図。The top view which shows another modification of the said thermoresponsive element. 上記ブレーカーに適用されるケース本体を示す斜視図。The perspective view which shows the case main body applied to the said breaker. 上記ブレーカーに適用される蓋部材を裏側から視た斜視図。The perspective view which looked at the lid member applied to the above-mentioned breaker from the back side. 本発明の上記ブレーカーを備えた２次電池パックの構成を示す平面図。The top view which shows the structure of the secondary battery pack provided with the said breaker of this invention. 本発明の上記ブレーカーを備えた安全回路の回路図。The circuit diagram of the safety circuit provided with the above-mentioned breaker of the present invention.
　本発明の一実施形態によるブレーカーについて図面を参照して説明する。図１乃至図３は、ブレーカー１の構成を示している。ブレーカー１は、電気機器等に実装され、過度な温度上昇又は過電流から電気機器を保護する。 A breaker according to an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show the configuration of the breaker 1. The breaker 1 is mounted on an electric device or the like and protects the electric device from an excessive temperature rise or an overcurrent.
　ブレーカー１は、固定接点２１を有する固定片２と、先端部に可動接点４１を有する可動片４と、温度変化に伴って変形する熱応動素子５と、ＰＴＣ（Positive Temperature Coefficient）サーミスター６と、固定片２、可動片４、熱応動素子５及びＰＴＣサーミスター６を収容するケース１０等によって構成されている。ケース１０は、ケース本体（第１ケース）７とケース本体７の上面に装着される蓋部材（第２ケース）８等によって構成されている。 The breaker 1 includes a fixed piece 2 having a fixed contact 21, a movable piece 4 having a movable contact 41 at a tip thereof, a thermal responsive element 5 that deforms with a temperature change, and a PTC (Positive Temperature Coefficient) thermistor 6. , The fixed piece 2, the movable piece 4, the thermoresponsive element 5, and the case 10 that houses the PTC thermistor 6. The case 10 includes a case body (first case) 7, a lid member (second case) 8 mounted on the upper surface of the case body 7, and the like.
　固定片２は、例えば、銅等を主成分とする金属板（この他、銅－チタニウム合金、洋白、黄銅などの金属板）をプレス加工することにより形成され、ケース本体７にインサート成形により埋め込まれている。固定片２の一端には外部回路と電気的に接続される端子２２が形成され、他端側には、ＰＴＣサーミスター６を支持する支持部２３が形成されている。ＰＴＣサーミスター６は、固定片２の支持部２３に３箇所形成された凸状の突起（ダボ）２４の上に載置されて、突起２４に支持される。固定片２が階段状に曲げられることにより、固定接点２１と支持部２３とが段違いに配置され、ＰＴＣサーミスター６を収納する空間が容易に確保される。 The fixing piece 2 is formed, for example, by pressing a metal plate containing copper as a main component (other than this, a metal plate of copper-titanium alloy, nickel silver, brass, etc.), and is insert-molded into the case body 7. It is embedded. A terminal 22 that is electrically connected to an external circuit is formed at one end of the fixed piece 2, and a support portion 23 that supports the PTC thermistor 6 is formed at the other end side. The PTC thermistor 6 is mounted on convex protrusions (doughs) 24 formed at three locations on the support portion 23 of the fixed piece 2 and supported by the protrusions 24. By bending the fixed piece 2 in a stepwise manner, the fixed contact 21 and the support portion 23 are arranged in different steps, and a space for accommodating the PTC thermistor 6 is easily secured.
　固定接点２１は、銀、ニッケル、ニッケル－銀合金の他、銅－銀合金、金－銀合金などの導電性の良い材料のクラッド、メッキ又は塗布等により可動接点４１に対向する位置に形成され、ケース本体７の内部に形成されている開口７３ａの一部から露出されている。端子２２はケース本体７の端縁から外側に突き出されている。支持部２３は、ケース本体７の内部に形成されている開口７３ｄから露出されている。 The fixed contact 21 is formed at a position facing the movable contact 41 by clad, plating or coating of a material having good conductivity such as silver, nickel, nickel-silver alloy, copper-silver alloy, gold-silver alloy. It is exposed from a part of the opening 73a formed inside the case body 7. The terminal 22 is projected outward from the edge of the case body 7. The support portion 23 is exposed from an opening 73d formed inside the case body 7.
　本出願においては、特に断りのない限り、固定片２において、固定接点２１が形成されている側の面（すなわち図１において上側の面）をＡ面、その反対側の面をＢ面として説明している。固定接点２１から可動接点４１に向く方向を第１方向と、第１方向とは反対の方向を第２方向とそれぞれ定義した場合、Ａ面は第１方向を向き、Ｂ面は第２方向を向く。他の部品、例えば、可動片４及び熱応動素子５、ＰＴＣサーミスター６等についても同様である。 In the present application, unless otherwise specified, in the fixed piece 2, the surface on the side where the fixed contact 21 is formed (that is, the upper surface in FIG. 1) is the A surface, and the opposite surface is the B surface. is doing. When the direction from the fixed contact 21 to the movable contact 41 is defined as the first direction and the direction opposite to the first direction is defined as the second direction, the A surface faces the first direction and the B surface faces the second direction. Turn. The same applies to other parts such as the movable piece 4, the thermal actuator 5, the PTC thermistor 6 and the like.
　可動片４は、銅等を主成分とする板状の金属材料をプレス加工することにより、長手方向の中心線に対して対称なアーム状に形成されている。 The movable piece 4 is formed into an arm shape symmetrical with respect to the center line in the longitudinal direction by pressing a plate-shaped metal material containing copper or the like as a main component.
　可動片４の長手方向の先端部には、可動接点４１が形成されている。可動接点４１は、例えば、固定接点２１と同等の材料によって形成され、溶接の他、クラッド、かしめ（crimping）等の手法によって可動片４の先端部に接合されている。 A movable contact 41 is formed at the tip of the movable piece 4 in the longitudinal direction. The movable contact 41 is formed of, for example, a material similar to that of the fixed contact 21, and is joined to the tip end of the movable piece 4 by a method such as welding, clad, crimping, or the like.
　可動片４の長手方向の他端部には、外部回路と電気的に接続される端子４２が形成されている。可動片４は、可動接点４１と端子４２の間に、当接部４３及び弾性部４４を有している。当接部４３は、端子４２と弾性部４４との間でケース本体７及び蓋部材８と当接する。当接部４３は、可動片４の短手方向に翼状に突出する突出部４３ａを有する。突出部４３ａが設けられていることにより、当接部４３が幅広く大きな領域でケース本体７及び蓋部材８によって挟み込まれ、可動片４がケース１０に対して強固に固定される。 A terminal 42 electrically connected to an external circuit is formed at the other end of the movable piece 4 in the longitudinal direction. The movable piece 4 has a contact portion 43 and an elastic portion 44 between the movable contact 41 and the terminal 42. The contact portion 43 contacts the case body 7 and the lid member 8 between the terminal 42 and the elastic portion 44. The contact portion 43 has a protruding portion 43a that protrudes like a wing in the lateral direction of the movable piece 4. Since the protrusion 43a is provided, the contact portion 43 is sandwiched between the case body 7 and the lid member 8 in a wide and large area, and the movable piece 4 is firmly fixed to the case 10.
　弾性部４４は、当接部４３から可動接点４１の側に延出されている。可動片４は、弾性部４４の基端側の当接部４３で、ケース１０によって片持ち支持され、その状態で弾性部４４が弾性変形することにより、弾性部４４の先端部に形成されている可動接点４１が固定接点２１の側に押圧されて接触し、固定片２と可動片４とが通電可能となる。 The elastic portion 44 extends from the contact portion 43 to the movable contact 41 side. The movable piece 4 is cantilevered by the case 10 at the abutment portion 43 on the proximal end side of the elastic portion 44, and is elastically deformed in this state to be formed at the tip portion of the elastic portion 44. The movable contact 41 that is present is pressed against the side of the fixed contact 21 and comes into contact with it, and the fixed piece 2 and the movable piece 4 can be energized.
　可動片４は、弾性部４４において、プレス加工により湾曲又は屈曲されている。湾曲又は屈曲の度合いは、熱応動素子５を収納できる限り特に限定はなく、反転動作温度及び正転復帰温度における弾性力、接点の押圧力などを考慮して適宜設定すればよい。また、弾性部４４のＢ面には、熱応動素子５に対向して一対の突起４４ａ，４４ｂが形成されている。突起４４ａは、基端側で熱応動素子５に向って突出し、遮断状態で熱応動素子５と当接する。突起４４ｂは、突起４４ａよりも先端側（すなわち可動接点４１側）で熱応動素子５に向って突出し、遮断状態で熱応動素子５と当接する。過熱により熱応動素子５が変形すると、熱応動素子５が突起４４ａ及び突起４４ｂと当接し、熱応動素子５の変形が突起４４ａ及び突起４４ｂを介して弾性部４４に伝達され、可動片４の先端部が押し上げられる（図３参照）。 The movable piece 4 is curved or bent in the elastic portion 44 by press working. The degree of bending or bending is not particularly limited as long as the thermoresponsive element 5 can be housed therein, and may be appropriately set in consideration of the elastic force at the reversing operation temperature and the normal return temperature, the pressing force of the contacts, and the like. A pair of protrusions 44 a and 44 b is formed on the surface B of the elastic portion 44 so as to face the thermoresponsive element 5. The protrusion 44a protrudes toward the heat responsive element 5 at the base end side and contacts the heat responsive element 5 in a blocked state. The protrusion 44b protrudes toward the heat responsive element 5 on the tip side (that is, the movable contact 41 side) of the protrusion 44a, and contacts the heat responsive element 5 in a blocked state. When the thermal responsive element 5 is deformed by overheating, the thermal responsive element 5 contacts the protrusions 44a and 44b, the deformation of the thermal responsive element 5 is transmitted to the elastic portion 44 via the protrusions 44a and 44b, and the movable piece 4 moves. The tip is pushed up (see Fig. 3).
　熱応動素子５は、可動片４の状態を可動接点４１が固定接点２１に接触する導通状態から可動接点４１が固定接点２１から離隔する遮断状態に移行させる。熱応動素子５は、熱膨張率の異なる薄板材を積層することにより板状に形成され、断面が円弧状に湾曲した初期形状をなしている。過熱により動作温度に達すると、熱応動素子５の湾曲形状は、スナップモーションを伴って逆反りし、冷却により復帰温度を下回ると復元する。熱応動素子５の初期形状は、プレス加工により形成することができる。所期の温度で熱応動素子５の逆反り動作により可動片４の弾性部４４が押し上げられ、かつ弾性部４４の弾性力により元に戻る限り、熱応動素子５の材質及び形状は特に限定されるものでないが、生産性及び逆反り動作の効率性の観点から矩形状が望ましい。 The heat responsive element 5 shifts the state of the movable piece 4 from a conductive state in which the movable contact 41 contacts the fixed contact 21 to a cutoff state in which the movable contact 41 is separated from the fixed contact 21. The heat responsive element 5 is formed in a plate shape by laminating thin plate materials having different thermal expansion coefficients, and has an initial shape in which a cross section is curved in an arc shape. When the operating temperature is reached due to overheating, the curved shape of the thermal responsive element 5 reversely warps with snap motion, and is restored when the temperature falls below the return temperature due to cooling. The initial shape of the thermoresponsive element 5 can be formed by press working. The material and shape of the thermoresponsive element 5 are not particularly limited as long as the elastic portion 44 of the movable piece 4 is pushed up by the backward warping operation of the thermoresponsive element 5 at the desired temperature and returned to its original state by the elastic force of the elastic portion 44. Although not limited, a rectangular shape is desirable from the viewpoint of productivity and efficiency of reverse warping operation.
　熱応動素子５の材料としては、洋白、黄銅、ステンレス鋼等の各種の合金からなる熱膨張率の異なる２種類の材料を積層したものが、所要条件に応じて組み合わせて使用される。例えば、安定した作動温度及び復帰温度が得られる熱応動素子５の材料としては、高膨脹側に銅－ニッケル－マンガン合金、低膨脹側に鉄－ニッケル合金を組み合わせたものが望ましい。また、化学的安定性の観点からさらに望ましい材料として、高膨脹側に鉄－ニッケル－クロム合金、低膨脹側に鉄－ニッケル合金を組み合わせたものが挙げられる。さらにまた、化学的安定性及び加工性の観点からさらに望ましい材料として、高膨脹側に鉄－ニッケル－クロム合金、低膨脹側に鉄－ニッケル－コバルト合金を組み合わせたものが挙げられる。 As the material of the heat-responsive element 5, two kinds of materials having different coefficients of thermal expansion, which are made of various alloys such as nickel silver, brass and stainless steel, are laminated and used in combination according to the required conditions. For example, as a material of the thermoresponsive element 5 that can obtain a stable operation temperature and a stable return temperature, it is desirable to combine a copper-nickel-manganese alloy on the high expansion side and an iron-nickel alloy on the low expansion side. Further, as a more desirable material from the viewpoint of chemical stability, a material in which an iron-nickel-chromium alloy is combined on the high expansion side and an iron-nickel alloy is combined on the low expansion side can be mentioned. Further, as a more desirable material from the viewpoint of chemical stability and workability, there is a combination of an iron-nickel-chromium alloy on the high expansion side and an iron-nickel-cobalt alloy on the low expansion side.
　ＰＴＣサーミスター６は、可動片４が遮断状態にあるとき、固定片２と可動片４とを導通させる。ＰＴＣサーミスター６は、固定片２と熱応動素子５との間に配設されている。すなわち、ＰＴＣサーミスター６を挟んで、固定片２の支持部２３は熱応動素子５の直下に位置している。熱応動素子５の逆反り動作により固定片２と可動片４との通電が遮断されたとき、ＰＴＣサーミスター６に流れる電流が増大する。ＰＴＣサーミスター６は、温度上昇と共に抵抗値が増大して電流を制限する正特性サーミスターであれば、作動電流、作動電圧、作動温度、復帰温度などの必要に応じて種類を選択でき、その材料及び形状はこれらの諸特性を損なわない限り特に限定されるものではない。本実施形態では、チタニウム酸バリウム、チタニウム酸ストロンチウム又はチタニウム酸カルシウムを含むセラミック焼結体が用いられる。セラミック焼結体の他、ポリマーにカーボン等の導電性粒子を含有させたいわゆるポリマーＰＴＣを用いてもよい。 The PTC thermistor 6 makes the fixed piece 2 and the movable piece 4 electrically conductive when the movable piece 4 is in the cutoff state. The PTC thermistor 6 is arranged between the fixed piece 2 and the thermoresponsive element 5. That is, the support portion 23 of the fixed piece 2 is located immediately below the thermoresponsive element 5 with the PTC thermistor 6 interposed therebetween. When the reverse movement of the thermal actuator 5 cuts off the current flow between the fixed piece 2 and the movable piece 4, the current flowing through the PTC thermistor 6 increases. If the PTC thermistor 6 is a positive temperature coefficient thermistor in which the resistance value increases as the temperature rises and limits the current, the type can be selected according to the needs of the operating current, the operating voltage, the operating temperature, the return temperature, etc. The material and shape are not particularly limited as long as these characteristics are not impaired. In this embodiment, a ceramic sintered body containing barium titanate, strontium titanate or calcium titanate is used. In addition to the ceramic sintered body, so-called polymer PTC in which conductive particles such as carbon are contained in polymer may be used.
　ケース１０を構成するケース本体７及び蓋部材８は、難燃性のポリアミド、耐熱性に優れたポリフェニレンサルファイド（ＰＰＳ）、液晶ポリマー（ＬＣＰ）、ポリブチレンテレフタレート（ＰＢＴ）などの熱可塑性樹脂により成形されている。上述した樹脂と同等以上の特性が得られるのであれば、樹脂以外の材料を適用してもよい。 The case body 7 and the lid member 8 constituting the case 10 are made of a thermoplastic resin such as flame-retardant polyamide, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polybutylene terephthalate (PBT) having excellent heat resistance. Has been done. A material other than the resin may be applied as long as the characteristics equal to or higher than those of the resin described above can be obtained.
　ケース本体７には、可動片４、熱応動素子５及びＰＴＣサーミスター６などを収容するための内部空間である凹部７３が形成されている。凹部７３は、可動片４を収容するための開口７３ａ，７３ｂ、可動片４及び熱応動素子５を収容するための開口７３ｃ、並びに、ＰＴＣサーミスター６を収容するための開口７３ｄ等を有している。なお、ケース本体７に組み込まれた可動片４、熱応動素子５の端縁は、凹部７３を構成する枠によってそれぞれ当接され、熱応動素子５の逆反り時に案内される。 The case main body 7 is formed with a recess 73 which is an internal space for housing the movable piece 4, the thermoresponsive element 5, the PTC thermistor 6, and the like. The recess 73 has openings 73a and 73b for accommodating the movable piece 4, an opening 73c for accommodating the movable piece 4 and the thermoresponsive element 5, an opening 73d for accommodating the PTC thermistor 6, and the like. ing. The edges of the movable piece 4 and the heat responsive element 5 incorporated in the case body 7 are respectively brought into contact with each other by the frame forming the recess 73 and guided when the heat responsive element 5 warps backward.
　蓋部材８は、凹部７３を覆うように構成されている。蓋部材８は、凹部７３の少なくとも一部を覆う形態であってもよい。蓋部材８には、銅等を主成分とする金属板又はステンレス鋼等の金属板がインサート成形によって埋め込まれていてもよい。金属板は、可動片４のＡ面と適宜当接し、可動片４の動きを規制すると共に、蓋部材８のひいては筐体としてのケース１０の剛性・強度を高めつつブレーカー１の小型化に貢献する。 The lid member 8 is configured to cover the recess 73. The lid member 8 may be configured to cover at least a part of the recess 73. A metal plate containing copper or the like as a main component or a metal plate such as stainless steel may be embedded in the lid member 8 by insert molding. The metal plate appropriately contacts the surface A of the movable piece 4 to restrict the movement of the movable piece 4, and contributes to the downsizing of the breaker 1 while enhancing the rigidity and strength of the lid member 8 and thus the case 10 as a housing. To do.
　図１が示すように、固定片２、可動片４、熱応動素子５及びＰＴＣサーミスター６等を収容したケース本体７の開口７３ａ、７３ｂ、７３ｃ等を塞ぐように、蓋部材８が、ケース本体７に装着される。ケース本体７と蓋部材８とは、例えば超音波溶着によって接合される。 As shown in FIG. 1, the lid member 8 covers the case 73 so as to close the openings 73a, 73b, 73c and the like of the case body 7 that houses the fixed piece 2, the movable piece 4, the thermoresponsive element 5, the PTC thermistor 6 and the like. It is attached to the main body 7. The case body 7 and the lid member 8 are joined by ultrasonic welding, for example.
　図２及び３は、ブレーカー１の動作の概略を示している。図２は、通常の充電又は放電状態におけるブレーカー１の動作を示している。通常の充電又は放電状態においては、熱応動素子５は逆反り前の初期形状を維持している。弾性部４４によって可動接点４１が固定接点２１の側に押圧されることにより、可動接点４１と固定接点２１とが接触し、ブレーカー１の固定片２と可動片４とが導通可能な状態とされる。 2 and 3 show the outline of the operation of the breaker 1. FIG. 2 shows the operation of the breaker 1 in a normal charging or discharging state. In a normal charge or discharge state, the thermoresponsive element 5 maintains the initial shape before reverse warpage. When the movable contact 41 is pressed toward the fixed contact 21 by the elastic portion 44, the movable contact 41 and the fixed contact 21 come into contact with each other, and the fixed piece 2 and the movable piece 4 of the breaker 1 are brought into a conductive state. It
　図２に示されるように、熱応動素子５は、導通状態の可動片４の突起４４ａ及び突起４４ｂと離隔していてもよい。これにより、可動接点４１と固定接点２１との接触圧力が高められ、両者間の接触抵抗が低減される。 As shown in FIG. 2, the thermal responsive element 5 may be separated from the protrusions 44a and 44b of the movable piece 4 in the conductive state. As a result, the contact pressure between the movable contact 41 and the fixed contact 21 is increased, and the contact resistance between them is reduced.
　図３は、過充電状態又は異常時などにおけるブレーカー１の動作を示している。過充電又は異常により高温状態となると、動作温度に達した熱応動素子５は逆反りして可動片４の弾性部４４と接触し、弾性部４４が押し上げられて固定接点２１と可動接点４１とが離隔する。このとき、固定接点２１と可動接点４１の間を流れていた電流は遮断される。一方、熱応動素子５は、可動片４と接触して、僅かな漏れ電流が熱応動素子５及びＰＴＣサーミスター６を通して流れることとなる。すなわち、ＰＴＣサーミスター６は、可動片４を遮断状態に移行させている熱応動素子５を介して、固定片２と可動片４とを導通させる。ＰＴＣサーミスター６は、このような漏れ電流の流れる限り発熱を続け、熱応動素子５を逆反り状態に維持させつつ抵抗値を激増させるので、電流は固定接点２１と可動接点４１の間の経路を流れず、上述の僅かな漏れ電流のみが存在する（自己保持回路を構成する）。この漏れ電流は安全装置の他の機能に充てることができる。 FIG. 3 shows the operation of the breaker 1 in the overcharged state or the abnormal state. When it becomes a high temperature state due to overcharging or abnormality, the thermal responsive element 5 that has reached the operating temperature warps backward and contacts the elastic portion 44 of the movable piece 4, and the elastic portion 44 is pushed up to cause the fixed contact 21 and the movable contact 41 to contact each other. Are separated. At this time, the current flowing between the fixed contact 21 and the movable contact 41 is cut off. On the other hand, the thermoresponsive element 5 comes into contact with the movable piece 4, and a slight leakage current flows through the thermoresponsive element 5 and the PTC thermistor 6. That is, the PTC thermistor 6 brings the fixed piece 2 and the movable piece 4 into conduction with each other via the thermal responsive element 5 that moves the movable piece 4 to the cutoff state. The PTC thermistor 6 continues to generate heat as long as such a leakage current flows, and dramatically increases the resistance value while maintaining the thermoresponsive element 5 in the reverse warped state, so that the current passes through the path between the fixed contact 21 and the movable contact 41. Does not flow through and there is only the above-mentioned slight leakage current (constituting a self-holding circuit). This leakage current can be used for other functions of the safety device.
　過充電状態を解除し、又は異常状態を解消すると、ＰＴＣサーミスター６の発熱も収まり、熱応動素子５は復帰温度に戻り、元の初期形状に復元する。そして、可動片４の弾性部４４の弾性力によって可動接点４１と固定接点２１とは再び接触し、回路は遮断状態を解かれ、図２に示す導通状態に復帰する。 When the overcharged state is released or the abnormal state is resolved, the heat generated by the PTC thermistor 6 also subsides, and the thermoresponsive element 5 returns to the return temperature and restores the original initial shape. Then, the elastic force of the elastic portion 44 of the movable piece 4 causes the movable contact 41 and the fixed contact 21 to come into contact with each other again, the circuit is released from the disconnected state, and the conductive state shown in FIG. 2 is restored.
　図４は、熱応動素子５をその厚さ方向から視た平面視である。熱応動素子５は、長さ方向（長手方向）Ｄ１にのびる長辺５１と、長さ方向に垂直な幅方向（短手方向）Ｄ２にのびる短辺５２とを有する長方形状に形成されている。本実施形態のブレーカー１では、可動片４の弾性部４４は、熱応動素子５の長さ方向Ｄ１にのびている。熱応動素子５の長さ方向Ｄ１の中央部５３には、幅寸法を拡大するための拡幅部５４が設けられる。図４において、拡幅部５４は、ハッチングが施された領域で表される（以下、図５等においても同様）。 FIG. 4 is a plan view of the thermoresponsive element 5 viewed from its thickness direction. The thermoresponsive element 5 is formed in a rectangular shape having a long side 51 extending in the length direction (longitudinal direction) D1 and a short side 52 extending in the width direction (shorter direction) D2 perpendicular to the length direction. .. In the breaker 1 of this embodiment, the elastic portion 44 of the movable piece 4 extends in the length direction D1 of the thermoresponsive element 5. A widened portion 54 for widening the width dimension is provided in the central portion 53 of the heat responsive element 5 in the length direction D1. In FIG. 4, the widened portion 54 is represented by a hatched region (hereinafter, the same applies to FIG. 5 and the like).
　既に述べたように、熱変形時に熱応動素子５が発生する力は、熱応動素子５の厚さ寸法に依存するが、単に厚さ寸法のみが増大された熱応動素子にあっては、安定した温度特性が得られ難い場合がある。そうしたところ、特に長方形状の熱応動素子５においては、温度特性の安定化には中央部５３の幅寸法Ｗ１が有効に作用することが本願発明者によって見い出された。 As described above, the force generated by the thermal response element 5 during thermal deformation depends on the thickness dimension of the thermal response element 5. However, in the thermal response element in which only the thickness dimension is increased, it is stable. It may be difficult to obtain the desired temperature characteristics. In this regard, the inventors of the present application have found that the width dimension W1 of the central portion 53 effectively acts to stabilize the temperature characteristics particularly in the rectangular thermoresponsive element 5.
　本発明の熱応動素子５では、中央部５３に拡幅部５４が設けられていることにより、中央部５３の幅寸法Ｗ１は、長さ方向Ｄ１の端縁部の幅寸法（短辺５２の長さ）Ｗ２よりも大きい。これにより、優れた温度特性を安定的に確保しながら、熱応動素子５の厚さ寸法を増大させることが可能となり、上記熱変形時に熱応動素子５が発生する力を容易に高めることが可能となる。 In the heat responsive element 5 of the present invention, since the widened portion 54 is provided in the central portion 53, the width dimension W1 of the central portion 53 is the width dimension of the end edge portion in the length direction D1 (the length of the short side 52). It's bigger than W2. As a result, it is possible to increase the thickness dimension of the thermal responsive element 5 while stably securing excellent temperature characteristics, and it is possible to easily increase the force generated by the thermal responsive element 5 during the thermal deformation. Becomes
　さらに、本発明の熱応動素子５では、短辺５２から中央部５３に向って幅寸法が漸増していることにより、熱応動素子５の長さ方向Ｄ１での応力分布が平滑化され、長さ方向Ｄ１の温度特性がより一層安定する。 Furthermore, in the thermoresponsive element 5 of the present invention, the width dimension gradually increases from the short side 52 toward the central portion 53, so that the stress distribution in the longitudinal direction D1 of the thermoresponsive element 5 is smoothed, and The temperature characteristic in the depth direction D1 is further stabilized.
　一方、熱応動素子５の中央部５３から短辺５２に向って、熱応動素子５の幅寸法が抑制されるので、平面視での熱応動素子５の占有面積が抑制され、熱応動素子５の小型化が容易に実現される。 On the other hand, since the width dimension of the thermal response element 5 is suppressed from the central portion 53 of the thermal response element 5 toward the short side 52, the area occupied by the thermal response element 5 in a plan view is suppressed, and the thermal response element 5 is suppressed. Can be easily realized.
　なお、熱応動素子５の中央部５３とは、熱応動素子５の熱変形時において、大きな応力を発生する領域であって、例えば、熱応動素子５の長さ方向Ｄ１の中心からＷ２／４以下の領域である。 The central portion 53 of the thermal responsive element 5 is a region in which a large stress is generated when the thermal responsive element 5 is thermally deformed, and is, for example, W2 / 4 from the center of the thermal responsive element 5 in the length direction D1. The areas are as follows:
　本実施形態では、熱応動素子５の長辺５１は、樽形状に肥大して形成されている。換言すると、熱応動素子５は、幅方向Ｄ２の端縁において、中央部５３が肥大する円弧状の輪郭５６を有する。ここで「円弧」とは、真円の円周の一部のみならず楕円の円周の一部を含む概念である。このような熱応動素子５により、中央部５３から短辺５２に向って熱応動素子５の幅寸法を抑制しつつ、熱変形時に中央部５３にて効率よく応力を発生させることが可能となる。 In the present embodiment, the long side 51 of the thermoresponsive element 5 is enlarged and formed in a barrel shape. In other words, the thermoresponsive element 5 has an arc-shaped contour 56 in which the central portion 53 is enlarged at the end edge in the width direction D2. Here, the “arc” is a concept including not only a part of the circumference of a perfect circle but also a part of the circumference of an ellipse. With such a thermal responsive element 5, it becomes possible to efficiently generate stress in the central portion 53 during thermal deformation while suppressing the width dimension of the thermal responsive element 5 from the central portion 53 toward the short side 52. ..
　図５は、熱応動素子５の変形例である熱応動素子５Ａを示している。熱応動素子５Ａは、長辺５１が直線によって構成されている点で、上記長辺５１が幅方向Ｄ２の外側に向って凸な曲線状に形成されている熱応動素子５と相違する。熱応動素子５Ａでは、長さ方向Ｄ１に対して傾斜する一対の直線と長さ方向Ｄ１に平行な直線によって長辺５１が構成されているが、熱応動素子５Ａでは、中央部５３の長さ方向Ｄ１に平行な直線が省かれていてもよい。熱応動素子５Ａにおいても、中央部５３に拡幅部５４が設けられることにより、優れた温度特性を安定的に確保しながら、熱応動素子５Ａの厚さ寸法を増大させることが可能である点は、熱応動素子５と同様である。 FIG. 5 shows a thermoresponsive element 5A which is a modified example of the thermoresponsive element 5. The thermal responsive element 5A differs from the thermal responsive element 5 in that the long side 51 is formed by a straight line, and the long side 51 is formed in a curved shape that is convex outward in the width direction D2. In the heat responsive element 5A, the long side 51 is composed of a pair of straight lines inclined with respect to the length direction D1 and a straight line parallel to the length direction D1. A straight line parallel to the direction D1 may be omitted. Also in the heat responsive element 5A, by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the heat responsive element 5A while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
　図６は、熱応動素子５の別の変形例である熱応動素子５Ｂを示している。熱応動素子５Ｂは、長辺５１が幅方向Ｄ２の内側に向って凸な曲線状に形成されている点で、熱応動素子５と相違する。熱応動素子５Ｂにおいても、中央部５３に拡幅部５４が設けられることにより、優れた温度特性を安定的に確保しながら、熱応動素子５Ｂの厚さ寸法を増大させることが可能である点は、熱応動素子５と同様である。 FIG. 6 shows a thermoresponsive element 5B which is another modification of the thermoresponsive element 5. The thermal responsive element 5B differs from the thermal responsive element 5 in that the long side 51 is formed in a curved shape that is convex inward in the width direction D2. Also in the thermal responsive element 5B, by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the thermal responsive element 5B while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
　図７は、熱応動素子５のさらに別の変形例である熱応動素子５Ｃを示している。熱応動素子５Ｃは、拡幅部５４が中央部５３のみに形成されている点で、拡幅部５４が中央部５３から短辺５２にわたって形成されている熱応動素子５と相違する。熱応動素子５Ｃにおいても、中央部５３に拡幅部５４が設けられることにより、優れた温度特性を安定的に確保しながら、熱応動素子５Ｃの厚さ寸法を増大させることが可能である点は、熱応動素子５と同様である。 FIG. 7 shows a heat responsive element 5C which is another modification of the heat responsive element 5. The thermal response element 5C is different from the thermal response element 5 in which the widened portion 54 is formed from the central portion 53 to the short side 52 in that the widened portion 54 is formed only in the central portion 53. Also in the heat responsive element 5C, by providing the widened portion 54 in the central portion 53, it is possible to increase the thickness dimension of the heat responsive element 5C while stably securing excellent temperature characteristics. The same as the thermoresponsive element 5.
　図８は、熱応動素子５のさらに別の変形例である熱応動素子５Ｄを示している。熱応動素子５Ｄは、長辺５１と短辺５２とが交差する角部５５が丸み付けされている点で、熱応動素子５と相違する。熱応動素子５Ａ乃至５Ｃにおいて、角部５５が丸み付けされていてもよい。また、角部５５は、直線状に面取りされていてもよい。角部５５が丸み付け等されることにより、熱応動素子５Ｄがケース本体７の凹部７３に収容される際、角部５５の引っ掛かりが抑制され、熱応動素子５Ｄが円滑に収容される。 FIG. 8 shows a heat responsive element 5D which is another modification of the heat responsive element 5. The heat responsive element 5D is different from the heat responsive element 5 in that the corner 55 where the long side 51 and the short side 52 intersect is rounded. In the heat responsive elements 5A to 5C, the corner 55 may be rounded. Further, the corner portion 55 may be chamfered linearly. By rounding the corner portions 55, when the heat responsive element 5D is housed in the recess 73 of the case body 7, the corner portion 55 is prevented from being caught and the heat responsive element 5D is smoothly housed.
　図１に示される本発明のブレーカー１によれば、上記熱応動素子５乃至５Ｄのいずれかを備えているので、大きな弾性力を発生する可動片４を採用することにより、導通時の電気抵抗を容易に低減することが可能となる。 According to the breaker 1 of the present invention shown in FIG. 1, since any one of the heat responsive elements 5 to 5D is provided, by adopting the movable piece 4 that generates a large elastic force, the electrical resistance at the time of conduction is increased. Can be easily reduced.
　図９は、固定片２がインサート成形されたケース本体７を示している。ケース本体７は、凹部７３の幅方向Ｄ２の外側に側壁７６を有している。側壁７６は、熱応動素子５の長さ方向Ｄ１に沿ってのびている。側壁７６の厚さＴは、側壁７６の長さ方向Ｄ１の中央部７７に向って漸減している。これにより、熱応動素子５をブレーカー１に適用することに伴い、側壁７６の中央部７７が幅方向Ｄ２に肥大することが抑制され、ブレーカー１の小型化が容易に実現される。 FIG. 9 shows the case body 7 in which the fixing piece 2 is insert-molded. The case body 7 has a side wall 76 outside the recess 73 in the width direction D2. The side wall 76 extends along the length direction D1 of the thermoresponsive element 5. The thickness T of the side wall 76 gradually decreases toward the central portion 77 of the side wall 76 in the length direction D1. As a result, it is possible to prevent the central portion 77 of the side wall 76 from being enlarged in the width direction D2 when the thermal actuator 5 is applied to the breaker 1, and the breaker 1 can be easily miniaturized.
　ケース本体７１は、蓋部材８と固着される固着面７５を有している。固着面７５は、凹部７３の周囲を取り囲むように形成されている。側壁７６の端面７８は、蓋部材８と固着され、固着面７５の一部を構成する。 The case body 71 has a fixing surface 75 that is fixed to the lid member 8. The fixing surface 75 is formed so as to surround the periphery of the recess 73. The end surface 78 of the side wall 76 is fixed to the lid member 8 and constitutes a part of the fixed surface 75.
　図１０は、蓋部材８のＢ面を示している。蓋部材８は、ケース本体７の固着面７５と固着される固着面８１を有している。固着面８１は、少なくとも、固着面７５に対向する領域に形成されている。固着面８１は、側壁７６の端面７８と対向する領域８２で端面７８と固着される。固着面８１の領域８２には、端面７８に向って突出する突出部８３が設けられている。図１０では、突出部８３の一部が破断されている。 FIG. 10 shows the B side of the lid member 8. The lid member 8 has a fixing surface 81 that is fixed to the fixing surface 75 of the case body 7. The fixing surface 81 is formed at least in a region facing the fixing surface 75. The fixing surface 81 is fixed to the end surface 78 in the region 82 that faces the end surface 78 of the side wall 76. The area 82 of the fixing surface 81 is provided with a protruding portion 83 that protrudes toward the end surface 78. In FIG. 10, a part of the protruding portion 83 is broken.
　固着面８１に突出部８３が設けられることにより、ケース本体７に蓋部材８が装着されたとき、最初に突出部８３の頂部が固着面７５に当接する。これにより、超音波溶着の際に突出部８３の頂部に作用する圧力が高まり、突出部８３の頂部と固着面７５との間で発生する摩擦熱が増加する。その結果、突出部８３の樹脂が容易に溶融し、固着面７５と固着面８１との固着が良好となる。 By providing the protruding portion 83 on the fixing surface 81, the top of the protruding portion 83 first comes into contact with the fixing surface 75 when the lid member 8 is attached to the case body 7. As a result, the pressure acting on the top of the protrusion 83 during ultrasonic welding increases, and the frictional heat generated between the top of the protrusion 83 and the fixing surface 75 increases. As a result, the resin of the protruding portion 83 is easily melted, and the fixing between the fixing surface 75 and the fixing surface 81 becomes good.
　突出部８３は、側壁７６に沿って長さ方向Ｄ１に連続してのびている。これにより、側壁７６の端面７８と固着面８１との固着が良好となる。さらに、突出部８３は、側壁７６の内側面７９（図９参照）よりも幅方向Ｄ２の外方に形成されている。これにより、溶融した突出部８３の樹脂が凹部７３に侵入し、熱応動素子５と干渉することが抑制される。 The protrusion 83 extends continuously along the side wall 76 in the length direction D1. As a result, the adhesion between the end surface 78 of the side wall 76 and the fixing surface 81 becomes good. Further, the protruding portion 83 is formed outward of the inner side surface 79 (see FIG. 9) of the side wall 76 in the width direction D2. As a result, the melted resin of the protruding portion 83 is prevented from entering the concave portion 73 and interfering with the thermoresponsive element 5.
　突出部８３の長さ方向Ｄ１に垂直な断面積Ｓは、側壁７６の長さ方向Ｄ１の中央部７７に向って減少しているのが望ましい。これにより、溶融した突出部８３の樹脂が、ばりとなって凹部７３に侵入し、熱応動素子５と干渉することがより一層抑制される。また、溶融した突出部８３の樹脂が、ばりとなってケース１０の外側面からはみ出すことが抑制される。 The cross-sectional area S of the protrusion 83 perpendicular to the length direction D1 is preferably reduced toward the central portion 77 of the side wall 76 in the length direction D1. As a result, the molten resin of the protruding portion 83 is further suppressed from entering the concave portion 73 as a flash and interfering with the thermoresponsive element 5. Further, the melted resin of the protruding portion 83 is suppressed from becoming a flash and protruding from the outer side surface of the case 10.
　本実施形態では、突出部８３の内端縁は、側壁７６の内側面７９に沿って形成され、突出部８３の外端縁は、蓋部材８の外縁に沿って平行に形成されている。これにより、突出部８３の幅寸法Ｗ３は、中央部７７に向って減少し、上述した断面積Ｓの分布が容易に実現される。 In the present embodiment, the inner edge of the protruding portion 83 is formed along the inner side surface 79 of the side wall 76, and the outer edge of the protruding portion 83 is formed parallel to the outer edge of the lid member 8. As a result, the width dimension W3 of the protruding portion 83 decreases toward the central portion 77, and the above-described distribution of the cross-sectional area S is easily realized.
　本発明のブレーカー１は、上記実施形態の構成に限られることなく、種々の態様に変更して実施されうる。すなわち、熱応動素子５等は、少なくとも、板状に形成され、厚さ方向から視た平面視で、長さ方向Ｄ１にのびる長辺５１と、長さ方向Ｄ１に垂直な幅方向Ｄ２にのびる短辺５２とを有する長方形状に形成され、長さ方向Ｄ１の中央部５３に、幅寸法を拡大するための拡幅部５４が設けられることにより、中央部５３に向って幅寸法が漸増していればよい。 The breaker 1 of the present invention is not limited to the configuration of the above embodiment, and may be implemented in various modes. That is, the heat responsive element 5 and the like are formed at least in a plate shape and extend in the plan view viewed from the thickness direction in the long side 51 extending in the length direction D1 and in the width direction D2 perpendicular to the length direction D1. The width dimension is gradually increased toward the central portion 53 by forming the rectangular portion having the short side 52 and the widening portion 54 for enlarging the width dimension in the central portion 53 in the length direction D1. Just do it.
　例えば、ケース本体７と蓋部材８との接合手法は、超音波溶着に限られることなく、両者が強固に接合される手法であれば、適宜適用することができる。例えば、液状又はゲル状の接着剤を塗布・充填し、硬化させることにより、両者が接着されてもよい。また、ケース１０は、ケース本体７と蓋部材８等によって構成される形態に限られることなく、２個以上の部品によって構成されていればよい。 For example, the method of joining the case body 7 and the lid member 8 is not limited to ultrasonic welding, and any method can be appropriately applied as long as the method can firmly join the two. For example, a liquid or gel adhesive may be applied / filled and cured to bond the two. Further, the case 10 is not limited to the form formed by the case body 7, the lid member 8 and the like, and may be formed by two or more parts.
　また、本発明は、例えば、特開２０１６－３５８２２号公報に示されるような、可動片と端子片とが別々に成形され、溶接等によって電気的に接続される形態にも適用することができる。また、本発明は、端子２２及び４２がケース本体７のＢ面から露出している形態にも適用することができる。 Further, the present invention can also be applied to a mode in which a movable piece and a terminal piece are separately molded and electrically connected by welding or the like, for example, as disclosed in JP-A-2016-35822. .. The present invention can also be applied to a form in which the terminals 22 and 42 are exposed from the B surface of the case body 7.
　また、蓋部材８には、開口が設けられていてもよい。開口は、蓋部材８を厚さ方向に貫通する。開口が設けられることにより、遮断状態での可動片４の先端部が蓋部材８に干渉することが抑制され、固定接点２１と可動接点４１との距離（接点ギャップ）の拡大に寄与する。 Also, the lid member 8 may be provided with an opening. The opening penetrates the lid member 8 in the thickness direction. By providing the opening, it is possible to prevent the tip portion of the movable piece 4 in the cutoff state from interfering with the lid member 8 and contribute to the expansion of the distance (contact gap) between the fixed contact 21 and the movable contact 41.
　さらにまた、本発明は、ケース１０から蓋部材８が省かれる形態、すなわち、ケース本体７の凹部７３が開放され、可動片４等が露出する形態にも適用可能である。このような形態では、可動片４が遮断状態にあるときの固定接点２１と可動接点４１との距離がより一層容易に拡大されうる。なお、かかる形態では、上記特開２０１６－３５８２２号公報に示されように、端子片は、ケース本体７にインサート成形され、可動片４は、その基端側で端子片に溶接等されることにより、固定されていてもよい。 Furthermore, the present invention can be applied to a form in which the lid member 8 is omitted from the case 10, that is, a form in which the recess 73 of the case body 7 is opened and the movable piece 4 and the like are exposed. In such a form, the distance between the fixed contact 21 and the movable contact 41 when the movable piece 4 is in the cutoff state can be increased more easily. In this embodiment, the terminal piece is insert-molded in the case body 7, and the movable piece 4 is welded to the terminal piece at the base end side thereof, as disclosed in JP-A-2016-35822. May be fixed by.
　本実施形態では、ＰＴＣサーミスター６による自己保持回路を有しているが、このような構成を省いた形態であっても適用可能である。 In this embodiment, the PTC thermistor 6 has a self-holding circuit, but it is also applicable to a form in which such a configuration is omitted.
　また、本発明のブレーカー１は、２次電池パック、電気機器用の安全回路等にも広く適用できる。図１１は２次電池パック５００を示す。２次電池パック５００は、２次電池５０１と、２次電池５０１の出力回路中に設けたブレーカー１とを備える。図１２は電気機器用の安全回路５０２を示す。安全回路５０２は２次電池５０１の出力回路中に直列にブレーカー１を備えている。ブレーカー１を備えた２次電池パック５００又は安全回路５０２によれば、導通時の電気抵抗を維持しつつ、小型化を容易に実現できる２次電池パック５００又は安全回路５０２を製造できる。 Also, the breaker 1 of the present invention can be widely applied to secondary battery packs, safety circuits for electric devices, and the like. FIG. 11 shows a secondary battery pack 500. The secondary battery pack 500 includes a secondary battery 501 and a breaker 1 provided in the output circuit of the secondary battery 501. FIG. 12 shows a safety circuit 502 for electrical equipment. The safety circuit 502 includes the breaker 1 in series in the output circuit of the secondary battery 501. According to the secondary battery pack 500 or the safety circuit 502 provided with the breaker 1, it is possible to manufacture the secondary battery pack 500 or the safety circuit 502 that can easily realize downsizing while maintaining the electrical resistance when conducting.
１　　　：ブレーカー
２　　　：固定片
４　　　：可動片
５　　　：熱応動素子
７　　　：ケース本体（第１ケース）
８　　　：蓋部材（第２ケース）
２１　　：固定接点
４１　　：可動接点
４４　　：弾性部
５１　　：長辺
５２　　：短辺
５３　　：中央部
５４　　：拡幅部
５５　　：角部
７３　　：凹部
７６　　：側壁
７７　　：中央部
７８　　：端面
７９　　：内側面
８１　　：固着面
８３　　：突出部
５０１　：２次電池
５０２　：安全回路
Ｄ１　　：長さ方向
Ｄ２　　：幅方向
Ｗ　　　：幅寸法 1: Breaker 2: Fixed piece 4: Movable piece 5: Thermal actuator 7: Case body (first case)
8: Lid member (second case)
21: fixed contact 41: movable contact 44: elastic portion 51: long side 52: short side 53: central portion 54: widened portion 55: corner portion 73: recessed portion 76: side wall 77: central portion 78: end surface 79: inner surface 81 : Fixed surface 83: Projection part 501: Secondary battery 502: Safety circuit D1: Length direction D2: Width direction W: Width dimension

Claims (8)

  1. 　板状に形成された熱応動素子であって、
    　厚さ方向から視た平面視で、
    　　長さ方向にのびる長辺と、前記長さ方向に垂直な幅方向にのびる短辺とを有する長方形状に形成され、
    　　前記長さ方向の中央部に、幅寸法を拡大するための拡幅部が設けられ、
    　　　前記中央部に向って前記幅寸法が漸増している、
    　ことを特徴とする熱応動素子。     A heat-responsive element formed in a plate shape,
    In a plan view seen from the thickness direction,
    Formed in a rectangular shape having a long side extending in the length direction and a short side extending in the width direction perpendicular to the length direction,
    The central portion in the length direction is provided with a widened portion for widening the width dimension,
    The width dimension is gradually increased toward the central portion,
    A thermo-responsive element characterized in that
  2. 　前記長辺は、樽形状に肥大している、請求項１記載の熱応動素子。 The thermoresponsive element according to claim 1, wherein the long side is enlarged in a barrel shape.
  3. 　前記長辺と前記短辺とが交差する角部は、丸み付けされている、請求項１又は２に記載の熱応動素子。 The thermal response element according to claim 1 or 2, wherein a corner portion where the long side and the short side intersect is rounded.
  4. 　請求項１乃至３のいずれかに記載の熱応動素子と、
    　固定接点と、
    　弾性変形する弾性部及び該弾性部の先端部に可動接点を有し、前記可動接点を前記固定接点に押圧して接触させる可動片と、
    　前記可動片及び前記熱応動素子を収容するための凹部を有する第１ケースとを備えたブレーカーであって、
    　前記熱応動素子は、温度変化に伴って変形することにより、前記可動片の状態を前記可動接点が前記固定接点に接触する導通状態から前記可動接点が前記固定接点から離隔する遮断状態に移行可能であり、
    　前記第１ケースは、前記凹部の前記幅方向の外側に側壁を有し、
    　前記側壁の厚さは、前記側壁の前記長さ方向の中央部に向って漸減している、
    　ことを特徴とするブレーカー。     A thermal responsive element according to any one of claims 1 to 3,
    Fixed contact,
    An elastic portion that elastically deforms and a movable contact at the tip of the elastic portion, and a movable piece that presses the movable contact against the fixed contact to make contact
    A breaker comprising: a first case having a recess for accommodating the movable piece and the thermoresponsive element,
    By deforming with the temperature change, the heat responsive element can shift the state of the movable piece from a conductive state where the movable contact contacts the fixed contact to a cutoff state where the movable contact separates from the fixed contact. And
    The first case has a side wall outside the recess in the width direction,
    The thickness of the side wall is gradually reduced toward the central portion of the side wall in the longitudinal direction,
    A breaker characterized by that.
  5. 　前記凹部の少なくとも一部を覆う第２ケースをさらに備え、
    　前記第２ケースは、前記側壁の端面と固着される固着面を有し、
    　前記固着面には、前記端面に向って突出し、前記長さ方向に沿って連続する突出部が設けられ、
    　前記突出部は、前記側壁の内側面よりも前記幅方向の外方に形成されている、請求項４記載のブレーカー。     A second case that covers at least a part of the recess,
    The second case has a fixing surface that is fixed to the end surface of the side wall,
    The fixing surface is provided with a protruding portion that protrudes toward the end surface and that is continuous along the length direction,
    The breaker according to claim 4, wherein the protruding portion is formed outward of the inner surface of the side wall in the width direction.
  6. 　前記突出部の前記長さ方向に垂直な断面積は、前記側壁の前記長さ方向の前記中央部に向って減少している、請求項５記載のブレーカー。 The breaker according to claim 5, wherein a cross-sectional area of the protrusion perpendicular to the lengthwise direction decreases toward the central portion of the side wall in the lengthwise direction.
  7. 　請求項４乃至６のいずれかに記載のブレーカーを備えたことを特徴とする電気機器用の安全回路。 A safety circuit for electric equipment, comprising the breaker according to any one of claims 4 to 6.
  8.   請求項４乃至６のいずれかに記載のブレーカーを備えたことを特徴とする２次電池パック。  A secondary battery pack comprising the breaker according to any one of claims 4 to 6.
PCT/JP2019/041654 2018-11-08 2019-10-24 Thermally-actuated element, breaker, safety circuit, and secondary battery pack WO2020095694A1 (en)

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JP2018-210564 2018-11-08

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0315444U (en) * 1989-06-28 1991-02-15
JP2011233314A (en) * 2010-04-27 2011-11-17 Nec Schott Components Corp Temperature protection element
JP2016051594A (en) * 2014-08-29 2016-04-11 株式会社小松ライト製作所 Breaker, and safety circuit and secondary battery circuit having the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0315444U (en) * 1989-06-28 1991-02-15
JP2011233314A (en) * 2010-04-27 2011-11-17 Nec Schott Components Corp Temperature protection element
JP2016051594A (en) * 2014-08-29 2016-04-11 株式会社小松ライト製作所 Breaker, and safety circuit and secondary battery circuit having the same

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