JP6590501B2 - External PTC element and cylindrical battery - Google Patents

Description

  The present invention relates to a PTC element externally attached to a battery. The present invention also relates to a cylindrical battery to which the external PTC element is attached.

  In an electronic device that cannot be replaced by a user, the battery itself is mounted as an electronic component on the circuit board of the electronic device. An electronic device that handles a large current requires a safety device for interrupting the current when the temperature of the battery rises due to a short circuit inside or outside the battery. Thus, some batteries capable of discharging a large current, such as lithium batteries, incorporate a PTC (Positive Temperature Coefficient) element. As is well known, a PTC element usually has a low resistance, but a chip having a laminated structure in which metal foils are arranged on both sides of a plate-like polymer material (polymer) or ceramic material whose electrical resistance increases when the temperature rises. It is a part. The PTC element incorporated in the battery is usually disposed in a sealing body that also serves as one electrode terminal.

  However, some batteries have a sealing structure in which a PTC element cannot be built. Alternatively, there is a case where the current interruption characteristic of the PTC incorporated in the battery does not match the characteristic required on the electronic device side. Therefore, as an electronic component corresponding to such a case, there is a PTC element (hereinafter also referred to as an external PTC element) that is externally attached to an electrode terminal of a battery. Then, the battery to which the external PTC element is attached is incorporated in the electronic device.

  FIG. 1 shows a conventional externally attached PTC element 101, and here shows a state where it is attached to a cylindrical battery 50. In the figure, the constituent members of the external PTC element 101 are indicated by different hatchings. As shown in FIG. 1, the external PTC element 101 has a structure in which metal plates (120, 130) are laminated on the front and back of a PTC element which is a plate-like chip part (hereinafter also referred to as PTC chip part 10). The PTC chip component 10 and the metal plates (120, 130) are joined by reflow soldering. The external PTC element 101 is attached to the electrode terminal 52 on either end face of the cylindrical battery 50. In the illustrated example, one metal plate 130 constituting the external PTC element 101 and an electrode terminal (electrode terminal 52 in the drawing) on either one of both end faces of the battery 110 are fixed by spot welding or the like. Thus, the external PTC element 101 is attached to the cylindrical battery 50. When the cylindrical battery 50 to which the external PTC element 101 is attached is mounted on a circuit board or the like, the lead wire 70 is connected to the other metal plate 120 using solder 60 or the like. Further, for example, a terminal plate 80 made of only a metal plate is attached to the other electrode terminal 51 of the cylindrical battery 50, and the lead wire 70 is soldered to the terminal plate 80. Then, the cylindrical battery 50 is mounted by soldering the lead wire 70 to the circuit board. Note that the conventional external PTC element is not limited to the example shown in FIG. 1, but a PTC chip component made up of two strip-shaped metal plates (220, 230) like the external PTC element 201 shown in FIG. There is also a structure with 10 held. Also in this case, the metal plates (220, 230) and the PTC chip component 10 are joined by reflow soldering. Patent Document 1 below describes an external PTC element having a structure in which a plate-like PTC chip component is sandwiched between two strip-like metal plates. Non-Patent Document 1 below describes the structure and characteristics of a PTC element using a PTC chip part called a “polyswitch” using a polymer as a PTC material.

JP 2002-150918 A

Tyco Electronics Japan GK, ““ Polyswitch overview and selection method ”“ Polyswitch reliability ”, [online], [Search February 27, 2015], Internet <URL: http: // www. te.com/japan/bu/circuitprotection/polyswitch/pdf/2011_fundamentals.pdf>

  A conventional external PTC element has a structure in which a metal plate and a PTC chip component are joined by reflow soldering while the PTC chip component is sandwiched between two metal plates. In the conventional external PTC element, various problems occur due to this reflow soldering process. For example, before mass production of an external PTC element, it is necessary to determine detailed conditions such as the amount of reflow solder applied and the alignment accuracy to the application location. In addition, complicated steps in the reflow soldering process are required for mass production. That is, reflow soldering is applied to the top surface of the bottom plate, and PTC chip components are aligned and stacked on the bottom plate. Further, reflow solder is aligned and applied to the upper surface of the PTC chip component, and a top plate is aligned and laminated on the PTC chip component. Then, the bottom plate, the PTC chip component, and the top plate in a laminated state are bonded to each other by melting the reflow solder by heating and solidifying the molten solder by cooling.

  Thus, since the conventional external PTC element is manufactured by the reflow soldering process which requires a complicated operation | work, cost reduction is difficult. Further, in the reflow soldering process, it is necessary to align and apply the reflow solder with high accuracy. If the position is shifted, the bottom plate and the top plate may be short-circuited. That is, in order to ensure high reliability, extremely strict process management is necessary, and this strict process management also causes an increase in cost.

  Therefore, an object of the present invention is to provide an external PTC element that can be manufactured by a simple process and has high reliability, and a cylindrical battery having the external PTC element attached thereto.

The present invention for achieving the above object is an external PTC element attached to an electrode terminal of a cylindrical battery having electrode terminals on both end faces,
A plate-like PTC chip component, a top plate made of a metal plate, and a sheet-like insulator are laminated in this order above a bottom plate made of a metal plate arranged below,
The PTC chip component is disposed in a facing area between the top plate and the bottom plate,
The bottom plate is provided with tongues protruding on the left and right sides of the facing area with the top plate, with one direction orthogonal to the vertical direction as the left and right direction,
The tongue piece is caulked in the vertical direction, and the bottom plate, the PTC element, the top plate, and the insulator are pressure-bonded in the stacking direction,
The insulator has a wall surface portion that hangs downward from a lower surface edge, and the wall surface portion is interposed between a side surface of the top plate and the tongue piece,
The direction perpendicular to the up and down direction and the left and right direction is the front and back direction, and the top plate is formed in the shape of a lead terminal that can be mounted on a circuit board while the front plate extends forward with respect to the bottom plate ,
The bottom plate has a structure for preventing the top plate from deviating backward by contacting the rear end of the top plate at the rear end ,
The insulator is interposed between a rear end of the bottom plate and a rear end of the top plate ;
This is an externally attached PTC element.
Alternatively, the top plate is provided with a structure that prevents contact with the rear end or front end or both front and rear ends of the tongue piece and deviates in the front, rear, or both front and rear directions .
The insulator is interposed between the top plate and the tongue ;
An external PTC element characterized by this can also be obtained.

  The PTC chip component, the top plate, and the insulator are formed with internal cavity regions communicating in the vertical direction, and the internal cavity regions are vertically oriented so that the upper surface of the bottom plate is exposed upward. It is good also as an external PTC element characterized by having contacted by.

  A cylindrical battery to which the external PTC element according to any one of the above is attached is also within the scope of the present invention, and the cylindrical battery has electrode terminals on both upper and lower end surfaces, and an electrode on one end surface. The terminal is attached with the bottom surface of the bottom plate in contact with the terminal.

  The external PTC element of the present invention has a structure that can be manufactured by a simple process, can be provided at a lower cost, and is reliable. The cylindrical battery to which the external PTC is attached can also be provided at a lower cost, and the reliability is ensured. Other effects will be clarified in the following description.

It is a figure which shows an example of the conventional external PTC element. It is a figure which shows the other example of the conventional external PTC element. It is a figure which shows the external PTC element which concerns on 1st Example of this invention, and its structure. It is a figure which shows the structure of the external PTC element which concerns on the said 1st Example. It is a figure which shows the cylindrical battery of the state in which the external PTC element which concerns on the said 1st Example was attached. It is a figure which shows the external PTC element which concerns on 2nd Example of this invention, and its structure. It is a figure which shows the cylindrical battery of the state in which the external PTC element based on the said 2nd Example was attached. It is a figure which shows the external PTC element which concerns on 3rd Example of this invention, and its structure. It is a figure which shows the cylindrical battery of the state in which the external PTC element based on the said 3rd Example was attached. It is a figure which shows the modification of the said 3rd Example. It is a figure which shows the external PTC element which concerns on 4th Example of this invention, and its structure. It is a figure which shows the modification of the said 4th Example. It is a figure which shows the other modification of the said 4th Example.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that in the drawings used for the following description, the same or similar parts may be denoted by the same reference numerals and redundant description may be omitted. In some drawings, reference numerals may be assigned to parts that are not required in other drawings if unnecessary.

=== First Embodiment ===
As an embodiment of the present invention, an external PTC element to which a cylindrical battery is attached is given. 3 and 4 show an external PTC element 1a according to the first embodiment of the present invention. 3 and FIG. 4, each member constituting the external PTC element 1a is indicated by different hatching. First, the outline of the external PTC element 1a according to the first embodiment will be described with reference to FIG. 3A is an exploded perspective view before assembling the external PTC element 1a according to the first embodiment, and FIG. 3B is a perspective view of the external PTC element 1a after assembly. 4A is a plan view of the external PTC element 1a, and FIG. 4B is a cross-sectional view taken along the line aa in FIG. 4A. Hereinafter, the configuration and structure of the first embodiment 1a will be described in more detail with reference to FIGS.

  The external PTC element according to the first embodiment (hereinafter also referred to as the first embodiment 1a) has a basic configuration and structure common to the other embodiments, and is shown in FIG. Thus, it has a laminated structure in which the flat PTC chip component 10 is sandwiched between two metal plates (20, 30). In this example, a nickel plate is used as the metal plate (20, 30), and the PTC chip component 10 is a so-called “polyethylene” in which a conductive polymer having a characteristic that electrical resistance increases at high temperatures is sandwiched between metal foils such as aluminum foil. "Switch" is used.

Here, in each of the following embodiments including the first embodiment 1a, of the two metal plates (20, 30) sandwiching the PTC chip component 10, the metal plate directly attached to the electrode terminal of the battery 30 is referred to as a “bottom plate”. The metal plate 20 facing the bottom plate 30 via the PTC chip component 10 is also referred to as a “top plate”. Further, the bottom plate 30 is defined as a lower side, and the upper and lower directions are defined as the PTC chip component 10 and the top plate 20 are laminated in this order above the bottom plate 30. Accordingly, FIG. 4A is a plan view when the first embodiment 1a is viewed from above.
Although the first embodiment 1a has the same basic configuration as a conventional external PTC element in which the PTC chip component 10 is sandwiched between the bottom plate 30 and the top plate 20, the top plate 20 and the bottom plate 30 are reflowed with the PTC chip component 10. The difference is that they are not joined by soldering. Specifically, as shown in FIG. 3A, in the first embodiment 1a, tongue pieces 31 protruding in opposite directions are formed on two opposite edges of the rectangular bottom plate 30. The tongue piece 31 is bent upward at the base end 33 with the two edges of the base plate 30 as base ends 33. Here, assuming that two directions perpendicular to the vertical direction are the front-rear direction and the left-right direction, the tongue pieces 31 are formed on both the left and right sides of the bottom plate 30, and as shown in the figure, the left and right directions, and the front-rear direction Each direction shall be specified.

  On the upper surface 32 of the bottom plate 30, the PTC chip component 10 and the top plate 20 are laminated in this order in a region where the left and right tongue pieces 31 face each other. 4A, the PTC chip component 10 is disposed in a region where the bottom plate 30 and the top plate 20 face each other when viewed from above. In the assembled first embodiment 1a, as shown in FIGS. 3B and 4B, the tip 34 side of the tongue piece 31 is bent downward, and the tongue piece 31 is caulked in the vertical direction. It has been. Accordingly, the bottom plate 30, the PTC chip component 10, and the top plate 20 are brought into a pressure-bonded state and are joined to each other. Further, when the tongue piece 31 is caulked, if the tip 34 of the tongue piece 31 comes into direct contact with the upper surface 21 of the top plate 20, the bottom plate 30 and the top plate 20 are short-circuited. An insulator (hereinafter also referred to as an insulating sheet 40) formed from a sheet-like resin or the like is placed on the upper surface 21 of the plate 20. The tip 34 of the tongue piece 31 is crimped in a state where it abuts against the upper surface 41 of the insulating sheet 40.

  Further, as shown in detail in FIGS. 3A and 4B, the insulating sheet 40 has wall surface portions 42 suspended from the left and right edges of the lower surface periphery. It is interposed between the side surface of the plate 20 and prevents a short circuit between the tongue piece 31 formed integrally with the bottom plate 30 and the side surface of the top plate 20.

  FIG. 5 shows a state in which the first embodiment 1a is attached to the cylindrical battery 50. The illustrated cylindrical battery (hereinafter also referred to as a battery 50) is an electrode terminal 52 having one end surface formed of a flat surface. A convex electrode terminal 51 is formed on the other end face. FIG. 5 shows an example in which the first embodiment 1a is attached to the electrode terminal 52 on the flat surface side. As shown in FIG. 5, when the first embodiment 1a is attached to the battery 50, the electrode terminal is provided on the upper surface 32 of the bottom plate 30 in the region 35 exposed to the outside in the front-rear direction from the region facing the top plate 30. A portion 36 to be welded to 52 (for example, spot welding or laser welding) is provided. Alternatively, the bottom plate 30 and the electrode terminal 52 can be attached using a conductive adhesive or the like. Of course, the first embodiment 1a can also be attached to the convex electrode terminal 51. When the battery 50 to which the first embodiment 1a is attached is mounted on the circuit board, one end of the lead wire 70 may be connected to an appropriate position of the top plate 20 using the solder 60 or the like. In this example, the front and rear lengths of the top plate 20 are formed longer than the front and rear lengths of the insulating sheet 40, and the lead wires 70 are formed on the upper surface 21 of the top plate 20 in the region 22 exposed to the outside in the front and rear direction from the planar region of the insulating sheet. Soldering. For the other electrode terminal 51 of the battery 50, a terminal plate 80 made of only a metal plate is attached, and one end of the lead wire 70 is soldered to the terminal plate 80. Then, the other end of the lead wire 70 connected to the top plate 20 and the terminal plate 80 of the first embodiment 1a may be connected to the circuit board.

  As described above, the first embodiment 1a can be manufactured through a simple process in which the tongue piece 31 formed integrally with the bottom plate 30 is caulked without going through the reflow soldering process. The insulating sheet 40 is interposed between the tongue piece 31 and the upper surface 21 or the side surface of the top plate 20 to reliably prevent a short circuit between the bottom plate 30 and the top plate 20. That is, the first embodiment 1a is inexpensive and has high reliability.

=== Second Embodiment ===
As shown in FIG. 5, when attaching the first embodiment 1a to the electrode terminal 52 such as the cylindrical battery 50, welding is performed in the region 35 exposed upward in the bottom plate 30, or the bottom plate 30 and the electrode are connected. The terminal 52 (or the electrode terminal 51) is bonded using a conductive adhesive. However, considering the attachment strength, it is desirable to attach the external PTC element to the electrode terminal by welding. However, in the first embodiment 1a, the welding can be performed only in the region 35 exposed outside the planar region of the top plate 20 on the upper surface of the bottom plate 30. Therefore, the electrode terminal 52 on the side where the first embodiment 1a is attached in the battery 50 needs to be a flat surface, and the flat surface needs to have a plane area wider than the bottom plate 30. It was. For example, the general cylindrical battery 50 shown in FIG. 5 includes a convex electrode terminal 51 and an electrode terminal 52 having a flat surface. When the battery 50 is mounted on a circuit board, the convex battery terminal is convex for some reason. When it is necessary to attach an external PTC element to the electrode terminal 51 side, in the first embodiment 1a, if the region 35 for welding in the bottom plate 30 is outside the planar region of the convex electrode terminal 51, the convex shape The electrode terminal 51 cannot be attached by welding. Of course, even if it is attached to the electrode terminal 52 on the flat surface side, if it is a small-diameter battery, attachment by welding is similarly difficult. Therefore, as a second embodiment, an external PTC element that can be welded to a small-diameter battery or a convex electrode terminal is given.

  FIG. 6 shows an external PTC element according to the second embodiment (hereinafter also referred to as second embodiment 1b). 6A is an exploded perspective view before assembling the second embodiment 1b, and FIG. 6B is a perspective view showing the second embodiment 1b after assembly. As shown in FIG. 6A, in the second embodiment 1b, the flat PTC chip component 10, the top plate 20, and the insulator sheet 40 are arranged in this order on the upper surface 32 of the bottom plate 30 similar to the first embodiment. It is laminated. In addition, wall surfaces 42 are suspended from the left and right sides of the periphery of the lower surface of the insulator sheet 40. However, these components (10, 20, 40) stacked on the bottom plate 30 are formed with internal cavity regions (11, 23, 43) communicating in the vertical direction. In this example, the PTC chip component 10a, the top plate 20, and the insulator sheet 40 are all rectangular in plan shape, and a circular internal cavity region (11, 23, 43) is formed at the center thereof. In addition, the PTC chip component 10, the top plate 20, and the insulator sheet 40 have substantially the same area of the internal cavity regions (11, 23, 43).

  In the second embodiment 1b after assembly as shown in FIG. 6B, the PTC chip component 10, the top plate 20, and the insulating sheet 40 are viewed from above through the internal cavity regions (11, 23, 43). The upper surface 32 of the bottom plate 30 is exposed. And the welding location is provided in the exposed area | region 37. FIG. FIG. 7 shows a state in which the second embodiment 1b is attached to the cylindrical battery 50. Here, the example which attached 2nd Example 1b to the convex electrode terminal 51 of the cylindrical battery 50 was shown. The internal cavity region (11, 23, 43) in the second embodiment 1b is disposed immediately above the convex electrode terminal 51, and the circular shape of the bottom plate 30 exposed in the internal cavity region (11, 23, 43) is provided. A spot welding point 36 is provided in the region 37. Thus, in 2nd Example 1b, even if the area of an electrode terminal (51, 52) is small, welding becomes possible and big attachment strength can be ensured.

=== Third embodiment ===
When the battery to which the external PTC element according to the first and second embodiments is attached is mounted on a substrate or the like, a lead wire is attached to the external PTC element. Therefore, it costs the component cost related to the lead wire itself, the manufacturing cost required for the process for attaching one end of the lead wire to the external PTC element, the manufacturing cost required for the process of soldering the other end of the lead wire to the circuit board, etc. It becomes difficult to further reduce the cost of the electronic device in which the battery is incorporated. In addition, since it is necessary to route the lead wire, there is a possibility that downsizing of the electronic device may be hindered. Therefore, as a third embodiment of the present invention, an external PTC element that can easily and inexpensively mount a battery to be attached and can contribute to downsizing of an electronic device in which the battery is incorporated is exemplified.

  FIG. 8 is a diagram showing an external PTC element (hereinafter also referred to as third embodiment 1c) according to the third embodiment. FIG. 8A is a perspective view showing the shape of the top plate 20 constituting the third embodiment 1c, and FIG. 8B is a perspective view showing the appearance of the third embodiment 1c. As shown in FIG. 8 (A), in the third embodiment 1c, the top plate 20 extends in the front-rear direction, and the front end side is a lead terminal portion 24 processed into a shape that can be directly mounted on a circuit board, The top plate 20 itself functions as a lead terminal plate. In the illustrated example, the lead terminal portion 24 of the top plate 20 has a shape of a lead pin inserted into a through hole of the circuit board. In the illustrated example, a circular internal cavity region 23 is formed in the rectangular region on the rear end side so as to communicate in the vertical direction as in the second embodiment. 8B, in the third embodiment 1c, the top plate 20 is sandwiched from the left and right by the pair of tongues 31 facing in the left and right direction, and the lead terminal portion 24 is forward of the bottom plate 30. Protruding.

  FIG. 9 shows a state where the third embodiment 1c is attached to the battery 50. The third embodiment 1c is attached to one electrode terminal 52 of the battery 50 by a method such as welding. Similarly to the top plate 20, the other electrode terminal 51 is attached only to a terminal plate (hereinafter also referred to as a lead terminal plate 80) having a lead pin shape 81 on the tip side 81 by a method such as welding. The battery 50 is mounted on the circuit board by soldering the lead terminal portion 24 of the top plate 20 and the front end of the lead terminal board 80 while being inserted into the through hole of the circuit board. The shape of the lead terminal portion 24 in the top plate 20 can be changed as appropriate according to the mounting structure on the circuit board, and may not be the shape of the lead pin. For example, like the external PTC element 1d shown in FIG. 10, the top plate 20 may be provided with a lead terminal portion 24 in which a notch 25 to be inserted into the edge of the circuit board is formed.

=== Fourth embodiment ===
In the external PTC elements according to the first to third embodiments described above, the top plate is pressure-bonded from above while being sandwiched by the tongue pieces from the left and right directions together with the PTC chip components. Therefore, there is almost no possibility that the top plate deviates in the left-right direction. Since it is assumed that the external PTC element according to the first and second embodiments is attached to the battery and the battery is mounted on the circuit board, a lead wire is used. There is almost no opportunity to apply force in the front-back direction. On the other hand, in the third embodiment, lead terminal portions for mounting directly on the circuit board are formed on the top board in order to solve various problems caused by the mounting form using the lead wires. In the third embodiment, there is a need to consider the possibility that the top plate deviates in the front-rear direction due to the lead terminal portion. Specifically, referring to FIG. 9, when an excessive force is applied to the battery 50 when the battery 50 is mounted or after the battery 50 is mounted, the force is directly applied to the top plate. 20, the top plate 20 may deviate in the front-rear direction. In particular, during mounting, a backward force is often applied to the top plate 20 by pushing the lead terminal portion 24 on the front end side of the top plate 20 into a through hole of the circuit board. And when the force is excessive, the top plate 20 may deviate backward. After the battery 50 is mounted, the battery 50 itself is incorporated into the electronic device together with the circuit board, so there is little opportunity to apply a large force to the top plate 20 through the battery 50. Therefore, as a fourth embodiment of the present invention, an external PTC element having a structure for preventing the top plate 20 from deviating backward is cited.

  FIG. 11 shows an external PTC element (also referred to as fourth example 1e) according to the fourth example. FIG. 11A is an exploded perspective view showing the fourth embodiment 1e before assembly, and FIG. 11B is a perspective view showing the fourth embodiment 1e after assembly. FIG. 11C is a perspective view when the insulating sheet 40 constituting the fourth embodiment 1e is viewed from the lower front side. As shown in FIG. 11A, the bottom plate 30 has tongue pieces 38 formed on the rear side in addition to the tongue pieces 31 on both the left and right sides. 11B, the tongue piece 38 abuts against the rear end of the top plate 20 in a state where the rear tongue piece 38 is caulked. Thereby, even if the top plate 20 is strongly biased backward, the top plate 20 does not deviate backward. Further, as shown in FIG. 11 (C), the insulator sheet 40 has a wall surface 44 formed on the rear edge in addition to the wall surface 42 on the left and right edges, whereby the rear tongue piece 38 is interposed. The bottom plate 30 and the top plate 20 are prevented from being short-circuited. Note that the tongue piece 38 at the rear end of the bottom plate 30 is not necessarily caulked. If the tongue piece 38 is in contact with the rear end of the top plate 20 via the insulating sheet 40, the top plate 20 can be prevented from deviating backward.

<Modification>
In 4th Example 1e shown in FIG. 11, the structure for preventing the top plate 20 deviating back was provided. Of course, an external PTC element having a structure for preventing the top plate 20 from deviating in the front or both directions is also conceivable. FIG. 12 and FIG. 13 show an external PTC element (1f, 1g) having a structure for preventing the top plate 20 from deviating in the front and both front and rear directions as a modification of the fourth embodiment. First, FIG. 12 shows an external PTC element 1f having a structure for preventing the top plate 20 from deviating forward. FIG. 12A is a perspective view showing the top plate 20 constituting the external PTC element 1f, and FIG. 12B is a perspective view when the insulator sheet 40 is viewed from the upper front side. FIG. 12C is a perspective view when the insulator sheet 40 is viewed from above and behind. FIG. 12D is a perspective view of the external PTC element 1f provided with the top plate 20 shown in FIG. 12A and the insulator sheet 40 shown in FIGS. 12B and 12C. As shown in FIG. 12 (A), a protrusion 26 protruding left and right is formed at the rear end of the top plate 20, and as shown in FIGS. 12 (B) and 12 (C), the rear of the insulator sheet 40 is formed. A convex portion 45 protruding in the left-right direction is formed at the end. 12D, when the tongue piece 31 is caulked, the front end of the projection 26 of the top plate 20 abuts the rear end of the tongue piece 31 via the convex portion 45 of the insulating sheet 40. The top plate 20 is prevented from moving forward, and a short circuit between the protrusion 34 and the tongue piece 31 of the top plate 20 is prevented.

  FIG. 13 shows an external PTC element 1g having a structure for preventing the top plate 20 from deviating in both the front and rear directions. FIG. 13A is a perspective view showing the top plate 20, and FIG. 12B is a perspective view showing the insulator sheet 40. FIG. 13C is a perspective view of an external PTC element 1g provided with the top plate shown in FIG. 13A and the insulator sheet 40 shown in FIG. 13B. As shown in FIG. 13 (A), the top plate 20 is formed with a projection 26 protruding left and right at the rear end, and is spaced a predetermined distance forward from the projection 26 at the rear end. Similar protrusions 27 protrude left and right at the same position. As shown in FIG. 13B, the insulating sheet 40 is provided with a convex portion 46 that protrudes left and right in addition to the convex portion 45 at the rear end. Then, as shown in FIG. 13C, in a state where the tongue piece 31 is caulked, the rear end of the projection 27 on the front side of the top plate 20 passes through the convex portion 46 on the front side of the insulating sheet 40. The front end of the protrusion 26 on the rear side of the top plate 20 is in contact with the rear end of the tongue piece 31 via the convex portion 45 on the rear side of the insulating sheet 40. Thereby, the top plate 20 is prevented from deviating in both the front and rear directions, and a short circuit between the protrusions (24, 25) and the tongue piece 31 is prevented.

  In addition, in the external PTC element provided with the top plate on which the lead terminal portion is formed, the structure for preventing the top plate from deviating either in the front-rear direction or in both the front-rear directions is the same as the structure shown in FIGS. It is not limited, and the structure for preventing the top plate from moving in the front-rear direction is formed on the top plate itself or the bottom plate, and an insulating sheet may be interposed between the top plate and the bottom plate. .

1a to 1g, 101, 201 External PTC element, 10 PTC chip component,
11 PTC chip component internal cavity region, 20 Top plate, 23 Top plate internal cavity region,
24 Lead terminal part, 26, 27 Protruding part, 30 Bottom plate, 31, 38 Tongue piece,
40 insulating sheet, 42, 44 wall surface part, 43 internal cavity region of insulating sheet,
45, 46 Convex part, 50 battery, 51, 52 Battery electrode terminal, 60 Solder,
70 Lead wire, 80 Terminal board (Lead terminal board)

Claims (4)

An external PTC element attached to an electrode terminal of a cylindrical battery having electrode terminals on both end faces,
A plate-like PTC chip component, a top plate made of a metal plate, and a sheet-like insulator are laminated in this order above a bottom plate made of a metal plate arranged below,
The PTC chip component is disposed in a facing area between the top plate and the bottom plate,
The bottom plate is provided with tongues protruding on the left and right sides of the facing area with the top plate, with one direction orthogonal to the vertical direction as the left and right direction,
The tongue piece is caulked in the vertical direction, and the bottom plate, the PTC element, the top plate, and the insulator are pressure-bonded in the stacking direction,
The insulator has a wall surface portion that hangs downward from a lower surface edge, and the wall surface portion is interposed between a side surface of the top plate and the tongue piece,
The direction perpendicular to the up and down direction and the left and right direction is the front and back direction, and the top plate is formed in the shape of a lead terminal that can be mounted on a circuit board while the front plate extends forward with respect to the bottom plate ,
The bottom plate has a structure for preventing the top plate from deviating backward by contacting the rear end of the top plate at the rear end ,
The insulator is interposed between a rear end of the bottom plate and a rear end of the top plate ;
An external PTC element characterized by that. An external PTC element attached to an electrode terminal of a cylindrical battery having electrode terminals on both end faces,
A plate-like PTC chip component, a top plate made of a metal plate, and a sheet-like insulator are laminated in this order above a bottom plate made of a metal plate arranged below,
The PTC chip component is disposed in a facing area between the top plate and the bottom plate,
The bottom plate is provided with tongues protruding on the left and right sides of the facing area with the top plate, with one direction orthogonal to the vertical direction as the left and right direction,
The tongue piece is caulked in the vertical direction, and the bottom plate, the PTC element, the top plate, and the insulator are pressure-bonded in the stacking direction,
The insulator has a wall surface portion that hangs downward from a lower surface edge, and the wall surface portion is interposed between a side surface of the top plate and the tongue piece,
The direction perpendicular to the up and down direction and the left and right direction is the front and back direction, and the top plate is formed in the shape of a lead terminal that can be mounted on a circuit board while the front plate extends forward with respect to the bottom plate ,
The top plate has a structure that prevents contact with the rear end or front end or both front and rear ends of the tongue piece and deviates in the front, rear, or both front and rear directions .
The insulator is interposed between the top plate and the tongue ;
An external PTC element characterized by that. 3. The internal cavity region that communicates in the vertical direction is formed in the PTC chip component, the top plate, and the insulator according to claim 1, and each internal cavity region has an upper surface of the bottom plate facing upward. An external PTC element connected in the vertical direction so as to be exposed. A cylindrical battery comprising the external PTC element is mounted according to any one of claims 1 to 3, up and down with the provided electrode terminals on both end surfaces, one of said bottom plate to the electrode terminal of the end face A cylindrical battery characterized in that it is attached in a state in which the lower surface is in contact.

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