Protective components

Abstract

The protection element comprises a first electrode (1), a second electrode (2) having spring characteristics, and a fuse element material (3) arranged between the first electrode and the second electrode, wherein the fuse element material (3) is supported by being sandwiched between the first electrode (1) and the second electrode (2) in a bent state.

Description

Technical Field

[0001] The present invention relates to a protection element.

[0002] This application claims priority based on Japanese Patent Application No. 2018-209897 filed on November 7, 2018, and the contents are cited herein. Background Art

[0003] Conventionally, as a protection element for a circuit, a protection element (fuse device) including a fuse element is used. When a current exceeding a rated value flows, the fuse element generates heat and melts to cut off a current path.

[0004] As protection elements, for example, most commonly used are bracket-fixed fuses in which solder is sealed in a glass tube, chip fuses in which Ag electrodes are printed on the surface of a ceramic substrate, and screw-fixed or inserted protection elements in which a portion of a copper electrode is thinned and incorporated into a plastic casing.

[0005] This protection element is difficult to surface-mount by reflow soldering, and the efficiency of component mounting decreases. Therefore, surface-mount protection elements have been developed in recent years (for example, refer to Patent Documents 1 and 2).

[0006] Surface mounted protection elements are used, for example, as protection elements for overcharge and overcurrent of battery packs using lithium ion secondary batteries. Lithium ion secondary batteries are used in mobile devices such as notebook computers, mobile phones, and smart phones, and have also been used in power tools, electric bicycles, electric motorcycles, and electric vehicles in recent years. Therefore, protection elements for large currents and high voltages are required.

[0007] In high voltage protection elements, arc discharge may occur when the fuse element blows. If arc discharge occurs, the fuse element melts over a wide range, and there is a possibility that vaporized metal will scatter. In this case, there is a concern that a new current path will be formed by the scattered metal, or that the scattered metal will adhere to the terminals, surrounding electronic components, etc. Therefore, in high voltage protection elements, measures are implemented to prevent or stop arc discharge.

[0008] As a measure to prevent or stop arc discharge, it is known to fill an arc-extinguishing material around a fuse element (for example, refer to Patent Document 3).

[0009] In addition, as another method of stopping arc discharge, there is known a type of protection element in which a fuse element and a spring in a state of accumulating elastic restoring force are connected in series and joined with a low melting point metal (for example, refer to patent documents 4 to 6). In this type of protection element, when an overcurrent flows and the low melting point metal melts, the elastic restoring force of the spring promotes the separation of the spring and the fuse element, and the overcurrent can be quickly cut off.

[0010] Arc discharge depends on the electric field strength (voltage / distance), and arc discharge does not stop until the distance between the contacts becomes larger than a certain distance. Therefore, this type of protection element using a spring uses the elastic restoring force of the spring to quickly separate the spring and the fuse element to a distance where the arc discharge cannot be maintained, thereby quickly stopping the arc discharge.

[0011] Prior art literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent No. 6249600

[0014] Patent Document 2: Japanese Patent No. 6249602

[0015] Patent Document 3: Japanese Patent No. 4192266

[0016] Patent Document 4: Japanese Patent Application Laid-Open No. 6-84446

[0017] Patent Document 5: Japanese Patent Application Publication No. 2006-59568

[0018] Patent Document 6: Japanese Patent Application Publication No. 2012-234774 Summary of the invention

[0019] Problems to be solved by the invention

[0020] However, in the protection element using the above arc extinguishing material, the manufacturing process becomes complicated, and it is difficult to miniaturize the protection element. There is a concern that the heat generated by the heating element in the protection element may hinder the melting of the fuse element material.

[0021] Furthermore, in the protection element using the spring, the bonding strength between the fuse element and the spring is likely to decrease with time under the use environment, and there is a concern about long-term stability.

[0022] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a protection element which can ensure long-term stability and can effectively utilize the elastic restoring force of a spring to quickly prevent arc discharge during overcurrent interruption.

[0023] Methods for solving problems

[0024] In order to solve the above-mentioned problems, the present invention provides the following means.

[0025] (1) A protection element according to one embodiment of the present invention includes a first electrode, a second electrode having a spring characteristic, and a fuse element material disposed between the first electrode and the second electrode, wherein the fuse element material is supported by being sandwiched between the first electrode and the second electrode in a bent state.

[0026] (2) In the aspect described in (1) above, a shearing force may be applied to the fuse element material from the first electrode and the second electrode so that the fuse element material is sheared when an overcurrent flows.

[0027] (3) In the aspect described in any one of (1) or (2) above, at least one of the first electrode and the second electrode and the fuse element material may be joined by solder.

[0028] (4) In any one of the aspects (1) to (3) above, the first electrode and the second electrode may each include a claw portion at one end thereof, and the fuse element material may be sandwiched and supported by the claw portion of the first electrode and the claw portion of the second electrode.

[0029] (5) In the aspect described in (4) above, the first electrode and the second electrode may each include one or more claws, and the fuse element material may be sandwiched and supported by three or more claws of the first electrode and three or more claws of the second electrode being alternately arranged.

[0030] (6) In the aspect described in any one of (4) and (5) above, at least a portion of the claws included in the first electrode and the second electrode may have their tips bent toward the fuse element material.

[0031] (7) In the aspect described in any one of (1) to (6) above, the first electrode may have spring characteristics and be supported by being sandwiched between the first electrode in a bent state and the second electrode in a bent state.

[0032] (8) In the aspect described in any one of (1) to (7) above, the fuse element material may be composed of a laminate including a high melting point metal layer and a low melting point metal layer.

[0033] (9) In the aspect described in (8) above, the low melting point metal layer may be made of a Pb-free solder, and the high melting point metal layer may be made of Ag or Cu or an alloy containing Ag or Cu as a main component.

[0034] (10) In any one of the aspects (1) to (9) above, each of the first electrode and the second electrode may have an external terminal hole.

[0035] (11) In the aspect described in any one of (1) to (10) above, a first terminal member may be connected to the first electrode, and a second terminal member may be connected to the second electrode.

[0036] (12) In the aspect described in any one of (1) to (11) above, a heating element for heating the fuse element material and a third electrode for supplying electricity to the heating element may be further provided.

[0037] (13) In the aspect described in (12) above, one end of the heating element may be connected to the third electrode, and the other end may be connected to at least one of the fuse element material, the first electrode, and the second electrode.

[0038] (14) In the aspect described in (12) or (13) above, a third terminal member may be connected to the third electrode.

[0039] Effects of the Invention

[0040] According to the present invention, it is possible to provide a protection element which can ensure long-term stability and quickly prevent arc discharge during overcurrent interruption by effectively utilizing the elastic restoring force of a spring. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] [ Figure 1 ] Figure 1 It is a schematic plan view of an example of the protection element according to the first embodiment.

[0042] [ Figure 2 ] Figure 2 Yes Figure 1 The protection components shown along Figure 1 Schematic diagram of the cross section taken along line II-II'.

[0043] [ Figure 3 ] Figure 3 Yes Figure 1 The protection components shown along Figure 1 Schematic diagram of the cross section taken along line III-III'.

[0044] [ Figure 4 ] Figure 4 It is a schematic plan view of another example of the protection element according to the first embodiment.

[0045] [ Figure 5 ] Figure 5 It is a perspective view schematically showing an example of the structure of a fuse element material that can be used for the protection element according to the first embodiment.

[0046] [ Figure 6 ] Figure 6 It is a perspective view schematically showing another example of the structure of the fuse element material which can be used for the protection element according to the first embodiment.

[0047] [ Figure 7 ] Figure 7 It is a perspective view schematically showing another example of the structure of the fuse element material which can be used for the protection element according to the first embodiment.

[0048] [ Figure 8 ] Figure 8 It is a perspective view schematically showing another example of the structure of the fuse element material which can be used for the protection element according to the first embodiment.

[0049] [ Fig. 9 ] Fig. 9 It is a schematic plan view of an example of a protection element according to the second embodiment.

[0050] [ Fig.10 ] Fig.10 It is a schematic plan view of another example of the protection element according to the second embodiment.

[0051] [ Fig.11 ] Fig.11 It is a perspective schematic diagram of a protection element according to a third embodiment.

[0052] [ Fig.12 ] Fig.12 is from Fig.11 Observe in the direction of arrow A Fig.11 A side view of the protection element is shown.

[0053] [ Fig.13 ] Fig.13 About Fig.11 and Fig.12 The protection element shown is a three-dimensional schematic diagram after the fuse element material is cut off.

[0054] [ Fig.14 ] Fig.14 is from Fig.13 Observe in the direction of arrow A Fig.13 A side view of the protection element is shown.

[0055] [ Fig.15 ] Fig.15 It is a perspective schematic diagram of another example of the protection element according to the third embodiment.

[0056] [ Fig.16 ] Fig.16 About Fig.15 The protection element shown is a three-dimensional schematic diagram after the fuse element material is cut off.

[0057] [ Fig.17 ] Fig.17 About Fig.11 and Fig.12 The protection element shown is a schematic diagram of a state in which a portion including a fuse element material is covered with a cover, and is a three-dimensional schematic diagram of a state in which the protection element is covered with an upper cover and a lower cover.

[0058] [ Fig.18 ] Fig.18 It was removed Fig.15 A three-dimensional schematic diagram of the state of the upper cover.

[0059] [ Fig.19 ] Fig.19 It is a perspective schematic diagram of a protection element according to a fourth embodiment.

[0060] [ Fig. 20 ] Fig. 20 It is from Fig.19 Observe from the opposite side Fig.19 A three-dimensional schematic diagram of the protection element shown.

[0061] [ Fig.21 ] Fig.21 About Fig.19 and Fig. 20 The three-dimensional schematic diagram of the protection element shown in FIG. 1 after the fuse element material is cut off is similar to Fig.19 The corresponding figure.

[0062] [ Fig. 22 ] Fig. 22 About Fig.19 and Fig. 20 The three-dimensional schematic diagram of the protection element shown in FIG. 1 after the fuse element material is cut off is similar to Fig. 20 The corresponding figure.

[0063] [ Fig.23 ] Fig.23 It is a perspective schematic diagram of a protection element according to a fifth embodiment.

[0064] [ Fig.24 ] Fig.24 is from Fig.23 Observe in the direction of arrow A Fig.23 A side view of the protection element is shown.

[0065] [ Fig.25 ] Fig.25 is for Fig.23 and Fig.24 The protection components shown are Fig.23 A three-dimensional schematic diagram showing a state where the fuse element material is cut off when viewed from a corresponding direction.

[0066] [ Fig.26 ] Fig.26is for Fig.23 and Fig.24 The protection components shown are Fig.24 A side view schematically showing a state where the fuse element material is cut off when viewed from the corresponding direction.

[0067] [ Fig. 27 ] Fig. 27 It is a perspective schematic diagram of a protection element according to a sixth embodiment. DETAILED DESCRIPTION

[0068] Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings as appropriate. In the accompanying drawings used in the following description, in order to facilitate the understanding of the features, the features are sometimes enlarged for convenience, and the dimensional ratios of the components are sometimes different from the actual ones. The materials, dimensions, etc. illustrated in the following description are examples, and the present invention is not limited thereto, and can be implemented with appropriate changes within the scope of achieving the effects of the present invention.

[0069] (First Embodiment)

[0070] Figure 1 It is a schematic plan view of an example of the protection element according to the first embodiment. Figure 2 Yes Figure 1 The protection components shown along Figure 1 Schematic diagram of the cross section cut along the II-II' line in FIG. Figure 3 Yes Figure 1 The protection components shown along Figure 1 Schematic diagram of the cross section taken along line III-III'.

[0071] Figure 1 to Figure 3 The protection element 100 shown includes a first electrode 1, a second electrode 2 having spring characteristics, and a fuse element material 3 disposed between the first electrode 1 and the second electrode 2. The fuse element material 3 is supported by being sandwiched between the first electrode 1 and the second electrode 2 in a bent state.

[0072] <First Electrode>

[0073] The first electrode 1 is made of a conductive material. As the conductive material, for example, a metal (including an alloy) can be used. Specific examples of conductive materials include copper, brass, nickel, stainless steel, 42 alloy, etc. As described later, when the first electrode 1 itself also has spring characteristics like the second electrode 2, the same material as the second electrode 2 can be used.

[0074] Regarding the shape of the first electrode 1 (the shape of the portion other than the claw portion described later), Figure 1 The first electrode 1 shown is rectangular in plan view, but any shape may be used as long as the effect of the present invention is achieved. Figure 1In the example shown, the first electrode 1 is a plate-shaped member.

[0075] exist Figure 1 In the example shown, the first electrode 1 has a claw portion 1a at one end 1A thereof for stably supporting the fuse element material 3. Figure 1 In the example shown, the tip 1aA of the claw 1a of the first electrode 1 has a bent portion 1aAa bent toward the fuse element 3 to more stably support the fuse element 3. That is, the bent portion 1aAa has a function of preventing the fuse element 3 from falling off.

[0076] exist Figure 1 In the example shown, the first electrode 1 has one claw, but the number of claws may be two or more. When a plurality of claws are provided, the claws may be the same or different from each other. The position of the claw 1a at one end 1A may be arbitrarily selected as long as it can provide stable support.

[0077] Figure 4 It is a schematic plan view of another example of the protection element according to the first embodiment. Figure 4 In the protection element 200 shown in FIG. 1 , the first electrode 21 has two claws ( 21 a , 21 b ). Figure 4 In the figure, the reference numerals and Figure 1 The same components are regarded as the same components and the description thereof is omitted.

[0078] The thickness of the first electrode 1 is not limited, but can be set to 0.05 to 0.5 mm as a rough guide.

[0079] <Second Electrode>

[0080] The second electrode 2 is made of a conductive material having spring characteristics. As the conductive material having spring characteristics, metals (including alloys) can be exemplified. Among them, metal materials (including alloys) having low resistance and suitable for leaf spring materials are preferred, and specific materials include phosphor bronze, copper alloy, titanium copper, Corson alloy, beryllium copper, etc.

[0081] Here, in this specification, "spring characteristics" refers to the property of deforming when a force is applied and restoring when the force is removed. Specifically, it means that the electrode supporting the fuse element material 3 in a bent state returns to the position before the bending after the fuse element material 3 is cut due to an overcurrent. That is, in the protection element 100 of the present embodiment, the fuse element material 3 is supported in a manner such that the electrode is bent within the range in which it can be elastically deformed. The electrode may be in a bent state as a whole or as a part of it. In the case where the fuse element material 3 is supported in a state in which a part of the electrode is bent (for example, Figure 1In the case of , it is the part of the electrode that is deflected that takes on the spring characteristics.

[0082] Regarding the shape of the second electrode 2, Figure 1 The second electrode 2 shown is rectangular in plan view, but any shape may be used as long as the effect of the present invention is achieved. Figure 1 In the example shown, the second electrode 2 is a plate-shaped member.

[0083] exist Figure 1 In the example shown, the second electrode 2 has claws 2a and 2b at one end 2A for supporting the fuse element material 3. Figure 1 In the example shown, the tip 2aA of the claw 2a of the second electrode 2 has a bent portion 2aAa bent toward the fuse element 3 in order to more stably support the fuse element 3. The tip 2bA of the claw 2b also has a bent portion 2bAa. Figure 1 In the example shown, the second electrode 2 includes two claws 2 a and 2 b , but the number of claws may be one or three or more.

[0084] In such Figure 1 When a plurality of claws 2a and 2b are provided as in the example shown, these claws may be the same or different from each other. Figure 1 As shown in the example, since the fuse element material 3 is supported in a state where the claws 2a and 2b of the second electrode 2 are bent, the structure (width, thickness, shape, etc.) of the claws 2a and 2b has a great influence on the cutting or shearing of the fuse element material 3.

[0085] Here, in this specification, "shearing" refers to the action of shearing the fuse element material. In addition, the "shearing force" described later means that if a pair of forces in opposite directions act in parallel to a certain cross section of the fuse element material 3, the fuse element material 3 is subjected to an action such that it slides and breaks along the surface, and the "shearing force" is a force that imparts such an action. A pair of forces in opposite directions are applied to the fuse element material 3 from the claw 1a of the first electrode 1 and the claws 2a, 2b of the second electrode 2, respectively.

[0086] The thickness of the second electrode 2 is not limited, but can be set to 0.05 to 0.5 mm as a rough guide.

[0087] The thickness of the second electrode 2 may be the same as the entire thickness, or may have different thicknesses in parts. For example, by forming the second electrode 2 so that only the part (in the middle of the second electrode 2) that sandwiches and supports the fuse element material 3 is Figure 1In the example, the claws 2a, 2b) are thinned, and other parts are not thinned, so that the rigidity as a connection terminal to the outside can be maintained and the spring characteristics of the material of the sandwiched fuse element can be improved.

[0088] As a method of thinning a part of the second electrode 2 , for example, a known metal processing method such as rolling can be used.

[0089] <Fuse Element Materials>

[0090] As the fuse element material 3, a material used in a known fuse element can be used. The fuse element material 3 is a component that does not substantially deform (within the range that achieves the effect of the present invention) even when a force is applied to the device having the protection element at the temperature caused by the power supply during normal operation. This is because, if not, the fuse element material 3 deforms over time and cannot function as a fuse element material. Therefore, the fuse element material 3 is not a thin sheet that deforms when a force is applied, but a block material (plate, rod, square material, etc.) that does not deform even when a force is applied.

[0091] The fuse element material 3 is sandwiched and supported by the first electrode 1 and the second electrode 2 in a bent state. Figure 1 to Figure 3 In the example shown, the fuse element material 3 is supported in a state of being sandwiched between the claw portion 1a of the first electrode 1 and the claw portions 2a and 2b of the second electrode 2 in a bent state. Figure 1 That is, it is preferable to arrange the claws 2a, the claws 1a, and the claws 2b in this order so that they do not overlap when viewed from above.

[0092] The size of the fuse element material 3 (based on shape, thickness, width, length, etc.) can be any size that can be cut by the first electrode 1 and the second electrode 2 in a bent state due to the flow of overcurrent, as long as it is not deformed by the power supply during normal operation (within the range of achieving the effect of the present invention).

[0093] In the protection element 100, the claws 2a and 2b of the second electrode 2 having spring characteristics are bent, and the fuse element material 3 is sandwiched from above and below together with the claw 1a of the first electrode 1 to support it. The second electrode 2 is bent so as to return to the claw 1a side of the first electrode 1. Therefore, a force is applied to the fuse element material 3 from the claws 2a and 2b of the second electrode 2 toward the claw 1a of the first electrode 1, and a force is applied from the first electrode 1 toward the second electrode 2. That is, forces are applied to the fuse element material 3 from the first electrode 1 and the second electrode 2 in opposite directions.

[0094] In this state, an overcurrent flows through the device having the protection element 100, and the temperature of the fuse element material 3 becomes higher than the temperature caused by the energization in normal operation. As a result, when the fuse element material 3 softens or semi-melts, the fuse element material 3 is cut or sheared by the force applied from the claw 1a of the first electrode 1 and the claws 2a and 2b of the second electrode 2, and the circuit current is cut off. In this way, in the protection element 100, the fuse element material 3 itself is physically cut off, which is different from the above-mentioned spring-utilizing type protection element that cuts off the connection between the fuse element and the spring. In the case where the fuse element material 3 is cut off not only in the case where it is not melted but only softened, but also in the case where it is cut off in the state where part of it is not melted, it is considered that in most cases it can be said that it is sheared based on the above-mentioned shearing force, but the fuse element material 3 can also be cut in a way that cannot be said to be sheared based on the shearing force.

[0095] In addition, arc discharge depends on the electric field strength which is inversely proportional to the distance, so the distance between the cut surfaces of the cut fuse element material 3 needs to be increased. In the protection element 100, the distance between the cut surface of the fuse element material 3 cut by the claw 1a of the first electrode 1 and the cut surface of the fuse element material 3 cut by the claws 2a and 2b of the second electrode 2 increases rapidly due to the elastic restoring force (force restoring by spring characteristics) of the claws 2a and 2b of the second electrode 2. Therefore, arc discharge can be stopped quickly.

[0096] Furthermore, in the protection element 100 , the fuse element material 3 can be cut at a softening temperature before the fuse element material 3 becomes molten (ie, a temperature lower than the temperature at which the fuse element material 3 becomes molten), thereby reducing the risk of arc discharge.

[0097] The fuse element material 3 may also be composed of a laminate including a high melting point metal layer and a low melting point metal layer. In this case, the rigidity of the fuse element material 3 is maintained by the high melting point metal layer, and the low melting point metal layer softens the fuse element material 3 at a lower temperature or makes it semi-molten, so that the fuse element material can be cut.

[0098] As the low melting point metal used in the low melting point metal layer, a solder such as a Pb-free solder mainly composed of Sn is preferably used. This is because the melting point of Sn is 217° C., and therefore the solder mainly composed of Sn has a low melting point and becomes soft at low temperatures.

[0099] As the high melting point metal used for the high melting point metal layer, Ag, Cu or alloys thereof as main components are preferably used. This is because, for example, the melting point of Ag is 962°C, and therefore the high melting point metal layer composed of an alloy with Ag as main component can maintain rigidity at a temperature at which the low melting point metal layer softens.

[0100] As the structure of the laminated body, various structures can be adopted. Figures 5 to 8 A perspective view schematically showing an example of the structure of a laminate is shown.

[0101] Figure 5 The laminate (fuse element material) 3A shown is in a square or plate shape, with a low melting point metal layer 3Aa as the inner layer and a high melting point metal layer 3Ab as the outer layer. Alternatively, the low melting point metal layer 3Aa may be the outer layer and the high melting point metal layer 3Ab may be the inner layer.

[0102] Figure 6 The laminate (fuse element material) 3B shown is in the shape of a round rod, with a low melting point metal layer 3Ba as the inner layer and a high melting point metal layer 3Bb as the outer layer. Alternatively, the low melting point metal layer 3Ba may be the outer layer and the high melting point metal layer 3Bb may be the inner layer.

[0103] Figure 7 The laminated body (fuse element material) 3C shown is a rectangular or plate-shaped laminated body, and is a laminated body of a two-layer structure in which a low melting point metal layer 3Ca and a high melting point metal layer 3Cb are laminated.

[0104] Figure 8 The stacked body (fuse element material) 3D shown is a square or plate-shaped stacked body, and is a three-layered stacked body formed by sandwiching a low melting point metal layer 3Da with a high melting point metal layer 3Db and a high melting point metal layer 3Dc. Conversely, it can also be set to a three-layer structure formed by sandwiching a high melting point metal layer with two low melting point metal layers.

[0105] Figures 5 to 8 The laminated bodies (fuse element materials) 3A to 3D shown are two-layer or three-layer laminated bodies, but the number of laminated low melting point metal layers and high melting point metal layers is not particularly limited. The fuse element material may also be a laminated body of four or more layers.

[0106] At least one of the first electrode 1 and the second electrode 2 is preferably joined to the fuse element material 3 by solder, and more preferably both the first electrode 1 and the second electrode 2 are joined to the fuse element material 3 by solder. This is to reduce the resistance between the first electrode 1 or the second electrode 2 and the fuse element material 3. As the material of the solder, a known material can be used, but from the viewpoint of resistivity and melting point, a material containing Sn as a main component is preferred.

[0107] (Second Embodiment)

[0108] Fig. 91 is a schematic plan view of a protection element according to the second embodiment. Components using the same reference numerals as those in the first embodiment have the same structure and description thereof is omitted. In addition, description of components having the same functions as those in the first embodiment may be omitted even if reference numerals are different.

[0109] The main difference between the protection element involved in the second embodiment and the protection element involved in the first embodiment is that the first electrode and the second electrode have external terminal holes. That is, the protection element involved in the first embodiment is used by separately installing external terminals, but the protection element involved in the second embodiment is a structure in which the first electrode and the second electrode are integrally formed with the external terminals.

[0110] Specifically, Fig. 9 The protection element 400 shown includes a first electrode 41, a second electrode 42 having spring characteristics, and a fuse element material 3 arranged between the first electrode 41 and the second electrode 42. The fuse element material 3 is supported by being sandwiched between the first electrode 41 and the second electrode 42 in a bent state. The first electrode 41 and the second electrode 42 respectively include external terminal holes 45 and 46.

[0111] <External terminal hole>

[0112] The external terminal holes 45 and 46 are provided by the first electrode 41 and the second electrode 42, respectively. One of the pair of external terminal holes 45 and 46 can be used for connection to the power supply side, and the other external terminal hole can be used for connection to the load side. Here, the shape of the external terminal holes 45 and 46 is not particularly limited as long as it can be engaged with the terminal of the power supply side or the load side (not shown). Fig. 9 The external terminal holes 45 and 46 shown in the figure are through holes without an open portion, but they may also be, for example, Fig.10 As shown, a nail shape having an open portion in part.

[0113] The first electrode 41 can be made of the same material as the first electrode 1 of the first embodiment. Also, the second electrode 42 can be made of the same material as the second electrode 2 of the first embodiment.

[0114] Fig.10 FIG. 1 is a schematic plan view of a modified example of the protection element according to the second embodiment. Fig.10 In the modified example shown, the shape of the external terminal hole is Fig. 9 The examples shown are different. Fig. 9 The same components of the protection element 400 are denoted by the same reference numerals and their description is omitted.

[0115] Specifically, Fig.10The protection element 400A shown includes a first electrode 41AA, a second electrode 42AA having spring characteristics, and a fuse element material 3 arranged between the first electrode 41AA and the second electrode 42AA. The fuse element material 3 is sandwiched and supported by the first electrode 41AA and the second electrode 42AA in a bent state. The first electrode 41AA and the second electrode 42AA respectively include external terminal holes 45A and 46A having open portions 45Aa and 46A in a portion.

[0116] The position of the opening of the external terminal hole can be appropriately selected. Fig.10 In the protection element 400A shown, the openings 45Aa and 46Aa of the external terminal holes 45A and 46A are located on the opposite side of the first electrode 41AA and the second electrode 42AA to the side connected to the fuse element material 3 , but may be located at other positions.

[0117] (Third Embodiment)

[0118] Fig.11 and Fig.12 is a schematic diagram of a protection element according to a third embodiment. Fig.11 It is a three-dimensional schematic diagram. Fig.12 is from Fig.11 Schematic side view of the embodiment as viewed in the direction of arrow A. Components with the same reference numerals as those in the above embodiment have the same structure and their description is omitted. In addition, even if the reference numerals are different from those in the above embodiment but the functions are the same, the description is sometimes omitted. Fig.12 In FIG. 1 , the dotted line SS indicates a plane (SS plane) obtained by connecting the center planes in the thickness direction of the portions 51B and 52B of the first electrode 51 and the second electrode 52 excluding the claws (portions that remain substantially unchanged even after the fuse element material 3 is cut).

[0119] The protection element according to the third embodiment is mainly different from the protection element according to the above-mentioned embodiment in that the first electrode has spring characteristics in addition to the second electrode.

[0120] Specifically, Fig.11 and Fig.12 The protection element 500 shown in the figure includes a first electrode 51 having spring characteristics, a second electrode 52 having spring characteristics, and a fuse element material 3 disposed between the first electrode 51 and the second electrode 52. The fuse element material 3 is sandwiched and supported by the first electrode 51 in a bent state and the second electrode 52 in a bent state. In addition, the first electrode 51 and the second electrode 52 have external terminal holes 55 and 56, respectively.

[0121] <First Electrode>

[0122] Since the first electrode 51 has spring characteristics, the same material as the second electrode 2 of the first embodiment can be used. The first electrode 51 has a claw portion 51a at one end 51A thereof for stably supporting the fuse element material 3. In addition, the front end 51aA of the claw portion 51a of the first electrode 51 has a bent portion 51aAa bent toward the fuse element material 3 in order to more stably support the fuse element material 3. The external terminal hole 55 of the first electrode 51 can be set to the same structure as the external terminal hole 45 of the first electrode 41 of the second embodiment and the external terminal hole 45A of the first electrode 41AA. Fig.11 In the protection element 500 shown, the first electrode 51 has an external terminal hole 55 , but may not have the external terminal hole.

[0123] The thickness of the first electrode 51 may be the same as the entire thickness, or may have different thicknesses in parts. For example, by setting the first electrode 51 to have only a portion (in the middle of the first electrode 51) sandwiching the fuse element material and supporting it, Fig.11 In the example, the claw portion 51a) is thinned, and other parts are not thinned, so that the rigidity as a connection terminal to the outside can be maintained and the spring characteristics of sandwiching the fuse element material 3 can be improved.

[0124] As a part of the first electrode 51 (in Fig.11 In the example, the claw portion 51a is thinned, and a known metal processing method such as rolling can be used.

[0125] <Second Electrode>

[0126] The second electrode 52 can be made of the same material as the second electrode 2 of the first embodiment. The second electrode 52 has claws 52a and 52b at one end 52A thereof for stably supporting the fuse element material 3. In addition, in order to be able to more stably support the fuse element material 3, the front end 52aA of the claw 52a and the front end (not shown) of the claw 52b of the second electrode 52 respectively include a bending portion 52aAa and a bending portion (not shown) bent toward the fuse element material 3. The external terminal hole 56 of the second electrode 52 can be set to the same structure as the external terminal hole 46 of the second electrode 42 of the second embodiment and the external terminal hole 46A of the second electrode 42AA. In Fig.11 and Fig.12 In the protection element 500 shown, the second electrode 52 has an external terminal hole 56 , but may not have the external terminal hole.

[0127] Fig.13 and Fig.14 Show about Fig.11 and Fig.12FIG. 5 is a schematic diagram of the protection element 500 after the fuse element material is cut off. Fig.13 It is a three-dimensional schematic diagram. Fig.14 is from Fig.13 A schematic side view viewed in the direction of arrow A as shown. Fig.14 The direction indicated by the symbol x is parallel to the SS plane, and is the direction connecting the parts 51B and 52B of the first electrode 51 and the second electrode 52 except for the claws. On the other hand, the direction indicated by the symbol z is parallel to the thickness direction of the first electrode 51 or the second electrode 52. Fig.13 and Fig.14 The reference numeral 3' indicates that the fuse element material 3 is divided due to being cut.

[0128] like Figure 11 to Figure 14 As shown, the claw portion 51a, which is the bent portion (in other words, the portion having spring characteristics) of the first electrode 51, is located above the SS surface in the z direction before the fuse element material 3 is cut (see FIG. Fig.12 ), but after the fuse element material 3 is cut, it is located at a position lower than the SS surface (refer to Fig.14 ). In other words, the claw 51a of the first electrode 51 is located below the SS surface when there is no force to bend it, so that it bends in a manner that presses the fuse element material 3 from above. As for the claw 51a of the first electrode 51, the force to bend it disappears due to the cutting of the fuse element material 3, and it returns to its original state due to the elastic restoring force. That is, the claw 51a of the first electrode 51 is Fig.13 and Fig.14 The state shown in is a state where no external force acts.

[0129] Similarly, the claws 52a and 52b, which are the bent portions (in other words, the portions that have spring characteristics) of the second electrode 52, are located below the SS surface in the z direction before the fuse element material 3 is cut (see FIG. Fig.12 ), but after the fuse element material 3 is cut, it is located above the SS surface (refer to Fig.14 ). In other words, the claws 52a and 52b of the second electrode 52 are located above the SS surface in the absence of a force to bend them, so that they bend in a manner that presses the fuse element material 3 from below. As for the claws 52a and 52b of the second electrode 52, the bending force disappears due to the cutting of the fuse element material 3, and they return to their original state by elastic restoring force. That is, the second electrode 52 (the portion 52B of the second electrode 52 other than the claws and the claws 52a and 52b) is Fig.13 and Fig.14 The state shown in is a state where no external force acts.

[0130] Figure 11 to Figure 14 The bending manner of the first electrode 51 and the second electrode 52 (the positions of the claws 51a and the claws 52a and 52b before and after the fuse element material 3 is cut) is just an example and can be arbitrarily set as long as the effect of the present invention is achieved.

[0131] Fig.15 and Fig.16 A schematic diagram showing a protection element in which a first electrode having a spring characteristic is provided with two claws. Fig.15 It is a three-dimensional schematic diagram. Fig.16 3D schematic diagram after the cutoff caused by overcurrent. The components with the same reference numerals as those in the above embodiment have the same structure and the description thereof is omitted. In addition, the description of the components with the same functions as those in the above embodiment may be omitted even if the reference numerals are different.

[0132] Specifically, Fig.15 The protection element 600 shown in the figure includes a first electrode 61 having spring characteristics, a second electrode 52 having spring characteristics, and a fuse element material 3 disposed between the first electrode 61 and the second electrode 52. The fuse element material 3 is supported by being sandwiched between the first electrode 61 in a bent state and the second electrode 52 in a bent state. The first electrode 61 includes two claws (61a, 61b) at one end thereof for stably supporting the fuse element material 3. In addition, the first electrode 61 includes an external terminal hole 65.

[0133] like Fig.15 and Fig.16 As shown, the claws 61a and 61b, which are the bent portions (portions that bear spring characteristics) of the first electrode 61, are located above the portion 61B of the first electrode 61 other than the claws in the thickness direction before the fuse element material 3 is cut (see FIG. Fig.15 ), but after the fuse element material 3 is cut, it is located at a position lower than the portion 61B (refer to Fig.16 ). In other words, the claws 61a and 61b of the first electrode 61 are located below the portion 61B in the absence of a force to bend them, so that they bend in a manner that presses the fuse element material 3 from above. As for the claws 61a and 61b of the first electrode 61, the force to bend them disappears due to the cutting of the fuse element material 3, and they return to their original state. That is, the claws 51a and 51b of the first electrode 51 are Fig.16 The state shown in is a state where no external force acts.

[0134] Similarly, the claws 52a and 52b, which are the bent portions (portions that have spring characteristics) of the second electrode 52, are located below the portion 52B of the second electrode 52 other than the claws in the z direction before the fuse element material 3 is cut (see FIG. Fig.15 ), but after the fuse element material 3 is cut, it is located at a position higher than the portion 52B (refer to Fig.16 ). In other words, the claws 52a and 52b of the second electrode 52 are located above the portion 52B when there is no force to bend them, so that they bend in a manner that pushes the fuse element material 3 upward from below. As for the claws 52a and 52b of the second electrode 52, the bending force disappears due to the cutting of the fuse element material 3, and the claws 52a and 52b return to their original state. That is, the second electrode 52 (the portion 52B of the second electrode 52 other than the claws and the claws 52a and 52b) is Fig.16 The state shown in is a state where no external force acts.

[0135] Fig.17 and Fig.18 About Fig.11 and Fig.12 The protection element 500 shown is a schematic diagram of a method of covering the portion containing the fuse element material 3 with a cover 8, Fig.17 This is a three-dimensional schematic diagram of the state covered by the upper cover 8A and the lower cover 8B. Fig.18 It is a perspective view schematically showing a state where the upper cover 8A is removed.

[0136] As the cover 8 (the upper cover 8A and the lower cover 8B), a cover made of, for example, insulating resin or the like can be used.

[0137] The cover 8 (the upper cover 8A and the lower cover 8B) can also be used for the protection element according to other embodiments.

[0138] (Fourth Embodiment)

[0139] Fig.19 and Fig. 20 is a schematic diagram of a protection element according to a fourth embodiment, Fig.19 It is a three-dimensional schematic diagram. Fig. 20 It is from Fig.19 A three-dimensional schematic diagram observed from the opposite side. The components using the same reference numerals as those in the above-mentioned embodiment have the same structure and the description thereof is omitted. In addition, the description of the components having the same functions as those in the above-mentioned embodiment may be omitted even if the reference numerals are different.

[0140] The protection element according to the fourth embodiment mainly differs from the protection elements according to the above embodiments in that it further includes a heating element for heating the fuse element material and a third electrode for energizing the heating element.

[0141] Fig.19 and Fig. 20 The protection element 700 according to the fourth embodiment shown is Fig.15 The protection element 600 shown in the figure further includes a heating element for heating the fuse element material and a third electrode for energizing the heating element. Specifically, the protection element 700 includes a first electrode 61 having spring characteristics, a second electrode 52 having spring characteristics, and a fuse element material 3 arranged between the first electrode 61 and the second electrode 52, the fuse element material 3 is supported by being sandwiched between the first electrode 61 in a bent state and the second electrode 52 in a bent state, and further includes a heating element 70 for heating the fuse element material 3 and a third electrode 80 for energizing the heating element 70. In addition, in the protection element 700, the first electrode 61, the second electrode 52, and the third electrode 80 have external terminal holes 65, 56, and 81, respectively.

[0142] exist Fig.19 and Fig. 20 In the protection element 700 shown, the heat generating element 70 and the third electrode 80 are connected via a conductive connecting portion 90. In addition, the third electrode 80 is separated from the first electrode 61 and the second electrode 52 and is not connected.

[0143] exist Fig.19 and Fig. 20 In the protection element 700 shown, the heating element 70 is connected to the first electrode 61. More specifically, the heating element 70 is connected to the claws 61a and 61b of the first electrode 61. The heating element 70 may be bonded to either the second electrode 52 or the fuse element material 3.

[0144] The heating element 70 is a conductive member having a relatively high resistance value and generating heat when electricity is supplied thereto, and may be made of, for example, W, Mo, Ru, or the like.

[0145] The third electrode 80 is made of a conductive material, and the same material as that of the first electrode 1 described above can be used.

[0146] exist Fig.19 and Fig. 20 In the protection element 700 shown, since the heat generating element 70 and the third electrode 80 are provided, and the third electrode 80 is connected to the first electrode 61, the current is passed between the third electrode 80 and the first electrode 61 to generate heat in the heat generating element 70, and the fuse element material 3 can be heated. Thus, the fuse element material 3 can be cut off.

[0147] Fig.21 and Fig. 22 Show about Fig.19 and Fig. 20 The protection element 700 is shown as a three-dimensional schematic diagram after the fuse element material is cut off. Fig.21 and Fig. 22 Corresponding to Fig.19 and Fig. 20 .

[0148] like Fig.21 and Fig. 22 As shown, the claws 61a and 61b, which are the bent portions of the first electrode 61, are located above the portion 61B of the first electrode 61 other than the claws in the thickness direction before the fuse element material 3 is cut (see FIG. Fig. 20 ), but after the fuse element material 3 is cut, it is located at a position lower than the portion 61B (refer to Fig. 22 In other words, the claws 61a and 61b of the first electrode 61 are located at a lower side than 61B in the absence of a force to bend them, so that they bend in a manner that presses the fuse element material 3 from above, but the bending force disappears due to the cutting of the fuse element material 3, and the fuse element material 3 returns to its original state.

[0149] Similarly, the claws 52a and 52b, which are the bent portions of the second electrode 52, are located below the portion 52B of the second electrode 52 other than the claws before the fuse element material 3 is cut in the thickness direction (see FIG. Fig. 20 ), but after the fuse element material 3 is cut, it is located above the portion 52B of the second electrode 52 other than the claw portion (refer to Fig. 22 In other words, the claws 52a and 52b of the second electrode 52 are located above the portion 52B of the second electrode 52 other than the claws when there is no force to bend them, so that the second electrode 52 bends in a manner of pushing the fuse element material 3 upward from below, but the bending force disappears due to the cutting of the fuse element material 3, and the fuse element material 3 returns to its original state.

[0150] Before the fuse element material 3 is cut, the lower surface of the heating element 70 is in contact with the claws 61a and 61b of the first electrode 61, but after the fuse element material 3 is cut, the lower surface of the heating element 70 is in contact with the claws 52a and 52b of the second electrode 52. Furthermore, the connecting portion 90 is separated from the third electrode 80, and the power supply to the heating element 70 is interrupted, thereby stopping the heating of the heating element 70.

[0151] (Fifth Embodiment)

[0152] Fig.23 and Fig.24 is a schematic diagram of a protection element according to a fifth embodiment, Fig.23 It is a three-dimensional schematic diagram. Fig.24 is from Fig.231 is a side view of the embodiment as viewed in the direction of arrow A. Components with the same reference numerals as those in the above embodiment have the same structure and description thereof is omitted. In addition, description of components with the same functions as those in the above embodiment may be omitted even if reference numerals are different.

[0153] The main difference between the protection element involved in the fifth embodiment and the protection element involved in the above embodiment is that the first terminal component is connected in a manner overlapping in the thickness direction of the first electrode, and the second terminal component is connected in a manner overlapping in the thickness direction of the second electrode. The first terminal component and the second terminal component respectively strengthen the rigidity of the first electrode and the second electrode for connecting to the outside, thereby reducing the resistance.

[0154] Fig.23 The protection element 800 shown is relative to Fig.15 The protection element 600 shown is an example in which a first terminal member 5 is connected to a first electrode 61, and a second terminal member 6 is connected to a second electrode 52. The first terminal member 5 has an external terminal hole at a position corresponding to the external terminal hole 65 provided in the first electrode 61. In addition, the second terminal member 6 has an external terminal hole at a position corresponding to the external terminal hole 56 provided in the second electrode 52.

[0155] <First Terminal Member, Second Terminal Member>

[0156] As the material of the first terminal member 5 and the second terminal member 6, for example, copper, brass, etc. can be cited. Among them, brass is preferred from the viewpoint of enhancing rigidity. Among them, copper is preferred from the viewpoint of reducing resistance. The materials of the first terminal member 5 and the second terminal member 6 may be the same or different.

[0157] As a method of connecting the first terminal member 5 and the second terminal member 6 to the first electrode 61 and the second electrode 52 , a known method can be used, for example, welding, rivet joining, screw joining or other mechanical joining.

[0158] The thickness of the first terminal member 5 and the second terminal member 6 is not limited, but can be set to 0.3 to 1.0 mm as a rough guide. The thickness of the first terminal member 5 and the second terminal member 6 may be the same or different.

[0159] exist Fig.23 and Fig.24In the protection element 800 shown, the first terminal member 5 and the second terminal member 6 are respectively provided in a manner of covering the entire surface of the portion 61B of the first electrode 61 other than the claws 61a and 61b and the portion 52B of the second electrode 52 other than the claws 52a and 52b, but the range and shape of the coverage can be set arbitrarily as long as at least one of the effects of enhancing rigidity or reducing resistance is achieved. In addition, the portion 61B of the first electrode 61 other than the claws 61a and 61b and the portion 52B of the second electrode 52 other than the claws 52a and 52b do not need to cover the positions of the respective external terminal holes 65 and 56, and can be connected in a manner of overlapping with a portion of the first terminal member 5 and the second terminal member 6.

[0160] exist Fig.25 and Fig.26 Shown in Fig.23 and Fig.24 FIG. 8 is a schematic diagram of the protection element 800 after the fuse element material is cut off. Fig.25 It is a three-dimensional schematic diagram. Fig.26 is from Fig.25 1 is a side view of the embodiment as viewed in the direction of arrow A. Components with the same reference numerals as those in the above embodiment have the same structure and description thereof is omitted. In addition, description of components with the same functions as those in the above embodiment may be omitted even if reference numerals are different.

[0161] In the protection element 800 involved in the fifth embodiment, the first electrode 61 and the second electrode 52 are respectively provided with the first terminal member 5 and the second terminal member 6, thereby the rigidity is enhanced, so that the overall thickness of the first electrode 61 and the second electrode 52 can be thinned, and the spring characteristics can be easily adjusted. That is, the adjustment range of the thickness of the first electrode 61 and the second electrode 52 is widened. In addition, with respect to the first electrode 61 or the second electrode 52, in the structure in which only the portion supported by sandwiching the fuse element material as described above is thinned, by providing the first terminal member 5 and the second terminal member 6, the portion can be further thinned.

[0162] (Sixth Embodiment)

[0163] Fig. 27 1 is a perspective view of a protective element according to the sixth embodiment. Components with the same reference numerals as those in the above embodiment have the same structure and description thereof is omitted. In addition, description of components with the same functions as those in the above embodiment may be omitted even if the reference numerals are different.

[0164] The main difference between the protection element involved in the sixth embodiment and the protection element involved in the fifth embodiment is that it further includes a heating element for heating the fuse element material, a third electrode for energizing the heating element, and a connecting portion connecting the heating element and the third electrode, and the third electrode is also connected to a third terminal component in an overlapping manner in the thickness direction thereof. The third terminal component, like the first terminal component and the second terminal component, enhances the rigidity of the third electrode for connecting to the outside and reduces the resistance.

[0165] Fig. 27 The protection element 900 is shown relative to Fig.19 The protection element 700 shown in the figure is an example in which the first terminal member 5 is connected to the first electrode 61, the second terminal member 6 is connected to the second electrode 52, and the third terminal member 7 is further connected to the third electrode 80. The first terminal member 5 has an external terminal hole at a position corresponding to the external terminal hole 65 provided in the first electrode 61. In addition, the second terminal member 6 has an external terminal hole at a position corresponding to the external terminal hole 56 provided in the second electrode 52. In addition, the third terminal member 7 has an external terminal hole at a position corresponding to the external terminal hole 81 provided in the third electrode 80. In addition, the portion 61B of the first electrode 61 other than the claw portion and the portion 52B of the second electrode other than the claw portion do not need to cover the positions of the respective external terminal holes 56 and 65, and can be connected in a manner overlapping with a portion of the first terminal member 5 and the second terminal member 6. Furthermore, the third electrode 80 can also be abolished, and the connecting portion 90 can be directly connected to the third terminal member 7.

[0166] <Third Terminal Member>

[0167] When the materials of the first terminal member 5 and the second terminal member 6 are different, the material of the third terminal member 7 may be the same as or different from either one. In addition, the material of the third terminal member 7, the material of the first terminal member 5 and the material of the second terminal member 6 may also be the same.

[0168] As a method of connecting the third terminal member 7 and the third electrode 80 , the same method as the method of connecting the first terminal member 5 or the second terminal member 6 and the first electrode 61 or the second electrode 52 can be used.

[0169] The thickness of the third terminal member 7 may be the same as the thickness of the first terminal member 5 or the second terminal member 6, and may be the same as or different from one of them. The thickness of the third terminal member 7, the thickness of the first terminal member 5, and the thickness of the second terminal member 6 may also be all the same.

[0170] Explanation of symbols

[0171] 1, 21, 41, 41AA, 51, 61: first electrode,

[0172] 1a, 21a, 21b, 41a, 51a, 61a, 61b: claws,

[0173] 2, 42, 42AA, 52: second electrode,

[0174] 2a, 2b, 42a, 42b, 52a, 52b: claws,

[0175] 3: Fuse element material,

[0176] 5: first terminal part,

[0177] 6: second terminal part,

[0178] 7: The third terminal part,

[0179] 8: hood,

[0180] 45, 45A, 46, 46A, 55, 56: External terminal holes,

[0181] 100, 200, 400, 400A, 500, 600, 700, 800, 900: protection elements.

Claims

1. A protection element comprising a first electrode, a second electrode having spring characteristics, and a fuse element material arranged between the first electrode and the second electrode, The fuse element material is supported by being sandwiched between the first electrode and the second electrode in a bent state. The first electrode and the second electrode each have a claw portion at one end thereof, The fuse element material is sandwiched and supported in a manner that three or more claws of the first electrode and three or more claws of the second electrode are alternately arranged. Further possesses: a heating element for heating the fuse element material, a third electrode for supplying electricity to the heating element, and a conductive connecting portion connecting the heating element and the third electrode, The fuse element material is cut off by the heat generated by the energization to the heating element, and the connecting portion is separated from the third electrode, thereby stopping the energization to the heating element and the heat generation.

2. The protection element according to claim 1, wherein: A shearing force is applied to the fuse element material from the first electrode and the second electrode so that the fuse element material is sheared when an overcurrent flows.

3. The protection element according to claim 1, wherein: At least one of the first electrode and the second electrode is joined to the fuse element material by soldering.

4. The protection element according to claim 1, wherein: The tips of at least some of the claws included in the first electrode and the second electrode are bent toward the fuse element material.

5. The protection element according to claim 1, wherein: The first electrode has a spring characteristic, and the fuse element material is supported by being sandwiched between the first electrode in a bent state and the second electrode in a bent state.

6. The protection element according to claim 1, wherein: The fuse element material is composed of a laminate including a high melting point metal layer and a low melting point metal layer.

7. The protection element according to claim 6, wherein: The low melting point metal layer is made of Pb-free solder, and the high melting point metal layer is made of Ag or Cu or an alloy containing Ag or Cu as a main component.

8. The protection element according to claim 1, wherein: The first electrode and the second electrode each have an external terminal hole.

9. The protection element according to claim 1, wherein: A first terminal member is connected to the first electrode, and a second terminal member is connected to the second electrode.

10. The protection element according to claim 1, wherein: One end of the heating element is connected to the third electrode, and the other end of the heating element is connected to at least one of the fuse element material, the first electrode, and the second electrode.

11. The protection element according to claim 1, wherein: The third electrode is connected to a third terminal member.

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