KR20210090473A - Thermal fuse composite resistor - Google Patents

Abstract

The present invention relates to a thermal fuse composite resistor, and more particularly, to a thermal fuse composite resistor having an overheat prevention function. The thermal fuse composite resistor according to an embodiment of the present invention includes: a winding resistor including a winding rod extending in a first direction, and a wire wound on an outer circumferential surface of the winding rod; a thermal fuse unit connected to the winding resistor to block a current transmitted from the winding resistor at a predetermined temperature or higher; a conductive connection unit connecting the winding resistor and the thermal fuse unit in series; and a first terminal cap coupled to an end of the thermal fuse unit in the first direction, wherein the thermal fuse unit includes: an insulating body having an internal space penetrating in the first direction; a thermoplastic member provided between the conductive connection unit and the first terminal cap and at least partially melted at the predetermined temperature; a first spring provided between the conductive connection unit and the thermoplastic member to provide an elastic force to the thermoplastic member; and a second spring providing an elastic force opposing the first spring, wherein the conductive connection unit and the first terminal cap are electrically separated by melting of the thermoplastic member.

Description

Thermal fuse composite resistor

The present invention relates to a thermal fuse composite resistor, and more particularly, to a thermal fuse composite resistor having an overheat prevention function.

In general, high-power resistors are installed and used for voltage distribution or load resistance in electronic circuits of electronic products (eg, washing machines) that use high voltage and output. The main use of these high-power resistors is to be mounted on the power stage or the power conversion stage and applied to the circuit for the purpose of limiting inrush current, power distribution, and load power consumption.

Conventional high-power resistors are manufactured by simply connecting a commercially available thermal fuse to a wound resistor in series by means of electrical welding, etc., and have the disadvantage of increasing bulk because two parts are simply mechanically attached. Since they are somewhat spaced apart, there may be a reliability problem in that the thermal fuse does not work due to heat transfer problems during overheating. In addition, in the prior art, it was structurally difficult to automatically assemble the high-power resistor, so the high-power resistor was manually manufactured, which caused a problem in that the price of the parts was high.

Korean Patent Publication No. 10-2011-0035368

The present invention provides a thermal fuse composite resistor in which a winding resistor unit and a thermal fuse unit are integrated by a conductive connection unit.

A thermal fuse composite resistor according to an embodiment of the present invention includes: a winding resistor including a winding rod extending in a first direction and a wire wound on an outer circumferential surface of the winding rod; a thermal fuse unit connected to the winding resistance unit to block a current transmitted from the winding resistance unit at a predetermined temperature or higher; a conductive connection part connecting the winding resistor part and the thermal fuse part in series; and a first terminal cap coupled to an end of the thermal fuse unit in the first direction, wherein the thermal fuse unit includes: an insulating body having an internal space penetrating in the first direction; a thermoplastic member provided between the conductive connection part and the first terminal cap and at least partially melted at the predetermined temperature; a first spring provided between the conductive connection part and the thermoplastic member to provide an elastic force to the thermoplastic member; and a second spring providing an elastic force opposing the first spring, wherein the conductive connection part and the first terminal cap may be electrically separated by melting of the thermoplastic member.

The thermoplastic member may include: a fusible part including a metal melted at the predetermined temperature; and a flux portion provided in contact with the fusible portion, wherein the first spring and the second spring may be provided on both sides of the thermoplastic member in contact with the fusible portion, respectively.

The first spring and the second spring may be coated with a metal material including a metal included in the fusible part.

The length of the change in the first direction of the first spring due to the melting of the thermoplastic member may be smaller than the length of the thermoplastic member.

In the thermal fuse composite resistor according to the embodiment of the present invention, the winding resistance part and the thermal fuse part may be electrically connected through the conductive connection part, and when overheating due to overcurrent, surge, etc. occurs, the predetermined temperature or more occurs. By automatically opening the circuit when the thermal fuse part is disconnected by the thermoplastic member that is at least partially melted in the temperature fuse, other parts of the electronic device in which the thermal fuse composite resistor is installed are protected from overheating, thereby suppressing or preventing the occurrence of product defects. In addition, by integrating the winding resistance unit and the thermal fuse unit through the conductive connection unit, the volume of the thermal fuse composite resistor can be reduced compared to the conventional wire method in which the winding resistance and the thermal fuse are connected in series through a simple wire.

And since the space in which the thermoplastic member is placed can be separated from the winding resistance part by the conductive connection part, the thermal fuse part can be disconnected by the overall temperature of the thermal fuse composite resistor rather than the temperature of the wire that is easily heated and cooled. In addition, by providing pressure to the thermoplastic member through the elastic force of the first spring so that the thermal fuse part can be disconnected at the moment when the temperature reaches a predetermined temperature, the thermal fuse part can be disconnected quickly and effectively when the thermoplastic member is melted. And by using the second spring to provide an elastic force opposite to the first spring (or an elastic force in the opposite direction to the first spring), it is possible to ensure good electrical connection between the conductive connection part and the first terminal cap, and the conductive connection part and the second spring 1 Electrically close connection between the terminal caps can be maintained.

In addition, the thermoplastic member includes the fusible part and the flux part provided in contact with the fusible part, so that the thermoplastic member can be effectively melted, and the melted and contacted configuration (eg, the first spring and/or the second spring) is drawn. It can be pulled, and a plurality of components that are in contact with each side can be integrated (or soldered). Here, by interposing the thermoplastic member between the first spring and the second spring, disconnection of the thermal fuse part can be accurately made at the temperature of the thermal fuse composite resistor where disconnection is required, and the molten first spring and the second spring are attracted and conductive The first spring and the second spring may be integrated (or soldered) in a state in which they are spaced apart from the connection part and the first terminal cap, respectively, and thus the reliability of the thermal fuse composite resistor may be improved.

1 is a schematic diagram showing a thermal fuse composite resistor according to an embodiment of the present invention.
2 is a conceptual diagram for explaining an operation of a thermal fuse unit according to an embodiment of the present invention.
3 is a schematic view showing a modified example of a thermoplastic member including an electrically conductive member according to an embodiment of the present invention.
4 is a diagram showing a packaged thermal fuse composite resistor according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art completely It is provided to inform you. In the description, the same reference numerals are assigned to the same components, and the sizes of the drawings may be partially exaggerated in order to accurately describe the embodiments of the present invention, and the same reference numerals refer to the same elements in the drawings.

1 is a schematic diagram showing a thermal fuse composite resistor according to an embodiment of the present invention, FIG. 1 (a) is an exploded perspective view of the thermal fuse composite resistor, and FIG. 1 (b) is a cross-sectional view of the thermal fuse composite resistor.

Referring to FIG. 1 , a thermal fuse composite resistor 100 according to an embodiment of the present invention includes a winding rod 111 extending in a first direction, and a wire 112 wound on an outer circumferential surface of the winding rod 111 . A winding resistance unit 110 having a; a thermal fuse unit 120 connected to the winding resistance unit 110 to block the current transmitted from the winding resistance unit 110 above a predetermined temperature; a conductive connection unit 130 for connecting the winding resistance unit 110 and the thermal fuse unit 120 in a line; and a first terminal cap 140 coupled to an end of the thermal fuse unit 120 in the first direction.

The winding resistance unit 110 may include a winding rod 111 extending in the first direction and a wire 112 wound on the outer circumferential surface of the winding rod 111, and protect against overcurrent as well as external surges such as lightning. ) can be absorbed.

The winding rod 111 may extend in the first direction and may be made of an insulating material such as ceramic (eg, alumina) or plastic (eg, synthetic resin). At this time, the winding rod 111 may have a rod shape, and may have a structure in which one side is open and the other side is closed, or may have a cylinder shape through which both sides are opened and penetrated. In the case of , at least a portion of the thermal fuse unit 120 may be provided in the inner space of the winding rod 111 through an opening formed on at least one side of the winding rod 111 .

The wire 112 may be wound in a coil shape on the outer peripheral surface of the winding rod 111 , and an end (or one end) of the first direction may be electrically connected to the conductive connection unit 130 , and the first direction A second direction end (or the other end) parallel to and opposite to may be electrically connected to the second terminal cap 150 . Here, the wire 112 may be made of a resistance wire such as Ni-Cr, Ni-Fe-Cr, and may serve as a surge protection by absorbing a surge. At this time, when a surge flows into the winding resistance unit 110 , the wire 112 may absorb the surge and generate heat. Meanwhile, a surface protection layer may be formed by surface coating the wire 112 with an insulating resin or inorganic paint, or a surface protection package may be formed using a heat shrinkable tube or a plastic case to protect the wire 112 .

The thermal fuse unit 120 may be connected to the winding resistance unit 110 , and may block the current transmitted from the winding resistance unit 110 at a predetermined temperature or higher. In this case, the thermal fuse unit 120 may be connected to the first end (or one end) of the winding resistance unit 110 . For example, the thermal fuse unit 120 may be at least partially melted above the predetermined temperature, and is provided between the conductive connection unit 130 and the first terminal cap 140 to reach the predetermined temperature. It is possible to block the electrical connection between the conductive connection part 130 and the first terminal cap 140 .

The conductive connection unit 130 may have electrical conductivity, and may connect the winding resistance unit 110 and the thermal fuse unit 120 in a line, and the winding resistance unit 110 and the thermal fuse unit 120 may be electrically connected. (or connect) can be made. For example, the conductive connection unit 130 is interposed between the winding resistance unit 110 and the thermal fuse unit 120 to physically connect the winding resistance unit 110 and the thermal fuse unit 120 and electrically at the same time. can connect The conductive connection unit 130 connects at least a portion of the thermal fuse unit 120 to the end of the winding rod 111 in the first direction by attaching the thermal fuse unit 120 to the winding resistance unit 110 and the thermal fuse unit 120 . can be integrated into a straight line.

For example, the conductive connection part 130 may be connected to the end of the winding rod 111 in the first direction, and may be electrically connected to the end of the wire 112 in the first direction, and of the thermal fuse unit 120 . It may be connected to the second direction end (or the other end). Current transferred from the second terminal cap 150 to the wire 112 may flow to the conductive connection part 130 , and may be transferred from the conductive connection part 130 to the thermal fuse part 120 . Here, the conductive connection part 130 may have a cap shape at both ends coupled to the first direction end of the winding rod 111 and the second direction end of the thermal fuse unit 120 , and the winding rod ( 111) and the second direction end of the thermal fuse part 120 may be respectively covered by the conductive connection part 130 and coupled thereto. That is, at both ends of the conductive connection part 130, a support surface on which the winding rod 111 and the thermal fuse part 120 are supported, respectively, and sidewalls extending outwardly (or vertically) from the support surface around the support surface are provided. Each coupling end may be provided, and the first direction end of the winding rod 111 and the second direction end of the thermal fuse unit 120 may be inserted into the coupling end to be coupled. Through this, the winding resistance unit 110 simply by pushing the first direction end of the winding rod 111 and the second direction end of the thermal fuse unit 120 into the coupling ends of both ends of the conductive connection unit 130, respectively. , the thermal fuse unit 120 and the conductive connection unit 130 may be integrally assembled (or combined).

In addition, since the space in which the thermoplastic member 122 is placed can be separated from the winding resistor 110 by the conductive connection part 130, the temperature of the thermal fuse composite resistor 100 is not the temperature of the wire 112 that is easily heated and cooled. The thermal fuse unit 120 may be disconnected due to the overall temperature. The wire 112 can be easily heated so that when all of the temperature of the wire 112 is transferred to the thermoplastic member 122, even if the overall temperature of the thermal fuse composite resistor 100 does not reach the predetermined temperature, the wire As long as the temperature of 112 exceeds the predetermined temperature, the thermoplastic member 122 may be melted and the thermal fuse unit 120 may be disconnected. In addition, the internal space of the winding rod 111 does not emit heat and accumulates so that the temperature may rise faster. When the thermoplastic member 122 is disposed in the internal space of the winding rod 111, the wire 112 Even before the temperature reaches the predetermined temperature, the temperature of the inner space of the winding rod 111 may reach the predetermined temperature and the thermoplastic member 122 may be melted. Due to this, the temperature fuse unit 120 may not respond (or disconnect) at the moment when the disconnection of the thermal fuse unit 120 is required at which the overall temperature of the thermal fuse composite resistor 100 becomes the predetermined temperature, and an unnecessary moment The thermal fuse unit 120 may be disconnected. However, this problem can be solved by separating the space in which the thermoplastic member 122 is placed from the winding resistor 110 through the conductive connection part 130 .

Recently, a composite resistor with an overheat protection function has been released on the market. However, the conventional composite resistor simply connects a commercially available thermal fuse to a winding resistor in series through a wire by manual methods such as electric welding. As a manufactured product, there is a problem in that the volume of the composite resistor increases and the price of the component increases.

However, in the thermal fuse composite resistor 100 of the present invention, the winding resistance unit 110 and the thermal fuse unit 120 through the conductive connection unit 130 interposed between the winding resistance unit 110 and the thermal fuse unit 120 . ), it is possible to reduce the volume of the thermal fuse composite resistor 100 compared to the conventional wire method in which the winding resistor and the thermal fuse are connected in series through a simple wire.

The first terminal cap 140 may be coupled to the first end (or one end) of the thermal fuse unit 120 , and may be electrically connected to the thermal fuse unit 120 , and the second terminal cap 150 . The current transferred to the wire 112 of the winding resistance unit 110 may flow to the first terminal cap 140 through the conductive connection unit 130 and the thermal fuse unit 120 . For example, the first terminal cap 140 may include a coupling part, and the coupling part is formed in a cup shape so that it can be easily matched and fitted to the end of the thermal fuse part 120 in the first direction, They may also be joined by a mechanical forced press-fitting method.

On the other hand, the thermal fuse composite resistor 100 of the present invention is provided at the second direction end (or the other end) of the winding rod 111 and a second terminal cap electrically connected to the second direction end portion of the wire 112 . (150); may further include. The second terminal cap 150 may be provided at the end of the winding rod 111 in the second direction to be electrically connected to the end of the wire 112 in the second direction, and power (or current) may be applied from the outside. and may be electrically connected to the second direction end of the wire 112 to transmit a current to the wire 112 . For example, the second terminal cap 150 may be provided symmetrically (or opposite to) the first terminal cap 140 , and may have the same shape as the first terminal cap 140 .

And the thermal fuse part 120 has an insulating body 121 having an internal space penetrated in the first direction; a thermoplastic member 122 provided between the conductive connection part 130 and the first terminal cap 140 and at least partially melted at the predetermined temperature; a first spring 123 provided between the conductive connection part 130 and the thermoplastic member 122 to provide an elastic force to the thermoplastic member 122; and a second spring 124 providing an elastic force opposing the first spring 123 . The body 121 may be insulating, and may be made of an insulating material (eg, ceramic, plastic, etc.). In addition, the body 121 may extend in the first direction, may have an inner space penetrated in the first direction, and a thermoplastic member 122 may be provided in the inner space of the body 121 .

The thermoplastic member 122 may be provided between the conductive connection part 130 and the first terminal cap 140 , and may include a thermoplastic material and may be at least partially melted at the predetermined temperature, and then melted to the thermal fuse part. 120 may be disconnected or fusing. Here, the thermoplastic material may be a material that is melted at a predetermined temperature. For example, the thermoplastic member 122 may be made of a conductive material, and may be made of a conductive metal or metal alloy having a melting point lower than 250° C., or low-temperature solder (eg, Sn-Bi, Sn-In). Here, the conductive metal may be tin (Sn), and tin has a melting point (or melting point) of 231.93 °C, and is a metal having a melting characteristic at a temperature of about 232 °C or higher. And the metal alloy may be a tin alloy consisting of an alloy of tin and one or more metals selected from Ag, Cu, Zn, Cd, Sb, Bi, In, Ga and Pb, Sn-Cu-based, Sn-Ag-based, Sn -Ag-Cu, Sn-Ag-Bi, Sn-Ag-Bi-In, Sn-Ag-Zn, Sn-Zn, Sn-Bi, Sn-In, Sn -Bi, Sn-Zn, Sn-Be, Sn-Ag-Cu-Bi, Sn-Bi-Ag, Sn-Bi-In, and the like. Here, the Sn-Ag-Cu-Bi alloy may have a melting point of about 205 to 220 °C, and the Sn-Bi-Ag alloy may have a melting point of about 130 to 180 °C. At this time, in the case of using a Sn-Bi-In alloy, the thermoplastic member 122 having a melting point of about 100° C. may be manufactured.

The first spring 123 may be provided between the conductive connection part 130 and the thermoplastic member 122 , and may provide elastic force to the thermoplastic member 122 . That is, the first spring 123 may be compressed and provided between the conductive connection part 130 and the thermoplastic member 122 , and may provide pressure to the thermoplastic member 122 by an elastic force. Here, at least one end (eg, the second direction end) of the first spring 123 may be fixed, or at least one end may be in contact, and the first spring 123 may be attached to the thermoplastic member 122 by an elastic force. By providing pressure in the direction, the disconnection of the thermal fuse unit 120 can be quickly and effectively made when the thermoplastic member 122 is melted. That is, by physically separating (or cutting) or collapsing the thermoplastic member 122 that is electrically connected through a physical connection, the thermal fuse unit 120 can be disconnected, and the first spring 123 is removed. By providing a pressure in the first direction to the thermoplastic member 122 through the thermoplastic member 122 may be physically separated or collapsed well. On the other hand, the thermoplastic member 122 is connected to the first terminal cap 140 by making the thermoplastic member 122 electrically close to the first terminal cap 140 through the first spring 123 . It can be effectively connected.

If the first spring 123 is not used, the instantaneous response of the thermal fuse unit 120 may not be obtained. In the thermal fuse unit 120 , when the predetermined temperature is exceeded, the thermoplastic member 122 is melted to instantaneously disconnect the conductive connection unit 130 and the first terminal cap 140 (or the thermal fuse unit). However, since the thermoplastic member 122 melts gradually rather than instantaneously (or at once) above the predetermined temperature, the temperature of the thermal fuse composite resistor 100 exceeds the predetermined temperature. The unit 120 may not be disconnected. However, when the first spring 123 is used, the first spring 123 applies pressure to the thermoplastic member 122 to rapidly collapse or cut the thermoplastic member 122 when the thermoplastic member 122 is melted, It is possible to momentarily disconnect between the conductive connection part 130 and the first terminal cap 140 , and obtain an instantaneous response of the thermal fuse part 120 .

The second spring 124 may provide an elastic force opposite to the first spring 123 (or an elastic force in the opposite direction to the first spring), and the first spring 123 and the first terminal cap 140 may have an elastic force opposite to the first spring 123 . It may be provided between or inside the first spring 123 . For example, the second spring 124 may be provided between the thermoplastic member 122 and the first terminal cap 140 , and is supported (or fixed) by the first terminal cap 140 to the thermoplastic member 122 . ) to the first spring 123 and the opposite direction (eg, a second direction parallel to and opposite to the first direction) may apply (or provide) pressure. At this time, the second spring 124 may directly contact (or connect) to the first terminal cap 140 , or provide a force (or pressure) for bringing the thermoplastic member 122 into close contact with the first terminal cap 140 . In addition, the first spring 123 and/or the electrically conductive member 125 for electrically connecting the thermoplastic member 122 and the conductive connection part 130 may provide a force to adhere to the conductive connection part 130, It may be a coil spring.

When the first spring 123 provides pressure in the first direction, the first spring 123 and/or the electrically conductive member 125 may not be properly connected to the conductive connection unit 130 . That is, since the first spring 123 provides pressure in the first direction, not in the second direction, toward the conductive connection part 130 , the first spring 123 and/or the electrically conductive member 125 are connected to the conductive connection part. Since it is not in close contact with the 130 and the close contact is not made, a connection failure between the first spring 123 and/or the electrically conductive member 125 and the conductive connection part 130 may occur. However, the force (eg, elastic force or pressure) in the second direction for bringing the first spring 123 and/or the electrically conductive member 125 into close contact with the conductive connection part 130 through the second spring 124 . By providing, the first spring 123 and/or the electrically conductive member 125 can be in close contact with the conductive connection part 130 to be in close contact, and even if the first spring 123 is used, the first spring 123 ) and/or the electrically conductive member 125 may be effectively and well connected to the conductive connection part 130 . In addition, the thermoplastic member 122 may be effectively and well connected to the first terminal cap 140 . Accordingly, a closer electrical connection may be maintained between the conductive connection part 130 , the thermoplastic member 122 , and the first terminal cap 140 .

Figure 2 is a conceptual diagram for explaining the operation of the thermal fuse unit according to an embodiment of the present invention, Figure 2 (a) shows a thermal fuse composite resistor provided horizontally, Figure 2 (b) is a thermal fuse composite provided vertically In the resistor, the thermal fuse part is arranged above, and FIG. 2(c) is a diagram in which the thermal fuse part is arranged below in the vertically provided thermal fuse composite resistor.

Referring to FIG. 2 , the conductive connection part 130 and the first terminal cap 140 may be electrically separated by melting of the thermoplastic member 122 . For example, due to the molten position of the thermoplastic member 122, the first spring 123 and/or the electrically conductive member 125 and the conductive connection part 130 or the second spring 124 and/or the electrically conductive member ( 125) and the first terminal cap 140 are spaced apart so that the conductive connection part 130 and the first terminal cap 140 can be electrically separated, and the first spring 123, the first spring 123, 2 The first spring 123 , the second spring 124 and/or the electrically conductive member with the conductive connecting portion 130 or the first terminal cap 140 by moving the spring 124 and/or the electrically conductive member 125 . 125 may be disconnected.

Here, the thermoplastic member 122 may include a fusible portion 122a including a metal melted at the predetermined temperature; and a flux portion 122b provided in contact with the fusible portion 122a. The fusible portion 122a may include a metal that is melted at the predetermined temperature, may include a metal such as tin or a tin alloy, and may be melted (or melted) at the predetermined temperature to block electrical connection. .

The flux portion 122b may be provided in contact with the fusible portion 122a, may be provided mixed with the fusible portion 122a, or may be provided separately from the fusible portion 122a. For example, the flux portion 122b may be provided in the fusible portion 122a and may be provided independently of the fusible portion 122a without being uniformly mixed in the fusible portion 122a. At this time, the flux part 122b may be accommodated in the fusible part 122a, may be inserted into the center of the fusible part 122a, and the flux part 122b of the core may be accommodated in the fusible part 122a. The fusible part 122a and the core-shell structure may be formed in a wrap-around shape. The flux portion 122b may promote the melting of the fusible portion 122a, and may allow the thermoplastic member 122 to be effectively melted. In addition, the flux portion 122b may improve the wettability (the degree of spreading on the surface) of the melt 122c of the molten thermoplastic member 122 to agglomerate the melt 122c of the thermoplastic member 122, and contact It is possible to attract other components (eg, the first spring or the second spring) that have been made, and it is possible to integrate (or solder) a plurality of components that are solidified and are in contact with both sides, respectively. That is, the flux portion 122b increases the force (eg, surface tension, surface energy) acting between the melt 122c of the thermoplastic member 122 and air (eg, the atmosphere) to increase the thermoplastic member 122 . ), the wettability of the melt 122c may be lowered, and the melt 122c of the thermoplastic member 122 may be aggregated in a round shape, and may be solidified to solder surrounding components. For example, the flux unit 122b may be made of a flux (or solvent) such as chloride, fluoride, resin, pine resin, or the like.

When the thermoplastic member 122 is formed by simply mixing flux with a metal such as tin or a tin alloy, electrical conductivity and hardness are inevitably lower than those made of only metal. That is, when the flux is mixed, the flux material (or component) acts as an impurity to increase the electric resistance of the thermoplastic member 122 and lower the electric conductivity. In addition, the flux material has a lower hardness than the metal, and when mixed with a metal, the metal ratio in the thermoplastic member 122 is lowered. Therefore, the overall hardness of the thermoplastic member 122 is inevitably lower than that of the case made of only the metal. When the electrical conductivity of the thermoplastic member 122 is low, it is impossible to smoothly (or effectively) the flow of current between the conductive connection part 130 and the first terminal cap 140 , and heat generation due to electrical resistance is prevented. may occur. When the hardness of the thermoplastic member 122 is low, the thermoplastic member 122 is pressed by the elastic force (or elongation force) of the first spring 123 and/or the second spring 124 and the first spring 123 and / or the second spring 124 is not stably supported, so that sufficient elastic force cannot be provided toward each of the conductive connection part 130 and the first terminal cap 140, and the first spring 123 and the conductive connection part 130 Between and/or the second spring 124 and the first terminal cap 140 are not in close contact (or close contact is not made), and the electrical connection between the conductive connection part 130 and the first terminal cap 140 is stable. can't make it

And when the thermoplastic member 122 is formed by mixing the flux with the metal, since the size of the thermoplastic member 122 provided to each thermal fuse composite resistor 100 is very small, each thermal fuse composite resistor 100 It becomes very difficult to uniformly adjust the ratio of the flux contained in each of the thermoplastic members 122 to provide each of them.

In other words, since the flux has a low melting point and the proportion contained in the thermoplastic member 122 is increased, the melting point of the thermoplastic member 122 is lowered, and thus the flux is contained in a small proportion (or only a small amount) in the thermoplastic member 122 . . That is, the flux lowers the melting point of the thermoplastic member 122 and does not electrically separate the conductive connection part 130 and the first terminal cap 140 at the predetermined temperature (or a desired temperature), but is lower than the predetermined temperature. At the temperature, the conductive connection part 130 and the first terminal cap 140 are electrically separated, and the reliability of the thermal fuse composite resistor 100 that disconnects the thermal fuse part 120 at the predetermined temperature may be reduced. , and accordingly, the flux is contained in the thermoplastic member 122 in a small proportion. Because the flux is contained in a small proportion in the thermoplastic member 122, even if the flux is well dispersed in the mixture (or mixed solution) of the metal and the flux, it is the same for each thermoplastic member 122 formed of the mixture of a small amount of the metal and the flux. It is very difficult (or impossible) to incorporate the flux in proportions.

When the flux content ratio of each thermoplastic member 122 is different, the melting point of each thermoplastic member 122 varies according to the flux content ratio, and each thermal fuse composite resistor 100 has a thermal fuse. The temperature at which the part 120 is disconnected is different, so that the operational reliability of the thermal fuse composite resistor 100 may be deteriorated.

However, when the thermoplastic member 122 is formed by separating the fusible part 122a and the flux part 122b, the ratio of the fusible part 122a and the flux part 122b in each thermoplastic member 122 is constant. It can be maintained, and the formation of the thermoplastic member 122 can be easy. In addition, the fusible part 122a and the flux part 122b are separated, so that the fusible part 122a can maintain the hardness when it is made of only metal, and can have electrical conductivity (when it is made of only metal), Current may flow (or conduct electricity) along the fusible portion 122a. Accordingly, it may be preferable to form the thermoplastic member 122 by separating the fusible part 122a and the flux part 122b.

At this time, the first spring 123 and the second spring 124 are in contact with the fusible portions 122a on both sides (eg, the second direction side and the first direction side) of the thermoplastic member 122 , respectively. may be provided. When the first spring 123 and the second spring 124 are provided on both sides of the thermoplastic member 122 , respectively, the first spring 123 applies pressure to the thermoplastic member 122 in the first direction to form a second The spring 124 may be brought into close contact with the first terminal cap 140 , and the second spring 124 may be formed by applying pressure to the thermoplastic member 122 in the second direction parallel to and opposite to the first direction. 1 The spring 123 may be in close contact with the conductive connection part 130 . Accordingly, close contact may be made between the conductive connection part 130, the first spring 123, the thermoplastic member 122, the second spring 124, and the first terminal cap 140, and the conductive connection part 130 and the first terminal cap 140 may be in close contact. It is possible to electrically connect between the first terminal caps 140 and effectively between the conductive connecting portion 130 , the first spring 123 , the thermoplastic member 122 , the second spring 124 , and the first terminal cap 140 . can be connected.

In addition, since the first spring 123 and the second spring 124 may be symmetrically disposed on both sides of the thermoplastic member 122 , it is possible to provide elastic forces having the same size and opposite directions only, and accordingly, the conductive connection part Since the adhesive force between 130 and the first spring 123 and the adhesive force between the second spring 124 and the first terminal cap 140 can be the same, the conductive connection part 130, the first spring 123, and the thermoplastic member ( 122), a stable (or balanced) connection can be made between the second spring 124 and the first terminal cap 140, and the same spring can be used with the first spring 123 and the second spring 124. can also be used.

In addition, since the flux portion 122b can agglomerate the melt 122c of the molten thermoplastic member 122, the first spring 123 and the second spring are in contact with both sides while the thermoplastic member 122 is melted. By pulling the 124 toward each other, when the thermoplastic member 122 is melted, the first spring 123 and the second spring 124 are spaced apart from the conductive connection part 130 and the first terminal cap 140, respectively. (or separated), the disconnection of the thermal fuse unit 120 can be effectively made, and the thermal fuse unit that operates (or operates) above the predetermined temperature due to the occurrence of overheat due to overcurrent, surge, etc. 120) can be improved.

On the other hand, the first spring 123 and the second spring 124 may contact the fusible portion 122a, and the first spring 123 and the second spring 124 have a low electrical conductivity flux portion 122b. Instead of being made of metal, it can be electrically connected to the fusible part 122a having high electrical conductivity, and the current can be smoothly flowed between the conductive connection part 130 and the first terminal cap 140 .

And the first spring 123 and the second spring 124 may be coated with a metal material including a metal included in the fusible part 122a, may be coated with the metal included in the fusible part 122a, The fusible portion 122a may be coated with the same (metal) material as the fusible portion 122a including the metal. For example, the first spring 123 and the second spring 124 may be coated with the same metal material as the fusible portion 122a. Since the coating layers of each of the first spring 123 and the second spring 124 made of the same metal material as the fusible part 122a are in contact with the fusible part 122a, respectively, the first spring 123 and the fusible part 122a Contact resistance may be reduced between and between the second spring 124 and the fusible portion 122a, and the current between the conductive connection portion 130 and the first terminal cap 140 may flow smoothly. can That is, since the contact surface of the fusible part 122a and the contact surface of each of the first spring 123 and the second spring 124 are made of the same metal material, the conductive connection part 130 and the first spring 123 are in contact or When the two springs 124 and the first terminal cap 140 come into contact, the same material contacts to form an interface, and thus different materials may contact each other to have a lower contact resistance than the contact resistance generated at the interface.

In addition, when the first spring 123 and the second spring 124 are coated with a metal material including a metal included in the fusible portion 122a, the coating layer of each of the first spring 123 and the second spring 124 It is melted together with the fusible part 122a at this predetermined temperature and the melt 122c of the thermoplastic member 122 fills the first spring 123 and the second spring 124 to be integrated (or soldered). The coating layer may secure the high electrical conductivity of the first spring 123 and the second spring 124, and then increase the electrical conductivity of the first spring 123 and the second spring 124 by melting the coating layer. It can be reduced or eliminated, and electrical short circuit (or disconnection) can be effectively made above the predetermined temperature. Accordingly, the reliability of the thermal fuse unit 120 that is electrically short-circuited above the predetermined temperature can be further improved.

Here, the first spring 123 and the second spring 124 are made of an insulating material and only the coating layer may have electrical conductivity. The first spring 123 and the second spring 124 may also have electrical conductivity so as to secure the electrical conductivity of the second spring 124 . For example, the first spring 123 and the second spring 124 may be made of stainless steel (eg, SUS, etc.), and the first spring 123 and the second spring (eg, tin, tin alloy, etc.) 124 ), the first spring 123 and the second spring 124 may be coated with a material having higher electrical conductivity than the material (eg, stainless steel).

Meanwhile, the volume ratio of the flux portion 122b of the thermoplastic member 122 may be 1 to 30%. When the volume ratio of the flux portion 122b is less than 1%, the effect of agglomeration of the melt 122c of the thermoplastic member 122 is insignificant, and when the thermoplastic member 122 is melted, the first spring 123 and the second spring ( It may not be effective to separate the 124 from the conductive connection part 130 and the first terminal cap 140, respectively, and when the volume ratio of the flux part 122b is greater than 30%, the melting point of the thermoplastic member 122 ( too), the melting temperature of the thermoplastic member 122 may vary greatly depending on the position of the flux portion 122b or heat transfer (or thermal conductivity) of the fusible portion 122a.

3 is a schematic view showing a modified example of a thermoplastic member including an electrically conductive member according to an embodiment of the present invention, FIG. 3 (a) is a normal state of the thermal fuse part in which the second spring is disposed inside the first spring. 3(b) shows the disconnection state of the thermal fuse part in which the second spring is disposed inside the first spring, and FIG. 3(c) shows the second spring is disposed between the thermoplastic member and the first terminal cap. The normal state of the thermal fuse part is shown, and FIG. 3(d) shows the disconnection state of the thermal fuse part in which the second spring is disposed between the thermoplastic member and the first terminal cap.

Referring to FIG. 3 , the thermal fuse unit 120 is provided in the inner space of the body 121 and further includes an electrically conductive member 125 for electrically connecting the conductive connecting portion 130 and the thermoplastic member 122 . can The electrically conductive member 125 may be provided in the inner space of the body 121 , and may have electrical conductivity to electrically connect the conductive connection part 130 and the thermoplastic member 122 . For example, the electrically conductive member 125 may connect between the thermoplastic member 122 electrically connected to the first terminal cap 140 and the conductive connection part 130 to allow current to flow. Here, as shown in FIG. 3 , a part of the electrically conductive member 125 may be provided (or inserted) inside (or inside) the first spring 123 , and the first direction of the first spring 123 . The end (or one end) may have a support end supported directly or indirectly. At this time, the second direction end (or the other end) of the first spring 123 may be supported by being in contact with the conductive connection part 130 , and the first spring 123 may be fixed to the conductive connection part 130 and a thermoplastic member ( While pushing the electrically conductive member 125 (ie, the support end of the electrically conductive member) toward the 122), pressure may be applied to the thermoplastic member 122 in the first direction. When the thermoplastic member 122 is melted above the predetermined temperature, the electrically conductive member 125 moves by the elongation of the first spring 123 according to the melting of the thermoplastic member 122 and is separated from the conductive connection part 130 . may be separated (or spaced apart).

Here, the second spring 124 may be provided by being inserted into the electric conductive member 125 as shown in FIGS. 3(a) and 3(b), and FIGS. 3(c) and 3(d). As such, it may be provided interposed between the thermoplastic member 122 and the first terminal cap 140 . 3(a) and 3(b), when the second spring 124 is inserted into the electrically conductive member 125 and provided, the surface in contact with the thermoplastic member 122 is open. As an accommodation space in which the second spring 124 can be accommodated in the central portion of the electrically conductive member 125 , a pit or a hole may be formed, and when the thermoplastic member 122 is melted, the thermoplastic member The melt 122c of (122) can be filled in the groove or hole, so that the thermoplastic member 122 is melted and flows down along the inner wall of the inner space of the body 121. The melt 122c of the thermoplastic member 122 Accordingly, it is possible to prevent the conductive connection 130 and the first terminal cap 140 from being electrically connected again. In addition, since an accommodation space in which the melt 122c of the thermoplastic member 122 can be accommodated may not be formed in the inner space of the body 121 , the volume of the body 121 may be reduced, and the overall temperature fuse part The volume of the 120 and/or the thermal fuse composite resistor 100 may be reduced. At this time, the second spring 124 is supported in contact with the thermoplastic member 122 and pushes the electrically conductive member 125 toward the conductive connection part 130, so that the electrical conductive member 125 and the conductive connection part 130 are in close contact ( or connection) may be made, and a stable electrical connection may be made between the conductive connection part 130 and the first terminal cap 140 .

Meanwhile, the first spring 123 may be an insulator or may have electrical conductivity. When the first spring 123 has electrical conductivity, when the thermoplastic member 122 is melted, the first spring 123 and Insulation provided (or interposed) between the support end of the electrically conductive member 125 and the first end of the first spring 123 so that the thermal fuse unit 120 is not electrically connected between the electrically conductive members 125 . A member 126 may be further included. The insulating member 126 may be provided between the supporting end of the electrically conductive member 125 and the first end of the first spring 123 , and the insulating member 126 is disposed on the supporting end of the electrically conductive member 125 . and the first spring 123 is supported on the insulating member 126 , so that the first spring 123 may be indirectly supported by the supporting end of the electrically conductive member 125 . For example, the insulating member 126 may be an insulating ring having a ring shape, and a portion of the electrically conductive member 125 provided inside the first spring 123 forms a hollow portion of the insulating member 126 . Penetrating, the insulating member 126 may be provided on the support end of the electrically conductive member 125 (only). Accordingly, even when the first spring 123 has electrical conductivity, electrical connection between the first spring 123 and the electrically conductive member 125 is prevented from being made, so that when the thermoplastic member 122 is melted, the first spring ( 123 ) and the electrically conductive member 125 are electrically connected to each other to prevent the electrical connection between the conductive connection part 130 and the first terminal cap 140 from being maintained. In addition, the second spring 124 may be an insulator or may have electrical conductivity in the modified example of FIGS. 3 ( a ) and 3 ( b ), but the stability of the electrically conductive member 125 and the thermoplastic member 122 . It may be desirable to have electrical conductivity for electrical connection, and in the case of a modification of FIGS. 3 ( c ) and 3 ( d ), electrically connecting between the thermoplastic member 122 and the first terminal cap 140 . to have electrical conductivity.

In addition, the length of the first direction change of the first spring 123 due to the melting of the thermoplastic member 122 may be smaller than the length of the thermoplastic member 122 . After the thermoplastic member 122 is melted, when the length of change of the first spring 123 in the first direction is equal to or greater than the length of the thermoplastic member 122, the first spring 123 moves to the second spring 124, It is electrically connected to at least one of the electrically conductive member 125 , the melt 122c of the thermoplastic member 122 , and the first terminal cap 140 , and is electrically connected between the conductive connection part 130 and the first terminal cap 140 . Electrically connected, disconnection of the thermal fuse unit 120 may not be made, and the reliability of the thermal fuse unit 120 that is electrically short-circuited above the predetermined temperature may be reduced. In addition, if the first direction change length of the first spring 123 due to melting of the thermoplastic member 122 is greater than or equal to the length of the thermoplastic member 122 , the elastic force of the first spring 123 is the second spring 124 . may mean greater than the elastic force of the second spring 124, the second spring 124 is relatively small, so the adhesive force between the conductive connection part 130 and the first spring 123 or the adhesive force between the conductive connection part 130 and the electrically conductive member 125 This inevitably becomes smaller, and a stable electrical connection cannot be made between the conductive connection part 130 and the first spring 123 or between the conductive connection part 130 and the electrically conductive member 125 . Accordingly, by making the length of the change in the first direction of the first spring 123 due to the melting of the thermoplastic member 122 smaller than the length of the thermoplastic member 122 , the conductive connection part 130 when the thermoplastic member 122 is melted. It is possible to prevent the electrical connection between the and the first terminal cap 140 again, and between the conductive connection part 130 and the first spring 123 or between the conductive connection part 130 and the electrically conductive member 125 is sufficient. Adhesion can be provided.

For example, the first spring 123 and the second spring 124 may be provided in a compressed state, and the compressed length of the first spring 123 (or the first spring by melting of the thermoplastic member) The sum of the length of change of ) and the compressed length of the second spring 124 (or the length of change of the second spring due to melting of the thermoplastic member) may be smaller than the length of the thermoplastic member 122 . When the sum of the compressed length of the first spring 123 and the compressed length of the second spring 124 is equal to or greater than the length of the thermoplastic member 122 , the compression is performed even if the thermoplastic member 122 is melted at the predetermined temperature or higher. As the first spring 123 and the second spring 124 return to their original state (or extend), they come into contact with each other, so that the electrical connection between the conductive connection part 130 and the first terminal cap 140 can be maintained. , even if the temperature of the electronic device rises above the predetermined temperature due to overheating caused by overcurrent, surge, etc., the circuit cannot be short-circuited (or disconnected), so other parts of the electronic device cannot be protected from overheating, and product defects occur cannot be suppressed or prevented. Accordingly, by making the sum of the compressed length of the first spring 123 and the compressed length of the second spring 124 smaller than the length of the thermoplastic member 122, when the thermoplastic member 122 is melted, the first spring ( 123 ) and the second spring 124 may be prevented from electrically connecting the conductive connection part 130 and the first terminal cap 140 .

4 is a diagram showing a packaged thermal fuse composite resistor according to an embodiment of the present invention. FIG. 4 (a) shows a cement resistor, and FIG. 4 (b) shows a resistor coated with insulation.

Referring to FIG. 4 , the thermal fuse composite resistor 100 of the present invention includes a winding resistance unit 110 , a thermal fuse unit 120 , a conductive connection unit 130 , a first terminal cap 140 , and a second terminal cap ( 150) of at least one outer protection unit 160 provided on the outer surface; may further include. The outer protection part 160 may be made of a cement-based inorganic material, as shown in FIG. 4( a ), and the winding resistance part 110 , the thermal fuse part 120 , the conductive connection part 130 , the first terminal cap 140 . and a resistance assembly of the second terminal cap 150 may be molded. For example, the resistance assembly is prepared (or put) inside the case 161, and the insulating molding solution 162 made of a cementitious inorganic material is filled (or supplied) inside the case 161 to harden it. have. Here, the case 161 may be formed of a ceramic material (eg, cordierite and alumina-based ceramics), and thus may have a non-combustible structure, and may be used in circuits with high power consumption because it can withstand high temperatures well. In addition, at least one fixing groove is formed in the upper end of the case 161 at regular intervals, so that the resistor assembly can be fixed at a predetermined position inside the case 161 . In addition, the resistor assembly may be provided inside the case 161, and by interfering with the flow of current in a circuit (eg, electronic device) including the thermal fuse composite resistor 100, an appropriate amount of current It can function to regulate the flow in the circuit. In addition, the insulating molding liquid 162 may be manufactured by making a ceramic inorganic powder in the form of a paste, and the resistance assembly may be molded.

Here, the cement resistance is also referred to as a ceramic resistance, and may be manufactured in a form in which the resistance assembly is put in a case 161 made of ceramic for structural insulation and heat dissipation and cured with an insulation molding liquid 162 . The cement resistor has a non-combustible structure because the resistor assembly is contained in a ceramic case 161, has excellent withstand voltage characteristics and withstands high temperatures well, so it can be mainly used in circuits with high power consumption.

The outer protection part 160 may be formed by coating (or painting) with an insulating paint, as shown in FIG. 4(b), may be formed of a silicone material (eg, liquid silicone, etc.), and may be formed of a wire by overcurrent When the (112) is broken, it can prevent the fragments from being emitted. In addition, the outer protective part 160 may be formed through painting, lacquering, etc., may be formed of a material having high heat resistance, and powder is applied to a phenolic epoxy resin. It may be formed of a mixed (or injected) flame retardant paint. Here, the outer protection unit 160 may be provided on at least the outer surface of the winding resistance unit 110 , insulate the wire 112 from the outside, and protect the outside of the winding resistance unit 110 . On the other hand, at least a portion of the resistance assembly may be simply inserted into the heat-shrinkable tube to form the outer protection part 160 .

As such, in the present invention, the winding resistance part and the thermal fuse part can be electrically connected through the conductive connection part, and when the temperature is higher than a predetermined temperature due to overheating due to overcurrent or surge, the thermoplastic member is at least partially melted at a predetermined temperature. By automatically opening the circuit when the thermal fuse part is disconnected, it is possible to suppress or prevent the occurrence of product defects by protecting other parts of the electronic device in which the thermal fuse composite resistor is installed from overheating. In addition, the volume of the thermal fuse composite resistor can be reduced compared to the conventional wire method of simply connecting the winding resistor and the thermal fuse in series through a wire by integrating the winding resistance unit and the thermal fuse unit through the conductive connection unit. And since the space in which the thermoplastic member is placed can be separated from the winding resistance part by the conductive connection part, the thermal fuse part can be disconnected by the overall temperature of the thermal fuse composite resistor rather than the temperature of the wire that is easily heated and cooled. In addition, by providing pressure to the thermoplastic member through the elastic force of the first spring so that the thermal fuse part can be disconnected at the moment when the temperature reaches a predetermined temperature, the thermal fuse part can be disconnected quickly and effectively when the thermoplastic member is melted. And by using the second spring to provide an elastic force opposing the first spring, it is possible to make a good electrical connection between the conductive connection part and the first terminal cap, and to maintain an electrically close connection between the conductive connection part and the first terminal cap have. In addition, the thermoplastic member includes the fusible part and the flux part provided in contact with the fusible part, so that the thermoplastic member can be effectively melted, the melted and contacted configuration can be pulled, and a plurality of components that are in contact with both sides are filled and integrated. can do it Here, by interposing the thermoplastic member between the first spring and the second spring, disconnection of the thermal fuse part can be accurately made at the temperature of the thermal fuse composite resistor where disconnection is required, and the molten first spring and the second spring are attracted and conductive The first spring and the second spring can be integrated with each other in a state of being spaced apart from the connection part and the first terminal cap, and thus the reliability of the thermal fuse composite resistor can be improved.

Although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and common knowledge in the field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims It will be understood by those having the above that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the technical protection scope of the present invention should be defined by the following claims.

100: temperature fuse composite resistor 110: winding resistance part
111: winding rod 112: wire
120: thermal fuse unit 121: body
122: thermoplastic member 122a: fusible part
122b: flux part 122c: melt of thermoplastic member
123: first spring 124: second spring
125: electrically conductive member 126: insulating member
130: conductive connection 140: first terminal cap
150: second terminal cap 160: outer protection part
161: case 162: insulating molding liquid

Claims (4)

a winding resistance unit having a winding rod extending in a first direction and a wire wound on an outer circumferential surface of the winding rod;
a thermal fuse unit connected to the winding resistance unit to block a current transmitted from the winding resistance unit at a predetermined temperature or higher;
a conductive connection part connecting the winding resistor part and the thermal fuse part in series; and
and a first terminal cap coupled to the end of the thermal fuse part in the first direction;
The thermal fuse unit,
an insulating body having an internal space penetrated in the first direction;
a thermoplastic member provided between the conductive connection part and the first terminal cap and at least partially melted at the predetermined temperature;
a first spring provided between the conductive connection part and the thermoplastic member to provide an elastic force to the thermoplastic member; and
a second spring providing an elastic force opposite to the first spring;
The thermal fuse composite resistor in which the conductive connection part and the first terminal cap are electrically separated by melting of the thermoplastic member. The method according to claim 1,
The thermoplastic member,
a fusible part comprising a metal that is melted at the predetermined temperature; and
and a flux part provided in contact with the fusible part;
The first spring and the second spring are provided on both sides of the thermoplastic member in contact with the fusible portion, respectively. 3. The method according to claim 2,
wherein the first spring and the second spring are coated with a metal material including a metal included in the fusible part. The method according to claim 1,
The temperature-fuse composite resistor in which the length of the change in the first direction of the first spring due to the melting of the thermoplastic member is smaller than the length of the thermoplastic member.

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