TW201805985A - Fuse resistor and method of manufacturing the same - Google Patents

Abstract

Disclosed are a fuse resistor and a method of manufacturing the same, more particularly, are a fuse resistor mounted at an electric circuit of an electronic product to prevent the electronic product from breaking down due to inrush current, increase of internal temperature, and continuous overcurrent, and a method of manufacturing the same. The fuse resistor is capable of simplifying an assembly process by coupling a thermal fuse and a lead wire in a modularized manner and by fixing a fusing lead wire to the lead wire in an integrated manner to form a lower molding unit, and a method of manufacturing the same. The fuse resistor has a simple structure and is capable of being miniaturized as an integrated structure of the thermal fuse and the lead wire is inserted, and a method of manufacturing the same.

Description

Fuse resistor and method of manufacturing same

The present invention relates to a fuse resistor and a method of manufacturing the same, and more particularly to a fuse resistor mounted on a circuit of an electronic product to prevent an electronic product from being caused by surge current, internal temperature rise, and continuous overcurrent. Damage and the method of making the fuse resistor.

Generally, in circuits of large electronic products, such as LCD televisions or plasma televisions, a protector is provided at the input, such as a thermal fuse resistor for protecting the circuit. Therefore, the protector prevents damage of the electronic product due to the surge current generated by the power supply, the rise of the internal temperature, and the continuous overcurrent.

The fuse resistor includes a resistor, a thermal fuse, and a lead connecting the resistor to the thermal fuse.

In addition, when the fuse is blown, a fragment occurs in the fuse resistor. In order to prevent the fragment from affecting other electronic components, the resistor and the thermal fuse are packaged by a housing, and the housing is filled with a filler.

Here, a slurry type filler containing cerium oxide (SiO ₂ ) is used for the filler in consideration of heat resistance, electrical conductivity, and hardening. Typically, a housing formed of a ceramic material is used for the housing. The ceramic housing is used for a general resistive housing.

Furthermore, the ends of the leads extend to be withdrawn from the outside of the housing. In a conventional fuse resistor, the end of the lead is soldered to a printed circuit board such that the resistor and the thermal fuse are mounted vertically on the printed circuit board.

Therefore, in the case where a surge current is introduced, such a fuse resistor, as described above, uses the resistor to limit the surge current at a certain current value. In the case where an overcurrent is introduced, the heat generated by the heating of the resistor is transferred to the thermal fuse through the filler, and then the solid lead or fuse formed by the polymer particles is melted in the thermal fuse to generate A short circuit. Therefore, the circuit of the electronic product is protected.

6A and 6B show a conventional fuse resistor. Referring to FIGS. 6A and 6B, Korean Patent No. 10-1060013 discloses a fuse resistor including a resistor 10, a thermal fuse 20, leads 31 and 33, a housing 40 and a filler 50. Due to thermal effects, the thermal fuse 20 is configured to create a short circuit. Leads 31 and 33 connect the resistor 10 in series with the thermal fuse 20. The housing 40 has an open side for receiving the resistor 10 and the thermal fuse, and extends from the slot 41 by a groove 41 formed in a wall of the housing 40 and ends of the leads 31 and 33. The filler 50 fills the inner space of the casing 40 to embed the resistor 10 and the thermal fuse 20 in the filler 50 formed of cerium oxide.

It is difficult to miniaturize the fuse resistor 10 described in Korean Patent No. 10-1060013. Further, since a pair of leads 31 and 32 and a pair of leads 33 and 34 are respectively connected to the resistor 10 and the thermal fuse 20, the process of manufacturing the fuse resistor is complicated, and then, the lead of the resistor 10 is 31 and the leads 33 of the thermal fuse 20 are connected to each other.

Accordingly, the present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide a thermal fuse and a method of manufacturing the same by coupling a thermal fuse in a modular manner with A lead, and by securing a fuse lead to the lead in an integrated manner, simplifies the assembly process to form the lower molding unit.

Another object of the present invention is to provide a fuse resistor having a simple structure and capable of miniaturizing the fuse resistor when the thermal fuse and the integrated structure of the lead are embedded.

According to the present invention, in order to achieve the above and other objects, the present invention provides a fuse resistor comprising: a resistor; a fuse lead including a first line portion, a second line portion, and a thermal fuse The first wire portion is coupled to one end of the resistor, the second wire portion is connected to a substrate, one end of the thermal fuse is coupled to the first wire portion, and the other end of the thermal fuse is coupled Connected to the second line portion; a lead is connected to the other end of the resistor; the lower molding unit is injection molded in a state in which a part of the fuse lead and a part of the lead are spaced apart from each other And an upper housing having a cylindrical shape, one side of the upper housing being provided with an opening, the upper housing receiving the resistor, a portion of the fuse lead and a portion of the lead, and the opening The lower molding unit is coupled.

The upper casing may be filled with a filler which may be formed of cement, and the lower molding unit may be formed of a resin having a lower thermal conductivity than the filler.

The lower molding unit may be formed to have a thickness to accommodate a portion of the first line portion, a portion of the second line portion, and the thermal fuse.

The distance from the horizontal centerline of the resistor to the upper surface of the lower molding unit may be less than the distance from the horizontal centerline of the resistor to the upper surface of the thermal fuse.

The distance from the horizontal centerline of the resistor to the upper surface of the lower molding unit may be greater than the distance from the horizontal centerline of the resistor to the lower surface of the thermal fuse.

The lower molding unit may be provided with a portion on its edge portion, and the seat portion may have a width corresponding to the thickness of the upper housing.

The resistor may include a wire wound resistor including a ceramic rod, a pair of terminals disposed at two ends of the ceramic rod, and a wire wound around the ceramic rod, and a crucible may be coated on the ceramic rod and The surface of the line is formed to form a coating layer.

To achieve the above and other objects, the present invention provides a method of manufacturing a fuse resistor, comprising: preparing a fuse lead and a lead; coupling two ends of a resistor to the fuse lead and the lead; forming a a molding unit, wherein the lower molding unit is injection molded, wherein a portion of the fuse lead and a portion of the lead are embedded in the lower molding unit and spaced apart from each other; a filler is passed through an opening Filling an inner space of the upper casing, wherein the upper casing is cylindrical and provided with the opening on one side thereof; and the resistor embedded in the upper casing, coupling the upper casing to the lower portion Molding unit.

The fuse lead may include a first line portion, a second line portion and a thermal fuse, the first line portion being coupled to one end of the resistor, the second line portion being coupled to a substrate, the heat fuse One end of the device can be coupled to the first line portion, the other end of the thermal fuse can be coupled to the second line portion, and the first line portion, the second line portion, and the thermal fuse can have the same diameter .

In order to fully understand the objects, features and advantages of the present invention, the present invention will be described in detail by the following specific embodiments and the accompanying drawings.

Referring to Figures 1A, 1B, 2A, 2B, 2C, 2D and 3, in accordance with the present invention, a fuse resistor having the component number "100" can be placed on a circuit for an electronic product. The fuse resistor 100 can include a resistor 110, a fuse lead 120 coupled to each end of the resistor 110, and a lead 130. The lower molding unit 140 is formed in an embedded manner in an embedded state. A portion of the fuse lead and a portion of the lead are spaced apart from each other, coupled to an upper housing 150 of the lower molding unit 140, and a filler 160 filling the interior of the upper housing 150.

When an overcurrent is applied, the resistor 110 radiates heat so that the thermal fuse 125 mounted on the fuse lead 120 can be blown. As shown in FIG. 2B, for example, the resistor 110 is a wire wound resistor comprising a ceramic rod 111, a terminal 117 disposed at both ends of the ceramic rod 111, and a wire 113 wound around the ceramic rod 111.

Further, as shown in FIG. 2B, a coating layer 115 may be formed on the surface of the resistor 110, or as shown in FIGS. 2C and 2D, a filling layer 115' or 115" may be formed on the surface of the resistor 110. on.

The coating 115 has the function of protecting the wire 113 and improving explosion protection. As shown in FIG. 2B, the coating layer 115 can be formed by thinly coating the ceramic rod 111 and the surface of the wire 113.

The filling layer 115' or 115" has a function of maximizing the explosion-proof protection of the resistor 110. As shown in Figures 2C and 2D, the filling layer 115' or 115" can be filled between the pair of terminals 117 by using a crucible. Space. In any event, the thickness of the fill layer 115' or 115" may be equal to the thickness of the terminals 117. Therefore, the line 113 may be completely sealed.

In the case where an abnormal current is applied and the resistor 110 is exploded, the coating 115 or the filling layer 115' or 115" may initially absorb shock and noise due to the explosion. Therefore, the explosion-proof protection of the product is improved.

The fuse lead 120 and the lead 130 are coupled to the respective terminals 117 of the resistor 110.

The fuse lead 120 includes a first line portion 121, a second line portion 123, and a thermal fuse 125. The first line portion 121 is coupled to the resistor and bent downward. The second line portion 123 is connected. To a substrate. In this case, one end of the thermal fuse 125 is coupled to the first line portion 121, and the other end of the thermal fuse 125 is coupled to the second line portion 123.

As described above, the thermal fuse 125 is embedded between the first line portion 121 and the second line portion 123 of the fuse lead 120. Thus, it is feasible to simplify and miniaturize the structure.

The thermal fuse 125 is blown due to heat radiation from the resistor 110 to create a short circuit. Therefore, the thermal fuse 125 has the function of protecting the device mounted on the circuit.

Further, as shown in FIG. 3, the thermal fuse may include a fusible portion 126 and a bent portion 127 embedded in a central portion of the fusible portion 126. For example, the fusible portion 126 may comprise tin nitride (TiN) or a tin nitride alloy. When heated, the fusible portion 126 is fused to block electrical connections.

The bent portion 127 has a function of agglomerating the melted fusible portion 126. For example, the bent portion 127 may contain chloride, fluoride, resin, or the like.

When the thermal fuse 125 and the first wire portion 121 and the second wire portion 123 are coupled, an end of the fusible portion 126 formed of a metal material contacts each end of the first wire portion 121 and the second wire portion 123. And then perform the welding. In this case, the diameter of the thermal fuse 125 may be the same as the diameter of the first line portion 121 and the second line portion 123. When the diameter of the thermal fuse 125 is larger than the diameters of the first line portion 121 and the second line portion 123, at least the diameter of the bent portion 127 is smaller than the diameters of the first line portion 121 and the second line portion 123. Therefore, the fusible portion 126 should be in contact with the first line portion 121 and the second line portion 123.

In the thermal fuse 125, if the fusible portion is formed to be embedded in a central portion of the flexure portion, and the heat supplied by the resistor heats the flexure portion and then heats the fusible portion, the time of the fuse is The characteristics that are delayed and blown are reduced. Further, when the buckling portion formed of a dielectric material is mounted on the thermal fuse, the buckling portion cannot be coupled using a spot welding process. Therefore, the thermal fuse 125 may preferably have a structure in which the bent portion 127 is embedded in the fusible portion 126.

The upper housing 150 may include any one of a thermosetting resin, a thermoplastic resin, and a ceramic material. The upper housing 150 is cylindrical and has an opening 151 provided on one side. The resistor 110 and a portion of the fuse lead 120 and the lead 130 are embedded in the upper housing 150 through the opening 151.

The opening 151 of the upper housing 150 is sealed by the lower molding unit 140. A filler 160 provided with explosion-proof protection fills the inner space of the upper casing 150.

When the resistor 110 is exploded, the filler 160 absorbs shock and noise. For example, the filler 160 may comprise cement, tantalum, and a resin, such as an epoxy resin.

As shown in FIG. 2A, the lower molding unit 140 is injection molded to accommodate the port between the thermal fuse 125 and the first wire portion 121 and the second wire portion 123. In this case, the lower molding unit 140 seals the two ports of the thermal fuse 125. Therefore, damage to the thermal fuse 125 or separation of the first wire portion 121 and the second wire portion 123 can be prevented during assembly.

In addition, the resistor 110, the fuse lead 120 and the lead 130 are modularized by the lower molding unit in an integrated manner, so that the lower molding unit 140 can be easily coupled to the upper housing 150. In addition, the fuse lead 120 and the lead 130 are spaced apart from each other such that the defective product can be reduced during surface mounting of the fuse resistor.

The lower molding unit 140 is formed in a block shape or a plate shape having a size corresponding to the opening 151 of the upper casing 150 to seal the opening 151. A portion 141 is disposed at an edge region of the upper surface of the lower molding unit 140 to have a width corresponding to the thickness of the upper casing 150. In this case, the lower molding unit 140 is coupled to the upper housing 150 in an engaged manner.

In addition, as shown in FIG. 4, the lower molding unit 140' may be injection molded such that the thermal fuse 125 is not embedded in the lower molding unit 140', and only one end of the second wire portion 123 is embedded in the lower mold. Unit 140'.

Hereinafter, the filler 160 is formed of cement and the lower molding unit 140 is formed of a resin, and the fusing characteristics of the lower molding unit 140 of Fig. 2A and the lower molding unit 140' of Fig. 4 are compared.

In the lower molding unit 140 of FIG. 2A, the distance d1 from the horizontal center line c of the resistor 110 to the upper surface of the lower molding unit 140 is smaller than the horizontal center line c from the resistor 110 to the thermal fuse 125. The surface distance is d2.

In the lower molding unit 140' of FIG. 4, the distance d1' from the horizontal center line c of the resistor 110 to the upper surface of the lower molding unit 140 is greater than the horizontal center line c from the resistor 110 to the thermal fuse 125. The lower surface distance is d3.

The fusing characteristics of the lower molding units 140 and 140' will be given. In FIG. 4, the space between the lower molding unit 140' and the resistor 110 is larger than the space between the lower molding unit 140' and the resistor 110 in FIG. In this case, the heat of the resistor 110 is absorbed and radiated outward to the filler 160, so that the heat transferred to the thermal fuse 125 is relatively lowered.

However, in FIG. 2A, the thermal fuse 125 is completely embedded in the lower molding unit 140, which has a lower thermal conductivity than the filler 160, and between the lower molding unit 140 and the resistor 110 The space is relatively narrow. Therefore, in contrast to FIG. 4, the conduction heat system transmitted from the resistor 110 to the thermal fuse 125 through the first line portion 121 in FIG. 2A is increased. Therefore, according to the above, the fuse characteristics are improved.

Hereinafter, a method of manufacturing a fuse resistor will be described with reference to the drawings.

First, referring to FIG. 5A, the first line portion 121, the second line portion 123, the fuse lead 120 coupled to the second line portion 123, and the lead 130 are prepared.

The thermal fuse 125 is coupled to the first line portion 121 and the second line portion 123 by a soldering process, a spot welding process, or an ultrasonic welding process.

Next, referring to FIG. 5B , after the two ends of the resistor 110 are respectively coupled to the fuse lead 120 and the lead 130 , the fuse lead 120 and the lead 130 are bent.

Then, referring to FIG. 5C, the fuse lead 120 and the lead 130 are insert-molded to form the lower molding unit 140. Here, the lower molding unit 140 is emitted to receive the thermal fuse 125 and a portion of the second wire portion 123 of the fuse lead 120.

Next, referring to FIG. 5D, an upper casing 150 having a cylindrical shape and having an opening 151 on one side is prepared. The upper housing 150 is provided with an upwardly facing opening 151. The filler 160 fills the inner space of the upper housing 150. The resistor 110 modularized by the lower molding unit 140 is embedded in the upper housing 150, and the lower molding unit 140 is coupled to the upper housing 150. Thereby the fabrication of the fuse resistor is completed.

Finally, in accordance with the present invention, the thermal fuse 125 is embedded in the fuse lead 120 to form a simple structure, and as such, miniaturization of the product can be achieved. The fuse lead 120 and the lead 130 are fixed in an integrated manner to form the lower molding unit 140. In this case, the lower molding unit 140 is coupled to the upper housing 150, and as such, the manufacturing process can be simplified.

As is apparent from the above description, in accordance with the present invention, the thermal fuse and the leads are coupled to form a module, and the fuse leads and leads are fixed in an integrated manner to form the lower molding unit. Therefore, the assembly process can be simplified.

Further, according to an embodiment of the present invention, the thermal fuse and the lead are formed into an embedded structure in an integrated manner, and as such, the structure is simple and miniaturized.

Although the exemplary embodiments of the present invention have been disclosed for the purposes of illustration, it will be understood by those skilled in the art It is possible. Therefore, the scope of the invention should not be limited or limited by the embodiments described herein, and should be construed as including the scope of the claims

10‧‧‧Resistors
20‧‧‧ Thermal fuse
31~34‧‧‧Leader
40‧‧‧shell
41‧‧‧ slots
50‧‧‧Filling
100‧‧‧Fuse resistor
110‧‧‧Resistors
111‧‧‧Ceramic rod
113‧‧‧ line
115‧‧‧ Coating
115'‧‧‧ fill layer
115"‧‧‧ fill layer
117‧‧‧terminal
120‧‧‧Fuse leads
121‧‧‧First line
123‧‧‧Second Line
125‧‧‧ Thermal fuse
126‧‧‧Fuse Department
127‧‧‧Flexing Department
130‧‧‧Leader
140‧‧‧Lower molding unit
140'‧‧‧Lower molding unit
141‧‧‧
150‧‧‧Upper casing
151‧‧‧ openings
160‧‧‧Filling
C‧‧‧ horizontal central line
D1, d1'‧‧‧ distance
D2, d3‧‧‧ distance
SW‧‧‧Spot welder (Spot welder)

1A is a perspective view of a fuse resistor in accordance with an embodiment of the present invention. 1B is an exploded perspective view of a fuse resistor in accordance with an embodiment of the present invention. FIG. 2A is a cross-sectional view of FIG. 1. FIG. Fig. 2B is a cross-sectional view showing a coating on a resistor in accordance with the present invention. 2C is a cross-sectional view showing a filling layer on a resistor in accordance with the present invention. 2D is a cross-sectional view showing a filling layer on a resistor different from FIG. 2C in accordance with the present invention. Fig. 3 is a perspective view of a thermal fuse according to the present invention. Fig. 4 is a cross-sectional view showing a fuse resistor having a lower molding unit different from the structure of Fig. 2A. Fig. 5A is a view showing the formation of a fuse lead according to the present invention. [Fig. 5B] A view showing a coupling lead to a resistor according to the present invention. [Fig. 5C] A view of a lower molding unit formed by injection of a fuse lead and an insert of a lead according to the present invention. [Fig. 5D] A view coupling the upper casing to the lower molding unit. [Fig. 6A, Fig. 6B] is a view of a conventional fuse resistor.

110‧‧‧Resistors

117‧‧‧terminal

123‧‧‧Second Line

130‧‧‧Leader

140‧‧‧Lower molding unit

141‧‧‧

150‧‧‧Upper casing

151‧‧‧ openings

Claims (9)

A fuse resistor comprising: a resistor; a fuse lead comprising a first line portion, a second line portion and a thermal fuse, the first line portion being coupled to one end of the resistor, the first The second wire is connected to a substrate, one end of the thermal fuse is coupled to the first wire portion, and the other end of the thermal fuse is coupled to the second wire portion; a lead wire is connected to the resistor One end; a lower molding unit that is injection molded in a state in which a portion of the fuse lead and a portion of the lead are spaced apart from each other; and an upper housing having a cylindrical shape, the upper housing An opening is disposed on one side of the body, and the upper housing houses the resistor, a portion of the fuse lead and a portion of the lead, and the opening is coupled to the lower molding unit. A fuse resistor according to claim 1, wherein: the upper casing is filled with a filler, the filler is formed of cement, and the lower molding unit is formed of a resin having a lower thermal conductivity than the filler. The fuse resistor of claim 1, wherein the lower molding unit is formed to have a thickness to accommodate a portion of the first line portion, a portion of the second line portion, and the thermal fuse. A fuse resistor according to claim 1, wherein a distance from a horizontal center line of the resistor to an upper surface of the lower molding unit is smaller than a distance from a horizontal center line of the resistor to an upper surface of the thermal fuse . The fuse resistor of claim 1, the distance from the horizontal center line of the resistor to the upper surface of the lower molding unit is greater than the distance from the horizontal center line of the resistor to the lower surface of the thermal fuse. A fuse resistor according to claim 1, wherein the lower molding unit is provided with a portion on an edge portion thereof, and the seat portion has a width corresponding to a thickness of the upper casing. The fuse resistor of claim 1, wherein: the resistor comprises a wire wound resistor, the wire wound resistor comprising a ceramic rod, a pair of terminals disposed at two ends of the ceramic rod, and a wound around the ceramic rod A line, and a tether is coated on the surface of the ceramic rod and the wire to form a coating layer. A method of manufacturing a fuse resistor, comprising: preparing a fuse lead and a lead; respectively coupling two ends of a resistor to the fuse lead and the lead; forming a lower molding unit, wherein the lower molding unit is Insert injection molding, wherein a portion of the fuse lead and a portion of the lead are embedded in the lower molding unit and spaced apart from each other; a filler is filled into an inner space of the upper housing through an opening, wherein the upper portion The housing is cylindrical and is provided with one opening on one side thereof; and the resistor embedded in the upper housing is coupled to the lower molding unit. The method of manufacturing a fuse resistor according to claim 8, wherein: the fuse lead comprises a first line portion, a second line portion and a thermal fuse, the first line portion being coupled to the resistor One end of the second fuse is coupled to a substrate, one end of the thermal fuse is coupled to the first line portion, the other end of the thermal fuse is coupled to the second line portion, and the first line portion The second wire portion and the thermal fuse have the same diameter.