THERMAL FUSE RESISTOR, MANUFACTURING METHOD THEREOF, AND INSTALLATION METHOD THEREOF

• US 20120032774A1
• Filed: 04/21/2010
• Published: 02/09/2012
• Est. Priority Date: 04/21/2009
• Status: Active Grant

• Current Assignee: Smart Electronics, Inc.
• Original Assignee: Smart Electronics, Inc.
• Inventors: Jung, Jong Il, Kang, Doo Won, Ahn, Gyu Jin, Kim, Sung Kwang, Lee, Kyung Mi
• Granted Patent: US 8,400,253 B2
• Time in Patent Office: Days
• US Class Current: 337/414
• CPC Class Codes: H01H 2085/0412 specially adapted for being mounted on a printed circuit board
• CPC Class Codes: H01H 69/02 Manufacture of fuses
• CPC Class Codes: H01H 85/048 Fuse resistors
• CPC Class Codes: H01H 85/165 Casings
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

Disclosed are a thermal fuse resistor having a case injection-molded by using thermosetting resin having heat resistance less than that of filler, a manufacturing method of the thermal fuse resistor, and a method of installing the thermal fuse resistor such that a resistor and a thermal fuse are laid down on a printed circuit board. In the thermal fuse resistor, even if the case has a lighter weight and a thinner thickness by changing the material of the case as compared with those of a case according to the related art, the case is not easily broken, so that the case is suitable for the lightness and slimness of an electronic appliance employing the thermal fuse resistor. Since only the thickness of the case of the thermal fuse resistor is reflected to the thickness of the electronic appliance employing the thermal fuse resistor, the thermal fuse resistor is suitable for the slimness of the electronic appliance.

Claims

1. A thermal fuse resistor comprising:

a resistor;

a thermal fuse disconnecting a circuit as heat is applied thereto from the resistor;

a lead wire connecting the resistor with the thermal fuse in series;

a case provided with an open surface used to receive the resistor and the thermal fuse therein in a state in which an end of the lead wire is drawn out of the case and provided at one wall surface thereof with a drawing groove used to draw the lead wire; and

a filler filled in the case to bury the resistor and the thermal fuse therein and including silicon dioxide,

wherein the case is formed by injection-molding thermosetting resin having heat resistance less than heat resistance of the filler.

2. The fuse resistor of claim 1, wherein the resistor and the thermal fuse are provided in the case such that the resistor and the thermal fuse face the open surface side by side, and a wall surface of the case facing the open surface has a thickness in a range of about 0.5 mm to about 1.5 mm.

3. A manufacturing method of a thermal fuse resistor, the manufacturing method comprising:

connecting a resistor and a thermal fuse to each other in series by using a lead wire;

injection-molding a case to receive the resistor and the thermal fuse therein by using thermosetting resin;

inserting the resistor and the thermal fuse into the case while drawing an end of the lead wire out of the case;

filling the case, in which the resistor and the thermal fuse have been received, with a filler including silicon dioxide and having a form of slurry; and

drying the filler.

4. An installation method of a thermal fuse resistor including a resistor, a thermal fuse disconnecting a circuit as heat is applied thereto from the resistor, a lead wire connecting the resistor with the thermal fuse in series, a case including thermosetting resin, an open surface used to receive the resistor and the thermal fuse therein in a state in which an end of the lead wire is drawn out of the case, a drawing groove used to draw the lead wire at one wall surface of the case, and a filler filled in the case to receive the resistor and the thermal fuse therein, the installation method comprising:

soldering the lead wire drawn out of the case onto a printed circuit board; and

bending a lead wire provided between the case and the printed circuit board to allow the open surface of the case to face the printed circuit board, so that the resistor and the thermal fuse are laid down on the printed circuit board.