JPH0579915U - Surface mount inductor - Google Patents

Abstract

(57) [Summary] [Purpose] The height is low, the mounting area is small, the number of parts is small, and the reliability is high. [Structure] A drum core 17 having a winding wound inside a cylindrical core 11 is coaxially arranged, and both ends 19 of the winding are led out to the upper side. Grooves 12 reaching both end surfaces are formed on the outer surface on the opposite side of the tubular core 11, and plate terminals 14 are fitted into the grooves 12, and the lower end thereof is a mounting portion 14a and is bent to the end surface of the tubular core 11. Be contacted. A notch 13 is formed in the cylindrical core 11 at the upper end of the groove 12, and fixing pieces 14b and 14c which are cut open inward from the upper end of the terminal 14 are bent and inserted into the notch 13.
The terminal 14 is attached so that the core 11 is sandwiched between the fixing pieces 14b and 14c and the end portion 14a.
The winding terminal 19 is press-fitted and connected to the slit between b and 14c.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a surface-mount inductor which is configured by arranging a drum core in a cylindrical core and winding the drum core so as to be surface-mounted on a wiring board.

[0002]

[Prior Art]

 In this type of surface-mount inductor, it is required to make the components smaller and to lower the height.Therefore, it is necessary to extend the plate terminals in the lateral direction or deposit a silver electrode on the bottom surface of the core. Has been done. The former case has a drawback in that the mounting area is wide when the terminal is provided in the lateral direction, and it is usually necessary to attach a resin substrate for attaching the terminal, which causes a problem of increasing the number of parts. Furthermore, if the end of the winding is brought closer to the wiring board mounting part of the terminal, the wire becomes thin due to the solder at the terminal soldering part, or a solder alloy layer forms and becomes hard and brittle, and the wire breaks due to mechanical vibration. Easier to do. If this situation is avoided, the terminal structure will have a complicated shape, resulting in problems of high cost and low reliability. On the other hand, when the silver electrode is vapor-deposited, there is a problem that the cost is high and the electrode peels off due to the heat during soldering, resulting in poor reliability.

[0003]

[Means for Solving the Problems]

 According to this invention, a groove in the axial direction is formed on the outer surface of the cylindrical core, a notch is formed in the cylindrical core at one end of the groove, and a plate-shaped terminal is fitted in the groove. One end of the terminal is connected to the end of the winding lead out from the notch, and the other end surface is bent and contacted with the end surface of the tubular core.

[0004]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. For ease of understanding, an embodiment of this invention will be described in the order of assembling. The cylindrical core 11 made of a magnetic material is formed in a cylindrical shape in this example, and its length in the axial direction is relatively short. A groove 12 is formed on the outer surface of the tubular core 11 along the axial direction thereof. In this example, one groove 12 is formed on each side of the cylindrical core opposite to the diameter of the shaft center, and each groove 12 reaches both end surfaces of the cylindrical core 11. A notch 13 is formed in the tubular core 11 at one end of the groove 12, that is, at the upper end in the figure. The width of the notch 13 is substantially the same as the width of the groove 12.

A plate-shaped terminal 14 made of, for example, phosphor bronze is fitted into these grooves 12. In this case, the opposite wall surfaces of the groove 12 are used as inner tapered surfaces so that both ends of the terminal 14 are engaged with both side walls of the groove 12 from one end of the terminal groove 12 and the terminal 14 is vibrated along the groove to move to the groove 12. It is designed to fit. In this example, the lower ends of the terminals 14 are bent inwardly and are in contact with the end faces of the tubular core 11 to form the mounting parts 14a. The other end of the terminal 14, that is, the upper end, is provided with a slit 15 that extends downward from the center thereof, and the slit is extended to both sides in the width direction. The upper end of the terminal 14 is pushed open around the notch 15 to form the fixing pieces 14b and 14c. The fixing pieces 14b and 14c are pushed into the notches 13, and the fixing pieces 14b are placed on the core end surface 16 of the notches 13. , 14c are positioned, and the core 11 is sandwiched between the fixing pieces 14b, 14c and the mounting portion 14a. In this way, the terminal 14 is attached to the tubular core 11 as shown in FIG.

On the other hand, the winding 18 is provided on the drum core 17 made of a magnetic material, and both ends of the winding 18 are led out to the one end side of the drum core 17 as winding ends 19. The drum core 17 provided with the winding 18 is coaxially inserted into the tubular core 11. At that time, the drum core 17 is positioned on the end of the terminal mounting portion 14a to prevent the drum core 17 from coming off. As shown in FIG. 3, the winding terminal 19 is press-fitted into the slit between the fixing pieces 14b and 14c of the terminal 14 to connect the winding terminal 19 and the terminal 14. An adhesive is filled between the tubular core 11 and the drum core 17 as needed.

[0007]

[Effect of the device]

 As described above, according to the inductor of the present invention, the height thereof can be made substantially the same as the height of the drum core 17 and the tubular core 11, and the overall height can be reduced. Further, the terminal 14 can be easily manufactured by punching out from a hoop material, and can be manufactured at low cost as a whole. Further, with respect to the mounting portion 14a of the terminal 14, the connection portion between the winding terminal 19 and the terminal 14 is on the opposite side, which is unlikely to be broken even by mechanical vibration, and the terminal is mounted on the wiring board. It is not easily affected by heat when soldering. Furthermore, there is no need for a resin base for attaching the terminals, the number of parts is small, and there is no problem of vapor deposition separation of the silver electrode. The inspection at the time of soldering is easy because the solder of the mounting portion 14a can be seen, and the reworking work using a soldering iron can be performed with good workability, and the peeling and bending of the electrodes do not occur, so the reliability is high. It will be expensive.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state before assembly of a tubular core and a terminal.

FIG. 2 is a perspective view showing a cylindrical core having terminals attached thereto and a drum core having a winding.

FIG. 3 is a perspective view showing an assembled state of the embodiment according to the present invention.

Claims (1)

[Scope of utility model registration request] 1. A surface mount inductor in which a drum core made of a magnetic material is coaxially arranged in a cylindrical core made of a magnetic material, and a winding is provided on the drum core, wherein an axial center is provided on an outer surface of the cylindrical core. A groove along the direction is formed, a cutout is formed in the cylindrical core at one end of the groove, a plate-like terminal is fitted in the groove, and one end of the terminal is wound out from the cutout. A surface mount inductor, which is connected to an end of a wire, and the other end of the terminal is bent and contacted with an end face of the tubular core.