JP2006278663A - Surface mounting component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable surface mounting component wherein a mounting terminal of a mounting component is positioned after printing of molten solder on a mounting substrate, molten solder immediately under the mounting terminal can be ensured enough even if the mounting terminal is pressurized and mounted, and the mounting component is not likely to fall off from a circuit substrate even if vibration, impact or the like is applied. <P>SOLUTION: The surface mounting component consists of a transformer body 11 with a built-in core with a coil wound thereon, and a mounting terminal 12 led out to an outside from the transformer body 11 and electrically connected to the coil, and is subjected to surface mounting by performing reflow soldering for the mounting terminal 12 to a land 14 of a circuit substrate 13. A connection terminal piece 15 facing the land 14 of the circuit substrate 13 of the mounting terminal 12 is subjected to mountain fold, and a solder storage 16 for storing solder is provided to the lower surface of the connection terminal piece 15. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a surface mount component such as a transformer, a trigger coil, and a choke coil used in an optical device such as a camera or a small electronic device.

  Small transformers used in optical devices such as cameras and small electronic devices such as mobile phones are stored in a narrow space limited to optical devices and small electronic devices. Therefore, miniaturization and thinning are required. . In addition, it is desired that the mounting component is firmly soldered to the circuit board so that the mounting component does not fall off the circuit board even when vibration or impact is applied.

Therefore, in order to satisfy the above-described requirements, a surface mount type component such as a transformer or a trigger coil includes a winding frame portion and upper and lower flange portions extending at both ends of the winding frame portion. A coil body having a winding on a core winding frame, an external connection terminal having a solderable layer attached to the surface thereof, and a core mounting portion extending from the external connection terminal and wider than the external connection terminal And a lead frame provided with a solder adhesion preventing layer on the lower surface of the core mounting portion of the lead frame. (For example, refer to Patent Document 1).
Japanese Patent No. 3317893

  In the above-mentioned patent document 1, a core of molten solder is used when the electrode land of the circuit board and the external connection terminal of the surface mount coil are solder-connected by the solder adhesion preventing layer provided on the lower surface of the core mounting portion of the lead frame. Diffusion to the lower surface of the mounting portion is suppressed, and the molten solder stays on the electrode land so that a solder fillet is formed on the external connection terminal.

  The solder adhesion preventing layer is provided with a synthetic resin layer such as an epoxy resin or a fluororesin so that the solder is less likely to adhere than the lead frame material metal so that the molten solder stays on the electrode land.

  However, after the molten solder is printed on the electrode lands on the circuit board, the mounting terminals of the surface mount type coil are positioned and pressed to mount, but during mounting, the molten solder directly under the mounting terminals is pressed in the side direction. To be eliminated. Therefore, the amount of molten solder directly under the mounting terminal is insufficient, and when reflow is performed in this state, the solder connection with the mounting board is only the side connection, the bonding strength of the mounting terminal is low, vibration and impact, etc. When added, the surface mount coil may fall off the circuit board, and there is a problem of lack of reliability.

  The present invention has been made paying attention to the above circumstances, and the purpose thereof is to print the molten solder on the mounting board, position the mounting terminals of the mounting components, and pressurize and mount the mounting terminals. Another object of the present invention is to provide a highly reliable surface mounting component that can secure a sufficient amount of molten solder directly below the mounting terminal and that does not cause the mounting component to fall off the circuit board even when vibration or impact is applied.

  In order to solve the above-mentioned object, the present invention provides a component main body including a core around which a coil is wound, and a mounting terminal that is led out from the component main body and is electrically connected to the coil. In a surface-mounted surface-mounted component that is mounted by reflow soldering this mounting terminal to a circuit board land, the connection terminal piece facing the circuit board land of the mounting terminal is folded in a mountain, A solder retention portion for retaining solder is provided on the lower surface of the connection terminal piece.

  According to a second aspect of the present invention, a component main body including a core around which a coil is wound and a mounting terminal led out from the component main body and electrically connected to the coil are provided. In a surface-mounted surface-mounted component that is mounted by reflow soldering, a solder retaining portion comprising a plurality of recessed portions that retain solder on the lower surface of the connection terminal piece facing the land of the circuit board of the mounting terminal. It is provided.

  According to a third aspect of the present invention, there is provided a component main body including a core around which a coil is wound, and a mounting terminal led out from the component main body and electrically connected to the coil. In a surface-mounted surface-mounted component that is mounted by reflow soldering, a solder retention portion that retains solder by forming a lower surface of a connection terminal piece facing the land of the circuit board of the mounting terminal in a sawtooth shape It is provided.

  According to the present invention, by providing a solder retention portion that retains solder on the lower surface of the connection terminal piece, it is possible to sufficiently secure the molten solder directly below the mounting terminal, and the mounting component can be removed from the circuit board even if vibration or impact is applied. There is an effect that reliability can be improved without fear of dropping off.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 3 show a first embodiment, FIG. 1 (a) is a perspective view seen from the upper side of a transformer as a surface mount component, (b) is a perspective view seen from the lower side of the transformer, FIG. Is a side view of the mounting state, and FIG. 3 is an enlarged side view of the mounting terminal. As shown in FIGS. 1 to 3, a transformer main body 11 as a component main body including a core around which a coil is wound is formed of an epoxy resin or the like. A plurality of mounting terminals 12 made of a metal material are provided at both ends of the transformer body 11.

  The mounting terminals 12 are formed in a substantially L-shaped portion protruding (exposed) from the transformer main body 11 and are attached along the side surface 11 a to the lower surface 11 b of the transformer main body 11. That is, the mounting terminal 12 has a connection terminal piece 15 facing the land 14 of the circuit board 13, and the connection terminal piece 15 is folded into a substantially U shape and soldered to the lower surface of the connection terminal piece 15. A solder retention portion 16 is provided for retention. The solder staying portion 16 has a certain degree of rigidity. Even when the connection terminal piece 15 is pressed from above during mounting, the solder staying portion 16 directly below the connection terminal piece 15 is not crushed and the amount of the molten solder 17 is reduced. Can be secured sufficiently. Therefore, unlike the conventional case, the molten solder just below the connection terminal piece is not eliminated in the lateral direction. When the transformer body 11 is reflow soldered to the land 14 of the circuit board 13, sufficient molten solder 17 is provided. It can be implemented with a certain amount.

  FIG. 4 is an enlarged side view of the mounting terminal according to the second embodiment. As shown in FIG. 4, a plurality of mounting terminals 12 are provided at both ends of the transformer main body 11. These mounting terminals 12 are formed in a substantially L-shaped portion projecting from the transformer main body 11, and are attached along the lower surface 11 b from the side surface 11 a of the transformer main body 11. Further, the connection terminal piece 18 of the mounting terminal 12 is flat, and a solder retention portion 19 is provided on the lower surface of the connection terminal piece 18, which is an uneven portion, that is, a plurality of recesses for retaining solder.

  According to the present embodiment, even when the connection terminal piece 18 is pressurized from above at the time of mounting, the solder retaining portion 19 directly below the connection terminal piece 18 is not crushed, and a sufficient amount of the molten solder 17 can be secured. Therefore, unlike the conventional case, the molten solder just below the connection terminal piece is not eliminated in the lateral direction. When the transformer body 11 is reflow soldered to the land 14 of the circuit board 13, sufficient molten solder 17 is provided. It can be implemented with a certain amount.

  FIG. 5 shows the third embodiment and is an enlarged side view of a mounting terminal. As shown in FIG. 4, a plurality of mounting terminals 12 are provided at both ends of the transformer main body 11. These mounting terminals 12 are formed in a substantially L-shaped portion projecting from the transformer main body 11, and are attached along the lower surface 11 b from the side surface 11 a of the transformer main body 11. Further, the connection terminal piece 20 of the mounting terminal 12 is flat, and a solder retaining portion 21 having a sawtooth shape, that is, a plurality of concave grooves for retaining solder is provided on the lower surface of the connection terminal piece 20.

  According to the present embodiment, even when the connection terminal piece 20 is pressed from above at the time of mounting, the solder staying portion 21 directly below the connection terminal piece 20 is not crushed, and a sufficient amount of the molten solder 17 can be secured. Therefore, unlike the conventional case, the molten solder just below the connection terminal piece is not eliminated in the lateral direction. When the transformer body 11 is reflow soldered to the land 14 of the circuit board 13, sufficient molten solder 17 is provided. It can be implemented with a certain amount.

  Therefore, according to the present invention, by providing a solder retention portion that retains solder on the lower surface of the connection terminal piece, a sufficient amount of molten solder just below the mounting terminal can be secured, and the mounted component can be circuitized even if vibration or impact is applied. There is an effect that reliability can be improved without fear of falling off the substrate.

  In addition, according to each said embodiment, although the case of the transformer as a surface mounting component was demonstrated, it is applicable to surface mounting components, such as a trigger coil and a choke coil.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The 1st Embodiment of this invention is shown, (a) is the perspective view seen from the upper side of the trans | transformer as surface mount components, (b) is the perspective view seen from the lower side of the transformer. The side view of the mounting state of a transformer. The side view which expanded the mounting terminal of the embodiment. The side view which expanded the mounting terminal of the transformer which shows the 2nd Embodiment of this invention. The side view which expanded the mounting terminal of the transformer which shows the 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Transformer main body (surface mount component), 12 ... Mounting terminal, 13 ... Circuit board, 14 ... Land, 15, 18, 20 ... Connection terminal piece, 16, 19, 21 ... Solder retention part, 17 ... Molten solder

Claims (3)

It consists of a component main body with a built-in core around which a coil is wound, and a mounting terminal that is led out from the component main body and is electrically connected to the coil. The mounting terminal is reflow soldered to the land of the circuit board. In surface-mounted parts to be mounted
A surface-mount component comprising: a mounting portion that folds a connection terminal piece facing a land of the circuit board of the mounting terminal; and a solder retention portion that retains solder on a lower surface of the connection terminal piece. It consists of a component main body with a built-in core around which a coil is wound, and a mounting terminal that is led out from the component main body and is electrically connected to the coil. The mounting terminal is reflow soldered to the land of the circuit board. In surface-mounted parts to be mounted
A surface-mounted component comprising a solder retaining portion including a plurality of recessed portions for retaining solder on a lower surface of a connection terminal piece facing a land of the circuit board of the mounting terminal. It consists of a component main body with a built-in core around which a coil is wound, and a mounting terminal that is led out from the component main body and is electrically connected to the coil. The mounting terminal is reflow soldered to the land of the circuit board. In surface-mounted parts to be mounted
A surface-mounted component comprising a solder retention portion for retaining solder by forming a lower surface of a connection terminal piece facing the land of the circuit board of the mounting terminal in a sawtooth shape.

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