JP4648156B2 - Strobe booster unit and manufacturing method thereof - Google Patents

Description

  The present invention relates to a strobe booster unit built in a portable electronic device such as a digital camera and a method for manufacturing the same.

  A strobe unit in a digital camera uses a xenon lamp as a light emitting unit, and electronic components such as a step-up transformer, a step-up control IC, and a low-pass filter are mounted on a printed board as a strobe step-up unit for causing the xenon lamp to emit light.

  Digital cameras are required to be smaller and lighter, and the strobe booster unit incorporated in the camera body is also required to have a reduced area and a reduced thickness. Of the electronic components mounted on the printed circuit board, the step-up transformer is large in both area and thickness, making it difficult to reduce the size of the strobe booster unit. Although it is possible to reduce the size of the step-up transformer, it affects the performance of emitting xenon lamps, and there is a limit to downsizing.

  Therefore, a cut and an opening are formed in the printed board, and the three legs of the E-type magnetic core constituting the transformer are fitted into the cut and the opening from the back side to the front side of the printed board. Then, the E-type magnetic core and the I-type magnetic core are combined by contacting the I-type magnetic core on the three leg portions of the E-type magnetic core protruding to the surface side of the printed circuit board. Furthermore, it is known that the E-type magnetic core and the I-type magnetic core are fixed by hairpin-shaped fasteners to reduce the area of the mounting board, and the entire mounting board is miniaturized (for example, Patent Document 1). reference.).

Further, as shown in FIG. 7, in the conventional strobe booster unit, the booster transformer a is treated as an independent component, and the booster transformer a assembled in a separate process is mounted on the printed circuit board b by a mounting device or manually. Yes. Therefore, a soldering terminal d for connecting the lead wire of the coil c of the step-up transformer a to the printed circuit board b is required, and the soldering terminal d is generally made by press-fitting or insert molding. Note that electronic components f such as a boost control IC and a low-pass filter are mounted on the printed circuit board b.
Japanese Patent Laid-Open No. 11-40425

  Patent Document 1 described above has a structure in which a printed circuit board is combined from above and below with an E-type magnetic core and an I-type magnetic core, and is sandwiched between fasteners, so that the area of the mounting board can be reduced. The I-type magnetic core protrudes in the vertical direction of the printed circuit board. In addition, the legs of the E-type magnetic core are fitted into the notches and openings from the back side to the front side of the printed circuit board, and the I-type magnetic core is placed on the three legs of the E-type magnetic core protruding to the front side of the printed circuit board. There is a situation in which the E-type magnetic core and the I-type magnetic core are combined so that the assembling workability is poor.

Also, a step-up transformer assembled in a separate process and mounted on a printed circuit board by a mounting device or a manual work requires a manufacturing cost because it provides a soldering terminal for connecting the lead wire of the coil of the step-up transformer to the printed circuit board, This increases the cost of the strobe booster unit.
The present invention has been made paying attention to the above circumstances, and the object of the present invention is to easily mount the strobe step-up transformer on the printed circuit board, and to solder the lead wires of the coil of the strobe step-up transformer to the printed circuit board. It is an object of the present invention to provide a strobe booster unit that does not require a terminal and can reduce costs, and a method for manufacturing the same.

In order to solve the above-mentioned object, the invention according to claim 1 is a strobe booster unit in which various electronic parts such as a strobe booster transformer and a booster control IC are mounted on a printed circuit board, and the strobe booster transformer is mounted on the printed circuit board. Positioning one end portion of the central core to be configured, and arranging the central shaft portion of the central core projecting outward from the edge portion of the printed circuit board, leaving the portion of the conductive pattern of the printed circuit board, the printed circuit board, The various electronic components mounted on the printed circuit board and the central shaft portion of the central core are sealed with a resin layer over the printed circuit board, the various electronic components and the central shaft portion, and the resin layer is attached to the printed circuit board. wherein said central winding bobbin at the portion of the central shaft portion of the core is fixed to one end of the central core is formed, further wherein Forming a coil layer by winding a coil wire bobbin, with connecting leads of the coil layer to the conductive portion exposed to the outside, adjust the gap on both sides of a central core in which the coil layer is formed The side core is fixed.

Claim 2 is a method of manufacturing a strobe boost unit in which various electronic components such as a strobe boost transformer and a boost control IC are mounted on a printed circuit board.
Inside the mold, one end of the central core constituting the strobe step-up transformer is positioned on the printed circuit board, and the central shaft of the central core is temporarily fixed to protrude outward from the edge of the printed circuit board. Process,
The mold is filled with molten resin, and at least the conductive portion of the printed board is removed, and the printed board, the various electronic components mounted on the printed board, and the central shaft portion of the central core are sealed with a resin layer. A sealing step of stopping and fixing one end of the central core to the printed circuit board and forming a bobbin for winding;
The printed board including the central core sealed from the mold is taken out, a coil is wound around the bobbin for winding to form a coil layer, and the lead wire of the coil layer is connected to the conductive material of the printed board. Winding process to connect to the part,
A gap adjusting step of fixing the side core while adjusting the gap on both sides of the central core on which the coil layer is formed;
It is characterized by comprising.

  According to the present invention, the printed circuit board and the stroboscopic step-up transformer are integrated, and winding to the bobbin for winding is easy, and the stroboscopic step-up transformer does not require a soldering terminal for connecting the coil lead wire to the printed circuit board. Thus, the cost can be reduced.

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

  1 to 4 show a first embodiment of a method for manufacturing a strobe booster unit, wherein (a) is a plan view and (b) is a side view. As shown in FIGS. 1 to 4, a step-up control IC 12, a low-pass filter 13, and various electronic components 14 such as diodes are mounted on the upper surface 11 a of the printed circuit board 11. Conductive patterns 15 are provided at one end of the upper surface 11 a of the printed circuit board 11, and conductive patterns 16 and 17 are also provided at both ends of the lower surface 11 b of the printed circuit board 11.

  First, as shown in FIG. 1, the printed circuit board 11 is set inside a mold 18 of a molding machine (not shown). The mold 18 includes a printed circuit board storage unit 19 that stores the printed circuit board 11 and a step-up transformer storage unit 20 that is continuous with the printed circuit board 11. It is formed larger than the printed circuit board 11 so that a layer is formed. Similarly, in the step-up transformer housing portion 20, the inner peripheral surface is formed larger than the central core 22 so that a resin layer is formed on the outer peripheral portion of the central core 22 constituting the stroboscopic step-up transformer 21 described later.

After setting the printed circuit board 11 in the printed circuit board housing part 19 of the mold 18, the central core 22 constituting the strobe booster transformer 21 is housed inside the booster transformer housing part 20 of the mold 18. The central core 22 includes a central shaft portion 23 and both end portions 24 projecting in a direction perpendicular to the central shaft portion 23 at both ends thereof, and has an H-shaped core shape. Then, one end portion of the central core 22 is joined and positioned on the upper surface of the one end portion of the printed circuit board 11 so that the central shaft portion 23 of the central core 22 protrudes outward from the edge portion of the printed circuit board 11. .
Next, when a molten resin 25 such as an epoxy-based synthetic resin is injected into the mold 18, the gap between the printed board storage unit 19 and the printed board 11 and the gap between the step-up transformer storage unit 20 and the central core 22 are filled. The molten resin 25 is filled. As shown in FIG. 2, the outer peripheral portion of the printed circuit board 11 except the conductive patterns 15, 16, and 17 as the conductive parts of the printed circuit board 11, the various electronic components 14 mounted on the printed circuit board 11, and the central core 22. The outer peripheral portion of the central shaft portion 23 is sealed with a resin layer 25a, and one end portion of the central core 22 is fixed to the printed circuit board 11 and a winding bobbin 26 is formed. The conductive patterns 15, 16, and 17 are exposed by sealing with the resin layer 25 a except for the conductive patterns 15, 16, and 17 of the printed circuit board 11.

  Next, the printed circuit board 11 including the central core 22 sealed from the mold 18 is taken out, and the printed circuit board 11 is fixed to an automatic winding machine or the like, and the primary winding is wound around the winding bobbin 26 as shown in FIG. A coil layer 28 is formed by winding a coil 27 composed of a wire and a secondary winding. Further, as shown in FIG. 6, the lead wire 29 of the coil 27 is soldered to the conductive pattern 17 on the lower surface 11 b of the printed board 11.

  Next, as shown in FIG. 4, the side cores 30 and 30 made of an I-type core are positioned while adjusting the gap on both sides of the central core 22 on which the coil layer 28 is formed. It fixes to the both ends 24 with an adhesive agent. In this case, the strobe step-up transformer 21 with less variation in inductance can be manufactured by using the inspection machine and adjusting the gap G between the center core 22 and the side cores 30 and 30 to set the inductance of the coil 27.

  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.

The manufacturing process of the electronic flash boosting unit of the first embodiment of the present invention is shown, (a) is a plan view, (b) is a side view. The manufacturing process of the electronic flash boosting unit of the embodiment is shown, (a) is a plan view, (b) is a side view. The manufacturing process of the electronic flash boosting unit of the embodiment is shown, (a) is a plan view, (b) is a side view. The manufacturing process of the electronic flash boosting unit of the embodiment is shown, (a) is a plan view, (b) is a side view. The perspective view seen from the surface side of the flash pressure | voltage rise unit of the embodiment. The perspective view seen from the back surface side of the flash pressure | voltage rise unit of the embodiment. The perspective view seen from the surface side of the conventional strobe booster unit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Printed circuit board, 12 ... Boost control IC, 14 ... Electronic component, 21 ... Strobe boost transformer, 22 ... Center core, 26 ... Winding bobbin, 27 ... Coil, 28 ... Coil layer, 29 ... Lead wire, 30 ... Side core, G ... Gap

Claims (2)

In a strobe booster unit in which various electronic parts such as a strobe booster transformer and booster control IC are mounted on a printed circuit board,
Positioning one end portion of the central core constituting the strobe step-up transformer on the printed circuit board, and arranging the central shaft portion of the central core projecting outward from the edge portion of the printed circuit board ,
The printed circuit board leaving the conductive pattern portion of the printed circuit board, the various electronic components mounted on the printed circuit board, and the central shaft portion of the central core extending over the printed circuit board, the various electronic components, and the central shaft portion Sealing with a resin layer, fixing one end of the central core to the printed circuit board with the resin layer and forming a winding bobbin at the central shaft portion of the central core ,
Further, a coil layer is formed by winding a coil on the winding bobbin, and the lead wire of the coil layer is connected to the conductive portion exposed to the outside, and both sides of the central core on which the coil layer is formed The strobe booster unit is characterized in that the side core is fixed by adjusting the gap. In a method for manufacturing a strobe boost unit in which various electronic components such as a strobe boost transformer and a boost control IC are mounted on a printed circuit board,
Inside the mold, one end of the central core constituting the strobe step-up transformer is positioned on the printed circuit board, and the central shaft of the central core is temporarily fixed to protrude outward from the edge of the printed circuit board. Process,
The mold is filled with molten resin, and at least the conductive portion of the printed board is removed, and the printed board, the various electronic components mounted on the printed board, and the central shaft portion of the central core are sealed with a resin layer. A sealing step of stopping and fixing one end of the central core to the printed circuit board and forming a bobbin for winding;
The printed board including the central core sealed from the mold is taken out, a coil is wound around the bobbin for winding to form a coil layer, and the lead wire of the coil layer is connected to the conductive material of the printed board. Winding process to connect to the part,
A gap adjusting step of fixing the side core while adjusting the gap on both sides of the central core on which the coil layer is formed;
A method of manufacturing a strobe booster unit, comprising:

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