JP2007294573A - Magnetic material device, manufacturing method thereof and discharge lamp lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and low-price insulating means for insulation between a magnetic material device and peripheral components thereof. <P>SOLUTION: The magnetic material device includes a magnetic core formed of a plurality of cores, a coil, and a bobbin 3 including a pin 4 for fixing the cores and coil and connecting the ends thereof. This magnetic material device includes a first insulator sheet 1 covering the external side of the integrated magnetic material cores, coil, and bobbin; and a second insulator sheet 2 covering the center of the magnetic material cores, and the bobbin 3 exposed under the condition to which the first insulator is mounted. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnetic device and a method for manufacturing the same, and is used, for example, in a discharge lamp lighting device that lights a discharge lamp.

  Conventionally, in order to insulate a magnetic device from peripheral components, a means for providing an insulating material 12 on the outer periphery of a magnetic device (for example, a transformer T1) is generally used as illustrated in FIG. In that case, in order to prevent the insulating material 12 from being removed by vibration or the like, it is necessary to fix the insulating material 12 with a fixing material 13 such as an adhesive. Further, assuming that the peripheral components a to g on the same substrate 11 fall down and approach the magnetic device T1, the magnetic device T1 and the peripheral components a to g must be physically separated.

Patent Document 1 discloses a structure in which an insulating tape is wound around the outer periphery of a transformer provided with a magnetic core, a coil, and a bobbin for fixing the core and the coil, and the resin is stored in a case and injected and filled. It has been proposed to increase the adhesion between the resin and the insulating tape while improving the workability of winding the insulating tape by providing a narrow tape adhesive portion between the inner surface of the insulating tape and the outer periphery of the coil.
Japanese Utility Model Publication No. 7-36419

  In the structure in which the frame-shaped insulating material as shown in FIG. 10 is provided on the outer periphery of the magnetic device, the circuit device is increased in size and cost. In addition, if the outer periphery of the magnetic device is surrounded by such a frame-shaped insulating material, particularly in a forced air cooling environment, the insulating material interferes with the forced air cooling air, and not only the magnetic device, but also the temperature of the peripheral components. It will be high. In the structure disclosed in Patent Document 1, since resin filling is necessary, the cost is increased, and a case for housing the entire transformer filled with resin is also necessary, which increases the size.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a magnetic device having a small and inexpensive insulating means and a method for manufacturing the same.

  As shown in FIGS. 1 to 8, the invention of claim 1 includes a plurality of magnetic cores 7, coils 5, pins 4 that fix the cores 7 and 5 and connect the ends of the coils 5. In the magnetic body device including the bobbin 3 having a sheet, the sheet-like first insulator 1 covering the outside of the state in which the magnetic body core 7, the coil 5, and the bobbin 3 are integrated, and the first insulator 1 are attached. The magnetic core 7 exposed in the applied state and the sheet-like second insulator 2 covering the central portion of the bobbin 3 are provided.

  A second aspect of the present invention is a discharge lamp lighting device (see FIG. 9) including the DC-DC converter circuit 10 having the magnetic device of the first aspect.

  As shown in FIGS. 1 to 8, the invention of claim 3 includes a plurality of magnetic cores 7, coils 5, pins 4 that fix the cores 7 and 5 and connect the ends of the coils 5. A method of manufacturing a magnetic body device comprising a bobbin 3 having a step of forming a coil 5 by winding a wire 5a around the bobbin 3 (FIG. 2) and a bobbin 3 around which the coil 5 is wound. The step of attaching the core 7 (FIG. 5), and the sheet-like first insulator 1 is attached to the outer periphery of the bobbin 3, the coil 5 and the magnetic core 7 integrated (FIG. 6). A step of folding the protruding portion inward (FIG. 7) and attaching the sheet-like second insulator 2 so as to cover the exposed portion of the magnetic core 7 or the coil 5 from the first insulator 1 ( FIG. 8).

  According to the first aspect of the present invention, since the insulating means between the magnetic device and the peripheral parts is concentrated in the magnetic device, there is no need for an insulating material or a fixing material for fixing the insulating material. Can be cheap. In addition, since an insulating material is not provided between the magnetic body device and the peripheral parts, or a fixing material for fixing the insulating material is not required, the appearance is clean and the product quality can be improved. Furthermore, existing general-purpose bobbins and cores that could not be used with the conventional structure can also be used, so there are advantages in terms of price, downsizing, delivery, design freedom, mounting equipment, winding equipment, inventory management, etc. There is.

  According to the invention of claim 2, the same effect as that of claim 1 can be obtained in the insulation means on the primary side and the secondary side of the DC / DC converter circuit, and particularly strong insulation such as reinforced insulation is required. In some cases, the above effects are very high.

  According to the invention of claim 3, the same effect as that of claim 1 can be obtained, the manufacture is easy, and the processing cost can be reduced.

(Embodiment 1)
FIG. 1 is a perspective view showing an appearance of a magnetic device according to Embodiment 1 of the present invention. In the figure, 1 and 2 are insulators, 3 is a bobbin, and 4 is a pin. The insulator 1 covers the upper surface and outer periphery of the magnetic core attached to the bobbin 3, and the insulator 2 covers the lower surface of the magnetic core that cannot be completely covered by the insulator 1. Hereinafter, the manufacturing process of the magnetic body device of FIG. 1 will be described with reference to FIGS.

  FIG. 2 is a perspective view showing the external appearance of the bobbin 3 before the magnetic core is mounted. The bobbin 3 includes a pair of rectangular parallelepiped base portions 3a, a U-shaped flange portion 3b protruding from the upper surface of the base portion 3a, and a coil winding portion 3c formed between the pair of flange portions 3b. And is integrally formed of a resin molded product or the like. A plurality of pins 4 for electrical connection are planted in the base portion 3 a of the bobbin 3. These pins 4 may be integrally formed with the bobbin 3 by forming an insert.

  Each pin 4 is connected to an end 5b of a wire 5a constituting a coil of the magnetic device. In the example of FIG. 2, the end 5 b of the wire 5 a is entangled with the root of the pin 4. The wire 5a is wound around the coil winding portion 3c of the bobbin 3 to become a coil of the magnetic device. When the magnetic device is a choke coil, only one coil is required. However, when the magnetic device is a transformer, a primary winding and a secondary winding are formed in the same manner, and end portions of the respective windings are formed. Is connected to pin 4.

  Although not particularly illustrated, a plurality of similar pins 4 may be planted on the other base portion 3a of the bobbin 3. Further, there may be a pin 4 to which no wire is connected. These pins 4 can be used as fixing means for the magnetic device by being inserted into holes in the board and soldered from the back when mounted on a printed board.

  FIG. 3 is a perspective view showing an appearance of the bobbin 3 around which the coil 5 is wound. A wire forming the coil 5 is wound around the coil winding portion of the bobbin 3. Reference numeral 6 denotes a fixing material, which fixes the wound coil 5. The fixing member 6 may be an insulating sheet used for covering the outer periphery of a general transformer winding.

  FIG. 4 is a perspective view showing the appearance of the magnetic core 7 mounted on the bobbin 3. By joining the pair of E-shaped cores 7 so as to face each other, a Japanese character-shaped magnetic circuit is configured as a whole. Each E-shaped core 7 includes a substantially U-shaped outer foot portion 7a and an inner foot portion 7b on a flat plate provided at the center of the outer foot portion 7a. The inner foot portion 7 b has a shape that can be inserted into the coil winding portion 3 c from the flange portion 3 b of the bobbin 3, and the outer foot portion 7 a has a shape that is placed on the base portion 3 a of the bobbin 3.

  An insulator A is attached to the outer leg portion 7 a of the core 7. This insulator A is provided to insulate the core 7 from the pins 4 and covers a portion of the lower surface of the core that contacts the base portion 3a of the bobbin 3 and covers most of the side surface of the outer foot portion 7a. However, the upper surface of the core is not covered.

  FIG. 5 is a perspective view showing a process of attaching the pair of magnetic cores 7 to the bobbin 3 around which the coil is wound. The flat inner legs 7b of each E-shaped core 7 are inserted into the core insertion part 3d of the bobbin 3 as indicated by arrows. At this time, the lower surface side of the outer leg portion 7 a of the E-shaped core 7 contacts the base portion 3 a of the bobbin 3, but this portion is covered with the insulator A.

  FIG. 6 is a perspective view showing a process of attaching the insulator 1 to the magnetic core 7 attached to the bobbin. The insulator 1 is applied to the outer periphery in which the coil 5, the bobbin 3 and the core 7 are integrated, and the entire outer periphery of the side surface of the core 7 is covered as indicated by the arrows in the figure. Here, the width H of the insulator 1 is larger than the height h of the outer foot portion 7a of the core 7 and covers all the side surfaces of the core 7 so as to protrude to the upper part. The portion of the insulator 1 that protrudes above the core 7 is used to cover the upper surface of the core that is not covered with the insulator A.

  FIG. 7 is a perspective view showing a process of covering the upper surface side of the magnetic core with the insulator 1 so as to wrap. A portion of the insulator 1 that protrudes above the core 7 is bent as indicated by an arrow in the figure to cover the upper surface of the coil 5, the bobbin 3, and the core 7 that are integrated. In FIG. 7, a vacant part is shown in the upper part with the insulator 1 folded inward, but it does not matter whether this vacant part is present or not.

  FIG. 8 is a perspective view showing the last step. In the state where the coil 5, the bobbin 3 and the core 7 are integrated, the insulator 2 is applied in a direction parallel to the arrangement direction of the pins 4 of the bobbin 3. At this time, the insulator 2 is applied so as to cover all portions of the insulator 1 that do not cover the lower surface of the core. If there is a vacant part at the top, the insulator 2 is wound as shown by the arrow in the figure so as to cover the vacant part. Thereby, the magnetic body device of FIG. 1 is completed. In addition, the sheet-like insulator used in the present invention may be, for example, a general insulating tape whose one side is sticky and cut into an appropriate length, width, and shape.

(Embodiment 2)
FIG. 9 is a circuit diagram showing an example of a discharge lamp lighting device having a DC / DC converter circuit using the magnetic device of the present invention. 8 is a power factor correction circuit, 9 is a discharge lamp lighting circuit, and 10 is a DC / DC converter circuit. The voltage supplied from the AC power supply V is rectified by the diodes D1 to D4, and the power factor is improved by eliminating the pause period of the input current by the step-up chopper circuit including the switching element Q1, the diode D5, the choke coil L2, and the capacitor C3. . L1 is a common filter, and C1 and C2 are filter capacitors.

  The discharge lamp lighting circuit 9 converts the voltage smoothed by the capacitor C3 into a voltage by a step-down chopper circuit including a switching element Q2, a diode D6, and a choke coil L3, and supplies the converted voltage to the capacitor C4. It is converted into alternating current by a full bridge type polarity inverting circuit composed of Q6 and applied to the discharge lamp La via the choke coil L4.

  In the DC / DC converter circuit 10, the voltage smoothed by the capacitor C3 is switched at a high frequency by the switching element Q7 and applied to the primary winding T1-1 of the transformer T1, and the secondary winding T1-2 of the transformer T1. Convert voltage to. The output voltage of the secondary winding T1-2 of the transformer T1 is rectified by the diode D7, smoothed by the capacitor C5, and applied to the load R1 of the DC / DC converter. For example, the voltage of the capacitor C3 is 370V, the number of turns of the primary winding T1-1 of the transformer T1 is 90 turns, the number of turns of the secondary winding T1-2 of the transformer T1 is 13 turns, the core is ferrite, and the bobbin is EFD25 type. The output voltage of the DC / DC converter circuit 10 is set to 12V.

  By using the above-described first embodiment for the transformer T1 of the DC / DC converter circuit 10, an insulating structure between the magnetic device and the peripheral parts is established, which can be made smaller and less expensive than the conventional one. In particular, when a strong insulation such as a reinforced insulation is required, the above-described effect becomes extremely high.

It is a perspective view which shows the external appearance of the magnetic body apparatus which concerns on Embodiment 1 of this invention. It is a perspective view which shows the process of winding a coil around a bobbin. It is a perspective view which shows the external appearance of the bobbin by which the coil was wound. It is a perspective view which shows the external appearance of the magnetic body core with which a bobbin is mounted | worn. It is a perspective view which shows the process of mounting | wearing with a pair of magnetic body core to the bobbin by which the coil was wound. It is a perspective view which shows the process of mounting | wearing with an insulator to the magnetic body core with which the bobbin was mounted | worn. It is a perspective view which shows the process of covering so that the upper surface side of a magnetic body core may be wrapped with an insulator. It is a perspective view which shows the last process. It is a circuit diagram which shows an example of a discharge lamp lighting device provided with the DC / DC converter circuit using the magnetic body apparatus of this invention. It is a front view which shows an example of component arrangement | positioning on the board | substrate of a prior art example.

Explanation of symbols

1 Insulator 2 Insulator 3 Bobbin 4 Pin 5 Coil 6 Fixing Material 7 Core A Insulator

Claims (3)

In a magnetic device comprising a plurality of magnetic cores, a coil, and a bobbin having a pin that fixes the core and the coil and connects the ends of the coil, the magnetic core, the coil, and the bobbin are integrated. A sheet-like first insulator that covers the outside of the sheet, a magnetic core that is exposed when the first insulator is attached, and a sheet-like second insulator that covers the center of the bobbin. A magnetic device characterized by that. A discharge lamp lighting device comprising a DC-DC converter circuit having the magnetic device of claim 1. A method of manufacturing a magnetic device comprising a plurality of magnetic cores, a coil, and a bobbin having a pin that fixes the core and the coil and connects the ends of the coil. The step of attaching the magnetic core to the bobbin around which the coil is wound, and the sheet-like first insulator is attached to the outer periphery of the integrated bobbin, coil and magnetic core And a step of attaching a sheet-like second insulator so as to cover the exposed portion of the magnetic core or coil from the first insulator so that the portion protruding from the outer periphery is inside. Manufacturing method of body device.

Images