JPH0519936Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a flyback transformer (hereinafter referred to as "FBT") used in television receivers and the like.

(b) Conventional technology Figure 4 shows a so-called multi-singler type FBT.
1 shows a circuit configuration diagram, in which 1 is a low-voltage coil as a primary winding, 2 is a high-voltage coil as a secondary winding, 3 is a core, and the secondary winding 2 has a plurality of winding sections 2a. , 2b, and 2c, and rectifier diodes D1, D2, and D3 are inserted and connected between each winding section.

By the way, the conventional circuit configuration as above
FBT is, for example, Utility Model Application No. 162993 (H02M7/
06), FIG. 3 shows a high voltage coil unit of an FBT having such a structure.

In FIGS. 3 and 5, reference numeral 16 is a high-voltage coil unit, in which the high-voltage coil 2 is divided into a cylindrical portion 19 of a hollow high-voltage coil bobbin 18 having flanges 17a and 17b at both ends. The thus formed winding sections 2a, 2b, 2c are sequentially wound in a laminated manner with a film-like insulating material 20 such as a polyester film for insulation interposed therebetween, and rectifier diodes D1, D2, D2 are connected in series between each winding section. D
3 are inserted and connected in sequence. The rectifier diode D3 at the highest voltage section is connected to terminals 24 and 29 provided on the collars 17a and 17b so as to straddle the high voltage coil 2. High voltage output lead wire 25
is held by a holding portion 26 provided on the collar portion 17a, and is connected to a terminal 26a to which a high output voltage is applied.

In the FBT high-voltage coil bobbin having the above configuration, creeping discharge is transmitted from the terminal 26a to the high-voltage lead wire 25 toward the tip of the lead wire 25.
Furthermore, before injecting the insulating resin into the insulating case (not shown) that houses the high voltage coil unit 16,
Since the high-voltage lead wire 25 is held by the holding portion 26, the high-voltage lead wire 25 is long and needs to be controlled during the insulating resin injection and curing process, which reduces the workability required for this process. Furthermore, resin may adhere to the high-voltage lead wire 25 due to a work error or the like, which impairs the appearance and reduces the value as a product. Further, since the curing process is carried out in an oven at a temperature of 120° C. for two hours or more, there are drawbacks such as deterioration of the insulation coating of the high voltage lead wire 25.

(c) Problems to be solved by the invention The present invention has been devised in view of the above points, and proposes an FBT that is easy to work with and has good electrical characteristics.

(d) Means for solving the problem In the FBT of the present invention, a high-voltage coil is divided into multiple sections to form winding sections, and each winding section is sequentially wound in a laminated manner with an insulating material interposed between each winding section. A high-voltage coil unit having a rectifier diode inserted in series therebetween, and a low-voltage coil unit having a low-voltage coil wound around a low-voltage coil bobbin are housed in combination. A part of the flange of the high-voltage coil bobbin is extended to form a holding part that fixes a metal cap into which one end of the high-voltage output lead wire is inserted and connected, and is press-fitted to the periphery of the holding part to close one end. At the same time, a cylindrical part for accommodating the lead wire inserted from the other end side to be connected to the metal cap is provided outside the high voltage coil bobbin integrally with the insulating case.

(E) Function As described above, since the cylindrical part for housing the high voltage lead wire is provided integrally with the insulating case on the outside of the high voltage coil bobbin, the high voltage lead wire can be connected after injecting and hardening the insulating resin. Furthermore, since the connection portion of the high voltage lead wire is provided on the open end side of the insulating case, the creepage distance can be increased.

(F) Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4 and 6. FIG. 1 is a diagram showing the structure of the main parts of the laminated multi-singular FBT of the present invention, and the circuit configuration is the same as FIG. 4.

In FIGS. 1 and 2, parts that are the same as those in the prior art are designated by the same reference numerals, and explanations thereof will be omitted. To explain the high voltage coil unit 16 in detail, as shown in FIG.
A has a terminal 21 to which the winding start end of the high voltage coil 2 is attached, terminals 22 and 23 to which the cathode terminals of the rectifier diodes D1 and D2 are connected, and a recessed protrusion 30 for holding the cathode lead of the rectifier diode D3; A holding part 3 having a metal cap 31 to which a cathode lead held by the protrusion 30 is connected.
2 is provided, and the other collar portion 17b is provided with terminals 27, 28, 29 to which the anode terminals of the rectifier diodes D1, D2, D3 are connected. The high voltage coil 2 starts winding from the terminal 21 as shown in FIG.
The rectifier diode D1,
The polarities of D2 and D3 are aligned in the same polarity direction as shown in FIG.

Therefore, the present invention proposes a flange 1 located on the open end side of the insulating case 33 as shown in FIG. 1 or FIG. 2b.
7a, the holding portion 32 formed in a columnar shape is provided at the tip of the leg portion 34 extending from the flange portion 17a,
At the center of the holding part 32 is a metal cap 3 with a bottom.
1 is fixed. Further, a cylindrical portion 35 is provided inside the insulating case 33, and the side wall 33a of the case 33 is a part of the cylindrical portion 35. A circular rib 36 is formed on one open end side of the cylindrical portion 35 through which the high voltage lead wire 25 is led out of the case 33 so that it can be closely fitted into the holding portion 32, and the tip thereof is A taper 37 is provided to enable smooth fitting with the holding portion 32. Said cylindrical part 3
The tip of the other open end of the lead wire 25 projects slightly beyond the upper surface 33b of the case 33, and is fitted with a rubber cap 38 to hold the lead wire 25. As shown in FIG. 1, a high-voltage coil bobbin 18 around which a high-voltage coil 2 is wound and rectifier diodes D1, D2, and D3 are arranged, and a low-voltage coil bobbin 39 around which a low-voltage coil 1 is wound are housed in an insulating case 33, and the high-voltage coil bobbin A holding portion 32 provided on the case 33 fits tightly into a circular rib 36 provided on the cylindrical portion 35 of the case 33. After injecting and hardening an insulating resin 45 such as epoxy resin into the insulating case 33, the outer sheath (vinyl chloride) at the tip of the high-voltage lead wire 25 is removed, and the tip is inserted into the cylindrical portion 35 and the tip is covered with a metal cap. 31 to make an electrical connection, the high voltage lead wire 25 does not get in the way during the injection hardening process of the insulating resin 45, and furthermore, the outer sheath of the high voltage lead wire 25 is removed in the furnace during curing. There is no need to worry about insulation deterioration. Connect the connection part of the high voltage lead wire 25 to the high voltage coil bobbin 1 on the open end side.
8, and forms a cylindrical portion 35 that accommodates the high voltage lead wire 25, so that the connecting terminal (metal cap) of the high voltage lead wire 25 and the tip portion of the cylindrical portion 35 are fitted with the rubber cap 38. This increases the creeping distance between the two parts and increases the effect of preventing creeping discharge.

Incidentally, after connecting the high-voltage lead wire 25, a resin that hardens at a relatively low temperature may be injected into the cylindrical portion 35.

In addition, 40 is made so that the film-like insulator 20 and the high voltage coil 2 do not protrude from the flanges 17a and 17b.
These are protrusions provided on the flanges 17a and 17b.

In addition, the leg portion 5 of the high voltage coil bobbin 18 in FIG.
6, a plurality of recesses 51 may be provided in order to increase the creepage distance between the low voltage portion of the high voltage coil 2 and the connection terminal of the high voltage lead wire 25.

(G) Effects of the invention As described above, according to the invention, the workability in the FBT assembly process is improved, and the reliability of the FBT insulation can be improved.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the structure of the FBT of the present invention.
Figures 2a and b are front and plan views showing the structure of the high voltage coil unit, Figure 3 is a diagram showing the winding method of the high voltage coil, Figure 4 is a diagram showing the circuit configuration of the FBT, and Figure 5. 1 is a diagram showing the structure of a conventional high voltage coil unit. Further, FIG. 6 is a diagram showing a main part of another embodiment of the present invention. 2... High voltage coil, 2a, 2b, 2c... Winding section, 16... High voltage coil unit, 20... Film insulator, 25... High voltage output lead wire, 3
1... Metal cap, 32... Holding part, 35...
Inner cylinder portion, D1, D2, D3...diodes.

Claims (1)

[Scope of utility model registration request] A high-voltage coil is divided into multiple sections to form winding sections, and each winding section is sequentially wound in a laminated manner through an insulating material on the winding section of a high-voltage bobbin that has flanges at both ends. A high-voltage coil unit consisting of rectifier diodes inserted and connected in series and a low-voltage coil unit consisting of a low-voltage coil wound around a low-voltage coil bobbin are combined and housed in an insulating case with one end open, and an insulating resin is placed inside the case. In a flyback transformer injected with a metal cap, a part of the flange of the high-voltage coil bobbin located on the open end side of the insulating case extends to fix a metal cap into which one end of the high-voltage output lead wire is inserted and connected. The cylindrical part is press-fitted to the periphery of the holding part, one end is closed, and the cylindrical part that accommodates the lead wire inserted from the other end to be connected to the metal cap is attached to the high-voltage coil bobbin. A flyback transformer characterized in that it is provided integrally with the insulating case on the outside.