JPH0331053Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a flyback transformer that supplies high voltage to, for example, a television receiver, and particularly to a flyback transformer in which the pin pedestal and the insulating case are spaced apart. Regarding trance.

[Conventional technology]

FIG. 4 shows a flyback transformer according to the prior art. In the figure, reference numeral 1 denotes a cylindrical low-voltage coil bobbin around which a low-voltage coil (not shown) is wound, and a cylindrical high-voltage coil bobbin 2 is fitted around the outer periphery of the low-voltage coil bobbin 1. Reference numeral 3 denotes a substantially U-shaped core fitting part formed on one end side of the low voltage coil bobbin 1, and the core fitting part 3 is connected to a curved wall 3A along the outer peripheral surface of the one end side of the low voltage coil bobbin 1, and from the curved wall 3A. It consists of opposing walls 3B, 3B extending parallel to the tangential direction and projecting to the outside of the low-voltage coil bobbin 1. The tip of each opposing wall 3B is bent outward at a right angle, and each of the insulating cases 8, which will be described later, The fitting portions 4, 4 are slidably fitted into the groove 10.

5, 5... are a plurality of pin pedestals formed protruding from the outer surface of the core fitting part 3 at predetermined intervals, and the low voltage coil bobbin 1 is attached to the end surface of the pin pedestal 5 along the axial direction of the low voltage coil bobbin 1. Terminal pins 6, 6, . . . are implanted in the opposite direction from 1. Of each pin pedestal 5, an insulating case 8 is provided at the tip of the pin pedestal 5A located at the center of the curved wall 3A of the core fitting portion 3.
An engaging protrusion 7 that engages with the pin base 5A is formed along the protruding direction of the pin pedestal 5A, and a concave groove 7 is formed on the tip surface of the protrusion 7 along the axial direction of the low-voltage coil bobbin 1.
A is formed.

Reference numeral 8 denotes an insulating case made of an insulating material that is externally fitted from the other end of the low-voltage coil bobbin 1 to the core fitting part 3 so as to cover the high-voltage coil bobbin 2. The insulating case 8 is open on one side and open on the other side. consists of a closed hollow body. A notch 9 into which the core fitting portion 3 is fitted is formed in a thick wall portion 8A located on one side of the insulating case 8.
Each insertion part 4 of the core fitting part 3 is provided on the end face of the cutout part 9.
Grooves 10, 10 are formed to be slidably fitted,
In addition, an insulating case 1 is located on the opposite side of the wall portion 8A.
A protrusion 11 that fits into the groove 7A of the engagement protrusion 7 is formed on the inner surface of the protrusion 11 .

The flyback transformer according to the conventional technology is constructed as described above, and has a high voltage coil bobbin 2 on the outer periphery.
The low voltage coil bobbin 1, which is fitted externally, is inserted into the insulating case 8. At this time, each fitting part 4 of the core fitting part 3 is slidably fitted into each groove 10 of the insulating case 8,
Further, by engaging the engagement protrusion 7 of the low voltage coil bobbin 1 with the protrusion 11 of the insulating case 8, displacement of the low voltage coil bobbin 1 in the radial direction and the circumferential direction with respect to the insulating case 8 is restricted. As a result, when each terminal pin 6 is inserted into each pin insertion hole provided on the printed circuit board to assemble the flyback transformer, each terminal pin may become misaligned and cannot be inserted. will not bend or twist.

In recent years, flyback transformers have been known in which the low voltage coil bobbin has been made smaller and the insulating case has been made larger in order to dispose a capacitor or a plurality of diodes between the insulating case and the high voltage coil bobbin. In a flyback transformer with such a structure, the distance between the pin pedestal and the insulating case becomes large (see Figure 2), so in order to prevent displacement of the low voltage coil bobbin in the circumferential direction, an engaging part is provided that protrudes from the pin pedestal. Although the protruding length of the protruding piece 7 must be made long, this configuration has the disadvantage that it becomes an obstacle when winding a low voltage coil around the low voltage coil bobbin 1 using an automatic winding machine.

In addition, some flyback transformers are equipped with a fitting opening on one side of the insulating case for fitting a resistance case that accommodates high-voltage resistors such as focus resistors and screen resistors. Therefore, the insulating case becomes easily deformed, and when the flyback transformer is mounted on a printed circuit board, the terminal pins may be misaligned, resulting in poor connection or bending of the terminal pins. Furthermore, it is necessary to fill the insulating case 8 with resin and mold the low-voltage coil, high-voltage coil, etc. Therefore, when inserting the injection nozzle into one end of the insulating case 8 and filling it with resin, the engagement protrusion 7 gets in the way and there is a drawback that the resin injection operation cannot be carried out smoothly.

[Problems to be solved by the invention] The present invention was devised in view of the above-mentioned shortcomings of the prior art. The objective is to provide a flyback transformer with a

[Means for solving problems]

The features of the means adopted by the present invention in order to solve the above-mentioned problems are that locking protrusions are provided on the pin pedestals located at substantially opposite positions among the pin pedestals to protrude toward the insulating case; A locking portion with which the locking projection engages is provided on the inner surface of the insulating case.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 3. In each embodiment, the same components as those of the prior art described above are denoted by the same reference numerals, and the explanation thereof will be omitted.

FIG. 1 shows a first embodiment of the invention.

In the figure, 21 is a core fitting part integrally formed on one end side of the low-voltage coil bobbin 22, and the core fitting part 21 has a curved wall 21A, a pair of opposing walls 21B, 21B, each of which has a substantially U-shaped planar shape, and the distal end of each opposing wall 21B protrudes in a step-like manner.
It's getting old. Further, on the outer surface of the core fitting part 21, a plurality of pin pedestals 24 ₁ are arranged at predetermined intervals.
24 ₂ ...24 ₁₀ are formed protrudingly.

Reference numeral 25 denotes an insulating case that is larger than the insulating case 8 according to the prior art, and has a peripheral wall partially bulging out to form a housing portion 25A for a diode, etc., and is formed on one side of the insulating case 25. A notch 26 into which the core fitting portion 21 described above is fitted is formed in the thick wall portion 25B. In addition, the wall portion 2
A pair of protruding walls 27, 27 are formed at right angles on the outer surface of 5B, and each protruding wall 27 has an L-shaped engagement portion into which each insertion portion 23 of the core fitting portion 21 is slidably fitted. Matching grooves 28, 28 are formed to face each other.

29, 29 are pin pedestals 24 ₁ located at substantially opposite positions among the respective pin pedestals 24 ₁ to 24 ₁₀ ;
24 A locking protrusion formed in a "C" shape protruding from ₁₀ toward the insulating case 25, and each protrusion 25
Contact surfaces 29A, 29A are formed in parallel to the protruding direction of each pin pedestal 24 ₁ , 24 ₁₀ .

Reference numerals 30 and 30 denote locking portions that are located on both sides of the notch portion 26 and are recessed in an “L” shape on the inner surface of the wall portion 25B, and are parallel to the protruding direction of each of the pin pedestals 24 ₁ and 24 ₁₀ . The surface serves as a receiving surface 30A against which each of the contact surfaces 29A abuts.

The present embodiment is constructed as described above, and the low voltage coil bobbin 22, on which the high voltage coil bobbin 2 is fitted around the outer periphery, is inserted into the insulating case 25. At this time, each insertion part 23 of the core storage part 21 is slidably fitted into each engagement groove 28 of the insulating case 25, and the locking projections of the pin pedestals 24 ₁ and 24 ₁₀ located on the left and right positions in the figure The low voltage and high voltage coil bobbins 22, 2 are assembled into the insulating case 25 by bringing the coil bobbins 29 into contact with the locking portions 30 of the insulating case 25.

According to this embodiment, the locking protrusions 29 are formed on the pin pedestals 24 ₁ and 24 ₁₀ located at opposing positions, and the insulating case 25 has a locking portion 30 with which each of the protrusions 29 comes into contact. Because of the structure in which the low voltage coil bobbin 22 is provided, even if the low voltage coil bobbin 22 tries to rotate in the circumferential direction, the contact surface 29A of each locking protrusion 29 hits the receiving surface 30A of the locking part 30 and is restricted. Also, the positions of the pin pedestals 24 ₁ to 24 ₁₀ integrally formed therewith do not shift.

Next, FIG. 2 shows a second embodiment of the present invention.
In this embodiment and the third embodiment described later, the same components as those in the first embodiment described above are given the same reference numerals, and the explanation thereof will be omitted.

However, the feature of this embodiment is that among the pin pedestals 24 ₁ to 24 10 arranged along the outer surface of the core fitting part 21, the pin pedestals 24 ₁ , _{24 10 located} at both ends Parallel surfaces 31A, 31A along the protruding direction of each pin pedestal 24 ₁ , 24 ₁₀ , and inclined surfaces 31B, 31B inclined with respect to the protruding direction.
The inner surface of the wall 25B of the insulating case 25 has a "V" shape located on both sides of the notch 26 with each groove surface 32A, 32B serving as a receiving surface. The reason is that the locking portions 32, 32 having the shape of the shape are recessed.

According to this embodiment configured as described above, each locking protrusion 31 provided on the pair of pin pedestals 24 ₁ and 24 ₁₀ engages with each locking portion 32 of the insulating case 25, and as a result, the low voltage coil bobbin 22 rotates in the circumferential direction, the parallel surface 31A of each protrusion 31 engages the locking portion 3.
Its rotation is restricted by contacting one side receiving surface 32A of 2. Furthermore, when the low-voltage coil bobbin 22 attempts to displace in the radial direction, that is, in the direction of the housing portion 26A of the insulating case 26, the inclined surface 31B of each locking projection 31 comes into contact with the other side receiving surface 32B of each locking portion 32. As a result, displacement of the low voltage coil bobbin 22 in the radial direction is restricted.

FIG. 3 shows a third embodiment of the invention.

The feature of the third embodiment is that the pin pedestals 24 ₁ and 24 _10, which are substantially opposite to each other at both ends of each pin pedestal 24, have locking protrusions 41 and 41 having round bar-shaped tips 41A. The pin pedestal 24 ₁ ,
24 _{and 10} , and the tip portions 41A of each of the locking protrusions 41 are slidably fitted onto the inner surface of the wall portion 25B of the insulating case 25 on both sides of the notch portion 26. Locking part 4 of the concave circular groove that fits
2,42 was formed.

The present embodiment is constructed as described above, and each locking protrusion 41 protruding from the pin pedestals 24 ₁ and 24 ₁₀ located at substantially opposite positions is attached to the insulating case 24 .
As a result, the low-voltage coil bobbin 22 is reliably prevented from rotating in the circumferential direction or displacing in the radial direction, as in the second embodiment. can.

In addition, in each embodiment, each locking protrusion 29, 31,
Reference numeral 41 denotes a pair of pin pedestals 24 ₁ , 24 located near the tip of the core fitting part 21 and disposed facing each other.
₁₀ , each locking protrusion 2
The pins 9, 31, and 41 may be provided to protrude toward the locking portions 30, 32, and 42 from other pin pedestals, such as the pin pedestals 24 ₃ and 24 ₉ , as long as they are substantially opposed to each other.

[Effect of idea]

According to the present invention configured as detailed above,
By providing locking protrusions on the pin pedestals located at substantially opposite positions, and providing a locking part on the insulating case with which the locking protrusions engage, the low-voltage coil bobbin is secured in the circumferential direction and radially within the insulating case. Since we have made it possible to reliably prevent movement in the direction of the flyback transformer, when installing the flyback transformer on a printed circuit board, we can ensure that the terminal pins will not be misaligned, resulting in poor connection or bending of the terminal pins. This makes it possible to improve the reliability and work efficiency of the flyback transformer.

[Brief explanation of drawings]

Figures 1 to 3 are the first to third figures of the present invention.
A bottom view of a flyback transformer according to an embodiment of
FIG. 4 is a bottom view of a flyback transformer according to the prior art. 2...High voltage coil bobbin, 6...Terminal pin, 2
1... Core fitting part, 21B... Opposing wall, 22...
Low voltage coil bobbin, 24...Pin pedestal, 25...
Insulating case, 29, 31, 41...Latching protrusion,
30, 32, 42...Locking portion.

Claims (1)

[Scope of utility model registration request] A cylindrical low-voltage coil bobbin into which a high-voltage coil bobbin is externally fitted, a substantially U-shaped core fitting portion formed on one end side of the low-voltage coil bobbin, and a core fitting portion protruding outward from the outer surface of the core fitting portion. A flyback comprising a plurality of pin pedestals with terminal pins implanted in the tip portion thereof, and an insulating case externally fitted from the other end of the low voltage coil bobbin to the core fitting portion so as to cover the high voltage coil bobbin. In the trance,
Among the pin pedestals, the pin pedestals located at substantially opposing positions are provided with locking protrusions that protrude toward the insulating case, and the locking protrusions engage with the inner surface of the insulating case. A flyback transformer characterized by having a locking part.