JPH06151189A - Flayback transformer and manufacture thereof - Google Patents

Abstract

PURPOSE:To eliminate leakage of resin when the resin such as epoxy is injected and hardened in the main body case of a transformer in the flyback transformer. CONSTITUTION:A coupling groove 14 is provided in main body case 2 of a transformer. A seal-packing liquid agent 15 is piled at the bottom surface of the coupling groove 14. When the seal-packing liquid agent 15 is hardened and rubberized, a sealing packing 15a is obtained. Under this state, a protruding part 19a of a volume outer case 19 is pressed into the coupling groove 14. Thus, the tight constitution is obtained with the deforming elasticity of the rubberized sealing packing 15a. In comparison with the conventional packing, wherein a sealing agent is applied from the outside after the main body case of a transformer and a volume outer case are assembled, there is no contamination in external appearance and the powerful sealing effect is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flyback transformer used in a TV receiver and the like and a method for manufacturing the flyback transformer.

[0002]

2. Description of the Related Art In recent years, a flyback transformer used as a high voltage generating transformer of a TV receiver has a transformer main body that generates a high voltage and a voltage dividing resistor that adjusts a focus voltage and a screen voltage. The structure that integrates the components is common.

The structure of a conventional flyback transformer will be described below with reference to FIG. In FIG. 6, 1 is a ferrite core that forms a magnetic path, and 2 is a transformer body case. Reference numeral 3 denotes a volume exterior case, which contains a focus voltage and screen voltage adjusting volume for supplying respective voltages to the focus electrode and the screen electrode of the cathode ray tube. Reference numeral 4 denotes a knob for rotating a contactor that comes into contact with the resistor of the volume and screen voltage adjusting volume provided in the volume exterior case 3. Reference numeral 5 is an epoxy resin that ensures insulation between the primary coil, the secondary coil and the rectifying diode of the transformer. The epoxy resin 5 is the transformer body case 2
Is filled inside.

FIG. 7 shows a fitting projection for connecting the transformer body case 2 and the volume exterior case 3. In FIG. 7, 10 is a fitting groove of the transformer body case 2, 11 is a fitting projection of the volume exterior case 3, and 13 is applied to the fitting portion to prevent liquid leakage when the epoxy resin 5 is injected. It is a shield material.

[0005]

As described above, conventionally, the shield member 13 is applied to the fitting portion from the outside after the fitting is performed. If the shield material 13 is not applied to the fitting portion from the outside, the injected resin of the epoxy resin 12 will penetrate into the gap between the fitting groove 10 of the transformer body case 2 and the fitting portion 11 of the volume exterior case 3. , Liquid leakage occurs before the epoxy resin 12 hardens, resulting in adhesion to the transformer body, poor appearance, or secondary failure such as focus of output lead from volume outer case 3 and adhesion to screen lead wire. To do. However, the shield material 13
There is a problem in that the work of applying the coating material from the outside is troublesome and that the shield material 13 before curing flows out from the coating position after the coating.

The present invention is to solve the above-mentioned problems, and without applying the shield material 13 to the fitting portion from the outside,
It is an object of the present invention to provide a flyback transformer capable of eliminating leakage of epoxy resin and a method of manufacturing the flyback transformer.

[0007]

In order to achieve the above object, the present invention uses a liquid hardening type seal packing for forming packing rubber on the bottom surface of the fitting groove of the main body case. That is, the liquid material for seal packing is put on the bottom surface of the fitting groove of the main body case, and in that state, the fitting protrusion of the volume exterior case is press-fitted into the fitting groove.

Further, a thermoplastic sealing packing material is provided along the fitting groove portion of the transformer body case, and the fitting projection portion of the volume outer case is press-fitted and joined.

[0009]

[Function] In the case where the liquid agent for seal packing is used, the liquid agent has high viscosity and fluidity, and can be applied even on a complicated fitting groove shape. Instead, it retains its shape immediately after application. Further, when it absorbs moisture in the air and hardens, it is fixed to the bottom surface of the fitting groove of the main body case with an adhesive force to be rubberized, and a sealing packing rubber having a soft hardness of about shear A30 is formed. . The fitting groove of the transformer body case coated with such packing rubber is press-fitted into the fitting portion of the volume exterior case. At that time, the packing rubber is deformed by the pressure of the fitting groove portion and fills the gap of the contact surface of the fitting portion.

Further, in the case where a thermoplastic sealing packing material is used, the packing material is sandwiched between the fitting groove on the main body case side and the protrusion on the volume exterior case side at the fitting portion, and the flyback transformer is used. If the resin is passed through a preheating furnace before being injected with epoxy, the thermoplastic seal packing material will be thermally deformed, further filling the gap in the fitting part, and a perfect sealing effect and fitting connection will be obtained. It is possible to eliminate resin leakage during casting.

[0011]

Embodiments of the flyback transformer of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1, FIG. 2 and FIG. 3 are drawings showing an embodiment corresponding to claim 1 and claim 2 in the scope of claims. In FIG. 1, reference numeral 2 denotes a transformer main body case, and a fitting groove 14 for accommodating the protrusion of the volume outer case opening is formed around the portion of the transformer main body case 2 where the volume outer case is mounted. FIG. 2 is a sectional view showing a portion of the fitting groove 14 of the transformer body case 2.

Reference numeral 15 is a liquid agent for seal packing, which is applied to the fitting groove 14 in a liquid state. Reference numeral 16 denotes a bottom surface of the fitting groove 14, that is, a bottom surface portion of the fitting groove. The liquid material 15 for seal packing is dispensed at the center of the bottom surface 16 of the fitting groove so as to form a semi-circular cross section with spaces on both sides. Reference numeral 18 is an applicator for applying the liquid agent 15 for seal packing, and 17 is a nozzle for application.

The manufacturing method will be described below. The seal packing liquid agent 15 in a highly viscous liquid state is discharged from the nozzle 17 and adheres to the fitting groove bottom surface portion 16. Once attached to the bottom surface 16 of the fitting groove, the seal packing liquid agent 15 is fixed, so that no fluid movement occurs and no spillage occurs from the fitting groove 14 of the transformer body case.

After a lapse of about 10 minutes in this state, the liquid material 15 for seal packing begins to harden its surface and becomes rubber. Along with the rubberization, an adhesive force is generated between the liquid material 15 for seal packing and the bottom surface portion 16 of the fitting groove.

FIG. 3 shows a joined state of the fitting portion. In FIG. 3, 19 is a volume exterior case. Reference numeral 5 is an epoxy resin, which is filled in the transformer body case 2 as in the conventional example shown in FIG. 15a is a transformer main body case 2 and a protrusion 1 of the volume exterior case 19.
The seal packing is sandwiched between 9a and 9a and is in a state where the seal packing liquid agent 15 is cured and turned into rubber.

As the protrusion 19a is press-fitted into the fitting groove 14 of the transformer main body case 2, the sealing packing 15a expands left and right around the bonding surface with the bottom surface 16 of the fitting groove and is deformed. Then, as shown in FIG. 3, the stopper rib 20 prevents the volume exterior case 19 from falling off, and the fitting is fixed.

Since the sealing packing 15a which spreads to the left and right is made of rubber, a repulsive elastic stress is generated due to the deformation, and the sealing packing 15a comes into close contact with the protruding portion 19a of the volume outer case 19. At this time, the sealing packing 15a is bonded to the bottom surface 16 of the fitting groove on the transformer body case 2 side so that no deviation occurs. Therefore, the transformer body case 2 and the volume outer case 19
Can maintain a stable close contact state through the sealing packing 15a.

Since the liquid material 15 for the seal packing progresses from the surface to the rubber, the projection 19a of the volume outer case 19 is press-fitted into the fitting groove 14 before the central portion thereof is completely rubberized. If combined, the gap between the transformer main body case 2 and the volume outer case 19 will be sealed by a soft sealing packing having a lower hardness, and the sealing packing 15a will be replaced by the transformer main body case 2
By following the joint surface of the volume outer case 19 and exhibiting a highly effective sealing property.

(Embodiment 2) Next, an embodiment corresponding to claim 3 of the scope of claims will be described with reference to FIGS. 4 and 5.

In FIG. 4, 2 is a transformer body case similar to that of the previous embodiment, and 14 is a fitting groove of the transformer body case 2. Reference numeral 21 is a volume exterior case, and 21a is a protrusion for fitting the volume exterior case 21. 4 and 5 are cross-sectional views of the fitting portion with the transformer body case 2 and the volume exterior case 21. 22 is a low hardness thermoplastic packing material.

FIG. 5 shows the joining state of the fitting portions. In the transformer body case 2, the projection 21a of the volume outer case 21 is fitted and joined in the fitting groove 14.

The side of the fitting groove 14 is tapered so that the width of the fitting groove 14 becomes narrower toward the bottom surface. On the other hand, volume exterior case 2
The protruding portion 21 a of the No. 1 is the fitting groove 1 of the transformer body case 2.
The width is slightly wider than the width of 4. Further, the ends of the protrusions 21a are formed so that their cross sections are semicircular.

The assembly process will be described below. The protrusion 21 a of the volume outer case 21 is inserted deeply into the fitting groove 14 of the transformer body case 2. As it is inserted deeply into the fitting groove 14, the projections 21a of the volume exterior case 21 have contact surfaces of their side surfaces, and are brought into close contact with each other.

Further, as the packing material 22 having a lower hardness is inserted, the end of the projection 21a of the volume outer case 21 is formed in a semicircular shape, so that the packing material 22 is pressed at a point.
It deforms so as to fill the gap between the fitting groove 14 and the projection 21a of the volume outer case 21, and the bottom surface of the fitting groove 14 and the projection 2 are deformed.
The gap between the end surface of 1a and the end surface is closed, and a sealing effect is produced.
The fitting is fixed by the stopper rib 20.

Before injecting the epoxy resin 5, the flyback transformer body is put in a preheating furnace. At this time, the thermoplastic packing material 22 inserted in the fitting groove 14 receives heat and has fluidity, and penetrates into the fitting gap of the details, and exhibits a more stable sealing effect.

As described above, this embodiment uses the thermoplastic packing material, paying attention to the fact that there is a step of heating the flyback transformer in the preheating furnace during the assembly process. The heat provided by the preheating furnace causes the thermoplastic packing material to increase in fluidity and enter into the small gaps of the fitting portion, and a stronger sealing effect is obtained. Since this packing material is deformed by heat after insertion, the cross-sectional shape of the packing material before insertion does not have to be along the cross-sectional shape of the fitting groove, and the lateral width of the packing material cross-section may be relatively thin. If the width of the packing cross section before insertion is narrow, the packing can be easily inserted into the fitting groove, and the complicated insertion work peculiar to the packing rubber can be reduced. In addition, it is possible to prevent epoxy resin leakage from the gap of the fitting part when injecting and curing the epoxy resin, resulting in poor appearance of the transformer due to resin leakage that has occurred in the past and adhesion of resin to output leads. It is possible to prevent secondary defects due to

[0028]

From the above description, when liquid packing rubber is injected into the fitting groove of the transformer body case and the fitting portion of the volume outer case is joined, assembly is easy and the packing rubber is unique. There is no complicated work of rubber insertion of
Since the rubber can be laid along the complicated fitting groove of the transformer body case in a liquid state in advance, it is possible to join while maintaining a stable sealing surface.

Further, in the case where the thermoplastic seal packing material is used, when the thermoplastic seal packing material is passed through the preheating furnace, the thermoplastic seal packing material is thermally deformed, further filling the gap of the fitting portion, and providing a perfect sealing effect and fitting. A bond is obtained.

Further, as compared with a conventional transformer body case and a volume outer case which are assembled and then a sealant is applied from the outer surface of the transformer body case, there is no stain on the external appearance.
The sealant is firmly fixed in the mating groove and exhibits a strong sealing effect. Therefore, when the epoxy resin is injected and cured, a stable shielding effect without leakage of the epoxy resin from the fitting gap can be obtained, and the work of applying the sealant can be performed in the pre-process of the assembly work. The work can be dried, and the work can be performed efficiently, and productivity can be improved and stability can be realized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a state in which a liquid agent for seal packing of a flyback transformer is applied in a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of the body case fitting portion of the flyback transformer according to the first embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view showing a joined state of the flyback transformer according to the first embodiment.

FIG. 4 is an enlarged sectional view of a fitting portion of a flyback transformer according to a second embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view showing a joined state of the flyback transformer according to the second embodiment.

FIG. 6 is an external view of a conventional flyback transformer.

FIG. 7 is an enlarged cross-sectional view of a volume outer case fitting portion in a conventional flyback transformer.

[Explanation of symbols]

 2 Transformer Main Body 5 Epoxy Resin 14 Fitting Groove 15 Liquid Agent for Seal Packing 16 Fitting Groove Bottom 17 Nozzle 18 Coating Machine 19 Volume Outer Case 19a Projection 20 Stopper Rib

Claims (3)

[Claims] 1. A flyback transformer comprising a transformer body case and a volume outer case fitted and joined together, wherein the transformer body case has a fitting groove in which a fitting projection of the volume outer case is housed. The fitting protrusion of the volume outer case is housed in the fitting groove of the transformer body case, and the liquid hardening type is already cured between the inner wall of the fitting groove of the transformer body case and the fitting protrusion of the volume outer case. A flyback transformer characterized in that a seal packing is interposed and an epoxy resin is filled in the transformer main body case. 2. A liquid sealing material is injected into the fitting groove of the transformer body case, and the fitting protrusion of the volume outer case is inserted into the fitting groove of the transformer body case in a state where the sealing material is hardened. A method for manufacturing a flyback transformer, characterized in that the transformer body case is filled with an epoxy resin. 3. A flyback transformer comprising a transformer body case and a volume outer case fitted and coupled together, wherein the transformer body case has a fitting groove in which a fitting projection of the volume outer case is housed. The fitting protrusion of the volume outer case is accommodated in the fitting groove of the transformer body case, and the thermoplastic sealing packing is provided between the inner wall of the fitting groove of the transformer body case and the fitting protrusion of the volume outer case. A flyback transformer in which a material is interposed and an epoxy resin is filled in the transformer body case.