JPH0221677B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of assembling a shield case used in an electronic tuning tuner of a television receiver.

(B) Prior Art Conventionally, a method as shown in FIG. 1 has been used to house and fix a printed board in which high-frequency circuit components are incorporated in a metal frame forming a shield case.

In FIG. 1, reference numeral 1 denotes a metal frame, and a side surface 1a of the frame 1 includes a connector 2 to which a cable led out from an antenna terminal of a television receiver is connected, and a plurality of external connection tuner terminals 3. is provided. Then, on the side surface 1a of the metal frame 1, there are appropriately cut and raised portions 1b and protruding portions 1c [see FIG. 2].
These cut-and-raised portions 1b and protruding portions 1
After temporarily fixing the printed board 4 as shown in step c, either solder it manually (the soldering points are indicated by diagonal lines in Fig. 1), or temporarily fix the printed board 4 to the metal frame 1 as described above. After that, soldering was performed by the solder dipping method as shown in FIG. In Fig. 2, the same parts as in Fig. 1 are given the same figure numbers, 5 is the solder dipping tank, 6 is the solder dipping tank.
is molten solder.

By the way, when soldering is performed manually as described above, not only is productivity bad because there are many soldering points, but also it takes a lot of time to solder the metal frame 1 and the metal foil (not shown) of the printed board 4. If a large-capacity soldering iron is required and chip-shaped parts are used as parts to be incorporated into the printed circuit board 4, heat the parts in advance so that the chip-shaped parts are not damaged by the heat applied during soldering. It is necessary to (preheat).

The solder dipping method eliminates the disadvantages of the manual work described above, but the molten solder 6 in the solder dipping tank 5 is
Since the metal frame 1 is immersed in the metal frame 1, the molten solder 6 adheres to the side surface 1a of the metal frame 1. Therefore, when the open end 1d of the metal frame 1 is covered with the metal cover 7 as shown in FIG. The problem was that the cover caused shock noise. Furthermore, in the past, it was necessary to temporarily fix the printed boards, resulting in poor productivity.

(c) Purpose of the Invention It is an object of the present invention to provide a method for assembling a shield case that is designed to avoid the above-mentioned drawbacks.

(D) Structure of the Invention The present invention provides a method in which a plurality of protrusions are integrally formed at at least one open end of a metal frame, and a V-cut groove is provided in a printed board along the open end of the metal frame. A through hole through which the protruding piece is inserted is provided in the V-cut groove, and by inserting the protruding piece into the through hole, the protruding piece protruding from the printed board and the metal foil provided on the printed board are connected. After joining with solder, the printed board is split at the V-cut groove to remove the portion protruding from the metal frame, and a metal cover is attached to the one open end so that the protruding piece is in contact with the inner surface. This is a method of assembling a shield case.

(E) Embodiment A method of assembling the shield case of the present invention will be explained with reference to FIGS. 4 to 8, and the same parts as those in the conventional method are given the same figure numbers.

FIG. 4 shows a metal frame 8, and a side surface 8a of the frame 8 is provided with a connector 2 and a tuner terminal 3 for external connection, as well as a metal partition wall 9 as required. and the metal frame 8
A plurality of protrusions 10 are integrally formed at the open end 8b of. In this embodiment, a protruding piece 11 is also formed on the partition wall 9.

On the other hand, as shown in FIG. 5, a V-cut groove 13 [fifth
In the figure, since the V-cut groove 13 is formed on the back surface of the printed board 12, it is indicated by a broken line.
Next, a through hole 14 is provided in the portion where the V-cut groove 13 is formed, into which the protruding piece 10 provided at the open end 8b of the metal frame 8 is inserted, and the protruding piece 11 provided on the partition wall 9 is inserted. Through-hole 15 to be inserted
is provided.

The printed board 12 has metal foils 16 and 17 necessary for coupling the metal frame 8 and the printed board 12, in addition to a conductive pattern (not shown) formed for electrical connection of circuit components mounted on the printed board 12. The hatched portion in FIG. 5 is formed in advance near the through holes 14 and 15, and
The metal foil 16 formed in the vicinity of the through hole 14 through which the protruding piece 10 formed in b is inserted is provided within the range surrounded by the V-cut groove 13 as shown in FIG.

Next, each protrusion 1 of the metal frame 8 is inserted into the through holes 14 and 15 of the printed board 12 processed as described above.
0 and 11, the printed board 12 is assembled so that the protrusions 10 and 11 protrude from the surface of the printed board 12 on which the metal foils 16 and 17 are formed, as shown in FIG.

The semi-finished product assembled in this way is immersed in molten solder in a solder dipping tank while holding the edge of the printed board 12.
Solder is applied to the surface on which the metal foils 16 and 17 are formed. As a result, the metal foils 16, 17 and the protrusion 1
0 and 11 are soldered, and the printed board 12 is fixed to the metal frame 8.

Thereafter, the printed board 12 is split along the V-cut groove 13, and the portion protruding from the metal frame 8 is removed.

Then, as shown in FIG. 7, a metal back cover 18 having a plurality of elastic claw pieces 18a that engages with the side surface 8a of the metal frame 8 is applied. At this time, protruding pieces 10 protruding from the through holes 14 and 15 of the printed board 12,
11 comes into contact with the bottom portion 18b of the inner surface of the back cover 18, so that the elastic claw pieces 1 of the back cover 18
The locking position of 8a is determined. Note that a claw piece 18 provided on the back cover 18 as necessary
a is provided so as to be located between the projecting pieces 10. In this way, the back cover 18 can be attached smoothly. Further, in order to prevent the cut surface of the V-cut groove 13 from coming into contact with the side wall 18c of the back cover 18, it is preferable to swell the side wall 18c slightly outward as shown in FIG.

Thereafter, a metal front cover 19 having a plurality of claw pieces 19a is applied to the other open end of the metal frame 8, thereby completing the shield case.

In the above embodiment, four V-cut grooves 13 are provided, but as shown in FIG. 8, the printed board 12 is formed in advance so as to match one width of the metal frame 8. Two V-cut grooves 13 may be provided along the other width of the body 8, and the printed board 12 may be split at the V-cut grooves 13 after soldering to remove unnecessary portions of the printed board 12. .

(F) Effects of the Invention According to the method for assembling a shield case of the present invention, there is no need to temporarily fix the printed board to the metal frame, thereby improving productivity.

In addition, even though soldering is carried out using the solder dipping method, the solder does not adhere to the side surfaces of the metal frame, so there is no contact failure between the metal cover and the metal frame as in the past, and the contact failure is avoided. The present invention is extremely useful, since the inconveniences caused by this can be avoided.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the main parts of a shield case assembled by the conventional method, Fig. 2 is a diagram showing the conventional assembly method, and Fig. 3 is a plan view of the shield case assembled by the conventional method. FIG. Figures 4 and 5 are plan views of parts used in the present invention, Figure 6 is a diagram for explaining the assembly method of the present invention, and Figure 7 is a shield case assembled by the method of the present invention. FIG. 8 is a diagram for explaining another embodiment. 8...Metal frame body, 8b...Open end, 10...Protrusion piece, 12...Printed board, 13...V cut groove,
14...Through hole, 16...Metal foil, 18...Back cover.

Claims (1)

[Claims] 1 A plurality of protrusions are integrally formed on at least one open end of the metal frame, while a V-cut groove is provided on the printed board along the open end of the metal frame, and the protrusion is provided in the V-cut groove. Providing a through hole to be inserted, and inserting the protruding piece into the through hole to connect the protruding piece protruding from the printed board and the metal foil provided on the printed board by soldering,
Thereafter, the printed board is split at the V-cut groove to remove the portion protruding from the metal frame, and a metal cover is provided on the one opening end so that the protrusion comes into contact with the inner surface of the shield case. Assembly method.