JPH0432747Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a variable condenser unit, and more particularly to a variable condenser unit included in a resonant unit for a modulator.

[Conventional technology]

A specific example of an RF modulator for European VCRs employing the PAL system will be shown below with reference to FIG. 6 as a specific example of electronic equipment using a variable condenser unit in the oscillation circuit section. In the figure, 1 is a chassis base, 2 is a main body board, and 3 is a resonant unit. The chassis base 1 has a rectangular frame body, and has an antenna input terminal 4 and a TV terminal 5 on one half of the upper opening, and a VTR terminal 6 and a feedthrough capacitor 7 on the side surface.
It has... The main body board 2 is a flat plate made of phenolic resin fitted into the chassis base 1, and a resonance unit 3 is attached to the surface thereof along with various electronic parts 8 and a switch 9. The resonance unit 3 is
As shown in FIG. 7, it consists of a resonant circuit including a variable capacitor VC, an inductance element _L1 , a disk capacitor _C1, etc., and is housed in a shield vest 10 shown in FIG. The shield base 10 is a metal case with an opening on the top surface, and a mounting tongue piece 10a on the bottom surface.
are formed integrally with the variable capacitor VC, and holes 10b for attaching the variable capacitor VC, lead extraction holes 10c, etc. are bored in the housing, and the variable capacitor VC and the variable capacitor VC each have a half volume inside the housing.
A glass printed circuit board 11 on which various electronic components are assembled is housed and fixed. Above variable capacitor
VC is a unit in which a stator S and a rotor R are housed in a U-shaped frame 12 that is open on three sides, as shown in FIG.
a, 12b and is movably fixed by a spring 13, and the stator S is attached to the back surface 1 of the frame 12.
2c through an insulating terminal plate 14, and electrically connected to the inductance element _L1 from the back side of the terminal plate 14. Also, the printed circuit board 11
are housed in the shield base 10, as shown in FIG.
When mounted on the PC board 11, the leads of the inductance element L2 and the power terminal 14 are led out from the printed circuit board 11 through the shield base ₁₀ and the main board 2 to the back side.

[The problem that the idea attempts to solve]

Incidentally, in the PAL type RF modulator described above, the resonance unit 3 is a variable capacitor VC unit housing a rotor R and a stator S in a frame 12, and a printed circuit board 11 on a shield base 10.
It is further attached to the main body board 2. Therefore, the variable capacitor VC is housed in a double frame, and the printed circuit boards on which the electronic components are assembled are also separated into one for the resonance unit and the other for the main body, which increases the number of parts and man-hours, and increases the number of assembly steps. The process also becomes complicated, leading to increased costs.

[Means to solve the problem]

This invention has a U-shaped frame with an opening on one side of the top and bottom, and is fixed inside the shield base, which has upper and lower holding frames partially installed in a bridge-like manner on the upper and lower openings, and is fixed on the lower holding frame and/or on the inner wall of the shield case. The stator is stacked on the mounted plate-shaped metallized capacitor and fixed by soldering, and the rotor is inserted between the upper and lower holding frames to be movable, and one lead of the inductance element is directly soldered to the stator of the variable capacitor unit. It is characterized in that it is fixed and housed in a shield base, and the resonant unit is directly soldered and fixed to the main body board.

[Effect]

According to the above technical means, the rotor and stator of the variable capacitor are assembled directly into the shield base of the U-shaped frame with openings on one side of the upper and lower sides, and attached to the main body board, and the surface of the main body board surrounded by the shield base. Then, assemble the electronic components of the resonant unit.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. Figures 1, 2, 3 and 4
The figures show a plan view, a front view, a side view, and a rear view of a variable converter unit 15 according to the present invention, and FIG. 5 shows a perspective view of a modulator 16 using the variable converter unit 15. 17 in Figures 1 and 2
is a shield base, R and S are the rotor and stator of the variable capacitor VC, and 18 is a plate-shaped metallized capacitor. The shield base 17 is a U-shaped frame with an opening on one side of the upper and lower sides, and upper and lower holding frames 17a and 17b are bridge-like on the upper and lower openings near the side opening, and a mounting tongue piece 17c is integrally formed on the periphery of the opening on the lower side. It is set in. Rotor R is upper and lower holding frame 17
It is inserted between a and 17b and is pivotally supported, and the rotor shaft portion is pressed from above and below by a spring 19 from the side opening side.
Contact and fix movably. The stator S is attached to the lower holding frame 17 with the blades loosely fitted to the rotor R.
b is fixed in a stacked state on the metallized capacitor 18. Therefore, metallized capacitor 1
8, the two electrodes are electrically connected to the lower holding frame 17b and the stator S, and the stator S is connected to the hot side of the variable capacitor VC shown in FIG.
The rotor R corresponds to the ground side, and the metallized capacitor 18 corresponds to the capacitor _C1 .
That is, Ronta R and stator S of the above variable capacitor VC
are the upper and lower holding frames 17a, 1 of the shield base 17.
7b and directly attached to the shield base 17.

Further, FIGS. 3 and 4 show the side and back sides of the shield base 17 shown in FIGS. 1 and 2 with the upper opening thereof closed with a lid 20.

Next, as a second embodiment, as shown in FIG. 1, an embossment S ₀ is formed on the back side of the stator S, and one end of the coil serving as the inductance element L ₁ is fitted into the embossment S ₀ and soldered. The other end is soldered and fixed to the back surface of the shield base 17 via the disk capacitor 21. Then,
The disc capacitor 21 corresponds to the capacitor _C2 of the resonant circuit shown in FIG. 7, and a resonant unit including an inductance element is formed within the variable capacitor unit 15. At this time, the stator S is eccentrically moved to the left in the figure, so that the inductance element _L1 is located approximately at the center within the shield base 17.

Furthermore, FIG. 5 shows a third embodiment in which the above resonance unit is used in a PAL type RF modulator.
In the figure, 22 is a chassis base, 23 is a main body board, and 24 is a resonant unit. The chassis base 22 has a substantially square frame body, and has an antenna input terminal 25 and a TV terminal 26 on the opening half of the top surface, and a VTR terminal 27 on the side surface. The main body board 23 is a flat plate made of the same glass material as the conventional printed circuit board 11 for the resonant unit fitted into the chassis base 22, and the resonant unit 24 is attached to the surface along with various electronic components 28 and switches 29, and furthermore, the resonant unit 24 is attached to the surface of the resonant unit 24 along with various electronic components 28 and switches 29. Connecting pins 30... are led out. Since the resonant unit 24 has an open bottom surface as described above, other electronic components housed within the resonant unit 24 can be directly incorporated into the surface of the main body board 23 except for the power terminal, and assembly is simplified. In addition, since the printed circuit board for the resonant unit is integrated with the main body board 23, the electronic components are shielded by the main body board 23 and the shield base 17, and the shielding performance is improved.

[Effect of idea]

According to the present invention, since the resonant unit is formed by directly providing the variable capacitor unit on the shield base, the number of parts and man-hours are reduced, productivity is improved, and costs can be reduced. Furthermore, when the above-mentioned resonant unit is used in a modulator, the printed circuit board inside the unit can be integrated with the main circuit board, which facilitates assembly and improves shielding performance, which also reduces costs and improves characteristics. be able to.

[Brief explanation of drawings]

1 to 4 are a plan view, a front view, a side view, and a rear view showing an embodiment of a variable condenser unit according to the present invention, and FIG. 1 also shows a plan view of a resonant unit according to the present invention. FIG. 5 is a perspective view showing an embodiment of the modulator according to the present invention, and FIG.
A perspective view showing a specific example of a PAL type modulator, FIG. 7 is a circuit diagram of the resonant circuit of the modulator shown in FIG. 6, and FIG. 8 is a side view of the variable condenser unit of the resonant unit of the modulator shown in FIG. FIG. 9 is a partially exploded perspective view and a side sectional view of the main part of the resonant unit shown in FIG. 8. 15...Varicon unit, 16...Modulator, 17...Shield base, 17a, 17b
...Upper and lower holding frame, 18...Metallized capacitor, 24...Resonance unit, R...Rotor, S...
...Stator.

Claims (1)

[Claims for Utility Model Registration] (1) Upper and lower holding frames are bridged over the opening of the U-shaped shield base, and a rotor is movably attached between the upper and lower holding frames, and A variable capacitor unit characterized by stacking a stator on a plate-shaped metallized capacitor fixed on the inner wall of a shield base and fixing it by soldering. (2) A resonant unit characterized in that one end of an inductance element is directly connected to the stator of the variable capacitor unit according to claim (1) and housed within the shield base. (3) A modulator characterized in that the resonance unit according to claim (2) is directly fixed to a main body substrate by soldering.