JPS5884498A - Structure for connecting circuit block - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a circuit block connection structure of an electric circuit suitable for use in a UHF band high frequency circuit.

The controller that converts UHF band radio waves to VHF band is
Usually, as shown in FIG. 13, a shield case is used, in which a case 41 made of a metal plate is divided by shield plates 42 to form several small chambers 43, and inside these small chambers 43, A circuit board 45 incorporating components 44 such as capacitors, resistors, transistors, etc. is housed and connected to a connecting terminal 46 passing through the shield plate 42 with a conductor wire 47 to electrically connect these circuit boards 45, or the case is closed. It has a structure in which it is electrically connected to the outside through a penetrating terminal. In addition, in order to prevent the Q from decreasing, the coil may be installed in a small room without using a circuit board and soldered directly to the nine terminals. The circuit board 45 can be attached to the case 41 by fixing the terminals 46 penetrating the metal case 41 and the shield plate 42 or by fixing the terminals 4B, which are placed upright in the case, by soldering, or by screwing them directly to the case.

In this way, conventional converters not only require time and effort to provide nine screws with terminals for attaching the circuit board and coil inside the case, but also are extremely troublesome to assemble the circuit board and coil. In addition, electrical connections between circuit boards are made by attaching connection terminals to the shield plate, which is difficult to assemble, resulting in a complicated structure and high cost.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a connection structure for circuit blocks of a high frequency electric circuit which has a simple structure and is easy to assemble.

Next, one embodiment of the present invention will be described in detail using the drawings.

A CATV converter is an example of a high frequency circuit in the UHF band. 1st W! The block circuit of the JK CATV converter is shown. The CATV converter extracts only the desired signal from the input high 4-frequency signal, converts it to an intermediate frequency signal, and outputs it.
It is a double converter type having two mixers, namely a first mixer 2 and a second mixer 8. To explain its operation, first, a high frequency signal is input from the input terminal IN, unnecessary signals are removed by the input filter 1, and the signal is input to the first mixer 2. #M local oscillator 5
is a variable frequency local oscillator that emits a local oscillator signal for a desired channel, and this local oscillator signal is amplified by a buffer amplifier 4 and input to the first mixer 2 . The first intermediate frequency signal 2 converts the first intermediate frequency signal into an input signal of a desired channel. The first intermediate frequency signal passes through an intermediate frequency signal filter formed by a helical filter 5, is amplified by an IF amplifier 6 in the next stage, and is then input to a second mixer 8. At the same time, the second local oscillator 7 converts the first intermediate frequency signal and inputs a local oscillator signal of a unique frequency to the second mixer 6 in order to make the signal equivalent to, for example, an empty TV channel. As a result, the second intermediate frequency signal generated by the second mixer 8 passes through the output filter 9 at the next stage and is output as only the empty channel signal of the TV.

FIG. 2 is an exploded perspective view for explaining the assembly structure of the CATV converter circuit. In the figure, 10 is a metal bottom plate, and this bottom plate 10 includes a strangling claw 1151 of the metal frame 11, a shark claw 12a of the shield I [12], a strangling claw 13 of the metal box-shaped shield case 15 & Reference numeral 611 is a frame body in which insertion holes 10a, . . . are formed, and the frame body 11 is divided into small chambers by a plurality of shield plates 12. 14, 15, 14, 17, 18.1
9 is a circuit block, which includes the input filter 1 shown in FIG.
The first mixer 2, the first station oscillator 5, etc. are made into blocks. After mounting the circuit blocks 14°i5, 16, 17, 18.19 on the bottom plate 10,
The frame body 11 is tightened with the tightening claws 11g, j2. Insert it into hole io6 and complete the assembly.

FIG. 5 is a cross-sectional view of the nine-circuit structure that has been assembled as described above, and FIG. 4 is a partially enlarged cross-sectional view of the nine-circuit structure. In the figure, reference numeral 20 denotes a seven-fold frame body of a circuit block in which each circuit block forms a desired section, and is made of synthetic resin or the like by molding. This mold frame 20
A protrusion 204 is integrally formed at the output end of the Kd, and a metal piece 21 serving as a round connection piece for connecting the circuit blocks is fitted and fixed in the protrusion 20&. As shown in FIG.
bl' (inserted and disposed. Metal piece 21 protruding outward from the protruding part ZOa of the mold frame 20 of the circuit block 14 divided by the frame 11 and the shield plate 12 and arranged in nine kotomi Above, the circuit block 15 of the adjacent small room
A metal piece 21 protruding outward from the mold frame 20 of
The circuit block 15 is arranged so that the metal piece 2
1 and the metal piece 21 are fixedly connected by forming a soldered part 25m. Reference numeral 22 denotes a ground terminal of the circuit block, which is fixedly inserted into the mold frame 20 and bent downward on the outside of the mold frame 20. This ground terminal 22 is formed on the bottom plate 10, inserted into the hole tOa, and fixed by forming a soldering portion 25b at the lower end. Between other circuit blocks 17.18 and circuit blocks 18.1
? The connections between the two are also done in almost the same way. Also, the mold frame 20
Metal piece 21 that becomes a connection conductor Metal piece 21 that becomes a wiring conductor
’ (see Figure 6). To explain the specific method of embedding the 9 connection conductors and wiring conductors, a metal plate is punched out using a press to form a pattern of connection conductors and wiring conductors. After forming the frame 20 by molding an insulating material such as synthetic resin on the pattern, removing unnecessary portions as connection conductors and wiring conductors allows connecting conductors to be formed in the molded body 20 made of an insulating frame made of synthetic resin or the like. Then, metal pieces 21, 21/, which will become wiring conductors, are embedded and fixed.

Next, the specific structure of the circuit block will be explained. 11
Figure g6 is a plan view showing the state before electrical components are placed on the mold frame 20 and fixed with soldering.
27. 27' is a coil made with an air core, and both ends thereof are provided with depressions 21'd as shown in Figs. 7 and 8. This will improve stability when placing each coil. 29 and 3
0 is a circuit board for high frequency circuits made of a ceramic plate.
It is placed on each wiring conductor 21'. Although not shown in Figure Ka, a wiring circuit in a pattern desired by the company is provided on the surface of the circuit board 29, 30, but the rounding is omitted to avoid complication of the drawing. A semicircular notch 29a is provided around each circuit board 29.50.

50& are released, and as shown in FIG. 9, these parts are coated with a metal coating 31 and provided with mounting terminal portions 31a.This mounting terminal portion 51a is connected to each circuit board 29. It is electrically connected to 30 wiring circuits. 32
and 33 a transistor mounted on the circuit board 29;
These are electrical components such as capacitors and resistors, and their terminals are provided on the circuit i29 and placed on the nine-wire circuit.

FIG. 10 is a partial cross-sectional view showing a state in which a circuit board 29 is placed and fixed with solder on the inter-circuit block connection metal piece 21 and ground terminal 22 which are placed and fixed in the molded frame 20 of the circuit block. be. Attachment of components on the circuit board and attachment of the circuit board and coil to the mold frame 20 are performed as follows. That is, as shown in FIG.
Terminal portion 511 with radius 511 portion K is mixed with paste and solder powder and dripped with solder 34 to adhere to terminal 35a of electrical component 33 and wiring circuit mounting terminal portion 31a, although not shown in the figure.・Drop reflow powder onto the contact area. Figure 9: Beam 70 - A cross-sectional view showing a good condition with the solder attached, the terminal part of the two-pronged coil, spider No. 1
2. As shown in Figure 2, solder is dropped 70. After that, electrical components are placed on this circuit block solder frame 20, and the assembly with reflow solder applied is heated in an electric furnace. When the reflow solder 34 is melted and cooled after death to visualize the solder, the circuit plastic molded frame 2 is formed.
The circuit block is completed by fixing each electrical component to 0 (.

As described above in detail, the present invention divides a frame into a plurality of small chambers using a plurality of shield plates having a substantially concave opening on one side, and arranges a circuit block in each of the small chambers. In the constructed high-frequency circuit, a metal piece connecting between circuit blocks is fitted and fixed into a protrusion formed integrally with the circuit block mold frame, and this protrusion is positioned in the concave opening of the shield plate. Place the circuit block on the bottom plate as shown in the figure below, and place the adjacent circuit block so that the metal piece embedded in the circuit block mold frame of the adjacent small chamber is close to the protruding metal piece, and the metal pieces are connected to each other. After soldering, the high-frequency circuit device is assembled by covering the shield plate with a partitioned frame, so all the circuit blocks can be installed on the bottom plate at once, making assembly easier. In addition to shortening the process and improving work efficiency, the cost is reduced by forming the connection piece between circuit blocks integrally with the circuit block mold frame, and the circuit block connection structure has excellent soldering reliability. can be provided.

[Brief explanation of drawings]

Fig. 1 is a block circuit diagram of a CATV converter, Fig. 2 is an exploded perspective view for explaining the assembled structure of a high frequency circuit according to the present invention, Fig. 3 is a sectional view of the assembled structure, and Fig. 4 is a circuit diagram. Fig. 5 is a partial perspective view showing the connection state of the circuit block mold frame protrusion and the shield plate, Fig. 6 is a partial cross-sectional view showing the connection state of the circuit block mold frame, and Fig. 6 shows various electrical components mounted on the circuit block frame. 7 is a cross-sectional view taken along the line B-B' in FIG. Figure, 1st
0, 11, and 12 are a partial perspective view and a partial sectional view showing the state of connection between the circuit board and the frame, and FIG. 1S is a schematic sectional view showing the state of connection between the conventional circuit boards. 1...Input filter, 2...1 day mixer, 3...
・First station oscillator, 4...Buffer amplifier, 5...Tocal filter, 6...IF amplifier, 7...Second
Local oscillator, 8... 2nd mixer, 9... Output filter, 10... Bottom plate, 11... Frame, 12...
Shield plate, 13... Shield case, 14-19.
...Circuit block, 20...Mold frame, 21,2
1/...Metal plate, 22...Earth terminal, 23-27
,271...Coil, 2? , 30...Ceraoc board, 31...Metal coating, st, ss...Circuit board, 3
4...S7a-Solder, 41...Case, 42...
・Shield plate, 45... Small chamber, 44... Parts, 45
...Circuit board, 46...Connection terminal, 47...Conductor, 48...Terminal 1□ Patent applicant: Alps Electric Co., Ltd. Representative Patent Attorney Sangai Tsuji (2 persons) Figure 12, 2nd, Figure 13 3

Claims (1)

[Claims] A plurality of circuit blocks are housed in small chambers of a nine-frame body divided by shield plates, and a plurality of shield plates having a substantially concave opening on the - side are fitted into the concave opening of the armpit shield plate. It consists of a plurality of circuit blocks having a frame made of an insulating material integrally formed with a protrusion, and the plurality of circuit blocks are connected by connecting metal pieces that serve as connection pieces embedded in the protrusion of the circuit block. A circuit block connection structure characterized by electrically connecting circuit blocks.