JP3411461B2 - Tuner structure and tuner for cable modem using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates generally to relate front end of the internal high-frequency portion of the transceiver of television broadcasting called <br/> a tuner, particularly using the same structure and thin tuner cable Regarding tuners for modems.

[0002]

2. Description of the Related Art In Japan, the United States and other countries, an input connector called an F-type connector (or F plug) is used, which is shown in FIG. In FIG. 9, the F-type connector 1
The outer diameter of the threaded portion 121 is 9.4 mm.
φ, the outer diameter 122 of the contact surface to the chassis surface is 11.0 mmφ
Is prescribed. Therefore, it is difficult to obtain a tuner structure having an outer diameter 121 of the contact surface of the F-type connector with the chassis surface that is thinner than 11.0 mmφ.

FIG. 10 shows a conventional F-type connector tuner structure, which includes an input connector 120, upper and lower shield covers 123, a feedthrough capacitor 124, and a chassis angle 1.
25. Assuming that the thickness of the chassis angle is C and the thickness of the tuner is D, as shown in FIG.
Outer diameter of the contact surface of the type connector to the chassis surface: 11.0 mm
φ) <(thickness of chassis angle: C) <(thickness of tuner: D).

As an example, specifically, C = 12.3 m
m to 12.9 mm and D = 14.0 mm to 17.0 mm. The thickness (C) of the chassis angle is designed to be larger than the outer diameter of the input connector in order to secure the mounting strength of the input connector. Since a relatively thick coaxial cable is usually connected to the input connector, the chassis angle is deformed when the mechanical strength is weak. Furthermore, in order to secure the strength of the shield lid itself and to ensure that the internal shield plate (partition plate) of the chassis angle and the shield lid are in contact with each other via the claws, drawing processing (bulging of the shield lid, etc.) is required. Therefore, the thickness of the diaphragm is required. Therefore, the thickness of the tuner structure was considerably thicker than that of the input connector.

[0005]

The conventional tuner structure and the cable modem tuner using the tuner structure have the following problems.

1) Miniaturization of Tuner Structure Shape Tuner Shape Miniaturization Since a cable modem is an accessory to a personal computer, miniaturization is required, and the tuner shape becomes a problem.

2) Improvement of chassis strength of tuner structure An F type plug is used for an input terminal of a cable modem. Since a load of 20 kg or more is applied to the F plug when connecting the coaxial cable, the chassis to which the tuner input terminal is fixed is required to have strength.

3) Improvement of shield effect of tuner for cable modem The tuner for cable modem is connected to the cable line as a CATV device, but avoids the influence of spurious interference to other devices (for example, a set top converter). There must be. Therefore, it is necessary to improve the spurious level at the input terminal as compared with the conventional TV tuner.

Further, the tuner for the additional cable modem of the duplexer circuit transfers data bidirectionally, but the conventional TV tuner does not have the function of mixing the upstream signals, so that the duplexer function needs to be added. Moreover, the shield of the filter by the addition of this circuit is required.

Further, the cable modem tuner is an accessory device of a personal computer, and is mostly installed in the vicinity. Since cable modems are often exposed to digital noise from personal computers, it is necessary to take measures against inflow interference signals.

[0011]

A tuner structure according to claim 1 of the present invention is a circuit board on which an electronic circuit element such as a transistor, a resistor or a feedthrough capacitor is mounted, a chassis angle, a shield lid, and an input. in the structure of a tuner and a connector, the outer diameter of the contact surface of the chassis of the input connector, than a thickness of the chassis angle
Greater relationship near is, the mounting said input connector
On the chassis short side of the chassis angle, the chassis short side
Of the surface of the chassis and the outer periphery of the short side surface of the chassis.
An outer drawing portion is provided, and the protruding drawing portion is
Shaped into an arc shape with respect to the hole for inserting the input connector.
It is made and has two corners from the arc shape.
It is characterized in that it is formed in a π type shape .

According to a second aspect of the present invention, there is provided a tuner structure, which includes a transistor, a resistor, a feedthrough capacitor and the like.
Circuit board with child circuit elements and chassis angle
Of a tuner having a shield lid and an input connector
In the structure, the contact surface of the input connector to the chassis
Has a larger outer diameter than the thickness of the chassis angle.
And push it to the side of the chassis angle of the chassis angle.
Disposing the drawing-in processing part and the pressing claw part,
The circuit board is sandwiched between the narrow drawing section and the pushing claw section.
And has a mechanism for
It is characterized in that an umbilicus-shaped protruding portion is provided.

A cable model according to claim 3 of the present invention.
The tuner for dem is the tuner according to claim 1 or 2.
In a tuner for a cable modem having the structure of
High-frequency amplification input circuits with different bands and high-frequency amplification
Unit, high frequency amplification output circuit, frequency conversion circuit and local oscillator
Vibration circuit, intermediate frequency amplification circuit, SAW filter and
And after-amplifier circuit (IF amplifier circuit) and PLL tuning times
It is characterized by including a road .

[0014]

1 to 8 are views relating to an embodiment of the present invention and will be described with reference to the drawings. FIG. 3 is a development view of a tuner structure according to an embodiment of the present invention. The metal integrated plate 10 for chassis housing of FIG.
It is composed of five regions, one short chassis side 11 and 12, two long chassis sides 13 and 14, and a chassis angle center plane 15. The shaded area is an area that is punched out by press working. From a single metal flat plate (about 0.6 mm thick) to a metal integrated plate 1 for chassis housing
0 is pressed, drawn, extruded, bent, etc. to form a rectangular parallelepiped tuner structure of the present invention.

The chassis short side surface 11 will be described. The chassis short side surface 11 is a surface to which the input connector is attached, 16 is a hole for inserting the input connector (F-type connector or F plug), and 17 and 18 are protruding drawing processing parts. It is extruded and drawn so as to be pressed into a plane (that is, in a shape protruding in the rearward direction with respect to the paper surface). On the contrary, when projecting to a shape that protrudes from the plane of the short side surface of the chassis (that is, a shape that projects in the front direction with respect to the paper surface), when tightening with the flange of the F type connector clamped, tightening It has a structure that avoids hitting the jig and making it impossible to perform sufficient tightening. Also,
The protruding drawing parts 17 and 18 are formed in an arc shape with respect to the hole of the input connector and have a shape that increases the mechanical strength. Furthermore, the protruding drawing part 17 has two arc shapes. A π (pi) shape with an angle is adopted, and the shape further increases the mechanical strength. The protrusion drawing processing portion 18 has a short arc shape due to space limitation, but it is of course possible to make it the same π (pie) shape as 17.

Two outer edges 19 of the hole 16 into which the F-type connector is inserted are outer drawn portions, which are bent backward in the plane of the drawing and are drawn on the shoulders thereof. It is a place. As will be described later, the arrangement of the outer drawing portion 19 and the protruding drawing portions 17 and 18 has the function of increasing the mechanical strength of the chassis.

The punching portion 20 and the pushing claw portion 21 on the right hand side of the hole 16 into which the F-type connector is inserted serve to hold the circuit board with the pushing drawing processing portions 22 on both sides thereof. An umbilicus-shaped protruding portion (about 0.8 mmφ) 23 in the center of the push-in claw portion 21 functions to suppress the flow of solder. Further, the punching wire 24 on the upper part of the pushing claw portion 21 is a wire punched with a die having almost zero clearance.

Further, the punching portions 25 and 26 at both ends of the chassis short side surface 11 are the fitting protrusions 27 of the chassis long side surfaces 13 and 14 in the assembly of the tuner structure.
28 for fitting and forming a rectangular tuner structure by twisting. Further, on the other short side surface 12 of the chassis, there are two pushing claw portions 29, a pushing drawing portion 30, and two punching portions 31 and 32.
The same operation as described above is performed.

Next, the long side surface 14 of the chassis will be described. The long side surface 14 of the chassis serves as a sheathed case, and is provided with a push-in claw portion and a push-drawing processing portion for holding the circuit board, which serves to hold the circuit board. Explaining according to the drawing, the punching portion 33 and the pushing claw portion 34 have a function of holding the circuit board with the pushing drawing processing portions 35 on both sides thereof. Umbilical protrusion at the center of the push-in claw 34 (about 0.8 mmφ)
36 functions to suppress the flow of solder. Further, the punching wire 37 on the upper part of the pushing claw portion 34 is a wire punched with a die having almost zero clearance. For details of the operation of holding the circuit board on the long side surface 14 of the chassis, see FIG.
I will explain later.

Next, the chassis angle center surface 15 will be described. The chassis angle center surface 15 has nine holes for inserting feedthrough capacitors, and the chassis short side 1
There are three partition plates arranged in parallel with 1 and 12, and one partition plate also arranged vertically, which will be described in detail with reference to FIGS. 2, 6, 7, and 8. To do.

A rectangular parallelepiped is formed by processing the metal integrated plate 10 for chassis housing of FIG. 3, which is a development view of the structure of the tuner according to one embodiment of the present invention, by pressing, drawing, protruding drawing, bending, etc. 2 and FIG. 1 show the structure of the tuner of the present invention. 2 is a chassis angle of the tuner structure of the present invention.
2A is a side view of the chassis short side surface 11, FIG. 2B is a top view, FIG. 2C is a side view of the chassis long side surface 13, and FIG.
FIG. 3D is a side view of the short side surface 12 of the chassis. In FIG. 2, an F-type connector (or F plug) that is an input connector
Is not attached yet. 1 is an external view of the tuner structure of the present invention, in which an F-type connector and a shield cover are attached. 1 (a) is a top view, FIG.
1B is a side view on the long side, and FIG. 1C is a side view on the short side.

In addition, in FIG. 3, five regions, that is, two chassis short side faces 11 and 12, two chassis long side faces 13 and 14 and a chassis angle center face 15 are created from the chassis housing metal integrated plate 10. Therefore, each side plate and the center surface of the chassis angle are mechanically connected to each other, so that a tuner structure having high productivity and high mechanical accuracy can be obtained.

In the side view which is the chassis short side surface 11 of FIG. 2A, 16 is a hole for inserting an input connector (F type connector or F connector), and 17 and 18 are protrusion drawing portions. The protrusion is drawn so as to be pressed into the plane of the short side surface of the chassis (that is, the shape protruding in the rearward direction with respect to the paper surface). In addition, two 1s which are both outer edges of the hole 16 for inserting the F-type connector
Reference numeral 9 denotes an outer drawing portion, which is bent rearward with respect to the paper surface and has a shoulder portion 19a.
Reference numeral 20 is a punching portion, 21 is a pushing claw portion, and 22 is a pushing drawing portion, which is a drawing portion that is pushed into the plane of the long side surface of the chassis (that is, a shape that projects backward in the plane of the drawing). Has been done. Reference numeral 23 is an umbilicus-shaped protruding portion at the center of the push-in claw portion 21, reference numeral 24 is a punched wire, and reference numeral 24 is a wire punched with a die having almost zero clearance. Numerals 25 and 26 are punched portions, which are formed by fitting the fitting protrusions 27 and 28 of the long side surfaces 13 and 14 of the chassis and by twisting to form a rectangular tuner structure. Numerals 38 and 39 are protrusions for hooking and fixing the upper and lower shield lids, and they are protruded and drawn in a shape protruding toward the plane of the chassis short side surface (that is, a shape protruding in the front direction with respect to the paper surface). Has been done.

Next, the top view of FIG. 2B is an assembly surface of the chassis angle center surface 15. The structure of the tuner according to the present invention comprises two chassis short sides 11 and 12.
And the two long sides 13 and 14 of the chassis form four outer surfaces, and three partition plates 40, 41 and 42 arranged in parallel with the short sides 11 and 12 of the chassis are also vertical. There is one partition plate 43 arranged in
Reference numeral 4 denotes a bridge portion having a shield effect, and has nine holes 45 into which the feedthrough capacitors are inserted. Also, 19 is F
It is an outer drawing portion formed on both outer edges of the hole 16 into which the mold connector is inserted, and the shoulder portion is formed with the drawing processing 19a. In addition, 27, 28 of the chassis short side surface 11
Is a protrusion that forms a rectangular parallelepiped tuner structure by twisting (the same applies to the other chassis short side surfaces 12).

Next, in the side view of the long side surface 14 of the chassis of FIG. 2 (c), 33 is a punching portion, 34 is a pushing claw portion, and 35 is a pushing drawing processing portion, which is relative to the plane of the long side surface of the chassis. It is extruded in a pressed-in shape (that is, a shape protruding in a direction backward with respect to the paper surface). Reference numeral 36 denotes an umbilicus-shaped protruding portion at the center of the pushing claw portion 34, and reference numeral 37 denotes a punching line punched with a die having almost zero clearance. 28 and 32 are fitting protrusions,
The structure of a rectangular parallelepiped tuner is formed by twisting. Reference numerals 46 and 47 are projections for hooking and fixing the upper and lower shield lids, and projecting to a shape protruding toward the plane of the short side surface of the chassis (that is, a shape projecting forward with respect to the paper surface). Has been done.

Furthermore, the chassis short side 12 of FIG.
The side view is the chassis short side 1 of FIG.
The side view of No. 1 is almost the same as the side view except the mounting portion of the input connector. In FIG. 2D, there are two pushing claw portions 29, a pushing drawing processing portion 30 and two punching portions 31 and 32, and the same operation as described above is performed. Further, 48 and 49 are projections for hooking and fixing the upper and lower shield lids, and projecting in a shape projecting with respect to the plane of the chassis short side surface (that is, a shape projecting forward with respect to the paper surface). It is drawn.

FIG. 1 is an external view of a tuner structure according to an embodiment of the present invention, in which an F-type connector and a shield lid are attached. 1 (a) is a top view, FIG.
1B is a side view on the long side, and FIG. 1C is a side view on the short side.

In the top view of FIG. 1 (a), 19 is an outer drawing portion of both outer edges of the hole 16 into which the F-type connector is inserted, and 50 is an F-type connector (or F plug). , 51 is an upper shield lid, and 52 is a shield lid 5.
It is a cutout portion of 1. As shown in FIG. 1 (a),
The notch portion 52 is configured to abut the outer drawing portion 19, thereby realizing a thin tuner structure having an outer shape that does not exceed the protruding height of the outer drawing portion 19. . The outer drawing portion 19 and the protruding drawing portions 17 and 18 already described increase the mechanical strength of the structure of the tuner, while the cutout portion 52 of the shield lid 51 is used to reduce the thickness of the tuner. The structure is realized. In this way, the contradictory elements are skillfully overcome. The shield lid 51 includes the protrusions 38, 3 on the chassis long side surface and the chassis short side surface described in FIG.
It is fixed to the chassis with a structure that hooks with 9, 46, 47, 48, 49, etc.

Next, in the side view of the long side of FIG. 1B, 19 is an outer drawing portion, 50 is an F type connector (or F plug), 51 is an upper shield lid, and 52 is a shield lid 5.
1 is a notch portion, 53 is a lower shield lid, 54 is a notch portion of the shield lid 53, 55 is a leg for attaching a tuner structure, and 56 is a terminal rod of a feedthrough capacitor. Although not shown, the notch 54 of the lower shield lid 53 has the same shape as the notch 52 of the upper shield lid 51 described with reference to FIG. The cutout portion 54 of the lower shield lid 53 is configured to abut the outer drawn portion 19, so that the structure of the thin tuner has an outer shape that does not exceed the protruding height of the outer drawn portion 19. The body is realized.

Further, in the side view of the short side of FIG. 1 (c), reference numerals 17 and 18 denote an extruded drawing portion, 19 an outer drawn portion, 50 an F type connector (or F plug), 27,
Reference numeral 28 is a twisted fitting projection, 51 is an upper shield lid, 53 is a lower shield lid, 55 is a leg for attaching a structure of a tuner, and 56 is a terminal rod of a feedthrough capacitor. In addition, the protrusion drawing portions 17 and 18 are formed by being pressed into the plane of the short side surface of the chassis (that is, the shape protruding toward the rear side with respect to the paper surface). The extruded drawn portions 17 and 18 are formed in a substantially arcuate shape with respect to the outer circumferential circle of the F-type connector, and have a shape that increases the mechanical strength. 2 horns from π
The (pie) shape is adopted, and the shape further increases the mechanical strength.

In FIG. 1 (c), when the diameter of the contact surface of the F type connector (input connector or F connector) to the chassis is A and the thickness of the chassis angle is B, the cable modem to which the present invention is applied In the tuner, A = 11.0m
m (standard value), B = about 9.2 mm, and the tuner structure has a relationship of A> B. The value of B of the thickness of the chassis angle is generally B = 8.8 mm to 9.6 mm
It is a degree. At this time, the thickness of one metallic flat plate forming the tuner structure is about 0.6 mm. Also, the outer shape of the threaded portion of the F-type connector is about 9.3 mmφ,
The thickness of the chassis angle of the tuner structure to which the present invention is applied can be about 9.2 mmφ, which is smaller than the outer shape of the threaded portion of the F-type connector.

After all, an example of the outer shape of the tuner for a cable modem to which the present invention is applied is about 11.5 mm × about 7 excluding the protruding portion (about 14.5 mm) of the F-type connector.
The resulting structure was a flat tuner having a size of about 0.2 mm × about 32.2 mm. The height of the tuner structure is about 11.5 m
m and the diameter of the contact surface of the F-type connector to the chassis 11.0m
About 0.5 mm larger than m is due to factors such as the thickness of the metallic flat plate and the bulge of the shield lid.

Next, the mounting structure of the circuit board to the tuner structure will be described. FIG. 4 is a diagram illustrating mounting on the circuit board on the long side surface 14 (or 13) of the chassis in FIG. 4A is a view seen from the long side surface 13 of the chassis, FIG. 4B is a sectional view thereof, and FIG. 4C is a top view thereof.

In FIG. 4A, the chip capacitor,
The circuit board 57 on which electronic circuit elements such as chip resistors, semiconductors, diodes, ICs, coils and feedthrough capacitors are mounted is shown by hatching. The punching portion 33 and the pushing claw portion 34 serve to hold the circuit board 57 with the pushing drawing processing portions 35 on both sides thereof. The umbilicus-shaped protrusion 36 at the center of the push-in claw portion 34 functions to suppress the flow of solder. Further, the punching wire 37 on the upper part of the pushing claw portion 34 is a wire punched with a die having almost zero clearance. The bridge portion 58 on the long side of the chassis above the punched line 37 serves to increase the mechanical strength of the tuner structure. Reference numeral 46 is a protrusion for hooking and fixing the upper shield lid. Further, the punching portion 33 has a width of about 1 mm, and the pushing claw portion 34 (width of about 2 mm
The circuit board 57 is softly clamped.

In FIG. 4 (b), the circuit board 57 has a pushing claw portion 34 and an umbilicus-shaped projecting portion (about 0.8 mmφ) 36 at the center of the pushing claw portion 34 serves to take a lot of fillets of the solder 59 by reflow. Make up. Reference numeral 14 is a long side surface of the chassis, 35 is a pressed drawing portion, 37 is a punching line, and 58 is a bridge portion. The circuit board 57 does not contact the long side surface 14 of the chassis, but is sandwiched with a gap 60. This serves as a buffer function for preventing impact or distortion due to thermal or mechanical factors from directly acting on the circuit board 57.

In FIG. 4C, 14 is a chassis long side surface, 34 is a pushing claw portion, 57 is a circuit board, and 60 is a gap between the chassis long side surface 14 and the circuit board 57.

5A and 5B are views for explaining the mounting structure and caulking of the F-type connector, FIG. 5A is a mounting structure diagram of the F-type connector, and FIG. 5B is for explaining the caulking of the F-type connector. 5C is an enlarged view of FIG. 5B.

FIG. 5 (a) is a view for explaining the mounting structure of the F-type connector. 11 is a short side surface of the chassis, 19 is an outer drawing portion, 50 is an F-type connector, 57 is a circuit board, and 61 is an F-type. The center pin 62 of the connector is a dielectric insulator surrounding the center pin 61 of the F-type connector, and input / output of electric signals is performed via the center pin 61 connected to the circuit board 57.

FIG. 5B is a view for explaining the crimping of the F-type connector, and is a view of the F-type connector as seen from the back side. Reference numeral 19 is an outer drawn portion, 57 is a circuit board, 61 is a center pin of an F-type connector, 62 is a dielectric insulator surrounding the center pin 61 of the F-type connector, and 63 is a caulking brim (F-type connector) of the F-type connector. Shell), 64 is a caulking mark, and 65 is a caulking mark.

FIG. 5 (c) is an enlarged view of FIG. 5 (b),
57 is a circuit board, 61 is a center pin of an F-type connector,
62 is a dielectric insulator surrounding the center pin 61 of the F-type connector, 63 is a brim of the crimp of the F-type connector, 64 is a caulking mark, and 65 is a crack of the caulking mark. Crimping collar 6
Since 3 is generally nickel-plated, solder paste is poor. However, the caulking marks 64 are exposed from the brass material of the base material, and the wettability of the solder is improved. The caulking trace crack 65 serves as a suction port for the solder at the time of solder dipping, serves as a water channel for supplying the sucked solder to the caulking trace 64, and sufficiently supplies the caulking trace 64 with the solder. In the conventional caulking method, the four corners of the brim of the caulking are crimped, whereas the caulking trace 64 according to the embodiment of the present invention is caulked circumferentially along the brim of the caulking, and Combined with the action of the cracks 65, the rotational strength has been improved to three times or more (about 30 kg · cm) as compared with the conventional one.

FIG. 6 is a view for explaining the mounting structure of the feedthrough capacitor, in which the feedthrough capacitor 58 is inserted into the feedthrough capacitor hole 45 on the long side surface 14 of the chassis. 57 is a circuit board, 66 is a capacitor, 67 is a chip component, 68 is a coil component, 53 is a lower shield lid, 5
6 is a terminal rod of the feedthrough capacitor. As shown in FIG. 6, the feedthrough capacitor has a mechanism to be attached from the inside of the chassis angle (chassis long side surface 14 or the like).
In the conventional example, it is inserted from the outside of the chassis, whereas in the present invention, it is inserted from the inside. By adopting this mounting structure, flux, cream solder, etc. do not flow out during reflow soldering, and contact failure between the shield lid and the chassis can be prevented. The circuit board on which the components are mounted and wired is inserted into the chassis, the claws of the push-in claw portions 34 (not shown) are projected, and after assembly, the secondary solder dip is performed to complete the process. When the feedthrough capacitor is attached in the opposite direction, the solder flux spreads on the contact surface between the flange of the feedthrough capacitor and the chassis angle, and the solder flux interferes with the contact surface 14a between the flange 58a of the feedthrough capacitor and the chassis angle. This is because there is a case where the solder does not flow to the interface.

Next, FIG. 7 is a view for explaining the shape of the partition plate of the tuner structure at the assembly surface of the chassis angle center surface 15 described in the top view of FIG. 2B. 7A is a diagram for explaining only the shape of the partition plate, and FIG. 7B is a diagram for explaining the relationship between the shape of the partition plate and the circuit board. 40 and 4 in FIG.
Reference numerals 1 and 42 show the shapes of the respective partition plates, and FIG.
FIG. 7B is a diagram for explaining the relationship with the circuit board 57. An appropriate partition plate shape is selected according to the degree of electrical shielding and electrical wiring.

In the description of FIG. 1 to FIG. 7, two chassis short side faces 1 are formed from the chassis housing metal integrated plate 10 shown in FIG.
Although five regions of 1, 12 and two long side surfaces 13 and 14 of the chassis and the central surface 15 of the chassis angle are created, the invention is not limited to the case of being made only from the metal integrated plate for chassis housing. Chassis short side 11
And a chassis short side 12 and two chassis long sides 1
Of course, the structure of the tuner may be created from three plates 3, 14 and the chassis angle center plane 15.

FIG. 8 shows an example of a cable modem tuner according to an embodiment of the present invention. Figure 8
FIG. 8A is a block diagram of an electric circuit, and FIG. 8B is a diagram illustrating the relationship between the block diagram of the electric circuit and a tuner structure.

In the block diagram of the electric circuit of FIG. 8A, the CATV input signal is input terminal (F type connector) 70.
After passing through a high-pass filter (HPF or IF filter) 71 which is introduced into the input signal switching circuit 72, 73, 74, it enters the input signal switching circuits 72, 73, 74. The tuner for cable modem is 470-860MHz
Receive UHF band (B3 band), 170MHz
VHF High band (B receiving ~ 470 MHz
2 bands), VHF L receiving 54-170 MHz
It is divided into an ow band (B1 band) and is composed of a receiving circuit for each band. Input signal switching circuits 72, 73,
74 are for B1 band, for B2 band, and for B3 band, respectively. The CATV signal divided into each band is
After tuning to a desired signal in the high-frequency amplification input tuning circuits 75, 76, 77, it is amplified in the high-frequency amplifiers 78, 79, 80, and passed through the high-frequency amplification output tuning circuits 81, 82, 83 to generate a local oscillation circuit (parallel type local (Oscillation circuit) 85, 87, 89 and mixing circuits 84, 86, 88 convert the signal to an intermediate frequency signal, which is led to an IF amplifier circuit 90, and an output terminal 9 via a SAW filter circuit 91 and an IF filter circuit 92.
3 is output. Further, 94 is an AGC terminal.

The data signal input from the data terminal 95 is connected to the CATV input terminal 70 through the upstream circuit 96.

In the diagram for explaining the relationship between the block diagram of the electric circuit of FIG. 8B and the structure of the tuner, the input connector 50 is the input terminal 70 for the CATV input signal, the short side surface 11 of the chassis and the partition plate 40. A high-pass filter 71 and an upstream circuit 96 are provided between
One feedthrough capacitor is assigned to the data terminal 95.

Next, between the partition plates 40 and 41, 7
2, 73, 74 input signal switching circuits and 75, 7
6, 77 high frequency amplification input tuning circuits are provided. One feedthrough capacitor is assigned to the AGC terminal 94.

Next, a high frequency amplification output tuning circuit 81, a high frequency amplification output tuning circuit 82, and a high frequency amplification output tuning circuit 83 are arranged between the partition plate 41 and the bridge 44.

Further, mixing circuits 84, 86, 88 and local oscillation circuits 85, 87 are provided between the partition plate 42, the partition plate 43, the chassis short side surface 12 and the chassis long side surface 13.
89 is provided.

Further, between the partition plate 42, the partition plate 43, the chassis short side surface 12 and the chassis long side surface 14,
IF amplifier circuit 90, SAW filter circuit 91 and IF
A filter circuit 92 is provided and one feedthrough capacitor is assigned to the output terminal 93. Improvement of spurious in the input terminal and duplexer by applying the appropriate partition plates 40, 41, 42, 43, the circuit design / circuit arrangement, and the structure of the tuner of the present invention as described in FIG. Electrical improvements such as the addition of circuits and countermeasures against inflow interference signals (noise resistance) are performed. For each effect,
To further explain, 1) the spurious level of the input terminal of the present invention is improved by 10 dB to 20 dB compared with the level of the conventional input terminal spurious, and VHF B
Numerical effects of -35 dBmV or less for AND and -30 dBmV or less for UHF BAND were confirmed.

2) Although a signal of +50 dBmV to +60 dBmV is applied to the additional data terminal of the duplexer circuit, it is easy to inductively couple to the high frequency amplification input tuning circuit inside the tuner, but in the present invention, -Rudder plate 40
(See FIG. 7A and FIG. 8A), this problem is solved.

3) Inflow noise (countermeasure against inflow interference signal) In the present invention, power supply terminal 97, data terminal 95, AGC
Since the feedthrough capacitors are used for the (PLL control) terminal 94 and the output terminal 93, it is possible to reduce inflow noise to each terminal, for example, high frequency noise such as SW power supply noise and digital noise.

Improvement of Shielding Effect of Cable Modem Tuner Although a cable modem tuner is connected to a cable line as a CATV device, it must be affected by spurious interference to other devices (eg, set-top converter). I won't. For this reason, it is necessary to improve the level of spurious at the input terminal as compared with the conventional TV tuner, but as described above, the tuner structure according to the embodiment of the present invention has a measure against spurious interference. Is enough.

Further, the tuner for the additional cable modem of the duplexer circuit transfers data bidirectionally, but the conventional TV tuner does not have the function of mixing the upstream signals and the addition of the duplexer function is necessary. However, the shield of the filter is required by adding this circuit, but as described above, the addition of the duplexer circuit is sufficient in the structure of the tuner according to the embodiment of the present invention.

Further, the cable modem tuner is an accessory device of a personal computer, and is mostly installed in the vicinity. In many cases, cable modems are exposed to digital noise from a personal computer, so countermeasures against inflow interference signals are necessary. However, as described above, in the tuner structure according to one embodiment of the present invention, inflow interference resistance signals are used. Signal measures are sufficient.

[0057]

As described above, according to the tuner structure of the first aspect of the present invention, the circuit board on which the electronic circuit element such as the transistor, the resistor and the feedthrough capacitor is mounted, the chassis angle, and the shield cover. When, in the structure of a tuner having an input connector, an outer diameter of contact surface of the chassis of the input connector, the thickness of the chassis angle
Greater relationship near than is, mounting the input connector
On the short side of the chassis of the chassis angle
Extrusion drawing part on the short side and outside of the chassis short side
With the outer drawing part on the periphery, the protruding drawing process
The part has a circular arc shape with respect to the hole for inserting the input connector.
In addition to being formed in a shape, two corners are formed from the arc shape.
The chassis angle is smaller than the outer shape of the contact surface of the F type connector with the chassis, and the chassis strength is large (about 20 kg · cm). Above) we could obtain the tuner structure.

According to the tuner structure of claim 2 of the present invention, a transistor, a resistor, and a feedthrough capacitor are provided.
Circuit board with electronic circuit elements such as
A tube having a guru, a shield lid, and an input connector.
The structure of the input connector to the chassis of the input connector
The outer diameter of the contact surface is larger than the thickness of the chassis angle.
The long side of the chassis of the chassis angle
The push-in drawing part and the push-in claw part are arranged in the
The circuit board is formed by the embossing processing section and the pushing claw section.
It has a mechanism to hold it,
Characterized by having an umbilicus-shaped protrusion in the center
The chassis angle of the F-type connector is
To obtain a tuner structure that is smaller than the outer shape of the contact surface to the chassis
I was able to

The circuit board is brought into contact with the side surface of the chassis.
Instead, it has a structure in which it is sandwiched with a certain gap, and
Impact or distortion due to mechanical factors directly affects the circuit board
It is possible to obtain a tuner structure that prevents the above.
In addition, the umbilicus-shaped protrusion can suppress the flow of solder.
And take a lot of solder fillet by reflow
be able to.

A cable model according to claim 3 of the present invention.
According to the tuner for a dem, the cheek according to claim 1 or 2.
For tuners for cable modems that have a tuner structure
And multiple high-frequency amplifier input circuits with different bands and high frequency
Wave amplifier, high frequency amplification output circuit, frequency conversion circuit
Local oscillator circuit, intermediate frequency amplifier circuit, SAW fill
And after-amplifier circuit (IF amplifier circuit) and PLL
It is characterized by including a tuning circuit,
Improvement of spurious in child, addition of duplexer circuit
In addition, electrical measures such as countermeasures against inflow interference signals (noise resistance)
The improvement is sufficient.

[Brief description of drawings]

FIG. 1 is an external view of a tuner structure according to an embodiment of the present invention, in which an F-type connector and a shield lid are attached, (a) is a top view, and (b) is a long side. It is a side view of the side, (c) is a side view of the short side.

FIG. 2 is a view showing an assembled chassis angle of the tuner structure of the present invention, (a) is a side view of the chassis short side surface 11, (b) is a top view, and a chassis angle center surface. 15C is an assembly surface of 15, and FIG.

FIG. 3 is a development view of a tuner structure according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a mounting structure of the circuit board to the structure of the tuner according to the embodiment of the present invention;
(A) is the figure seen from the long side 13 of the chassis, (b)
Is a sectional view thereof, and (c) is a top view.

FIG. 5 is a diagram for explaining a mounting structure and caulking of the F-type connector to the structure of the tuner according to the embodiment of the present invention, FIG. 5A is a mounting structure diagram of the F-type connector, (B) is a figure for demonstrating the crimping of an F-type connector, (c) is an enlarged view of (b).

FIG. 6 is a diagram for explaining a mounting structure of the feedthrough capacitor to the structure of the tuner according to the embodiment of the present invention.

FIG. 7 is a diagram for explaining the shape of the partition plate of the tuner structure at the assembly surface of the chassis angle center surface 15 of the tuner structure according to the embodiment of the present invention, and FIG. It is a figure for demonstrating only the shape of a partition board, (b) is a figure for demonstrating the relationship between the shape of a partition board, and a circuit board.

FIG. 8 shows an example of a tuner for a cable modem to which a tuner structure according to an embodiment of the present invention is applied, in which (a) is a block diagram of an electric circuit and (b) is a block diagram of an electric circuit.
FIG. 3 is a diagram illustrating a relationship between a block diagram of an electric circuit and a tuner structure.

FIG. 9 is a schematic perspective view of an F-type connector.

FIG. 10 is an external view of a structure of a tuner using a conventional F-type connector.

[Explanation of symbols]

10 Metallic Integrated Plate for Chassis Housing 11 Short Sides of Chassis 12 Short Sides of Chassis 13 Long Sides of Chassis 14 Long Sides of Chassis 15 Center Angle Center Surface 16 Holes for Inserting Input Connector (F-type Connector or F Plug) 17 Short Sides of Chassis Extrusion drawing part 18 Extrusion drawing part on the short side of the chassis 19 External drawing part 19a on the outer edge of the input connector hole 16 Outer drawing part shoulder 20 Punching part 21 Push-in claw part 22 Push-in draw part 23 Push-in claw The umbilicus-shaped protrusion 24 in the center of the part 21 The punching line 25 on the upper part of the pushing claw 21 The punching part 26 The punching part 27 The fitting protrusion 28 The fitting protrusion 29 The pushing claw 30 The pressing drawing part (30 Note) 31 punched part 32 punched part 33 punched part 34 push-in claw 35 push-in Drawing processing part 36 Umbilical protrusion part 37 in the center of pushing claw part 37 Stamping line 38 Projection part 39 Projection parts 40, 41, 42, 43 Partition plate 44 Bridge part 45 Hole for inserting feedthrough capacitor 46 Upper shield cover Projection 47 for Hanging and Fixing Projection 48 for Hooking and Fixing the Lower Shield Lid 48 Projection Part 49 for Hooking and Fixing the Upper Shield Lid 50 Projection 50 for Hooking and Fixing the Upper Shield Lid Connector (or F plug) 51 Upper shield lid 52 Notch portion 53 of shield lid 51 Lower shield lid 54 Notch portion 55 of lower shield lid 53 Leg for attaching structure of tuner 56 Terminal rod 57 of feedthrough capacitor Chip Electronic circuits such as capacitors, chip resistors, semiconductors, diodes, ICs, coils and feedthrough capacitors Circuit board 58 on which elements are mounted Bridge portion 60 on the long side of the chassis above the punched wire 37 Gap between the long side surface 14 of the chassis and the circuit board 57 Center pin 62 of the F type connector Dielectric surrounding the center pin 61 of the F type connector Body insulator 63 Crimping flange of F-type connector (shell of F-type connector) 64 Crimping mark 65 Crush mark cracking mark 66 Capacitor 67 Chip component 68 Coil component 70 CATV input signal is input terminal 71 High pass filter 72 to 74 Input signal Switching circuits 75 to 77 High frequency amplification input tuning circuit 78 to 80 High frequency amplifier 81 to 83 High frequency amplification output tuning circuit 85, 87, 89 Local oscillation circuit (parallel type local oscillation circuit) 84, 86, 88 Mixing circuit 90 IF amplification circuit 91 SAW filter circuit 92 IF filter circuit 93 Output terminal 4 AGC terminal 95 the data terminal 96 upstream circuit 97 power source terminal

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H03J 1/00 H04B 1/08 H05K 5/03

Claims (3)

(57) [Claims] And 1. A circuit board having electronic circuit elements such as transistors and resistors and feedthrough capacitors, a chassis angle, and the shield cover, the structure of a tuner having an input connector, contact to the chassis of the input connector the outside diameter of the face, about <br/> Kakarinia Ri greater than a thickness of the chassis angle, of the chassis angle of attaching the input connector
On the short side of the chassis, apply the protrusion of the short side of the chassis.
The work part and the outer drawing part on the outer periphery of the short side surface of the chassis.
Install the input connector into the protruding drawing part.
Is formed in an arc shape with respect to the hole
A tuner structure characterized in that the tuner structure is formed in a π type shape in which two angles are formed from an arc shape . 2. A transistor, a resistor, a feedthrough capacitor, etc.
Circuit board with electronic circuit elements and chassis angle
Of a tuner having a shield lid and an input connector
In the structure, the contact surface of the input connector to the chassis
Has a larger outer diameter than the thickness of the chassis angle.
There is a squeeze on the side of the chassis length of the chassis angle.
A processing part and a pressing claw part are provided, and the pressing drawing process is performed.
A mechanism for sandwiching the circuit board between the pressing portion and the pushing claw portion.
And a umbilicus-shaped protrusion at substantially the center of the pushing claw.
A tuner structure characterized by being provided with. 3. The structure of the tuner according to claim 1 or 2.
In the tuner for the cable modem that consists of the body,
A plurality of different high frequency amplification input circuits, a high frequency amplifier,
High frequency amplification output circuit, frequency conversion circuit and local oscillation circuit
, Intermediate frequency amplifier circuit, SAW filter and audio
The target amplifier circuit (IF amplifier circuit) and the PLL tuning circuit
A tuner for a cable modem, including: