JP4524964B2 - Wireless circuit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio circuit of a radio used for remote control of an automatic gas meter reading system or equipment.
[0002]
[Prior art]
Conventionally, a monopole antenna, a loop antenna, or a plate-shaped inverted F antenna (hereinafter referred to as an inverted F antenna) is often used for a small wireless device. Among them, an inverted F antenna is small, thin, and has a relatively high gain, so that it is a mobile phone. It is often used as a built-in antenna for cordless telephones.
[0003]
FIG. 9 shows a conventional portable wireless device mounting structure. 9A is a front view, FIG. 9B is a side view, 40 is an inverted F antenna (unit), 41 is a radiating conductor plate that is a radiating element of the inverted F antenna, and 42 is a radiating conductor plate. Short-circuit conductor plate for grounding, 43 is a strip line for feeding a high-frequency signal, 44 is a feeding conductor plate for an inverted-F antenna connected to the strip line, and 45 is a high-frequency circuit on which a high-frequency circuit for transmitting and receiving radio signals is mounted. A printed circuit board on which a control circuit of the radio is mounted; 47 a shield case for shielding a high-frequency circuit or a printed circuit; 48 a ground conductor plate provided opposite to the radiation conductor plate; and 49 a ground The dielectric is loaded between the conductor plate 48 and the radiating conductor plate 41.
[0004]
The inverted F antenna 40 has a radiating conductor plate 41 and a grounding conductor plate 48 facing each other, and a dielectric 49 is sandwiched between the conductor plates, and the grounding conductor plate is interposed at the end of the radiating conductor plate 41 via a short-circuiting conductor plate 42. 48, and the ground conductor plate 48 is connected to the high-frequency substrate 45 by soldering. The feeding strip line 43 extending from the high-frequency circuit board 45 is connected to the feeding conductor plate 44 connected to the radiation conductor plate 41 by soldering so as to feed power to the inverted F antenna.
[0005]
[Problems to be solved by the invention]
However, in the conventional configuration, when resin coating is to be performed on the high-frequency circuit and the printed circuit board, both the high-frequency circuit and the signal processing circuit are framed, and the resin coating is performed in a separate frame, respectively. The method of covering the shield case must be performed, and sufficient space must be secured for the frame of the resin coating, and the high-frequency circuit coating frame and the signal processing circuit between the high-frequency circuit and the signal processing circuit In order to install a shield case between the coating frame, it is necessary to have a resin-uncoated portion, and there is a problem that the resin coating cannot be performed on the wiring portion between the high-frequency circuit and the signal processing circuit.
[0006]
Also, if the high-frequency circuit is shielded alone and both the high-frequency circuit and the signal processing circuit are to be shielded, two shield cases are required: a high-frequency circuit shield case and a signal processing circuit shield case. There is also a problem that the cost becomes high considering the man-hours and material costs.
[0007]
In addition, when the shield case is divided into two parts, an outer frame part and a lid part, when the lid part is attached to the outer frame part by contact, strength cannot be obtained, and a connection method such as soldering the outer frame part and the lid part is required. .
[0008]
Further, in the above conventional example, when a shield case is placed on the high-frequency circuit unit and a short-circuit conductor is to be connected to the shield case, a separate conductor case is required, resulting in high cost.
[0009]
Further, when both the high-frequency circuit and the signal processing circuit are shielded and the short-circuit conductor of the inverted F antenna is to be connected, the high-frequency circuit shield case, the signal processing circuit shield case, and the two shield cases A short-circuit conductor has to be provided so as to cover it, and there has been a problem of high costs.
[0010]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and in a large-sized component such as a battery or an RF unit, the mounting space and the dimension in the thickness direction are restricted. The resin coating is applied and both the high-frequency circuit and the signal processing circuit can be shielded at low cost. Even when the shield case is divided into two parts, the outer frame part and the lid part, the outer frame part and the lid part are connected by contact. It is possible to shield both the high-frequency circuit and the signal processing circuit and connect the short-circuit conductor of the inverted F antenna to achieve this effect at a low cost.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a printed circuit board in which a shield consisting of a conductor is attached between a signal processing circuit and a high frequency circuit, and this shield is used as a part of the outer frame of the resin coating. Are connected between the signal processing circuit and the high-frequency circuit.
[0012]
Further, the shield case is formed by bending three sides of the plate-like conductor plate, and the other one side of the plate-like conductor plate that is not bent is adjusted to the width of the shield gap, thereby making this shield case a printed circuit. When connecting to a substrate, both the signal processing circuit and the high-frequency circuit can be shielded.
[0013]
The shield case is composed of two parts, an outer frame portion and a lid portion, and the outer frame portion has a surface facing the radiation conductor plate connected by a conductor such as a lattice.
[0014]
The printed circuit board has a shield gap made of a conductor between the signal processing circuit and the high-frequency circuit, and a plate-like conductor plate attached to the shield gap between the shield gap and the shield case.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a printed circuit board having a signal processing circuit and a high-frequency circuit wiring pattern on one side and a grounding conductor pattern on the other side, a radiation conductor plate facing the surface of the grounding conductor pattern, and the radiation A short-circuit conductor having one end connected to a conductor plate, a power supply conductor portion that supplies a high-frequency signal to the radiation conductor plate, and a shield case that shields a high-frequency circuit, and the printed circuit board includes the signal processing circuit and the high-frequency signal A shield circuit made of a conductor is attached between the circuit and the signal processing circuit of the printed circuit board and the high-frequency circuit are resin-coated using the shield cable as a part of the outer frame of the resin coating. Formed.
[0016]
As a result, when resin coating is to be applied to the high-frequency circuit and the printed circuit board, both the high-frequency circuit and the signal processing circuit are framed, and the ones that have been resin-coated in separate frames are combined into one outer frame. Since the resin coating is applied, the number of components can be reduced, the number of parts can be reduced, the number of assembly and adjustment processes can be reduced, and the uncoated part of the resin coating between the high-frequency circuit and the signal processing circuit can be eliminated. be able to.
[0017]
In the present invention, a shield gap is attached between the signal processing circuit and the high-frequency circuit, and when the shield case is connected to the printed circuit board, both the signal processing circuit and the high-frequency circuit are shielded. Thus, both the signal processing circuit and the high frequency circuit can be shielded.
[0018]
Further, the present invention improves the shielding effect of the high-frequency circuit by having the projection in the shield and the hole in the short-circuit conductor plate, and the short-circuit conductor plate is inserted and connected to the projection in the hole in the hole. be able to.
[0019]
Further, according to the present invention, the shield shim has a contact part having a spring property, and the connection between the short-circuit conductor plate and the shield shim is electrically contacted by the contact part having the spring property of the shield shim so that the shield property of the high frequency circuit is obtained. Can be improved without soldering.
[0020]
According to the present invention, the shield case includes an outer frame portion and a lid portion, and the outer frame portion is connected to a surface facing the radiation conductor plate, so that the outer frame of the shield and the outer surface of the resin coating are provided. The frame can also be used, and sufficient lid mounting strength can be provided by contact alone without soldering the outer frame portion and the lid portion.
[0021]
Further, the present invention attaches a shield made of a conductor between the signal processing circuit of the printed circuit board and the high frequency circuit, and further attaches a plate-like conductor plate between the shield and the shield case to the shield. Even when both the circuit and the signal processing circuit are shielded and the shorted conductor of the inverted F antenna is to be connected, this effect can be realized at low cost.
[0022]
【Example】
Example 1
Embodiment 1 of the present invention will be described below. FIG. 1 is a system configuration diagram of a wireless gas automatic meter reading system. The outline | summary about a radio | wireless automatic gas meter-reading system is demonstrated using FIG. 1, and the board | substrate mounted plate-shaped antenna currently used for the said system is demonstrated after that.
[0023]
In FIG. 1, 1 is a gas meter that integrates and measures the gas usage of a consumer, 2 is a wireless adapter slave connected to the gas meter and communicates wirelessly, and 3 is a wireless adapter parent that communicates wirelessly with the wireless adapter slave. 4 is a T-NCU (Terminal-Network Control Unit), to which a wireless adapter base unit is connected and has a line control function, 5 is a wall surface of the house where the T-NCU 4 and the wireless adapter base unit 3 are attached, and 6 is A public line network 7 connected to the T-NCU is a metering center of a gas supplier that is connected to the public line network 6 and reads the amount of gas used by consumers.
[0024]
Next, the operation will be described. The meter reading center 7 of the gas supplier transmits a gas metering request to the gas meter 1 at the customer's house via the public line network 6 to the T-NCU 4 at the customer's house. Is communicated to the wireless adapter base unit 3 and transmitted to the wireless adapter slave unit 2 by radio and transmitted to the gas meter 1. And the gas meter 1 is the structure which returns a meter-reading value to the meter-reading center 7, tracing back the same path | route reversely.
The wireless adapter slave unit 2 and the wireless adapter master unit 3 use a frequency band for specific low-power radio telemeter / telecontrol in the 429 MHz band.
[0025]
Next, a mounting board in a wireless adapter used in the wireless gas meter reading system will be described. FIG. 2 is an external configuration diagram of a mounting board having a board-mounted plate antenna built in the wireless adapter. FIG. 3 is an external configuration diagram when the wireless adapter slave unit 2 incorporating the plate antenna is attached to the gas meter 1.
[0026]
In FIG. 2, 8 is a radiating conductor plate forming a radiating element of a plate antenna, 10 is a printed circuit board on which a control circuit of the wireless adapter is mounted, and 11 is a printed circuit board having one end connected to the radiating conductor plate 8. 10 is a short-circuit conductor connected to the entire ground facing the radiation conductor plate, 12 is an entire ground pattern on the radiation conductor plate side of the printed circuit board 10 (entire ground conductor pattern), and 14 is an antenna input / output terminal of the high-frequency circuit. A power supply conductor portion that is connected via a wiring pattern and feeds a radio signal (high-frequency signal) to the radiation conductor plate 8, 15 is a shield case that shields the high-frequency circuit, and 16 is mounted on the surface of the printed circuit board 10 and is wireless. It is a lithium battery that is the power source of the adapter. Note that the entire ground pattern greatly affects the characteristics of the radiation conductor plate. For example, the larger the area of the entire ground pattern, the higher the possibility that the radiation gain characteristic of the radio wave radiated from the radiation conductor plate will be improved.
[0027]
Further, as shown in FIG. 3, the wireless device board mounted on the printed circuit board 10 is built in a resin casing to constitute the wireless adapter slave unit 2, and is attached to the front surface of the gas meter 1 for connection.
[0028]
Next, the configuration, operation, and action will be described. In the plate-like antenna in FIG. 2, the radiation conductor plate 8 is formed with a short-circuit conductor 11 and a feeding conductor portion 14 at one end at one end. On the other hand, the short-circuit conductor 11 and the feed conductor portion 14 are configured to be bent vertically.
[0029]
Furthermore, a plate-like antenna is formed by the radiation conductor plate 8 in which the short-circuit conductor 11 and the feeding conductor portion 14 are integrally molded and the radiation conductor plate 8 side single-sided ground 12 on the printed circuit board 10. Further, a lithium battery 16 that is a power source of the radio is mounted on the printed circuit board 10. Then, the wireless device formed on the printed circuit board 10 is built in a resin casing and attached to the gas meter 1 or the house wall surface 5 as the wireless adapter slave unit 2 or the wireless adapter master unit 3, respectively.
[0030]
The radiating conductor plate 8 has a configuration using copper, which is a high conductivity material, in order to improve the gain.
[0031]
The printed circuit board 10 is provided with a shield gap 17 made of a conductor between the signal processing circuit 19 and the high-frequency circuit 18, and the shield gap is formed as a part of the resin coating outer frame 20 with the signal processing circuit 19 of the printed circuit board. The high frequency circuit 18 is resin-coated, and a shield case 15 is connected so as to cover it from above.
[0032]
According to such a configuration, a plate-like inverted F antenna can be configured by the radiation conductor plate 8 and the one-sided full-surface ground 12 facing the radiation conductor plate 8 of the printed circuit board 10, and a high-frequency circuit and a printed circuit board. When resin coating is to be performed on a circuit board, both the high-frequency circuit and the signal processing circuit are framed, and the resin coating that has been applied in a separate frame is applied in a single outer frame. Therefore, for the above two reasons, it is possible to reduce the number of components, further reduce the number of parts, reduce the number of assembly steps and adjustment steps, and eliminate the uncoated portion of the resin coating between the high-frequency circuit and the signal processing circuit. Three things can be realized.
[0033]
In addition, although the present Example demonstrated using the radio | wireless adapter of the radio | wireless automatic meter-reading system of a gas meter, the radio | wireless machine used for radio | wireless systems, such as another installation apparatus, may be used.
[0034]
The configuration of the present embodiment can be applied to any of the following embodiments and has the same effect.
[0035]
(Example 2)
FIG. 4 is a configuration diagram in Embodiment 2 of the present invention.
[0036]
In FIG. 4, the same components as those in the above embodiment are given the same numbers, and the description thereof is omitted. In FIG. 4, reference numeral 21 denotes a shield case expanded to the signal processing circuit.
[0037]
According to such a configuration, even when both the high-frequency circuit and the signal processing circuit are shielded, both portions can be shielded by one shield case. The shield case may be formed by bending three sides of the plate-like conductor plate, and the remaining one side of the shield case not being bent may be adjusted to the width of the shield.
[0038]
(Example 3)
FIG. 5 is a configuration diagram in Embodiment 3 of the present invention.
[0039]
In FIG. 5, the same components as those in the above embodiment are given the same numbers, and the description thereof is omitted. In FIG. 5, reference numeral 22 denotes a shield hole having a protrusion, and reference numeral 23 denotes a shield case having a hole.
[0040]
Next, the configuration and operation will be described. The projecting portion of the shield hole 22 having the projection is inserted into the hole portion of the shield case 23 having the hole portion and soldered, thereby improving the shielding effect of the high-frequency circuit. Can do.
[0041]
Example 4
FIG. 6 is a configuration diagram in Embodiment 4 of the present invention.
[0042]
In FIG. 6, the same components as those in the above embodiment are given the same numbers, and the description thereof is omitted. In FIG. 6, reference numeral 24 denotes a shield gap having a projecting portion having a spring property.
[0043]
Next, the configuration and operation will be described. By bringing the projection of the shield drill 24 having a spring-like projection into contact with the inside of the shield case 21, the shield drill 24 and the shield case 21 are electrically connected. The shielding effect of the high frequency circuit can be improved without soldering.
[0044]
In addition, although demonstrated in the Example about the protrusion part, it is not restricted to this, What is necessary is just a contact part which contacts the shield hole 24 and a shield case.
[0045]
(Example 5)
FIG. 7 is a configuration diagram in Embodiment 5 of the present invention.
[0046]
In FIG. 7, the same components as those in the above embodiment are given the same numbers, and the description thereof is omitted. In FIG. 7, 25 is a shield case outer frame part, and 26 is a shield case cover part.
[0047]
Next, the structure and operation will be described. The shield case outer frame portion 25 is connected to the printed circuit board 10, and then the resin is coated with the shield case outer frame portion 25 as a resin coating outer frame. By covering from above, the shield case outer frame portion 25 and the shield case lid portion 26 can be held only by the contact strength. For this reason, there is no need to provide an outer frame of resin coating, and the four surfaces of the shield case outer frame portion 25 are connected by the upper lattice portion, so the shield case outer frame portion 25 and the shield case lid portion 26 are soldered. It is possible to hold only with the contact strength without doing so.
[0048]
(Example 6)
FIG. 8 is a configuration diagram in Embodiment 6 of the present invention.
[0049]
In FIG. 8, the same components as those in the above embodiment are given the same numbers, and the description thereof is omitted. In FIG. 8, reference numeral 27 denotes a plate-like conductor plate.
[0050]
Next, the configuration and operation will be described. Since the plate-like conductor plate 27 is attached to the shield gap between the shield gap 17 and the shield case 21, it is possible to reduce the cost without actually providing a double shield case. A double shield effect can be realized.
[0051]
The plate-like conductor plate 27 is basically attached in parallel with the substrate, but the attachment may not be in parallel with the substrate. Further, the size of the plate-like conductor plate 27 may be a shape that covers either the high-frequency circuit or the signal processing unit, or a shape that covers both the high-frequency circuit and the signal processing unit. Further, the size of the plate-like conductor plate 27 is not limited. ,
[0052]
【The invention's effect】
As described above, since the wireless circuit of the present invention has a shield gap between the high frequency circuit and the signal processing circuit, each of the high frequency circuit and the signal processing circuit is coated with a resin in a separate coating frame. It is possible to carry out resin coating with a single outer frame, and to eliminate the uncoated portion of the resin coating portion between the high frequency circuit and the signal processing circuit.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of a wireless gas automatic meter reading system. FIG. 2 is a configuration diagram of a wireless circuit in Embodiment 1 of the present invention. FIG. 3 is a gas meter mounting configuration of a wireless adapter with a plate antenna in Embodiment 1 of the present invention. FIG. 4 is a block diagram of a radio circuit in Embodiment 2 of the present invention. FIG. 5 is a block diagram of a radio circuit in Embodiment 3 of the present invention. FIG. 7 is a block diagram of a radio circuit in a fifth embodiment of the present invention. FIG. 8 is a block diagram of a radio circuit in a sixth embodiment of the present invention. Explanation】
DESCRIPTION OF SYMBOLS 8 Radiation conductor board 10 Printed circuit board 11 Short-circuit conductor 12 Whole surface ground pattern 14 Feeding conductor part 15 Shield case 16 Lithium battery 17 Shielding 18 High-frequency circuit 19 coated with resin 19 Signal processing circuit 20 coated with resin Resin-coated outer frame 21 Signal Shield case 22 expanded to the processing circuit Shield gap 23 with protrusions Shield case 24 with holes 24 Shield gap with spring-like protrusions 25 Shield case outer frame part 26 Shield case lid part 27 Plate-like conductor plate

Claims (3)

A printed circuit board having a signal processing circuit and a high-frequency circuit wiring pattern on one side, and a grounding conductor pattern on the other side;
A radiation conductor plate facing the surface of the ground conductor pattern;
A short-circuit conductor having one end connected to the radiation conductor plate;
A feeding conductor for supplying a high-frequency signal to the radiation conductor plate ;
Between the signal processing circuit and the high frequency circuit, a shield gap made of a conductor provided so as to cross a resin coating outer frame formed so as to surround the signal processing circuit and the high frequency circuit from the surroundings ; ,
A resin coating that covers the signal processing circuit and the high-frequency circuit by being formed at a location surrounded by the resin coating outer frame and the shield gap;
Comprising a shield case for shielding the upper and three sides of the high-frequency circuit,
A radio circuit characterized by surrounding the high-frequency circuit from the upper surface and surrounding four sides by arranging the shield case and shield shield in combination . The radio circuit according to claim 1, wherein the shield case has a shape located above the signal processing circuit together with the high-frequency circuit. It includes a protrusion on the shield sheet Kiri, comprising a hole in the shield case,
3. The radio circuit according to claim 2, wherein the shield case is connected by inserting a projection portion of the shield gap into the hole.

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