JP2603100Y2 - Transmitter for weak radio waves - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter for a weak radio wave for use in, for example, a remote controller.

[0002]

2. Description of the Related Art Conventionally, such a transmitter for weak radio waves has
For example, it is configured as shown in FIG. That is, in FIG. 4, the transmitter 1 for weak radio waves includes a printed circuit board 2 on which a transmitting circuit is mounted on the surface, an upper shield case 3 disposed to cover the surface of the printed circuit board 2 from above,
And a lower shield case 4 disposed to cover the back surface of the printed board 2 from below. An antenna terminal 2a extending from one end of the printed board 2
An external antenna (not shown) such as a rod antenna is connected to the antenna terminal 2a by protruding outside from the cutout hole 3a provided in the shield case 3.

According to the transmitter 1 for a weak radio wave having such a configuration, the transmission circuit on the printed circuit board 2 shielded in the shield cases 3 and 4 appropriately processes the input signal to generate the transmission signal. After conversion, via the antenna terminal 2a,
It is transmitted as FM radio waves from an external antenna.

[0004]

However, in the transmitter for weak radio waves 1 configured as described above, the printed circuit board 2 is covered by the two shield cases 3 and 4 from above and below. Since the number of parts increases and the assembly becomes complicated, the cost of parts and assembly increases, and the overall thickness is relatively large because it cannot be made very thin and requires an external antenna. There was a problem that would be.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a transmitter for a weak radio wave which can be made compact with a simple structure, and which can be easily assembled and reduced in cost. And

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided, according to the present invention, a circuit part and a conductive pattern constituting a transmitting circuit, and a wiring for connecting these parts to each other. A horizontal pattern antenna and a vertical pattern antenna, each formed by a conductive pattern and connected to the transmission circuit, are provided on a part of the antenna and a surface of the antenna substrate provided perpendicular to the printed circuit board. Is provided with a solid ground made of a conductive pattern over substantially the entire surface corresponding to the transmission circuit.The transmission circuit on the front surface of the printed circuit board is covered with a shield case from above, and A weak radio wave transmitter, wherein the shield case is electrically connected to the solid earth. , It is achieved.

[0007]

According to the above construction, the transmission circuit and the horizontal pattern antenna for transmitting the FM radio wave and the like from the transmission circuit are provided on the printed circuit board, and the antenna is perpendicular to the printed circuit board. A vertical pattern antenna is provided on the substrate, and the solid ground on the back surface of the printed circuit board is electrically connected to a shield case that covers a portion of the transmission circuit on the surface of the printed circuit board, thereby forming the shield. The transmission circuit will be shielded together with the case.

[0008] Accordingly, the number of components is small and the components can be easily assembled, so that the cost of parts and the cost of assembly can be reduced.

Further, since the transmitting antenna is integrally provided as a horizontal pattern antenna and a vertical pattern antenna provided on the printed board and the antenna board, respectively, the whole is made thinner and smaller. At the same time, the polarization component of the transmission radio wave has horizontal and vertical components, the directivity is improved, and the level fluctuation of the transmission radio wave due to the direction of the main body of the transmitter for weak radio waves is small. Therefore, stable transmission can be performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of a transmitter for weak radio waves according to the present invention.

The weak radio wave transmitter 10 includes a printed circuit board 1.
1, that is, a circuit area A, which is provided with circuit components and conductive patterns to form a transmission circuit and wiring for connecting these components to each other,
Is configured.

Further, the transmitter 10 for weak radio waves is provided in another part adjacent to the circuit area A, that is, in the antenna area B.
The transmission circuit 12 formed of a conductive pattern
Is provided, and an antenna substrate 14 that rises in the vertical direction is attached near the boundary between the circuit region A and the antenna region B. On the antenna substrate 14, As shown in FIG.
Is provided with a vertical pattern antenna 15 connected to the antenna.

On the back surface of the printed circuit board 11, a solid ground (not shown) made of a conductive pattern is provided over the entire portion corresponding to the circuit region A.

Further, the printed circuit board 11 has a transmission circuit 12 disposed in a circuit area A on the surface thereof covered by a shield case 16 from above. Here, the shield case 16 is electrically connected to the solid ground by soldering at a plurality of locations.

The transmission circuit 12 is configured as shown in FIG. That is, in FIG.
2 indicates that the signal to be transmitted is transmitted from the input terminal 12a to the modulator 1
2b, oscillator 12c, filter 12d, and amplifier 12e
, Can be transmitted from the horizontal pattern antenna 13 and the vertical pattern antenna 15 as, for example, FM radio waves. Here, the power supplied to the power terminal 12h is controlled by the switch circuit 12g based on the strobe signal input from the input terminal 12f, and can be supplied to the modulator 12b, the oscillator 12c, and the amplifier 12e. I have.

The transmitter 10 for weak radio waves according to the present invention is configured as described above, and the transmission circuit 12 disposed in the circuit area A of the printed circuit board 11 includes the shield case 16.
And the shielding effect provided by the solid ground made of the conductive pattern.

Thus, the transmission circuit 12 on the printed circuit board 11 modulates the input signal by the modulator 12b, mixes the modulated signal with the carrier generated by the oscillator 12c, and amplifies the signal by the amplifier 12e via the band-pass filter 12d. Then, the signal is converted into a transmission signal, and is transmitted from the horizontal pattern antenna 13 and the vertical pattern antenna 15 as, for example, an FM radio wave.

At this time, since the transmission radio wave is transmitted from both the horizontal pattern antenna 13 and the vertical pattern antenna 15, it includes a horizontal polarization component and a vertical polarization component.

Accordingly, the directivity when the weak radio wave transmitter 10 is rotated about the axis in the direction of the arrow X, as shown by the solid line in FIG. It will be good. For reference, the horizontal pattern antenna 13
When only the vertical pattern antenna 15 is not provided, the directivity is indicated by a dotted line in FIG.

It should be noted that the antenna substrate 14 has a height substantially equal to the height of the shield case 16 so that
The antenna substrate 14 does not protrude upward, so that the whole can be made compact.

[0021]

As described above, according to the present invention, there is provided a transmitter for a weak radio wave, which can be reduced in size by a simple structure, can be easily assembled, and can be reduced in cost. Can be done.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a transmitter for weak radio waves according to the present invention.

FIG. 2 is a block diagram of a transmission circuit of the transmitter for weak radio waves in FIG. 1;

FIG. 3 is a graph showing directivity of the transmitter for weak radio waves of FIG. 1;

FIG. 4 is an exploded perspective view showing an example of a conventional transmitter for weak radio waves.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Weak radio wave transmitter 11 Printed circuit board 12 Transmission circuit 13 Horizontal pattern antenna 14 Antenna board 15 Vertical pattern antenna 16 Shield case

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B 1/03-1/034

Claims (1)

(57) [Scope of request for utility model registration] 1. A printed circuit board, comprising a circuit part and a conductive pattern constituting a transmission circuit on a part of the surface of the printed circuit board, and a wiring for connecting the circuit parts and the conductive pattern, and provided vertically to the other part and the printed circuit board. A horizontal pattern antenna and a vertical pattern antenna each formed of a conductive pattern and connected to the transmission circuit are provided on the front surface of the antenna substrate, and substantially the entire surface corresponding to the transmission circuit is provided on the back surface of the printed circuit board. And a transmitting circuit on the surface of the printed circuit board is covered from above with a shield case, and the shield case is electrically connected to the solid ground. A transmitter for weak radio waves.