JP2001284940A - Satellite broadcast receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a satellite broadcast receiver capable of controlling the elevation angle of an antenna in simple mechanism. SOLUTION: When the power source of the receiver is turned on, a driving motor starts rotating forward, a slide pin moves downward, the offset control of an input voltage is performed for stabilizing a detection circuit during that movement, and the elevation angle of the antenna is enlarged. At such a time, a voltage is stored in the detection circuit. Further, when the driving motor is rotated backward, the slide pin moves upward and the elevation angle is reduced. In this case, the voltage is compared with the stored voltage in comparator circuit and the higher voltage is selected. The driving motor is rotated to provide the selected elevation angle and elevation angle control is completed. Further, the driving motor is continuously rotated, the present voltage is compared with the stored maximum voltage. When the voltage is equal with the maximum voltage or reaches an allowable range, the driving motor is stopped and azimuth angle control is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcast receiving apparatus mounted on an automobile or the like to receive satellite broadcasts. In particular, the present invention relates to a satellite broadcast receiving apparatus capable of adjusting the elevation angle with a simple mechanism.

[0002]

2. Description of the Related Art Hitherto, many proposals have been made for satellite broadcast receiving apparatuses for receiving satellite broadcasts on a moving body such as an automobile or a ship.

[0003]

Problems to be Solved by the Invention For example, Japanese Patent Publication No. 5-8
No. 4681 discloses a satellite broadcast receiving apparatus capable of adjusting the azimuth and elevation of an antenna. This device is provided with two axes for adjusting the azimuth and elevation and two motors for driving each axis. In this example, the azimuth and the elevation can be freely adjusted, so that a favorable reception state can be obtained. However, since two driving motors and the like are required to drive them, the device becomes expensive.

Japanese Patent Application Laid-Open No. Hei 8-162833 discloses a satellite broadcast receiving apparatus in which an antenna is arranged at a portion where a cylindrical body is obliquely cut. The elevation angle of the antenna cannot be adjusted, only the azimuth angle can be adjusted by the drive motor. In this example, it is inexpensive because only one drive motor is required. However, since the elevation angle of the antenna cannot be adjusted, the reception state is poor and ghosts and the like occur.

The present invention has been made in view of such a problem, and has as its object to provide a satellite broadcast receiving apparatus capable of adjusting the elevation angle of an antenna with a simple mechanism.

[0006]

According to a first aspect of the present invention, there is provided a satellite broadcast receiving apparatus comprising: an antenna; an azimuth adjusting mechanism for changing an azimuth of the antenna; and an elevation angle of the antenna. And a detecting means for detecting radio waves received by the antenna to determine a high-sensitivity antenna position. A satellite broadcast receiving apparatus comprising: an elevation angle adjusting mechanism using an actuator of the azimuth adjusting mechanism; The adjustment mechanism is adjusted in multiple stages. In this embodiment, an actuator for adjusting the elevation angle is not required. Therefore, the receiving sensitivity is improved with a simple configuration.

[0007] A satellite broadcast receiving apparatus according to a second aspect of the present invention comprises:
The elevation angle adjusting mechanism adjusts the elevation angle of the antenna in two stages, high and low. In Honshu, Japan, for example,
In the case of receiving radio waves from BS-3a / b (satellite names), the elevation angles of broadcast satellites are 33.3 ° in Aomori and 43.4 ° in Hiroshima. However, if the elevation angle can be switched in two stages, for example, 37 ° below (near Mito) and 40 ° above (near Nagoya), there is no practical problem. Nevertheless, the receiving sensitivity can be improved more significantly than that of the fixed elevation type, for example, that disclosed in JP-A-8-162833.

[0008] A satellite broadcast receiving apparatus according to a third aspect of the present invention comprises:
The rotation force of the actuator of the azimuth adjustment mechanism is transmitted to the elevation adjustment mechanism via a cam.
In this embodiment, since the elevation angle can be adjusted via the cam, the mechanism can be relatively simplified. Further, the elevation angle can be adjusted to various angles by slightly changing the design of the cam.

A satellite broadcast receiving apparatus according to a fourth aspect of the present invention comprises:
The antenna elevation angle is adjusted in two stages, high and low, according to the rotation direction of the actuator of the azimuth adjustment mechanism. In this aspect, the elevation angle can be adjusted only by changing the rotation direction of the actuator of the azimuth angle adjustment mechanism, so that the adjustment operation can be simplified.

In the above-mentioned satellite broadcast receiving apparatus, a rotational position of an actuator of the azimuth adjusting mechanism is detected,
It is preferable to have a detection circuit that performs a detection operation. With the detection circuit, the azimuth and elevation of the antenna are automatically adjusted just by turning on the power of the satellite broadcast receiving apparatus.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a satellite broadcast receiving apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 2 is a side view showing the entire configuration of the satellite broadcast receiving apparatus according to one embodiment of the present invention. At the bottom of the figure,
A roof 3 of an automobile or the like is illustrated. On the roof 3, a base 35 of the satellite broadcast receiving device 1 is mounted. A drive motor 33 is installed on the base 35 with an output shaft (not shown) facing downward. A speed reducer 34 is connected below the drive motor 33 to reduce the motor speed. The output shaft 34 a of the speed reducer 34 projects below the base 35. A pinion gear 37 is fitted into the output shaft 34a. Drive motor 33, reducer 3
4, a cylindrical cam 17 is disposed on the right side. The cam 17 is rotatably attached to the base 35 via a bearing 39. A cam gear 31 is fixed to a lower portion of the cam 17, and the cam gear 31 meshes with a pinion gear 37.

A cam groove 17a penetrating the cam side wall is formed on the right side of the cam 17 in the drawing. The shape of the cam groove 17a will be described later with reference to FIG. An intermediate ring 20 is fitted inside the cam 17 so as to be vertically movable and rotatable. A slide pin 21 is fixed to the intermediate ring 20. The slide pin 21 is fitted in the cam groove 17a. Further, a piston 19 is provided so as to sandwich the intermediate ring 20 from above and below. Piston 19
, Only the vertical movement of the intermediate ring 20 is transmitted. A spring 23 is provided on the right side of the slide pin 21 in the drawing.
It is installed to hang on. This spring 23 has a base 3
5 is fixed. Although a leaf spring is used as the spring 23 in this embodiment, the present invention is not limited to this.

A boomerang-like bracket 15 is arranged above the piston 19. A rotation fulcrum 15a is provided on the left side of the bracket 15 in the drawing, and an action point 1 is provided on the right side of the drawing.
5b. The fulcrum 15a of the bracket 15 is
3 is rotatably attached to a pin hole 17b (see FIG. 3) by a pin 16a. Action point 1 of bracket 15
5b is provided with a pin 16 (not shown)
b so as to be rotatable. Thus, the rotation of the cam 17 is transmitted to the piston 19 via the bracket 15.

The bracket 15 has a bearing 13
The antenna frame 7 is installed rotatably. The antenna 5 is fixed to the upper left of the drawing of the frame 7. Note that a converter 9 is provided inside the frame 7.
Wiring 11 is connected to converter 9, and is guided to outside of satellite broadcast receiver 1 through frame 7, piston 19, and the like.

Next, the shape of the cam 17 will be described in detail. FIG. 3 is a diagram showing the shape of the cam of the device according to the present embodiment. 3 (A) is a plan view of the cam as viewed from above in FIG. 2, and FIG. 3 (B) is a side cross-sectional view as viewed from the AA ′ section of FIG. 3 (A). FIG. 3C is a development view of the cam groove 17a viewed from the direction indicated by the symbol P in FIG. FIG. 3 shows the cam 17. In this embodiment, the outer diameter of the cam 17 is 56 mm and the height is 38 mm.
The cam 17 has a cam groove 17a formed to penetrate the side wall. As shown in detail in FIG.
a has a structure in which the heights of the left and right end portions are different. The upper end is denoted by U and the lower end by D. The width of the cam groove 17a is 8 mm, and the difference in height between the end U and the end D is 3 mm. When the slide pin 21 fitted in the cam groove 17a slides to the ends U and D, both ends of the cam groove 17a are horizontal so as to be stabilized there.

The left side of the cam 17 shown in FIG.
It is one step higher and has a pin hole 17b.
The height of the raised portion of the cam 17 is 49 mm, and the diameter of the pin hole 17b is 5 mm. A pin 16a for rotatably engaging the fulcrum 15a of the bracket 15 is fitted into the pin hole 17b.

Next, the configuration of the detection circuit according to the embodiment of the present invention will be described. FIG. 4 is a diagram schematically illustrating a detection circuit and the like of the device according to the present embodiment. The antenna 5 is illustrated at the top of the figure. A converter 9 is attached to the antenna 5 as shown in FIG. Wiring 11 is connected to converter 9. A branch 41 is attached to the end of the wiring 11. A detection circuit 51 is connected to the end of the branching device 41. Detection circuit 51
Comprises a peak hold circuit 55, a comparison circuit 57, a control circuit 59, and the like. A reset switch 61 is attached to the peak hold circuit 55. The drive motor 33 of the antenna 5 is connected to the end of the control circuit 59. The operation of this circuit will be described later.

A method of adjusting the elevation and azimuth of the antenna of the above-mentioned satellite broadcast receiving apparatus will be described. FIG. 1 is a flowchart showing a method of adjusting the antenna elevation and azimuth of the satellite broadcast receiving apparatus according to the embodiment of the present invention.

First, a method of adjusting the elevation angle of the antenna will be described. A vehicle equipped with the satellite broadcast receiving device 1 (see FIG. 2) moves to a camp site or the like and stops. Therefore, the satellite broadcast receiver 1 is turned on to receive the satellite broadcast.
When the power is turned on, the drive motor 33 in the satellite broadcast receiver 1 is turned on.
Rotates forward (clockwise as viewed from above the satellite broadcast receiver). When the drive motor 33 rotates forward, the cam 17 rotates reversely (counterclockwise as viewed from above the satellite broadcast receiver) via the gears 31 and 37. Thus, the slide pin 21 fitted in the cam groove 17a reaches the end D shown in FIG. Since the height of the end D is relatively low in the cam groove 17a, the slide pin 21, the intermediate ring 20, and the entire piston 19 move downward. When the piston 19 moves downward, the bracket 15 rotates clockwise about the fulcrum 15a. Then, the elevation angle of the antenna 5 fixed to the end of the bracket 15 increases. In this embodiment, the elevation angle reaches 42.9 ° (near Okayama) at this position. During this series of movements, offset adjustment of the input voltage is performed to obtain the stability of the detection circuit. Note that the rotation of the cam 17 and the like causes the wiring 11 to be twisted. However, the torsion is released by the rotation of the antenna 5 and the like via the bearing 13.

When the elevation angle reaches this position, the antenna 5 is further rotated once, and at that time, a part of the received signal from the converter 9 is extracted by the splitter 41 (see FIG. 4). The signal is detected and amplified by the detection and amplification circuit 53. The detection amplification circuit 53 outputs a voltage proportional to the magnitude of the received signal. This voltage is input to the peak hold circuit 55 and stored therein.

Next, the driving motor 33 is reversed. Accordingly, the reverse operation occurs. The cam 17 rotates forward and moves to the higher end U of the cam groove 17a so that the slide pin 21 is pressed by the spring 23. As a result, the intermediate ring 20 and the piston 19 move upward,
The elevation angle of the antenna 5 becomes smaller. In this embodiment, the angle of elevation reaches 37.7 ° (near Mito) at this position.

Similarly to the above, when the elevation angle reaches this position, the antenna 5 is further rotated once, and at that time, a part of the received signal from the converter 9 is extracted by the splitter 41 (see FIG. 4). The signal is detected and amplified by the detection and amplification circuit 53. The detection amplification circuit 53 outputs a voltage proportional to the magnitude of the received signal. This voltage is input to the comparison circuit 57 differently from the above. Therefore, the voltage is compared with the voltage value stored in the peak hold circuit 55 at the elevation angle. The larger one of the two voltage values (the greater the strength of the received radio wave), that is, the better received radio wave state is selected, and the control circuit 5 reproduces the elevation angle at that time.
Send a signal to 9. The control circuit 59 issues a command to the drive motor 33 according to this signal. Thereby, the drive motor 33
Rotates, and the slide pin 21 moves to a desired position. In this way, the elevation angle of the antenna 5 is adjusted to a better reception state among the two. The maximum value of the voltage values when the azimuth is changed by rotating the antenna 5 is stored in the peak hold circuit 55 as the maximum voltage.

Next, a method of adjusting the antenna azimuth will be described. For example, when the former large elevation angle is selected by the above-described method, the drive motor 33 automatically rotates forward again by the command of the detection circuit 51. In response, the cam 17 rotates in the reverse direction, and moves to the end D of the cam groove 17a so that the slide pin 21 is pressed by the spring 23. At this time, as described above, the slide pin 21 and the piston 19 move downward, and the elevation angle of the antenna 5 increases.

When the drive motor 33 continues to rotate forward,
The cam 17 also continues to reverse. At this time, the slide pin 21 has reached the end D of the cam groove 17a,
, The slide pin 21 does not move, and the slide pin 21 repels the spring 23 (so that the slide pin 21 flips the spring 23), and the cam 17 continues to rotate. Therefore, the intermediate ring 20 to which the slide pin 21 is attached, the piston 19 and the cam 17 rotate integrally. Thus, the drive motor 33 continues to rotate forward while the slide pin 21 flips the spring 23, and the azimuth can be adjusted.

While the drive motor 33 rotates as described above, a part of the received signal from the converter 9 is continuously extracted by the branching device 41 (see FIG. 4) as shown in FIG. The signal is detected and amplified by the detection and amplification circuit 53. The detection amplification circuit 53 outputs a voltage proportional to the magnitude of the received signal.

The current voltage value is input to the comparison circuit 57. Then, it is compared with the stored maximum voltage value.
When the current voltage value is equal to the stored maximum voltage or has reached an allowable range, a signal is sent to the control circuit 59 to stop the drive motor 33. At this time, the peak hold circuit 55 is used for the next elevation and azimuth adjustment.
Are reset by the reset switch 61. The control circuit 59 issues a stop command to the drive motor 33 according to this signal. As a result, the drive motor 33 stops, and the antenna 5 faces the desired direction. In this way, the direction of the antenna 5 is also adjusted to a direction in which the reception state is better.

The satellite broadcast receiving apparatus according to the first embodiment of the present invention has been described with reference to FIGS. 1 to 4, but the present invention is not limited to this. You can make various changes to. Instead of sliding the slide pin in the cam groove, the slide pin may be moved up and down. In this case, the pin that moves up and down can be directly controlled by the drive motor to adjust the elevation angle.
Furthermore, a plurality of the vertically moving pins are used, each of which is controlled by a drive motor, so that the azimuth as well as the elevation can be simultaneously adjusted in multiple stages.

[0028]

As is apparent from the above description, according to the present invention, the elevation angle of the antenna of the satellite broadcast receiver can be easily adjusted with a simple structure.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a method of adjusting an antenna elevation angle and an azimuth angle of a satellite broadcast receiving apparatus according to an embodiment of the present invention.

FIG. 2 is a side view showing the overall configuration of the satellite broadcast receiving apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram showing a shape of a cam according to the embodiment of the present invention. 3 (A) is a plan view of the cam as viewed from above in FIG. 2, and FIG. 3 (B) is a side cross-sectional view as viewed from the AA ′ section of FIG. 3 (A). FIG. 3C is a development view of the cam groove 17a viewed from the direction indicated by the reference numeral P in FIG. 3A.

FIG. 4 is a diagram schematically showing a detection circuit and the like according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Satellite broadcast receiving device 3 Roof 5 Antenna 7 Frame 9 Converter 11 Wiring 13 Bearing 15 Bracket 17 Cam 19 Piston 20 Intermediate ring 21 Slide pin 23 Spring 31 Cam gear 33 Drive motor 34 Reduction gear 35 Base 37 Pinion gear 39 Bearing 41 Branching device 51 Detection circuit 53 Detection amplification circuit 55 Peak hold circuit 57 Comparison circuit 59 Control circuit 61 Reset switch

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 5C025 AA21 DA04 DA07 5C064 DA08 5J021 AA01 DA02 DA07 EA01 FA21 FA30 GA02 HA07 HA10 JA07 5J047 AA04 AA07 AA19 AB03 BF04 BF10 BF11

Claims (4)

[Claims] An antenna, an azimuth adjusting mechanism for changing an azimuth of the antenna, an elevation adjusting mechanism for changing an elevation of the antenna, and a detecting means for detecting a radio wave received by the antenna to determine a high-sensitivity antenna position A satellite broadcast receiving apparatus comprising: an elevation angle adjustment mechanism that is adjusted in multiple stages using an actuator of the azimuth angle adjustment mechanism. 2. An antenna, an azimuth adjusting mechanism for changing an azimuth of the antenna, an elevation adjusting mechanism for changing an elevation of the antenna, and a detecting means for detecting a radio wave received by the antenna to determine a high-sensitivity antenna position. A satellite broadcast receiving apparatus comprising: an elevation angle adjustment mechanism that adjusts an elevation angle of an antenna in two stages, high and low. 3. An antenna, an azimuth adjusting mechanism for changing an azimuth of the antenna, an elevation adjusting mechanism for changing an elevation of the antenna, and a detecting means for detecting a radio wave received by the antenna to determine a high-sensitivity antenna position. A satellite broadcast receiving apparatus comprising: transmitting a rotational force of an actuator of the azimuth angle adjusting mechanism to the elevation angle adjusting mechanism via a cam. 4. An antenna, an azimuth adjustment mechanism for changing an azimuth of the antenna, an elevation adjustment mechanism for changing an elevation of the antenna, and a detecting means for detecting a radio wave received by the antenna to determine a high-sensitivity antenna position. A satellite broadcast receiving apparatus comprising: a satellite broadcast receiving apparatus, wherein the antenna elevation angle is adjusted in two stages, high and low, according to a rotation direction of an actuator of the azimuth angle adjusting mechanism.