JPH0918211A - Parabolic antenna thawing device - Google Patents

Abstract

PURPOSE: To provide a parabolic antenna thawing device which can reduce its power consumption while keeping effectively the performance of an antenna reflector even at a low temperature. CONSTITUTION: This device includes a heater part 4 that is provided on the back side of a parabolic antenna 2, an open air sensor 6 and a snow sensor 8 which are prepared around the antenna 2, and a heater control part 10 which turns on the part 4 when the sensor 8 senses the snow. The part 10 has a 1st heater control function which turns off the part 4 when the sensor 6 detects the temperature lower than a prescribed level and a 2nd heater control function which turns on the part 4 when the open air rises up to a prescribed temperature from the temperature lower than a prescribed set level and then turns off the part 4 after the rapse of a prescribed time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snow melting device for a parabolic antenna, and more particularly to a snow melting device for a parabolic antenna intended to remove snow on a reflector of the parabolic antenna.

[0002]

2. Description of the Related Art A conventional snow melting device for a parabolic antenna is:
As shown in FIG. 5, a snow melting heater 51 for melting snow attached to the reflecting mirror 100, a snowfall detector 52 for detecting the presence or absence of snowfall, and a heater control unit 53 for controlling the operation of the snow melting heater 51 described above. And was composed of Among them, the snowfall detector 52 is set at a position where snowfall can be reliably detected without being shaded by a reflecting mirror or the like.

In this conventional example, when snowfall is detected by the snowfall detector 52, the snowmelt heater 51 is turned on (ON) to prevent snowfall on the reflecting mirror 100. Then, when the snowfall stops, the snow melting heater is controlled to be turned off (OFF) with a delay time of about a certain fixed time (for example, one hour).

Further, in Japanese Patent Laid-Open No. 62-77704, as shown in FIG. 6, the snow accretion detector 62 is attached to the reflecting mirror 100.
A method for detecting snow accretion on the reflector 100 by mounting the camera is disclosed. This method takes into account that adhesion to the reflecting mirror 100 is small particularly when the temperature is low, the wind is strong, or the amount of snowfall is small. A control method in which 51 is not turned on is adopted to prevent waste of energy.

Further, although it is not a snow melting device for an antenna, in JP-A-5-280225, based on an output signal of a snow detection device, when there is snow, the snow melting heater is turned on and the time after the snow stops Is disclosed, and a control method of turning off the snow melting heater after a lapse of a certain time is disclosed.

[0006]

Generally, in a snow melting device for a reflector antenna, a snowfall (dry dry snow) which is hard to accumulate at a low temperature and a certain temperature or less (for example, -10) is obtained. (° C. or lower), a control method of turning off the snow melting heater is adopted in order to suppress waste of energy.

In such a case, for example, snow starts to fall at an air temperature of -5 ° C., and after the snow melting heater operates, the air temperature drops to −
When the temperature falls below 10 ° C, the snow melting heater is turned off.
On the other hand, at this time, the temperature of the reflecting mirror is 0 ° C. or higher, and the snow falling continuously adheres to the reflecting mirror due to the residual heat.

Then, due to snow accretion on the antenna reflecting mirror, the antenna cannot maintain its original reflecting function, resulting in performance deterioration. Such a state has a drawback that it continues until the condition for turning on the snow melting heater is satisfied next time, that is, until the outside air temperature is −10 ° C. or more and snow falls next.

When the snowfall detector 52 of the antenna reflector 100 is used, only snowfall at that portion can be detected. In this case, when the snowfall is surely detected, the reflecting mirror 100 already has a certain amount of snowfall, and the performance of the antenna is deteriorated.

Further, in a certain amount of snow melting after snow accretion, the surface temperature of the reflecting mirror is maintained at 0 ° C. until the snow melts, so that the amount of heat taken from the reflecting mirror is reduced and the snow melting heater becomes high in temperature.
In the worst case, there is a drawback that the heating prevention circuit operates. what if,
Even if a control method in which the snow melting heater is turned on for a certain period of time after the snow has stopped is used, this problem cannot be avoided and the outside temperature is-
When the temperature is 10 ° C or lower, it is necessary to prepare a snow melting heater having a heat quantity enough to warm the antenna reflection surface to 0 degrees or more. If there is not such a heat quantity, even if the snow melting heater is turned on. , The snow on the antenna reflection surface cannot be melted. In addition, waste energy is consumed.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a snow melting apparatus for a parabolic antenna, which solves the disadvantages of the prior art and in which the power consumption is effectively reduced while effectively maintaining the performance of the antenna reflector at low temperatures. Its purpose is to provide.

[0012]

[Operation] When the outside air temperature becomes lower than a predetermined temperature (for example, -10 ° C), it becomes difficult for the snow to adhere during snowfall, so that the heater is turned off. After that, when the outside air temperature rises and returns to a predetermined temperature, the heater is turned on for a certain period of time with timer control regardless of the presence or absence of snowfall,
Melt the snow on the antenna reflection surface.

[0013]

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
It will be described based on. The first embodiment shown in FIGS. 1 to 3 includes a heater section 4 provided on the back side of the parabolic antenna 2, an outside air temperature sensor 6 for measuring the temperature around the parabolic antenna 2, A snowfall sensor 8 for detecting the presence or absence of surrounding snowfall, and a heater control unit 10 which is activated when the snowfall sensor 8 detects snowfall around the parabolic antenna and turns on the operation of the heater unit 4.
And Reference numeral 12 denotes a power supply unit for energizing and heating the above-described heater unit 4, and reference numeral 14 denotes an overheat detection sensor.

The heater control unit 10 operates when the outside air temperature sensor 6 detects a temperature lower than a predetermined set temperature (for example, -10 ° C .; the same applies hereinafter) to turn off the operation of the heater unit 4. A first heater control function, which is activated when the outside air temperature rises from a predetermined temperature or lower to a predetermined temperature, controls the operation of the heater unit 4 to be on, and after a predetermined time elapses, controls the operation of the heater unit 4. A second heater control function for performing off control.

Further, the heater control unit 10 has a third heater control function of controlling the heater unit 4 to be turned on for a fixed time after the input of the snowfall information is stopped when the snowfall information from the snowfall sensor 8 is stopped. It has.

Further, the above-described heater control unit 10 has a timer (second timer) 18 for inputting the outside air temperature information of the outside air temperature sensor 6. After elapse, the above-described second heater control function is executed.

This will be described in more detail. In the first embodiment, a whit air method is used in which warm air is blown from the heater to warm the antenna reflection surface.

The above-described heater section 4 is constituted by a blower heater, and is configured to blow warm air to the back side of the parabolic antenna 2. The entire rear surface of the antenna reflecting surface is surrounded by a heat insulating material called a chamber, and the heater unit (blower heater) 4 and the above-described overheat detection sensor 14 are provided inside thereof.

The outside air temperature sensor 6 is set to output a predetermined signal when detecting a predetermined outside air temperature (-10 ° C. in this embodiment).

The heater control unit 10 is the power supply unit 1 described above.
2 and the heater unit 4 are connected in series to the heater energizing circuit 12A and individually turned on / off (ON /
OFF) three switches to be driven, that is, first to third switches
Switches S ₁ , S ₂ , S ₃ .

The first switch S ₁ has a function to operate when the above-mentioned overheat detection sensor 14 outputs a predetermined overheat signal, and to turn off the above-mentioned energizing circuit 12A.
Accordingly, switch S ₁ of the first is normally set to the ON state. Reference numeral 15 denotes a switch driver for ON / OFF-driving the first switch S _1.

The second switch S ₂ has a function of outside air temperature sensor 6 turns off the energizing circuit 12A to the heater unit 4 operates when detecting a temperature below a predetermined set temperature (e.g., -10 ° C.) It has. Reference numeral 16 denotes an outside air temperature sensor 6
Input the predetermined information from to turn on the second switch S ₂ /
4 shows a switch driving unit that performs off driving. By this switch driving portion 16 and the second switch S _2, so that the first heater control function of the heater control unit 10 described above is executed.

The third switch S ₃ is connected to the first timer 17
To perform an on / off operation. When the snowfall information is input from the snowfall sensor 8, the first timer 17 immediately executes the third timer based on this information.
And a function of controlling turning on of the switch S _3.

Furthermore, when the snowfall information from the snowfall sensor 8 is stopped, the first timer 17 turns on the energizing circuit 12A for a fixed time (for example, one hour) after the input of the snowfall information is stopped. And a function of maintaining the heater unit 4 in an energized state (third heater control function).

The heater control unit 10 is connected in parallel to the series circuit portion of the _{second to} third switches S ₂ and S ₃ among the _{first to third} switches S _{1 to} S ₃ described above. A fourth switch S ₄ is provided.

The fourth switch S ₄ can be turned on / off by being energized by a second timer 18. The second timer 18 is operated by being urged by the outside air temperature sensor 6 described above. Specifically, it operates when the outside air temperature rises from a predetermined set temperature (for example, −10 ° C.) or lower to a predetermined temperature, turns on the above-described energizing circuit 12A, turns on the operation of the heater unit 4, and It functions to turn off the operation of the heater unit 4 after a lapse of a predetermined time. That is, the fourth switch S ₄ and the second timer 1
8, the second heater control function of the heater control unit 10 described above is executed.

Next, the operation of the first embodiment will be described with reference to FIGS. First, when snow begins to fall, the third switch S ₃ is turned on in response to a signal from the snowfall sensor 8, whereby the energizing circuit 12 of the heater unit 4 is turned on.
A is conducted, and the heater unit 4 is turned on. In this embodiment, this state is continuously maintained when the outside air temperature is, for example, -10 ° C. or higher, so that the attached snow is effectively melted.

Next, in snow, when the outside air temperature falls below a predetermined temperature (e.g., -10 ° C.), an outside air temperature sensor 6 senses this and outputs a predetermined signal, the second switch S ₂ off The heater is turned on, and the heater unit 4 is turned off (execution of the first heater control function by the heater control unit 10). If the outside air temperature is lower than −10 ° C., the snow becomes soft and dry, so that it is difficult for the snow to adhere even if the heater unit 4 is turned off.

Next, when the outside air temperature is equal to or greater than rising to -10 ° C. from -10 ° C. or less, the second timer 18 is started, the heater unit 4 on the fourth switch S ₄ at the same time Is turned on, and the heater unit 4 is operated. (And, as if rain snow) when the second timer 18 has passed a predetermined time (e.g., 1 hour), a fourth switch S ₄ is turned off to turn off the heater unit 4 (control heater Execution of the second heater control function by the unit 10).
Thus, the snow on the antenna reflection surface is completely melted, and the antenna performance is restored.

On the other hand, when the outside air temperature is higher than -10.degree.
When snowfall information from snow sensor 8 snow ceased is not output, the first timer 17 while maintaining the state of the switch S ₃ on is activated, a certain time (1 hour in this embodiment) switch S ₃ on state Will be maintained. Then, after the lapse of one hour, the switch S ₃ is turned off by the first timer 17 to release the energized heating state of the heater portion 4 (execution of the third heater control function). Even in this case, when the outside air temperature becomes -10 ° C or lower, the switch S is immediately pressed.
₃ is turned off, and the energized heating state of the heater unit 4 is released.

[0031]

Second Embodiment Next, the second embodiment will be described with reference to FIG. Here, the same reference numerals are used for the same components as those in the first embodiment.

In the second embodiment shown in FIG. 4, a rain sensor 21 and a second outside temperature sensor 22 are provided in place of the snow sensor 8 (see FIG. 4) in the first embodiment described above. It is characterized in that the outputs of the sensors 21 and 22 are input to the first timer 17 via the AND gate 23 and are used as drive signals for the timer 17.

The second outside air temperature sensor 22 can output a predetermined signal when the outside air temperature is below a predetermined temperature (for example, +4 degrees). Reference numeral 20 denotes a heater control unit. The AND gate 23 is provided in the heater control unit 20. Other configurations are the same as those of the embodiment shown in FIG. 1 described above.

In the embodiment shown in FIG. 4, the rain sensor 21 is activated when there is snow or rain. At this time, the outside air temperature sensor 22 also operates at the same time, and outputs a predetermined signal when the outside air temperature falls below a predetermined temperature (for example, +4 degrees). These two sensors 2
When a signal is output from the first and second signals, the AND gate 23 is activated, the heater control unit 20 determines that there is snowfall (this is also the case statistically), and the heater unit 4 is turned on (third switch S _3). To ON). Subsequent operation control is the same as in the first embodiment.

In the configuration of the heater control units 10 and 20, similar effects can be obtained regardless of whether the circuit is a relay logic circuit or a circuit using a microprocessor.

[0036]

As described above, according to the present invention, it is possible to prevent unnecessary energy consumption by melting the property of snow that is difficult to adhere to the reflecting surface of the attenuator at low temperature to turn off the heater. At the same time, when the heater is turned off, the change in the outside air temperature is monitored for the snow adhering to the antenna. For example, the temperature rises from below -10 ° C to -10 ° C. When it arrives, the heating heater is operated to melt the snow regardless of the presence or absence of snowfall, so that it is possible to provide an excellent snow melting device for a parabolic antenna, which is not available in the past, which can accelerate the recovery of the antenna function more quickly. You can

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of FIG.

FIG. 3 is an explanatory diagram showing operation timings of the heater in FIG. 1;

FIG. 4 is a block diagram showing a first embodiment.

FIG. 5 is a block diagram showing a conventional example.

FIG. 6 is a block diagram showing another conventional example.

[Explanation of symbols]

2 Parabolic antenna 4 Heater unit 6 Outside temperature sensor 8 Snowfall sensor 10, 20 Heater control unit 14 Overheat prevention sensor 17 First timer 18 Second timer 21 Rain sensor 22 Second outside temperature sensor 23 AND gate S ₁ First switch S2 _Second switch S3 _Third switch

Claims (3)

[Claims] 1. A heating heater unit provided on the back side of the parabolic antenna, an outside air temperature sensor for measuring the temperature around the parabolic antenna, and a snowfall sensor for detecting the presence or absence of snow around the parabola antenna, And a heater control unit that is activated when the snowfall sensor detects snowfall around the parabolic antenna, and controls the operation of the heating heater unit to be turned on. A first heater control function that operates when the following temperature is detected and controls the operation of the heating heater unit to be off, and operates when the outside air temperature rises from a temperature equal to or lower than a predetermined set temperature to a predetermined temperature. And a second heater control function for turning on the operation of the heater unit and turning off the operation of the heating heater unit after a lapse of a certain time. Bora antenna for snow melting apparatus. 2. The third heater control for turning on the heating heater unit for a certain period of time after the input of the snowfall information is stopped when predetermined snowfall information is stopped from the snowfall sensor. The snow melting device for a parabolic antenna according to claim 1, which has a function. 3. The heater control unit has a timer for inputting outside air temperature information of the outside air temperature sensor, and executes the second heater control function after a predetermined time set in the timer has elapsed. The snow melting device for a parabolic antenna according to claim 1 or 2.