JPS5937915Y2 - Agricultural remote temperature display device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an agricultural remote temperature display device that displays the temperature of an agricultural facility such as a greenhouse or a poultry house at a central location in a farmhouse or the like that is remote from the facility.

Conventionally, devices have been developed that send alarm signals to farmers wirelessly when the temperature of agricultural facilities drops below a certain value, but devices that display temperature are expensive, so they are still being developed. It has not been.

Another problem in developing temperature display devices is how to prevent erroneous display caused by noise generated by motorcycle engines and the like.

An object of the present invention is to provide an agricultural remote temperature display device that is inexpensive and can prevent erroneous display due to noise.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of the transmitter, and the transmitter is provided for each agricultural facility.

FIG. 2 is a block diagram of the receiver, which is installed at a central location such as a farmhouse.

In the transmitter, the temperature detection section TH detects the temperature of the agricultural facility, and the detected temperature is sent to the first timer circuit TM1.

As shown in FIG. 3, the first timer circuit TMI outputs a signal time T1 which is the sum of a time T'tt proportional to the detected temperature and a constant time T'to for distinguishing from noise.

The fixed time T'to is, for example, one second or more.

The second timer circuit TM2 sets a fixed time interval T2 for intermittently transmitting a signal wave.

The fixed time interval T2 is, for example, one minute.

The signal wave generation circuit 1 consists of a signal wave oscillator OSCI that generates a signal wave of an audio frequency, and an audio frequency filter LFl such as a reed filter or a mechanical filter, and generates a signal at a constant time interval T2 as shown in FIG. 4A. Signal wave 2 is generated for time T1.

Different audio frequencies are assigned to the signal waves for each agricultural facility.

For example, if 300 H2 to 6 KH2 are used as audio frequencies, different audio frequencies can be assigned to about 60 locations.

The frequency of carrier wave oscillator 08C2 is determined to be common to all agricultural facilities.

For example, a 40MH2 band is used.

The modulator MO modulates the carrier wave with the signal wave 2 to form a modulated wave 3, which is transmitted as a radio wave via a power amplifier AM1 and an antenna 4.

Note that the power amplifier AM1 and the antenna 4 constitute the transmitter of the present invention.

The transmitted radio waves are sent to the receiver's antenna 5 and high frequency amplifier A.
Received by M2.

The antenna 5 and the high frequency amplifier AM2 form the receiving section of the present invention.

The detector DT demodulates the received radio waves.

The demodulated signal wave is selected by an audio frequency filter LF2.

The audio frequency filter LF2 has as many detectors D as the number of agricultural facilities.
connected in parallel to the output side of the T, the audio frequency of which is matched to that assigned to each agricultural facility.

The signal wave that is the output of the audio frequency filter LF'2 is rectified by the rectifier circuit DC, and converted by the pulse conversion circuit PC into a number of pulses proportional to the signal time T1.

The subtraction circuit ST subtracts a number of pulses proportional to a certain time T'to for distinguishing from noise from the number of output pulses of the pulse conversion circuit PC, and outputs a number of pulses proportional to a time Tll proportional to temperature.

The number of output pulses from the subtraction circuit ST is counted by a counter CT, and the counted value is displayed as temperature.

Since the temperature is made proportional to time and transmitted wirelessly in this way, the temperature can be displayed remotely at low cost.

Since the noise generated by a motorcycle engine or the like is instantaneous, it is included within the fixed time T10, and this fixed time T'
Since to is cut by the subtraction circuit ST, erroneous display due to noise can be prevented.

Although the circuits after the audio frequency filter LF2 are provided separately for each agricultural facility, the antenna 5, high frequency amplifier AM2, and detector DT are commonly used for all agricultural facilities.

In addition, in the embodiment described above, the case of amplitude modulation was explained, but frequency modulation can also be used.

In this invention, a signal wave to which a different audio frequency is assigned to each agricultural facility is transmitted for a fixed period of time, which is the sum of a time proportional to the detected temperature and a fixed time to distinguish it from noise. This signal wave modulates a carrier wave with a frequency common to all agricultural facilities.
The modulated wave is transmitted as a radio wave, and a receiver at a central location extracts the signal time and converts it into a number of pulses proportional to the time, and from this number of pulses, a number of pulses proportional to a certain time to be distinguished from noise is determined. Since the subtraction is performed, the number of pulses after the subtraction is counted by a counter, and the counted value is displayed as temperature, the temperature can be displayed remotely at low cost.

Further, since noise is instantaneous, it is included within a certain time period to be distinguished from noise, and this amount is subtracted by the subtraction circuit.

Therefore, erroneous display due to noise can be prevented.

[Brief explanation of the drawing]

Figure 1 is a block diagram of an example of a transmitter according to the present invention;
The figure is a block diagram of an example of a receiver according to the present invention, FIG. 3 is a temperature-signal time characteristic diagram, and FIG. 4A. B is a waveform diagram of a signal wave and a modulated wave. 1... Signal generation circuit, 2... Signal wave,
3...Modulated wave, TH...Temperature detection section, TMl...First timer circuit, TM2...
...Second timer circuit, 08C2...Carrier wave oscillator, MO...Modulator, DT...Detector, LF2...Audio frequency filter, PC・・・
...Pulse conversion circuit, ST...Subtraction circuit,
CT...Counter.

Claims (1)

[Scope of utility model registration request] The transmitter consists of a transmitter installed at each agricultural facility and a receiver installed at a central location.The transmitter includes a temperature detection section that detects the temperature of the agricultural facility, and a time and noise proportional to the detected temperature. A first timer circuit outputs a signal time that is the sum of a certain period of time for distinguishing between agricultural facilities, and a second timer circuit sets a certain time interval for intermittently transmitting signal waves. a signal wave generation circuit that generates a signal wave to which an audio frequency is assigned for the signal time at the constant time interval; a carrier wave oscillator that generates a carrier wave of a frequency common to all agricultural facilities; The receiver includes a modulator that modulates the modulated wave as a radio wave, and a transmitter that transmits the modulated wave as a radio wave.The receiver includes a receiver that receives the radio wave from the transmitter, a detector that demodulates the received radio wave, and an audio frequency filter that selects the frequency of the signal wave, a pulse conversion circuit that converts the signal wave output from the audio frequency filter into a number of pulses proportional to the signal time, and a noise and noise filter that converts the signal wave output from the audio frequency filter into a number of pulses proportional to the signal time. A remote temperature display device for agriculture, comprising a subtraction circuit that subtracts the number of pulses proportional to a certain time for differentiation, and a counter that counts the number of output pulses of the subtraction circuit and displays the counted value as a temperature.