JPS6234589Y2 - - Google Patents

Description

[Detailed description of the invention] This invention uses an automatic moisture detection sensor that samples drying grains to detect the moisture value, and a hot air temperature detection sensor that detects the hot air temperature using an analog detection signal sent from each sensor. is connected to an AD conversion circuit that converts the signal into a digital detection signal and outputs it, compares the AD conversion circuit with the digital detection signal sent from the AD conversion circuit, and sends the result to the output side as an activation signal. This relates to an automatic control device for a grain drying device that is connected to a circuit and connected to the operating part of a drying unit such as a hot air supply device that generates hot air (drying air) on the output side of the control circuit. The purpose is to convert analog detection signals sent from an automatic moisture detection sensor that detects moisture value and a hot air temperature detection sensor that detects hot air temperature into digital detection signals using an AD conversion circuit, and then send the signals to the control circuit. The purpose of the present invention is to accurately convert analog detection signals sent from each sensor into digital detection signals and output them even if there is a fluctuation in the input power source of the AD conversion circuit when inputting the signals.

Next, to explain the embodiment in more detail based on the drawings, in FIG. 1, 1 is a grain drying device A.
The upper half of the inner cavity of the machine is equipped with a grain tank 10 into which grains to be dried are filled. Reference numeral 2 denotes a grain lifting machine installed on one side (front side) of the machine body 1 to load grain into the grain tank 10, and a bucket conveyor 21 endlessly installed in the inner cavity of the grain lifting tower 20. The lower end side of the grain lifting tower 20 is the terminal end in the transport direction of the lower conveyor 11 provided below the outlet at the bottom of the grain tank 10. The upper end side is connected to an upper conveyor 12 for feeding grains into the grain tank 10, and a take-out gutter 22 for taking out dried grains (not shown). (not). 3 is a hot air supply device that generates and supplies hot air (drying air);
It consists of a burner 30 that burns fuel supplied by a pump (electromagnetic pump), and a fan 31 that supplies hot air generated by the operation of the burner 30 to the grains. Alternatively, the fan 31 may be formed of a mesh body and communicated with the air guide path 13 installed in the aircraft body 1, and the fan 31 may be formed as a suction fan and communicated with an air exhaust path (not shown). By operating the fan 31, the burner 3
The hot air generated at 0 flows from the air guide path 13 to the grain tank 1.
0 (or the grain flow path), exits into the exhaust air path, and is discharged outside the machine.

The burner 30 is configured so that its operation is controlled by a solenoid valve (not shown) provided in a fuel pipe 33 communicating with the fuel tank 32 and the pump.

4, when drying the grains in the grain drying device A, sampling the grains being dried;
This is an automatic moisture detection sensor that detects the moisture value of the grain. The automatic moisture detection sensor 4 is shown in Figs. 3 and 4.
As shown in the figure, a take-out port 23 for taking out grains to be sampled is opened at the lower part of the grain lifting tower 20 of the grain lifting machine 2, and the take-out port 23 is inserted into the inner cavity of a case 24 attached to surround the take-out port 23. A guide gutter 40 is installed, which communicates with the guide gutter 40, and a pair of crushing rolls 41, 41 are supported below the guide gutter 40 so as to face each other and are driven and rotated by a motor M via a speed reduction device m, and
The circumferential surfaces of the crushing rolls 41, 41 are configured to serve as electrical contacts, respectively, and the crushing rolls 41,
The presence of the grains in the opposing gap between the crushing rolls 41 connects the crushing rolls 41 to the electric circuit to close the electric circuit. This type detects the moisture value by detecting the electric resistance value of the current flowing between the crushing rolls 41 and 41 during crushing, but the upper limit of the measurement range based on the electric resistance is It is set so that the measurement is carried out from about 24%, which is the moisture content of grains that do not cause crushed pieces to stick to the roll surface when crushed by 41, 41, to a moisture content with a lower limit of 12.5%. The intake port 23 to be sampled is equipped with a shutter 42 that opens and closes, and the shutter 42 is equipped with a solenoid 43 that operates at predetermined time intervals.
This opens the intake port 23 at regular intervals, and when the intake port 23 opens, a sampling operation is performed.

Reference numeral 5 denotes a hot air temperature detection sensor that detects the hot air temperature of the hot air sent by the hot air feeding device 3 using a thermistor. Hot air temperature detection sensor 5
The sensor is configured to detect the hot air temperature by reading the electrical resistance value which changes depending on the temperature, and as shown in FIG. The temperature sensing part (not shown) of No. 5 is facing. The mounting position of the hot air temperature detection sensor 5 may be set at any desired location as long as the temperature of the hot air (dry air) flowing in the air guide path 13 can be detected. It is installed at a position slightly away from the burner 30. 6
is an electronic switching circuit (multiplexer circuit), and for example, at the same time as detection by the automatic moisture detection sensor 4 starts, a command signal is input from a control circuit (described later). It is made into an IC circuit that outputs the detection signal to the output side, and its input terminals X ₁ , X ₂ , X ₃ , X ₄
is connected to the automatic moisture detection sensor 4, hot air temperature detection sensor 5, and variable resistors R, _R1 , and
An AD conversion circuit 7 is connected to the output terminal X. Note that one of the variable resistors R and _R1 is used to set the final moisture value of the grain determined by the automatic moisture detection sensor 4, and by changing its resistance value, In this embodiment, the lower limit can be set within a range from 12.5% to the upper limit 18.2%. Also, the other variable resistor R ₁
is for setting the hot air temperature by the hot air temperature detection sensor 5, and by changing its resistance value, in this embodiment, the minimum value is set within the range of 15°C to the maximum value of 75°C. I am trying to get it.

The AD conversion circuit 7 is an IC circuit that converts an analog detection signal into a digital detection signal. Its input terminal Y is connected to the output terminal X of the electronic switching circuit 6, and the analog detection signal sent from the circuit 6 is detected. It converts signals (moisture value and hot air temperature) into digital detection signals. Reference numeral 8 controls an operating section 9 of a grain working section such as a circulation motor (not shown) that drives the hot air supply device 3 or the bucket conveyor 21 based on the digital detection signal sent out from the AD conversion circuit 7. This is a control circuit that

The control circuit 8 is a program for issuing a command for the automatic moisture detection sensor 4 and the hot air temperature detection sensor 5 to periodically start measuring after a certain period of time, or for determining the moisture content of grains by the automatic moisture detection sensor 4. A program that sends a command signal to the electronic switching circuit 6 or the variable resistors R and _R1 so that the detection signal is output to the output terminal X side of the electronic switching circuit 6 at the same time as the measurement starts There is a program that compares and examines the detection signals from the automatic moisture detection sensor 4 and the hot air temperature detection sensor 5 based on the set final drying value (moisture value) of the grains or hot air temperature data and outputs an activation signal to the output side. For example, when the sensor 4 detects the grain moisture value (16%) set by the variable resistor R, the detected value is inputted via the electronic switching circuit 6 → AD conversion circuit 7. This provides a circuit from which an activation signal for stopping the activation section 9 of the hot air supply device 3 is sent.

Note that 44 is a filter circuit provided in the sensor circuit 45 of the automatic moisture detection sensor 4, and if immature grains with a high moisture content are mixed into the sampled grains, a high moisture value will be detected.
This is an IC for removing the moisture value of immature grains as an abnormal value.

Therefore, the power source of the automatic control device of the grain drying device configured as described above is supplied from the constant voltage circuit V.
Although the AD uses a 5V power supply, it converts analog signals into digital signals.
Since the conversion circuit 7 requires a stable power supply of 2V, a stable power supply (voltage) of 2V is secured by the reference voltage circuit 70 using the 5V power supply from the constant voltage circuit V. AD conversion circuit 7
is operated by the power from the reference voltage circuit 70, and is operated by the automatic moisture detection sensor 4 and the hot air temperature detection sensor 5.
When converting the detection signal (analog signal) from the controller into a digital detection signal, it is necessary to accurately convert the input analog signal into a digital signal and send it to the control circuit 8. At this time, if the power supply of the AD conversion circuit 7 and the power supply of each sensor 4, 5 that detects the moisture value or hot air temperature and the variable resistor R, _R1 that sets each moisture value/hot air temperature are separate, the power source When fluctuations occur, the reference power supply (voltage) becomes different, making it impossible to operate under the same conditions, resulting in inaccurate detection signals being output. It was hot.

Therefore, in this invention, the moisture value of the grains and the hot air temperature are connected to the reference voltage circuit 70 connected to the power supply terminal _Y1 of the AD conversion circuit 7 so as to supply input power to the AD conversion circuit ₇ . Setting value (resistance value)
In this embodiment, a means is proposed in which a power supply circuit 71 of an automatic moisture detection sensor 4 and a hot air temperature detection sensor 5 are connected.

By the above means, the AD conversion circuit 7, the variable resistors R and _R1 for setting the moisture value and the hot air temperature value, and the automatic moisture detection sensor 4 and the hot air temperature detection sensor 5.
Each power supply is operated by the power supply of the reference voltage circuit 70, so even if the power supply fluctuates, the AD
Conversion circuit 7, variable resistance R, _R1 , various sensors 4,
5, the operation is performed under the same changed conditions.

Therefore, according to this invention, the variable resistors R,
Since the power for R ₁ and the various sensors 4 and 5 is taken from the reference voltage circuit 70 that supplies power to the AD conversion circuit 7, even if there is a fluctuation in the power supply, the reference power supply changes at the same fluctuation ratio. In order to do this, they operate under the same conditions, and the detection signals detected by the sensors 4 and 5 can be converted into accurate digital signals by the AD conversion circuit 7.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a grain drying device implementing this invention, Figure 2 is a side view of the same as above, Figures 3 and 4 are cross-sectional views of an automatic moisture detection sensor, and Figure 5 is a block circuit. It is a diagram. Explanation of drawing symbols, A... Grain drying device, 1...
Aircraft body, 2... Grain frying machine, 3... Hot air supply device, 4...
...Automatic moisture detection sensor, 5...Hot air temperature detection sensor, 6...Electronic switching circuit, 7...AD conversion circuit,
8...Control circuit, 9...Drying action section,
R, R ₁ ...variable resistor, 70...reference voltage circuit,
71...Power supply circuit.

Claims (1)

[Scope of utility model registration request] The automatic moisture detection sensor samples drying grains and detects the moisture value, and the hot air temperature detection sensor detects the hot air temperature. Analog detection signals sent from each sensor are converted into digital detection signals and output. The AD conversion circuit is connected to a control circuit that compares the AD conversion circuit with a digital detection signal sent out from the AD conversion circuit and sends the result as an activation signal to the output side, and the output side of the control circuit In the automatic control device for a grain drying device in which the operating section of the drying section is connected to the AD
A reference voltage circuit is connected to the conversion circuit as an input power source of the circuit, and the reference voltage circuit is connected to a power supply circuit for various detection sensors that detect the moisture value of the grain and the hot air temperature based on the set value of the variable resistor. An automatic control device for a grain drying device, characterized in that: