JPH0419467B2 - - Google Patents

Description

Detailed Description of the Invention The present invention measures the moisture content of grains to be dried over time, detects the difference between the measured moisture value and a reference moisture value for each preset drying time, and calculates the hot air temperature. This invention relates to a grain drying method that performs controlled ventilation drying.

Conventionally, a grain drying control method in which drying is performed while correcting the temperature of hot air according to changes in the moisture content of the grain during drying is described in Japanese Patent Application Laid-Open No. 193082/1982. A method of continuing drying by resetting the hot air temperature based on the moisture information of the grain at that time is described in JP-A-58-72872.

By the way, as described in the above-mentioned Japanese Patent Application Laid-open No. 193082/1982, a drying control method that detects the moisture content of grains during drying and performs ventilation drying while correcting the temperature of the hot air according to the change in moisture content is used. For example, compared to a control means that continues drying with hot air at a temperature set at the start of drying, it is possible to perform appropriate drying control according to changes in grain moisture.

In addition, as described in the above-mentioned Japanese Patent Application Laid-open No. 58-72872, according to a method in which drying is continued by resetting the hot air temperature based on the moisture information of the grain at the end of drying, If moisture in the grain is detected correctly when resetting the temperature of the hot air, appropriate drying control will be possible.

However, in a grain dryer, the moisture content of the grain being dried is measured by extracting a very small amount of the grain, so the measurement sample may be a grain with a higher moisture content than the overall average value, or conversely a grain with a lower moisture content. When grains were used as measurement samples, the temperature of the hot air at the end of drying was not properly reset, which often caused shell cracking and insufficient drying.

The present invention solves these problems in conventional grain drying control methods, and at the end of drying, regardless of the moisture content of the grain during drying,
The purpose of the present invention is to provide a grain drying method that can obtain high-quality dried grain without causing shell cracking or insufficient drying by drying to the finished moisture value while maintaining the initial standard hot air temperature again. It is something to do.

Next, an embodiment of the present invention will be described with reference to an example of an apparatus shown in the drawings.

In FIG. 1, 1 is a hot air temperature detector, 2 is a reference hot air temperature setting circuit, and 3 is a temperature comparison circuit.
Further, 4 is a moisture measuring device, 5 is a reference moisture value setting circuit, and 6 is a moisture comparison circuit.
The output is input to the control pattern switching circuit 7 and sent to the temperature comparison circuit 3, so as to correct the set value of the hot air temperature. 8 is a hot air temperature control circuit, and 9 is a fuel supply pump. The hot air temperature control circuit 8 receives the corrected control signal from the temperature comparison circuit 3 and controls the fuel supply pump 9.

The reference hot air temperature setting circuit 2 is for setting a reference hot air temperature at the initial stage of drying, and the reference moisture value setting circuit 5 is for setting a reference moisture value in advance. Furthermore, the control pattern switching circuit 7 does not send its input to the temperature comparison circuit 3 until a certain drying time has elapsed from the start of drying, and after that, the measured moisture value approaches a certain value at the end of drying (for example, 16 %), the input is sent to temperature comparison circuit 3.
In addition, then the finish moisture value (e.g. 15
%), the input is again sent to temperature comparison circuit 3.
It operates in such a way that it is not sent to

In the apparatus configured as described above, at the start of drying, depending on the amount of grain loaded, the outside temperature, etc.
A reference hot air temperature is determined, and drying is performed while maintaining that hot air temperature. And the control pattern switching circuit 7
By this operation, the hot air temperature is controlled in a preset temperature range according to the difference between the measured moisture value and the preset moisture value until the moisture value is slightly higher than the finished drying moisture value, and drying continues. When reaching the final stage,
The initial standard hot air temperature is maintained again to dry to the final moisture value. Therefore, regardless of the measured moisture value of the grain during drying, it is possible to dry the grain without causing shell cracking or insufficient drying.

As described above, the present invention maintains the standard hot air temperature set at the beginning of drying in the initial stage of drying, and then maintains the measured moisture value and the preset moisture value until the moisture value is slightly higher than the finished drying moisture value. After drying by controlling the hot air temperature in a preset temperature range according to the difference, the initial reference hot air temperature is maintained again at the end of the drying period to dry to the finished moisture value. Regardless of the measured moisture value of the grain during drying, by maintaining the initial standard hot air temperature again and drying to the finished moisture value, high quality dried grain can be obtained without causing shell cracking or insufficient drying. It produces the effect that can be achieved.

[Brief explanation of drawings]

The drawings show an embodiment of the apparatus for carrying out the grain drying method according to the present invention, in which FIG. 1 is a block diagram showing the main parts of the structure, and FIG. 2 is an explanatory diagram of its operation. 1...Hot air temperature detector, 2...Reference hot air temperature setting circuit, 3...Temperature comparison circuit, 4...Moisture measuring device, 5...Reference moisture value setting circuit, 6...Moisture content comparison circuit, 7... Control pattern switching circuit, 8... hot air temperature control circuit, 9... fuel supply pump.

Claims (1)

[Claims] 1. In the initial stage of drying, drying is carried out by maintaining the reference hot air temperature set at the start of drying, and then, until the moisture value is slightly higher than the dry finish moisture value, the temperature is set in advance according to the difference between the measured moisture value and the preset moisture value. This grain drying method is characterized in that after drying by controlling the hot air temperature according to the grain width, the initial standard hot air temperature is maintained again at the end of the drying period to dry the grain to a finishing moisture value.