JPH0451754B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a grain drying apparatus, and more particularly to a grain drying apparatus that temporarily stops drying in the middle of drying in order to utilize the tempering effect.

[Technical Background of the Invention and Problems Therewith] Conventional grain drying devices operate by inputting the amount of grain to be loaded into a grain tank, the type of grain to be loaded, and a target moisture value on the operator side. The device itself automatically calculates a target drying temperature, and automatically controls the combustion device and others so that the actual temperature matches the target drying temperature, thereby drying the grain. Once the target drying temperature is set, the machine will always dry the grain continuously unless the operator stops the machine himself.
There was no pause in the middle.

However, when forcing grain to dry,
In general, it is known from experience that grain cracking is more likely to occur when the moisture content of grain reaches around 20%. This is thought to be due to the large difference in moisture content between the surface and inside of each grain of grain. Therefore, if we stop drying for a certain period of time when the moisture content reaches around 20% and take care to equalize the moisture content inside and outside of each grain through the tempering effect, we can then start drying again. Even if the process is restarted, the shell cracking phenomenon will be less likely to occur. However, in the conventional grain drying apparatus, no consideration was given to providing a drying pause time during the drying process.
For this reason, it has not been possible to completely prevent shell cracking during automatic grain drying, and improvements have been desired in terms of quality.

[Purpose of the Invention] The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide a grain drying device that can prevent grain shell cracking and dry grain with good quality. do.

[Summary of the Invention] The present invention provides calculation means for obtaining initial moisture value data of grains in a grain tank and calculating drying rest time, moisture value measuring means for monitoring the moisture value of grains during drying, and comprising a control means for suspending drying for a time set by the calculation means when the moisture value data from the value measurement means reaches a predetermined moisture value;
The drying pause time is determined based on the initial moisture value of the grain that is poured into the grain tank, and the drying pause is performed for the optimal drying pause time depending on the initial moisture value, when the moisture level reaches the predetermined moisture value. This is a grain drying device that prevents shell cracking and other problems and improves quality.

Further, in the second invention, there is provided a calculation means for obtaining initial moisture value data of the grain in the grain tank and calculating a drying pause start moisture value, and a moisture value measuring means for monitoring the moisture value of the grain during drying. A control means is provided for suspending drying for a predetermined time when the moisture value data from the moisture value measuring means reaches the drying pause start moisture value set by the calculation means, and the drying is suspended according to the initial moisture value of the grain. This grain dryer is capable of preventing shell cracking and performing high-quality drying by setting a starting moisture value and stopping drying for a predetermined time at the moisture value most suitable for preventing shell cracking.

[Embodiments of the Invention] Hereinafter, embodiments of the present invention will be explained in detail based on the drawings. 2 to 4 show the mechanical structure of a grain drying apparatus according to an embodiment of the present invention. This grain drying device is equipped with a combustion device 2 at the front of a grain tank 1, an air conditioning fan 3 at the rear,
Furthermore, an operation box 4 for controlling each device is provided at the front of the grain tank 1. Also provided are a fuel tank 5, a fuel supply pipe 6, an electromagnetic pump 7, and an electromagnetic valve 8 for supplying fuel to the combustion device 2. Furthermore, the grain tank 1 is equipped with an elevator 10 for returning the grain 9 sent from the lower part to the upper part of the grain tank 1.

The inside of the grain tank 1 will be explained in detail with reference to FIGS. 3 and 4. An upper screw conveyor 12 and a spreading device 13 are provided in the upper part of the storage chamber 11. Further, the lower part of the storage chamber 11 is formed in the shape of a funnel, and the lower end of the funnel part 14 is connected to the upper end of a flowing drying chamber 15. Said pair of left and right drying chambers 1
A hot air supply chamber 16 is formed between 5 and 15, and a hot air drying chamber 17 is formed outside the drying chamber 15, respectively. At the lower end of the drying chamber 15, there is provided a rotary valve 18 for adjusting the amount of grain 9 flowing down. 20 is formed. Said receiving gutter 19
A lower screw conveyor 21 is installed in the center of the conveyor belt.

The grains 9 thus filled in the storage chamber 11 flow down the funnel portion 14 and are collected in the shell collection chamber 20 by the rotary valve 18. In the grain collection chamber 20, the grains are sent horizontally to the outside by a lower screw conveyor 21, and then returned to the upper screw conveyor 12 at the upper part of the grain tank 1 by an elevator 10. Then, the grains 9 are fed in the front and back direction on this upper screw conveyor 12, and are loaded into the storage chamber 11 again while being uniformly spread left and right by a spreading device 13 at the bottom thereof.

FIG. 4 shows a cross-sectional view taken along the line -- in FIG. be. Further, an exhaust pipe 23 is attached to the exhaust side, which is the rear end of the hot air drying chamber 17, and an air conditioning fan 3 with a variable rotation speed is attached inside the exhaust pipe 23. When the air conditioning fan 3 rotates, the hot air from the combustion device 2 side flows into the hot air supply chamber 1 as shown by the arrow.
6. Passing through the drying chamber 15 to the hot air drying chamber 17,
The hot air is circulated so as to be exhausted to the outside through the exhaust pipe 23.

The amount of fuel supplied from the fuel tank 5 to the combustion device 2 in FIG. 2 is controlled by controlling the on-time of the rectangular pulse wave applied to the electromagnetic valve 8. By controlling the combustion temperature depending on the magnitude of the fuel flow rate, the temperature of the hot air supplied to the drying chamber 15 can be changed.

In addition, operation box 4 has a tension setting knob,
A target moisture setting knob, a power switch, a pilot lamp, a display section 4a, a drying time setting keyboard 4b, and other necessary input operation means are centrally provided.

In such a grain drying apparatus, the actual temperature control of the drying chamber 15 is performed by a microcomputer 100 shown in FIG. This microcomputer 100 includes a memory 101 and a CPU 102 as a calculation means. Then, the operation unit 103 connects the digital input circuit via 104.
Further, the analog input section 105 is connected to the A/D converter 106.
is connected as input information via. Further, a mechanical drive system 107 and a temperature control system 109 are connected to the output section via an amplifier circuit 108 and an amplifier circuit 110, respectively. Further, a digital display section 111 is connected via an amplifier circuit 112.

In the operation section 103, a set temperature call button 113, a filling start button 114, a drying start button 115, and a discharge start button 116 are provided as push buttons, respectively, and a switch 117 for setting the filling amount and a grain type setting switch 117 are provided. A switch 118 and a target moisture value setting switch 119 are each provided as a rotary switch. A group of safety sensors 120 such as a heating sensor, a paddy clogging sensor, and a full warning sensor are also provided.

As the analog input section 105, a hot air temperature sensor 121, an outside air temperature sensor 122, and a moisture meter 123 are provided.

The mechanical drive system 107 includes an elevator motor, a fan motor, a rotary valve motor, a fuel pump,
Contains the ignition heater ON-OFF signal.

Furthermore, the temperature control system 109 includes a fuel control valve.
It includes ON-OFF signals and the drive signal for the air conditioning fan motor. The drive signal for the air conditioning fan motor is obtained by inputting the ON-OFF signal of the fuel control valve into the fuel control signal smoothing circuit 124, and further controlling the rotation speed of the fan motor by the motor rotation speed control circuit 125. It is designed to be a rotational drive signal.

Note that the oscillation circuit 126 provides a clock signal to the microcomputer 100.

The operation of the grain drying apparatus having the above structure will be explained based on the flowchart in FIG. 5 and the time charts in FIGS. 6 and 7. By operating the tensioning button 114, grain tensioning is first started. After the pasting is completed, the drying button 115 is set. In order to set the input data, a switch 117 for setting the filling amount and a switch 11 for setting the grain type are operated.
8. Set the target moisture value setting switch 119 to a predetermined position. The microcomputer 100 reads the above input set, performs calculations, and sets a target drying temperature. Additionally, the mechanical drive system 107 is operated to start drying. In this way, the drying operation is started. (Steps 31 and 32) After the drying operation starts, the analog input section 105
The hot air temperature sensor 121, the outside air temperature sensor 122, and the moisture meter 123 each periodically input measurement data to the microcomputer 100, and the data is stored in the memory 101. Immediately after the start of drying, the moisture value measured by the moisture meter 123 is taken in as the initial moisture value M ₀ and stored in the memory 101. (Step 33) Then, the drying pause time T _S is calculated from this initial moisture value M ₀ based on the graph shown in FIG. (Step 34) Here, the relationship between the initial moisture value M ₀ and the drying pause time T _S is set so that the higher the initial moisture value M ₀ is, the longer the drying pause time T _S is, as shown in FIG. For example, when M ₀ is 26% or more, T _S is 2 hours, and when M ₀ is between 24% and 26%, T _S is
1.5 hours, and when M ₀ is 22% to 24%, T _S is 1 hour. If the initial moisture value M ₀ is less than 22%, the drying pause time T _S is set to 0. It is assumed that the relationship between the initial moisture value M ₀ and the drying pause time T _S is stored in the memory 101 in advance.

After drying starts, the actual temperature in the drying chamber is automatically controlled to match the target temperature. Its operation is as follows. In other words, the actual temperature in the drying chamber from the hot air temperature sensor 121 is read and compared with the target drying temperature, and if the actual temperature is lower than the target temperature, the CPU 102 causes the solenoid valve 8 to lengthen the on-time period. emit a control signal;
At the same time, the Bona air conditioning fan motor also operates to increase its rotational speed, thereby increasing the combustion temperature of the combustion device 2 and increasing the hot air temperature. Conversely, if the actual temperature is higher than the target temperature,
The CPU 102 shortens the on-time period of the electromagnetic valve 8 and at the same time suppresses the rotation speed of the burner air conditioning fan motor, thereby lowering the hot air temperature. In this way, during the drying operation, the temperature of the hot air is automatically controlled to keep it almost constant.

While the drying operation continues in this manner, the moisture value M _R from the moisture meter 123 is periodically read and compared with the drying pause start moisture value M _T . (step
35, 36) The drying pause start moisture value M _T set here is M T = M _T = It is desirable to set it to 20%.
Then, the actual moisture value M _R is the drying pause start moisture value M _T
A drying pause begins when . (Steps 37 and 38) Here, in step 37, it is determined whether the pause time is 0 or not because the initial moisture value M ₀ is less than 22%, and it is determined whether or not to perform an intermediate drying pause. This is to do so.

If a drying pause starts, the drying is paused until the drying pause time T _S calculated in step 34 has elapsed. (Step 39) Due to this drying pause state, the tempering effect makes the gradient of the moisture value uniform between the inside and the surface of the grain, making it difficult for shell cracking to occur.

After the drying pause time T _S time has elapsed, the drying operation is started again. (Step 40) The moisture value _MR of the grain is read periodically and compared to see if it has reached the target moisture value _MF , and when the target moisture value _MF is reached, the drying operation is stopped. (Steps 41-43) In this way, the intermediate drying pause time T _S can be made variable depending on the initial moisture value M ₀ of the grain, and cracking of the grain shell can be effectively prevented.

An embodiment of the second invention will be described next. The circuit configuration of this embodiment of the second invention is similar to the embodiment of the first invention, and has the configuration shown in FIG. However, the only operational difference is the arithmetic processing in the CPU 102. That is, in this embodiment of the second invention, the CPU 102 changes the drying pause start moisture value M _S as shown in FIG. 9 based on the initial moisture value M ₀ of the grain obtained from the moisture meter 123.

Next, the operation will be explained based on the flowchart shown in FIG. switch 117 for setting the amount of filling;
The grain type setting switch 118 and the target moisture value setting switch 119 are operated to set input data, and the drying button 115 is pressed to start drying. (Steps 51 and 52) Here, by operating the drying start button 115, the microcomputer 100 starts the mechanical drive system 10 as in the above embodiment.
Operate 7. The temperature control system 109 is also operated to automatically control the hot air temperature to match the target temperature. When the drying operation starts, the hot air temperature sensor 121, outside air temperature sensor 122, and moisture meter 123 in the analog input 105 each periodically input measurement data to the microcomputer 100 and store it in the memory 101. At the same time, the initial moisture value of the grain measured by the moisture meter 123 is stored in the memory 101 as an initial moisture value M ₀ .
(Step 53) After obtaining the initial moisture value M ₀ , the CPU 102 calculates the initial moisture value M 0 measured from the initial moisture value M ₀ -drying pause start moisture value M _S relationship graph as shown in FIG. 9 stored in the memory 101. A drying pause start moisture value M _S corresponding to the moisture value M ₀ is calculated. (Step 54) The relationship between M ₀ - M _S in this FIG. 9 is, for example, when M ₀ is
When it is 28% or more, M _S is 22% and M ₀ is 25-28%.
When M _S is 21%, when M ₀ is 22-25%, M _S is 20
%, and when _M0 is less than 22%, it is set not to pause midway.

Next, it is determined whether the initial moisture value M ₀ is so low that an intermediate pause is not necessary (step 55), and if an intermediate pause is necessary, the moisture value M _R is periodically read from the memory 101 and a drying pause is started. Compare whether the moisture value has reached M _S. (Steps 56 and 57) Here, the grain moisture value M _R is the drying pause start moisture value.
Grain drying will continue until M _S is reached.

When the moisture value M _R reaches the drying pause start moisture value M _S , a temporary pause in drying is started. (Step 58)
Once this temporary drying pause begins, the pause continues for a preset certain period of time, for example, one to two hours. (Step 59) Here, the drying rest time T _R may be set uniformly regardless of the initial moisture value M ₀ , or the drying rest time T R may be set uniformly regardless of the initial moisture value M ₀ .
The length may be variable depending on the situation.

When the drying pause time _elapses , the drying operation is restarted. (Step 60) After this, the drying operation is continued until the actual moisture value _MR of the grain reaches the initially set target moisture value _MF , and is completed when the target moisture value _MF is reached. (Steps 61-63) Also in this embodiment of the second invention, the actual drying temperature in the drying chamber 15 during the drying operation is
The temperature is always controlled so as to match the target drying temperature calculated using This is done depending on the length of time.

[Effects of the Invention] As described above, this invention allows the drying pause time to be varied depending on the initial moisture value of the grain. The large difference in the moisture gradient inside the grain can be evened out by extending the resting time, the tempering effect can be fully utilized, and grain cracking can be effectively prevented. Furthermore, the tempering effect allows for a large amount of moisture to be removed during drying of the material, making it possible to perform efficient drying.

Furthermore, in the second invention, since the drying pause start moisture value is changed according to the initial moisture value, the drying pause starts when the moisture value reaches a certain value regardless of the initial moisture value. Even for grains that have a high initial moisture value and are prone to shell cracking due to a large gradient in moisture values between the inside and the surface, the risk of shell cracking can be prevented by increasing the moisture value at the start of drying. Therefore, it has the advantage that grains having any initial moisture value can be efficiently dried without causing shell cracking.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a perspective view of the same embodiment, FIG. 3 is a front sectional view of the same embodiment, and FIG. 4 is a sectional view taken along the - line in FIG. 3. Fig. 5 is a flowchart of the operation of the above embodiment, and Fig. 6 is an initial moisture value used in the above embodiment.
Drying pause time relationship diagram, Figure 7 is an operation timing chart of the mechanical drive system of the same embodiment as above, and Figure 8 is the second diagram.
FIG. 9, which is an operational flowchart of an embodiment of the invention, is a relationship between the initial moisture value and the drying pause start moisture value used in the above embodiment. 1...Grain tank, 2...Combustion device, 3...Air conditioning fan, 4...Operation box, 5...Fuel tank, 7...Electromagnetic pump, 8...Solenoid valve, 9...
...Grain, 10...Elevator, 11...Storage room,
15...Drying room, 16...Hot air supply room, 17...
Hot air drying chamber, 18...Rotary valve, 100...Microcomputer, 101...Memory, 102
... CPU, 103 ... Operation section, 105 ... Analog input section, 107 ... Mechanical drive system, 109 ...
Temperature control system, 111...display section, 123...moisture meter.

Claims (1)

[Scope of Claims] 1. Calculating means for obtaining initial moisture value data of grain in a grain tank and calculating drying rest time, moisture value measuring means for monitoring moisture value of grain during drying, and moisture value measurement for this moisture value measurement. A grain drying apparatus comprising control means for suspending drying for a time set by the calculation means when moisture value data from the means reaches a predetermined moisture value. 2. Calculating means for obtaining initial moisture value data of the grain in the grain tank and calculating the drying pause start moisture value, moisture value measuring means for monitoring the moisture value of the grain during drying, and moisture value measuring means for monitoring the moisture value of the grain during drying. A grain drying apparatus comprising a control means for suspending drying for a predetermined time when the value data reaches a drying suspension start moisture value set by the calculation means.