JPS622679B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drying control method and device for a grain dryer, and in particular, the moisture value of grain in the grain flow path of the drying section is sequentially measured by a moisture meter, and the maximum drying reduction is determined by feedback control. In addition to effectively drying grains to a certain level to prevent grain quality deterioration, it also shortens the total drying time to prevent loss of power and thermal energy.
Moreover, the present invention relates to a drying control method and apparatus for a grain dryer that can reduce noise generation.

Conventionally, grain driers have been configured so that once drying operation is started, the drying operation is not stopped midway through, but continues to be operated until the grain to be dried reaches a set moisture value. If the drying rate is unnecessarily high, the grains will crack, so a lower drying loss rate was determined by measuring the moisture content just before the drying section, which inevitably resulted in a long drying time. It is inefficient. Furthermore, since the grain dryer is operated for a long time, power loss occurs and thermal energy is wasted in the drying section. Furthermore, since the feed valve and various motors for conveyance are driven continuously during the operation of the dryer, there is an inconvenience that noise pollution occurs.

Therefore, the purpose of the present invention is to eliminate the above-mentioned disadvantages, to successively measure the moisture value of the grain in the grain flow path of the drying section using a moisture meter, and to perform effective drying to the maximum drying loss rate value by feedback control. To provide a drying control method and device for a grain dryer which can prevent quality deterioration of grain, shorten total drying time to prevent loss of power and thermal energy, and reduce noise generation.

In order to achieve this object, the present invention provides a moisture meter for measuring the grain moisture value in the grain flow path of the drying section, and measures the initial grain moisture content at the beginning of grain flow into the grain flow path of the drying section. a drying rate setting step in which a calculation means calculates a maximum drying rate value for one pass based on the drying rate data stored in advance in the storage means and the drying rate data stored in advance in the storage means; At the same time, the initial grain moisture value measured after the initial flow of the grain into the grain flow path of the drying section is compared with the initial grain moisture value by a comparing means to determine whether the grain has reached the maximum dryness of the one pass. a drying confirmation step of detecting whether or not the grain has been dried to a drying loss rate value; and driving the feeding valve according to a command from the comparison means at the time when it is detected that the grain has been dried to the maximum drying loss rate value of the one pass. The method is characterized in that the drying is performed by sequentially drying and returning the grains to the discharge and replacement step of discharging and replacing the grains in the drying section by means of a valve drive control means.

In addition, a moisture meter that measures the grain moisture value in the grain flow path of the drying section and outputs a detection signal, and a moisture meter that stores in advance the initial grain moisture value measured at the initial stage when the grain flows into the grain flow path of the drying section. a calculating means for calculating a maximum drying loss rate value for one pass based on the drying loss rate data stored in the means; Comparing means for detecting whether or not the grain has dried to the maximum drying rate value of the one pass by comparing the initial grain moisture value with the initial grain moisture value measured after the initial flow of the grain into the grain channel. and a valve drive for driving the feeding valve for a predetermined period of time in response to a command from the comparing means at the time when it is detected that the grain has dried to the maximum drying loss rate value of the one pass, and discharging and replacing the grain in the drying section. It is characterized by comprising a control means.

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

1 to 3 show a first embodiment of the invention. In the figure, 2 is a grain dryer. This grain dryer 2 has a storage section 4, a drying section 6, and a grain collecting section 8, and lifts up the grains put into a supply hopper (not shown) of the grain lifting machine, and transports the grains by an upper conveying means 10. It is transported to the upper center of the dryer 2 and stored in the storage section 4.
The material is placed in the storage section 4 while dropping an equal amount into the container. Then, during the drying operation process, the grains are transferred to the drying section 6.
After being exposed to hot air, the grains are guided to the collecting section 8, transferred to the lower part of the grain lifting machine by the vertical conveying means 12, then lifted up by the grain raising machine, and then distributed equally into the storage section 4 by the upper conveying means 10 again. Grain is dried by repeating the cycle of dropping it.

A moisture meter 16 is provided midway through the grain flow path 14 of the drying section 6 to measure the moisture content of the grain in the grain flow path 14 and output a detection signal. At the lower part of the grain flow path 14, the outlet 20 of the feeding path 18 connected to the grain collecting section 8 is opened and terminated. The outlet 20 has rotary delivery valves 22-1, 22-2, 22-3, 22-
4, and an endless chain 30 is wound between the driven sprocket 24 of each delivery valve 22 and the driving sprocket 28 of the lower circulation motor 26, and a cradle is created between each driven sprocket 24 via the guide sprocket 32. Ensure the desired direction of rotation. A geared motor (electric motor with a reduction gear) is used as the lower circulation motor 26, and the circulation speed, that is, the amount of feeding is variable by controlling the timing of activation and stop of the geared motor. A vertical conveying means 12 consisting of a screw conveyor or the like is provided on the ridgeline at the lower end of the grain collecting section 8.

Next, the control circuit will be explained based on the block diagram shown in FIG.

In FIG. 2, 42 is an outside air humidity sensor, 44
is an outside air temperature sensor, 46 is a hot air temperature sensor, 48
50 is a grain amount setting switch, 52 is an operation switch, and 54 is a stop switch.

Further, 56 is a group of various safety switches, such as a fire extinguisher operating switch, a grain lifting machine switch, and a combustion overflow switch.

58 is a clock oscillator, 60 is an A/D conversion circuit, 62 is an encoder, and 64 is a
It is a control microcomputer consisting mainly of a CPU (central processing unit). This microcomputer 64 calculates the maximum drying rate of one pass based on the initial grain moisture value measured at the initial stage when the grain flows into the grain flow path 14 of the drying section 6 and the drying loss rate data stored in advance in the storage means. a calculation means for calculating a reduction rate value;
Drying is continued while at least the driving of the grain delivery valve 22 is stopped, and the initial grain moisture value is compared with the initial grain moisture value measured after the initial flow of the grain into the grain flow path 14 of the drying section 6. a comparison means for detecting whether the grain has been dried to the maximum drying loss value of the one pass; and a comparison means for detecting whether the grain has dried to the maximum drying loss value of the one pass. It has a valve drive control means that drives the feeding valve 22 for a predetermined period of time in response to a command to discharge and replace the grains in the drying section 6.

Further, 66 is a monitor display, and this monitor display 66 displays the safety state of the dryer. 68 is a numerical display, and this numerical display 68 is the moisture meter 1.
The grain moisture value detected in step 6 and the hot air temperature are alternately displayed digitally. 70 is a burner drive circuit, 72
is the motor drive circuit, and the microcomputer 64
The respective loads are driven according to data from the output data buffers inside. That is, the burner drive circuit 7
0 controls and drives the ignition heater 74, the ignition valve 76, the pump 78, and the burner fan motor 80. The motor drive circuit 72 also includes a conveyor motor 82, an exhaust fan motor 84, and a dust remover motor 8.
6. Lower circulation motor 26, upper circulation motor 3
8, and controls and drives the moisture meter motor 88. In addition, since the burner is not extinguished during drying, not only a gun-type burner but also a pot-type burner can be used.

Next, the operation will be explained based on the flowchart of FIG.

When the operation switch 52 of the grain dryer 2 is turned on, the program starts and enters the start state 100. Next, the conveyor motor 82 and the exhaust fan motor 84 are in the ON102 state. When the grain flow path 14 of the drying section 6 is filled with grain, detected values from various sensors are inputted 104. That is, the initial grain moisture value M ₁ that is initially measured on the grain flowing into the grain flow path 14 of the drying section 6 from the moisture meter 16, the outside air humidity HD from the outside air humidity sensor 42, and the outside air temperature sensor 44
from the outside air temperature Ta, the hot air temperature Tb from the hot air temperature sensor 46, and the stop moisture value setting temperature switch 4.
The stop moisture value Ms is input from 8, and the grain amount C is input from the grain amount setting switch 50.

Next, the initial grain moisture value M ₁ obtained from the moisture meter 16 and the stop moisture value Ms are compared 106, and when the initial grain moisture value M ₁ reaches the stop moisture value Ms, that is,
If YES, the burner drive control circuit 70 turns the burner extinguishing temperature control OFF 108, stops the various motors 110, and enters the state of drying completion 112.

On the other hand, if the initial grain moisture value M ₁ has not reached the stop moisture value Ms, that is, in the case of NO, it is determined based on the values input from the above-mentioned various sensors that grain grains are not cracked and are efficiently processed. Set temperature to achieve a good drying rate F%/H for drying.
The calculation 114 of Tc is performed by the microcomputer 64. After the calculation 114 of this set temperature Tc is completed, the calculation ₁₁₆ of the maximum drying rate value Me of one pass, which is determined within a range where the grain does not cause shell cracking, etc., is then carried out in accordance with the measured initial grain moisture value M1. is performed in the drying loss rate setting process. That is, the determination of the maximum drying loss value Me for one pass is automatically calculated by the calculating means based on drying rate data such as experimental data stored in advance in the storage means. Next, the driving of at least the lower circulation motor 26 is stopped, and the driving of the delivery valve 22 is stopped. At this time, in order to continue drying the grain, the burner drive circuit 70 is activated, the ignition heater 74 is turned on, the ignition valve 76 is opened for a predetermined period of time, and the burner fan heater 80 is driven while the pump 78 is supplying oil. Then, ignite the burner and set the temperature control to ON118. Next, after a predetermined period of time has elapsed, moisture measurement 120 is performed using the moisture meter 16 to measure the initial grain moisture value M ₂ .

Next, the comparison means compares the initial grain moisture value M ₂ measured after the initial flow of the grain into the grain flow section 14 with the initial grain moisture value M ₁ , and the grain reaches the maximum drying loss rate value of the one pass. It is detected in the drying confirmation step whether or not the drying process has been completed. That is, a comparison judgment 122 is made to determine whether the maximum drying loss rate value Me for one pass is M ₁ - M ₂ ≧Me, and if NO, that is, if the maximum drying loss rate value has not been reached, the burner ignition temperature is control
Jump ON118 to continue drying. During this jump, the burner is already ignited, so no burner ignition is performed.

Next, if the comparison judgment 122 is YES, that is, if the maximum drying loss rate value has been reached, the discharge timer Te 124 is set to a predetermined time, and then,
Based on a command from the comparison means at the time when it is detected that the grain has dried to the maximum drying loss rate value of the one pass,
The lower circulation motor 26 is turned on for a predetermined period of time. When this lower circulation motor 26 is driven, as shown in FIG.
22-2, 22-3, and 22-4 are intermittently driven via an endless chain 30 to feed grain.

Next, the set discharge timer Te12
4 is over, is judged 128, and if NO, the lower circulation motor 2 is controlled by the valve drive control means.
6 continues to be driven, and in the case of YES, the lower circulation motor 26 is turned OFF 130 to complete discharging the grains in the drying section 6. Then, for the next stage of drying, the process jumps again to the input 104 of detected values from various sensors. When the grain discharge is completed, the driving of the feeding valve 22 is stopped and the next undried grain is supplied to the drying section 6. Grain drying is then carried out by sequentially repeating such a grain discharge/replacement step.

As a result, as shown in FIG. 6, the normal drying (the graph shown by the solid line) required time T ₁ to dry to the desired stop moisture value (Ms), but the drying according to the present invention (the graph shown by the dotted line) ), the required time T ₂ is sufficient, and by shortening the time T ₃ , the total drying time can be shortened, the drying work can be completed quickly, and ideal drying can be achieved without causing cracks or the like. can be accomplished. Since the total drying time can be shortened in this way, the operation time of the grain dryer can be shortened to prevent power loss, as well as thermal energy loss in the drying section, and noise generation can also be reduced. It can be reduced as much as possible.

Further, in general, the maximum drying loss rate that can be tolerated to prevent grain quality deterioration gradually decreases as the moisture value of the grain decreases. Therefore, in this embodiment, the drying rate data of the decreasing characteristic of the maximum drying rate of grain is stored in advance in the storage means, and the maximum drying rate value is calculated based on this drying rate data and the initial grain moisture value. Since the configuration is automatically set, the drying loss rate is changed according to the decreasing change in the moisture value, and grains can always be highly efficiently dried at the maximum drying loss rate value that does not cause quality deterioration.

Furthermore, the moisture value of the grains is directly measured while stopping the feeding of the grains in the grain flow section 14 of the drying section 6, and when the moisture value of the grains has decreased to a value minus the maximum drying loss rate value, the moisture value of the grains is measured. Since the discharge is performed, there is no delay in control response, and grain quality can be maintained at a good level.

4 and 5 show a second embodiment of the invention. In the following embodiments, parts having the same functions as those in the first embodiment described above are given the same reference numerals and explained.

This second embodiment is characterized by the following points. That is, as shown in FIG. 4, a preheating section 34 is provided between the storage section 4 and the drying section 6, and a rotary type upper delivery valve 36 is provided at the bottom of the preheating section 34.
1, 36-2, 36-3, 36-4, and an upper circulation motor 3 that drives this delivery valve 36.
8 and an endless chain 39, and a full amount sensor 40 for detecting whether or not the drying section 6 is full is provided.

Hereinafter, the operation of this second embodiment will be explained based on the flowchart of FIG. 5.

The upper circulation motor 38 and the full sensor 40 are controlled between the motor drive 102 and the detected value input 104. That is, when the operation switch 52 is turned on,
The upper circulation motor 38 is turned on 132 together with the motor drive 102, and then the full quantity sensor 40 is turned on.
becomes ON134. This full amount sensor 40 is NO.
In the case of , that is, when the grain is not sufficiently loaded into the drying section 6, the circulation motor 38 continues to rotate, and when the quantity is full and the state becomes YES, the circulation motor 38 becomes OFF136.

Next, input 104 detection values from various sensors.
Also, in particular, burner extinguishing temperature control OFF108
is performed between the comparison determination 122 and the discharge timer 124.
That is, after drying is completed and when the dried grains are discharged, burner extinguishing temperature control OFF 108 is performed to prevent thermal energy loss due to blow-through. Incidentally, since it is necessary to repeatedly ignite and extinguish the burner alternately for a short period of time, a gun-type burner is used in this second embodiment.

If configured as in the second embodiment, since the preheating section 34 is provided between the storage section 4 and the drying section 6, the grains are preheated and heated in this preheating section 34, and the heated grains are transferred to the drying section 6. Since it flows into the section 6, effective drying can be achieved.

Further, since the upper delivery valve 36 is provided at the lower part of the preheating section 34, the lower delivery valve 22 is opened after drying is completed to completely discharge the dried grains, and then the upper delivery valve 36 is controlled to be opened. be able to. Thereby, dried grains and undried grains can be completely separated, and uniform drying can be easily achieved in the drying section 6. Furthermore, since the burner extinguishing temperature control OFF 108 is performed after the comparison and determination 122, it is possible to avoid loss of thermal energy due to hot air blowing through without wasting unnecessary power.

As is clear from the above description, according to the present invention, the following effects are obtained.

(1) Calculate the maximum drying rate value for one pass based on the initial grain moisture value measured at the beginning of the grain flow into the grain flow path of the drying section and the drying rate data stored in advance in the storage means. The drying is continued while at least the drive of the feeding valve is stopped, and the initial grain moisture value is compared with the initial grain moisture value after a predetermined period of time to determine the maximum drying loss of the grain in one pass. By detecting whether or not the grain has dried to the maximum drying rate value, and when the grain has dried to the maximum drying rate in one pass, the feed valve is driven to discharge and replace the grain. It is possible to effectively dry grains at the maximum drying loss rate without causing quality deterioration by changing the drying loss rate. Furthermore, since the total drying time can be shortened, loss of power and thermal energy can be prevented, and noise generation can be minimized to prevent noise pollution. Furthermore, while stopping the feeding of grain in the grain flow section of the drying section, the moisture value of the grain is directly measured, and the grain is discharged when the moisture value of the grain decreases to a value minus the maximum drying loss rate value. Therefore, good quality of grain can be maintained without delay in control response.

(2) If the configuration is such that a preheating section is provided between the storage section and the drying section, the grains are preheated within the preheating section, so the preheated grains are effectively dried in the drying section.
Drying work can be accomplished more quickly.

In addition, if the structure is such that an upper feed valve is provided at the upper end of the drying section, dried grains and undried grains can be completely separated, and uniform and reliable grain drying can be easily achieved within the drying section. It is possible.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view of the grain dryer of the invention, FIG. 2 is a block diagram showing the control circuit, and FIG. 3 is a drying control device. This is a flowchart explaining the action. 4 and 5 show a second embodiment of the present invention, FIG. 4 is a longitudinal sectional view of a grain dryer, and FIG. 5 is a flowchart explaining the operation of the drying control device of the second embodiment. . FIG. 6 is a graph diagram showing a normal dry state and a dry state according to the present invention. In the figure, 2 is a grain dryer, 4 is a storage section, and 6 is a grain dryer.
8 is a drying section, 8 is a grain collecting section, 14 is a grain flow path, 16 is a moisture meter, 22 is a lower delivery valve, 26 is a lower circulation motor, and 64 is a microcomputer.

Claims (1)

[Scope of Claims] 1. A moisture meter is provided to measure the grain moisture value in the grain flow path of the drying section, and an initial grain moisture value measured at the beginning of grain flow into the grain flow path of the drying section is stored in advance. a drying rate setting step in which the calculation means calculates and determines the maximum drying rate value for one pass based on the drying rate data stored in the means; and continuing drying while stopping at least the driving of the grain delivery valve. At the same time, the initial grain moisture value measured after the initial flow of the grain into the grain flow path of the drying section and the initial grain moisture value are compared by a comparing means, and the grain is reduced to the maximum drying loss rate value of the one pass. a drying confirmation step of detecting whether or not the grain has dried; and a valve drive control in which the feeding valve is driven by a command from the comparing means at the time when it is detected that the grain has dried to the large drying loss rate value of the one pass. A drying control method for a grain dryer, characterized in that drying is carried out by sequentially repeating a discharging and replacing step of discharging and replacing grains in the drying section. 2. A moisture meter that measures the grain moisture value in the grain flow path of the drying section and outputs a detection signal, and a means for storing in advance the initial grain moisture value measured at the initial stage when the grain flows into the grain flow path of the drying section. a calculating means for calculating the maximum drying loss rate value for one pass based on the drying loss rate data stored in the drying section; Comparing means for detecting whether or not the grain has dried to the maximum drying loss rate value of the one pass by comparing a post-initial grain moisture value measured after the initial flow of the grain into the path with the initial grain moisture value; , driving the feeding valve for a predetermined period of time in response to a command from the comparison means at the time when it is detected that the grain has dried to the maximum drying loss rate value of the one pass, and discharging the grain in the drying section;
1. A drying control device for a grain dryer, comprising a valve drive control means for replacing.