JPH03113281A - Dry control system for grain dryer - Google Patents

Abstract

PURPOSE:To save drying energy and stabilize grain drying by detecting absolute humidity of dehumidified air before and after ventilating a dryer chamber, computing the difference between the humidity of the air, and drying the air under the control of an air capacity to be sucked and exhausted with an exhauster in order to maintain the compute differential humidity at a fixed value. CONSTITUTION:During drying operation a dehumidification humidity sensor 14 detects the absolute humidity of dehumidified air generated from a dehumidification device 2 prior to the passage through a drying chamber 1 while an exhausted air humidity sensor detects 15 in an exhaust chamber detects the absolute humidity of exhausted air which has passed the drying chamber 1. The difference between the thus detected absolute humidity is computed and the air capacity of open air to be sucked and exhausted with an exhauster 4 is sucked from an intake port 27 and converted into dehumidified air under the control to fix the differential humidity, thereby drying grains. Then, the computed differential humidity is compared with the predetermined differential humidity set and stored based on the classification of grain moisture content. When the difference is detected, the air capacity of open air is controlled so that it may be same as the predetermined differential humidity.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a drying control method for a grain dryer.

Conventional technology In the past, while the grains were fed into the drying chamber and allowed to flow down, dehumidified air from a dehumidifier was passed through the drying chamber, passed through the ventilation chamber, and then sucked and exhausted outside the machine by an exhaust fan. This was a drying control method in which the grains flowing down were exposed to this dehumidified air and dried.

Problems to be Solved by the Invention While the grain is repeatedly circulated through the drying chamber of the grain dryer and flowing down, the dehumidified air generated from the dehumidifier passes through this drying chamber, passes through the exhaust chamber, and is discharged by the exhaust fan. The grains flowing down the drying chamber are exposed to the dehumidifying air and dried by suction and exhaust air.This dehumidifying and drying process takes a long time to dry, but this is due to the This is because the grain temperature is kept low, which slows down the moisture transfer in the grains, and even if you increase the amount of dehumidifying air under these conditions, the drying rate of the grains will decrease. If the dehumidifying air does not improve and the grain moisture reaches a low moisture range, reducing the air volume of the dehumidifying air may reduce the drying rate and prevent drying from proceeding. The aim is to achieve energy-saving drying and stabilize grain drying.

Means for Solving the Problems Regarding the Invention of Claim 1 The present invention provides a system in which grains are fed into a drying chamber 1 and flowed down, while dehumidifying air from a dehumidifying device 2 is ventilated into the drying chamber 1 and exhausted through an exhaust chamber 3. In a grain dryer that sucks and exhausts air outside the machine using a fan 4 to dry the grain, the absolute humidity of both the dehumidifying air before ventilation and the exhaust air after ventilation in the drying chamber 1 is detected to calculate the humidity difference. The drying control method is characterized in that the air volume of the dehumidifying air sucked and discharged by the Makoto fan 4 is controlled in order to maintain the calculated humidity difference at a constant value.

Effect of the Invention While the grain is repeatedly circulated in the drying chamber 1 of the grain dryer and flowing down, the dehumidified air generated from the dehumidifier 2 passes through the drying chamber 1, passes through the exhaust chamber 3, and is sent to the exhaust fan. 4, the grains flowing down in the drying chamber 1 are
It is exposed to this dehumidified air and dried.

During this dehumidifying and drying work, the absolute humidity of the dehumidified air before it passes through the drying chamber 1 is detected, and the absolute humidity of the exhausted air after it passes through the drying chamber 1 is also detected. The detected absolute humidity between the two is compared to calculate the humidity difference, and the volume of dehumidified air sucked and exhausted by the exhaust fan 4 is controlled so that the calculated humidity difference is always a constant value. The grains are then dried.

Effects of the Invention According to this invention, the absolute humidity of the dehumidified air before passing through the drying chamber 1 and the absolute humidity of the exhaust air after passing through are detected, the humidity difference is calculated from both, and the calculated humidity difference The volume of dehumidified air sucked and discharged by the exhaust fan 4 is controlled so that the amount of water removed from the grains is maintained at a constant value. In addition, when the grain moisture reaches a low moisture range and becomes difficult to remove, the air flow is controlled to decrease, which eliminates wasted energy consumption and saves energy. Drying has been stabilized.

Means for Solving the Problems Regarding the Invention of Claim 2 The present invention provides a system in which dehumidified air from a dehumidifying device 2 is ventilated into the drying chamber 1 and exhausted through the exhaust chamber 3 while the grains are fed into the drying chamber 1 and flowed down. In a grain dryer that sucks and exhausts air outside the machine using a fan 4 to dry the grain, the absolute humidity of both the dehumidifying air before ventilation and the exhaust air after ventilation in the drying chamber 1 is detected to calculate the humidity difference. Drying is performed by controlling the volume of the dehumidifying air sucked and discharged by the exhaust fan 4 so that this calculated humidity difference is the same as a preset humidity difference that has been set and stored in advance based on the grain moisture content. The drying control method is configured as follows.

Effect of the Invention While the grain is repeatedly circulated through the drying chamber 1 of the grain dryer and flowing down, the dehumidified air generated from the dehumidifier 2 passes through the drying chamber 1, passes through the exhaust chamber 3, and is sent to the exhaust fan. 4, the grains flowing down in the drying chamber 1 are
It is exposed to this dehumidified air and dried.

During this dehumidifying and drying work, the absolute humidity of the dehumidified air before it passes through the drying chamber 1 is detected, and the absolute humidity of the exhausted air after it passes through the drying chamber 1 is detected. The detected absolute humidity of the two is compared to calculate the humidity difference, and this calculated humidity difference is compared with the humidity difference set and stored based on the grain moisture. If there is a difference, the set humidity difference is calculated. The grains are dried because the volume of the dehumidified air sucked and exhausted by the blower 4 is not controlled so that the drying temperature is the same.

Effects of the Invention According to this invention, the absolute humidity of the dehumidified air before passing through the drying chamber 1 and the absolute humidity of the exhaust air after passing through are detected, the humidity difference is calculated from both, and the calculated humidity difference The set humidity difference set and stored according to the grain moisture is compared, and the volume of dehumidified air sucked and discharged by the exhaust fan 4 is controlled so that it becomes the same as the set humidity difference. By controlling the amount of water removed to a constant value, when the grain moisture reaches a low moisture range and the amount of water removed decreases, reducing the air volume will further reduce the amount of water removed and drying will occur. Although the process slowed, grain drying was stabilized by controlling the air volume so that the amount of water removed remained constant.

Embodiment When the grain dryer 5 is rotated, the mechanism 6 of the grain dryer 5 has a rectangular shape that is long in the front and back direction and is made up of front and rear wall plates and left and right wall plates, and the dehumidifier 2 and the dryer 5 are installed on this front wall plate. An operating device 7 for starting and stopping the dehumidifying device 2 is provided,
The rear wall plate is provided with an exhaust fan 4, a variable speed exhaust fan motor 8 for rotating and driving the exhaust fan 4 at variable speeds, a valve motor 9 that rotates intermittently, and the like.

At the center of the lower part of the mechanism 6, there is provided a grain collection @10 in which a transfer spiral is rotatably supported in the front and back direction, and this grain collection gutter 1
0 upper side, drying chambers 1 formed between ventilation mesh plates are arranged in parallel and communicated with each other, and at the bottom of each drying chamber 1, a feeding valve 11 for feeding and flowing grains is rotatably supported. 1, a ventilation chamber 12 is formed between the inner sides thereof and communicated with the dehumidification device 2,
A ventilation chamber 3 is formed outside each drying chamber 1 and communicated with the ventilation fan 4, and the valve motor 9 is connected to the speed change mechanism 1.
A dehumidifying humidity sensor 14 is installed in the ventilation chamber 12 to detect the absolute humidity of the dehumidified air blown into the ventilation chamber 12 from the dehumidifying device 2. In addition, an exhaust air humidity sensor 15 is provided in the air exhaust chamber 3 to detect the absolute humidity of the exhaust air that is discharged after the dehumidified air passes through the drying chamber 1.

A storage chamber 16 is formed above each drying chamber 1 and communicated with the storage chamber 16,
A transfer gutter 18 in which a ceiling plate 17 and a transfer spiral are rotatably supported is provided on the upper side of the storage chamber 16, and a supply port for supplying transferred grains into the storage chamber 16 is provided in the center of the transfer gutter 18. A diffusion plate 19 is provided below the supply port to uniformly diffuse and return the grains into the storage chamber 16.

The grain raising machine 20 is installed in the front part of the front wall plate, and inside thereof, a packet conveyor 21 belt is stretched between upper and lower pulleys, and a discharging cylinder 22 is provided between the upper end and the starting end of the transfer gutter 18. A supply gutter 23 is provided between the lower end and the terminal end of the grain collection gutter 10 to communicate with each other.

The grain raising machine motor 24 installed on the upper part of the grain raising machine 20 moves the packet conveyor 21 belt, the transfer spiral in the transfer gutter 18, the spreading plate 19, and the packet conveyor 21 belt into the grain collection gutter 10. This configuration rotates the transfer spiral and the like.

A moisture sensor 25 installed approximately in the center in the vertical direction receives grains falling while being conveyed to the upper part of the packet conveyor 21, crushes the grains under pressure, and at the same time detects the moisture content of the crushed grains. Each part of the moisture sensor 25 can be controlled by transmitting an electrical measurement signal from the operating device 7.
The moisture motor 26 provided inside rotates, and is rotationally driven by the rotation of this moisture motor 26.

The dehumidifying device 2 has a box shape, and the front wall plate of the box body is provided with an inlet 27 for sucking outside air, and the rear wall plate is provided with an inlet 27 for inhaling outside air. The structure is provided with an air outlet 28 for blowing air into the air blowing chamber 12, and a refrigerant is used to convert the outside air sucked into the dehumidifier 2 into dehumidified air at a slightly higher temperature than the outside air. A certain low-temperature, low-pressure gas is adiabatically compressed into high-temperature, high-pressure gas in the compressor 29, and when it passes through the condenser 30, it loses heat and changes into a high-temperature, high-pressure liquid.Then, the pressure is reduced to a low-temperature, low-pressure liquid in the expansion valve 31. The refrigerant then absorbs heat when passing through the evaporator 32 and changes into low-temperature, low-pressure gas, and by sequentially repeating this cycle, the outside air passing through the dehumidifier 2 is dehumidified.

The state of the outside air sucked into the dehumidifier 2 is such that it is cooled when passing through the evaporator 32, and moisture in the air condenses to form low-temperature, low-humidity air with reduced absolute humidity. The compressor 29 is configured to suck heat when passing through the air to obtain low dehumidified air having a temperature slightly higher than room temperature, and the compressor 29 is rotationally driven by a compressor motor 33.

The operating device 7 is box-shaped, and has a start switch 34 on the surface plate of the box for installing the dryer 5 and the dehumidifying device 2, and a start switch 34 for starting the drying and discharging operations, and a stop switch 34 for stopping the dryer 5 and the dehumidifying device 2. A switch 35, a moisture setting strainer 36 for setting the grain finishing target moisture depending on the operating position, and a display window 37 for alternately displaying detected grain moisture, detected drying temperature, remaining drying time, etc.
and a monitor display, etc., and an outside air temperature sensor 38 for detecting outside air humidity and an outside air humidity sensor 39 for sensing outside air humidity are installed on the outside of the bottom plate, and a drying control device 4o, a temperature control device 41, etc. are installed inside. It has a configuration with
The moisture setting switch 36 is a rotary switch type,
This configuration is such that a predetermined numerical value is set by an operating device.

The drying control device 40 converts the detected values detected by the dehumidifying humidity sensor 14, the exhaust air humidity sensor 15, the moisture sensor 25, the outside air temperature sensor 38, and the outside air temperature sensor 39 from AD to AD. A converter 42, an input circuit 43 to which the converted value converted by the A-D converter 42 is input, an input circuit 44 to which the operations of the switches 34, 35 and the moisture setting control 36 are input, and each of these Input circuit 43.44
The configuration includes a CPU 45 that performs arithmetic and logical operations, comparison operations, etc. on various input values input from the CPU 45, and an output circuit 46 that receives and outputs various commands issued from the CPU 45.

The temperature control device 41 detects the temperature of the dehumidified air generated from the dehumidifying device 2 using a temperature sensor 47, and converts the detected value to A-.
An A-D converter that performs D conversion, an input circuit into which the converted value converted by this A-to-D converter is input manually, and a C that performs arithmetic and logical operations, comparison operations, etc. on the input values input from this input circuit.
The configuration includes a PU 45 and an output circuit 46 that receives various commands from the CPU 45 and outputs them.

The drying control by the drying control device 40 is performed as follows. When the moisture setting knob 36 is operated, this operating position is input to the CPU 45, and the finishing target moisture of the grain is set by this input. The moisture sensor 2
The grain moisture detected by 5 is input to the CPU 45, and the input detected grain moisture and the set finishing target moisture are compared, and when the detected grain moisture becomes the same as the set finishing target moisture, this drying The dryer 5 is automatically controlled by a control device 40 to automatically stop the dryer 5.

The dehumidifying humidity sensor 14 detects the absolute humidity of the dehumidified air in the ventilation chamber 12 and inputs it to the CPU 45, and the exhaust air humidity sensor 15 detects the absolute humidity of the exhaust air in the ventilation chamber 3. When the humidity is inputted to the CPU 45, the CPU 45 calculates the difference in absolute humidity between the two inputs, and the calculated humidity difference and the set humidity difference of the constant value set and stored in the CPU 45. are compared, and if there is a difference, it will be the same as the humidity difference of the set constant value,
The rotation speed of the exhaust fan motor 8 is controlled, and the rotation speed of the exhaust fan 4 rotationally driven by the exhaust fan motor 8 is controlled,
The exhaust fan 4 is configured to increase or decrease the amount of outside air sucked in through the suction port 27, and the CPU 45 controls the calculated humidity difference and grain moisture side.
The set humidity difference set and stored is compared, and if there is a difference, the rotation speed of the exhaust fan 4 is controlled in the same way as above so that the humidity difference is the same as the set humidity difference, and this exhaust fan 4, the amount of outside air sucked in through the suction port 27 is controlled to increase or decrease.

The outside air temperature is detected by the outside air temperature sensor 38 and the C
When the outside air humidity is detected by the outside air temperature sensor 39 and inputted to the CPU 45, the moisture gradient of the grain is estimated from both of these input values and set to the CPU 45. The CPU 45 calculates the grain circulation speed to make it the same as the set moisture gradient, and calculates the grain circulation interval from the calculated circulation speed. and is the same as this calculated circulation interval.
The CPU 45 controls the rotation interval of the valve motor 9, and the rotation interval of each delivery valve 11 rotationally driven by the valve motor 9 is controlled, and the delivery valve 11 is driven to rotate intermittently, so that the grains are circulated intermittently. This is a controlled configuration that prevents grain damage and reduced drying rate.

The temperature control and humidity control by the temperature control device 41 are performed as follows, and the temperature and humidity are set to be the same as the temperature and humidity of the dehumidified air generated from the dehumidifying device 2, which are set and stored in the CPU 45. , the temperature is determined by the temperature sensor 4
If the humidity is detected by the dehumidifying humidity sensor 14 and there is a difference, the amount of outside air taken in is controlled so that the temperature becomes the same as the set temperature. In this configuration, the rotation speed of the compressor motor 33 that rotationally drives the compressor 29 is controlled so that

Note that FIG. 7 and a part of FIG. 1 are views showing another embodiment, and as shown in FIG. The structure is equipped with a grain temperature sensor 48 that detects the temperature of Each switching valve 49 is provided individually to switch the refrigerant to the (a) passage or (b) passage, and by switching the switching valve 49, the refrigerant is switched to pass through the (a) passage. is converted into dehumidified air, and the grains are dried with this dehumidified air.Also, when the refrigerant is changed to pass through the (b) passage, the outside air is converted into cooling air, and this cooling air is used to dry the grains. is cooled to reduce grain temperature.

The detected value detected by the grain temperature sensor 48 is A-D converted by the A-D converter 42, and this converted value is input to the input circuit 43 and further input to the CPU 45, This input grain temperature is compared with the grain temperature set and stored in this CPU 45, and when the detected grain temperature is higher than the set grain temperature, this CPU 45 controls each switching valve 49.
The switching operation may be performed and the refrigerant passes through the (b) passage, and the structure may be configured to cool the grains and to prevent a decrease in taste due to an increase in the grain temperature of the grains.

Hereinafter, the operation of the above embodiment will be explained.

Operate the moisture setting knob 36 of the operating device 7 to a predetermined position,
By operating the start switch 34 that starts drying, each part of the grain dryer 5, the dehumidifier 2 and the moisture sensor 25
etc. are started, dehumidified air is generated from this dehumidifying device 2, and this dehumidified air passes from the ventilation chamber 12 to the drying chamber 1, passes through the ventilation chamber 3, and is sucked and exhausted by the exhaust fan 4. room 16
The grains stored in the storage chamber 16 are exposed to the dehumidified air and dried while flowing down the drying chamber 1 from the storage chamber 16, and then are fed to the lower part by the feeding valve 11 and flowed down into the grain collection gutter 10. The grains are transferred from the grain through the supply gutter 23 into the grain raising machine 20 by a lower transfer spiral, are conveyed to the upper part by the packet conveyor 21, and are fed into the transfer gutter 18 via the dispensing cylinder 22, and this transfer gutter 18
From there, it is transferred and supplied onto a diffusion plate 19 by an upper transfer spiral, and uniformly diffused and supplied into the storage chamber 16 by this diffusion plate 19,
The moisture sensor 25 is circulated and dried and the moisture setting strainer 36
When the moisture content of the grains is the same as the target moisture content set by operating the dryer 5, the drying control device 40 of the erroneous operation device 7 automatically controls the dryer 5 to automatically stop the dryer 5.

During this drying work, the absolute humidity of the dehumidified air generated from the dehumidifying device 2 before passing through the drying chamber 1 is detected by the dehumidifying humidity sensor 14 in the ventilation chamber 12, and after passing through the drying chamber 1, The absolute humidity of the exhaust air of The grains are dried while controlling the volume of outside air that is sucked in from the suction port 27 and converted into dehumidified air by the exhaust fan 4, and is set based on the calculated humidity difference and the grain moisture side. The stored humidity difference is compared with the set humidity difference, and if there is a difference, the outside air is drawn in from the inlet 27 and converted into dehumidified air by the exhaust fan 4 so that the humidity becomes the same as the set humidity difference. The grains are dried by controlling the air volume.

The calculated moisture gradient and the stored moisture gradient are compared, and if they are different, the intermittent rotation interval of the delivery valve 11 is controlled so that the gradient becomes the same as the set moisture gradient, and the grains are dried.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a block diagram, Fig. 2 is a flowchart, Fig. 3 is an overall side view of the grain dryer, and Fig. 4 is an A in Fig. 3. -A sectional view, 5th
The figure is a rear view of a part of the grain dryer, Figure 6 is a partially cutaway front view of a part of the grain dryer, and Figure 7 is a view showing another embodiment. It is an overall side view of a grain dryer. In the figure, symbol l is a drying room, 2 is a dehumidifier, 3 is an exhaust room, and 4 is a drying room.
indicates an exhaust fan.

Claims (1)

[Claims] 1. A dehumidifying device 2 while feeding grains into a drying chamber 1 and letting them flow down.
In a grain dryer in which dehumidified air is ventilated into the drying chamber 1, passed through an exhaust chamber 3, and sucked and exhausted outside the machine by an exhaust fan 4 for drying, this dehumidified air before being ventilated in the drying chamber 1 and The absolute humidity between the exhaust air after ventilation and the exhaust air is detected, the humidity difference is calculated, and the air volume of the dehumidifying air sucked and discharged by the exhaust fan 4 is controlled to maintain the calculated humidity difference at a constant value. A drying control method characterized by: 2 The dehumidifier 2 feeds the grains into the drying chamber 1 while letting them flow down.
In a grain dryer in which dehumidified air is ventilated into the drying chamber 1, passed through an exhaust chamber 3, and sucked and exhausted outside the machine by an exhaust fan 4 for drying, this dehumidified air before being ventilated in the drying chamber 1 and The exhaust fan detects the absolute humidity between the air and the exhaust air after ventilation, calculates the humidity difference, and makes this calculated humidity difference the same as a set humidity difference that has been set and stored in advance based on grain moisture. A drying control method characterized in that drying is carried out by controlling the volume of the dehumidifying air sucked and discharged in step 4.