JPH0370980A - Control of drying in grain drier - Google Patents

Abstract

PURPOSE:To stabilize a reducing rate by drying of grains and prevent the deterioration of the capacity of a dehumidifying device by a method wherein the amount of sucked atmosphere and the amount of feedback discharging air are controlled to dry the grains so that the temperature of grains as well as the humidity of mixed drying air during drying become same as the preset values. CONSTITUTION:The mixed drying air of dehumidifying air from a dehumidifying device 2 and atmosphere from an atmosphere suction port 3 crosses and ventilates a drying chamber 1 and is sucked by an air discharging machine 5 to discharge it whereby grains are dried during flowing down from a reserving chamber 16 through the drying chamber 1. Thereafter, the grains are transferred and supplied to the upper part of the drying chamber 1 by a grain elevator 20, then, are diffused and fed back evenly into the reserving chamber 16 by a diffusing disk 19 whereby the grains are circulated and dried. When a moisture sensor 26 detects the moisture of the grains, which is same as an objective finishing moisture, a drier 7 is stopped automatically by the automatic control of the drying controller of an operating device 9. During this drying operation, the temperature of the grains is detected by a grain temperature sensor 25 and the humidity of the mixed drying air is detected by a humidity sensor 42 while the amount of atmosphere, sucked through the atmosphere suction port 3, and the amount of one part of the discharging air of the air discharging machine 5, fed back from a feedback device 6 to the dehumidifying device 2 through a circulating air port 29, are controlled so that both of the detected values become same as the set and stored values to dry the grains.

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, grains were repeatedly circulated through a drying chamber and flowed down, while the drying chamber was fed with a mixture of dehumidified air generated from a dehumidifying device and a certain amount of outside air sucked in from an outside air inlet. By passing the drying air through it, it is installed so that it is exposed to this mixed drying air and dried, and a certain amount of this exhaust air is sucked and exhausted from the drying chamber through the exhaust chamber and outside the machine by the exhaust fan. This was a drying control method in which the grains were dried by reducing the moisture to the dehumidifier using a reducing device.

Problems to be Solved by the Invention While the grains are repeatedly circulated through the drying chamber and flowed down,
By passing a mixed drying air, which is a mixture of dehumidified air generated from the dehumidifier and a certain amount of outside air taken in from the outside air intake, into this drying chamber.

This mixture is exposed to dry air and dried.

Also, during this drying work, a part of the exhaust air that is sucked out of the machine from the drying room using a light exhaust fan is returned to the dehumidifying device by a reducing device. The grains are dried by converting it into dehumidified air, but since the amount of return of this exhaust air is a certain amount, and the amount of outside air being taken in is a certain amount,
If the reducing exhaust air has high humidity, or if the outside air has low temperature and high humidity, the temperature of the grains during drying will not rise properly, and the drying loss rate of the grains will become unstable. When a large amount of high-humidity exhaust air is returned, the performance of the dehumidifier may be reduced.

Means for Solving the Problems This invention circulates and transfers grains to a drying chamber 1 while ventilating mixed drying air that is a mixture of dehumidified air from a dehumidifier 2 and outside air taken in from an outside air intake port 3. At the same time, an exhaust air 411 is provided from this drying chamber i through an exhaust chamber 4.
! Part of this exhaust air that is sucked out to the outside of the machine in step 5 is transferred to the dehumidifier!
! In a grain dryer equipped with a reducing device 6 for reducing the temperature to 2, the amount of outside air taken in and the amount of exhaust air to be returned are controlled so that the temperature of the grains during drying and the humidity of the mixed drying air become preset values. The drying control method is characterized by drying.

Effects of the Invention While the grains are repeatedly circulated through the drying chamber 1 and flowing down, a mixed drying air is generated into the drying chamber 1, which is a mixture of the dehumidified air generated from the dehumidifier N2 and the outside air taken in from the outside air intake port 3. is exposed to this mixed drying air and dried.

During this drying work, part of the exhaust air that is sucked and exhausted from the drying chamber 1 through the exhaust chamber 4 and outside the machine by the exhaust fan 5 is returned to the dehumidifying device 2 by the reducing device 6. The dehumidifier 2 converts it into dehumidified air to dry the grains, but the grain temperature during drying and the mixed drying air humidity are set to preset values, e.g.
Grain temperature is 16-18℃, mixed dry air humidity 50%-7
The grains are dried by controlling the amount of outside air to be taken in and the amount of exhaust air to be returned so that the drying rate is 5%.

Effects of the Invention According to the present invention, both the intake air volume and the exhaust air volume for reduction are controlled so that both the grain temperature during drying and the mixed drying air humidity become preset values. By keeping the grain temperature during drying at a constant temperature and also keeping the mixed drying air humidity within a constant humidity range, the drying loss rate of the grains is stabilized, and the high humidity exhaust air is A large amount is no longer reduced, and the performance of the dehumidifier 2 is thereby stabilized.

Embodiment In the example shown in FIG. 1, the mechanism 8 of the grain drying I17 has a rectangular shape long in the front and back direction, and is composed of front and rear wall plates and left and right wall plates,
The front wall board is provided with an operating device 9 for starting and stopping the dryer 7 and the dehumidifier 12 provided at the front of the dryer 7. Exhaust fan motor lO and valve motor 1 that rotationally drive the exhaust fan 5
．． This is a configuration with a 1st class.

In the center of the lower part of the mechanism 8, there is provided a grain collection gutter 12 which is equipped with a transfer spiral in the front and back direction, and above the grain collection gutter 12, a drying chamber L is arranged between ventilation mesh plates. The lower part of each drying chamber 1 is equipped with a feeding valve 13 for feeding and flowing grains, and a ventilation chamber 14 is formed between the inner sides of each drying chamber 1, and this ventilation chamber 14 and the dehumidifying device 2 A ventilation chamber 4 is formed on the outside of each drying chamber l, and each ventilation chamber 4
and the exhaust air Ja5 are configured to communicate with each other, and the valve motor 11 is configured to rotationally drive the delivery valve 13 via the deceleration mechanism 15.

A storage chamber 16 is formed above each drying chamber 1 and communicated with the storage chamber 16,
A transfer gutter 18 equipped with a ceiling plate L7 and a transfer spiral is provided above 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 on the lower side of the storage chamber 16 to uniformly diffuse and return grains into the storage chamber 16.

Grain raising @ 20 is provided in the front part of the front wall plate, and inside thereof, a packet conveyor 21 belt is stretched between the upper and lower boars, and between the upper end and the starting end of the transfer gutter 18 is a discharging cylinder 22. A supply gutter 23 is provided between the lower end and the terminal end of the grain collecting gutter 12 to communicate with each other.
A grain raising machine motor 24 is provided on the upper part of the grain raising machine 24, and the grain raising machine motor 24 is configured to rotationally drive the belt of the packet conveyor 21, the transfer spiral in the transfer gutter 18, the diffusion 5119, etc., and the feeder 23 A grain temperature sensor 25 is installed inside the feeder 23 to detect the temperature of the grains immediately after drying as they pass through the feeder 23, and a moisture sensor 2 is installed in the center vertically.
6 is provided, and is configured to receive grains that fall while being conveyed to the upper part by the packet conveyor 21, crush the grains under pressure, and at the same time detect the moisture content of the crushed grains. Each part of the moisture sensor 26 includes: It is configured to be rotated by a moisture motor 27 provided inside.

The dehumidifying device 2 has a box shape, and an air purifying bag M28 for purifying intake air is provided on the front side of the box, and a circulation air vent 29 and an outside air vent 3o for directly sucking outside air are provided on the front wall plate of the air purifying device 28. , and a purification filter 58 is provided inside, and the circulating air port 29 and the exhaust fan 5 are connected to return the exhaust air to the circulating air port 29 and discharge it to the outside of the machine 31. The configuration includes a reduction device 6 that performs switching,
This reducing device 6 is provided with a switching valve 32 that switches a part of the exhaust air between the circulating air port 29 side and the outside 31 side. It has a flexible configuration.

An outside air inlet 3 for sucking outside air is provided on the ceiling wall plate of the box of the dehumidifier 2, and an on-off valve 3 is installed in the outside air inlet 3.
4, this on-off valve 34 can be opened and closed by forward and reverse rotation of an on-off valve motor 35, and the circulating air a2 is provided inside.
The refrigerant is circulated from high temperature gas to high temperature high pressure liquid, low temperature low pressure liquid, and low temperature low pressure gas in order to convert the exhaust air returned from 9 and the outside air taken in from the outside air outlet 30 into high temperature and low humidity wind. While converting compressor 36, this compression 41i1
36, a condenser 38, an expansion valve 39, and an evaporator 40 are provided.The dehumidified air converted in this dehumidifier #1i2 and the outside air are installed on the rear side of this dehumidifier 2. This dehumidifier is equipped with a dehumidifier fan 43 that mixes outside air taken in through the suction port 3 to form mixed dry air and sends it to the ventilation chamber 14, and a humidity sensor 42 that detects the humidity of this mixed dry air. The fan 43 is the dehumidifying motor 41
This mixed drying air passes across the drying chamber 1 from the ventilation chamber 14 to dry the grains.

The operation device W9 has a box shape, and the surface plate of the box has a start switch 44 for starting and stopping the drying device 4117 and the dehumidifying device 2 for each drying and discharging operation, and a stop switch for stopping the operation. 45, each temperature setting machine 46 that controls the temperature of the dehumidified air generated from the dehumidifier 2, a moisture setting machine 47 that sets the finishing target moisture content of grains according to the operating position
．． The configuration includes a display window 49 and a monitor display that alternately display the detected temperature detected by the hot air temperature sensor 48, the grain moisture detected by the moisture sensor 26, the remaining drying time, etc., and a drying control device inside. 50 and temperature control device 51
Each of the setting knobs 46, 46, and 47 is of a rotary switch type, and a predetermined numerical value is set depending on the operating position.

The temperature control device 51 converts the detected values detected by the grain temperature sensor 25, the humidity sensor 42, and the temperature sensor 48 into A-
An A-D converter 52 that performs D conversion, an input circuit 53 to which the converted value converted by the A-D converter 52 is input, an input circuit 54 to which the operation of each temperature setting cancellation 46 is input. A CPU 55 that performs arithmetic and logical operations, comparison operations, etc. on various input values input from these input circuits 53 and 54;
This configuration includes an output circuit 56 that receives various commands from U55 and outputs them.

The drying control device 50 includes an AD converter that converts the detection value detected by the moisture sensor 26 into AD, an input circuit into which the converted value converted by this AD converter is input, and each of the switches 44. .45 and an input circuit into which the moisture setting adjustment 47 operations are input; the CPU which performs arithmetic and logical operations, comparison operations, etc. on various input values input from these input circuits;
55, the configuration includes an output circuit 56 that receives various commands from the CPU 55 and outputs them.

The drying control by the drying control device 50 is performed as described below. The grain moisture detected by the moisture sensor 26 is input to the CPU 55, and the CPU 55 operates the input value and the moisture setting switch 47. When the moisture sensor 26 detects the same grain moisture as the finishing target moisture, the drying control device 1
50 to automatically stop the dryer 7 and stop drying the grains.

Temperature control and air volume control by the temperature control device 51 are performed as described below. At the start of drying, control is performed to the CPU 55 according to the operating position of each temperature setting knob 46 depending on the grain size and the amount of filling. The set dehumidifying air temperature is compared with the detected temperature which is input to the CPU 55 when the temperature sensor 48 detects the temperature inside the blowing chamber 14, and if there is a difference, the set dehumidifying air temperature is set. The temperature control device 51 controls the amount of outside air taken in so that the temperature is the same as the wind temperature, and the grain temperature detected by the grain temperature sensor 25 is input to the CPU 55, and the grain temperature is input to the CPU 55. The mixed dry air humidity detected by the humidity sensor 42 is
This input detected grain temperature is compared with a set grain temperature of 16 to 18°C, for example, which is set and stored in the CPtJ55. The detected mixed dry air humidity and the set mixed dry air humidity (A) set and stored in the CPU 55, for example, 50
% and 75% of (B) are compared, and the switching valve motor 33 and the on-off valve motor 35 are controlled so that they are the same even if they are different. .

When the detected grain temperature is lower than the set grain temperature of 16 to 18°C, the opening/closing valve 34 of the outside air intake port 3 rotates in the forward direction for a predetermined period of time set and memorized by the CPU 55 of the opening/closing valve motor 35. The drive is controlled so that the distance between the outside air intake port 3 and the on-off valve 34 is narrowed by a predetermined width,
The outside air sucked in from this outside air intake port 3 is controlled to be reduced by a predetermined amount.Contrary to the above, when the detected grain temperature is higher than the set grain temperature of 16 to 18°C, the opening/closing valve 34 is controlled to rotate by reverse rotation for a predetermined period of time set and stored in the CPU 55 of the on-off valve motor 35, and the space between the outside air intake port 3 and the on-off valve 34 is controlled to be widened by a predetermined width. It is a 4I control in which the outside air taken in from the suction port 3 is controlled to increase by a predetermined amount, and the set grain temperature is 16 to 1.
When the temperature is 8° C., the on-off valve 34 is not controlled to open or close, but is fixed at a predetermined standard position that has been set and stored.

When the detected mixed drying air humidity is higher than 75% of the set drying air humidity (B), the switching valve 32 of the reducing device 6
is rotationally controlled by forward rotation of the switching valve motor 33 for a predetermined period of time set and stored in the CPU 55, and the switching valve 32 is controlled to move by a predetermined amount in the direction (A), and the switching valve 32 is controlled to move by a predetermined amount in the direction (A). 30 is configured to be controlled to decrease by a predetermined amount.Contrary to the above, when the detected mixed drying air humidity is lower than 50% of the set drying air humidity (A), the reducing device 16 The switching valve 32 is rotationally controlled by reverse rotation of the switching valve motor 33 for a predetermined period of time set and stored in the CPU 55.
2 is controlled to move a predetermined amount in the (b) direction, and this reduction device 6
The amount of reduced exhaust air returned to the circulating air opening 3° is controlled to increase by a predetermined amount, and the detected mixed drying air humidity is between 75% of the set drying air humidity CB) and 50% of (A). At this time, the switching control of the switching valve 32 is not performed and the switching valve 32 is fixed at a predetermined standard position that has been set and stored.

As in the other embodiments shown in FIGS. 7 and 8, an outside air temperature sensor 57 for detecting outside air temperature is provided on the outside of the bottom plate of the operating device 9, and the outside air temperature detected by this outside air temperature sensor 57 is , when the outside air temperature is lower than the temperature set and stored in the CPU 55, for example, 25° C., the switching valve 32 of the reducing device 6 is rotationally driven by the forward rotation of the switching valve motor 33 for a predetermined period of time. The switching valve 32 is controlled to move by a predetermined amount in the (b) direction, and the amount of reduced exhaust air returned from the reducing device 6 to the circulation air port 30 is controlled to increase by a predetermined amount. When the detected outside air temperature is higher than the set memory outside air temperature of 25°C, the switching valve 3
This configuration is such that the switching control of No. 2 is not performed, but is fixed at a predetermined standard position that has been set and stored.

Further, as in the other embodiment shown in FIG. 9, when the detected mixed dry air humidity is higher than 50% of the set dry air humidity (A), the on-off valve 34 of the outside air intake port 3 is operated by the on-off valve motor 3.
The rotation drive is controlled by forward rotation for a predetermined period of time set and stored in the CPU 55 of No. At the same time, the amount of outside air taken in is controlled to decrease by a predetermined amount, and at the same time, the rotation of the exhaust fan motor 10 that rotationally drives the exhaust fan 5 is controlled to decrease by a predetermined rotation that is set and stored in the CPU 55. The air volume sucked and discharged may be controlled to be reduced by a predetermined amount at
When the humidity is lower than 0%, the on-off valve 34 of the outside air inlet 3 is rotationally controlled by reverse rotation of the on-off valve motor 35 for a predetermined period of time set and stored in the CPU 55, and the opening/closing valve 34, and the amount of outside air taken in from the outside air intake port 3 is controlled to increase by a predetermined amount, and at the same time, the exhaust fan motor that rotationally drives the exhaust fan 5 10 rotations may be controlled to increase by a predetermined rotation set and stored in the CPU 55, and the amount of air sucked and discharged by the exhaust fan 5 may be controlled to increase by a predetermined amount.

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

Each part of the grain dryer 7, the moisture sensor 26, the dehumidifier 2, etc. is activated by operating each setting switch 46, 46, 47 of the operating device 9 to a predetermined position and operating the start switch 44 that starts drying work. starts, dehumidifying air is generated from the dehumidifying device 2, and mixed drying air, which is a mixture of this dehumidifying air and outside air taken in from the outside air intake port 3, crosses the drying room 1 from the ventilation chamber 14 and is exhausted. The grains stored in the storage chamber 16 of this dryer 7 are sucked and discharged by the exhaust air a5 through the wind chamber 4, and the grains are absorbed by this drying wind while flowing from the storage chamber 16 through the drying chamber i. The grains are exposed to water and dried, are fed to the lower part by the feed valve 13 and flowed down, are transferred from the collection gutter 12 to the feed gutter 23 into the grain raising machine 20 by the lower transfer spiral, and are fed to the upper part by the packet conveyor 21. It is conveyed to the storage chamber 16 through the dispensing tube 22 and supplied into the transfer gutter 18. From the transfer gutter 18, it is spread and supplied onto the plate 19 by the upper transfer spiral, and the diffusion plate 19 evenly distributes the liquid into the storage chamber 16. When the moisture sensor 26 detects the same grain moisture as the finishing target moisture set by operating the moisture setting/removal 47, the drying @control device 50 of the operating device 9 automatically Drying of the grains is stopped by controlling and automatically stopping the drying I17.

During this drying work, the grain temperature during drying is measured by the grain temperature sensor 25.
The mixed drying air humidity is detected by the humidity sensor 42, and the outside air air volume taken in from the outside air intake port 3 is adjusted so that the detected grain temperature and the detected mixed drying air humidity are the same as the set stored values. A portion of the exhaust air sucked and exhausted by the exhaust air a5 is returned from the reducing device IS to the dehumidifying device 2 via the circulation air port 29.The amount of the exhaust air returned is controlled and the grains are dried. .

[Brief explanation of drawings]

The drawings show an 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 a grain dryer that can be partially cut away, and Fig. 4 is a block diagram of the grain dryer. A-A in Figure 3
A sectional view, FIG. 5 is a rear view of a portion of the grain dryer, FIG. 6 is a partially cutaway front view of a portion of the grain dryer, FIGS. 7 and 8.
9 are views showing other embodiments, FIG. 7 is a flowchart, FIG. 8 is a partially cutaway front view of a part of the grain dryer, and FIG. 9 is a flowchart. Explanation of symbols 1 Drying chamber 3 Outside air inlet 5 Exhaust fan 2 Dehumidifier 4 Exhaust chamber 6 Reduction device

Claims (1)

[Claims] The drying chamber 1 is provided to circulate and transfer grains to the drying chamber 1 while blowing mixed drying air, which is a mixture of the dehumidified air from the dehumidifier 2 and the outside air taken in from the outside air intake port 3, for drying. In a grain dryer equipped with a reducing device 6 that returns a part of this exhaust air, which is sucked and exhausted to the outside of the machine by an exhaust fan 5 through an exhaust chamber 4, to the dehumidifying device 2, the grain temperature during drying is A drying control method that performs drying by controlling the amount of outside air taken in and the amount of exhausted air that is returned so that the humidity of the mixed drying air and the humidity of the drying air reach preset values.