JPH0534063A - Discharge valve controller for circulation type grain dryer - Google Patents

Abstract

PURPOSE:To prevent interruption of circulation work and discharge work for grain due to the overload condition of a motor for driving a grain elevator and stabilize the circulation rate of grain by controlling the working time of, or the number of rotations of, a motor for driving a discharge valve in accordance with the detected value of an electric current to the motor for driving the grain elevator. CONSTITUTION:A value of an electric current to a motor 20 for driving a grain elevator is detected by a current transformer 32, and the detected signal is inputted into a control circuit 33. More particularly, the detected signal is inputted into a CPU 37 through an amplifier 34, an A/D converter 35 and an input circuit 36, and is then processed by the CPU. When an integrated value of the detected electric current value reaches a preset value, a control signal is outputted from the CPU 37. More particularly, the control signal is outputted to a semiconductor relay 41 through an output circuit 39 and an amplifier 40, and is then deenergized to stop operation of a motor 28 for driving a discharge valve. On the other hand, when the detected electric current value shows a normal electric current value, the semiconductor relay 41 is excited by the CPU 37 to start operation of the motor 28 for driving the discharge valve.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention prevents the grain circulation work and the discharge work from being interrupted due to the overload of a grain elevator motor, and controls the discharge valve of a circulation type grain dryer for stabilizing the grain circulation amount. Regarding the device.

[0002]

2. Description of the Related Art A circulating grain dryer comprises a storing section, a drying section and a grain collecting section, and the grain collecting section communicates with the storing section via a grain lifting machine to form a circulating grain stroke. Then, after the grain put into the storage section is dried in the drying section, it is intermittently supplied to the grain collecting section by the discharge valve provided below the drying section, and is thrown from the grain collecting section by the grain lifting machine, It is circulated until a predetermined water content is reached.

[0003]

In the conventional circulation type grain dryer as described above, when the amount of grains discharged by the discharge valve exceeds the grain-lifting capacity of the grain-weighing machine, the motor for driving the grain-weighing machine is overloaded. In this state, the thermal relay and safety switch for protecting the motor are activated to stop the operation of the motor and prevent the motor from being burned. However, when the motor is overloaded and the operation of the motor is stopped, the drying operation is interrupted during the drying operation, and the discharging operation is interrupted during the ejection operation, which significantly reduces the work efficiency. was there.

The present invention solves the above-mentioned drawbacks of the conventional apparatus, prevents interruption of grain circulation work and discharge work due to overload of the grain elevator motor, and stabilizes the grain circulation amount. An object of the present invention is to provide a discharge valve control device for a circulating grain dryer.

[0005]

[Means for Solving the Problems] In a circulation type grain dryer having a storage section, a drying section, a grain collecting section and a grain lifting machine, which are formed in a circulating grain process, and a discharge valve is provided below the drying section, A drive motor for rotating the discharge valve, a current detector interposed in the power source of the motor for driving the grain elevator, and a current value detected by the current detector and an upper limit or a lower limit set current value are compared, A discharge valve control device for a circulating grain dryer, comprising: a control device that controls the operating time or the rotation speed of the discharge valve driving motor when the set current value is continuously detected for a predetermined time.

[0006]

The detection signal from the current detector interposed in the power source of the motor for driving the grain elevator is input to the control unit, and the control unit compares the detected current value with the upper limit or lower limit set current value and waits for a predetermined time. When the set current value is continuously detected, the operating time or the rotation speed of the discharge valve driving motor is controlled to adjust the discharge amount of grain by the discharge valve.

[0007]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram of the discharge valve control device, FIG. 2 is an enlarged view showing a drive unit of the circulating grain dryer, and FIG. 3 is a partial front sectional view of the circulating grain dryer.

Reference numeral 1 is a circulation type grain dryer, in which a tempering chamber 2 is provided at an upper portion and a ventilation drying unit 3 is provided at a lower portion, and a grain lifting machine 4 is erected on one side thereof to form a circulation grain drying process. To do. In the ventilation drying section 3, a drying chamber 5 and a hot air chamber 6 formed by a porous wall plate
And the discharge chamber 7 are arranged side by side, and the upper part of each drying chamber 5 communicates with the tempering chamber 2. The lower part of the drying chamber 5 is connected to the grain flow-down passage 8 and a discharge valve 9 is provided at its discharge port. 10 is a grain collecting gutter, and a lower carrier 11 is provided at the bottom of the gutter.
Is connected to the tempering chamber 2 via the grain elevator 4, the upper transporter 12, and the scattering plate 13.

In the conveyor case 14 of the grain elevator 4, a belt 16 having a large number of buckets 15 is attached to the upper and lower pulleys 1.
It is provided by winding between 7 and the opening 18 at the upper end of the fried machine 4 communicates with the upper carrier 12 via the downflow gutter 19 and 20 is a motor for driving the fried machine.

A guide plate 21 for collecting return grains from the bucket 15 is provided between the belts 16 and 16 of the grain elevator 4 in an inclined manner, and the guide plate 21 communicates with a moisture measuring device 23 via a supply cylinder 22. Then, the moisture measuring device 23 communicates with the lower opening (not shown) of the conveyor case 14 via the discharge gutter 24 and the return gutter 25.

Reference numeral 26 denotes a discharge valve driving device (see FIG. 2), which includes sprockets 27, 27 mounted on the shafts of the discharge valves 9, 9 and a sprocket 29 mounted on a discharge valve driving motor 28 and a tension sprocket 30. Wind the chain 31.

Next, the circuit of the discharge valve control device will be described with reference to FIG. A current transformer (CT) 32 that detects the current value of the motor 23 is interposed in the power source of the motor 20 for driving the grain elevator, and the current transformer 32 includes an amplifier 34 of a control circuit 33, an AD converter 35, and an input circuit 36. C that calculates various input values via
Contact PU37. The CPU 37 is connected to a storage device 38 including a RAM and a ROM, and the CPU 37 uses the output circuit 3
The exhaust valve drive motor 28 is communicated via the amplifier 9, the amplifier 40, and the semiconductor relay 41.

Next, the operation of the above configuration will be described. Grains (eg, paddy) supplied to a hopper (not shown) are lifted by the grain lifting machine 4, passed through the upper transporter 12, and scattered from the scattering plate 13 into the tempering chamber 2 evenly and accumulated. To be done. Next, when the fire heat generator (not shown) and the blower (not shown) are operated to rotate the discharge valve 9, the grain in the tempering chamber 2 flows down in the drying chamber 5. The grain flowing down in the drying chamber 5 is dried at a high temperature by the dry air flowing laterally from the hot air chamber 6 to the air exhaust chamber 7, and the dry air is discharged from the air exhaust chamber 7 to the outside of the machine by an exhaust fan (not shown). .. Grains that have been hot-air dried by the dry air flow down through the grain flow path 8 and are intermittently discharged by the discharge valve 9. The discharged grain flows down through the grain collecting trough 10 and is sent to the grain fried machine 12 by the lower carrier 11 and is put into the tempering chamber 2 again, and is circulated and dried until the moisture measuring device 23 detects a predetermined moisture. It

Grains to be pumped by the grain lifting machine 4 are shaken at the time of conveyance and discharged to the downflow gutter 19 so that the bucket 15
Spills between the two belts 16, 16. The spilled grain is collected by the guide plate 21, flows down from the guide plate 21 through the supply cylinder 22 and is supplied to the moisture measuring device 23, and the moisture of the grain is measured. The grain whose moisture has been measured is discharged from the moisture measuring device 23, flows down the discharge gutter 24, and returns to the return gutter 25.
Is supplied to the lower part of the conveyor case 14.

Next, the operation of the discharge valve control device will be described (see FIG. 1). The current value of the motor 20 for driving the grain elevator is detected by the current transformer 32, and the detection signal is amplified by the amplifier 34 and then AD-converted by the AD converter 35. The AD-converted conversion value is input to the CPU 37 via the input circuit 36, and arithmetic and comparison operations are performed in the CPU 37. When the integrated value of the detected current value reaches the set value by the calculation, CP
A signal is output from U37, and the output signal is the output circuit 3
9. The signal is sent to the semiconductor relay 41 via the amplifier 40, which demagnetizes the semiconductor relay 41 and stops the operation of the discharge valve driving motor 28. And the current transformer 32
When the detected current value becomes a normal current value, the semiconductor relay 41 is excited by the output signal from the CPU 37, and the operation of the discharge valve driving motor 28 is started.

Next, the control of the discharge valve control device will be described in detail. The discharge valve 9 of this embodiment is operated for a predetermined time (for example, 30 seconds) to discharge the grain, and is stopped for a predetermined time to stop the discharge of the grain.

First, the current value (normal set current value) during normal operation of the motor 20 for driving the grain elevator is set to 100. This set value can be arbitrarily set according to the amount of grain swelling. For example, when the rated current of the motor 20 is 4A,
At full capacity, set current 3A is 100 and the amount of swelling is 50
It is possible to set the set current 2A at the time of 100% to 100 in multiple stages according to the amount of stake.

When a load condition occurs, for example, the ratio of the detected current value to the normal set current value of the motor 20 becomes 1
When it exceeds 20% (upper limit set current value), the coefficient value is decremented by 1 per second, and when it reaches 90 (100 -1 x 10 seconds), the operation of the discharge valve drive motor 28 is stopped (the above-mentioned (See the circuit diagram) to suspend the operation of the discharge valve 9. Next, the stopped state is continued until the load state is canceled and the normal set current value is restored. When the normal set current value is restored, the current operating time of the discharge valve 9 is multiplied by a predetermined coefficient (for example, 0.9). As a result, the subsequent operating time of the discharge valve 9 is reduced, the amount of grain discharged per hour is reduced, and the overload of the grain elevator driving motor 20 is prevented.

On the contrary, when the ratio of the detected current value to the normal set current value is lower than 90% (lower limit set current value), one coefficient value is added per second, and 110 (100+
1 × 10 seconds), the current operating time of the exhaust valve 9 is multiplied by a predetermined coefficient (eg 1.1), and the subsequent exhaust valve 9
To increase the operating time of grain and increase the hourly discharge of grain. The above control procedure is stored in the storage device 38 of the control circuit 33.

As described above, by detecting the current value of the motor 20 for driving the grain elevator, the operating time of the discharge valve 9 is controlled to adjust the amount of grain discharged, so that the thermal relay is caused by the overload of the motor 20. And the safety switch is activated,
Grain circulation and discharge operations are not interrupted. In addition, since it is possible to detect a change in the circulation amount of grain as a change in the current value of the motor 20 for driving the grain lifting machine, the actual circulation amount is different from the set circulation amount that is assumed according to the stake amount. When the number is large, the operating time of the discharge valve 9 can be reduced to reduce the circulation amount. Conversely, when the actual circulation amount is smaller than the set circulation amount, the operating time of the discharge valve 9 can be increased to increase the circulation amount, and the set circulation amount can always be maintained.

As another embodiment, the current value (normally set current value) of the grain-driving machine driving motor 20 during normal operation is set to 100, and the ratio of the detected current value to the normally set current value is 120%. In this case (upper limit set current value), for example, 120 is set. Then, when the detection value of 120 or more is continuously detected for 10 seconds, the discharge valve 9 is temporarily stopped, and when the normal set current value (set value 100) is restored, the current operating time of the discharge valve 9 is multiplied by, for example, a predetermined coefficient 0.9 to discharge. Reduce the amount. Conversely, when the ratio of the detected current to the normal set current value is 80% (lower limit set current value) is set to 80 and 80% or less is continuously detected for 120 seconds, the current discharge time of the discharge valve 9 has a predetermined coefficient of 1.2.
Multiply by to increase emissions. As described above, various control methods are conceivable.
It suffices to change the operating time or the rotation speed of the discharge valve driving motor 28 to change the discharge amount of the grain of the discharge valve 9 by comparing the detected current value and the normal set current value. Although the discharge amount of the discharge valve 9 in the present embodiment is adjusted by operating or stopping the operating time of the discharge valve driving motor 28, the rotation speed is controlled by using the variable rotation speed motor. Thus, the amount of grain discharged from the discharge valve 9 may be adjusted.

[0022]

According to the discharge valve control device of the circulating grain dryer of the present invention, the discharge amount of the grain from the discharge valve is adjusted by controlling the operating time or the rotation speed of the discharge valve driving motor. Therefore, the thermal relay, the safety switch, etc. do not operate due to the overload of the motor for driving the grain elevator, and the grain circulation work and the grain discharge work are not interrupted. Further, since the change in the circulation amount of grain can be detected as the change in the current value of the motor for driving the grain elevator, it is possible to always maintain the ideal set circulation amount that is assumed according to the amount of stake.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a discharge valve control device.

FIG. 2 is an enlarged view showing a drive unit of a circulation type grain dryer.

FIG. 3 is a partial front sectional view of a circulation type grain dryer.

[Explanation of symbols]

 1 Circulating Grain Dryer 2 Conditioning Room 3 Ventilation Drying Section 4 Grain Lifting Machine 5 Drying Room 6 Hot Air Room 7 Exhaust Chamber 8 Grain Downflow Path 9 Discharge Valve 10 Grain Gutter 11 Lower Conveyor 12 Upper Conveyor 13 Scattering Board 14 Conveyor case 15 Bucket 16 Belt 17 Pulley 18 Opening 19 Downflow gutter 20 Motor for driving grain elevator 21 Guide plate 22 Supply cylinder 23 Moisture measuring device 24 Discharge gutter 25 Return gutter 26 Discharge valve drive device 27 Sprocket 28 Discharge valve drive motor 29 Sprocket 30 Tension Sprocket 31 Chain 32 Current Transformer 33 Control Circuit 34 Amplifier 35 AD Converter 36 Input Circuit 37 CPU 38 Storage Device 39 Output Circuit 40 Amplifier 41 Semiconductor Relay

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazushige Masuda 2-30, Saijo Nishihonmachi, Higashihiroshima City, Hiroshima Prefecture Satake Works

Claims (1)

Claim: What is claimed is: 1. A circulation type grain dryer having a storage section, a drying section, a grain collecting section and a fried machine that form a circulation grain drying step, and a discharge valve is provided below the drying section. In, a drive motor for rotating the discharge valve, a current detector interposed in the power source of the motor for driving the grain elevator, and a current value detected by the current detector and an upper limit or a lower limit set current value are compared. Then, when the set current value is continuously detected for a predetermined time, the discharge valve control of the circulation type grain dryer comprises a control device for controlling the operating time or the rotation speed of the discharge valve driving motor. apparatus.