JPH0815563B2 - Control device of rice mill - Google Patents

Description

TECHNICAL FIELD The present invention relates to a rice milling machine for whitening brown rice and processing it into white rice.

2. Description of the Related Art In a rice polishing machine, as shown in FIG. 3, a feeding roll 2, a whitening roll 3 and a net 4 are arranged inside a whitening cylinder 1, and the feeding roll 2 and the whitening roll 3 are driven by a motor 5. The brown rice that has flowed from the hopper 6 into the white polishing cylinder 1 is pushed by the feeding roll 2 toward the rice polishing chamber 7 formed by the whitening roll 3 and the net 4. A resistance plate 10 is pressed against the white rice outlet 8 by a spring 9. When the internal pressure of the polishing chamber 7 rises, the resistance plate 10 resists the biasing force of the spring 9.
When 10 moves, the polished rice is discharged from the polished rice outlet 8. The bran generated by the whitening passes through the net 4 and is discharged from a bran outlet (not shown) different from the white rice outlet 8.

Conventionally, a meter relay 11 is provided in the power supply circuit of the motor 5, and when the current flowing in the motor 5 falls below a specified current value set in the meter relay, it is determined that the whitening has ended and the energization of the motor is ended. Circuit is configured.

Problems to be Solved by the Invention Since the end time of rice polishing is detected in this way, if the power supply voltage changes depending on the season or region, an error occurs in the detection of the end time of rice polishing. Therefore, a troublesome operation of correcting the set value of the meter relay 11 is required in the usage area.

Furthermore, when a rice polishing machine is used, the bran may be attached to various places and the load on the motor 5 may increase, and even though the polishing has been completed, the power supply to the motor 5 may not be completed. If there is a large amount of bran adhered, there is a problem that the load current value immediately after the motor 5 is operated is large and the overload relay operates to prevent operation.

It is an object of the present invention to provide a control device that can stably detect the end time of rice polishing without being affected by fluctuations in power supply voltage and fluctuations in load due to adhesion of rice bran.

Means for Solving the Problems The control device of the rice milling machine according to claim 1 is a rice milling machine for whitening brown rice that has been fed into a milling chamber by driving a whitening roll with a motor, and the brown rice is loaded into the milling chamber. When the load current value when the motor is operated in the non-heated state is I _O , and the load current value of the motor during the rice polishing operation is I _W when brown rice is put into the polishing chamber, the load current value difference (I It is characterized by the provision of a control unit that compares the threshold value calculated according to the size of ( _{W- IO} ) with the load current value from time to time to detect the end time of rice polishing.

The control device for a rice polishing machine according to claim 2, wherein a torque sensor is provided in a power transmission system from the motor to the whitening roll, and a detected torque value when the motor is operated in a state where brown rice is not introduced into the polishing chamber. Is T _O , and brown rice is put into the polishing chamber and the torque detection value during rice polishing operation is T _W , the threshold value calculated according to the magnitude of the detected torque value difference (T _W −T _O ) and the It is characterized in that a control unit for comparing the detected torque values to detect the rice polishing end time is provided.

According to the configuration of claim 1, the load current value I _{O in the} no-load state
And the load current value I _W during the rice milling process is calculated based on the difference current value, and the rice milling end time is calculated by comparing the calculated threshold value with the load current value I _{W from} time to time. judge.

According to the configuration of claim 2, the detected torque value T _{O in the} no-load state
And the detected torque value T _W during the rice milling process, a threshold for rice milling end time determination is calculated based on the difference torque value, and the calculated milling end time is compared with the detected torque value T _{W from} time to time to determine the rice milling end time. judge.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

A rice milling machine equipped with the control device of the present invention is configured as shown in FIG. Current detector in the power circuit of the motor M1
12 is provided, and the control unit 13 controls the operation of the motor M1 as follows based on the detected value. A screw feeder 14 is attached to the brown rice inlet to control the feeding of brown rice into the polishing chamber 7.

The control unit 13 is configured as in the flowchart shown in FIG. When the start instruction 15 is detected, the control unit 13 turns on the switch 16 at # 1 to start the operation of the motor M1. At this time, the motor M2 of the screw feeder 14 has not been operated yet, and brown rice has not been introduced into the polishing chamber 7.

In # 2, the detected current value of the current detector 12 in this unloaded state is stored as I _O , and in # 3, the switch 17 is turned on to operate the motor M2 of the screw feeder 14 to drive the grinding chamber 7
Brown rice is put in.

When the input of brown rice is started in # 3, the control unit 13 reads the current detection current value I _W of the current detector 12 after the stipulated time in # 4, and in # 5, the rice milling end time is as follows. The threshold value I _S used for the determination of is calculated and stored.

I _S = (I _W −I _O ) · α where α is a coefficient “0 <α <1”.

When the threshold I _S is determined, the control unit 13 reads the current detection current value I _W = I _WT of the current detector 12, and in # 7, compares I _WT read in # 6 with the threshold I _S to obtain “I _S > I _WT "is determined. # 6 and # 7 until the detected current value I _WT falls below the threshold value I _S
When the state of “I _S > I _WT ” is detected in # 7, the rice polishing end process is executed in # 8. Specifically, as the rice polishing processing, the switches 16 and 17 are turned off immediately or after a predetermined time.

It should be noted that the rice milling completion detection time can be changed by selecting the coefficient α.

In this way, the control unit 13 sets the threshold value I _{S at} each startup based on the no-load current value I _O immediately after the startup and the load current value I _W during the rice sourcing operation.
Therefore, rice milling operation can be performed even in a state where the adhesion of bran has progressed and the load has become heavy.

Further, for the same reason that the control unit 13 determines the threshold value I _S each time it is started, the rice milling end time can be accurately detected even if the power supply voltage changes depending on the season or region.

In the above embodiment, the detected current value of the current detector 12 is controlled by the control unit.
It was processed by 13 and operated, but this is equipped with a torque sensor 18 in the power transmission system from the motor M1 to the whitening roll 3 as shown by the phantom line in FIG. 1, and brown rice is not introduced into the polishing chamber The torque detection value when the motor M1 is operated in the state is T _O , and the torque detection value during the rice polishing operation is T _W
In such a case, the control unit 13 is configured to detect the rice polishing end time by comparing the threshold value calculated according to the magnitude of the detected torque value difference (T _W −T _O ) with the detected torque value at each time. Can expect the same effect. Specifically, the threshold value T _S used for determining the end time of rice polishing is determined by T _S = (T _W −T _O ) · α, and 0 <α <1 ”.

Advantageous Effects of Invention According to the configuration of each claim, the load current value or the detected torque value when the motor is operated in a state where brown rice is not input to the polishing chamber and the load during the rice polishing operation when brown rice is input. A control unit that compares the threshold value calculated according to the magnitude of the difference between the current value or the detected torque value with the load current value or the detected torque value at each time to detect the rice polishing end time is provided, so that it is automatically An appropriate threshold value can be determined, and even if the bran adheres or the power supply voltage changes depending on the season or region, the rice-polishing operation can be performed and the rice-finishing finish time can be accurately detected.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a control device for a rice polishing machine according to the present invention, FIG. 2 is a flow chart of the same device, and FIG. 3 is a block diagram of a conventional rice polishing machine. 2 ... Sending rolls, 3 ... Whitening rolls, 7 ... Lesser room, 12
… Current detector, 13… Control unit, 14… Screw feeder,
18 ... Torque sensor.

Claims (2)

[Claims] 1. In a rice milling machine for milling brown rice that has been fed into the milling chamber by driving a milling roll with a motor, the load current value when the motor is operated in a state where brown rice is not loaded in the milling chamber. the I _O, a load current value of the motor in the milled rice operation by introducing the brown rice pearling chamber when the I _W, the threshold calculated in accordance with the magnitude of the load current value difference (I _W -I _O) The control device for the rice milling machine is provided with a control unit that compares the load current value from time to time to detect the end time of rice polishing. 2. A rice milling machine for milling brown rice that has been introduced into the milling room by driving the milling roll with a motor, wherein a torque sensor is provided in the power transmission system from the motor to the milling roll, When the detected torque value when the motor is operated in a state where brown rice is not input is T _O and the detected torque value during operation of polishing rice with brown rice is T _W , the detected torque value difference ( (T _W -T _O ) A control device for a rice milling machine that includes a control unit that compares the threshold value calculated according to the magnitude of T _W -TO) with the detected torque value at each time to detect the rice polishing end time.