JPH0150456B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a milling machine that can automatically detect the finishing time of rice milling and finish the rice milling operation in a timely manner when rice milling is performed using a circulating rice milling machine. This invention relates to an operation control method.

[Technical background of the invention and its problems]

Generally, in a circulating rice mill, as rice milling progresses, the milling load on the milling operating section changes significantly.
Figure 6 shows the relationship between milling load and milling time when rice milling is carried out under normal conditions for a conventional circulating rice mill.At the beginning of rice milling, the load is small; As rice bran is produced during rice milling, the load gradually increases and reaches the highest value in the chart. As the rice milling progresses further, the load gradually decreases as the rice bran mixed in the pounded rice is removed, and the load reaches an equilibrium state with almost no fluctuations shortly before the polishing process ends. . At this time, the rice grains are already in the state of polished rice, so
The final finishing (mainly bran removal) is carried out by moving the resistor and reducing the pounding pressure to zero.

However, in normal rice milling work, the setting position of the resistor that adjusts the milling force is fixed at a certain fixed position based on experience, and the process described above occurs. It is difficult to accurately grasp the timing; if the motor stops too early, unpolished rice will be produced, and conversely, if the motor stops too late, broken rice or over-milled rice will result, resulting in poor milled rice quality. There was a risk that it would decline.

[Purpose of the invention]

This invention was developed in order to address the above-mentioned problem, and it is possible to mill rice at the most appropriate point in the milling level by promoting a period in which the load is stable in the latter half of milling based on the series of load fluctuation patterns described above. The purpose of this study is to establish a method for controlling the pumping operation that can be completed.

[Summary of the invention]

The stirring operation control method of the present invention which achieves the above object is equipped with a control mechanism for appropriately reversing and stopping the sub-motor that moves the resistor of the stirring section in accordance with load fluctuations of the main motor that drives the stirring roller. In the milling operation control of the circulating rice mill, (a) the load current of the main motor is detected, and rice is milled regardless of load fluctuations while comparing this detected current with a preset load current;

(b) As rice milling progresses, when it is electrically detected that the milling load is balanced with almost no load fluctuation, the sub-motor is reversed and the resistance is set to a position where the milling pressure is almost zero. Move your body.

(c) When the milling pressure becomes almost 0, stop the sub-motor and perform the final milling operation.

(d) After a predetermined period of time has elapsed, the main motor is stopped to complete rice polishing.

This method is characterized in that rice is polished by controlling the milling operation in the following order.

[Embodiments of the invention]

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the circulating rice milling machine 10 shown in FIGS. 2 and 3, reference numeral 1 is a hopper, 2 is a milling chamber,
3 is a milling roll, 4 is a rice bran removal screen, 5 is a reflux port, and 6 is a resistor. The milling roll 3 is rotated through a belt 7 by the power of the main motor M inside the machine, and the rice grains put into the hopper 1 are The rice is forcibly circulated along the path shown by the arrow by the rotation of the polishing roll 3, and the rice is polished by friction between the roll 3 and the rice grains and grain-by-grain friction between the rice grains.

In the case of this embodiment, the resistor 6 is connected to the sub motor S mounted outside the machine without manually adjusting it.
The support shaft 6a of the resistor 6 is screwed into a nut 9 that can move forward and backward with respect to the helical shaft 8 that rotates in both forward and reverse directions.
are connected, and when the helical shaft 8 rotates in the positive direction as the sub motor S is driven, the resistor 6
rotates downward about the support shaft 6a as shown by the solid line arrow, and moves in the direction of increasing the milling pressure during rice milling. Further, when the sub-motor S rotates in the opposite direction, the resistor 6 rotates upward as shown by a dotted arrow, and moves in a direction to lower the pumping pressure.

FIG. 1 is a block diagram showing the configuration of an electric circuit that controls the circulating rice mill 10, FIG. 4 is a flow chart showing its control operation, and FIG. 5 shows the milling pressure controlled by the method of the present invention. In the curve graph showing the change, when the switch 12 is pressed to drive the main motor M, the power line of the main motor M that drives the milling roll 3 is equipped with a current transformer 13. A proportional secondary current is detected by current transformer 13. Next, this detected current is converted into a voltage by a converter inside the amplifier 14 and amplified, and then inputted to the microcomputer 16 by the A/D converter 15, and this and the pre-input reference for load current setting are While comparing the voltage,
If the sub-motor S is driven in the forward or reverse direction through the relay 17 based on the voltage difference between the two, when the load R is smaller than the reference setting value, the sub-motor S will rotate in the forward direction to increase the pumping pressure, and the load R will be lower than the reference setting. When the value exceeds this value, the driving of the sub motor S is stopped, but in the case of this embodiment, the main motor is stopped while the resistor 6 is fixed at an appropriate position, regardless of the above-mentioned load fluctuation. M is driven to perform the initial and middle pumping operations as shown in Figure 5, and then, in order to detect the end time of the pumping operation, the load is input and compared, and the same load is applied continuously or intermittently. Starts continuous or intermittent counting to measure the number of inputs.

After the count starts, when the previous input load R ₁ and the current input load R ₂ continuously show the same measurement value, the count number 1 is added sequentially, and the number of continuous same load currents becomes X, or the number of intermittent same load currents. When the milling load reaches the value Y (usually both X and Y several times), that is, when the milling load has very little variation and is almost in equilibrium, the rice grains have been milled almost to the point of being polished. At this point, the sub motor S is rotated in the reverse direction. Subsequently, when the sub-motor S reaches its reverse rotation limit and the resistor 6 moves to the position of the load O, the drive of the sub-motor S is stopped through the relay 17, and then,
Finishing rice milling work (mainly bran removal) is carried out for a predetermined time using means such as timer control under the condition of milling pressure O, and finally the drive of the main motor M is stopped via the relay 18.

Although a microcomputer is used for the control operation in this embodiment, it is not necessarily necessary to perform the control operation using a computer, and the control operation may be performed using another digital control circuit or an analog control circuit.

〔Effect of the invention〕

As described above, if the method of the present invention is applied to the milling operation control of a circulation-type rice milling machine, it is possible to promote the period when the load is stable in the latter half of milling, and to complete rice milling at the most appropriate point in terms of the degree of milling. , it not only prevents the occurrence of unpolished rice or over-milled rice and obtains high-quality milled rice, but also shortens milling time, greatly improves work efficiency, and makes efficient use of motor power. It has many excellent effects such as.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an example of a control circuit used to carry out the method of the present invention, Fig. 2 is a longitudinal sectional view showing the structure of a circulating rice mill to be controlled, and Fig. 3 is an adjustment of the milling pressure. FIG. 4 is a flowchart showing the sequence of control operations according to the method of the present invention; FIG. 5 is a curve graph showing changes in pumping load during control operations; FIG.
The figure is a curve graph showing the relationship between milling load and milling time in conventional rice milling operations. 1...Hopper, 2...Refining room, 3...Refining roll,
4...Blank removal net, 5...Return port, 6...Resistor, 6a...Spindle, 7...Belt, 8...Spiral shaft, 9...Nut, 10
...Circulating rice mill, M...Main motor, S...Sub motor, 11...Power supply circuit, 12...Rice milling start switch, 13...Current transformer, 14...Amplifier, 15...A/
D converter, 16...Microcomputer, 1
7... Sub motor drive relay, 18... Main motor drive relay, R... Load, R ₁ ... Previous load,
R ₂ …Current load.

Claims (1)

[Scope of Claims] 1. Milling operation control of a circulation type rice milling machine equipped with a control mechanism that timely reverses and stops a sub-motor that moves a resistor in a milling section in accordance with load fluctuations of a main motor that drives milling rolls. (a) The load current of the main motor is detected, and the detected current is compared with a preset load current to perform rice milling regardless of load fluctuations. (b) As rice milling progresses, when it is electrically detected that the milling load is balanced with almost no load fluctuation, the sub-motor is reversed and the resistance is set to a position where the milling pressure is almost zero. Move your body. (c) When the milling pressure becomes almost 0, stop the sub-motor and perform the final milling operation. (d) After a predetermined period of time has elapsed, the main motor is stopped to complete rice polishing. A method for controlling the milling operation of a circulating rice mill, characterized by controlling the milling operation in the following order to perform rice milling.