JPH0150457B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention automatically detects the finishing time of milling according to the degree of polishing and optimizes the rice milling operation when a circulating rice milling machine is used to mill rice. The present invention relates to a method for controlling the ejaculation operation that can be completed at an appropriate time.

[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 pressure is empirically fixed at a certain fixed position, and the process described above occurs. It is difficult to accurately determine the end time of the milling operation depending on the situation.If the motor is stopped too early, unpolished rice will be produced, and if the motor is stopped too late, broken rice or over-milled rice will be produced. There was a risk that the quality of the milled rice would deteriorate significantly over time.

[Purpose of the invention]

This invention was developed to deal with the above problem, and it is possible to select the most suitable time according to the type of rice to be milled by promoting the period when the load is stable in the latter half of milling based on the series of load fluctuation patterns mentioned above. The purpose of this study is to establish a control method for the milling operation that can complete the rice milling process.

[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) After that, the milling load that is smaller than the value set at the initial stage of milling multiplied by the predetermined rate α and larger than the value multiplied by the predetermined rate β maintains equilibrium with almost no fluctuation. When the state is electrically detected, the sub-motor is reversed and the resistor is moved to a position where the pumping pressure is approximately zero.

(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 the electric circuit that controls the circulating rice milling machine 10, FIG. 4 is a flowchart showing its control operation, and FIG. 5 shows the milling load 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.

In this case, the counting conditions are such that a pumping load that is smaller than the value set at the initial stage of pumping multiplied by a predetermined rate α and larger than the value multiplied by the predetermined rate β is input after the count starts, and input load
When R ₁ and the current input load R ₂ show the same measured value in succession, a count of 1 is added sequentially, and the number of continuous same load currents is X, or the number of intermittent same load currents is Y ( (usually several times for both Rotate backwards. At this time, the standard rate by which the set load is multiplied is 95% for α and 80% for β, but depending on the value of the set load, the rates for α and β may be further increased by 5 to 10%.

Subsequently, when the sub motor S reaches the reverse limit and the resistor 6 moves to the zero load position, the relay 17
The drive of the sub-motor S is stopped through the relay 18, and then the finishing rice milling operation (mainly bran removal) is performed for a predetermined period of time by means such as timer control in a state where the milling pressure is 0. Finally, the main motor M is
Stops driving.

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 it may be performed using other digital control circuits or analog control circuits.

〔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 select the most suitable method according to the type of rice to be milled. Since rice milling can be completed at the same time, it is possible to obtain high-quality milled rice with the desired degree of polishing while preventing the occurrence of unpolished rice, broken rice, and over-milled rice.It also reduces milling time and improves work efficiency. It has many excellent effects, such as greatly improving the performance of the motor and making efficient use of the motor's power.

[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) After that, the milling load that is smaller than the value set at the initial stage of milling multiplied by the predetermined rate α and larger than the value multiplied by the predetermined rate β maintains equilibrium with almost no fluctuation. When the state is electrically detected, the sub-motor is reversed and the resistor is moved to a position where the pumping pressure is approximately zero. (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 in that rice is polished by controlling the milling operation in the following order.