JPH0732883B2 - Control device of rice mill - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control device for a rice polishing machine, and more particularly to an improvement in stop control thereof.

[Conventional technology]

Generally, in a circulating rice mill, the time required for rice polishing is long for low-moisture brown rice and short for high-moisture brown rice. Therefore, it is necessary to appropriately set the rice polishing time according to the quality of rice such as water content and variety. However, it is difficult to properly set the rice-polishing time according to the quality of rice, and as a result, if the rice-polishing time is conventionally set to be short, the polishing will be insufficient and it will be necessary to re-polish the rice. When set to a long time, there was a problem that the whitening became excessive, and therefore the yield of the finished white rice decreased and the amount of broken rice in the white rice increased.

[Problems to be solved by the invention]

It is an object of the present invention to provide a control device for a rice polishing machine, which prevents insufficient or excessive whitening, the configuration of which is shown in FIG.

That is, a rice milling machine provided with a main motor for driving a rice milling screw for pumping rice into the pressure chamber and an auxiliary motor for moving a resistor for adjusting the whitening pressure in the pressure chamber is provided. In the control device of the rice milling machine that adjusts the polishing pressure by moving and fixing the operation of the resistor based on the load of the main motor during milling, the load of the main motor after fixing the operation of the resistor The whiteness degree detecting means for continuously detecting the change and calculating the temporal change amount accompanying the load change of the main motor from the detected load of the main motor and its detection interval, and the calculated temporal change amount. Provided is a control device for a rice polishing machine, which is provided with a whitening degree judging means for judging a whitening degree of the rice compared with a predetermined value associated with the rice to be pumped.

[Work]

According to the above configuration, the degree of whitening is detected indirectly or directly, and the rice polishing is stopped based on the degree of whitening.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an overall configuration diagram of a rice polishing machine according to the present invention. Second
In the figure, 1 is a rice polishing tank into which rice 2 is put, and a rice polishing screw 4 is provided in communication with a bottom portion 3 thereof. The screw 4 is driven by a main motor 5. Reference numeral 6 is a bran removal mesh, and 7 is a circulating shutter that opens and closes the communication passage of the bottom portion 3. Reference numeral 8 is a resistor for adjusting the pressure in the pressure chamber 9 at the outlet of the communication passage of the bottom portion 3, which is advanced or retracted by the auxiliary motor 10 (see FIG. 3).
That is, the resistor 8 advances (when the auxiliary motor is rotating normally) or retracts (when the auxiliary motor is rotating backward) about its axis 8a. Further, 11 is a white rice discharge port, and 12 is an electric equipment box, which incorporates the control circuit shown in FIG. In addition, this control circuit has a lamp 13 that indicates that rice is being polished and an indicator that displays the desired whiteness.
14, key operation panel for inputting various commands and data 15
(See FIG. 3 for both) and so on. further,
Reference numeral 16 denotes a whiteness sensor incorporating a light emitting element and a light receiving element, which detects the whiteness of the rice 2 in the rice polishing tank 1 through the transparent plate of the rice polishing tank 1.

In the rice milling machine of FIG. 2, the flow resistance of the grain is adjusted by adjusting the resistor 8 under the drive of the main motor 5, whereby rice polishing is performed. The control circuit 12 controls the auxiliary motor 10 for adjusting 5 and the resistor 8.

Referring to FIG. 3, the load current Il of the main motor 5 is supplied to the A / D converter 1201 via the current detector 1200, the output of the whiteness sensor 16 is supplied to the A / D converter 1202, and the power is supplied. 17 is supplied to the A / D converter 1204 after being reduced in voltage by the transformer 1203. The input of the power supply 17 is for determining whether the power supply 17 is a 50 Hz power supply or a 60 Hz power supply by measuring the time between peaks of the output waveform from the transformer 1203. The fixed data (table) such as the setting reference value of the proper load current Il of the main motor 5 is switched or corrected, but a manual switch may be provided and supplied to the input / output interface 1205. In addition,
In the examples described below, the description of switching between 50 Hz and 60 Hz is omitted.

In addition, the input / output interface 1205 has an auxiliary motor 10
Drive circuit 12 for forward (forward) or reverse (backward) rotation
06, a drive circuit 1207 for driving the lamp 13, a drive circuit 1208 for driving the display 14, a key control circuit 1209 for controlling the input of the key operation panel 15, etc. are connected. In addition, the 1210
Control circuit 1 based on the program and fixed data in ROM1211
2 CPU that controls the whole, 1212 stores temporary data
RAM.

Next, the operation of the control circuit shown in FIG. 3 will be described.

FIG. 4 is a flow chart showing the first embodiment, and FIG. 5 is its load characteristic diagram. This routine is started, for example, by turning on a rice polishing start button (not shown). In step 401, the main motor 5 is turned on to rotate the rice polishing screw 4. As a result, the rice 2 moves as shown by the arrow in FIG. Next, at step 402, the auxiliary motor 10 is rotated in the forward direction to advance the resistor 8 to raise the pressure in the pressure chamber 9. This corresponds to the operation at time t ₀ in FIG. At this time, the lamp 13 is turned on to indicate that rice is being polished.

Next, in steps 403 and 404, the time t ₁ is measured. That is, the timer T ₁ is cleared at step 403, the timer T ₁ is waiting for the arrival time t ₁ at step 404. The timer T ₁ is stepped by a routine (not shown) executed every predetermined time.

When the time t ₁ has elapsed, the routine proceeds to step 405, where the auxiliary motor 1
Stopping forward rotation of 0 (corresponding to time t ₁ of FIG. 5). In this way, the resistor 8 is fixed after advancing by a predetermined amount, and the pressure of the predetermined pressure chamber 9 becomes a predetermined value. In steps 404 and 405, the load current Il of the main motor 5 may be detected, and the resistor 8 may be advanced until the load current Il reaches an appropriate load current value and then fixed.

Next, at step 406, the maximum value of the load current Il is detected. That is, the load current Il at every predetermined time is A / D converted and taken in, and the maximum value is detected by changing the sign of the change amount ΔIl from positive to negative. That, rice bran with the progress of milling is stripped, this result, the rice grains of the friction is increased load current Il of the main motor 5 is increased, the time of FIG. 5 t ₂
To reach maximum load.

After that, the action of removing the peeled rice bran becomes large, and the load current Il of the main motor 5 decreases. The increase / decrease in the load current Il depends on the balance between the amount of rice bran generated by pearling and the amount of rice bran removed from the bran removal net 6. When the degree of whitening increases, the amount of rice bran generated decreases, and when the degree of whitening approaches 100%, there is almost no decrease in the load current Il of the main motor 5. That is, in steps 407 to 412, it is determined that the decrease in the load current Il of the main motor 5 has almost disappeared and the rice polishing is stopped. That is, in step 407, the timer T ₁ is cleared, and in step 408, it waits for the predetermined time Δt to elapse. Then, in step 409, the load current Il of the main motor 5 is A / D converted and taken in, and the reduction amount ΔIl (= Il ₀ −Il) is calculated, and in step 410 the load current Il is set to Il ₀ , In step 411, it is determined whether the reduction amount ΔIl is less than the predetermined value α. The flow of steps 407-411 is △
Repeat until Il <α. As a result, the time shown in FIG.
As shown in t ₃ , when ΔIl <α, step
Proceed to 412 to stop rice polishing. The rice polishing is stopped by reversing the auxiliary motor 10 and moving the resistor 8 backward, and at the same time, the lamp 13 is turned off and the main motor 5 is also turned off. If you want to polish the polished rice, move the resistor 8 backwards,
Delay for ~ 10 minutes, then turn off the main motor. Also,
When a desired whiteness of 110%, for example, is required, a step is provided between step 411 and step 412 for delaying a predetermined time, for example, 100% of the whitening time of 30%, which is 10% for 3 minutes. Good.

Then, in step 413, the routine of FIG. 4 ends.

In the first embodiment shown in FIG. 4, the whitening completion is determined by the decrease amount ΔIl of the load current Il of the main motor 5 per predetermined time, but the determination is made according to the change in the load current characteristic and the gradient. You can also do For example, as shown in FIG. 6, the relative change ΔIl ₁ /
It may be determined whether or not ΔIl ₀ is equal to or less than a predetermined value, for example, 0.6. According to the determination of such relative changes, the moisture content of the rice, the content rate of the unripe rice, the variety, the amount of the rice to be poured into the rice polishing tank 1, the setting level of the resistor 8, the difference between the polished white rice and the polished white rice, etc. Therefore, it is possible to appropriately respond to changes and gradients of different load characteristics. For example, when the rice bran is remarkably generated (FIG. 7 (A)) or the rice bran is difficult to peel (FIG. 7 (B)), it is possible to highly accurately determine the completion of polishing.

FIG. 8 is a flow chart showing the second embodiment, and FIG. 9 is a load characteristic diagram thereof. Step 801, 80 in FIG.
8,809 is the same as 401, 412, 413 in FIG. In the routine of FIG. 8, the load current Il of the main motor 5 is set to the maximum value MA.
The amount of protrusion of the resistor 8 is controlled so as to be between X and the minimum value MIN. That is, in step 802,
The auxiliary motor 10 is normally rotated to advance the resistor 8, and in step 803 it is determined whether or not the load current Il of the main motor 5 has reached the maximum value MAX. As a result, the load current Il of the main motor 5
When becomes the maximum value MAX, the auxiliary motor 10 is turned off in step 804. In this way, the load current of the main motor 5
The resistor 8 advances and is fixed until Il reaches the maximum value MAX, so that the load current Il of the main motor 5 naturally decreases thereafter.

Next, in steps 805 to 807, the load current Il of the main motor 5 is
Measures the time T ₂ required to reach the minimum value MIN. That is, the timer T ₂ is cleared in step 805, and step 8
At 06, it is determined whether the load current Il of the main motor 5 has reached the minimum value MIN. As a result, when the load current Il of the main motor 5 reaches the minimum value MIN, it is determined in step 807 whether the time T ₂ is greater than the predetermined value t _R. In addition, timer T
Similarly to the timer T ₁ described above, ₂ is stepped by a routine that is executed at predetermined time intervals (not shown). T ₂
If ≦ t _R , the flow of steps 802 to 806 is repeated. The gradient of the drop of the load current Il during this period is gentle at the beginning as shown in FIG. 9, becomes steep in the middle, and becomes very gentle in the whitening finish. Therefore, the completion of whitening can be determined by the time T ₂ of the descending gradient. That is, when T ₂ > t _R in step 807, the process proceeds to step 808 to finish the rice polishing. Also in this case, as in the case of the first embodiment, it is possible to delay the end of rice polishing in step 808 to further raise the whitening degree.

Also in the second embodiment, the change of the load current characteristic,
In order to perform the determination according to the gradient, for example, as shown in FIG. 9, it is determined whether the relative change T ₂ ′ / T ₂ of the time T ₂ of the descending gradient at a predetermined time T is a predetermined value, for example, 0.6 or less. You may.

FIG. 10 is a flow chart showing the third embodiment.
Figure 11 is the load characteristic diagram. Step 1001,1 in Figure 10
009 and 1010 are the same as 401, 412 and 413 in FIG. In the routine shown in FIG. 10, the main motor 5 is driven every predetermined time Δt '.
The advancing of the resistor 8 is controlled so that the load current Il becomes the maximum value MAX. That is, in step 1002, the auxiliary motor 10 is normally rotated to advance the resistor 8, and in step 1003, it is determined whether or not the load current Il of the main motor 5 has reached the maximum value MAX. As a result, when the load current Il of the main motor 5 reaches the maximum value MAX, the auxiliary motor 10 is turned off in step 1004. In this way, the resistor 8 advances until the load current Il of the main motor 5 reaches the maximum value MAX.

Next, in step 1002 and 1003, the timer T ₃ by a time △
Then, t'is measured, and in step 1004, a difference ΔIl from the maximum value MAX of the load current Il of the main motor 5 is calculated every time Δt '. Then, in step 1005, it is determined whether or not ΔI ₁ <β (predetermined value), and if ΔIl ≧ β, steps 1002 to 1007
The flow of is repeated. That is, as shown in FIG. 11, when the auxiliary motor 10 is normally rotated at every time Δt ′ to make the load current Il of the main motor 5 the maximum value MAX, the increase degree ΔIl of the load current Il is the removal of rice bran. The effect gradually reduces. Therefore, the completion of whitening can be determined by ΔIl <β. Therefore,
When ΔIl <β, the process proceeds to step 1009 to finish the rice polishing. Also in this case, as in the first embodiment, step 10
It is also possible to delay the end of rice polishing in 09 to raise the degree of milling.

Also in the third embodiment, the change of the load current characteristic,
In order to perform the determination according to the gradient, for example, the determination may be made based on whether or not the relative change of the degree of increase ΔIl in a predetermined time is a predetermined value, for example, 0.6 or less.

FIG. 12 is a flowchart showing the fourth embodiment.
Figure 13 is the whiteness characteristic diagram. Steps 121 and 12 in FIG. 12
4,125 is the same as 401,412,413 in FIG. As the auxiliary motor control in step 122 of the routine shown in FIG. 12, any of the above-mentioned auxiliary motor controls may be used. That is,
In step 123 of FIG. 12, the output of the whiteness sensor 16 is A / D converted and taken in, and the preset whiteness a is set in advance.
It is determined whether or not it is higher, and when the whiteness> a, step 12
Proceed to 4 to finish rice polishing. As shown in FIG. 13, the time tb of whiteness b at which the whiteness suddenly changes is detected and
It terminates the rice in tb constant multiplied by time (corresponding to t ₃₎ also, or detects the time tc of the inflection point c of whiteness, also corresponds to the time tc constant multiplied by time (t ₃ ) Can finish the rice polishing.

〔The invention's effect〕

As described above, according to the present invention, the milling degree of rice is indirectly or directly detected, and the milling is completed based on this. It is possible to prevent insufficient or excessive whitening.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is an overall configuration diagram of a rice polishing machine according to the present invention, FIG. 3 is a detailed block circuit diagram of the control circuit of FIG. 2, and FIG. FIG. 5 is a flow chart showing the operation of the control circuit as the first embodiment of the invention, FIG. 5 is a load characteristic diagram for supplementarily explaining the operation of FIG. 4, and FIG. 6 is a load for explaining the modified example of FIG. 7 is a characteristic diagram, FIG. 7 (A), (B) is a load characteristic diagram for explaining the effect of the operation of FIG. 4, and FIG. 8 shows the operation of the control circuit as the second embodiment of the present invention. Flowchart, FIG. 9 is a load characteristic diagram for supplementarily explaining the operation of FIG. 8, FIG. 10 is a flowchart showing the operation of the control circuit as the third embodiment of the present invention, and FIG. 11 is the operation of FIG. FIG. 12 is a load characteristic diagram for supplementary explanation, and FIG. 12 is a flow chart showing an operation of a control circuit as a fourth embodiment of the present invention. FIG. 13 is a whiteness characteristic diagram for supplementarily explaining the operation of FIG. 1 ... rice polishing tank, 2 ... rice, 4 ... rice polishing screw, 5 ... main motor, 8 ... resistor, 9 ... pressure chamber, 10 ... auxiliary motor, 16 ... whiteness sensor.

Continuation of the front page (56) References JP-A-60-137445 (JP, A) JP-A-57-21943 (JP, A) Actual development Sho-62-21334 (JP, U)

Claims (4)

[Claims] 1. A rice milling machine provided with a main motor for driving a rice milling screw for feeding rice into a pressure chamber and an auxiliary motor for moving a resistor for adjusting a whitening pressure in the pressure chamber. In the controller of the rice polishing machine that adjusts the whitening pressure by moving and fixing the operation of the resistor based on the load of the main motor during the whitening of the rice, after fixing the operation of the resistor, A whitening degree detecting means for continuously detecting a change in the load of the main motor, and calculating a temporal change amount accompanying the load change of the main motor from the detected load of the main motor and its detection interval; A control unit for a rice polishing machine, comprising: a polishing degree determining means for determining a polishing degree of the rice by comparing the amount of temporal change with a predetermined value associated with the rice to be pumped. 2. The control according to claim 1, further comprising stop means for terminating the whitening of the rice when the determined whitening degree reaches a predetermined value associated with the rice. apparatus. 3. The fixing of the resistor is performed after a predetermined time has elapsed from the start of the whitening of the rice or when the load of the main motor reaches an appropriate value for the whitening of the rice. The control device according to claim 1 or 2. 4. When the peak of the change in the load of the main motor is detected after fixing the resistor, the whitening degree detecting means determines the amount of change in the load of the main motor with time or absolute value. The control device according to claim 1 or 2, wherein the whitening degree is calculated by a relative value, and the whitening degree determining unit determines the whitening degree from the calculated temporal change amount.