JPH04135651A - Rice milling machine - Google Patents

Abstract

PURPOSE:To perform milling of unpolished rice at the various degrees of milling with high reliability by equipping a supply means for supplying unpolished rice to a milling chamber, a means for regulating the discharge port of polished rice which is provided to the outflow region of polished rice in the milling chamber and a torque sensor for detecting the load of the inside of the milling chamber and controlling the means for regulating the outflow of polished rice in accordance with the detection value due to the torque sensor. CONSTITUTION:When unpolished rice is introduced into a casing 2 of the upper part from a hopper 7 by a screw conveyor 6, unpolished rice is intruded into a milling cylinder part 3 by a feeding roll 10, milled and treated between a rotated milling roll 11 and a net 17. Separated bran is discharged to the outside together with the air current which passes through the net 17 and flows toward the discharge hole 18 of bran. The polished rice is successively carried out through an annular discharge port formed between the external periphery of an opening regulation member 15 described hereunder and an outlet forming member 19 for polished rice. Thereafter the polished rice is discharged to the outside via a chute 21 from a discharge port 20. The opening regulation member 15 resists the force of a spring 33 bias-regulated by an elevation means 35 and is pushed down by the pressure of the inside of the milling chamber. Herein this pressure of the inside of the milling chamber is detected by a torque sensor 25 as the load of the inside of the milling chamber for the rotary shaft 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides a method for discharging a milling chamber with a driven milling roll when the internal load of the milling chamber exceeds a preset biasing force by a biasing means. The present invention relates to a rice milling machine that is opened and discharges polished brown rice, and a method of controlling the rice milling machine.

[Conventional technology]

A conventional rice milling machine is configured as shown in FIG. 10, for example.

Inside the polishing tube (501), there are a feed roll (502),
A whitening roll (503) is installed, and a whitening cylinder (50
At the outlet of 1), there is a resistance plate (504) that limits the cross-sectional area of the passage.
) is provided. The rice polishing process is carried out using feed rolls (502
) and a polishing roll (503) are driven to rotate by a motor (505), and the brown rice (506) introduced from the top is pushed toward the resistance plate (504) by the feed roll (502), and the polishing cylinder (1) is driven. The brown rice is polished between the inner net (509) and the rotationally driven rice polishing roll (503), and the polished white rice is discharged from the white rice outlet (507). When the opening degree of the polished rice outlet (507) is made small, the internal load of the milling chamber becomes high and the whiteness becomes high, and when the opening degree is made large, the internal pressure becomes low and the whiteness becomes low.

Conventionally, in order to maintain a constant level of polishing, the polished rice outlet (5
The resistance plate (504) is moved in the direction of closing the spring (50).
The pressing in 8) is done by applying force, and the resistance plate (
504) when a force exceeding the above-mentioned urging force acts on
The opening degree of the polished rice outlet (507) is increased to discharge polished rice having a specified level of polishing from the polishing tube 1.

However, the operation of adjusting the biasing force of the spring (508) to achieve the desired degree of sharpness requires skill and has poor operability.

Therefore, as seen in Japanese Patent Publication No. 1-12542,
Detecting the current value to the motor (505) with a current transformer,
A technique is known that automatically controls an actuator (not shown) that varies the biasing force of the spring (50B) so that the detected current value approaches a set value necessary to obtain a specified degree of polishing.

However, control based on the current value has poor control accuracy due to fluctuations in the power supply voltage and variations in the characteristics of the motor (505).

Furthermore, in the past, even if the polishing degree could be automatically controlled, the polishing tube (1
) is not equipped with any means to determine and display that there is little unprocessed brown rice left in the rice mill ( ) and that the rice milling is complete. Currently, the operation of the motor (505) is continued, and the operation of the motor (505) is stopped when the staff feels that there is enough rice. Unpolished brown rice is discharged without being polished, and in order to prevent this, it is known from JP-A No. 62-227459 that a circulating transfer path is purposely provided to re-supply the initially discharged processed rice to the rice milling machine. ing.

Furthermore, in the conventional horizontal type rice milling machine described above with reference to the drawings, the biasing force of the spring (508) is kept constant from the start to the end of the rice milling operation. Therefore, as polishing approaches the end, there is less brown rice (506) left to be sent to the milling chamber 1, and the internal load of the milling chamber (501) decreases.
As the polishing becomes insufficient, the white rice cannot flow out,
The final supply remains in the milling room. On the other hand, in the case of vertical installation where gravity is applied, if the internal load of the polishing chamber decreases at the end of polishing, the desired degree of polishing cannot be achieved, and the resistor plate (504) is opened and the polished rice is removed. If it is discharged from the outlet (507), those that have not been sufficiently polished will be discharged.

[Problem to be solved by the invention]

An object of the present invention is to provide a rice milling machine and a control method thereof that can mill brown rice at various milling degrees with high reliability. Furthermore, it is an object of the present invention to eliminate the inconveniences that occur in conventional rice milling machines at the initial stage and final stage of the polishing process.

[Means to solve the problem]

The rice milling machine and the rice milling technology related to its control according to the present invention are as follows:
We focused on the fact that highly reliable milling is possible by accurately monitoring the internal load of the milling room, and based on our success in reliably and accurately obtaining this internal load by using a torque sensor. There is. That is, in order to solve the above problems, the rice milling machine according to the present invention has the following configuration; (a) a milling chamber equipped with milling rolls that mill brown rice into white rice; (b) brown rice in the milling chamber; Brown rice supply means for supplying (c
) a polished rice outlet adjusting means provided in a polished rice outflow area of the whitening room; (d) a torque sensor for detecting an internal load of the whitening room; (e) a means for adjusting the whitened rice outflow according to a value detected by the torque sensor control means for controlling the internal load of the whitening room at a preset value;

Furthermore, in order to solve the above problem, when the internal load of the milling chamber equipped with the driven milling roll exceeds the biasing force preset by the biasing means, its discharge port is opened and polished brown rice is discharged. Regarding the method of controlling the rice milling machine, the method according to the present invention consists of the following steps; (1)
) selecting the degree of polishing, (2) supplying brown rice to the milling chamber, (3) setting the biasing force based on the selected degree of polishing, (4) measuring the internal load of the milling chamber using a torque sensor. (5) adjusting the biasing force of the biasing means based on the detected value by the torque sensor in order to maintain the internal load value set corresponding to the selected polishing level; (6) ) determining the end of supply of brown rice to be milled when the detected value by the torque sensor indicates a predetermined internal load state of the milling chamber.

[For production]

The rice milling technology according to the present invention described above controls the supply of brown rice and the discharge of white rice based on the detected value of a torque sensor provided to accurately monitor the internal load of the milling room, thereby achieving the desired level of milled rice. Treatment is obtained.

〔Effect of the invention〕

The degree of polishing in the milling process is closely related to the internal load of the milling room, so by using a torque sensor, it is possible to mill rice with a highly reliable degree of polishing based on the internal load that is detected with high accuracy. became. In particular, even when whitening has to be carried out with various degrees of whitening,
By extremely accurately maintaining the internal load of the milling chamber corresponding to the selected milling degree by monitoring the torque detection value by the torque sensor, the quality of milled white rice is made uniform.

[Other features]

Furthermore, the inconveniences in the initial whitening process and the final whitening process in the prior art described above can also be resolved by adjusting the brown rice supply and the white rice outlet using the torque detection value by the torque sensor as a trigger. Therefore, in the whitening process according to the present invention, the whitening process is divided into initial whitening process, main whitening process, and final stage whitening process, and the control suitable for each process monitors the internal load of the whitening room, that is, the detected value of the torque sensor. It is done while In order to achieve these objectives, the following is proposed as a preferred embodiment of the rice milling machine according to the present invention: 1. The control means is provided with a polishing degree setting means, and the polishing degree setting means is provided in the control means. The white rice outflow adjusting means is controlled to maintain an internal load value of the whitening room corresponding to the whiteness level selected by the whitening means.

2. The polished rice outflow adjusting means includes a fixed outer discharge port forming member and a movable inner discharge port forming member, and changes the cross-sectional area of the inner discharge port forming member as the inner discharge port forming member moves between the two members. An outlet is formed.

3. The inner discharge port forming member is urged in the direction of closing the discharge port by a biasing means, and is moved in the direction of opening the discharge port against the biasing force by an internal load of the milling chamber, and The means changes this biasing force according to the detected value of the torque sensor. The biasing means is constituted by a spring, and the control means can change the bias value of this spring.

4. The control means includes a torque value setting means for initial whitening process and a timer for initial whitening process, and when the whitening chamber is almost filled by the brown rice supply means, the value detected by the torque sensor is set for the initial whitening process. The brown rice supplying means is intermittently stopped or decelerated until the torque value is exceeded, and then polishing is performed with the supplying means stopped for the set time of the initial polishing timer.

5. The control means includes a terminal milling process determination unit that determines whether to terminate the supply of brown rice to be milled when the detected value by the torque sensor indicates a predetermined internal load state of the milling chamber; When the processing determination unit determines that the supply of brown rice has ended, the polished rice discharge port adjustment means is configured to perform milling while temporarily suppressing the discharge of white rice from the milling chamber, and then discharge the polished rice from the milling chamber. control. At this time, the terminal polishing process determining section determines to end the supply of brown rice when the detected value by the torque sensor is less than a predetermined lower limit value. Alternatively, the terminal polishing process determining section may determine that the supply of brown rice has ended when the value detected by the torque sensor exceeds a predetermined negative rate of change.

〔Example〕

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

In Fig. 1, l is the main casing, and the upper casing (2), milling cylinder part (3), intermediate casing (4) and lower bearing casing (5) are fitted and connected in order from the upper part to the lower part. are constructed so that their axes coincide. A screw conveyor (6) serving as a brown rice supply means for supplying brown rice to an opening formed in the upper side wall of the upper casing (2) is connected. 7 is a hopper for charging the brown rice, and 8 is a drive motor for the screw conveyor.

Reference numeral 9 denotes a rotary shaft that is erected at the center over the upper part of the upper casing (2), the milling cylinder part (3), and the intermediate casing (4), and is formed as a hollow shaft.

A feed roll (10) is placed in the upper casing (2) area of this rotating shaft (9), and a whitening roll (1) is placed in the whitening cylinder part (3) area.
1) is installed.

The feed roll (10) and the whitening roll (11) are connected to each other by a connecting pin (12), and the whitening roll (
11) is circumferentially engaged with the rotating shaft (9) by a key (13) at a position near the lower end. You can also use refined rolls (
A cylindrical recess 14 is formed at the lower end of 11), into which a fitting cylindrical part (16) extending from the upper part of the opening regulating member (15) is fitted so as to be vertically slidable. The outer peripheral surface of the opening degree regulating member (15) is formed into a cylindrical surface having an appropriate width in the vertical direction. Further, the fitting cylinder part (16) has an inner peripheral surface tapered downward so that the upper end has a pointed shape, and a space is formed between the fitting cylinder part (16) and the outer peripheral surface of the rotating shaft (9). The bran adhering to the circumferential surface of the cylindrical recess (14) at the lower end of the whitening roll (11) is scraped off, and the cylindrical recess (14)
) and the upper end of the fitting cylinder part (16) so that no bran is caught between the bottom surface of the fitting cylinder part (16) and the upper end of the fitting cylinder part (16). Inside the polishing cylinder part 3, a net (17) is arranged at an appropriate interval around the outer periphery of the polishing roll (11), and at the bottom of the side wall of the polishing cylinder part (3) there is a screen for draining the bran generated during polishing. The outlet (18) is open. Furthermore, the lower end of the polishing cylinder part (3) and the intermediate casing (
A polished rice discharge port forming member (19) is disposed between the upper end of the polished rice discharge port 4). The inner periphery of the polished rice discharge port forming member (18) is formed into a knife shape, and is in contact with the outer periphery of the opening degree regulating member (15) having an appropriate width in the vertical direction.

At the upper end of the side wall of the intermediate casing (4) is a white rice outlet (2
0) is formed, and a chute (21) is attached here. In addition, the rotating shaft (9) is equipped with a polished rice outlet forming member (
A receiving plate (22) is provided in a protruding manner to receive the polished rice falling from the chute (21). An intermediate shaft (23) rotatably supported by a pair of upper and lower bearings (24) is disposed in the intermediate portion of the intermediate casing (4), and is fitted and fixed to the lower end of the rotating shaft (9). . A torque sensor (25) is arranged at the lower part of the intermediate casing (4), and an upper shaft part (25a) protruding from one end of the torque sensor (25) is attached to the intermediate shaft (25).
23) so as to be slidable only in the axial direction.

Inside the lower bearing casing (5) are a pair of upper and lower bearings (26
) is arranged such that the drive shaft (27) is rotatably supported by the drive shaft (27), and its upper end is slidable only in the axial direction with respect to the lower shaft part (25b) protruding from the other end of the torque sensor (25). It is fitted. Further, a drive pulley (28a) is fixed to the lower end of the drive shaft (27). This drive pulley (28
a) is rotationally driven by a motor (28), not shown in detail, via a drive belt (28b).

The opening adjusting shaft (29) is inserted into the hollow rotating shaft (9), and its lower end and the opening regulating member (15) are inserted into the elongated hole (31) formed in the hollow rotating shaft (9). The connecting member that passes through (
30). The upper end of the opening adjustment shaft (29) is relatively rotatably engaged with the upper surface of a retaining member (34) supported on the elevating member (32) via a spring (33). The lifting member (32) is connected to the lifting means (32), which is shown schematically in FIG.
35) so that it can be moved up and down.

As shown in FIG. 2, the elevating means (35) includes a feed screw shaft (38) rotationally driven by a drive motor (37), a movable nut body (39) screwed thereto, and its guide. It is composed of a rod (40), and a movable vertical body (39) is connected to an elevating member (32). That is, the bias tension of the spring (33) can be adjusted by the lifting means (35). In other words, the elevating means (35), the retaining member (34), the spring (33), the elevating member (32), the opening adjustment shaft (29), the polished rice outlet forming member (19), and the opening regulating member ( 15) constitutes a polished rice outlet adjustment means.

In the rice milling machine configured as described above, the drive pulley motor (28) connects the drive shaft (27) and the torque sensor (2).
When the brown rice is fed from the hopper (7) into the upper casing (2) by the screw conveyor (6) while the rotating shaft (9) is rotationally driven through the feed roll (
10), and is pushed into the whitening cylinder part 3 and subjected to whitening treatment between the rotating whitening roll (II) and the net (17). The rice bran separated during the whitening process is caused by the air introduced into the rotating shaft (9) and the whitening roll (1).
1) through a through hole (not shown) protruding from the net (17).
The rice bran is discharged to the outside along with an air flow flowing through the bran discharge hole (18). The polished rice is stored in the space between the net (17) of the polishing tube part (3) and the polishing roll (11),
In other words, the elevating means (35) is raised and lowered by the pressure inside the whitening chamber.
The rice is sequentially discharged from an annular discharge opening formed between the outer periphery of the opening regulating member (15) pushed down against the force of the spring (33) bias-adjusted by the milled rice outlet forming member (19), and After that, the chute (
21) and is discharged to the outside. Here, the pressure inside the whitening chamber is detected by the torque sensor (25) as the internal load of the whitening chamber on the rotating shaft (9).

FIG. 3 shows a control block diagram of the rice milling machine according to the present invention. The signal from the torque sensor (25) mentioned above is input, and the motor (8) for the screw conveyor (6) is activated.
) and the motor (37) and rotating shaft (9) for the lifting device (35), that is, the feed roll (10) and the polishing roll (11).
A control means (36) that outputs a control signal to the motor (28) for the rice milling machine plays a central role in controlling the rice milling machine. The control means (36) employs a normal microcomputer control method, and includes a CPU (100),
ROM (103), RAM (104), input interface (101), output interface (10
2), etc., and is also provided with polishing degree selection means (200) for selecting a desired degree of polishing in order to mill rice at various degrees of polishing in this rice milling machine. Here, the brightness selection means (200) has four modes, ie, "upper white" mode, "white" mode, "seven" mode, and "five"
Preparing the mode. Of course, instead of this, it is also possible to configure so that the degree of polishing can be selected steplessly.

The CPU (100) processes torque detection signals sent from the torque sensor (25) and precision selection means (200).
Based on the polishing mode selected by ROM
(103) according to the control algorithm stored in the motor (8) for the screw conveyor (6), the motor (37) for the lifting device (35), and the rotating shaft 9. A control signal is output to the motor (28) to control the polishing process.

The control flow of the whitening process of the rice milling machine according to the present invention will be explained below using the flowcharts shown in FIGS. 4 to 8. What is shown in Figure 4 is a flowchart showing the main routine of this rice milling machine. First, the operator must select the desired degree of milling, that is, the milling processing mode (#0), and press the start button to mill the rice. When the process starts, the lifting means (35) is driven to release the spring (3).
3) Adjust the bias and set P m to the opening adjustment shaft (29).
Set the biasing force of in (#2). Drive the motor (28) to rotate the polishing roll (11) and feed roll (10) (#4), take in the detected value of the torque sensor in this state, that is, the no-load torque value = To, and store it in the RAM (104).
(#6). Detection by the torque sensor (25) is actually repeatedly performed at appropriate time intervals in torque detection interrupt processing, which will be explained later, and the detected value is stored in the RAM (10
Since it is stored at the predetermined address of 4), the detected torque value can be retrieved from there in the control routine. Next, the biasing force of the opening adjustment shaft (29) is set to Pmax, which is a higher value than Pm1n (#8). From this point, the actual whitening process begins, which is divided into initial whitening process (#10), main whitening process (#12), and final whitening process (#14), which will be explained in detail later.

As shown in FIG. 5, the torque detection interrupt processing described above takes in the detected torque value 2T ($1100) from the torque sensor (25) and uses the moving average method from this detected value and the previously taken detected value. Calculate the average torque value: Tm using #1200), and from this average torque value: Tm #
Subtract the no-load torque value taken in step 4 = TO and get the coefficient: K
Calculate the threshold value: S by multiplying by #1300),
These values, T, and Tm5S are stored in a predetermined address of the RAM (104) (#1400).

Next, the initial whitening process will be explained using FIG. 6; first,
The screw conveyor (6) is started operating in the first mode in which the conveyance amount is large (#50), and brown rice is introduced from the hopper (7) into the internal space of the milling cylinder (3), that is, the milling chamber. After the time set by the first timer, during which the milling chamber is almost filled with the supplied brown rice (#52, #54), the screw conveyor (6) is stopped (#56). Next, the operation is restarted in the second mode in which the conveyance amount is small (#6
4) Compare the torque detection value of the torque sensor (25) with a preset reference value: Tob #60, #62)
, When the detected value exceeds Tab, it is assumed that the milling room is completely filled with brown rice and the screw conveyor is stopped (#6
4). In this state, whitening is performed in the whitening room for the time set by the second timer (#66, #68). It is preferable to control the screw conveyor so that the first mode described above is continuous operation and the second mode is intermittent operation, or alternatively, the first mode is high speed operation and the second mode is low speed operation. It is also possible to do this. Furthermore, instead of setting the operating time of the first mode with a timer, it is also possible to control the operation until a predetermined load value, that is, the detected torque, is obtained while monitoring the internal load of the milling room using a torque sensor. It is.

In this initial polishing process, the biasing force against the opening adjustment shaft (29) is adjusted to be high, so that unpolished brown rice is not released. For the white rice polished during this period, the supply of brown rice by the screw conveyor is resumed in the next main milling process, and the pressure of the supplied brown rice pushing into the milling chamber causes the opening adjustment shaft (29), that is, the opening regulating member ( 15) descends downward, and a discharge port is formed between the opening degree regulating member (15) and the polished rice discharge port forming member (19), whereby polished rice is discharged from this discharge port.

Next, the main whitening process will be explained using FIG. 7: First, the whitening mode selected by the whitening degree selection means (200) is checked (#100), and in the case of "top white" mode, the whitening mode is checked from #110 to #. Based on steps 160 for "White" mode #Based on steps 210 to #260 for 'Seven minutes' mode #Based on steps from #310 to #360 for 'Five minutes' mode # 410 to #4
Respective whitening treatments are performed based on 60 steps.

For example, if the 'upper white' mode is selected, the motor (37) of the lifting means (35) is not driven (33).
, and set the biasing force applied to the opening adjustment shaft (29) to Pl suitable for the "upper white" mode (#
110). Next, the screw conveyor (6) is started operating in the third mode (#120), and new brown rice starts to be supplied to the milling room. This third mode of operation is a so-called steady continuous operation of the screw conveyor (6), and the specifications etc. of the motor (8) of the screw conveyor (6) are normally determined based on the load etc. during this operation. In the polishing process that starts from this, the torque value detected by the torque sensor (25) is compared with the reference torque range for the "upper white" mode, that is, the lower limit value: Tla and the upper limit value: Tlb (#130 ). There is a correlation between the degree of polishing of white rice and the internal load of the milling room during milling, that is, the detected torque value, and by accurately controlling the internal load of the milling room, it is possible to obtain the desired degree of polishing of brown rice. This is because it can be refined. If the detected torque value 2T is smaller than the lower limit Tla, control the lifting means (35) and increase the biasing force of the opening adjustment shaft) L (# 140)
), If the detected torque value T is larger than the upper limit value TIb, the lifting means (35) is controlled to decrement the biasing force of the opening adjustment shaft #150), and the detected torque value T is lower limit value Tla. Upper limit value: If it is between Tlb, the biasing force of the opening adjustment shaft remains unchanged. That is, when the internal load of the whitening chamber increases and the load torque acting on the whitening roll (11) increases, the torque value 2T detected by the torque sensor becomes larger than the upper limit value: Tlb. In this case, the control signal from the control means (36) causes the elevating means (35) to
is driven, and the elevating member (32) is lowered. As a result,
The upward biasing force of the opening adjustment shaft (29) by the spring (33) decreases, and the opening adjustment shaft, that is, the opening regulation member (15) descends, forming a space between it and the polished rice discharge opening forming member (19). The flow cross-sectional area of the outlet is increased. Therefore, the internal load of the whitening room is reduced. Conversely, when the internal load of the whitening room becomes small, the flow cross-sectional area of the outlet becomes smaller through the same procedure, and the internal load of the whitening room increases. In this way, by keeping the torque detection value of the torque sensor constant, accurate polishing degree, that is, polished rice that matches the selected polishing mode can be obtained. During such main polishing process, the above-mentioned average torque value: Tm or threshold value:
If it is below S, all the brown rice put in the hopper (7) is supplied to the milling room, and it is determined that there is no more brown rice to be supplied (#160), this main milling process is finished, and the next terminal milling process is started. Move to processing.

So far, we have described the main whitening process in the "upper white" mode,
Processing in other whitening modes is performed in the same way. However, in the "white" mode, the urging force at #210 is set to P2, and the lower limit value of the detected torque at #23o is replaced by the lower limit value 72a and the upper limit value T2b. Similarly, in the "seven minutes" mode, the urging force at #310 is set to P3, and the biasing force at #330 is set to P3.
The lower limit value of the detected torque is replaced by T3a, and the upper limit value is replaced by Tab. In the '5 minutes' mode, the biasing force at #41O is set to P4, and the lower limit of the detected torque at #430 is T.
The upper limit value of 4a is replaced with T4b.

Next, the terminal whitening process will be explained using FIG. 8; First,
The elevating means (35) is controlled to increase the biasing force against the opening adjustment shaft (29), and set it to, for example, Pmax, and (
#500), stop the screw conveyor (6). Since the biasing force against the opening adjustment shaft (29) is suddenly increased, the flow cross section of the outlet is also reduced and the discharge of polished rice is suppressed. In this state, after the whitening process by rotating the whitening roll (11) continues for the time set by the third timer (#
520, #530), that is, when the brown rice in the milling room is almost polished, reduce the biasing force against the opening adjustment shaft (29) and set it to, for example, Pm1n (
#540), the opening adjustment shaft (29) is lowered, and as a result, the flow cross section of the discharge port is expanded, and the white rice in the milling chamber is discharged. The time for the rice to be completely released from the milling chamber is set in advance on the fourth timer, and when the fourth timer times up (#520, #530), the rotation shaft (9
), or as a result, the feed roll (10), whitening roll (1
1) is stopped (#570), and a series of whitening processes is completed. To summarize the control flow of these series, this control consists of 1) selecting the degree of polishing, 2) stopping the supply of brown rice to the milling chamber when the milling chamber reaches a predetermined internal load; 3) a main whitening process step in which whitening is carried out while maintaining an internal load corresponding to the selected degree of whitening; 4) a predetermined low internal load state or reduction of the whitening chamber; It is understood that this process consists of a terminal polishing step in which the release of polished rice is suppressed for a certain period of time when an internal load of 100% is present.

As described above, the rice milling machine according to the present invention monitors the internal load of the milling chamber using a torque sensor and maintains it at a predetermined value after appropriately setting the biasing force on the opening adjustment shaft (29). It is possible to perform whitening with an accurate degree of whitening. Furthermore, by setting the biasing force on the opening adjustment shaft (29) and monitoring the internal load of the milling chamber using a torque sensor, it is possible to improve the milling process at the start and end of milling, which has been difficult in the past. In order to easily understand this control principle, a graph showing the relationship between the polishing process and the torque detected by the torque sensor is shown in FIG.

At the time of X00, the rice milling machine is in no-load operation.

At the time of Xl, the biasing force of P max is applied to the opening adjustment shaft (29)
The supply of brown rice by the screw conveyor (6) is started. The detected torque value gradually increases, and at the time of X2, the polishing chamber reaches an internal load state where polishing is possible, that is, the detected torque value reaches Toa, and initial polishing is started. When the detected torque value reaches Tab at time X3, the screw conveyor (6) is stopped for a predetermined time, the supply of brown rice is stopped, and the initial polishing continues with the discharge of polished rice also stopped. As the polishing process progresses, the bran is removed from the brown rice,
The detected torque value also gradually decreases. At time X4, main polishing is started, and a biasing force corresponding to the selected polishing mode is applied to the opening adjustment shaft (29), and the screw conveyor (6) is restarted. The torque value increases as brown rice is supplied to the milling chamber, and the opening adjustment shaft ( 29)
The whitening process is performed without controlling the biasing force against the grain. When the brown rice to be milled runs out, the detected torque value starts to decrease because no brown rice is supplied to the milling room.

At this point, that is, at point X5, the biasing force against the opening adjustment shaft (29) is increased to Pmax, and final polishing is performed while suppressing the discharge of polished rice from the discharge port. At the time when the brown rice in the milling chamber has been milled, that is, at the time of X6, the biasing force against the opening adjustment shaft (29) is lowered to P min to release the white rice from the milling chamber, and at the time of Xl, the milling process is completed. do.

The features of the control of the rice milling machine of the present invention described above are summarized as follows: 1. In the brown rice supply end determination step, if the detected value by the torque sensor is below a predetermined lower limit value, the brown rice Determine end of supply.

2. In the step of determining the end of supply of brown rice, if the value detected by the torque sensor exceeds a predetermined negative rate of change, it is determined that the supply of brown rice has ended.

3. In the step of supplying brown rice to the milling room, for the initial milling process, when the internal load of the milling room reaches a predetermined value, the supply of brown rice is temporarily stopped, milling is continued for a certain period of time, and then the supply of brown rice is stopped. resume.

4. After the step of determining the end of the supply of brown rice, as a terminal polishing process, the urging force is increased to temporarily suppress the release of white rice from the milling room, and then the urging force is decreased and the polishing is continued. A step of discharging the white rice from the chamber is performed.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

1 to 9 show an embodiment of the rice polishing machine according to the present invention, FIG. 1 is a longitudinal cross-sectional view showing the overall structure of the rice milling machine, and FIG. 2 shows a means for changing the biasing force of the opening regulating member. 3 is a control block diagram, FIGS. 4 to 8 are flowcharts showing the flow of control, and FIG. 9 is a graph showing the relationship between the polishing process and the value detected by the torque sensor. Further, FIG. 10 is a schematic diagram showing the configuration of a conventional rice milling machine.

Claims (1)

[Claims] 1. A rice milling machine consisting of the following configurations; (a) a milling chamber (3) equipped with milling rolls that polish brown rice into white rice; (b) brown rice that supplies brown rice to the milling chamber; Supply means (6)
, (c) polished rice outlet adjustment means (15, 19, 29, 35) provided in the polished rice outflow area of the whitening chamber; (d) a torque sensor (
25), (e) A control means (36) for controlling the polished rice outflow adjusting means according to a value detected by the torque sensor to maintain the internal load of the whitening room at a preset value. 2. The control means includes a torque value setting means for initial whitening process and a timer for initial whitening process, and when the whitening chamber is almost filled by the brown rice supply means, the value detected by the torque sensor is set for the initial whitening process. 2. The rice milling machine according to claim 1, wherein the brown rice supplying means is intermittently stopped or decelerated until the torque value is exceeded, and then polishing is performed with the supplying means stopped for a set time of the initial polishing processing timer. 3. The control means includes a terminal milling process determination unit that determines the end of the supply of brown rice to be milled when the detected value by the torque sensor indicates a predetermined internal load state of the milling chamber; When the processing determination unit determines that the supply of brown rice has ended, the polished rice discharge port adjustment means is configured to perform milling while temporarily suppressing the discharge of white rice from the milling chamber, and then discharge the polished rice from the milling chamber. Claim 1 to control
The rice milling machine described in . 4. The torque sensor (25) is connected to the whitening roll (11).
2. The rice milling machine according to claim 1, wherein the rice milling machine is configured to detect the torque of the rotating shaft of the rice milling machine. 5. A method for controlling a rice milling machine, in which when the internal load of a milling chamber equipped with a driven milling roll exceeds a biasing force preset by a biasing means, its discharge port is opened and polished brown rice is discharged; This method consists of the following steps: (1) selecting a degree of polishing; (2) supplying brown rice to the milling chamber; (3) setting a biasing force based on the selected degree of polishing; (4) detecting the internal load of the milling room with a torque sensor; (5) applying the energization based on the value detected by the torque sensor in order to maintain the internal load value set corresponding to the selected milling degree; (6) determining the end of supply of brown rice to be milled when the detected value by the torque sensor indicates a predetermined internal load state of the milling chamber;