JPH0119937B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a rice milling machine that automatically mills rice efficiently and without impairing the quality of polished rice.

Conventional technology Figure 5 shows the configuration of a conventionally used circulating rice mill.
Grains such as brown rice are forcibly circulated through a belt 4 by a polishing roll 3 driven by a rice polishing motor 5 as shown by the arrow.

At this time, rice is polished by the friction between the polishing roll 3 and the grains, and the resistor 6a acts as a circulating load on the grains, and by operating the manual knob 9, the magnitude of the amount of movement l can be changed. , the whitening power of the vertical whitening chamber 2b is changed.

At this time, if the protruding amount l of the resistor 6a is small, the circulation load on the grains is small, and the grains passing through the vertical milling chamber 2b and milling roll chamber 2a in the milling chamber 2 provided in the grain passage. The applied pressure is small;
Therefore, the whitening power is also small.

Conversely, when the protrusion amount l of the resistor 6a is large, the circulation load on the grain is large, the pressure applied to the grain passing through the whitening roll chamber 2a and the vertical whitening chamber 2b is large, and the whitening force is also large.

Problems to be Solved by the Invention Figure 6 shows the change in pressure applied to grains in the milling roll chamber 2a as milling time elapses in a conventional circulating rice mill. If the protrusion amount l of the resistor 6a is initially set to 10 mm and is adjusted twice to 20 mm and 25 mm during rice polishing, the curve b becomes
When fixed at 17.5 mm, curve c is a curve showing the pressure change of each model a, b, and c when fixed at 30 mm.

In this figure, curve b is a case in which the protrusion amount l of the resistor 6a is made larger than in the case of curve a, and the protrusion amount is not adjusted during the process.In the early stage of rice milling, the pressure applied to the grains is large, that is, the grain The circulation load is large, and an unreasonable load is placed on the rice polishing motor 5, and the milling time is required to be longer than that of curve a.

(b) Curve c is a case where the protrusion amount of the resistor 6a is significantly increased and no adjustment is made midway; in this case, abnormal pressure is applied to the grains and the incidence of broken rice is high;
In addition, a significantly excessive load is applied to the rice milling motor, making it impossible to perform normal rice milling operations.

C. Curve a is the standard method for model a, excluding the shortcomings of model curves b and c above, and is a method of stabilizing by adjusting the protrusion amount l of the resistor 6a twice during rice milling, which is ideal. Although it is possible to mill rice, it has the following problems.

In order to correct the polishing power that decreases with time, the resistor 6a is manually pressed several times during rice polishing.
It is necessary to adjust the protrusion amount l, and hand-held (unmanned) operation is not possible.

Since the protrusion amount l of the resistor 6a is determined by human experience and intuition, it is difficult to determine the correct position, and in some cases, the rice polishing motor 5 may be overloaded.
There is a risk of burnout.

When rice is directly milled from paddy, the pressure change applied to the paddy is larger than when milling from brown rice, and adjustment of the resistor 6a during rice milling becomes more troublesome.

When the grain material changes, the hardness of the grains differs due to differences in variety, moisture content, etc., so it is necessary to adjust the protrusion amount 1 of the resistor 6a for each milled rice using experience and intuition.

The purpose of this invention is to solve the above problems and make it possible to automatically adjust rice milling within a certain pressure range to accommodate differences in hardness due to differences in grain type, variety, and moisture content. It is something.

Means for Solving the Problems The structure of the present invention will be explained with reference to the attached drawings (FIGS. 1 to 3) of one embodiment. The wall surface 13 of the vertical milling chamber 2b of a part of the milling chamber 2 located in the grain passage. In this rice milling machine, a strain sensor 7 is provided on the wall surface 13 of the vertical polishing chamber 2b, and the strain sensor 7 and the resistor 6 Voltage conversion amplifier 1
4. This rice milling machine is constructed by sequentially connecting a control circuit 8 which is formed by sequentially connecting a comparison circuit 15 and a drive circuit 16, and a motor 11 for adjusting the position of the resistor 6.

Operation With the above configuration, when the wall surface 13 expands and contracts due to the pressure of the grains passing through the vertical milling chamber 2b, the value is detected by the strain sensor 7 and converted into an electric signal, and various types of the control circuit 8 are The circuit is activated, and the position adjustment motor 11 is rotated forward or reverse, or stopped according to its output signal.

By forward rotation of the position adjustment motor 11, the resistor 6 protrudes into the vertical polishing chamber 2b, and by reverse rotation, it returns to its original position. Therefore, by adjusting the operation of the control circuit 8 in advance according to the type of grain, the amount of protrusion l of the resistor 6 can be adjusted according to the change in pressure on the grain passing through the vertical milling chamber 2b. By holding it in the proper position, the pressure applied to the grain can always be maintained within the proper range.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 4 of the accompanying drawings. The whitening chamber 2 is a whitening roll chamber 2a.
and a vertical whitening room 2b. A strain sensor 7 is provided on the outer wall surface 13 of this vertical milling chamber 2b, and a resistor 6 is attached to the wall surface at a position opposite to the wall surface 13 across the grain circulation path, the configuration of which is shown in FIG. There is a rotation stop protrusion 12 in the center like this.
and is directly connected to a position adjustment motor 11 via a coupling ring 10.

Although not shown in FIG. 1, the above-mentioned strain sensor 7 and position adjustment motor (hereinafter abbreviated as motor) are also included.
A control circuit 8 that controls the amount of protrusion of the resistor 6 is connected between the resistor 11 and the resistor 11 .

As shown in the block diagram of FIG. 3, one embodiment of the control circuit 8 includes a voltage conversion amplifier circuit 14 that amplifies the electrical output signal from the strain sensor 7 and sends it to the next stage. A comparison circuit 15 receives the signal voltage, compares it with a set reference voltage value, and controls a signal sent to the next stage drive circuit 16, and a position adjustment motor 11 receives an output signal from the comparison circuit 15. Drive circuit 1 that controls the drive of
It consists of 6.

FIG. 4 shows the elapsed operating time of the rice milling machine of the present invention and the change in pressure applied to the grains, and shows dial x,
The curve of the dial y is a pressure change curve when the positions of the knobs of the reference voltage adjustment dial (not shown) of the comparison circuit 15 are respectively x and y.

With the above configuration, when the adjustment dial is set to the x position and rice milling is started, the pressure applied to the grains passing through the circulation passage changes as time elapses, causing the wall surface 13 to expand and contract. This state of change is detected by a strain sensor (strain gauge) 7 provided on the wall surface 13 of the vertical whitening chamber 2b, converted into an electrical signal, and sent to the voltage conversion amplifier circuit 14. The voltage conversion amplifier circuit 14 receives the output signal, amplifies the voltage, and sends it to the comparison circuit 15 at the next stage.

As time passes, the pressure applied to the grain decreases and when it reaches level L ₁ in FIG. , the comparison circuit 15 functions and sends a signal to the next-stage drive circuit 16. The drive circuit 16 receives this signal and sends a signal to the motor 11 to rotate the motor 11 in the forward direction.

When the motor 11 rotates in the forward direction, the amount l of the resistor 6 protruding into the vertical milling chamber 2b increases, and the pressure applied to the grains increases and reaches the _L2 level. At this time, the output signal from the strain sensor 7 also increases and the comparison circuit 15
The input voltage to the comparator circuit 15 also increases, and when this reaches the upper limit of the reference voltage range, the output signal of the comparator circuit 15 stops.
Since the signal transmission from the drive circuit also stops, the operation of the motor 11 also stops, and therefore the protrusion of the resistor 6 also stops.
Stop at that position.

If the grain is particularly soft and the pressure inside the vertical milling chamber 2b exceeds level _L2 , the motor 11 is reversely rotated by the output signals of the comparator circuit 15 and the drive circuit 16 to reduce the amount of protrusion of the resistor 6. reduce When the whitening pressure reaches _L2 , the output of the comparator circuit 15 disappears, and the motor 11 also stops rotating.

By repeating this cycle, rice milling can be automatically performed within the pressure range most suitable for grains from the start to the completion of milling.

When the knob of the adjustment dial is in the y position, resistor 6
It is used when the protrusion amount l is smaller than when x, the milling pressure is lower overall, and the grains are soft.

The above embodiments have described a circulation type rice milling machine, but even in a one-time rice milling machine, a strain sensor is provided on the outer wall of the milling chamber, and the strain sensor is connected to a resistance plate at the milling chamber outlet via a control circuit. With this, it is possible to obtain the same effect as the circulation type.

Effects of the Invention The present invention has the above-mentioned structure, and in particular, a strain sensor is provided on the wall of the milling chamber, and the strain sensor is connected to the motor for adjusting the position of the resistor through a control circuit, so that the milling pressure can control the expansion and contraction of the wall. The amount of movement of the resistor can be freely controlled by driving a motor for adjusting the position of the resistor through a control circuit based on the measured value.

Therefore, it is possible to automatically adjust the polishing pressure within a certain range that is suitable for the hardness of the grains, which allows unattended rice milling work to be carried out efficiently, and because abnormally high pressure is not applied to the grains. You can always get high quality white rice. In addition, if the strain sensor is provided on the outer wall of the milling room, the installation is easy and the flow of grains is not adversely affected.

[Brief explanation of drawings]

FIG. 1 is a front longitudinal sectional view of an embodiment of the present invention, and FIG.
The figure is an enlarged sectional view of the main part of FIG. Figure 3 is a block wiring diagram of the control circuit connected between the strain sensor and the resistor, Figure 4 is a diagram of changes in pressure applied to grains in the milling chamber, and Figures 5 and 6 are conventional examples. 5 is a front vertical sectional view of the rice milling machine, and FIG. 6 is a diagram showing changes in pressure applied to grains when the amount of protrusion of the resistor is changed. 2... Refining room, 6... Resistor, 7... Strain sensor, 8...
control circuit.

Claims (1)

[Scope of Claims] 1. In a rice milling machine in which a resistor 6 for adjusting the milling force is movably provided in the grain passage, a strain sensor 7 is provided on the wall of the milling chamber 2, and the grain passing through the milling chamber 2 is Detecting changes in pressure on the grains by the strain sensor 7,
A rice milling machine characterized by being provided with means for automatically controlling the movement of a resistor 6 via a control circuit 8. 2. The control circuit 8 is provided between the strain sensor 7 and the position adjustment motor 11 for moving the resistor 6, and is configured by sequentially connecting a voltage conversion amplifier 14, a comparison circuit 15, and a drive circuit 16. A rice milling machine according to claim 1.