JPH02310456A - Method for measuring moisture content of grain - Google Patents

Abstract

PURPOSE:To automatically select the dynamic range optimum for the grains to be measured and to allow the measurement of a prescribed number by determining plural sets of moisture content data for each of the respective dynamic ranges of the grains to be measured and comparing the adequate number of the moisture content data. CONSTITUTION:The specified number of the moisture contents are first measured in each of the set dynamic ranges in order to obtain the prescribed number of the moisture content data. The data inadequate for the measurement in the above-mentioned dynamic ranges and the data adequate therefore coexist in the measured results. The adequate number of the moisture content data of a specified number of the grains are then compared and the dynamic range where the adequate moisture content data is obtd. in the largest number is selected and switched; thereafter, the measurement is made in this selected dynamic range until the prescribed number of the moisture contents are obtd. The selected dynamic range has the high probability to measure the adequate moisture content data and, therefore, the prescribed number of the moisture content data are rapidly obtd.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention applies a voltage to crushed grains and measures the peak value of the voltage that changes depending on the electrical resistance of the grains. The present invention relates to a grain moisture content measurement method for calculating moisture content.

[Prior art]

Conventionally, grain moisture content measuring devices have been used to measure the moisture content of grains in order to ascertain the degree of dryness.

This grain moisture content measuring device is provided with a pair of rotating electrode rolls. The grains are fed between the electrode rolls and crushed. After that, a constant voltage is applied between a pair of electrode rolls, the voltage that changes depending on the electrical resistance of the crushed grains is measured, and the moisture content of the grains is calculated from this voltage.

By the way, the range of moisture content of grains is wide, and it is difficult to measure all grains in a single dynamic range.

That is, the resolution is poor when measuring grains with low moisture content over a wide dynamic range, and may exceed the maximum value when measuring grains with high moisture content over a narrow dynamic range. For this reason, two dynamic ranges, an L range and an H range, are usually switched depending on the grain to be measured. That is, for grains with low moisture content, two dynamic ranges, a narrow dynamic range (hereinafter referred to as L range) and a wide dynamic range (hereinafter referred to as H range), are switched depending on the moisture content of the grain to be measured. I have to. That is, by measuring grains with a low moisture content in the L range and switching to the H range with grains with a high moisture content, it is possible to measure the voltage near the peak with high reading accuracy.

[Problem to be solved by the invention]

However, when switching the dynamic range,
Since it takes a certain amount of time, when crushing multiple grains and measuring the moisture content multiple times, it is possible to select an appropriate dynamic range based on the initial measurement data. measurement), then
Measurement time is short and there is no room to choose the dynamic range.

Furthermore, if the dynamic range is switched every time, there is a problem that the durability of the relay that constitutes the switching mechanism is reduced.

The present invention takes the above facts into account and provides a grain moisture content measurement method that can automatically select the optimal dynamic range for the grain to be measured and quickly perform a predetermined number of grain moisture content measurements. That is the purpose.

[Means to solve the problem]

As shown in FIG. 1, the grain moisture content measurement method according to the present invention applies a voltage to crushed grains and measures the voltage value that changes depending on the electrical resistance of the grains by switching the dynamic range. This is a grain moisture content measurement method that obtains a predetermined number of grain moisture content data by obtaining a plurality of moisture content data for each dynamic range of the grain to be measured (step A), and determining the appropriateness of the moisture content data. The method is characterized in that the numbers are compared (Step B), and the predetermined number of moisture content data is obtained (Step D) in the dynamic range in which the most appropriate number of moisture content data is obtained (Step C).

[Effect]

In order to obtain a predetermined number of moisture content data, first, the moisture content of a certain number of grains is measured in each of the set dynamic ranges. In this case, the measured results include a mixture of data that is inappropriate and data that is appropriate when measured within that dynamic range.

Among these, the dynamic range in which the largest number of appropriate water content data was obtained is selected, and measurements are thereafter performed in this selected dynamic range until a predetermined number of water content data are obtained. Since the selected dynamic range has a high probability of measuring appropriate moisture content data, it is possible to quickly obtain a predetermined number of moisture content data.

Furthermore, since the dynamic range is not selected for each measurement, the durability of a mechanism for switching the dynamic range, such as a relay, can be improved.

〔Example〕

FIG. 2 shows a perspective view of a main part of a grain feeding device 10 according to an embodiment of the present invention and a moisture content measuring device 12 in which this grain feeding device 10 is used.

Moreover, a schematic sectional view of the grain feeding device 10 is shown in FIG.

The moisture content measuring device 12 is provided with a measuring section 14,
Further, inside the measuring section 14, a pair of electrode rolls 16 that rotate in opposite directions are arranged facing each other.

When grains are supplied between the electrode rolls 16 and the electrode rolls 16 are rotated, the grains can be crushed along with this rotation. Further, each electrode roll 16 is connected to a control unit 17, and the moisture content of the grain can be detected by passing current between both electrode rolls 16 and measuring the voltage between the electrode rolls 16 through the grain. It has become.

A grain feeding device 10 is arranged on the side of the measuring section 14. The grain feeding device 10 includes an endless annular belt 18. The belt 18 is wound around a pair of rollers 20.22, and the belt 18 (the pair of rollers 20.22) is arranged at an angle of inclination on the critical slip angle side of the grain. . In this embodiment, the positions of the rollers 20 and 22 are set so that the inclination angle is 45 degrees.

A motor 26 is connected to the roller 20 located at the lower side via a chain 24, and the belt 18 can be rotated by driving the motor 26.
8, the rollers 20, 22, and the motor 26 constitute a so-called belt conveyor that conveys the conveyed object upward (from the rollers 20 to the rollers 22).

In the belt 18, a plurality of through holes 28, 30, and 32, each serving as a conveyance hole, are formed on two sides in six width directions of the belt 18. Each through hole 28.30.32
They are formed at equal intervals along the longitudinal direction (rotational movement direction) of the belt 18 and over the entire circumference of the belt 18. Further, each through hole 28.30.3.2 is formed in an elliptical shape with a major axis along the longitudinal direction of the belt 18. Further, each through hole 28, 30, 32 is formed with a different size from each other, with through hole 28 having a large diameter and corresponding to large grains (e.g. barley), and through hole 30 having a medium diameter and corresponding to large grains (e.g. barley). The through hole 32 has a small diameter and a size corresponding to the shape of grains (for example, paddy or wheat), and the size and shape correspond to small grains (for example, brown rice or white rice).

A hopper 36 is provided directly above the belt 18 by a support plate 34.
is supported. The hopper 36 has a substantially cylindrical shape with both upper and lower ends open, and grains such as paddy, brown rice, white rice, wheat, or barley can be thrown into the hopper from the upper end opening. This hopper 36 has a lower end opening that is connected to the belt 18.
Hopper 3 is placed close to the
The grains introduced into the hopper 6 are prevented from falling from the lower end opening by the belt 18 and are held in the hopper 36.

The master hopper 36 is slidable along the support plate 34 in the width direction of the belt 18 (in the direction of arrow A in FIG. 2), so that the lower end opening of the hopper 36 is connected to each through hole 28 formed in the belt 18. 30.32. An opening/closing door 40 is attached with a hinge 38 near the opening at the lower end of the hopper 36, and the door 40 is used to open and close the grains introduced into the hopper 36 downward (i.e.,
(on the belt 18). A return spring 42 is attached to the hinge 38 so that the door 40 can always be opened and closed.
is biased toward the closed position.

Inside the endless ring on the opposite side of the belt 18 from the hopper 36,
A sorting plate 44 is arranged so as to be substantially in contact with the belt 18. The sorting plate 44 is provided with a through hole (not shown). Further, a saucer 52 is arranged directly below the sorting plate 44. Here, when the through hole and the through hole 28.30.32 are matched, if the size of the grain accommodated in the through hole 28.30.32 is smaller than the through hole, the grain is It passes through the through hole and is guided to the saucer 52.

One end of a pipe 54 is connected to the saucer 52,
Further, the other end of the pipe 54 is connected to a lees receiving box 56.

A guide plate 58 is arranged below the roller 20 located on the lower side. The upper end of the guide plate 58 is connected to the roller 20.
It corresponds to the belt 18 wrapped around the belt 18, and furthermore, the lower end is connected to the lees receiving box 56. Therefore, grains falling from the belt 18 can be guided to the lees receiving box 56.

The control unit 17 is provided with a range switch 62 to which a constant voltage is applied from a power supply device 60.

The range switch 62 is composed of a low-reswitch or the like, and has the role of changing the resistance value of the variable resistor 64. This range switcher 62 is controlled by a switching signal from a microcomputer 66, selects the dynamic range between the H range (switching signal H) and the L range (switching signal L), and sends a signal to the variable resistor 64. It is designed to be output.

The variable resistor 64 changes the resistance value according to the signal from the range switch 62 to change the voltage supplied to the electrode roll 16, so that an H range dynamic range circuit and an L range dynamic range circuit can be configured. It has become. Note that the H range is set to a dynamic range that is optimal when the moisture content of grains is high, and the L range is set to a dynamic range that is optimal when the moisture content of grains is low. This variable resistor 64 is connected to a microcomputer 66. Further, this variable resistor 64 also has the power supply device 6
A constant voltage is applied from 0.

The microcomputer 66 calculates the moisture content of the grain based on the measured voltage obtained from the electrical resistance of the grain, and displays the moisture content on the display 68.

The operation of this embodiment will be explained below.

First, the procedure for measuring the moisture content of grains will be explained.

In the moisture content measuring device 12 having the above configuration, when measuring the moisture content, grains for measurement are put into the hopper 36 and the grain feeding device 10 is driven.

When the grains are introduced into the hopper 36, the grains are held in the hopper 36 by the belt 18, which is disposed close to and directly below the opening at the lower end of the hopper 36. , 32), one grain at a time. Furthermore, the grains that have entered the through-hole 28 are held within the through-hole 28 by the sorting plate 44.

Next, when the motor 26 is driven and the belt 18 rotates, only the grains that have entered the through hole 28 out of the grains in the hopper 36 are removed because the belt 18 is inclined on the critical slip angle side. As the belt 18 moves, it is carried upward and moved toward the rollers 22.

Here, in the sorting plate 44 on the movement trajectory of the through-hole 28, a through-hole of a predetermined size smaller than the through-hole 28 is formed, so that among the grains that have entered the through-hole 28, more Even the smallest grains fall through the holes and are collected in the lees receiving box 56 via the receiving tray 52 and the vibrator 54. On the other hand, grains larger than the through-hole are held in the through-hole 28 without falling and are carried by the belt 18, and only these grains are transferred between the electrode rolls 16 of the measuring section 14 for measurement. Supplied individually as grains.

The grains supplied between the electrode rolls 16
The moisture content of the grains is detected by passing electricity between both electrode rolls 16 and measuring the electrical resistance of the current flowing between the electrode rolls 16 through the grains.

Next, the control for collecting 100 pieces of measured grain moisture content data will be explained according to the flowchart of FIG.

First, in step 100, variables 1 and K are set to 1, and variables J and L are set to 0.

In the next step 102, the dynamic range is set to the L range, and then in step 104, the voltage E between the electrode rolls 16 is measured in this range. Measured voltage E
is converted into a moisture content G by the microcomputer 34 (step 106), and the process moves to step 108.

In step 108, an inappropriate value for measurement in the L range (
G>18%), and if a negative determination is made, that is, it is determined that the value is appropriate for measurement in the L range, the process moves to step 110 and this converted moisture content G is determined. Assign to memory moisture content G□, then step 112
The variable I is incremented at step 114. If the determination in step 108 is affirmative, that is, the value is determined to be inappropriate for measurement in the L range, steps 110 and 112 are skipped and the process proceeds to step 114 without storing the converted moisture content G. Transition.

In step 114, a variable J indicating that the J-th measurement has been completed is incremented, and in step 116 it is determined whether this variable J has reached 50 times. here,
If it is determined that the number of measurements has not reached 50, the process moves from step 116 to step 104 and the above steps are repeated. If the number of measurements reaches 50 in step 116, the process moves to step 118, sets the dynamic range to the H range, and moves to step 12 (1-).

In step 120, the voltage E between the electrode rolls 16 is measured in this L range. The measured voltage E is converted into water content G by the microcomputer 66 (step 12).
1), proceed to step 122.

In step 122, a value that is inappropriate for measurement in the H range (
0518%), and if a negative determination is made, that is, it is determined that the value is appropriate for measurement in the H range, the process moves to step 123 and this converted moisture content G is stored in the memory moisture content. Then, in step 124, the variable K is incremented, and the process proceeds to step 125.

If it is determined in step 122 that the value is inappropriate for measurement in the H range,
Steps 123 and 124 are skipped and the process proceeds to step 125 without storing the converted moisture content G.

In step 125, a variable RI indicating that the L-th measurement has been completed is incremented, and in step 126 it is determined whether this variable RI has reached 50 times. here,
If it is determined that the number of measurements has not reached 50, the process moves from step 126 to step 120 and the above steps are repeated. Further, if the number of measurements reaches 50 in step 126, the process moves to step 128.

In step 128, the numerical values of variable I and variable I are compared. The variables correspond to the memory numbers of the measurement results of the L range and the H range, and it is determined which dynamic range will be applied from now on. That is,
It is determined that the one with the larger value for the variable work and the variable will finish the predetermined number of measurements (100 times in this example) more quickly, and the work ≧
If it is determined that this is the case, the process moves to step 130. In step 130, the dynamic range is set to L range, and the process moves to step 132, where the voltage E between the electrode rolls 16 is measured, and in step 134, the water content G is converted from this measured voltage E.

In the next step 136, the converted moisture content G is 18%.
If it is determined to be positive, it is determined that the value is inappropriate, and the converted moisture content G
is not memorized and the process moves to step 132. If a negative determination is made, it is determined that the measured moisture content G is appropriate, and the process proceeds to step 138 where the memory moisture content G is determined to be appropriate.
[Assign to This variable is a numerical value that is continuous to the variable I that corresponds to the memory moisture content G that was last stored in step 110.

In the next step 140, the variable ■ is incremented,
Next, in step 142, it is determined whether this variable I exceeds 100, and if the determination is negative, step 132
, and repeat the above steps. In addition, if a positive determination is made, it is determined that 100 measured values have been memorized,
This routine ends.

Next, in step 128, if it is determined that I is equal to K, the process moves to step 144. In step 144, the dynamic range is set to H range, and step 1
46, the voltage E between the electrode rolls 16 is measured, and in step 148, the water content G is converted from this measured voltage E.

In the next step 150, the converted moisture content G is 18%.
If it is determined to be positive, it is determined that the value is inappropriate, and the converted moisture content G
is not memorized and the process moves to step 146. If a negative determination is made, it is determined that the measured moisture content G is appropriate, and the process proceeds to step 152 where the memory moisture content G is determined to be appropriate.
K". This variable has the value specified in step 123 above.
This is a numerical value that is continuous to the variable K corresponding to the memory moisture content GK' stored last.

In the next step 154, the variable K is incremented,
Next, in step 156, it is determined whether this variable K exceeds 100, and if the determination is negative, step 146
, and repeat the above steps. In addition, if a positive determination is made, it is determined that 100 measured values have been memorized,
This routine ends.

In this way, in this example, measurements are made 50 times in each of the two types of dynamic ranges, only the appropriate data is stored, and the dynamic range with the largest number of stored data is applied. , the remaining data is a predetermined number (100
), it is possible to quickly and appropriately obtain a predetermined number of data.

In addition, in this example, the dynamic range is L range and H range.
Although we have set two types of dynamic ranges, three or more types of dynamic ranges may be set. In this case, the moisture content of a certain number of grains is measured in each dynamic range, and the dynamic range with the largest number of appropriate data is selected. Just apply it.

In addition, in this example, the appropriate moisture content measured in the dynamic range that was not applied was not adopted as the predetermined number of data, but even if both the moisture content data G□ and G, + are applied as data. good.

〔Effect of the invention〕

As explained above, the method for measuring grain moisture content according to the present invention includes:
It has the excellent effect of automatically selecting the optimum dynamic range for the grain to be measured and quickly measuring the moisture content of a predetermined number of grains.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to the claims, Fig. 2 is a perspective view of a moisture content measuring device according to an embodiment of the present invention, Fig. 3 is a schematic sectional view of a grain feeding device, and Fig. 4 is a diagram according to the present embodiment. It is a control flowchart. 12... Moisture content measuring device, 16... Electrode roll, 62... Range switch, 64... Variable resistor, 66... Microcomputer. Figure 1 Figure 2 Figure 3 Figure 1

Claims (1)

[Claims] (1) Grain moisture content that obtains a predetermined number of grain moisture content data by applying a voltage to crushed grains and measuring the voltage value that changes depending on the electrical resistance of the grain by switching the dynamic range. The measurement method is to obtain a plurality of moisture content data for each dynamic range of the grain to be measured, compare the appropriate number of moisture content data, and calculate the optimum number of moisture content data in the dynamic range in which the optimum number of moisture content data is obtained. A grain moisture content measuring method characterized by obtaining the predetermined number of moisture content data.