JPH0249652B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an improvement of a moisture content measuring device, and particularly to a moisture content measuring device that automates grain type discrimination that can discriminate the type of grain.

[Conventional technology]

Generally, in a moisture content measuring device that crushes and clamps a sample grain between a pair of electrodes and detects the electrical resistance value generated between the electrodes to measure the moisture value of multiple types of grain, the electrical resistance value and the moisture value are The correlation with grains differs depending on the type of grain and is not the same.

For this reason, conventionally, in order to be able to measure different types of grains with the same device, resistance type moisture meters have required hardware processing or software processing. As shown in FIG. 8, the hardware processing uses a selection switch 50 placed on the operating surface of the moisture meter to switch the circuit blocking of the measuring circuit according to the type of grain. In other words, the resistor Ra with the sample inserted in series,
Resistor Rb inserted in series with the diode of the feedback circuit
The linearization circuit is switched to obtain a moisture value suitable for each type of grain. On the other hand, in software processing, the grain type data set by the selection switch is read into a microcomputer, etc., without changing the moisture measurement circuit, and the grain type data is converted to the grain type using a pre-stored conversion formula or conversion table. It is converted to the corresponding moisture value.

[Problem that the invention seeks to solve]

However, with a moisture meter, the operation for selecting grains is manual and requires human intervention, so there is always the possibility of erroneous operation. If there is an error in grain selection, the moisture value of a different type of grain will be displayed.
In particular, automatic moisture meters attached to grain dryers tend to cause over-drying or under-drying, and as a result, grains cannot be dried to the optimum condition depending on the type of grain.

[Purpose of the invention]

Therefore, the purpose of this invention is to eliminate the above-mentioned drawbacks, and to automate the switching operation of the equipment according to the type of grain when measuring the moisture value of different types of grains using the same equipment, thereby eliminating the erroneous operation caused by manual switching operation. The object of the present invention is to realize a moisture content measuring device that can measure moisture content.

[Means for solving problems]

In order to achieve this objective, the present invention is a moisture content measurement method that measures the moisture content of multiple types of grain by crushing and sandwiching a sample grain between a pair of electrodes and detecting the electrical resistance value generated between the electrodes. The device includes a measurement circuit unit that measures the change in the electrical resistance value, a load sensor unit that measures the load applied to the sample grain between both electrodes, and an electrical An A/D conversion means for converting into digital measurement data, a storage unit storing a relationship table of measurement data between moisture and load for each type of sample grain determined in advance, and The type of sample grain is automatically determined by matching the input measurement data of moisture and load with the relation table in the storage unit, and the moisture measurement data is converted into a moisture value according to the determined type of grain. and an arithmetic processing unit that outputs the result.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

In FIGS. 1 to 4, reference numeral 2 denotes a measuring section that crushes and clamps the sample and measures the water content based on the electrical resistance value. It consists of lower electrode parts 6 arranged oppositely.

1 and 2 show a first embodiment of the measuring section 2, in which the upper electrode section 4 includes a hollow cylindrical exterior section 8 and an interior section screwed into the hollow section of the exterior section 8. Consists of 10. Concave grooves are formed on the left and right side surfaces of the upper end of the exterior part 8, and the tips of the crush springs 12 are respectively inserted into the concave grooves, so that the upper electrode part 4 is moved up and down by both the crush springs 12. hold possible. For this reason, the upper surfaces of the other ends of both of the crush springs 12 are pressed against the upper surfaces of the left and right side walls 14-1 by the spring pressers 16. And these two crush springs 1
Strain gauge 1 on either upper and lower surfaces A of 2
8 is attached, and the load acting on the sample subjected to crushing strength between the upper and lower electrode parts 4 and 6 is detected by the displacement generated in the crushing spring 12 that holds the upper electrode part 4. Note that the strain gade 18 may be of any type as long as it can detect the load acting on the sample, so the mounting location is not necessarily limited to the above-mentioned positions, and may be, for example, positions B and C. On the other hand, the interior portion 10 can move up and down in a spiral manner by a driving force from a driving source (not shown). Further, a circular portion 4a is formed on the lower surface of the interior portion 10 by projecting downward from the center of the lower surface through a small circular portion in a stepped manner.

The lower electrode part 6 directly carries a sample extracted from inside the dryer (not shown), and also the upper electrode part 4
Together with this, it constitutes a pair of electrode portions which will be described later. In addition, by protruding the circular outer peripheral edge of the lower electrode part 6 and surrounding the central part 6a, the lower electrode part 6 with the sample placed on the central part 6a is located at a position facing the upper electrode part 4 in the vertical direction. This serves to prevent the sample from deviating from the lower electrode section 6 while the sample reaches the lower electrode section 6.

FIG. 3 shows a second embodiment of the measuring section 2.
The exterior portion 8 of the upper electrode portion 4 is directly supported by side walls 14-2 protruding from the left and right sides. In addition, the lower electrode part 6 is directly supported by the mounting table 20, and
The other ends of the two plate-shaped elastic members 22-1, which directly support the mounting table 20 with their upwardly bent ends, are attached to the lower surfaces of the left and right side walls 14-2 using tightening tools, respectively. The strain gauge 18 is attached to the upper and lower surfaces A of either one of the elastic members 22-1. This attachment point does not need to be on the elastic member 22-1, and may be at position B, for example, as in the case of the first embodiment. Configurations other than the above are the first
The configuration is the same as in the embodiment.

FIG. 4 shows a third embodiment, in which the upper electrode section 4 is supported in the same manner as in the second embodiment, but the lower electrode section 6 is supported by a mounting table 20 that supports the lower electrode section 6. A plate-shaped elastic member 22-2 is interposed between the mounting table 20 and a support table 24 that supports the mounting table 20 from below. The strain gauge 18 is the elastic member 2
Although it is attached to position A in 2-2, it is not limited to this position as described above, and may be installed at position B, for example. The point is that the position may be any position as long as it can detect the load acting on the sample held between the upper and lower electrode parts 4 and 6. Note that both ends of the support stand 24 are attached to the lower surfaces of the both side walls 14-2 using fasteners. The configuration other than the above is the same as in the first embodiment.

FIG. 5 is a circuit diagram showing the control mechanism of this invention.
Reference numeral 26 denotes a pair of electrodes for crushing and clamping a sample and detecting the electrical resistance value there between. 28 is the above pair of electrodes 26
This is a conversion/amplification circuit that amplifies and converts the electrical resistance value generated between them into a voltage signal, and constitutes a measurement circuit section together with the measurement section 4. 42 is the strain gauge 1 already mentioned.
8 constitutes a bridge, and a diffusion type semiconductor type strain gauge 18 constitutes a full bridge system.When no pressure is applied, the four pressure-sensitive resistors are equal, but when pressure is applied, the resistance balance of the bridge changes. As a result, the input voltage of the differential amplifier increases in proportion to the applied pressure, and the pressure can be detected. It goes without saying that the strain gauge 18 is not limited to the diffused semiconductor type, and the structure of the bridge is not limited to the full bridge type, but may also be configured such that the strain gauge 18 is inserted on one or two sides of the bridge. 30 is an amplifier that amplifies the voltage generated in the load sensor 42, 32 is a multiplexer that commonly transmits voltage signals sent separately from the conversion amplifier circuit 28 and the amplifier 30 by a method such as time division, and 34 is the multiplexer 32. This is an A/D conversion circuit that inputs the voltage as an analog quantity sent from the computer and converts it into a digital signal. 36 is a microcontroller consisting of a part that performs calculations and controls based on digital signals sent from the A/D conversion circuit, and a main memory device.
A computer (CPU) 38 is a read-only memory (ROM) that stores a control program in advance and supplies data to the CPU 36. Reference numeral 40 denotes a readable and writable data random access memory (RAM) consisting of a plurality of storage areas for temporarily storing calculation results of the CPU 36, input data, etc. 41 is the above
It is an arithmetic processing unit consisting of a CPU 36, a ROM 38, and a RAM 40, and is a device (not shown) that automatically determines the type of grain and converts moisture measurement data into a moisture value corresponding to the identified grain and outputs it. It has a function to automate switching operations. 44 is a display that simultaneously displays the type of grain and the measured moisture value, and the type of grain is A (rice), B (wheat), and C (barley).
It consists of display sections 44a, 44b, and 44c that display the water content, and a display section 44d that displays the moisture value. 46 is a display drive circuit for displaying the moisture value data output from the arithmetic processing section 41 on the display 44. The automatic moisture meter reads the moisture value data processed by the arithmetic processing section 41 as information for controlling the grain dryer.

In FIG. 5, W and M indicate the transmission paths of the measured load measurement data W and the moisture measurement data M, respectively.

FIG. 6 shows a flowchart of the control kiln program. This control program is the ROM mentioned above.
The measuring section 2 and the control mechanism, particularly its input section and output section, are controlled by the control program and perform a series of operations.

Since the present invention is constructed as described above, it operates as follows.

First, sample grain to be measured is extracted from inside a grain dryer (not shown), introduced into the center part 6a of the lower electrode part 6, transferred into the measurement part 2, and then transferred to the measurement part 2.
The upper electrode section 4 is set in a position vertically facing the inner upper electrode section 4. Next, the inner part 10 of the upper electrode part 4 is caused to spirally move by a driving force from a drive source (not shown), and the inner part 10 is lowered. Interior part 10 that descended
The circular portion 4a formed on the lower surface of the sample contacts the sample placed on the lower electrode portion 6 and at the same time presses the sample to apply a load. At this time, the upper and lower electrode parts 4 and 6 receive a reaction force equal to the load applied to the sample. In this case, in the first embodiment, the upper electrode part 4 is only held by the crushing spring 12, so when it receives a reaction, it is displaced upward, and the crushing spring 1 holding the upper electrode part 4
2 also bends upward, the upper surface side of the crush spring 12 contracts, and the lower surface side expands. This is detected by a strain gauge 18 attached to the crush spring 12. At this time, the load W applied to the sample has the relationship W=K·d1+d2. here,
K is the elastic constant of the crush spring, d1 is the distance between the upper and lower electrode parts, and d2 is a constant. In addition,
Since the lower electrode section 6 is placed on the rigid bottom of the measurement section 2, displacement in the vertical direction is restrained. On the other hand, in the second and third embodiments, the upper electrode section 4 is restrained from vertical displacement by the side walls 14-2, so that only the lower electrode section 6 is displaced downward when subjected to a reaction. In the second embodiment, the elastic member 22-1 supporting the lower electrode part 6 is bent downward,
The upper surface side of the elastic member 22-1 extends, and the lower surface side contracts. Strain gauge 18 with this installed on both the upper and lower sides
Detected by. In the third embodiment, the plate-shaped elastic member 22-2 is compressed, and the amount of compression is detected by the strain gauge 18. Although not mentioned in the examples, there is also a method of measuring the distance d1 between the upper and lower electrodes in the above equation with a displacement sensor or the like, and using the above equation to determine the load applied to the sample.

The measured value of the load detected by the load sensor 42 composed of these strain gauges 18 is converted into voltage and sent to the multiplexer 3 via the amplifier 30.
Sent to 2. On the other hand, the moisture value of the sample measured by the upper and lower electrode sections 4 and 6 is converted into a voltage by the conversion amplifier circuit 28 and sent to the multiplexer 32. Therefore, both of the above signals are A/D converted by the A/D conversion circuit 34 according to a control signal from the CPU 36.
Send to CPU36. When the load sensor section uses both displacement sensors, the displacement amount signal sent in is converted using the above formula before performing the following processing. The CPU 36 processes it according to the flowchart shown in FIG. That is, the CPU 36 performs the following processing. First, the A/D conversion circuit 34
Moisture and load measurement data M, W sent from
Enter. Next, the grains A, B, D, . . . corresponding to the input moisture measurement data M, and the load measurement data Wa, Wb, Wc, . . . for each type are read out from the attached table. Next, the measured data W of the load is compared with each load Wa, Wb, Wc, . . . . For example, if W=Wa, the moisture measurement data M is converted into the moisture value Ma of grain A. This is because, as already mentioned, the moisture measurement data M and the actual moisture value differ depending on the type of grain. Through the above series of arithmetic operations, a result is obtained that the sample to be measured is grain A and its moisture value is Ma.
Finally, the grain type A and the moisture value Ma are displayed on the display windows 44a and 44d, respectively, and in the automatic moisture meter, the grain dryer is controlled.

Here, the above-mentioned table in the attached sheet will be explained using FIG. 7. FIG. 7 shows the relationship between the moisture measurement data M and the load measurement data W of the grain to be measured. It was discovered that when a certain grain A is measured with an electrical resistance moisture meter, there is a one-to-one relationship between the moisture measurement data M and the load applied to the sample. This is because the hardness of the grain is determined by the moisture content. When measuring with a moisture meter composed of the pair of electrode sections 26 described above, grains with lower moisture content have higher hardness and are more difficult to crush. Therefore, the distance between the upper and lower electrodes during clamping increases, and the load applied to the sample to be measured increases. Figure 7 is a graph of this. Furthermore, since the slope differs depending on the spring constant of the spring supporting the electrode, it is necessary to experimentally determine the relationship. As a way to memorize this relationship, the attached table is a graphical version of Figure 7, and for comparison with the actually measured load data W, grain load measurement data W _A corresponding to the moisture measurement data M is shown. , W _B , and W _C are read from this table. However, although the above description uses a table, there is also a method of storing the relational expression and calculating it each time a measurement is made.

Note that the present invention is not limited to the above-described embodiments, and various modifications can be made.

For example, in the embodiment of the present invention, as is clear from the drawings, the upper electrode part and the lower electrode part, which are a pair of electrodes, are formed into a flat plate shape. It is also possible to form both electrode portions into a roll structure or other known structure.

〔Effect of the invention〕

As is clear from the above description, according to the configuration of the present invention, the type of grain can be determined by measuring the load applied to the grain and the moisture value of the grain at that time. When measuring the moisture value of grain using the same device or controlling the drying of grain using the measured value, it is possible to automatically switch the device according to the type of grain. . Therefore, there is no need to manually switch the type of grain as in the past, and there is no possibility of erroneous operation. Since the manual moisture meter automatically displays the type of grain and moisture value measured, the operator can perform subsequent grain drying operations without error based on the display. In addition, an automatic moisture meter can obtain the type and moisture value of the measured grain, and these values can be used to accurately control the grain dryer. As a result, it is possible to reliably obtain grains that have been dried in an optimal state according to the type of grains, so that extremely novel and beneficial effects can be achieved.

[Brief explanation of drawings]

Figures 1 to 7 show embodiments of the moisture content measuring device that automates grain type discrimination according to the present invention.
The figure is a side view of the measuring section of the first embodiment, and the second figure is a side view of the measuring section of the first embodiment.
Figure 3 is a side view of the measuring section of the second embodiment, Figure 4 is a side view of the measuring section of the third embodiment, and Figure 5 is a side view of the measuring section of the third embodiment.
The figure is a circuit diagram of the control mechanism, FIG. 6 is a flowchart, and FIG. 7 is a graph showing the relationship between moisture measurement data M and load measurement data W of each grain. FIG. 8 is an explanatory diagram of the conventional technology. In the figure, 2 is a measurement part, 4 is an upper electrode part, 6 is a lower electrode part, 8 is an exterior part, 10 is an interior part, 12 is a crush spring, 14 is a side wall, 16 is a spring retainer, and 18 is a strain gauge. , 20 is a mounting table,
22 is an elastic member, 24 is a support base, 26 is a pair of electrode parts, 28 is a conversion amplifier circuit, 30 is an amplifier, 32
is a multiplexer, 34 is an A/D conversion circuit, 36
38 is a read-on memory (ROM), 40 is a random access memory (RAM), 42 is a load sensor, 44 is a display device, 4
4a, 44b, 44c, . . . are display windows, 46 is a display drive circuit, and 50 is a selection switch.

【table】

Claims (1)

[Claims] 1 In a moisture content measuring device that crushes and clamps a sample grain between a pair of electrodes and measures the moisture value of multiple types of grain by detecting the electrical resistance value generated between the electrodes, changes in the electrical resistance value are measured. A measuring circuit section for measuring, a load sensor section for measuring the load applied to the sample grain between both electrodes, and an A/R for receiving the outputs of the measuring circuit section and the load sensor section and converting them into measurement data of electrical digital quantities. A D conversion means, a storage unit that stores a relationship table of measurement data between moisture and load for each type of sample grain determined in advance, and a storage unit that stores measurement data of moisture and load input from the A/D conversion means. It is equipped with an arithmetic processing unit that automatically determines the type of sample grain in correspondence with the relational table in the storage unit, and converts the moisture measurement data into a moisture value corresponding to the determined type of grain and outputs it. A moisture content measuring device that automates grain type discrimination.