JPS6151258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrical resistance grain moisture meter, and more particularly to a method for measuring inter-electrode pressure of an electrical resistance grain moisture meter.

Electrical resistance grain moisture meters utilize the correlation between the electrical resistance of grains and the moisture content. It is indispensable for monitoring and inspection, and is now used by each farmer.

The electrical resistance type grain moisture meter measures the resistance value of a predetermined amount of grain between electrodes under a predetermined voltage, but the following conditions must be satisfied for this measurement. That is, (1) the amount of grain to be measured (hereinafter referred to as sample amount) is a predetermined amount, (2) the spacing between the electrodes is constant, and (3) a predetermined pressure is applied to the grain to be measured between the electrodes. (4) The voltage applied between the electrodes must be constant.

The above conditions are set individually for each type of electrical resistance grain moisture meter to suit the method of drying grains at 105°C for 5 hours. The above-mentioned problem (1) regarding the amount of sample is a measurement problem, and the sample can be taken using a specified method using a specified spoon, etc., and is not a severe problem unique to electric resistance grain moisture meters. Furthermore, the voltage problem (4) is a problem specific to electrical resistance grain moisture meters, but to determine whether a constant predetermined voltage is always occurring, it is necessary to connect an equivalent resistance between the electrodes and measure the voltage (i.e., to measure the voltage). It is relatively easy to display the moisture percentage corresponding to the equivalent resistance on the indicator, so it is not a serious problem.

However, the problems of (2) the spacing between the electrodes and (3) the predetermined pressure are serious problems because the mechanical structure of electrical resistance grain moisture meters inevitably changes over time. Furthermore, the electrode spacing and the predetermined pressure have a causal relationship with each other, that is, when the predetermined pressure is applied to the grain, the inter-electrode spacing must reach a predetermined value.

The electrode of an electric resistance grain moisture meter consists of a pressure electrode that presses a predetermined sample amount of grain and a counter electrode supported by an elastic member such as a spring. The elastic force of the elastic member is adjusted so that a predetermined distance between the electrodes is obtained at a predetermined pressure when the electrode is fully operated until it collides with a stopper provided on the main body.

The above elastic force tends to decrease when frequent measurements are repeated, and therefore the predetermined pressure decreases.

For this reason, to adjust the spacing between the electrodes and the elastic force of an electrical resistance grain moisture meter, insert a pressure detection sensor between the electrodes, operate the pressurizing electrode at full force, and then measure the pressure with the pressure detection sensor. , adjusting the elastic force of the elastic member.

Japanese Unexamined Patent Publication No. 104399/1983 discloses an electrode adjustment method and a pressure detection sensor for an electrical resistance grain moisture meter. This pressure detection sensor has a pressure detection end that includes a strain gauge, and pressure is measured by sandwiching this pressure detection end between electrodes. Since this pressure detection end has the same thickness as the predetermined electrode spacing, the pressure detection end is inserted between the electrodes, the pressurizing electrode is fully operated, and the pressure is monitored with the pressure detection sensor. If a predetermined pressure is obtained by adjusting the elastic force of the elastic member, the electrode can be easily adjusted.

However, although the above-mentioned known pressure detection sensors are convenient, they are expensive and are not suitable for use by manufacturers or service centers of electrical resistance grain moisture meters to adjust the electrodes of a large number of electrical resistance grain moisture meters. However, it is uneconomical and therefore unsuitable for use as a pressure detection sensor owned and used by each farmer who actually uses the electric resistance grain moisture meter.

The above-mentioned elastic member is a part of the mechanical structure of the electrical resistance grain moisture meter that is likely to change over time, and therefore requires periodic adjustment of its elastic force. Adjusting the elastic force itself is relatively easy and does not require special technology, but since the pressure detection sensor mentioned above is required, the electric resistance grain moisture meter must be sent to the manufacturer or service center for adjustment. It is inconvenient.

The present invention provides an electrode adjustment method for an electrical resistance grain moisture meter that eliminates the above drawbacks.

In recent years, pressure measuring films for pressure measurement have been sold. For example, Fuji Photo Film Co., Ltd. sells a pressure sensitive film for pressure measurement (hereinafter simply referred to as "pressure sensitive film") under the trade name Prescale. This pressure measurement film is designed to produce different colors depending on the magnitude of the pressure generated.For example, in the Prescale mentioned above, the color is colored differently depending on the magnitude of the pressure. It's summery. It is theoretically possible to obtain a pressure measurement film that develops different colors depending on the magnitude of pressure.

The method of the present invention uses the pressure measuring film described above to adjust the electrodes of an electrical resistance grain moisture meter.

According to the present invention, the steps include arranging a pressure measurement film on a substrate made of a hard material, sandwiching the portion of the substrate on which the pressure measurement film is arranged between electrodes of an electrical resistance grain moisture meter, and arranging the substrate on a substrate made of a hard material. An electric resistance type grain moisture meter comprising the steps of taking out the pressure measurement film and observing the color development state of the pressure measurement film, and adjusting the elastic force of the elastic member of the electric resistance type grain moisture meter that acts between the electrodes from the color development state of the pressure measurement film. A method for adjusting pressure between electrodes of a meter is provided.

Another object of the present invention is to provide a pressure-sensitive gauge for measuring pressure between electrodes of an electrical resistance grain moisture meter using a pressure-measuring film.

Hereinafter, the present invention will be explained in detail in the form of an embodiment and with reference to the accompanying drawings.

FIG. 1 is a partially cutaway view showing the electrode portion of a conventionally known electrical resistance moisture meter, where reference number 1 indicates a screw member constituting the upper electrode, and reference number 2 indicates the lower electrode. The screw member 1 is screwed into an insert 5 provided in the upper opening of the main body 4, and a handle 9 is integrally provided at the top of the insert 5. The lower electrode 2 is supported on its lower surface by being pressed upward by the tips of adjusting screws 8, 8' carried by leaf springs 7, 7' fixed to the main body 4 with screws 6. These adjusting screws 8, 8' are connected to the leaf spring 7,
It is screwed into a screw hole provided at the tip of 7' and locked at a predetermined adjustment position with lock nuts 8a, 8a'.

FIG. 2 shows details of the electrode portion on the lower surface of the main body 4, and it can be seen that the lower electrode 2 is supported from both sides by leaf springs 7, 7'.

The upper end portion of the insert 5 protrudes upward from the main body 4, and a stopper ring 10 is fitted into a threaded portion provided on the outer periphery of the protrusion. When the upper electrode, that is, the screw member 1 is completely screwed in by rotating the handle 9, the ring 9' of the handle 9 comes into contact with the stopper ring 10. By appropriately adjusting the fitting amount of the stopper ring 10, the distance between the upper electrode 1 and the lower electrode 2 can be adjusted to a predetermined distance L. This is taken as the electrode spacing during adjustment. A peripheral wall 2' is provided on the side of the lower electrode 2, and serves as an introduction guide for the sample dish 2a shown in FIG. The upper end of the peripheral wall 2' abuts against the lower surface of the step in the opening of the main body 4.

As shown in FIG. 3, when a fixed amount of grain sample is placed in the sample dish 2a and held between the electrodes 1 and 2, the lower electrode 2 is further displaced downward by a distance l from the state shown in FIG. Therefore, the distance between electrodes 1 and 2 is L+l. This is taken as the electrode spacing during measurement.
If the leaf springs 7 and 7' are deteriorated and defective, even if the sample plate 2a containing a predetermined amount of sample is held between the electrodes 1 and 2, the predetermined pressure between the electrodes will not be obtained, and the moisture value will not be indicated correctly. .

In order to timely measure the inter-electrode pressure and obtain a predetermined inter-electrode pressure, it is necessary to adjust the spring force of the leaf springs 7, 7' using adjustment screws 8, 8'.

FIG. 4 shows a pressure sensitive gauge 20 according to the invention for measuring interelectrode pressure. This pressure gauge 20
is sandwiched between electrodes 1 and 2 of the moisture meter as shown in FIG. In other words, the sample tray insertion port 4 of the moisture meter
It is inserted from a and held between the electrodes.

In FIG. 4, the pressure sensitive gauge 20 is composed of a substrate 21 and an upper plate 22. As shown in FIG. The upper plate 22 has holes 23
The protrusion 24 of the substrate 21 is fitted into the hole 23, whereby the upper plate 22 and the substrate 21 are assembled. A recess 25 is provided in the free end of the substrate 21, and a pressure measuring film 26 is inserted into this recess 25.

5 and 6 show a bottom view and a sectional view of the upper plate 22, respectively.

A plurality of concentric annular protuberances are provided on the lower surface of the upper plate 22 in a portion facing the recess 25 of the substrate 21. These annular protuberances are collectively designated by the reference numeral 27. When the upper plate 22 and the substrate 21 are aligned and overlapped, the annular protrusion 27 enters the recess 25 of the substrate 21 and presses the pressure measuring film 26.

When the pressure-sensitive paper 26 is inserted into the recess 25 of the substrate 21 and the substrate 21 and the upper plate 22 are aligned and overlapped, the thickness of this combination is a size suitable for measuring the pressure between the electrodes. It is necessary to

This thickness can be determined experimentally based on the relationship between the degree of color development of the pressure measurement film and the predetermined interelectrode pressure. Although it varies depending on the electrode structure of the grain moisture meter, it is determined between the above-mentioned interval L during adjustment and interval L+l during measurement. In FIG. 4, a color code table 28 is provided on the upper surface of the upper plate 22, and after the pressure sensitive gauge 20 is held between the electrodes, the color code table 28 is compared with the degree of coloring of the pressure measurement film 26. It is possible to know the pressure between the two.

A method of measuring interelectrode pressure of a moisture meter using the pressure sensitive gauge 20 of the present invention will be described below.

A new pressure measuring film 26 is inserted into the recess 25 of the substrate 21, the substrate 21 and the upper plate 22 are aligned and overlapped, and the electrode 1 is inserted from the sample plate insertion opening 4a of the moisture meter as shown in FIG. , insert between 2. Next, screw the handle 9 of the moisture meter until the ring 9' abuts against the stopper ring 10, and the pressure sensitive gauge 2
0 is sandwiched between the electrodes. For this reason, the annular ridge 27
presses the pressure measuring film 26. The pressure measurement film develops color depending on the degree of pressing force. From between the electrodes, loosen the handle 9, take out the pressure-sensitive gauge 20, and then take out the pressure-measuring film 26 from the pressure-sensitive gauge 20, and observe the degree of color development. The pressure value is obtained by comparing the degree of color development with the color code table 28. If the pressure value deviates from the predetermined interelectrode pressure, adjust the adjusting screws 8, 8' of the moisture meter by loosening the lock nuts 8a, 8a', and measure the interelectrode pressure using the pressure sensitive gauge 20 again.

The above adjustment of the adjustment screws 8, 8' for measuring the interelectrode pressure is repeated alternately until a predetermined interelectrode pressure is obtained.

A pattern corresponding to the plan view of the annular protuberance 27 should be observed on the pressure measurement film 26 of the pressure-sensitive gauge 20 taken out from between the electrodes, but this pattern was observed along the periphery to determine the degree of color development. By checking, the local pressure on the surfaces of the electrodes 1 and 2 can be determined. With this, the left and right adjustment screws 8,
8' can be adjusted individually to average out the spring forces of the springs 7, 7' respectively. Note that this raised body 27 does not need to be annular, and may be lattice-shaped. In short, it is sufficient if the tendency of the pressure distribution on the surfaces of the electrodes 1 and 2 can be known.

The pressure-sensitive gauge according to the present invention can be provided at a low cost, so if it is attached as an inspection gauge to the electric resistance type grain moisture meter that is currently commonly used by farmers, each farmer can check and adjust the pressure between the electrodes. By making adjustments, the measurement accuracy of the moisture meter can always be maintained at a predetermined level, and the moisture meter can be used with confidence during the rice harvesting season.

Although the present invention has been described above in the form of embodiments, the present invention is not limited to these embodiments and can be modified in various ways within the scope of the claims.
For example, the pressure sensitive gauge 20 is a combination of a substrate 21 and an upper plate 22, but the upper plate 22 is eliminated and the upper electrode 1 is inserted directly into the recess 25 of the substrate 21 to press the pressure measuring film 26. Also good. Furthermore, it is within the scope of the present invention that the pressure measuring film 26 may be attached directly onto the substrate 21 without providing the recess 25 therein.

In this case, the substrate 21 is turned over and inserted between the electrodes.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a cutaway view of the main parts of an electrical resistance moisture meter. FIG. 2 is a diagram showing a main bottom view of the electrical resistance moisture meter. FIG. 3 is a diagram showing the usage state of the electrical resistance moisture meter in the same manner as FIG. 1. FIG. 4 is a transparent diagram of the pressure-sensitive gauge of the present invention. FIG. 5 is a bottom view of the parts shown in FIG. 4. FIG. 6 is a sectional view taken along the - line in FIG. 5. FIG. 7 is a partially cutaway view of the main parts when the pressure-sensitive gauge of the present invention is used in an electrical resistance moisture meter. 1, 2... Electrode, 4... Moisture meter body, 5... Insert, 6, 6'... Lock nut, 7, 7'...
...Plate spring, 8, 8'...Adjusting screw, 9...Handle, 9'...Ring, 10...Stopper ring,
20...Pressure sensitive gauge, 21...Substrate, 22...Top plate, 23...Hole, 24...Protrusion, 25...Recess,
26... Pressure measurement film, 27... Annular protuberance,
28...Color code table.

Claims (1)

[Scope of Claims] 1. In a method for adjusting the pressure between the electrodes of an electrical resistance moisture meter, which measures the moisture content of grain by sandwiching a grain sample between electrodes at a predetermined distance and applying a predetermined pressure, (a) arranging a pressure sensitive film on a substrate having a thickness substantially equal to the predetermined distance; (b) sandwiching the substrate between the electrodes and applying pressure; (c) removing the substrate from between the electrodes. , a step of determining the pressure between the electrodes based on the degree of color development of the pressure-sensitive film, and adjusting the elastic force of the elastic member acting between the electrodes based on this pressure; (d) performing the above (b) and (c) as necessary; A method for adjusting the inter-electrode pressure of an electric resistance grain moisture meter, comprising: repeating the steps to set the inter-electrode pressure to the predetermined inter-electrode pressure. 2. In a pressure-sensitive gauge for measuring inter-electrode pressure used in an electrical resistance moisture meter that measures the moisture content of grain by sandwiching a grain sample between electrodes at a predetermined distance and applying a predetermined pressure, the predetermined distance is A substrate with a thickness approximately equal to
A pressure-sensitive gauge having a pressure-sensitive film for pressure measurement disposed on the substrate. 3. The pressure-sensitive gauge according to claim 2, which has a color code table. 4 In a pressure-sensitive gauge for measuring pressure between electrodes used in an electrical resistance moisture meter, which measures the moisture content of grain by sandwiching a grain sample between electrodes at a predetermined distance and applying a predetermined pressure, and a pressure sensitive film for pressure measurement disposed on the bottom surface of the recess, the thickness of the bottom surface of the recess being approximately equal to the predetermined interval distance. 5. The pressure-sensitive gauge according to claim 4, which has a color code table. 6. In an electrical resistance moisture meter that measures the moisture content of grain by sandwiching a grain sample between electrodes at a predetermined distance and applying a predetermined pressure, a substrate, an upper plate disposed on the substrate, and a a pressure sensitive film for pressure measurement disposed between the upper plate and the substrate;
A pressure sensitive gauge in which the total thickness of the upper plate and the substrate is approximately equal to the predetermined interval. 7. The pressure-sensitive gauge according to claim 6, which has a color code table. 8 A recess is provided in a pressure-sensitive gauge for measuring pressure between electrodes used in an electrical resistance moisture meter, which measures the moisture content of grain by sandwiching a grain sample between electrodes at a predetermined distance and applying a predetermined pressure. a top plate having a raised body on one surface that is fitted into the recess, and a pressure sensitive film for pressure measurement disposed on the bottom surface of the recess, the raised body being fitted into the recess. , a pressure sensitive gauge in which the total thickness of the upper plate and the substrate at the fitted portion when the upper plate is overlapped with the substrate is equal to the predetermined interval distance; 9. The pressure sensitive gauge according to claim 8, wherein the raised body is a plurality of concentric annular raised bodies. 10. The pressure-sensitive gauge according to claim 8, wherein the raised body is a plurality of raised bodies in a lattice shape. 11. The pressure-sensitive gauge according to claims 8 to 10, which has a color code table.