JPS5834332A - Wall surface loam pressure gauge - Google Patents

Abstract

PURPOSE:To facilitate fitting and to reduce a variation in an initial unbalanced value, by providing a fitting flange for fitting to the wall surface of a body to be measured to the bottom part of a case, and increasing the flange part and the cylinder part of a strain inducing cylinder in rigidity. CONSTITUTION:When powder and granules are deposited on the fitting wall of a part to be measured to load its weight statically, a pressure receiving plate 7 is loaded vertically at its pressure receiving surface part 7a to deform in the axial direction of a cylinder. The pressure receiving plate 7 has large rigidity, so its extent of flection is slight and the plate only moves in the axial direction. The displacing force of this pressure receiving plate 7 in the axial direction is transmitted to a diaphragm 8b through a transmission rod 9 to flex the diaphragm 8b greatly and also transmitted to a circular ring plate 10 to deform the plate 10. The extent of flection of the this diaphragm 8 is converted by a strain gauge 12 into the quantity of electricity, which is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wall soil pressure meter which is attached to a wall surface 9 and is used to detect the vertical stress received from a fluidized powder material such as fluidized sand grains on the wall surface.

As shown in Fig. 1, the conventional earth pressure gauge has a double diaphragm structure consisting of a large-diameter primary diaphragm 1 as a pressure-receiving surface and a small-diameter secondary diaphragm 3 to which a strain gauge 2 is bonded. A mercury filling chamber 4 is provided by reducing the gap with the secondary diaphragm 3, and mercury is sealed therein to convert the vertical load applied to the pressure receiving surface into fluid pressure.

Due to the fluid pressure, the minute displacement of the pressure receiving surface is transmitted to the secondary diaphragm 3 at an expansion rate approximately proportional to the square of the diameter ratio of the two diaphragms, and the strain gauge 2 bonded to the diaphragm 3 can detect it with high sensitivity. It is composed of

As shown in FIG. 2, another example of a conventional soil pressure meter has a primary diaphragm structure including a bottomed cylindrical case 5 and a diaphragm 6 mounted on the open end side of the cylindrical case 5. In the diamond 7 ram 6, the center part is formed thickly to form a pressure receiving surface part 6a, and the peripheral part 9 is formed thinly to form a strain generating part 6b.

Furthermore, the peripheral edge is made thinner to form a crown fitting part 6c for attaching to the cylindrical case 5, and a strain gauge 2 is bonded to the inner surface of the strain generating part 6b, so that the vertical load applied to the pressure receiving surface part 6a can be reduced. It is configured so that it can be detected by a strain gauge 2 bonded to the strained portion 6b.

However, when these conventional soil pressure gauges are installed on a wall, the soil pressure gauge itself is deformed. In the case of the above example, since the strain generating portion 6b is deformed, there is a problem that the initial unbalance value changes significantly. Ushida, Jy: When the surface itself is deformed.

As a result, the earth pressure gauge n-body is also easily deformed, and there is a possibility that it may detect a vertical stress that is different from the true value. It's even smaller
In the former example, the -order diaphragm 1 and in the latter example, the strain-generating portion 6 of the diaphragm 6 are both thin, so they are weak against shock and easily abraded, resulting in a change in output voltage sensitivity. There is a problem that Yet again. In particular, as in the former example, there is a risk of mercury leakage in the mercury-filled type, so it is suitable for detecting fluid pressure in food products.

The problem is that it cannot be used.

The present invention was made to solve these problems, and it is easy to install on a wall, and there is little change in the initial unbalance value, and the earth pressure gauge itself is less likely to be deformed due to deformation of the wall itself. The pressure-receiving plate has high impact resistance, so the output voltage sensitivity is not affected by wear, so it can be used with confidence for detecting the pressure of not only food products but also all fluid powder and granular materials.

It is an object of the present invention to provide a wall soil pressure gauge that can reduce the amount of deflection of a pressure receiving plate under conditions where the amount of output equivalent strain at rated output is constant.

In other words, the gist of the present invention is to connect a pressure receiving plate with high rigidity and a diaphragm with low rigidity formed at one end of a highly rigid strain tube through a transmission rod, and to The side periphery of the cylinder is connected to the bottom of a bottomed cylindrical case having a mounting flange with a high rigidity and the other end of the strain-generating cylinder through a circular plate having elasticity and low rigidity. Install it.

The pressure receiving plate and the strain cylinder are housed in the bottomed cylindrical case with the pressure receiving surface of the pressure receiving plate exposed, and the vertical load applied to the pressure receiving plate is transmitted through the transmission rod. The strain is transmitted to the diaphragm of the strain tube, and the amount of strain generated in the diaphragm is converted into an electrical output by a strain gauge attached to the diaphragm and extracted.

An embodiment of the present invention will be described in detail below with reference to two drawings.

FIG. 3 is a partially cutaway front view showing the configuration of one embodiment of the present invention.

In the figure, reference numeral 7 denotes a pressure-receiving plate having a cylindrical shape with an open bottom and a bottom pressure-receiving surface 7a formed thickly to increase rigidity, and an annular groove 7b formed on the side circumferential surface thereof. A female thread 7e is formed at the center of the inner surface (back surface) of the pressure receiving surface portion 7a. 8 is a strain-generating cylinder in the shape of a bottomed cylinder with openings at all ends, and the cylindrical portion 8a has a thickness of -5 to increase rigidity.
-171 The diaphragm 81) at the bottom is formed thin to reduce rigidity, and the diaphragm 81) is formed thinly at the center of its surface.

On the side periphery of the two cylinders to which the transmission rod 9 having a male thread 9a is fixed, a thin-walled brim-like elastic circular plate 1o with low rigidity extends in a direction perpendicular to the side periphery. circular plate 10
A contact portion 10a having approximately the same thickness as the open end 7C of the pressure receiving plate 7 is formed at the peripheral end of the pressure receiving plate 7, and a female thread 8d is formed at the open end 8c. Reference numeral 11 denotes a bottomed cylindrical case having an open end at one end and a mounting 7 flange on the closed end (bottom) side, at least the mounting 7 flange lla and the bottom 11.
b is formed to have a thick wall to increase rigidity, and this mounting flange lla.

An insertion hole 11c for a tightening bolt for attaching this earth pressure gauge to the part to be measured is bored, and the bottom part 111) of this case 1
An insertion hole 11 [1] for a tightening bolt 17 for connecting the strain tube 8 and the strain tube 8 is bored.

The cylindrical portion lie is formed at a height such that when the strain cylinder 8 and the pressure receiving plate 7 are assembled into the case 11, the surface becomes approximately the same as the pressure receiving surface portion 7a of the pressure receiving plate 7. . Reference numeral 11f denotes a circumferential groove having a concave cross section formed on the inward upper surface of the seven flange portions 11a. Reference numeral 12 denotes a strain gauge, which is bonded to the inner (back) side of the diaphragm 81). 13 is the cable pull-out part, case 1
1 by means of screwing, welding, etc.

Inside, a gauge lead 14 connected to the terminal of the strain gauge 12 is connected to a cable 15 drawn out to the outside and connected to a strain gauge. 16d: An O-ring for tooling that is fitted into the annular groove 7) of the pressure receiving plate 7 with a portion protruding. Numeral 17 is a tightening bolt for attaching the strain tube 8 to the case 11.

The pressure receiving plate 7 and the strain cylinder 8 are connected by screwing the male thread 9a of the transmission rod 9 fixed to the strain cylinder 8 into the female thread 7e formed on the pressure plate 7. At this time, the open end 7c of the pressure receiving plate 7 and the contact portion 10a of the annular plate 10 come into contact. This contact portion is fixed by welding. The strain tube 8 assembled in this way is attached to the case 11 by attaching the tightening bolt 1.
7 is inserted into a hole lid drilled in the bottom 111 of the case 11 and screwed into a female thread 86 formed in the bottom of the strain cylinder 8.

At this time, the inner peripheral surface of the cylindrical portion 11c of the case 11 and the pressure receiving plate 7
The outer circumferential surface is watertightly sealed by the ring 16 and is connected to the pressure receiving surface portion 7a of the force receiving plate 7 and the case 11.
The opening end surface of the cylindrical portion lie is almost the same as that of the cylindrical portion lie. Mounting wall 18 (for example, a pipe wall for pumping earth and sand)
Apply a mounting jig 19 of an appropriate thickness, adjust the pressure receiving surface portion 7a of the pressure receiving plate 7 to be flush with the mounting wall 18, and fix the mounting wall 18 and the mounting jig 19 by welding. After that, the case 11 is fitted into the holes made in the mounting wall 18 and the mounting jig 19. Then tighten the tightening bolt 20 to 7 langes 1.
1. the case 11 by inserting it into the hole 11c drilled in
is attached to the mounting wall 18 via the mounting jig 19.

The O-ring 21 inserted between the second mounting flange lla and the mounting jig 19 is provided to prevent fluid from leaking to the outside. In this way, the wall where the wall soil pressure gauge was installed was covered with earth and sand.

When granular materials such as grains and ores are accumulated and their weight is applied statically, or when a fluid granular material moves and its dynamic load is applied, the pressure receiving plate 7 is perpendicular to its pressure receiving surface 7a. load(
or pressure) and is displaced in the axial direction of one cylinder. At this time, since the pressure receiving plate 7 has a rigid structure, the amount of deflection is so small that it can be ignored, and there is only a slight movement in the axial direction.

The displacement force in the axial direction of the pressure receiving plate 7 is transmitted to the diaphragm 8b via the transmission rod 9, greatly bending the diaphragm 81), and extending from the open end 7C of the pressure receiving plate 7 to the strain tube 8. It is transmitted to the circular plate 10 that has been rotated, thereby deforming the circular plate 10.

The amount of deflection of the diaphragm 81) is converted into an electric machine by a change in the resistance value of the strain gauge 12 bonded thereto, and is then converted into pressure and displayed or recorded.

In this way, according to the above embodiment, first of all, the mounting 7 langes for mounting on the wall surface of the object to be measured are provided at the bottom of the case. Since the part is formed to have high rigidity,
Changes in the initial unbalance value when adding soil pressure gauges to the wall can be minimized.

Second, for the same reason as above, deformation of the wall soil pressure meter itself occurs due to deformation of the wall surface itself.

Therefore, even if there is deformation of the wall surface itself, little of it is transmitted to the diaphragm, and the true value of wall surface normal stress can be detected and measured.

Thirdly, since the rigidity of the receiving plate itself is increased, it is strong against impact, wear due to sliding movement of earth and sand, etc. can be almost ignored, and output voltage sensitivity is not affected.

Fourthly, if the pressure receiving plate has high rigidity and the i1+11 constant wall surface and the pressure receiving surface are aligned almost on the same plane, there will be no protruding parts that impede the movement of powder and granules, so the pressure receiving plate surface will move horizontally (sliding direction). The force is transmitted <<, and even if a lateral force is transmitted to the pressure receiving plate, the strain gauge is arranged so that it is insensitive to the lateral direction, and the circular plate functions relatively rigidly in the radial direction. Therefore, the inclination of the pressure plate is prevented, d: I, and a bending moment is applied to the diaphragm to which the strain gauge is bonded, making it difficult to t. Almost no lateral force is applied to the upper surface of the cylindrical part of the case, but even if it were applied, the structure is such that it is difficult to transmit to the pressure receiving plate and the diaphragm of the strain tube. Therefore, it is not affected by forces from the lateral direction.

Fifth, there are no dangerous substances such as mercury inside the wall soil pressure gauge, so
It can also be safely used to measure the pressure of fluidized powder particles such as foods.

Sixth, by changing the two thicknesses of the diaphragm and the circular plate extending around the strain cylinder, the amount of deflection of the pressure plate at the rated output and the output equivalent strain can be adjusted. The amount of distortion can be adjusted, and a larger output equivalent strain amount can be detected with a smaller amount of deflection.

Seventh, since an O-ring is interposed as a watertight means between the inner peripheral surface of the case and the outer peripheral surface of the pressure receiving plate, water, powder, etc. are prevented from entering the case, and the displacement of the pressure receiving plate is prevented. There is no problem with the operation, and since moisture does not enter the case, performance deterioration due to moisture absorption of the strain gauge can be prevented. Since the strain gauge is enclosed in a strain cylinder, even if water leaks from the ring part and enters the case, it will not penetrate the strain gauge.

Note that the present invention is not limited to the two consecutive embodiments, and various modifications can be made without changing the gist thereof.

For example, in the above embodiment, the flange +17 is integrated with the case, but it may be formed as a separate part and then integrated by screwing or welding, or it may be integrated with the strain cylinder. The case may be integrally molded.

Also, this soil pressure gauge can be applied to.

In addition to wall earth pressure at the foundations of dams and buildings, it can be installed on the tip of excavation blades used in ore mining, tunnel excavation, etc., on the walls of silos and hoppers, on the walls of pulverized coal pumping vibrators, etc., to measure the wall surface pressure. can be measured.

As described in detail below, 1. According to the present invention, it is easy to provide ground to the wall surface, and at the same time, there is little change in the initial unbalance value.
It is not affected by the deformation of the wall itself, the pressure receiving plate has excellent shock control properties, and the output voltage sensitivity is not affected by wear.
It is possible to provide a wall soil pressure gauge that can be safely used to detect the pressure of all liquid powder fluids as well as food products, and can reduce the amount of deflection of the pressure receiving plate under the condition that the output equivalent strain amount at the rated output is constant.

[Brief explanation of the drawing]

1 and 2 are sectional views showing the configuration of a conventional soil pressure meter, FIG. 3 is a partially cutaway front view showing the configuration of an embodiment of the wall soil pressure meter according to the present invention, and FIG. 4 is the same. FIG. 2 is a partially cutaway front view showing the embodiment attached to a wall. 7... Pressure receiving plate 7a... Pressure receiving surface portion 8... Strain cylinder 81)... Diaphragm 9... Transmission rod 10... Annular plate 11... Case 11
;I...Several phrases flange 12...Strain gauge 13
... Cable pull-out part 16, 21 ... 0 ring 18
...Kyowa Dengyo Co., Ltd. Patent applicant for several phrase walls

Claims (1)

[Claims] A pressure receiving plate with high rigidity and a diaphragm with low rigidity formed at one end of a highly rigid strain tube are connected via a transmission rod,
The pressure receiving plate and the side circumferential portion of the strain tube are connected through a circular plate having elasticity and a small degree of rigidity, and the other end of the strain tube has a bottomed cylindrical shape having a mounting flange with high rigidity. The pressure receiving plate and strain cylinder are housed in the bottomed cylindrical case via watertight means by attaching the bottom part of the case and exposing the pressure receiving surface of the pressure receiving plate. A load is transmitted to the diaphragm of the strain tube via the transmission rod, and the amount of strain generated in the diaphragm is converted into an electrical output by a strain gauge attached to the diaphragm and taken out. Wall soil pressure gauge.