JPS60122324A - Impaction type flowmeter - Google Patents

Abstract

PURPOSE:To manufacture with high accuracy an impacting force detector of long service life and maintenance free by composing the gauge so that only a horizontal load is detected by using a shear pin type load cell. CONSTITUTION:An impaction type flowmeter is composed so that powdery granules falling down from a feeding chute 21 impinge to a inclined pressure receiving plate 23, lose the kinetic energy and slide down on the plate 23. The kinetic energy is given to the load cell 25 as impacting force through an attaching metal fitting 24. The cell 25 is fixed to an attaching base 26, and only the horizontal partial force among the impacting force is detected by the attaching direction. By such a constitution, the structure in which only the load of one component is detected by one load cell and another loads are not detected at all can be manufactured, and the impacting force detector of high precision, long service life and maintenance free can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact type flow meter that detects and measures the flow rate of continuously falling powder or granular material by a load cell while receiving it on a pressure receiving plate that is inclined with respect to the falling direction.

In this type of flowmeter, the flow rate of the falling powder is proportional to the impact force that collides with a pressure receiving plate installed during the fall. The impact force F is N lower height 11 feet higher, where: constant of proportionality, m: amount of falling material, and g: acceleration of gravity.
F= becomes @meg*h. Therefore, to calculate the mass m,
It is sufficient to measure the impact force F.

By the way, since the powder to be measured falls continuously, it is not preferable for it to stay on the pressure receiving plate, and the pressure receiving plate is installed at an angle so that it will slide off immediately upon impact. However, while sliding down the pressure plate, the powder becomes a static load that applies a load in the vertical direction, and depending on how the pressure plate is installed, it may generate a torsional moment or may be damaged due to its resistance to adhesion to the pressure plate. The zero load also changes. Therefore, when making measurements, remove vertical static loads and torsional moments.
Only pure impact loads must be detected.

The impact force F of a fall is decomposed into each component, but as shown in Figure 1, the component Fn perpendicular to the pressure plate is divided into the vertical and horizontal components Fv.
Decomposed into Fh. Of these, static loads and zero changes are also added to the vertical component Fv, so only the horizontal component Fh must be detected as the pure impact force.

Conventionally, a mechanically complicated link mechanism or the like has been used to achieve this. One example is the parallel link mechanism shown in FIGS. 2 and 3.

The load applied to the pressure receiving plate 1 is restricted to movement only in the horizontal direction by the parallel links 3 and 3', and all other functions are restricted. An initial load application spring 5 is installed between the load frame 2 and the fixed frame 4 for stability. A link 6 for direction conversion is added to the load frame 2, and a load cell 7
A compressive load is applied to the

This type of structure allows movement in only one direction for all loads and restricts everything else, so the purpose is achieved, but
Each bin/link is subject to constant load and is prone to wear, and since there are many rotating pairs, dust countermeasures are required, and measures such as placing the mechanism in a sealed case and applying an air barge are also required. .

Therefore, the present invention aims to eliminate all the various drawbacks of the above-mentioned conventional mechanisms and to realize a simple, high-accuracy, long-life impact type flowmeter, by simply using one load cell. The present invention is characterized by obtaining a flowmeter having no moving parts. Next, the details will be explained.

A Shapin type load cell is a load sensor that detects the shear force due to the load applied to a flexure body and measures the applied load, and one of them has the structure shown in Figures 4 and 5. There is.

That is, flat parts 11 and 12 are provided at the front and back of the side surfaces near both ends of the strain-generating body 10, which is a steel round bar supported at both ends, and four gauges 13 and 131 are arranged at an angle of 45 degrees around the neutral plane.
．． 14 and 141 are pasted on each of the front and rear surfaces 11-12.

The shear force generated in the ribs supported at both ends or fixed at both ends is as shown in Figure 6. This shear type load cell is shown in Fig. 7 Φ 8
Rotate it 90 degrees as shown in the figure, position the gauge face up and down, and install it so that it can detect the load in the horizontal direction.

An example of the structure is shown in FIG. 9 and FIG. 10.

The powder and granules that have fallen from the input plate 21 are transferred to the inclined pressure receiving plate 23.
The object collides with the object, loses kinetic energy, and slides down on the pressure receiving plate 23. The energy of this movement becomes an impact force and is applied to the load cell 25 via the mounting bracket 24. The load cell 25 is fixed to a mounting base 26, and depending on the mounting direction, only the horizontal component of the impact force is detected. The load cell output is led to an amplifier (not shown) by a cable 27, and after being amplified to a required amount, is input to the arithmetic circuit. 22 is a case that prevents external influences such as wind.

In the above configuration, the load cell 25 is attached in the manner shown in FIG. The strain gauge 13, 13□, 14
・14□ is constructed into the bridge shown in FIG. 11 using a well-known method, and cage 13=R2, 13r=R1, 14=R3,1
The correspondence relationship is 4□=R4.

Therefore, if we consider the output for each direction of force, we will get the following.

The applied voltage is E and the output voltage is eo.

Further, this circuit requires temperature compensation, gauge zero point adjustment, span adjustment, etc., but these are omitted.

Since the output e0 is the potential difference between the C and D terminals, the relationship between each resistor is RI R4R2' R3=0 when the load is zero and the output is zero.Usually, equal resistors are used.

The output for the horizontal force Fh is a positive change, a negative change gauge, and △R is the change in each gauge. 13. 14113 14 Resistance value R+ R4R2R3 Change value +△R+ΔR-ΔR-△R Substituting this into (1) (R++ΔR+R3-ΔR) (R2-△R+R4+ΔR
) (R1+R3) (R2+R4) If all resistance values are equal, then 4R2R Positive change for vertical force Fv Negative change gauge 14 14t 13 13, Resistance value R3Ra R2R+ Change value +ΔR+ΔR-ΔR-ΔR (R+-ΔR+R3-ΔR )(R2-△R+R4+ΔR
)(R+ "R3) (R2+RA) R, = R2 = = R, = l (If it is 4, the numerator of the above equation will be zero, so eo = O, and no output will be produced even if a vertical load is applied.

Positive change and negative change gauge for torsional moment Ft 13 14. 13114 Resistance value R2R4Rs R3 Change value +ΔR+ΔR-ΔR-ΔR (R4+R32ΔR) (R2+R, +2ΔR) R1+R
2-R3-R4=0 As will be understood from this, the present invention can detect only one component of load with one load cell, and can manufacture a structure that does not sense other loads at all. . Also, compression type load cells are weak against lateral loads and can cause failure.
Shapin type load cells have strong resistance against loads in any direction.

As a result, we were able to create a highly accurate, long-life, maintenance-free impact force detector by simply attaching a pressure plate directly to this load cell.

[Brief explanation of the drawing]

Figure 1 is a component diagram of a falling impact force on an inclined pressure receiving plate.
Figures 2 and 3 are a plan view and a side view of a conventional impact type flowmeter, Figures 4 and 5 are a front view and a cross-sectional view of a chapin-type load cell, and Figure 6 is the shear force of the support beams at both ends. Figure, Figure 7・
Fig. 8 is a front view and a cross-sectional view of a Shapin type load cell used in the present invention, Figs. 9 and 10 are a side view and a front view showing a specific example of the flow meter of the present invention, and Fig. 11 is a strain gauge. bridge circuit. 10 is a strain body, 13, 13□, 14I114t are strain gauges, 23 is a pressure plate, 24 is a pressure plate mounting bracket, and 25 is a load cell. Patent applicant: Higashi Hoshiki Industry Co., Ltd. Agent: Fuku 1)

Claims (1)

[Claims] (1) In an impact-type flowmeter that detects and measures the flow rate of continuously falling powder and granular material using a load cell after receiving it on a pressure-receiving plate that is inclined with respect to the falling direction, only a horizontal load is detected using a Shapin-type load cell. An impact type flowmeter characterized in that the gauge is configured to detect.