RU2002223C1 - Method for determining height of column of colourless balancing liquid in measuring tube with transparent wall - Google Patents

Description

The invention relates to measuring equipment, in particular to liquid pressure gauges and level gauges in the form of an index glass (column),

Known liquid manometer containing a measuring channel with transparent walls and with a working fluid, and the channel is placed between the transparent scale and the backlight. The scale is made in the form of a rectangular prism, on the front and back faces of which there are divisions. The column height of the balancing liquid is measured by the meniscus observed through the transparent walls of the measuring tube or through a rectangular transparent prism with a scale.

The disadvantage of this method is that a more or less clear meniscus is observed only near the measuring tube, i.e. visual determination of the height of the column of balancing liquid at a certain distance from the observer is difficult.

Closest is a method for determining the height of a column of a colorless balancing liquid in a measuring tube with transparent walls when it is illuminated. The backlight is on the back of the screen, and the screen itself is made light-absorbing with a gap of not more than the inner diameter of the tube along its entire length. During illumination, due to the difference in the refraction of light in media of different densities, the effect of an imaginary color of the liquid arises, which allows you to get a clearly defined liquid boundary, which is easily visible during visual readout and clearly captured in the photograph. Thus, the screen is located between the light source and the measuring tube and serves only to form a light stream of the required geometry 2.

The disadvantage of this method is that a more or less clear meniscus can only be observed near a column of balancing fluid. The illumination of the measuring tube with a colorless balancing liquid was mainly used so that when photographing the readings of the liquid differential pressure gauge, the boundaries of the liquid levels were sufficiently clear.

In Fig, 1 and 2 shows a diagram of devices that implement the proposed method.

Figure 1 shows the measuring tube 1 with a lenticular cross-section, and figure 2 with a round,

In both schemes, the measuring tube 1 together with a linear light source 2,

parallel to it and along the entire length of the tube, enclosed in a housing 3, A tube with transparent walls filled with an optically transparent liquid

and a round or lenticular cross-section works like a cylindrical collecting lens in contrast to an empty tube.

When illuminating the measuring tube,

filled with an optically transparent liquid, a luminous flux with a paraxial direction of its rays on the screen 4, is located in close proximity to the rear focal plane of the cylindrical

5 of the lens formed by the transparent walls of the measuring tube 1 and the colorless liquid filling it, a distinct invention of the dark boundaries of the tube 1 corresponding to its geometric

0 shadow, and located inside their sharply allocated bright strip.

Obviously, in the case when an optically transparent liquid fills part of such a tube1, the bright strip on the screen 4 will be

5 correspond only to the height (length) of the filling.

The fundamental difference between the above schemes lies in the fact that on fmg.2 channel a band of width S is observed

0 through a thin diffusion transmission screen 4 with a scale printed on it, and in FIG. 1, it can be observed both through a diffusion transmission screen and on a diffusion reflection screen. The distance characterizing the position of the rear focal plane of the collecting lens formed by the transparent walls of the measuring tube and the optically transparent liquid filling it, depends on

0 from the geometry of the cross-section of the measuring tube 1, and from the indicators of the liquid and the material of the tube.

According to the scheme shown in Fig. 2, a device was assembled consisting of a glass tube 5 with an outer diameter of 5.5 mm, an inner diameter of 2.8 mm and a length of 950 mm. The screen with a scale was made of milk glass. A light-absorbing coating was applied to the inner surface of the housing.t

Studies have shown that when using water as a balancing liquid, the brightness of the luminous strip on the screen is quite sufficient, so as not to impose any requirements on the illumination of the working room (external lighting) and to observe this strip at any distance from which it is clearly distinguishable dividing the scale on the screen; the border of the bright strip on the screen corresponds to the position of the meniscus of the column of balancing fluid in the measuring tube.

The use of the invention improves the reliability of visual determination of the height of the column of a colorless (slightly colored) balancing liquid in

Claims (2)

The claims METHOD FOR DETERMINING THE POST HEIGHT OF A COLORLESS EQUILIBRIUM LIQUID IN A MEASURING TUBE WITH TRANSPARENT WALLS, having a round or lenticular cross-section, in which it is illuminated with a luminous flux, characterized by the fact that the visual height is used to increase the height of the table measuring tube with transparent walls. (56) 1. USSR Copyright Certificate No. 1585695. cl, G 01 L7 / 18, 1990, 2. USSR author's certificate No. 553496. class. G 01 L 7/18, 1977. They form a stream with a paraxial direction of its rays, in the immediate vicinity of the rear focal plane. A cylindrical collecting lens formed by the transparent walls of the measuring tube and filling it with a colorless liquid, have a screen with a scale applied on it, and about the height of the column of the suspension liquid in the measuring tube is judged by the position of the border of the bright strip on the screen scale.