SU131554A1 - Device for measuring and fixing angular velocity instability - Google Patents

Description

Devices for measuring and fixing angular velocity instabilities are known, comprising a periodically lit illuminator, a condenser, a diaphragm and a lens, by means of which a beam of light is projected onto a photographic film.

Such devices do not provide high accuracy of measurement, since the light marks partially overlap each other.

In the device described, this disadvantage is eliminated by using an inclined mirror mounted on the end of the rotating shaft, the instability of the angular velocity of which is measured, and serving to reflect the light beam directed at it onto the photo paper placed inside the drum.

FIG. 1 shows a schematic representation of the described device; in fig. 2, 3, 4, 5 - the image of light marks on photo paper.

The illuminator / ignitor installed inside the pipe with blackened walls at regular intervals. The light note from the illuminator 1 is formed by a condenser 2 of the diaphragm 3 and the lens 4 into a rectangular beam incident on an inclined mirror 5 mounted on the end of the controlled drum shaft 6.

The mirror 5 projects the light beam onto the photographic paper 7 placed inside the drum, which, in order to avoid overlapping the light marks, moves with the photographic paper 7 along the axis of rotation of the shaft 6. To prevent the photographic paper 7 from moving, the lever system 8 is connected gearboxes 10. The drum is moving at a constant speed along the guides.

When the mirror 5 is rotated, the luminous rectangle of the helix aa the surface of the photo paper 7 helix with pitch S. Since the illuminator 1 is ignited in equal time intervals, on the photo paper 7

No. 131554-2 illuminates individual sections in the form of a helix dotted line (Fig. 2). Having unfolded the paper, a series of dashed lines is obtained (Fig. 3).

Each such line represents a sweep of one pitch of the helix and repeats the size and location of the first line if the velocity under study is stable and equal to the theoretical one.

The number of vertical bars p ij

where / „is the frequency of the module 1, and the light source, and n is the speed of the axis studied, rev / min.

If the speed of the investigated part is stable and differs from the theoretical one by D, then each line will repeat the length of black lines and white gaps, and the location of each subsequent line will be shifted relative to the previous and D / f value (Fig. 4).

The deviation of the speed D And, where D - internal diameter

drum, which imposed photographic paper.

The direction of displacement is determined by the sign at Al, as well as the angle of the displacement of the bands;

g T D "

In the case of historical stability, the Al values of the bands will graphically represent the function A ((t) (Fig. 5).

The change in the speed of the studied part in the area between /

a turn and i + 1 turn of Al; --- YES (/ j + i; -; YES can be measured with an accuracy of 0.03 mm. At D. 600 mm, the ratio D "X 0.03" ,, rn,

on measurement accuracy - - 0,005%. When viziga -D 600

In general observation and approximate measurements, engine 9 is turned off, and matte tracing paper is fastened on the drum. On the tracing paper, as the shaft 6 rotates, light streaks located around the circumference will be visible.

With these strokes fixed, with Al and Al const, the light lines move in the same direction with a constant velocity,. G L1M. one

by the height of the V „I, determined by the use of a stopwatch.

L sec J

ge6 “GO 1

In this case - 1,

K D L min. J

With AL const, the bright streaks move in different directions at varying speeds. In a similar way, approximately the limits of Al and the frequency of changes in this value are determined.

The described device can also be used to measure the total kinematic error A ,. toothed meshing

in dynamic conditions

.OSO ,, ,, l. h

Lfe TU ()

degree, where X is the distance from a certain starting point of the line to the beginning or end of the line.

60- / ha

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