SU397771A1 - VIBROMETER - Google Patents

Description

The invention relates to the field of vibration measurement and is intended to record vibrations and vibrations of machines, mechanisms, vibro-latforms and building structures.

The known oscillation detection devices are Inertia. They contain an inertial mass, which is fixed to a fixed body with the help of springs. As a result, the vibrometers register with unsteady and transient oscillatory processes (vibrations with varying frequency; and ami- litude).

In the proposed non-inertia-type vibrometer with the aim of increasing accuracy and reliability} of device operation, the converter element is designed as a double-sided disk head.

FIG. a diagram of the proposed vibrometer; in fig. 2 - the principle of action; vibrometer works.

The vibrometer contains a transducer element from a light two-track m-accessory: a chat disk head 1 with axis 2, in the center of which is fixed a mirror 3 with a long-focus lens 4. The head is pressed in two needle bearings of a. External bearing volumes 5 are rigidly connected to the head cover 6. The recording part of the Instrument consists of a condenser with an illuminator 7 and a cylindrical lens S, assembled in housing 9 of a tape-testing mechanism 10 with a motor) 1 cassette with receiving and feeding coils for photographic film (or photographic paper).

To record the vibrations, the vibrometer is attached using the device // to the fixed support so that the disk head / is pressed tightly by some kind of vibration to the object 12.

When the vibrometer object golo5ka oscillates, rolling around on its surface, makes rotational returning-postunitive dz} 1zh; 1 fully correspond; with amplitude, shape; oscillation frequency of the object. This mirror, fixed on the center of the axis of the head, rotates certain angles, the magnitude of which is also the projection} 1a amplitude of oscillations. A ray of light from the illuminator through the lyse - hits the nl mirror 3 and reflects on the photo paper, focusing first on the 1 point S. Reflected beam from the mirror c; i.e. forms a paper if there is no oscillation of the object or dashes. leriendik rio axis axis of the head, gfi presence; oscillations, as mirror mirrors cause the deflection of the reflected beam 1 of the light n t) 1 a y. photo paper.

The length of the received line (recording amplitude) and the length of the reflection of the light beam (the length of the optical lever) is directly proportional to the angle of the mirror's turn (Fig 2). At a constant beam length, the recording amplitude depends only on the angle of rotation of the mirror. To scan the oscillatory process in time, the photo paper is propelled at a constant speed with the help of a ribbon-like mechanism.

Since the coefficient of increase and sensitivity (sensitivity) of the choice is the value of the ratio of the amplitude at the output of the device (at the photo tape) to the amplitude at the output (amplitude of the object's oscillations), the increase in the vibrometer depends on the length of the optical lever and the angle turning the mirror. The angle depends on the diameter of the disk head. The smaller the diameter of the head, the larger the angle of the mirror with the same amplitude due to the oscillations of the target.

The magnification factor can be determined but the known. M. Par. Meters of the structural elements of the device using the following formulas (Fig. 2):

,(one)

but

where 1 is the coefficient of increase of the device; L is the width of photo tape; and - the amplitude of the object;

An entrant may be underwritten

BSYU width photo-foils; C K

(2)

a +

With HP - the length of the circumference of the head; d-head diameter;

four

Kggg

D is the deflection angle of the mirror;

L / 2

S 2sin

(four)

Z is the length of the beam.

To expand the range of amplitudes of the recorded oscillations, the disk scuffer has several stages of diameters. In addition, the head itself is volumetric and can be replaced with another one with any necessary diameters. A change in the magnification can also be achieved by changing the different recording devices with different ontic levers.

The subject and s obretep

A vibrometer containing a converter element and a recording device consisting of a condenser with illuminator, a cylindrical lens and a tape mechanism with a motor and a cassette, characterized in that for the purpose of the device and its new accuracy and reliability, the converter is The element is made in the form of a two-sided multi-stage disk head pressed to a co-heading object, in the center of the axis of rotation of which is fixed a mirror with a liise.

FIG. 2