RU1772637C - Method of balancing with a laser beam - Google Patents

Abstract

The invention relates to instrumentation technology. The purpose of the invention is to improve the accuracy and performance of balancing. Prior to balancing, laser pulses of different energies are generated, the radiation power distribution is recorded during each generation pulse, the phase shift relative to the start of generation is determined, and it is taken into account when generating laser pulses in correcting the imbalance. 5 silt, 2 tablets

Description

The invention relates to instrumentation technology and can be used to balance gyroscopes rotating at an operating speed of rotation by a laser beam.

The aim of the invention is to increase accuracy and productivity, as well as to ensure the convergence of the balancing process.

Figure 1 shows a diagram of the formation of the angular error of the correction of imbalances by a laser beam; Fig. 2 shows a typical distribution of the power density of a laser radiation over a pulse duration, and also illustrates a technique for determining the required laser pulse time based on an equality of energies; Fig. 3 is a diagram for measuring a laser pulse duration; figure 4 presents a structural diagram illustrating the implementation of the proposed method for correcting imbalances

a laser beam; figure 5 presents photographs of the shape of the laser pulses LTU Quantum-16 (see table 1).

The rotor 1 is mounted in a correction device and accelerated to a balancing frequency. The vibration of the rotor is sensed by the vibration sensor 2 and converted into an electrical signal with a frequency equal to the rotational speed of the rotor and an amplitude proportional to the amount of imbalance. The indicated electrical signal is fed to the input of the imbalance parameter determination unit 3, and pulses from the photo-optical sensor 4, which receives a light contrast mark on the rotor surface, are fed to the second input. At the output of block 3, two electrical signals are generated - in the form of a constant voltage level proportional to the imbalance that controls the pump voltage of the laser 5, and therefore the pulse-generated signal energy, the back of which carries information about the passage of the same (L

WITH

sj

YU

oh co

4

logo in the focus of the laser optical system.

This pulse signal is fed to the input of the waiting generator 6, where it is delayed by the time T3 Tob, where T0b is the time of one revolution of the rotor. The signal from the output of the standby generator 6 is fed to the laser control unit 5, which initiates the generation of a pulse.

Let us determine the lead time of the start of laser pulse generation. Assuming that the mass being corrected m is proportional to the laser pulse energy W and the laser pump voltage U, we can write:

 -U,

(4)

or

T

 mk K / q (g, U) dr

(5)

When correcting the imbalance of a rotating body with a stationary laser beam:

P

Dk R 2 mi, (6)

i 1

where R is the radius of correction,

(p-t is the angle of the i-th corrected mass, or

Dk R m. cos, (7)

where mЈ is the total mass removed per pulse,

Ay is the reduced correction angle tg corresponding to the angular error, see Fig. 1.

In view of (5), expression (7) takes the form:

0

5

0

5

0

5

In this case, the removed masses mi (Wi) and m2 (W2) are equal to each other, and Д 2 лтх f is the correction angle ms, i.e., the angle error of the unbalance correction (where f is the balancing frequency).

The moment of time gx we determine the outcome of the condition of equality of energies

W1-W2.

then

/ q (r, U) dT / q (r, U) dr, (8)

ogh

After approximating the shape of the laser pulse by a function of the form q (U, f) and calculating certain integrals in expression (8), the time rx is determined.

As an example of practical implementation, let us determine the time for a Quantum-16 laser operating in the free-running mode with parallel-coordinated switching on of the discharge circuit inductors.

To this end, the shapes of laser pulses were experimentally determined (in accordance with the diagram of FIG. 3), photographs of which are presented in FIG. 5. The parameters of laser pulses are summarized in table 1.

In Table 2, we summarize the numerical data qi and g, depending on U (see Fig. §).

The conducted multivariate regression analysis using the least squares method with checking the adequacy of the created model allowed us to obtain the following dependence:

 L3i 5

q (T, U) 0.16TU + 0.15Ur + 0.5rU +

+ 3r-0.028rU-1.02rU-0.163.

(9)

 / q (r, U) d rcos D (p.

about

We determine the angular error of the correction of the imbalance D outcome from the condition that the magnitude of the removed masses before and after the angle L. p is equal to each other. To do this, we find such a moment in time tx (see Fig. 2) at which the energy Wi and L / 2 are equal under the condition:

WЈ Wi + W2,

where Wz is the total energy of the laser pulse.

It can be put with a high degree of accuracy that

GH00

/ q (r, U) dr / q (r, U) dr о Гх

 / q (r, U) dr, Zx

or

62z352

0.032r U + 0.15Ur + 0.186r U + 0.75r-0, 007t U-0.34T U-0.163 5.7611+

+ 6.25211-0.89611-0.3264,

where, for each value of U, tx can be determined.

For example, for, 8 (drive voltage B) is determined from the equation:

0,01037th -0,73 Th + 2,186 gh +

+ 0.75 gx-0.163th 2.78533,

where is tx 1.1 ms.

Thus, for any value of the voltage of the laser storage ring U, it is possible to determine the required time Tx ahead of the start of the generation of the laser pulse of the passage of the rotor's heavy spot at the focus of the laser optical system.

Claims (1)

SUMMARY OF THE INVENTION A method for balancing a laser beam by rotating a rotor, measuring the magnitude and angle of imbalance in instantaneous value of the laser pulse power density q; 10 fifteen twenty correction planes, combine the focus of the optical system of the laser with the correction plane and correct the imbalance, generating laser pulses, the energy of which is controlled depending on the imbalance, characterized in that, in order to improve accuracy and performance, they generate laser pulses with a time advance relative to the passage a desired place in the focus of the optical system by the quantity gx, determined for a specific laser pulse, starting from the condition that the energies of the initial and final n generation pulse tin: TX00 J qi (TJ, T) dT / qi (V, T) dr, oTx where qi (lT, t) is the power of the laser pulse; 1G - pump voltage; t is the duration of the laser pulse. Table 1 Table 2 IU Riga d l№) Fig g F / g J FIG. 4 "-. .. h "F . . F: /