SU1613500A1 - Method of stabilizing component dimensions by vibration - Google Patents

Abstract

The invention relates to mechanical engineering and, in particular, can be used for machining cast and welded parts to stabilize their dimensions. The goal is to increase the performance of vibration treatment and the quality of stabilization by reducing the time of vibration processing and reducing the error in monitoring its results. Vibration processing is performed by cyclically increasing and decreasing the frequency of vibration with finding effective values of the variable component of phase shifts, which determine the nature of controlling the rate of increase of the frequency of vibration during each cycle, while the vibration processing cycles are performed until the integral value becomes less permissible or not stabilized. 1 hp f-ly, 2 ill.

Description

The invention relates to the field of mechanical engineering and, in particular, can be used for machining cast and welded parts in order to stabilize their size.

 The invention is to increase the vibration processing performance and the quality of stabilization of parts by reducing the vibration processing time and reducing the error in monitoring its results.

Figure 1 shows the block diagram of the method; in fig. 2 shows an embodiment of a phase-measuring unit.

The block diagram (Fig. 1) contains the workpiece 1, laid on elastic supports 2, mounted on part 1 vibrator 3 with drive 4, control unit 5, regulating the vibration frequency, sensor 6 measuring the interaction force of vibrator 3 with part 1, frequency dependent amplifiers 7 and 8, phase-measuring unit 9, detector 10, unit 11 for determining the effective value of the measured parameter: adder 12, two-level frequency meter 13, key 14, integrator 15 and block 16 logical comparison. One of the possible options for block 9 (Fig. 2) contains one-shot 17 and 18 trigger 19 with two stable states and an inertial element 20, the time constant of which is approximately ten periods of the fundamental frequency of vibration.

The implementation of the method is carried out as follows.

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At the start signal, drive A is drawn and the start-ups increase in frequency 1 zibras1i, the rate of increase in frequency is set by the voltage U | An adder 12. The signal of the sensor 6 is fed to the inputs of two amplifiers 7 and 8, one of which, amplifier 7, performs the functions of a false-frequency filter, and the second, amplifier 8, a high-pass filter, so that at the output of amplifier 7, high-frequency The components of the measured signal are amplified at the output of amplifier 8. Signals from the outputs of both amplifiers are fed to the inputs of 17 o 18 vibrators of block 9. At that moment, when the potential value of the signals from the single vibrators 17 and 18 exceeds the preset level (which ry, in particular, is 0), on their outputs, amplitudes of the same magnitude and and versa appear, the mutual initial phase of which depends on the amplitude of the n phase of the high-frequency monics in the output signal. Amplifier 8. These Fg-a1l sy arrive at Fia trigger input 19, as a result of which its sequence generates a pulse sequence, the width of each of which is equal to the magnitude of the phase shift between JI resident in (the fronts of the ictulums at trigger trigger 19, first harmonic (signal at the output of amplifier 7) and a signal at the output of amplifier I, which contains the high-frequency harmonics of the power signal measured by sensor 6. Iner1CIon element 20It indicates the average value of the area of pulses over the following period. The frequency harmonics measured by the sensor 6 of the power signal are multiples of the vibration frequency, i.e. the first harmonic of this signal, the output signal of block 9 will be equal to a constant value (see Fig. 2), which is determined by the fraction of high-frequency components at the output of amplifier 8 the initial harmonics c. If the high-frequency harmonics in the composition of the power signal are transient, i.e., if they vary in time in phase with respect to the first harmonic, then the output signal of block 9 shows a variable component, which is detected by detector 10, and bl ok 11, being an inertial element, the effective value of this composition

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. The signal from the output of block 11 is sent to the second input of the adder, where it is added to the U value (and control of the rate of change of the pibration frequency, according to which, as the output signal of the block 11 decreases, the rate of growth of the frequency of rotation of the vibrator 3 decreases. substitution / hp -HUi-M, an increase is obtained for -; those - 1 vibro-processing at those frequencies at which the measured effective value of the Cr-. output signal of the unit 11) increases, i.e. at frequencies of the greatest impact of vibration on the part material.

The first harmonic from the output of amplifier 7 is also fed to the input of meter 13. The output of this meter is constant magnitude signals (1), which occur but reach the initial frequency of vibration processing f ,, and the maximum frequency specified by the setpoint U and U.

When the minimum frequency is reached, KFUCH 14 triggers a short circuit and the integrator 15 starts summing} the output signal. Of the block 1 1. The output of the integrator 15 is fed to the input of the logical comparison unit 16, in which, when the upper pre-j; ejia reaches the frequency f o (kc, the output signal of the integrator 15 is compared with the allowable value of 1 f. If at the vibration frequency the output signal of the integrator 15 turns out to be less or equal to the allowable value, at the output of the block 16, the Vits signal to stop the vibro-processing of the part, in accordance with which the drive 4 is disconnected; if the output signal of the integrator 15 exceeds U, then at the output of the block 16, The unit 16 provides a count of nlcls, which gives a signal to stop the vibration processing when, however, after the expiration of a specified number, the integral characteristic at the output of the integrator 15 does not decrease to the third faem At the output of b; 1ka 16, a VPS signal, indicating 1) 1 | need to repeat the processing of this part

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after aging for several days or the need to use another, non-vibrational way of stabilizing the dimensions of the parts.

The application of the invention makes it possible to shorten the time of vibro-processing of the part due to the fact that the processing time carried out at each of the stages at which the greatest impact is ensured depends on the value of the controlled effective value, and the resulting value of the integral, which characterizes the stability of the part, is compared with the acceptable value reaching the upper frequency limit. This eliminates the danger of deterioration in the stability of the part due to the excessive duration of the vibration treatment. An increase in the measurement sensitivity is achieved due to the fact that the integral value depends not only on the level of the effective value of phase fluctuations, but also on the integration time, which itself changes inversely proportional to the magnitude of these effective values, i.e. it is as if the dependence of the integral on the integrable parameter is quadratic. Improving the reliability of the method is achieved by eliminating a clock sensor and measuring fluctuations in the phase shift between the high-frequency and low-frequency components of the signal from one of the same force sensor. The minimization of the time of vibro-processing and the increase in the sensitivity of the control ensure a better quality of stabilization. The method makes it possible to programmatically control the vibration stabilization process. Due to the increased objectivity of the assessment of the stability control results, this method can also be applied in the processing of machine parts of high and high accuracy instead of the previously used hard and energy-intensive methods of natural and thermal aging.

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Claims (2)

Claim 1. Method of vibrating stabilization of part dimensions, including their vibro-processing with a vibrator, determining the optimum vibration frequencies providing the greatest impact, and monitoring the results of vibro-processing by means of vibrational analysis, in order to increase the vibro-processing performance and quality of stabilization details by reducing the time of vibro-processing and reducing the 15 error of control of its results, Vibration processing is carried out by cyclically varying the frequency of the vibration, while in the process of increasing it, the force acting on the part from the vibrator is measured continuously, high-frequency harmony is extracted from the signal, and the high-frequency harmonic phase is measured from - 25 harmonics of the power signal, inject the variable component of the measured phase shifts, determine the effective value of this variable component and regulate the speed 30 of increasing the vibration frequency in The cycle is inversely proportional to the effective value of this variable component, and the measured effective value is integrated over the entire frequency range of the vibration frequency, and when the upper frequency limit is reached, the value of the resulting integral is compared with the permissible, specified by the technology, 0 ° and then the frequency is reduced vibrations to its lower limit and begin the next cycle of frequency change, repeat the vibro-processing until the integral value becomes less than the allowable one given technology, or not stabilized. 2. The method according to claim 1, characterized in that the limits of the cyclic variation of the vibration frequency are 35 five From each condition, Q Q tanganp are at least three maxima of the effective values of the controlled phase shifts in each cycle. "Tvi spz- 4xj "