SU386241A1 - PHOTOELECTRIC DEVICE TO CONTROL THE QUALITY OF THE SURFACE OF HIGH-PRECISION DETAILS - Google Patents

Description

one

The invention relates to the field of measurement technology and can be used to control the quality of the surface of high-precision parts, for example, rolling elements and other bearing elements.

Photovoltaic devices are known to control the quality of the surface of high-precision parts, for example, rolling elements of bearings, which contain an optical-mechanical system, providing an inspection of the entire surface of the part being monitored at a constant speed, a photodetector reacting to changes in the reflected light from the part being monitored, a measuring unit, mounted at the output of the photodetector, and a control flap control unit.

In such devices, the measuring unit is made in the form of a temporary pulse selector coming from | a photodetector, which allows determining the extent of the defect on the surface of a part from the duration of these pulses.

A disadvantage of the known devices is that they do not control the depth and number of defects.

The proposed device differs from the known one in that it is equipped with a two-input element OR, the output of which is connected to a scrap gate control unit, the measuring unit is designed as an amplitude-time selector of the pulses of the photodetector and a selector of the number of these pulses that appear when inspecting a portion of the surface of a given length, moreover, one input of the element OR is connected to the output of the amplitude-time selector, and the other its input to the output of the selector of the number of pulses.

This allows you to control not only the extent of the defect, but also its depth, and the number of defects on the surface areas of the part, having their specified length, and therefore increases the reliability of quality control of the part surface.

FIG. 1 shows a block diagram of the proposed device; in fig. 2 - time diagram of his work.

The proposed device contains an optomechanical system that provides inspection of the entire surface of the test piece / at a constant speed and consists of a sweep unit 2, an illuminator 3, a receiving optical unit 4, a photodetector 5, an amplitude-time selector 6 of the pulses of a photodetector 5, a selector 7 of the number of pulses of the photoreceiver 5, appearing when inspecting the surface of a given extent, the two-input element “OR 8” and the reject flap control unit 9.

The photodetector 5 consists of a sensing element 10, for example a photodiode, and an amplifier 11.

The amplitude-time selector 6 contains, for example, a pulse amplitude comparator 12, Schmitt trigger 13, one-shot 14, element “And 15.

The selector 7 contains, for example, a Schmitt trigger 16, a one-shot 17, an AND 75 element, a binary counter consisting of I / 20 triggers, a valve 21 for returning the counter to zero.

The reject flap control unit 9 contains, for example, a trigger 22, a rejection flap actuator 23 controlled by a trigger 22, and a return cam 24 of the triggers 19, 20, 22.

One input of the element "OR 8" is connected to the output of the amplitude-time selector 6, and the other input of its element - to the output of the selector 7. The output of the element "OR 8 is connected to the defective flap control unit 9. The device works as follows. The optomechanical system, consisting of units 2, 3, 4, inspects the entire surface of the test piece. At the same time, the light beam sent by the illuminator 3 to each inspected point of the part surface is reflected from this point and through the receiving optical unit 4 enters the photodetector 5. The latter reacts to a change in the reflected light from the part and produces electrical pulses, the duration and amplitude of which characterizes, respectively, the extent and depth of the defect on the surface of the part /, and the number of these pulses is equal to the number of defects.

The voltage / output5 from the output of the photodetector 5, which characterizes these pulses, is fed to the inputs of the comparator 12 and the Schmitt trigger 13, which are part of the amplitude-time selector 6, as well as the input of the Schmitt trigger 16, which is part of the selector 7.

If the voltage {/ output5 exceeds the specified value f cpa6i2 in absolute value. corresponding to the permissible depth of the defect, the comparator 12 generates a series of pulses characterizing the change in the voltage C / EXIT at its output.

If the voltage / output exceeds in absolute value a certain threshold Uo necessary to measure the duration of the pulses of the photodetector 5, Schmitt triggers 13 and 16 are triggered, the output of which produces "rectangular pulses of voltage Uh, 16 / the duration of which corresponds to the duration of the pulses f / BMxs. From the leading edge of the Schmitt trigger pulses, a one-shot 14, a pulse TI, a voltage / voltage of a given duration, corresponding to the allowable length of the defect, is triggered. Element “And 15 retracts pulses from comparator 12 to its output (see voltage f / BHxis to

FIG. 2) only during the pause between the TI pulses coming from the single-oscillator 14, that is, only in the case when the pulse duration of the photodetector 5 exceeds the pulse duration. As a result, the pulses at the output of the element “And 15” correspond to defects whose length and depth exceed valid values. These pulses, through element 10 "OR 8, trigger trigger 22, which activates a rejection flap actuator 23, through which the part is sent / sent, for example, to a receiver of unusable parts. The change in output voltage output 22 trigger 22 is shown

15 in FIG. 2

From the leading edge of the voltage pulses t / Bbixi3.16, arising at the output of a Schmitt trigger 16, a one-shot 17 triggers, generating voltage pulses T2

20 t / Bbixi7 of a given duration, corresponding to a given length of the part surface at a constant speed of its inspection. The element & 18 transmits to its output the pulses from the output of the Schmitt trigger 16 arising during the existence of the pulses T2 generated by the single-oscillator 17.

The counter formed by the triggers 19, 20 performs the binary counting of the output pulses of the element "AND 18 by their forward

0 fronts. If the number of counted pulses is less than a specified number, in this example it is less than two, then the signal (7 out2 from the output 25 of the flip-flop 20 allows the opening of the valve 21, which is on the falling front

5 pulses Ta coming from the one-shot 17 returns the counter (triggers 19, 20) to the initial state. After counting a given number of pulses, a trigger 20 is triggered, at the output 2 € of which a voltage pulse 6out2.0 appears. This impulse by its leading edge through the element OR 8 turns on the trigger 22 and the flap actuator 23, as a result of which the part is sent to the scrap receiver. Simultaneously with this signal

5 t / Bbix2o from the outlet 25 prohibits the opening of the valve 21.

The surface of the part is monitored / performed by measurement cycles. At the end of each cycle, the cam 24 produces voltage / output pulses 24, which return the triggers 19, 20, 22 to the initial state. FIG. 2 shows cycles I, II, III, IV. In cycles I and III, the monitored surface areas have acceptable defects and therefore are considered

5 fit. In cycle II, the monitored surface area contains a defect that has unacceptable extent and depth. In cycle IV, the monitored surface area contains an unacceptable number of defects, 0 each of which has permissible extent and depth.

Subject invention

A photoelectric device for controlling the quality of high-precision ateli, such as rolling bodies and other bearing elements, containing an optomechanical system for inspecting the entire surface of the test piece at a constant speed, a photo detector that responds to changes in the reflected light reflected from the workpiece, "At the output of the photodetector, and a control flap control unit, characterized in that, in order to increase the reliability of the control, it is equipped with The "OR" output element, whose output is connected to the scrap gate control unit, is made up of a measuring unit in the form of an amplitude-time selector of photoreceiver pulses and a selector of the number of these impulses that appear when inspecting a portion of the surface of a given density, and one input of the OR element is connected with the output of the amplitude-time selector, and its other input - with the output of the selector number of pulses.

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