SU1733927A1 - Digital optoelectric displacement transducer for serial counting - Google Patents

Abstract

The invention relates to a control and measuring technique. The aim of the invention is to increase reliability and accuracy. On the path of the light pulses generated by the light source 2, there is a ruler 3, associated with the object, provided with slots made at a predetermined pitch. The light pulses are perceived by the photosensitive surfaces of the photodetectors 4 and 10 and are converted into electrical signals that undergo processing in the counting channel, which includes the first photodetector 4 connected in series, the shaping amplifier 5 and the D-flip-flop 6 and two elements And 7 and 9, and in the channel analyzing the direction of motion, which includes the second photodetectors 10, the amplifier-driver 11 and the D-flip-flop 12, and two differentiating circuits 13 and 15. A positive effect is achieved by the optimal choice of geometric parameters elements in the optical path of the sensor, thus reducing the minimum pitch line 3 and to reduce the number of required channels for processing from three to two. 2 Il. (Ls

Description

The invention relates to a measuring and control technique and can be used in telemetry systems for measuring linear displacements and coordinates of a monitored object with a linear displacement relative to the point at which motion begins.

The purpose of the invention is to increase the reliability and accuracy of the sensor.

This goal is achieved by the fact that a digital optoelectric sensor of linear displacements of sequential counting, containing a series-connected pulse generator and a source of light, a ruler connected to an object, are connected in series

photodetector, amplifier-shaper and D-flip-flop one-shot, whose input is connected to the second output of the generator, and the output is connected to the C-input of the D-flip-flop, two And elements, the first inputs of which are connected to the 0-output of the D-flip-flop, and a pulse counter, equipped with serially connected second photoreceiver, amplifier-shaper and D-trigger, the C input of which is connected to the output of the single vibrator, and two differentiating elements, the inputs of which are connected respectively to the Q and 0 outputs of the second D flip-flop with the second inputs of elements I.

VI

with

CJ

about

Yu

VI

The sensor operation is provided with the following ratios between the dimensions of the optical fibers and the slits of the ruler:

L D;

W L + D;

S 2Ш, where L is the distance between the axes of the optical fibers;

D is the diameter of the optical fibers;

W - the width of the slots in the line;

S - line pitch.

Fig. 1 shows a ruler and fibers of a radiation source and photodetectors with dimensions; figure 2 - structural diagram of the proposed linear displacement sensor.

The sensor contains a series-connected pulse generator 1 and a light source 2, a ruler 3, connected to the object, two channels: a counting channel, including a series-connected photodetector 4, amplifier-shaper 5, D-flip-flop 6, two two-input elements And 7 and 8 , the first inputs of which are connected to the O-exit of the D-flip-flop 6; the direction of motion analysis channel, which includes the second photodetector 10 connected in series, the amplifier-shaper 11, D-flip-flop 12 and two differentiating circuits 13 and 14, the first input of which is connected to the D-flip-flop 12, and the output to the second input of the first element I

7, the input of the second differentiating circuit 14 is connected to the O-output of the D-flip-flop 12, and the output is connected to the second input of the second element AND

8, the pulse counter 9, the first input of which is connected to the output of the first element And 7, and the second input connected to the output of the second element And 8, the one-shot 15, the input of which is connected to the second output of the pulse generator 1, and the output to the C inputs D-flip-flops 6 and 12.

Thus, to analyze the direction of movement of the ruler 3 associated with the object, the transition from the unlighted state of the second photodetector 10 to the illuminated state and vice versa is used. Wherein

(to unambiguously establish the correspondence between such transitions and the direction of motion), the sensor circuit and the necessary ratios between the dimensions of the light guides and slots in the line ensure that the input signals on the pulse counter appear only when the first photodetector is illuminated.

The advantages of the proposed sensor include the following. The number of processing channels is reduced from three to two, which increases the reliability of the sensor. The maximum possible accuracy of measuring the movement of an object increases by 1.5.

times, since the highest possible accuracy is determined by the minimum line spacing Smin for the proposed sensor Smin 2W 4D, for the prototype Srmn, f3 (W + D) s-6D.

Claims (1)

A digital optoelectric sensor for linear movements of sequential counting, containing a series-connected pulse generator and a light source, a ruler connected to an object, a series-connected photodetector, a booster and a D-flip-flop, a single-shot, whose input is connected to the second generator output, and the output is connected to the C-input of the D-flip-flop, two elements And, the first inputs of which are connected to the O-exit of the D-flip-flop, and a pulse counter, the inputs of which are connected respectively, with outputs of elements And, characterized in that, in order to increase reliability and accuracy, it is equipped with serially connected second photoreceiver, amplifier and D-trigger, whose C input is connected to the output of a single vibrator, and two differentiating elements, whose inputs are connected respectively to Q and Q outputs of the second D-flip-flop, and the outputs are connected respectively to the second inputs of the elements I. i fig L