SU1458706A1 - Photoelectric converter of displacement into signal phase - Google Patents

Description

The invention relates to measuring equipment. The purpose of the invention is improving the accuracy - achieved by eliminating errors in reproducing

the study of signals of complex shape through the use of electrical phase modulation. The raster 4 is illuminated by a parallel light beam produced by the illuminator consisting of the radiation source 1, the condenser 2 and the semitransparent mirror 3. The raster image is projected by the lens 5 into the plane of the multi-element radiation receiver 6, which is gated by signals of the ring shift register 8. Signals are received alternately at the input of the sum amplifier. from several elements of the receiver 6. The phase of the resulting signal at the output of the amplifier 11 is proportional to the position of the raster 4. 2 Il.

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1458706

4The invention relates to measurement technology and can be used in software control systems for metal-cutting machines in geodetic instruments and other systems.

The purpose of the invention is to improve accuracy.

This goal is achieved by ed eliminating errors in reproducing signals of complex shape by using electrical phase modulation.

In Fig.1 shows a block diagram of the 'ed-ed toelectric transducer displacements in the phase of the signal; Fig. 2 are time diagrams explaining its operation.

Photoelectric transformation Tel ₂ 0 displacements in .fazu signal comprises an illumination system composed of radiation source 1, a capacitor 2 and the semitransparent mirror 3, a measuring screen 4, which consists of 25 alternating parallel grooves and is located in a parallel beam of rays, a lens 5, multi-element radiation receiver 6, made in the form of a ruler of η photo cells, each of which represents a strip, the size (width) is the same and less: an integer number (3 times or more) the width of the image of the stroke of the raster, η keys 7, an annular shift register 8 to which a generator of 9 rectangular pulses is connected, a frequency divider 10, a summing amplifier 11 and a smoothing filter 12. 4θ

Photoelectric transducer displacement in the phase of the signal works as follows.

Raster 4 is illuminated by a parallel beam of rays created by the illuminator. The raster image is projected by lens 5 into the plane of the multi-element radiation detector 6. This image has the form of alternating strips of equal width, with each strip $ θ overlapping at least three photocells of the radiation detector.

On figa shows one dark and one light band. With the number of photocell ruler equal to n = 8, ⁴

one lane overlaps four photocells. Assume that the bands are in position I (Fig. 2a) and the first four photocells are illuminated. In is

2

The current moment of time (1.1) is connected to the load with the first four photocells (the first four keys are open). As soon as the alternate impulse comes from generator 9 to the shift register 8, the keys 7 (second to fifth) open, resulting in the corresponding photocells of the radiation receiver 6 (position 1.2) being connected to the load and the signals will come from the second, third and fourth photocells , because the first photocell is not connected to the load, and the rest are not irradiated. After the next pulse from the generator 9, photo cells from the third to the sixth are connected. The signal U (s), taken from the load, will have the form of steps, and its initial phase is dependent on the measuring position of the raster 4. Thus, when moving stroke image on a first photocell (position II nafig.2b) _h in the Optional signal change 360 / n, where η - the number of photocells in the line of the receiver 6 radiation.

The step measuring signal is smoothed by the filter 12 and is compared in phase with the reference signal and _O p formed from the clock pulses by the frequency divider 10.

The phase of the smoothed measuring signal linearly depends on the position of the measuring raster. Since when the raster image is moved from position I to position II, the signal from the fifth photocell of the ruler will linearly increase, the signal from the first photocell of the ruler will linearly decrease according to the same law.

Claims (2)

Claim· A photoelectric transducer for moving to a signal phase containing an optically coupled illuminator system, a measuring raster, a lens and a multi-element radiation receiver made in the form of a ruler of η photo cells, η keys, a summing amplifier, a ring shift register and a square wave generator, η keys are used for alternating p & d- switches on the outputs η of the photocells to the corresponding η inputs of the summing amplifier, control inputs of the keys 1458706 connected to the corresponding outputs of the ring shift register, the input of which is connected to the output of the necator of rectangular pulses, characterized in that, in order to increase accuracy, he provides wives frequency divider and smoothing the filter, the input of which is connected to the output of the summing amplifier, the input of the frequency divider is connected to the output of the rectangular pulse generator, the photo cells are made in the form of strips oriented in the direction of the raster lines. I I. 3 g 1 LWG v.7 ι ι umt / m \\\ FIG. 2 &