SU714456A1 - Photoelectric shaft angular position-to-code converter - Google Patents

Description

(54) PHOTO-ELECTRIC CONVERTER OF ANGLE OF SHAFT BARCHES CODE

The proposed invention relates to the field of instrumentation technology and can be used in optomechanical goniometer us-octbax for determining the coordinates of explored objects. Various constructions of transducers are known, which are used, for example, in metal-cutting CTatocax, in high-precision measuring devices, etc. Converters of angle to code with phase shifters are known, the principle of action of which is to measure the time interval corresponding to the phase difference between the reference voltage and the high voltage of the phase shifter, which is filled with the stabilizer frequency from the pulse generator. The error of this pr | og; the rapper depends on the linearity of the omorphic phase of the ph;; The indicated components influence the accuracy of measurement of angles, which are within ± 24-3 11. The limestone also includes an optical raster a tuning fork sensor containing a rotating drum with slots, a raster grill mounted on a ring tuning fork, a tuning fork drive, an illuminator and a photodetector1- hook The radiation from the illuminator, located on the inner side of the drum, passes through the dripping raster grating, cut through the drum and enters the photoperformer SC, located on the outer side of the drum. This sensor design improves the accuracy of angle measurement due to the constant operation of the grid on the resonant frequency and which does not have an axial beat, however, this sensor does not give a share about the catch position of the shaft in a cop form, and therefore does not have 1. used for static C2X angle angles; The photoelectric impu is well known; a;

discs rotating on opposite sides of the np03ffa4Htix with opaque risks applied to them, and located on either side of them, respectively, the photoreceivers and the radiation sources. At the moment of coincidence on the TeMfffltx disks, the risoxvet from the radiation source hits the photodetector, and at the time of the coincidence of the transparent and opaque, the light does not enter. This design also improves the accuracy of angle measurement, but does not provide a code combination of Szl signals.

The closest in technical essence to the proposed invention is a modifier with a multi-modular modulator that converts the angular positions of the shaft into electric pulses with a codification of them.

This converter contains an opaque rotating disk (drum) with slits, which are grouped into ring tracks, forming a code mask and fixedly mounted sensors consisting of a radiation source, orifice plate. if the receiver C4.

This transducer can be used as a whole in other cases, however, its use for determining angles of the order of, {for example, one angular minute and less is not possible due to the ore manufacturing of code drums in which the slots of lower code tracks with such discreteness hundredths of millimeters. Installing drums with such discreteness at nodes operating at medium speeds (up to 1000 rpm) requires the use of special cel-inertial photodetectors that have low durability. Narrow on the drum is easily contaminated, which reduces the reliability of the conversion.

The purpose of the invention is to increase the speed and resolution of the converter.

The goal is achieved by adding additional sensors to the photoelectric converter of the angle of rotation of the shaft and placing the groups along with the least significant number of sensors in the subsequent group equal to twice the number of sensors of the previous group, the first sensors in each group are installed Multiple integer number of steps between through proregz of the code element,

and the sensors inside each group are placed in such a way that the projections of the neck are on a plane perpendicular to the optical axis of the sensor, which is two times smaller than in the previous group.

Pa of the drawing shows a code element (drum), 1, having one track with uniformly applied slits, and three groups of sensors. Each sensor

includes illuminator 2, diaphragms 3 and 4, and a photodetector 5. Sensors and a drum are installed in a fixed case 6. When the drum is rotated, the converter outputs a signal combination

binary code, and in our case replaces the three-track code converter.

The width of the slots of the single-track drum and their number fully correspond to the older track of the three-track drum. The number of sensors in a group is selected by doubling the number of sensors in the previous group, i.e. just as the number of slots of the code drum is selected.

So p g where n is the number of sensors in the group,

2 is the group serial number. For example, for the third group the number of sensors. 4. The width of the slots $ 2. on the drum for each group of sensors must be equal to the width of the slots on the respective tracks of the prototype. Getting cracks given

It is provided by installing the sensors at appropriate c / i angles. (see drawing). (X. 7 are the angles formed by the intersection of the optical axes of the sensors with tangents whose vertices

Lelsat on the outer part of the drum.

With this installation of sensors, the width of the slots of the drum, capable of transmitting the luminous flux, decreases depending on

of the angle a (.. This width of the slits for each group of sensors is calculated by the formula; Sz

z 1

where S- is the width of the slots np drum. In the design for obtaining aadannoy width of the slots S,

sensors need to be installed at angles

s

o.arctg- | -arc5.n p.

where is the drum wall thickness.

In order to obtain a code combination with a converter with a single orbital band bank, patches in the group are set at an equal distance from each other or at distance m from the first sensor, which is determined by the shape of / i;

r.;,. t. ()) + (i: dll,

where K is any integer.

t is the spacing between the slots of the modulator, I is the sequence number of the sensor in

group.

The first rpyrin sensors are mounted at a distance M from each other, which is a multiple of the integer number of steps between the slots of the drum M - t K

During one revolution of the modulator, each sensor generates an equal Number of pulses, corresponding to the number of drum slots or the number of cfapmeft slots of the device's track - just the type that is not shown in the drawing, i.e. Each sensor operates with equal and minimum frequency of signal following, unlike sensors of a known device, operating with a different frequency of signal following, which doubles in the direction from the upper track to the lower one.

This conversion compared to the known increases the speed by reducing the frequency of modulation of the photodetector, as well as increases the resolution by performing the functions of the lower drum tracks by the older ones, reduces the size by reducing the number of slots on the tracks, the drum simplifies the technology and reduces by 10-15 times the manufacture of the drum and 20-25 times eix) opportunity.

Claims (4)

1. Ahmet Zhanov A. And. Systems of the transmission of the angle of increased accuracy ML, Energie, 1966 p. 9O. 2. Authors certificate of SUSR N9302594, O2 B 11/20, 1971. 3. USSR author's certificate number 302594, cl. q 01 B 11/26, 1968. - 4. Litvak V. I, Photoelectric sensors in control systems of control and regulation, Moscow, Science, 1966, p. 185-189, rice, 4.18 and 4.29 (prototype).