SU1472760A1 - Device for non-contact measurements of part dimensions - Google Patents

Abstract

This invention relates to instrumentation technology. The purpose of the invention is to increase productivity by eliminating the stopping of a part in the process of its positioning. The device contains a channel for changing the angle of rotation of the monitored surface, consisting of a semitransparent mirror 4, a beam-splitting prism 11, photodetectors 12 and 13, and a comparator 17, as well as an electronic key 21. When the monitored surface reaches the required angle of rotation, the comparator 17 issues an enable signal to the electronic key 21 .1 il.

Description

The invention relates to a measurement technique and can be used to control the dimensions of parts with curved surfaces.

The purpose of the invention is the reduction of measurement time due to exclusion in the process of its positioning,

The drawing shows the block cxc-jg ma device.

The device consists of a light source 1, a lens 2, optically coupled to a source 15 in series, translucent jg mirrors 3-6 mounted, a collimator 7 mounted between the mirrors 4 and 5, apertures 8-10, and aperture 8 located in front of the focal plane of the optical system, educated. 2ΰ by the collimator 7 and the mirror 5, the diaphragm 9 — behind the focal plane of the optical system formed by the collimator 7 and the mirror 6, and the diaphragm 10 — in the focal plane of the collimator 25 7, the beam-splitting prism 11., optically coupled to the mirror 4, of photodetectors 12.and 13, optically coupled to the prism 11, photodetectors 14-16 mounted behind the diaphragms 8-10, respectively, comparators 17-19, the inputs of the comparator 17 are connected to the outputs of the photodetectors 12 and 13, and the comparator 18 to the outputs of the photodetectors 14 and 15 , source .... 20 reference voltage, input and 19 are connected to the outputs of photodetector 16 and the source 20 and the electronic switches 21 and 22 'of the electronic key 21 inputs connected to the outputs _T d. comparators 17 and 19, and the inputs of the electronic key 22 to the outputs of the electronic key 21 and the comparator 18, the Measured part 23 is placed on the supporting surface 24 and has a reflection - ₍ , female surface 25, Moreover, such elements of the device as a translucent mirror 3, a collimator 7, a diaphragm 10, a photodetector 16, a cmparator 19 and a reference voltage source 20 form the first optoelectronic channel, and elements such as a pair of translucent mirrors 5 and 6 with apertures 8 and 9, photodetectors and 15 and a comparator 18 form .... the second channel, the third channel is formed by the floor a transparent mirror 4, a beam splitting prism 11, light detectors 12 and 13, and a comparator 17.

The device operates as follows.

Parts 2.3 make a translational * * movement along the supporting surface 24 "The optical radiation signal from source 1 through a translucent mirror 3 and lens 2 is sent to the controlled surface 25 of part 23" The optical signal reflected from surface 25 is collimated by lens 2 and sent by the translucent mirror 3 to translucent mirror 4, passing through which, part of the luminous flux falls on the beam-splitting prism 11, and the other part of the flux falls on the collimator 7 and then on to the translucent mirrors 5 and 6, reflecting b) from which part of the flow passes through the diaphragms 8 and 5, respectively, and acts on the photodetectors 14 and 15, and the electrical signals generated by them are fed to the inputs of the comparator 18, while if the controlled surface 25 is precisely in the focus of lens 2 ... due to the appropriate installation of the aperture 8 and 9 on the light pickups | 4 and 15 receive 'equal light' streams. And, accordingly, a zero signal is removed from the comparator 18.

When the reflecting surface 25 is shifted to the side relative to the focus of the lens 2, the light flux incident on the photodetector 14 and 15 will be different, and a signal proportional to the bias appears at the output of the comparator 18, the polarity of the signal depends on the direction of the bias. Since the diaphragm 10 is installed in the focus of the collimator 7, the maximum luminous flux passes through it to the light detector 16 (it reaches its maximum value when the reflecting surface 25 is located. Exactly in the focus of the lens 2). When the surface 25 is shifted to the side relative to the focus of the lens 2, the signal Of, taken from the light detector 16, decreases. in proportion to the amount of mixing. The value of U _(A at the output of the reference voltage source 20 is set so that the condition U g U _{p is} satisfied in the area where the relationship between the offset of the reflecting surface 25 relative to the focus of the lens 2 and the signal at the output of the comparison unit 18 is linear. If the condition Όφ 7 / U _n if the comparator 19 gives an enable signal, the second part of the stream separated by a semitransparent mirror 4 is divided into two parts by a prism 11 and enters the light detectors 12 and 13.

In the case when the normal to the surface 25 does not coincide with the optical axis of the lens 2, there is a spatial uneven distribution of the power of light radiation in different halves of the light flux reflected from the respective faces 15 of the beam splitting prism 11 that hits the photodetectors 12 and 13, which provide signals of unequal level falling into the comparator 17. Then, a signal prohibiting the passage of the enable signal through the electronic signal is received at the control input 20 of the electronic key 21 from the output of the comparator 17 key 21,

At the time when the normal 25 to the surface 25 of the part 23 coincides with the optical axis of the lens 2, the same luminous flux arrives at the photodetectors 12 and 13 and equal signals arrive at the comparator 17 from them. Under this condition, the electronic key 21 is open, an enable signal from the comparator 19 passes to the control input of the electronic key 22, ’a measuring signal 35 appears at the output of the device.

Claims (1)

Claim A device for non-contact measurement of parts containing a light source, a lens optically coupled to a light source, a collimator optically coupled to the lens, a first optical-electronic channel .. made in the form of a diaphragm located in the focal plane of the collimator, photodetector ^ a, located behind the diaphragm and, the comparator, the second optoelectronic channel made in the form of two translucent mirrors placed between the collimator and the diaphragm of the first channel, two diaphragms optically connected with half crab mirrors, first aperture! ' installed in front and the second behind the focal planes of the collimator, two photodetectors located behind the diaphragms, and a comparator, the inputs of which are connected to the outputs of the photodetectors, and an electronic key, the first input of which is connected to the output of the comparator of the second channel, characterized in that, in order to increase performance, it is equipped with a third optoelectronic channel, made in the form of a translucent mirror placed between the lens and the collimator, a beam splitting prism, optically coupled to a translucent mirror Ohm, two photodetectors, optically connected with a beam splitting prism, and a comparator, the inputs of which are connected to the outputs of the photodetectors, and a second electronic key, the inputs of which are connected to the comparators of the first and third optoelectronic channels, and the output to the second input of the first electronic key.