SU431126A1 - DEVICE FOR THE CONTROL OF NON-Parallelism of Glass Edge - Google Patents

Description

one

A device for monitoring the non-parallelism of glass faces is known, comprising a light source, a translucent plate mounted on the front side of the glass, a measuring unit for the position of the rear face of glass, the output of which is connected to a recording device through an adder, and a plane-parallel transparent plate mounted behind the rear face of the glass the axis of rotation of which is kinematically connected with a reversible motor.

However, the use of such a device in the process of vertical extrusion does not allow an increase in the accuracy of measurements, which is connected, first of all, with the inconsistency of the orientation of the glass faces with respect to the axis of the light beam. When the angle of incidence of the light beam changes to the front face, which can be caused not only by changing the direction of the wedge, but also by "playing glass, the refracted light beam experiences an offset, resulting in a measurement error.

The purpose of the invention is to improve the accuracy of measuring the parallelism of glass faces.

This is achieved in that the device is equipped with a block for correcting the position of the front face of the glass, the output of which is connected to the input of the adder.

FIG. 1 shows a block diagram of the described device; in fig. 2 is a diagram of the optical system; in fig. 3 - the cross section of the light beam emerging from the optical system.

The device contains a light source 1, an optical system 2, and a translucent plate 3. The measuring unit for the position of the rear face of the glass consists of a lens 4, a photodetector 5 and an electronic unit b, equipped with

band-pass filters 7 and 8, amplifier detectors 9 and 10, and the comparison circuit 11. The test glass 12 is located between the translucent plate and the measuring unit for the position of the rear face of the glass. Before

the lens has a plane-parallel transparent plastip 13, the axis of rotation of which is associated with a reversing motor 14 controlled by an amplifier 15. The output of the sensor 16 is the position of the motor shaft together

with the output of the correction block 17, the position of the front face of the glass through the adder 18 is connected to the recording device 19.

The optical system includes mirrors 20, capacitors 21, a reflective prism 22,

the edge 23 of which is located in the focal plane of the lens 24, and the luminous flux modulators 25 and 26.

The block for correcting the position of the front face of the glass is made in the form of a lens 27, a photo-detector 28, and an electronic unit 29 having

bandpass filters 30 and 31, similar to the electronic unit, amplifiers, detectors 32-33, as well as a correction converter 34.

The device works as follows.

The luminous flux of source 1 using mirrors 20 and condensers 21 is directed to a reflective prism 22, a passage through openings of disk modulators 25 and 26 rotating at different angular velocities.

The cross section of the light beam emerging from the lens 24 is divided into two equal parts by the image of the rib 23 of the prism 22. One of the beam parts is modulated by the frequency / 1, and the other by the frequency / 2 Part of the light flux, reflected from the front face of the glass 12, the semitransparent plate 3 is guided to the photodetector 28 of the correction unit 17. The remaining portion passes through the test glass 12 and is assembled on the photodetector 5 with a lens 4.

The photodetector is located so that in the absence of optical distortions the light fluxes falling on it, modulated by the frequencies / 1 and / 2, are equal (Fig. 3). The amplitudes of the signals fi and f2 allocated by the bandpass filters 7 and 8 at the output of the detector amplifiers 9 and 10 are equal. The algebraic sum of the signals at the output of the comparison circuit 11 is zero and the system is in equilibrium.

When a wedge defect appears in glass, the dividing line of two light fluxes due to refraction shifts. The amplitudes of the frequencies / 1 and / 2 become different in size and the output of the electronic unit 6 appears unbalance signal amplified by the amplifier 15. This signal controls the reversible motor 14, turning the plane-parallel transparent plate 13 until the imbalance is eliminated. The angle of rotation of the base plate is a function of the degree of non-parallelism of the edges of the glass and is recorded with the aid of a position sensor 16 by a recording device 19.

The red face position fixing unit determines the position of the front face of the glass 12 under study and, if the axis of the light beam is not perpendicular, generates a correction signal. The luminous flux reflected by the front edge of the glass is collected on the photodetector 28 by a lens 27. Moreover, if ne

If the edge is perpendicular to the axis of the light nugget, then the light fluxes of the frequencies i and / 2 falling on the photoreceiver are equal and the correction signal at the output of the corrective converter 34 is zero. At offset

the front face of the glass shifts the image of the dividing line of the light fluxes, which causes an inequality of the signals of the frequencies fi and / 2, separated by the bandpass filters 30 and 31, at the output of the amplifier-detectors 32 and 33.

Depending on the difference of these signals, the correction converter 34 generates a correction signal, which is fed to the input of the adder, where it is summed algebraically with the main signal coming from the sensor.

position 16.

The correction signal amends the measurement result and, thus, eliminates the error caused by inconsistency in the orientation of the front face of the glass relative to the axis of the light beam. The adjusted total signal is fed to the recording device 19, which gives information about the actual value of the non-parallelism of the glass faces.

Subject invention

A device for monitoring the non-parallelism of glass faces, containing a light source, a translucent plate mounted on the front side of the glass, a measuring unit for the position of the rear face of glass, the output of which through an adder is connected to a recording device, and a plane-parallel transparent plate mounted behind the rear face of the glass, axis rotation of which is kinematically connected to a reversible motor, characterized in that, in order to improve measurement accuracy, the device

equipped with a block for correcting the position of the front face of the glass, the output of which is connected to the input of the adder.

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FIG. one

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