SU504081A1 - Device for automatic detection of defects on internal surfaces of pipes - Google Patents

Description

The invention relates to a measurement technique, intended to control the quality of the manufacture of the internal surfaces of pipes.

A device for the automatic detection of defects on the inner surfaces of pipes is known, comprising an illuminator, a re-focused optical system, v; A lens in the form of a lens with a variable focal length, a photodetector unit, a scanning mechanism with an eccentric diaphragm, which ensured its rotation synchronously with the refocusing of the optical system and the observation channel.

The complex structure of the device and the comparatively low accuracy of the measurements are due to the fact that for synchronization of refocusing and circular scanning of the image, the refocusing mechanism of the object is controlled by nonlinear coaxiality with the scanning mechanism of the image. On top of that, there are difficulties in ensuring high productivity of work and equal precision in the determination of defects along the entire length of the complex.

That the lens creates in the plane of the analyzing diaphragm a varying image of a portion of the pipe surface. The known device also uses a powerful light source of the monitored tube.

The proposed device differs from the known one in that the optical system is made of two telescopic systems, such as Kepler optical tubes, and a micro-lens located between them, kinematically associated with a diaphragm configured to move along the optical axis of the device, so that its movement and rotation of the diaphragm obey the linear law, and the window of the diaphragm is made with a positivity exextristate relative to the axis of its rotation.

Such an embodiment of the device allows s; t to simplify the design and improve the accuracy of measurements.

The drawing is a diagram of the proposed device.

Claims (2)

The device is equipped with an illuminator l.ofnii.- ktiv 2 with an ocular 3, which make up the first telescopic system — o: Kepler's connecting tube; microscopic lens, best blush-gifted to its axial displacement after) ovative focusing image of an orthopedic surface, rotating lens, 1y 6, lens component 7, photo-lens, block 8, observable, formed by turning mirror 9, grid 10 and eye 11 , electric motor 12 and gearbox 13. Co..trap epp, 1st object (tube) 14 is placed between illuminator 1 and lens 2. The illuminator 1 directs the light flux to the inner surface of the test tube 14, the first telescopic system — the Kepler optical tube forms an intermediate image of a portion of the illuminated surface. B | 1 is an axially displaced micro-lens 4 that sequentially focuses images of the controlled surface, formed by lens 2 and school 3 of the first telescopic system. The micro lens directs a parallel beam of rays to the lens 5 of the second telephoto system, which forms an annular image of one or another surface area. 5. The size of the diaphragm window and its eccentricity: relative to the axis of rotation are kept constant for a given diameter, controlled by surface. Behind the diaphragm races,. A lens component 7 is placed, which, like an eye, creates a real image of the entrance pupil of the second optical tube, including components 5 and 7. Photoreception) The first block is located behind the lens section 7 so that the exit pupil of the second optical system is aligned with the photosensitive surface photodetector. If, when scanning an annular image of a surface area of a monitored pipe, the image of the defect npeBbt shifts the allowable value, then the light detector does not receive a light flux and does not detect the presence of a defect. The device is tuned with a visual channel, which consists of a turning mirror 9, a grid 10 and an eyepiece 11. I Moving the micro-lens 4 and rotating diaphragm 6 is carried out by an electric motor 12 through a gearbox 13. Formula for automatic detection of defects on internal surfaces tubes, the illuminator, the refocused optical system, the photodetector unit, the scanning mechanism with an eccentric diaphragm, which ensures its rotation synchronously with the refocusing (optical system, characterized by the fact that, with the aim of simplifying the design of the device and increasing the measurement accuracy, the optical system is made of two telescopic systems, such as Kepler optical tubes, and a micro-lens located between them, kinematically connected with the diaphragm and made along the optical axis of the device so that its movement and diaphragm (follow the lily law, the diaphragm window is made with a constant eccentricity relative to the axis of its rotation.