RU2461797C1 - Device to measure bend of artillery barrel - Google Patents

Abstract

FIELD: weapons and ammunition.

SUBSTANCE: device to measure bend of an artillery barrel includes an angled three-edged reflector 9, a reflector lens 1, designed for location on the barrel end 2, and a metering unit 3 optically coupled with them, comprising a lens 7 and a photodetector 8, forming a receiving channel, and also an optical mark 5, installed between a radiator 4 and a beam splitter 6. The radiator 4 and the optical mark 5 form a light beam shaper. The beam splitter 6 couples optical axes of the light beam shaper and the receiving channel. A system 10 to generate images of an optical mark may be introduced into the composition of the metering unit 3. The reflector lens and the angled three-edged reflector may be arranged in the form of a single monoblock part from transparent material, on the output face of which there is a spherical surface.

EFFECT: higher accuracy of measurement under complicated operational conditions.

4 cl, 3 dwg

Description

The invention relates to instrumentation, in particular to devices for measuring the strain of long structures, for example artillery barrels of various lengths and calibers.

A device for controlling the bending of an artillery barrel [1]. This device comprises a light beam former located at the beginning of the barrel and directing the light beam along the barrel. A mirror is mounted at the end of the barrel, which reflects the light beam onto the photodetector of the photodetector. When the barrel bends, the mirror rotates, the reflected light beam is shifted relative to the photodetector. The magnitude of this bias is judged on the magnitude of the bending of the trunk. However, since the mirror is mounted at the end of the barrel, during the shot it experiences significant shock loads that affect the stability of the angular position of the mirror. In addition, the angular position of the mirror may depend on other external influences not related to the bending of the barrel, for example, on fluctuations in external temperature. Therefore, in such a device significant measurement errors occur, the measurement accuracy is small.

The closest in technical essence to the claimed invention is a device that implements a method for measuring the bend of an artillery barrel [2]. This device contains optically coupled reflector, aperture, and a photodetector containing an emitter, a beam splitter, a lens, and a photodetector. The lens and the photodetector form a photodetector channel, which is connected with the emitter using a beam splitter.

The emitter and the beam splitter are located in one housing with a photodetector channel, forming a measuring unit with it (photodetector sensor). The measuring unit is installed at the beginning of the barrel and directs the light beam along the barrel to the optical mark mounted on the end of the barrel. In the known device, such an optical brand is the diaphragm. Behind the diaphragm at the end of the barrel there is a reflector reflecting the light beam in the direction of the photodetector installed at the beginning of the barrel. Such a reflector can be an angular trihedral reflector (triple prism). The lens of the photodetector channel forms in the plane of the photodetector an image of the optical mark, which is the diaphragm mounted on the end of the barrel.

Bending the barrel leads to a linear displacement of the end of the barrel and, accordingly, to the displacement of the diaphragm. This linear displacement of the diaphragm leads to a displacement of the image of the diaphragm on the photodetector. The magnitude of this displacement determines the magnitude of the displacement of the diaphragm and taking into account the distance from the lens to the diaphragm, the magnitude of the bending of the barrel is determined. In this case, a change in the angular position of the diaphragm does not affect the measurement accuracy.

However, in such a device, in order to achieve the required accuracy of measuring the bending of the barrel, it is necessary to determine the position of the image of the diaphragm with an accuracy higher than the size of this image. Therefore, the accuracy of the measurement depends on the image quality of the diaphragm. At the same time, since the diaphragm is located at the end of the barrel, precipitation, dust, and dirt can fall on it during operation. These external influences can change the distribution of illumination in the image of the diaphragm and even change the geometric parameters of the image (if dirt gets on the diaphragm, the contour of the image may change). The image quality under these conditions deteriorates, the accuracy of determining the position of the image of the diaphragm in the plane of the photodetector decreases, and therefore, the accuracy of the measurement of bending is small.

The present invention is to improve the accuracy of measurements in difficult operating conditions.

To do this, in a device for measuring the bend of an artillery barrel, including an optically conjugated angular trihedral reflector, an optical mark and a measuring unit containing a lens and a photodetector forming a receiving channel, an emitter and a beam splitter, in contrast to the prototype, an optical mark is installed in the measuring block between the emitter and a beam splitter and forms a light beam shaper with the emitter, and a reflector lens is located in front of the corner trihedral reflector.

To further improve accuracy, the focal length of the reflector lens is equal to twice the distance from the optical mark of the light beam former to this lens.

Improving the accuracy of measuring the bending of the barrel during operation in difficult conditions is also ensured by introducing into the measuring unit an optical brand image forming system that is optically coupled to the lens and the photodetector of the receiving channel, while the focal length of the reflector lens is equal to twice the distance from the optical brand image to this lens .

The measurement accuracy under shock loads in the proposed device increases when the reflector lens and the angular trihedral reflector are made in the form of a single monoblock part made of transparent material, on the input face of which a spherical surface is made.

Figure 1 presents a diagram of a device for measuring the bend of an artillery barrel.

Figure 2 presents a diagram of a device for measuring the bending of an artillery barrel with an optical mark image forming system.

Figure 3 presents a diagram of a device for measuring the bending of an artillery barrel with an angular trihedral reflector and a reflector lens, made in the form of a single monoblock part.

The invention is illustrated in figures 1-3, where

1 - reflector lens;

2 - trunk;

3 - measuring unit;

4 - emitter;

5 - optical mark (diaphragm);

6 - a beam splitter;

7 - lens receiving channel;

8 - photodetector;

9 - angular trihedral reflector;

10 is an image forming system of an optical brand;

11 is an image of an optical mark;

12 - protective window of the measuring unit;

13 - angular trihedral reflector, made in conjunction with the reflector lens in the form of a single part.

The device for measuring the bend of an artillery barrel, shown in figure 1, includes an angular trihedral reflector 9 and a reflector lens 1, designed to be placed at the end of the barrel 2, and a measuring unit 3 optically coupled to them, designed to be placed at the beginning of the barrel 2. The measuring unit 3 contains a lens 7 and a photodetector 8, forming a receiving channel, as well as an optical mark 5 mounted between the emitter 4 and the beam splitter 6. The emitter 4 and the optical mark 5 form a light beam former. The beam splitter 6 mates the optical axis of the shaper of the light beam and the receiving channel.

When implementing the inventive device, the angular trihedral reflector 9 can be made in the form of three mutually perpendicular mirrors or triple prisms. As the photodetector 8, a CCD array or any other photodetector device can be used, the output signal of which depends on the coordinates of the image of the light beam incident on it. The reflector lens 1, mounted together with a corner triangular reflector 9 at the end of the barrel 2, can be made in the form of a single or glued lens from a material transparent to the light beam according to the technology usual for the optical industry. The beam splitter 6 can be made in the form of a plane-parallel plate of a transparent material (glass) with the application of a multilayer dielectric coating on its surface. Optical mark 5 may be a plane-parallel plate of glass or other transparent material for radiation, on the surface of which the necessary pattern is made by photolithography or by engraving. Optical mark 5 can also be made in the form of a diaphragm from a metal plate with one or more holes, the size and shape of which depend on the type of photodetector and the method for determining the position of the image in the plane of the photodetector.

Figure 2 shows the arrangement of the elements of the device when the optical marking system 10 is introduced into the measuring unit 3. The system for forming an image of an optical mark can be made in the form of a projection system, which is usual for optical instruments, in which the construction of the image 11 of the optical mark 5 is performed using, for example, a lens. The image 11 of the optical mark is located outside the measuring unit 3 with the protective window 12. The focal length of the lens of the reflector 1 located at the end of the barrel 2, in this case, is equal to twice the distance from the image 11 of the optical mark to this lens.

Figure 3 shows a device for measuring the bend of an artillery barrel with an angular trihedral reflector, made in conjunction with the reflector lens in the form of a single monoblock part 13 of transparent material, the input face of which has a spherical surface. Such a single part can be manufactured according to the technology of manufacturing triples-prisms and the technology of making spherical surfaces on optical parts, which is usual for the optical industry.

A device for measuring the bend of an artillery barrel works as follows.

When measuring the bend of the barrel 2, the image of the optical mark 5 is formed in the plane of the photodetector 8 using the lens of the reflector 1, the angular trihedral reflector 9 and the lens 7 of the receiving channel. When the barrel 2 is bent, its end is displaced, the reflector 1 lens and the angular trihedral reflector 9 are displaced. The displacement of these optical elements leads to the displacement of the image of the optical mark 5 in the plane of the photodetector 8. According to the magnitude of the displacement of the image of the optical mark 5, taking into account the foci of the lenses 1 and 7, determine the magnitude of the displacement of the lens of the reflector 1, that is, determine the magnitude of the displacement of the end of the barrel 2, which, taking into account the length of the barrel, serves as a measure of its bending.

In the claimed device, the position of the image of the optical mark 5 on the sensitive area of the photodetector 8 does not depend on the angular rotation of the lens of the reflector 1 and the angular trihedral reflector 9. This ensures the necessary accuracy of measuring the bending of the barrel under dynamic loads experienced by these optical elements during firing. Since the optical mark 5 is located inside the measuring unit 3, it is protected from external climatic influences and pollution. Pollution of the reflector lens 1 and the angular trihedral reflector 9 located at the end of the barrel has little effect on the quality (including shape) of the image of the optical mark 5, changing only its illumination, but not changing the distribution of illumination in the image. Therefore, the position of the image of the optical mark 5 in the plane of the photodetector 8 can be determined with an accuracy higher than the size of the image. The accuracy of measuring the bend of an artillery barrel in difficult operating conditions is increased.

A further increase in accuracy is achieved by the fact that the focal length of the lens of the reflector 1, mounted on the end of the barrel 2 in front of the corner triangular reflector 9, is equal to twice the distance from the optical mark 5 of the light shaper to this lens. In this case, after passing through the lens of the reflector 1, reflection from the angular trihedral reflector 9 and re-passing through the lens of the reflector 1 mounted on the end of the barrel 2, the light beam transfers the image of the optical mark 5 from the end of the barrel 2 to the measuring unit 3 in parallel beam paths. In such a scheme, all the energy of the light beam after reflection from the angular trihedral reflector 9 is sent without loss and vignetting to the measuring unit 3. In addition, in this scheme, the optical elements located at the end of the barrel are in the plane of the aperture diaphragm of the collimator formed by the emitter 4 with the optical grade 5 and the reflector lens 1 with an angular trihedral reflector 9. Therefore, the vignetting of the lens of such a collimator, caused by contamination of the reflector lens 1 in difficult operating conditions oviyah does not change the image quality of the optical mark 5 in the plane of the photodetector 8, does not change the nature of the illumination distribution at this image. The accuracy of determining the position of the image of the optical mark 5 in the plane of the photodetector 8 increases, the accuracy of measuring the bending of the barrel increases.

The accuracy of measuring the bending of the barrel in difficult operating conditions is also increased due to the fact that the optical beam imaging system 10 is included in the light shaper, and the focal length of the reflector lens 1 mounted in front of the corner triangular reflector 9 at the end of the barrel 2 is equal to twice the distance from image 11 of the optical mark to this lens (see FIG. 2).

The lens of the optical mark image forming system 10 transfers the optical mark image 5 outside the measuring unit 3 to position 11. The introduction of such an optical mark image forming system into the light beam former allows the optical mark image 11 to be removed from the protective window 12, which is usually always present in the measuring unit of any design. In this case, the effect of pollution of the protective window 12 of the measuring unit 3 on the measurement accuracy is reduced, since the protective window 12 can be installed in the plane of the aperture diaphragm of the optical marking system 10 in the light beam shaper and simultaneously in the plane of the aperture diaphragm of the receiving channel of the measuring unit 3.

The accuracy of measuring the bending of the barrel is also increased due to the fact that the reflector lens and the angular trihedral reflector mounted on the end of the barrel are made as a single monoblock part 13 of transparent material and are a triple prism with a spherical surface on its input face (see. figure 3). Such a combination of the lens and the angular trihedral reflector in a single part provides the ultimate stability of the relative positions of these optical elements of the device under any mechanical stress.

Information sources

1. Foreign military equipment. Surveys, a series of "Optics in weapons and military equipment", issue 20 (40), 1985, pp. 87-88.

2. Patent RU No. 2224980, IPC (7) G01B 11/00, publ. 02/27/2004, the prototype.

Claims (4)

1. A device for measuring the bend of an artillery barrel, comprising an optically conjugated angular trihedral reflector, an optical mark and a measuring unit, comprising a lens and a photodetector forming a receiving channel, an emitter and a beam splitter, characterized in that the optical mark is installed in the measuring block between the emitter and the beam splitter and forms a shaper of the light beam with the emitter, and a reflector lens is located in front of the corner trihedral reflector. 2. The device according to claim 1, characterized in that the focal length of the reflector lens is equal to twice the distance from the optical mark of the light beam former to this lens. 3. The device according to claim 1, characterized in that the measuring unit includes an optical brand image forming system that is optically coupled to the lens and the photodetector of the receiving channel, and the focal length of the reflector lens is twice the distance from the optical brand image to this lens. 4. The device according to any one of claims 1, 2 or 3, characterized in that the reflector lens and the angular trihedral reflector are made in the form of a single monoblock part made of transparent material, on the input face of which a spherical surface is made.

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