A method for finding the axis of a cylindrical object in practical engineering applications

Abstract

The present invention discloses a method for finding the axis of a cylindrical object in practical engineering applications. This method takes the axis finder as the original reference, and through the translation method, transfers its pointing accuracy to the laser indicator. When in use, again through the translation method, the spatial position where the axis of the measured cylindrical object is located is deduced. The laser indicator adopted by this method is composed of a bracket assembly, a yaw screw pair, a pitch screw pair, a spring, a laser and a fish-eye bearing. The laser is connected to the bracket assembly through the fish-eye bearing, so that the light beam of the laser always intersects with the central vertical plane of the laser indicator in space. Under the combined action of the yaw screw pair, the pitch screw pair and the spring, the laser adjusts the pitch angle and yaw angle of the laser beam respectively. The present invention provides an achievable way for measuring, calibrating and inspecting other equipment.

Description

Technical Field

[0001] The present invention belongs to the field of instruments and measurements, and particularly relates to a method for finding the axis of a cylindrical object in practical engineering applications. Background Art

[0002] Using this method, a laser indicator for calibrating a sight can be designed. A laser indicator is an instrument that makes a visible light beam highly parallel to the axis of a cylindrical or tubular object, and finds the intersection point of the axis of the cylindrical object and a far plane through the projection point of the visible light beam. There is a wide range of application requirements in the fields of instrument measurement, astronomical observation, military product inspection, etc.

[0003] For example, in the field of instrument measurement, to detect the perpendicularity between the cross-section and the axis of a cylindrical object, the laser indicator can be placed on the upper surface of the outer circumference of the cylinder, and then another laser beam is set below the projection point of the laser beam of the laser indicator on the far plane, making it parallel to the laser beam of the indicator and irradiating the cross-section of the cylinder. By measuring the distance between the projection point and the emission point of the reflected laser beam on the far plane, the perpendicularity between the cross-section and the axis of the cylindrical object can be calculated.

[0004] For example, in the field of astronomical observation, when an astronomical telescope observes a certain star, since the field of view of the astronomical telescope is very small, it is necessary to first point the telescope at this star to make it enter the field of view, and then make more detailed adjustments. By precisely fixing the laser indicator on the outer wall of the astronomical telescope barrel, the function of pointing at the star can be achieved.

[0005] For example, in the military field, for the inspection of the shooting accuracy of firearms, the barrel can be fixed parallel to the laser indicator. The translation of the projection point of the laser beam of the laser indicator by a certain distance is the ideal target point for firearm shooting. By comparing the distance between the actual target point and the ideal target point of the firearm, the circular error probability of the firearm shooting can be obtained. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for finding the axis of a cylindrical object in practical engineering applications, providing an achievable way for measuring, calibrating, and inspecting other devices.

[0007] The present invention is implemented by adopting the following technical solutions:

[0008] A method for finding the axis of a cylindrical object in engineering practical applications. This method takes the axis finder as the original reference, and through the translation method, transfers its pointing accuracy to the laser indicator. When in use, again through the translation method, the spatial position where the axis of the measured cylindrical object is located is deduced. The laser indicator used in this method consists of a bracket assembly, a yaw screw pair, a pitch screw pair, a spring, a laser and a fish-eye bearing. The laser is connected to the bracket assembly through the fish-eye bearing, so that the light beam of the laser always intersects with the mid-vertical plane of the laser indicator in space. Under the combined action of the yaw screw pair, the pitch screw pair and the spring, the laser adjusts the pitch angle and yaw angle of the laser beam respectively.

[0009] A further improvement of the present invention is that in practical applications, the laser indicator first obtains the accuracy and then is used.

[0010] A further improvement of the present invention is that the calibration process includes: fixing the calibrated axis finder on a plane; then horizontally placing the laser indicator on the upper surface of the outer circumference of the axis finder, and by adjusting the yaw screw pair and the pitch screw pair on the laser indicator, adjusting the yaw angle and pitch angle of the laser beam so that the distance between the projection point of the laser beam of the laser indicator at the far plane and the distance between the light source at the emission end of the laser beam are equal and in the longitudinal vertical plane, thus completing the acquisition of accuracy.

[0011] A further improvement of the present invention is that when in use, the laser indicator is horizontally placed on the upper surface of the outer circumference of the measured cylindrical object, and the laser indicator automatically aligns itself. There is a projection point of the laser beam of the laser indicator on the far plane. According to this projection point, mark a point downward at a distance L2 from the projection point, so as to find the projection point of the axis of the measured cylindrical object on the far plane.

[0012] A further improvement of the present invention is that the pointing accuracy of the laser indicator comes from the axis finder, and the positioning reference is realized through the outer circumferential surface of the measured cylindrical object.

[0013] A further improvement of the present invention is that the bracket assembly of the laser indicator adopts an inverted "V" shape design, realizing the function of automatically aligning the laser indicator on the outer circumferential surface of the cylindrical object.

[0014] A further improvement of the present invention is that the bracket assembly and the laser are connected through the fish-eye bearing, so that the light beam of the laser always intersects with the mid-vertical plane of the laser indicator in space, and the intersection point is the center of the ball of the fish-eye bearing.

[0015] A further improvement of the present invention is that under the combined constraints of the fish-eye bearing, the yaw screw pair, the pitch screw pair and the spring, the laser has only two degrees of freedom of pitch and yaw.

[0016] The present invention has at least the following beneficial technical effects:

[0017] Traditional methods use an indicator to find the axis. The indicator is a metal fixing block in an inverted "V" shape added to a dedicated firearm sight. The "V" is placed on a cylinder, and two people cooperate to find the aiming point of the sight in the distance, and then translate the aiming point by a certain distance to obtain the projection point of the cylinder axis in the distance. This indicator needs to be regularly sent to a professional optical calibration institution for calibration through a collimator to ensure the accuracy during the service life.

[0018] The main disadvantages of traditional indicators are as follows: (1) Large error. Due to manual operation by the human eye, the crosshair on the sight has a certain width, and the coincidence degree of the crosshairs at the front and rear ends of the sight during aiming will introduce errors due to the operator. When operating outdoors, sunlight will also interfere with the operator's vision, thereby affecting the accuracy; (2) Complex operation process. The point indicated by the indicator is invisible to the naked eye. When the cylinder needs to be moved or rotated, the process of finding the axis needs to be repeated, which is particularly time-consuming and laborious; (3) Require professional institution calibration. Generally, it needs to be sent to a professional optical calibration institution for calibration using a collimator, which brings time and financial expenses to users.

[0019] This method overcomes the disadvantages of the original aiming method. (1) The projection point of the laser beam is the projection point of the axis, eliminating the disadvantage of the manual aiming error being amplified by the straight-line distance; (2) The projection point of the laser is visible to the naked eye and does not require secondary translation, and the operation process is intuitive and simple; (3) This method can be completed anytime and anywhere, which is very convenient. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the structural composition of the laser indicator.

[0021] Figure 2 It is a schematic diagram of the laser indicator obtaining accuracy.

[0022] Figure 3 It is a schematic diagram of the laser indicator transmitting a parallel reference to obtain the intersection point of the axis of a cylindrical object and a far plane.

[0023] Figure 4 In (a) and (b), it is a schematic diagram of the laser indicator having different beam spacings for cylindrical objects with different diameters.

[0024] Description of the Reference Numerals:

[0025] 1 - Laser indicator, 2 - Bracket assembly, 3 - Yaw screw pair, 4 - Pitch screw pair, 5 - Spring, 6 - Laser, 7 - Fisheye bearing;

[0026] 8 - Far plane, 9 - Projection point of the laser indicator on the far plane when obtaining accuracy, 10 - Spacing between the projection points of two parallel laser beams on the far plane, 11 - Projection point of the laser beam of the axis finder on the far plane, 12 - Laser beam of the axis finder, 13 - Spacing between two parallel laser beams at the light source emission end when obtaining accuracy, 14 - Axis finder, 15 - Laser indicator, 16 - Laser beam of the laser indicator, 17 - Far plane, 18 - Projection point of the laser beam of the laser indicator on the far plane during use, 19 - Distance to be offset for positioning the intersection point of the axis of the cylindrical object and the far plane according to the laser indicator, 20 - Intersection point of the axis of the cylindrical object and the far plane, 21 - Axis of the cylindrical object, 22 - Spacing between the light source of the laser indicator and the center of the end face of the cylindrical object, 23 - Measured cylindrical object, 24 - Laser indicator, 25 - Laser beam of the laser indicator, 26 - Large cylindrical object, 27 - Radius R1 of the large cylindrical object, 28 - Maximum spacing H1 between the light source of the laser indicator and the end face circle of the large cylindrical object, 29 - Small cylindrical object, 30 - Radius R2 of the small cylindrical object, 31 - Maximum spacing H2 between the light source of the laser indicator and the end face circle of the small cylindrical object, 32 - Spacing L2 between the laser indicator and the center of the end face of the small cylindrical object, 33 - Spacing L1 between the laser indicator and the center of the end face of the large cylindrical object. Detailed implementation manners

[0027] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0028] A method for finding the axis of a cylindrical object in practical engineering applications, which is used to find the position of the intersection point 20 of the axis of the measured cylindrical object 23 and the ideal axis of the cylindrical object on the far plane 17. Its basic idea is precision transfer. First, through the parallel method, the direction of the laser beam 12 of the axis finder is transferred to the laser indicator 15, and then through the translation method, the intersection point 18 of the laser beam 25 of the laser indicator 24 on the far plane 17 is offset by a certain distance 19, and the intersection point 20 of the axis of the measured cylindrical object and the far plane is found. The specific approach is to first place the laser indicator on the upper circumferential surface of the axis finder 14, and adjust the angle of the laser beam 16 emitted by the laser indicator so that it is in a vertical plane and parallel to the laser beam 12 of the axis finder. Then, transfer the laser indicator 15 to the upper circumferential surface of the measured cylindrical object 23, and the projection point 18 of the laser beam of the laser indicator on the far plane. According to this projection point 18, mark a point 20 downward, with a length of 22 from the projection point 18, thus finding the projection point of the axis of the measured cylindrical object on the far plane.

[0029] The laser indicator 1 consists of parts such as a bracket assembly 2, a yaw screw pair 3, a pitch screw pair 4, a spring 5, a laser 6, and a fish-eye bearing 7. The bracket assembly 2 mainly has two functions: one is to fix all components, and the other is to make reliable contact with the measured cylindrical object through 4 legs. The yaw screw pair 3, pitch screw pair 4, spring 5, and fish-eye bearing 7 mainly play the role of finely adjusting the yaw angle and pitch angle of the laser, and in addition, the fish-eye bearing 7 ensures that the laser beam 16 of the laser indicator always intersects the mid-vertical plane of the laser indicator 15. The laser 6 mainly emits the laser beam 16 of the visible laser indicator, facilitating the positioning of the intersection points 9 of the laser with the far plane 8 and the far plane 17 and the projection point 18 of the laser beam of the laser indicator on the far plane.

[0030] The working principle of the laser indicator is as follows: The axis finder can output a laser ray that is highly coaxial with its outer cylindrical surface. When the laser indicator is placed on the upper circumferential surface of the axis finder, the bracket has a reference zero position for direction. Adjust the direction of the laser beam of the laser indicator so that it is in the vertical plane where the laser beam of the axis finder is located, and the distance between the projection ends of the two laser beams is equal to the distance between the emission ends. Then these two laser beams are parallel in space, and the laser indicator completes the process of obtaining precision from the axis finder. After obtaining the precision, when the laser indicator is placed on the circumferential surface of any cylindrical object, the laser emitted by it is parallel to the axis of this cylindrical object.

[0031] The usage method of the laser indicator mainly consists of three steps: obtaining parallel accuracy, transmitting the reference, and finding the intersection point. The specific method for obtaining accuracy in the first step is as follows: Fix the calibrated axis finder on a plane, such as an optical bench. Then place the laser indicator 15 on the upper surface of the outer circumference of the axis finder 14, and adjust the yaw angle and pitch angle of the laser beam to make it parallel to the laser beam of the axis finder 14, thus obtaining the parallel accuracy. The specific method for transmitting the parallel reference in the second step is as follows: Horizontally place the laser indicator 24 on the upper surface of the outer circumference of the cylindrical object 23 to be measured. The inverted "V" shape of the laser indicator assembly enables automatic alignment. At this time, the laser beam 25 of the laser indicator 24 is parallel to the axis of the invisible cylindrical object to be measured. The specific method for finding the intersection point in the third step is as follows: On the far plane 17, mark a distance 19 downward according to the projection point 18 of the laser beam of the laser indicator, and then the projection point of the axis 21 of the cylindrical object on the far plane 17 is found. This distance 19 is equal to the distance 22 at the light source.

[0032] In theory, by infinitely increasing the distance between the laser indicator and the far plane, the parallel accuracy of the operation process can be infinitely improved. However, this cannot be achieved in engineering because it is restricted by engineering realities, such as the roundness of the mechanical processing of the axis finder and the cylindrical object to be measured, surface roughness, hardness of the material itself, divergence angle of the laser light source beam, attenuation of the laser beam by the atmosphere, fineness of the fine adjustment of the screw pair, stability of the placement of the V-shaped iron, and other engineering factors and natural environmental factors. At the same time, the laser indicator is also restricted by engineering factors and natural environmental factors such as the flatness, roughness, and hardness of the contact surface between the support assembly and the axis finder, divergence angle of the laser light source beam, attenuation of the laser beam by the atmosphere, and fineness of the fine adjustment of the screw pair. In addition, the outer circumferential surface of the cylindrical object to be calibrated should also have good roundness and surface roughness in order to cooperate stably with the laser indicator and achieve the purpose of accurate laser beam indication.

[0033] Although the present invention has been described in detail with general descriptions and specific implementation examples above, based on the present invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A method for finding the axis of a cylindrical object in practical engineering applications, characterized in that, This method uses the laser beam of the axis finder as the original reference. Through the translation method, its pointing accuracy is transmitted to the laser indicator. When in use, again through the translation method, the spatial position where the axis of the measured cylindrical object is located is deduced. The laser indicator (1) used in this method consists of a bracket assembly (2), a yaw screw pair (3), a pitch screw pair (4), a spring (5), a laser (6) and a fish-eye bearing (7). The laser (6) is connected to the bracket assembly (2) through the fish-eye bearing (7). The beam of the laser (6) always intersects the central vertical plane of the laser indicator (1) in space. Under the combined action of the yaw screw pair (3), the pitch screw pair (4) and the spring (5), the laser (6) adjusts the pitch angle and yaw angle of the laser beam respectively. In practical applications, the laser indicator (1) first obtains the accuracy and then is used. The calibration process is to fix the calibrated axis finder (14) on a plane. Then, the laser indicator (15) is horizontally placed on the upper surface of the outer circumference of the axis finder (14). By adjusting the yaw screw pair (3) and the pitch screw pair (4) on the laser indicator (15), the yaw angle and pitch angle of the laser beam are adjusted so that the distance (10) between the projection points of the laser beams of the axis finder (14) and the laser indicator (15) at the far plane (8) is equal to the distance (L1) from the light source at the emitting end of the laser beam, and in the longitudinal vertical plane, thus completing the acquisition of accuracy. When in use, the laser indicator (24) is horizontally placed on the upper surface of the outer circumference of the measured cylindrical object (23). The laser indicator (24) automatically aligns itself. There is a projection point (18) of the laser beam of the laser indicator (24) on the far plane (17). According to this projection point, a point (20) is marked downward at a certain distance (22) from the projection point (18), thus finding the projection point of the axis (21) of the measured cylindrical object (23) on the far plane (17).

2. A method for finding the axis of a cylindrical object in practical engineering applications according to claim 1, characterized in that The pointing accuracy of the laser indicator (1) comes from the axis finder and realizes the positioning reference through the outer circumferential surface of the measured cylindrical object.

3. A method for finding the axis of a cylindrical object in practical engineering applications according to claim 1, characterized in that, The bracket assembly (2) of the laser indicator (1) adopts an inverted "V" shape design, realizing the function of automatically aligning the laser indicator (1) on the outer circumferential surface of the cylindrical object.

4. A method for finding the axis of a cylindrical object in practical engineering applications according to claim 1, characterized in that, The bracket assembly (2) and the laser (6) realize that the beam of the laser always intersects the central vertical plane of the laser indicator in space through the fish-eye bearing (7), and the intersection point is the center of the ball of the fish-eye bearing.

5. A method for finding the axis of a cylindrical object in practical engineering applications according to claim 4, characterized in that, Under the combined constraints of the fish-eye bearing (7), the yaw screw pair (3), the pitch screw pair (4) and the spring (5), the laser (6) has only two degrees of freedom: pitch and yaw.

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