Optical axis measuring machine

Abstract

The utility model discloses optical axle type measuring machine, including mounting bracket and rotary platform, be rotated and be connected with lower centre in the rotary platform, the top of mounting bracket is provided with two servo motors, and the output of every servo motor all is connected with ball screw through shaft coupling, is installed with mounting seat through ball nut on the ball screw of mounting bracket front, and rotatingly connected with upper centre on the mounting seat, the utility model adopts visual system and parallel light source cooperation's non -contact measurement, avoids the workpiece scratch caused by traditional contact type tool, solves the slender axle measurement deformation problem, guarantees workpiece form and measurement accuracy, when roundness measurement, by DD motor drive part uniform speed rotation, visual system fixed point high -efficient capture circumferential profile data, need not complex manual operation, shortens single piece measurement time, can adapt to production field fast sampling inspection and batch detection, solves traditional contact type tool low -efficiency problem.

Description

Technical Field

[0001] This utility model mainly relates to the field of optical measurement and mechanical manufacturing testing technology, specifically to optical shaft measuring machines. Background Technology

[0002] In the field of mechanical manufacturing, the dimensional accuracy (such as diameter and roundness) and geometric tolerance (such as straightness) of shaft parts are key indicators affecting product performance, and their measurement accuracy and efficiency are directly related to production quality and capacity.

[0003] Traditional contact measuring tools (such as calipers, micrometers, and ring gauges) require direct contact with the workpiece surface, resulting in low measurement efficiency, difficulty in meeting batch inspection needs, and easy scratching of the workpiece surface. Especially when measuring slender shafts, the contact force can easily cause workpiece deformation, directly affecting measurement accuracy. While coordinate measuring machines (CMMs) can achieve high-precision measurement, they suffer from high cost, complex operation procedures, and stringent environmental requirements (such as temperature, humidity, and vibration). Furthermore, their measurement speed is relatively slow, making them suitable only for precision laboratory testing and unsuitable for rapid sampling or batch inspection scenarios in production environments. Some existing optical measuring devices (such as projectors and imagers) employ non-contact measurement principles, avoiding the drawbacks of contact measurement. However, they still have shortcomings in shaft part inspection: they typically require complex clamping procedures, repeated focusing operations, and cumbersome image processing, leading to low measurement efficiency. Especially for long shaft parts or scenarios requiring multi-section measurement, the increased operational complexity makes it difficult to meet the demand for efficient inspection. Therefore, an optical shaft measuring machine is needed. Utility Model Content

[0004] This utility model provides a significantly different solution to the problem of overly simplistic existing technical solutions. It primarily offers an optical shaft measuring machine to address the issues raised in the background section regarding traditional contact measuring tools (such as calipers and micrometers), which suffer from low efficiency, easy scratching of the workpiece, and deformation affecting accuracy when measuring slender shafts. While coordinate measuring machines offer high accuracy, they are expensive, complex to operate, have stringent environmental requirements, and are slow, making them unsuitable for rapid or batch testing in production environments. Furthermore, some existing optical measuring devices (such as projectors and imagers), although non-contact, suffer from complex clamping, focusing, and image processing, resulting in low measurement efficiency, especially for measuring long shafts or multi-section sections, where operation is cumbersome.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: An optical axis measuring machine includes a mounting frame and a rotary platform, with a lower center rotatably connected to the rotary platform. Two servo motors are mounted on the top of the mounting frame, each servo motor's output end connected to a ball screw via a coupling. A mounting seat is mounted on the ball screw located in front of the mounting frame via a ball nut, and an upper center is rotatably connected to the mounting seat. A mounting platform is mounted on the ball screw located behind the mounting frame via a ball nut, and a vision system is mounted on the mounting platform.

[0006] More preferably, the bottom of the mounting frame is provided with a base plate, a rotating platform is mounted on the base plate, and multiple equally spaced screw holes are provided on the base plate.

[0007] More preferably, the rotary platform is equipped with a DD motor, the output end of which is connected to the lower center via a coupling, for driving the lower center to rotate, thereby driving shaft parts to rotate.

[0008] More preferably, both ends of the mounting bracket are provided with vertically symmetrically distributed linear guide rails, and the mounting base and the mounting platform are slidably engaged with the corresponding linear guide rails through symmetrically distributed sliders.

[0009] More preferably, the vision system consists of a line scan camera, a telecentric lens, and a parallel light source, used to realize 2D image acquisition and 3D contour acquisition of shaft-type parts.

[0010] More preferably, both sides of the mounting bracket are vertically parallel linear grating rulers for triggering the linear scan camera to acquire images.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: This shaft measuring machine employs a measurement method that combines a vision system with a parallel light source, ensuring no direct contact with the workpiece surface throughout the entire process. This fundamentally avoids the surface scratches caused by contact forces in traditional contact measuring tools (such as calipers and micrometers), making it particularly suitable for shaft parts with high surface precision requirements. Simultaneously, it effectively solves the problem of deformation easily occurring in slender shafts during contact measurement, ensuring the original shape of the workpiece and measurement accuracy. Furthermore, a servo motor drives a ball screw and linear guide rail to achieve uniform-speed automatic scanning along the axial direction. Combined with real-time triggering by a linear grating ruler, it can quickly complete the acquisition of two-dimensional parameters for the entire length of the part. During roundness measurement, a DD motor drives the part to rotate at a uniform speed, and the vision system efficiently captures the circumferential contour data at a fixed point, eliminating the need for complex manual clamping, repeated focusing, and tedious manual operations. This shortens the measurement time for a single piece and adapts to rapid sampling and batch inspection scenarios in production environments, solving the problems of low efficiency in traditional contact tools and slow speed of coordinate measuring machines.

[0012] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional structural diagram of the present invention.

[0014] Numbering on the map: 1. Mounting bracket; 2. Base plate; 3. Rotary platform; 4. Lower center; 5. DD motor; 6. Servo motor; 7. Ball screw; 8. Mounting base; 9. Upper center; 10. Linear guide rail; 11. Mounting platform; 12. Vision system. Detailed Implementation

[0015] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the disclosure of the utility model more thorough and comprehensive.

[0016] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0017] Please refer to the appendix carefully. Figure 1-2 An optical shaft measuring machine includes a mounting frame 1 and a rotary platform 3. A lower center 4 is rotatably connected to the rotary platform 3. Two servo motors 6 are installed on the top of the mounting frame 1. The output end of each servo motor 6 is connected to a ball screw 7 via a coupling. Mounting blocks are symmetrically distributed about the horizontal center line of the ball screw 7 at both ends of the mounting frame 1, and the ball screw 7 is rotatably connected to the corresponding mounting block. A mounting seat 8 is installed on the ball screw 7 located in front of the mounting frame 1 via a ball nut, and an upper center 9 is rotatably connected to the mounting seat 8. A pressure sensing module is provided between the mounting seat 8 and the upper center 9. A mounting platform 11 is installed on the ball screw 7 located behind the mounting frame 1 via a ball nut, and a vision system 12 is mounted on the mounting platform 11.

[0018] In this embodiment, as Figure 1 and Figure 2As shown, the bottom of the mounting frame 1 is provided with a base plate 2, on which a rotating platform 3 is mounted, and multiple equally spaced screw holes are provided on the base plate 2; the base plate 2 provides support for the equipment, and the multiple equally spaced screw holes on the base plate 2 provide flexible and diverse options for the installation and fixing of the equipment, and the appropriate screw hole position can be selected for fixing according to the actual installation requirements, adapting to different installation scenarios and connection requirements.

[0019] In this embodiment, as Figure 1 and Figure 2 As shown, a DD motor 5 is installed on the rotary platform 3. The output end of the DD motor 5 is connected to the lower center 4 via a coupling, which is used to drive the lower center 4 to rotate. The output end of the DD motor 5 is coaxially connected to a rotary encoder for real-time feedback of the rotation angle of the part. The linear array camera of the vision system 12 triggers the acquisition and synchronizes with the angle signal to realize the circumferential contour data to be aligned and stitched according to the angle. When the linear module composed of linear guide rail 10, ball screw 7 and servo motor 6 operates, it will drive the mounting base 8 and the upper center 9 to move down synchronously. During this process, the center hole on the lower end face of the shaft part first makes precise contact with the lower center 4. Then the upper center 9 continues to descend and abuts against the center hole on the upper end face of the part, thereby completing the stable clamping of the shaft part. At this time, the DD motor 5 drives the lower center 4 to rotate, which can synchronously drive the clamped shaft part to rotate, providing convenient conditions for the vision system 12 to measure the part in all directions.

[0020] In this embodiment, as Figure 1 and Figure 2 As shown, vertically symmetrical linear guide rails 10 are provided at both the front and rear ends of the mounting bracket 1. The mounting base 8 and the mounting platform 11 are slidably engaged with the corresponding linear guide rails 10 through symmetrically distributed sliders. When the linear module composed of the linear guide rails 10, ball screws 7 and servo motors 6 drives the mounting base 8 or mounting platform 11 to move up or down, the sliders on the mounting base 8 or mounting platform 11 will slide smoothly along the corresponding linear guide rails 10. This structural design can improve the stability of the mounting base 8 or mounting platform 11 during the up and down movement.

[0021] In this embodiment, as Figure 1 and Figure 2 As shown, the vision system 12 is composed of a line scan camera, a telecentric lens, and a parallel light source. When working, the vision system 12 projects a parallel light source from one side. When the parallel light source illuminates the shaft-like parts, the parts will block the light, while the unblocked light on both sides will enter the telecentric lens on the other side of the vision system 12 and be received by the line scan camera. At this time, a pixel image (i.e., a one-dimensional image) with white on both sides and black in the middle can be displayed on the software interface.

[0022] When the vision system 12 moves up and down under the drive of the linear module, it will trigger a signal through the linear grating ruler to acquire multiple one-dimensional pixel images. After these one-dimensional pixel images are stitched together, they can form a complete two-dimensional image. Finally, by using SIEGVM measurement software to analyze and calculate the two-dimensional image, the various dimensional parameters of the shaft parts, including length, diameter, chamfer, etc., can be accurately obtained.

[0023] In this embodiment, as Figure 1 and Figure 2 As shown, both sides of the mounting bracket 1 are vertically parallel to each other with linear grating rulers, which are used to trigger the line scan camera to acquire images. The linear grating rulers can provide high-precision position feedback. The parallel arrangement on both sides can form a two-way position reference, ensuring that the line scan camera can accurately correspond to the specific height position of the target object when triggering acquisition. This avoids image acquisition position offset caused by unilateral positioning error, and ensures that image data at different times and positions maintain strict consistency in the spatial dimension, providing a reliable position benchmark for subsequent image stitching, size measurement and other processing.

[0024] The specific operating procedure of this utility is as follows: During operation, the shaft part to be tested is first placed on the lower center 4 of the rotary platform 3 (before the upper center 9 descends, the servo motor 6 of the drive mounting platform 11 moves the vision system 12 to the safe area above the base plate 2; after clamping, scanning is started). The servo motor 6 in front of the mounting frame 1 is started to drive the ball screw 7 to rotate, which drives the mounting seat 8 to move down along the linear guide rail 10, so that the upper center 9 on the mounting seat 8 is pressed into the center hole at the top of the part to complete the clamping (at this time, the lower center 4 and the upper center 9 are coaxially positioned, the pressure sensing module senses the pressure, and the set threshold pressure automatically stops the downward movement).

[0025] Then, the servo motor 6 at the rear is activated to drive the corresponding ball screw 7, which in turn drives the vision system 12 on the mounting platform 11 to move at a constant speed from the initial position on the base plate 2. During the movement, the linear grating rulers on both sides of the mounting frame 1 (providing bidirectional position references) trigger the line scan camera of the vision system 12 in real time. After the beam of the parallel light source is blocked by the part, the line scan camera acquires a one-dimensional pixel image of the light and dark boundary (a line with white on both sides and black in the middle) frame by frame.

[0026] Once the vision system 12 has traveled a distance covering the entire length of the part, the measurement software stitches together thousands of one-dimensional images into a two-dimensional image based on the position data of the grating ruler, and accurately analyzes parameters such as the length, diameter, and chamfer of the part.

[0027] After completing the two-dimensional measurement, the vision system 12 returns to the bottom. If roundness measurement is required, the servo motor 6 is driven to precisely position the vision system 12 at the target height, and the DD motor 5 is started to drive the lower tip 4 and the part to rotate at a constant speed through the rotary platform 3. At this time, the vision system 12 captures the circumferential contour data at a fixed position, and the measurement software generates a roundness diagram through 360° contour points and calculates three-dimensional parameters such as the cross-sectional roundness error.

[0028] After measurement, the upper center 9 rises and resets to remove the part. The entire process ensures movement accuracy through the ball screw 7 and linear guide rail 10, micron-level triggering through the linear grating ruler, and backlash-free rotation through the DD motor 5, forming a complete measurement flow of lower center 4 / upper center 9 clamping - vision system 12 axial scanning (two-dimensional dimension) - part rotation and fixed-point acquisition (three-dimensional contour).

[0029] The present invention has been described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. An optical shaft measuring machine, comprising a mounting frame (1) and a rotary platform (3), characterized in that: The rotary platform (3) is rotatably connected to a lower center (4); the top of the mounting frame (1) is provided with two servo motors (6), and the output end of each servo motor (6) is connected to a ball screw (7) through a coupling; a mounting seat (8) is installed on the ball screw (7) located in front of the mounting frame (1) through a ball nut, and an upper center (9) is rotatably connected on the mounting seat (8); a mounting platform (11) is installed on the ball screw (7) located behind the mounting frame (1) through a ball nut, and a vision system (12) is mounted on the mounting platform (11).

2. The optical shaft measuring machine according to claim 1, characterized in that: The mounting bracket (1) has a base plate (2) at its bottom, a rotating platform (3) is mounted on the base plate (2), and multiple equally spaced screw holes are provided on the base plate (2).

3. The optical shaft measuring machine according to claim 1, characterized in that: The rotary platform (3) is equipped with a DD motor (5). The output end of the DD motor (5) is connected to the lower center (4) through a coupling. It is used to drive the lower center (4) to rotate, thereby driving the shaft parts to rotate.

4. The optical shaft measuring machine according to claim 1, characterized in that: The mounting bracket (1) is provided with vertically symmetrically distributed linear guide rails (10) at both the front and rear ends. The mounting base (8) and the mounting platform (11) are both connected to the corresponding linear guide rails (10) through symmetrically distributed sliders.

5. The optical shaft measuring machine according to claim 4, characterized in that: The vision system (12) consists of a line array camera, a telecentric lens and a parallel light source, and is used to realize 2D image acquisition and 3D contour acquisition of shaft parts.

6. The optical shaft measuring machine according to claim 1, characterized in that: The mounting bracket (1) has vertically parallel linear grating rulers on both sides for triggering the linear array camera to acquire images.

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