Abbe error measuring device of leveling staff

Abstract

The utility model relates to the field of measurement, in particular to an Abbe error measuring device of a leveling staff, which comprises a guide rail parallel to the leveling staff to be measured, a working table is in sliding fit with the guide rail, and a lens for monitoring graduation scales of the leveling staff is mounted on the working table; the measuring device further comprises a laser interferometer installed on the light source table and a light splitting assembly used for dispersing emitted light of the laser interferometer, and the light splitting assembly disperses the emitted light of the laser interferometer into a first light path and a second light path which are parallel to each other. A reflecting assembly used for reflecting a first light path and a second light path in the same way is arranged on the workbench, the first light path is reflected back into the laser interferometer after being reflected, and the second light path enters the four-quadrant detector after being reflected. According to the utility model, the abbe error of the leveling staff can be accurately measured.

Description

Technical Field

[0001] The utility model relates to the field of measurement, in particular to an Abbe error measuring device for a leveling rod. Background Art

[0002] The leveling rod is a rod used for leveling measurement. Its structure is as described in the patent number "CN220583390U". It is made of high-quality wood or fiberglass, aluminum alloy and other materials. The average value of the interval length of the high-grade leveling rod and the error of each decimeter division have the following requirements: the difference between the average value of the meter interval length and the nominal value shall not exceed 0.1mm for one rod and 0.05mm for a pair of rods; the standard deviation of the scale of a row of divisions shall not exceed 13μm.

[0003] When using a level rod for daily measurement, there is often an Abbe error. The Abbe error refers to the error caused when the measuring axis of the measuring instrument is not in the same straight line as the axis of the sample to be measured. This error is caused by the limitations of the structure, manufacturing and use of the measuring instrument, which makes the measuring axis not coincide with the reference axis or not on its extension line, thus violating the Abbe principle (that is, "accurate measurement results can only be obtained if the measuring axis is on the extension line of the reference axis"). The Abbe error can be divided into static Abbe error and dynamic Abbe error. The static Abbe error is the error when the workbench stops moving, while the dynamic Abbe error is the error caused by the deformation of the transmission mechanism thrust during the movement. The Abbe error has an important influence on the measurement accuracy, especially in high-precision measurement. Therefore, how to eliminate the Abbe error has always been a problem to be solved in the field of measurement. Utility Model Content

[0004] In order to avoid and overcome the technical problems existing in the prior art, the utility model provides an Abbe error measuring device for a leveling rod. The utility model can realize accurate measurement of the Abbe error of the leveling rod.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A device for measuring the Abbe error of a leveling rod comprises a guide rail arranged in parallel with the leveling rod to be measured, a workbench slidably cooperates with the guide rail, and a lens for monitoring the graduation scale of the leveling rod is installed on the workbench; the measuring device also comprises a laser interferometer installed on a light source table and a spectroscopic component for dispersing the emitted light of the laser interferometer, the spectroscopic component disperses the emitted light of the laser interferometer into two groups of parallel first light paths and second light paths, a reflection component for reflecting the first light path and the second light path in the original path is arranged on the workbench, the first light path is reflected back into the laser interferometer after reflection, and the second light path enters a four-quadrant detector after reflection.

[0007] As a further solution of the utility model: the splitter assembly includes a first cubic beam splitter and a second cubic beam splitter arranged side by side, a quarter wave plate is fixed at the transmitted light outlet of the first cubic beam splitter, and the transmitted light of the first cubic beam splitter forms a first optical path after passing through the quarter wave plate; a first corner prism lens is fixed at the reflected light outlet of the first cubic beam splitter, and the reflected light of the first cubic beam splitter is reflected by the first corner prism lens and returns to the first cubic beam splitter, and a part of it is transmitted to the second cubic beam splitter, and is reflected by the second cubic beam splitter to form a second optical path, and the other part is reflected back to the laser interferometer.

[0008] As a further solution of the utility model: the reflection component on the workbench includes a second corner prism lens and a reflector. The light of the first optical path is reflected by the second corner prism lens and then reflected back into the laser interferometer through the first cubic beam splitter; the light of the second optical path is reflected by the reflector and then emitted into the four-quadrant detector through the second cubic beam splitter.

[0009] As a further solution of the utility model: a grating ruler is arranged on the guide rail along the length direction.

[0010] As a further solution of the utility model: the lens includes an optical microscope lens and a camera which are closely attached to the graduation scale of the leveling ruler.

[0011] As a further solution of the utility model: the laser interferometer, the four-quadrant detector and the lens are all connected to the data processing module to perform data conversion.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] 1. The laser interferometer of the utility model is combined with a four-quadrant detector to obtain the angle between the measuring axis and the reference axis in the Y-axis and Z-axis space generated by the movement of the slide rail position in real time through the comparison of two groups of optical paths; since the lens is fixed on the workbench, its relative position with the movable workbench will not change, so when the X-axis deviation distance of the workbench is known, through image recognition and processing, the line width and position of the initial zero position mark of the leveling scale are used as reference values, and the Abbe error of the measured value of each measuring point of the measured leveling scale can be corrected. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] In the figure:

[0016] 1. Light source table; 11. Laser interferometer; 12. First cubic beam splitter; 13. First corner prism lens;

[0017] 14. Quarter wave plate; 15. Second cubic beam splitter; 16. Four-quadrant detector;

[0018] 2. Leveling scale; 3. Guide rail; 31. Grating ruler;

[0019] 4. Workbench; 41. Lens; 42. Second angle prism lens; 43. Reflector;

[0020] 5. Data processing module; 6. First optical path; 7. Second optical path. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] See also Figure 1 In the embodiment of the utility model, an Abbe error measuring device for a leveling rod is provided, and the error measuring device comprises a guide rail 3 and a leveling rod 2 which are simultaneously mounted on a fixed platform, and the leveling rod 2 is arranged in parallel with the guide rail 3. A grating ruler 31 is arranged on the guide rail 3 along the length direction of the guide rail, and a workbench 4 is mounted on the guide rail 3 and slidably cooperates with the guide rail 3. By sliding the workbench 4 along the length direction of the guide rail 3, the measurement of different measuring points of the leveling rod 2 can be realized.

[0023] A lens 41 is installed on the workbench 4. The lens 41 is composed of an optical microscope lens and a camera, and is used to magnify and observe and record the scale marks at different measuring points of the leveling staff 2.

[0024] A light source platform 1 is installed on the side of the fixed platform, and a laser interferometer 11 is installed on the light source platform 1 to emit light in a direction parallel to the leveling scale 2. The laser interferometer 11 has a temperature, humidity and atmospheric pressure compensation system.

[0025] A first cubic beam splitter 12 is installed at the downstream end of the light source outlet of the laser interferometer 11 , and a second angular prism lens 42 located on the same straight line as the laser interferometer 11 and the first cubic beam splitter 12 is installed on the workbench 4 .

[0026] A second cubic beam splitter 15 arranged in parallel with the first cubic beam splitter 12 is also installed on the light source table 1, and a reflector 43 corresponding to the position of the second cubic beam splitter 15 is installed on the workbench 4. A four-quadrant detector 16 is installed on the side of the second cubic beam splitter 15 away from the reflector 43, and the four-quadrant detector 16, the second cubic beam splitter 15 and the reflector 43 are located on the same straight line.

[0027] One end of the first cubic beam splitter 12 away from the second cubic beam splitter 15 is a reflection surface outlet, and a first corner prism lens 13 is installed at the reflection surface outlet of the first cubic beam splitter 12 .

[0028] The end of the first cubic beam splitter 12 away from the laser interferometer 11 is a transmission surface outlet, and a quarter wave plate 14 is installed at the transmission surface outlet. Along the laser emission direction, the reflector 43 and the second corner prism lens 42 are arranged in parallel.

[0029] After the laser interferometer 11 emits the laser, when the laser passes through the first cubic beam splitter 12, a portion of the laser is transmitted through the first cubic beam splitter 12 and passes through the quarter-wave plate 14 to form a first optical path 6. The first optical path 6 is reflected by the second corner prism lens 32 and then reflected back to the laser interferometer 11.

[0030] After being reflected by the first cubic beam splitter 12 and changing the direction of the laser through the first prism lens 13, the laser leaves the first cubic beam splitter 12 and is reflected by the second cubic beam splitter 15 to form a second optical path 7 approximately parallel to the first optical path 6. The second optical path 7 is used to detect the deviation angle from the measuring axis of the leveling scale 2 caused by the movement of the workbench. After being reflected by the reflector 43, the laser of the second optical path 7 passes through the second cubic beam splitter 15 and is incident on the four-quadrant detector 16.

[0031] The measurement steps are as follows:

[0032] S1. Install the Abbe error measuring device, fix the leveling rod 2 to be measured, and turn on the light source table 1;

[0033] S2, debug the optical path so that the outgoing light of the second cubic beam splitter 15 stays at the center point of the four-quadrant detector 16, so that the laser interferometer 11 is in a zero position waiting for measurement;

[0034] S3, move the workbench 4 along the guide rail 3, locate the scale divisions of different measuring points of the leveling ruler 2 through the lens 41, synchronously read the position of the light spot in the four-quadrant detector 16, and calculate the offset angle θ between the measuring axis of the current measuring point and the reference axis.

[0035] The laser interferometer 11, the four-quadrant detector 16 and the lens 42 are all connected to the data processing module 5. The position of the workbench 4 is moved by the control software to measure different positions of the leveling rod 2. The position of the light spot in the four-quadrant detector 16 is read by the data processing module 5. The actual distance is obtained by converting the four-quadrant detector 16 according to its radius and pixel coordinates. By measuring the distance with the laser interferometer 11 and calculating according to the trigonometric function, the offset angle between the measurement axis of the current measurement position and the reference axis can be obtained.

[0036] S4, calculating the indication error Δl of the leveling rod 2 according to the offset angle θ of different measuring points;

[0037] The indication error Δl is:

[0038] Δl=l t / (1+cΔt)-l s

[0039] Among them, l t Indicates the actual measurement value of the current measuring point of the leveling staff;

[0040] c represents the linear expansion coefficient of the leveling rod 2;

[0041] Δt represents the deviation of the actual temperature from the standard temperature during measurement;

[0042] l s Indicates the actual distance of the current measuring point.

[0043]

[0044] Among them, l 标 Indicates the nominal value of the current measuring point of leveling rod 2;

[0045] α represents the offset angle between the measuring axis of the current measuring point and the ideal axis;

[0046] a represents the horizontal displacement between the measuring axis and the ideal axis;

[0047] b represents the vertical displacement between the measuring axis and the ideal axis.

[0048] a=kΔY-x;

[0049] b=(Z i -Z0)×h;

[0050] Wherein, k represents the actual distance corresponding to each pixel at the current magnification of the lens 41;

[0051] ΔY represents the pixel distance difference between the current measurement point and the initial position due to the position difference in the horizontal direction; x represents the x-axis coordinate value of the light spot identified by the four-quadrant detector 16;

[0052] Z i Indicates the pixel width of the scale line at the current measurement point;

[0053] Z0 represents the pixel width of the initial position line of leveling rod 2;

[0054] h represents the actual distance value corresponding to each pixel in the vertical direction of the lens 41.

[0055]

[0056] Wherein, l represents the measurement distance of the laser interferometer 11;

[0057] θ represents the offset angle between the measuring axis of the current measuring point and the reference axis;

[0058]

[0059] x represents the x-axis coordinate value of the light spot identified by the four-quadrant detector 16;

[0060] y represents the y-axis coordinate value of the light spot identified by the four-quadrant detector 16 .

[0061]

[0062] Among them, d x It represents the offset of the light spot of the four-quadrant detector 16 relative to the center origin in the x-axis coordinate; d y Indicates the offset of the light spot of the four-quadrant detector 16 relative to the center origin in the y-axis coordinate;

[0063] I A represents the output current of the first quadrant of the four-quadrant detector 16;

[0064] I B represents the output current of the second quadrant of the four-quadrant detector 16;

[0065] I C represents the output current of the third quadrant of the four-quadrant detector 16;

[0066] I D represents the output current of the fourth quadrant of the four-quadrant detector 16;

[0067] r represents the actual radius value of the four-quadrant detector 16

[0068] S5. Correct the leveling rod 2 according to the indication error Δl of different measuring points to eliminate the Abbe error.

[0069] The measurement results are outputted by the measurement software of the measurement data processing module and the original records are generated. By comparing with the display value of the grating ruler 31, the Abbe error of the measurement result of the measured leveling ruler 2 can be reduced by about 70%-85%, which significantly improves the accuracy of the entire measurement system.

[0070] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0071] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

Claims

1. An Abbe error measuring device for a leveling rod, characterized in that: The measuring device comprises a guide rail (3) arranged in parallel with a leveling rod (2) to be measured, a workbench (4) slidably matched with the guide rail (3), and a lens (41) for monitoring the graduations of the leveling rod (2) is mounted on the workbench (4); the measuring device also comprises a laser interferometer (11) mounted on the light source table (1) and a light splitting component for dispersing the emitted light of the laser interferometer (11), the light splitting component disperses the emitted light of the laser interferometer (11) into two groups of parallel first light paths (6) and second light paths (7), and a reflection component for reflecting the first light path (6) and the second light path (7) in the original path is arranged on the workbench (4), the first light path (6) is reflected back into the laser interferometer (11) after reflection, and the second light path (7) enters a four-quadrant detector (16) after reflection.

2. The Abbe error measuring device for a leveling rod according to claim 1, characterized in that: The light splitting component comprises a first cubic beam splitter (12) and a second cubic beam splitter (15) arranged side by side; a quarter wave plate (14) is fixed at the transmission light outlet of the first cubic beam splitter (12); the transmitted light of the first cubic beam splitter (12) forms a first light path (6) after passing through the quarter wave plate (14); a first angular prism lens (13) is fixed at the reflection light outlet of the first cubic beam splitter (12); the reflected light of the first cubic beam splitter (12) is reflected by the first angular prism lens (13) and then returns to the first cubic beam splitter (12); a part of the reflected light is transmitted into the second cubic beam splitter (15), and a second light path (7) is formed after being reflected by the second cubic beam splitter (15); the other part of the reflected light is reflected back to the laser interferometer (11).

3. The Abbe error measuring device for a leveling rod according to claim 2, characterized in that: The reflection component on the workbench (4) comprises a second prism lens (42) and a reflector (43); the light of the first optical path (6) is reflected by the second prism lens (42) and then reflected back into the laser interferometer (11) through the first cubic beam splitter (12); the light of the second optical path (7) is reflected by the reflector (43) and then reflected into the four-quadrant detector (16) through the second cubic beam splitter (15).

4. The Abbe error measuring device for a leveling staff according to any one of claims 1 to 3, characterized in that: A grating ruler (31) is arranged on the guide rail (3) along the length direction.

5. The Abbe error measuring device for a leveling staff according to any one of claims 1 to 3, characterized in that: The lens (41) comprises an optical microscope lens and a camera which are closely attached to the graduation scale of the leveling ruler (2).

6. The Abbe error measuring device for a leveling staff according to any one of claims 1 to 3, characterized in that: The laser interferometer (11), the four-quadrant detector (16) and the lens (41) are all connected to the data processing module (5) to perform data conversion.

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