A multi-read head circular grating sensor assembling device and assembling method

Abstract

This invention discloses an assembly and adjustment device and method for a multi-readhead circular grating sensor, belonging to the field of precision angle measurement technology. It solves the problems of complex operation and difficulty in guaranteeing high-precision angle measurement requirements in existing installation and adjustment processes. The device includes: a mounting hub; a circular grating code disk with an annular grating code pattern coaxially arranged on its upper surface; a transparent mounting pad with an annular first graphic area, multiple second graphic areas, and multiple dotted lines; the inner and outer diameter contours of the first graphic area are aligned with the inner and outer diameter contours of the grating code pattern; the second graphic area is a projection of the readhead's contour, and the multiple dotted lines are arranged in pairs along the radial direction of the transparent mounting pad; multiple readheads, each set within a corresponding second graphic area; the thickness of the transparent mounting pad matches the reading gap width of the readheads; the transparent mounting pad can be torn off along the dotted lines. This invention is used for the assembly and adjustment of multi-readhead sensors.

Description

Technical Field

[0001] This invention relates to an assembly and adjustment device and method for a multi-reading head circular grating sensor, belonging to the field of precision angle measurement technology. Background Technology

[0002] With the development of science and technology, increasingly higher demands are being placed on the measurement accuracy of circular grating angle sensors. In practical applications, the measurement accuracy of circular grating angle sensors is limited by installation and shaft system, resulting in a significant reduction in the system accuracy of the equipment. Besides manufacturing errors in the grating itself, the main sources of angle measurement error are installation errors and shaft system errors. Installation errors and shaft system errors include installation eccentricity, tilt, and shaft wobble, among which installation eccentricity error has the greatest impact on angle measurement accuracy.

[0003] In engineering practice, the common method to eliminate installation eccentricity errors is to use dual reading heads for diameter alignment. This method involves installing two reading heads at the diaphragm disk alignment position (with the reading signals phased out of phase). The principle is as follows: the reading error caused by eccentricity at a certain position is equal in magnitude but opposite in sign to the error caused by reading in the diametrical direction. Theoretically, the eccentricity error can be eliminated by simply adding the two readings and dividing by 2. In applications requiring higher accuracy in angle measurement, four, eight, or even more diametrically mounted reading heads are typically used to compensate for installation eccentricity errors.

[0004] The installation position of the radially mounted reading head is the most critical factor affecting the accuracy of the angle measurement sensor. Especially in applications with multiple reading heads, there are strict requirements for the signal amplitude, center bias voltage, signal orthogonality, and phase information of the radially mounted reading for each reading head. Ultimately, the accuracy is affected by human factors, and the installation and debugging process requires professional technicians to complete it through repeated and complicated operations. Summary of the Invention

[0005] This invention provides an assembly and adjustment device and method for a multi-reading head circular grating sensor, which can solve the problems of complex operation and difficulty in ensuring high-precision angle measurement requirements in existing installation and debugging processes.

[0006] On one hand, the present invention provides an assembly and adjustment device for a multi-readhead circular grating sensor, the device comprising:

[0007] Install the hub and connect it to the rotating spindle of the device under test;

[0008] A circular grating code disk is connected to the mounting hub, and its upper surface is coaxially provided with an annular grating code pattern.

[0009] A transparent mounting pad is disposed on the circular grating code disk, and has an annular first graphic area, multiple second graphic areas, and multiple dotted lines thereon; the inner and outer diameter contours of the first graphic area are aligned with the inner and outer diameter contours of the grating code track pattern; the second graphic area is the contour projection pattern of the reading head, and the multiple dotted lines are arranged in pairs along the radial direction of the transparent mounting pad.

[0010] Multiple reading heads correspond one-to-one with multiple second graphic areas, and the multiple second graphic areas are respectively distributed at the target installation position of the corresponding reading head. Each reading head is set in the corresponding second graphic area; the top of the reading head is fixedly connected to the fixed part of the device under test.

[0011] The thickness of the transparent mounting pad matches the width of the reading gap between the reading head and the circular grating code disk; the transparent mounting pad can be removed by tearing along the break line.

[0012] Optionally, the device further includes:

[0013] A video microscope is mounted on the transparent mounting pad, with the first graphic area and the raster track graphic located within the field of view of the video microscope.

[0014] Optionally, the device further includes:

[0015] Multiple mounting plates correspond one-to-one with multiple reading heads, and the top of each reading head is fixed to the fixed part of the device under test via the corresponding mounting plate.

[0016] Optionally, the device further includes:

[0017] Multiple fixing tapes are distributed on the outer edge of the transparent mounting pad to adhere the outer edge of the transparent mounting pad to the circular grating code disk.

[0018] Optionally, the thickness of the transparent mounting pad is 0.5mm to 1mm.

[0019] Optionally, the outer diameter of the transparent mounting pad is less than or equal to the outer diameter of the circular grating code disk.

[0020] Optionally, the transparent mounting pad is a transparent plastic sheet.

[0021] On the other hand, the present invention provides an assembly and adjustment method for an assembly and adjustment device based on any of the above-described multi-readhead circular grating sensors, the method comprising:

[0022] S1. Prepare transparent mounting gaskets;

[0023] S2. Fix the circular grating code disk to the mounting hub, and connect the mounting hub to the rotating spindle of the device under test;

[0024] S3. Fix the transparent mounting pad on the circular grating code disk, and align the first graphic area on the transparent mounting pad with the inner and outer rings of the grating code pattern on the circular grating code disk;

[0025] S4. Connect the tops of multiple reading heads to the fixed part of the device under test, and the bottom of each reading head contacts the transparent mounting pad and is located in the corresponding second graphic area;

[0026] S5. Apply force radially outward along the transparent mounting pad so that the transparent mounting pad can be torn and removed along the break line.

[0027] Optionally, S1 specifically includes:

[0028] Cut a transparent plastic sheet to obtain a gasket substrate, and use a pressing tool to create dotted lines on the gasket substrate;

[0029] The gasket substrate is cleaned and degreased using chemical reagents.

[0030] A metal film layer is prepared on the pad substrate, and a first pattern area and multiple second pattern areas are formed on the pad substrate using optical lithography to form a transparent mounting pad.

[0031] Optionally, the melting point of the transparent plastic sheet is greater than or equal to 80°C.

[0032] The beneficial effects that this invention can produce include:

[0033] The assembly and adjustment device for a multi-readhead circular grating sensor provided by this invention ensures the radial position of each readhead relative to the grating code track pattern on the circular grating disk, the relative position of multiple readheads, and the reading gap by using the first and second graphic areas on the transparent mounting pad and the thickness of the transparent mounting pad. This achieves high-precision and rapid installation and positioning of multiple readheads. This invention eliminates the complex installation and debugging process, removes the influence of human factors on the accuracy of the multi-readhead circular grating angle sensor, and greatly reduces the professional requirements for installation technicians. Compared with existing multi-readhead angle sensor installation and debugging devices, the assembly and adjustment device of this invention is easy to manufacture, low in cost, and applicable to the installation of conventional circular grating code disks both domestically and internationally, exhibiting strong versatility. Furthermore, the debugging method is simple and easy to implement, requiring low technical skills from operators, making it suitable for widespread adoption. Attached Figure Description

[0034] Figure 1 A schematic diagram of the assembly and adjustment device for a multi-reading-head circular grating sensor provided in an embodiment of the present invention;

[0035] Figure 2 for Figure 1 Exploded view;

[0036] Figure 3 This is a schematic diagram of the transparent mounting gasket structure provided in an embodiment of the present invention;

[0037] Figure 4 This is a schematic diagram of the gasket substrate structure provided in an embodiment of the present invention;

[0038] Figure 5 This is a schematic diagram of the circular grating code disk mounting structure provided in an embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram illustrating the alignment and fixing of the transparent mounting pad provided in an embodiment of the present invention;

[0040] Figure 7 This is a schematic diagram of the reading head installation and fixing provided in an embodiment of the present invention;

[0041] Figure 8 This is a schematic diagram showing the installation gasket after removal, as provided in an embodiment of the present invention.

[0042] Figure label:

[0043] 10. Rotary spindle; 20. Circular grating code disk; 21. Grating code track pattern; 30. Transparent mounting gasket; 31. Dotted line break; 32. First pattern area; 33. Second pattern area; 40. Mounting hub; 41. Connecting bolt; 50. Reading head; 60. Mounting plate; 70. Fixing tape; 80. Video microscope; 90. Dial indicator. Detailed Implementation

[0044] The present invention will now be described in detail with reference to the embodiments, but the present invention is not limited to these embodiments.

[0045] This invention provides an assembly and adjustment device for a multi-readhead circular grating sensor, such as... Figures 1 to 8 As shown, the device includes:

[0046] The hub 40 is installed and connected to the rotating spindle 10 of the device under test;

[0047] A circular grating code disk 20 is connected to a mounting hub 40, and an annular grating code pattern 21 is coaxially arranged on its upper surface.

[0048] A transparent mounting pad 30 is disposed on a circular grating code disk 20, and has an annular first graphic area 32, multiple second graphic areas 33, and multiple dotted lines 31. The inner and outer diameter contours of the first graphic area 32 are aligned with the inner and outer diameter contours of the grating code track pattern 21. The second graphic area 33 is the outline projection pattern of the reading head 50, and the multiple dotted lines 31 are arranged in pairs along the radial direction of the transparent mounting pad 30.

[0049] Multiple reading heads 50 correspond one-to-one with multiple second graphic areas 33. The multiple second graphic areas 33 are respectively distributed at the target installation positions of the corresponding reading heads 50, and each reading head 50 is set in the corresponding second graphic area 33. The top of the reading head 50 is fixedly connected to the fixed part of the device under test.

[0050] The thickness of the transparent mounting pad 30 matches the width of the reading gap between the reading head 50 and the circular grating code disk 20; the transparent mounting pad 30 can be removed by tearing along the dot break line 31.

[0051] Furthermore, the device also includes:

[0052] A video microscope 80 is mounted on a transparent mounting pad 30, with the first pattern area 32 and the grating code pattern 21 located within the field of view of the video microscope 80. The video microscope 80 is used to assist in aligning the inner and outer diameter contours of the first pattern area 32 with the inner and outer diameter contours of the grating code pattern 21 on the circular grating code disk 20.

[0053] In this invention, the device further includes:

[0054] Multiple mounting plates 60 correspond one-to-one with multiple reading heads 50, and the top of the reading head 50 is fixed to the fixed part of the device under test through the corresponding mounting plate 60.

[0055] Furthermore, the device also includes:

[0056] Multiple fixing tapes 70 are distributed on the outer edge of the transparent mounting pad 30 to bond the outer edge of the transparent mounting pad 30 to the circular grating disk 20.

[0057] In practical applications, the thickness of the transparent mounting pad 30 is the reading distance of the reading head 50, that is, the distance between the reading head 50 and the circular grating code disk 20. The thickness is generally about 0.5mm to 1.5mm, and its thickness tolerance is the allowable deviation of the reading distance, about ±0.1mm to ±0.3mm. The actual value depends on the technical requirements of the reading distance of the circular grating sensor.

[0058] The transparent mounting pad 30 is circular or annular in shape. Its outer diameter is equal to or slightly smaller than (<0.5mm ~3mm) the outer diameter of the circular grating code disk 20. If it is annular, its inner diameter should be slightly larger than or equal to the inner diameter of the circular grating code disk 20.

[0059] In this embodiment, there are 4 reading heads 50, which are installed in pairs with diametrical alignment. In practical applications, the number of reading heads 50 may be 2, 6, 8, or even more, and their arrangement is not limited to diametrical alignment. They may also be arranged at an optimized angle based on the angle measurement error compensation algorithm.

[0060] Reference Figure 3 As shown, the transparent mounting pad 30 is provided with multiple dotted lines 31, a first graphic area 32, and multiple second graphic areas 33. The first graphic area 32 is an annular shape, and its inner and outer diameters are consistent with the inner and outer diameters of the grating code pattern 21 on the circular grating code disk 20, so as to be aligned with the circular grating code disk 20 by the video microscope 80. The second graphic area 33 is the outline projection pattern of the reading head 50. In this embodiment, there are 4 second graphic areas 33, which are aligned in pairs.

[0061] The transparent mounting pad 30 has multiple break lines 31. When multiple reading heads 50 are installed, the transparent mounting pad 30 can be torn into two or more pieces under external force and removed radially along the circular grating disk 20.

[0062] Another embodiment of the present invention provides an assembly and adjustment method for an assembly and adjustment device based on any of the above-described multi-readhead circular grating sensors, the method comprising:

[0063] S1. Prepare transparent mounting pad 30.

[0064] Specifically, it includes:

[0065] (1) Cut the transparent plastic sheet to obtain the gasket substrate, and make the dotted line 31 on the gasket substrate using a pressing tool; wherein the melting point of the transparent plastic sheet is greater than or equal to 80°C.

[0066] Reference Figure 4 As shown, a certain thickness of high-melting-point transparent plastic sheet is taken and cut into a circle or ring. At the same time, a pressing tool is used to make a dotted break line 31. The transparency of the material is used to ensure that, in the subsequent installation steps, with the assistance of the video microscope 80, it can be aligned with the grating code pattern 21 on the circular grating code disk 20. The dotted break line 31 ensures that after the installation and debugging of the reading head 50 is completed, the transparent mounting pad 30 can be torn off with minimal force.

[0067] The thickness of the transparent mounting pad 30 is 0.5mm to 1mm, determined by the reading gap of the reading head 50. In this embodiment, the reading gap is 0.7mm, so the thickness is 0.7mm. The transparent plastic sheet is required to have a melting point greater than 80℃ to ensure that it will not deform during the subsequent surface metal film coating. In this embodiment, the material selected is transparent PET material (polyethylene terephthalate), which has a melting point greater than 250℃.

[0068] (2) Use chemical reagents to clean and degrease the gasket substrate.

[0069] Based on the material of the transparent plastic substrate, appropriate chemical reagents, such as alcohol, isopropanol, and deionized water, are selected to clean and degrease the gasket substrate, ensuring the quality of the film layer and its adhesion to the substrate in subsequent coating processes.

[0070] In this embodiment, alcohol can be used in an ultrasonic cleaner to remove oil and dirt from the gasket substrate, followed by cleaning with deionized water and drying, in order to proceed with the next coating process.

[0071] (3) A metal film layer is prepared on the pad substrate, and a first pattern area 32 and a plurality of second pattern areas 33 are formed on the pad substrate using optical photolithography to form a transparent mounting pad 30.

[0072] A metal film with a thickness of 80nm~1μm is prepared on a pad substrate. It is required to be opaque to the naked eye. The film preparation process is chemical plating, magnetron sputtering, electron beam evaporation, etc. The metal is copper, aluminum, chromium, nickel or stainless steel, etc.

[0073] In this embodiment, magnetron sputtering is used to sputter a metal film layer onto the cleaned pad substrate. Chromium is selected as the sputtering metal, and the thickness is 100nm~150nm.

[0074] Patterns are created on the pad substrate using optical lithography. The optical lithography process includes steps such as coating, photolithography, development, etching, and resist removal and cleaning on the pad substrate. The transparent mounting pad 30 contains two sets of patterns. The first pattern area 32 is an annular pattern area, and its inner and outer diameters are the same as the inner and outer diameters of the grating code pattern 21 in the circular grating code disk 20. The second pattern area 33 is a projection pattern of the outline of the reading head 50, and its position is the projection of the ideal mounting position of the reading head 50 onto the circular grating code disk 20.

[0075] S2. Fix the circular grating code disk 20 to the mounting hub 40, and connect the mounting hub 40 to the rotating spindle 10 of the device under test.

[0076] Reference Figure 1 and Figure 5 As shown, in this embodiment, the circular grating code disk 20 is first pasted onto the mounting hub 40, and the mounting hub 40 is connected to the rotating spindle 10 of the device under test by four connecting bolts 41.

[0077] It should be noted that the circular grating code disk 20 can be fixed to the mounting hub 40 by gluing or using a pressure plate. During the debugging process, the connecting bolt 41 between the mounting hub 40 and the rotating spindle 10 of the device under test should not be loosened. Use a dial indicator 90 to test the coaxiality of the circular grating code disk 20 and the rotating spindle 10. Generally, the radial runout should be adjusted to below 5 micrometers before tightening the connecting bolt 41 to fix it.

[0078] S3. Fix the transparent mounting pad 30 onto the circular grating code disk 20, and align the first graphic area 32 on the transparent mounting pad 30 with the inner and outer rings of the grating code pattern 21 on the circular grating code disk 20.

[0079] Reference Figure 1 and Figure 6 As shown, in this embodiment, the bottom surface (the side other than the graphic area) of the transparent mounting pad 30 is brought into contact with the circular grating code disk 20. Under the field of view of the video microscope 80, its position is adjusted so that the inner and outer diameter contours of the first graphic area 32 on the transparent mounting pad 30 are respectively aligned with the inner and outer diameters of the grating code pattern 21 on the circular grating code disk 20. Then, the transparent mounting pad 30 is fixed to the circular grating code disk 20 using the fixing tape 70.

[0080] It should be noted that, for ease of fixation, the inner diameter of the transparent mounting pad 30 is generally slightly larger than the inner diameter of the circular grating code disk 20, and the outer diameter of the transparent mounting pad 30 is slightly smaller than the outer diameter of the circular grating code disk 20; after fixation, remove the video microscope 80.

[0081] S4. Connect the tops of the multiple reading heads 50 to the fixed part of the device under test, and the bottom of each reading head 50 contacts the transparent mounting pad 30 and is located in the corresponding second graphic area 33.

[0082] Reference Figure 1 and Figure 7 As shown, first fix each reading head 50 onto the mounting plate 60. Note that, for ease of adjustment, the mounting plate 60 is not connected to the fixed part of the device under test at first. Then, using the second graphic area 33 on the transparent mounting pad 30 as a reference, place the bottom surface of the reading head 50 into the outline of the second graphic area 33. Finally, connect the mounting plate 60 to the fixed part of the device under test using fixing bolts.

[0083] It should be noted that during installation, the bottom surface of the reading head 50 contacts the transparent mounting pad 30 to ensure the reading gap; the relative positions of the multiple reading heads 50 are determined by the second graphic area 33 on the transparent mounting pad 30.

[0084] S5. Apply radial outward force along the transparent mounting gasket 30 so that the transparent mounting gasket 30 can be torn and removed along the break line 31.

[0085] After the reading head 50 is installed, radial force is applied along the transparent mounting gasket 30, causing the transparent mounting gasket 30 to tear along the break line 31, thereby removing the transparent mounting gasket 30. Figure 8 As shown.

[0086] It should be noted that, in order to facilitate tearing the transparent mounting pad 30, the number of cut lines 31 should generally be 4 or more.

[0087] The assembly and adjustment device for a multi-readhead circular grating sensor provided by this invention uses the first graphic area 32, the second graphic area 33 on the transparent mounting pad 30, and the thickness of the transparent mounting pad 30 to respectively ensure the radial position of each reading head 50 relative to the grating code pattern 21 on the circular grating code disk 20, the relative position of multiple reading heads 50, and the reading gap, thereby achieving high-precision and rapid installation and positioning of multiple reading heads 50. This invention eliminates the complex installation and debugging process, removes the influence of human factors on the accuracy of the multi-readhead circular grating angle sensor, and greatly reduces the professional requirements of installation technicians for circular grating sensors. Compared with existing multi-readhead angle sensor installation and debugging devices, the assembly and adjustment device of this invention is easy to manufacture, low in cost, and applicable to the installation of conventional circular grating code disks 20 both domestically and internationally, with strong versatility; at the same time, the debugging method is simple and easy to implement, with low technical requirements for operators, making it suitable for large-scale promotion.

[0088] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. An assembly and adjustment device for a multi-readhead circular grating sensor, characterized in that, The device includes: Install the hub and connect it to the rotating spindle of the device under test; A circular grating code disk is connected to the mounting hub, and its upper surface is coaxially provided with an annular grating code pattern. A transparent mounting pad is disposed on the circular grating code disk, and has an annular first graphic area, multiple second graphic areas, and multiple dotted lines thereon; the inner and outer diameter contours of the first graphic area are aligned with the inner and outer diameter contours of the grating code track pattern; the second graphic area is the contour projection pattern of the reading head, and the multiple dotted lines are arranged in pairs along the radial direction of the transparent mounting pad. Multiple reading heads correspond one-to-one with multiple second graphic areas, and the multiple second graphic areas are respectively distributed at the target installation position of the corresponding reading head. Each reading head is set in the corresponding second graphic area; the top of the reading head is fixedly connected to the fixed part of the device under test. The thickness of the transparent mounting pad matches the width of the reading gap between the reading head and the circular grating code disk; the transparent mounting pad can be removed by tearing along the break line.

2. The apparatus according to claim 1, characterized in that, The device further includes: A video microscope is mounted on the transparent mounting pad, with the first graphic area and the raster track graphic located within the field of view of the video microscope.

3. The apparatus according to claim 1, characterized in that, The device further includes: Multiple mounting plates correspond one-to-one with multiple reading heads, and the top of each reading head is fixed to the fixed part of the device under test via the corresponding mounting plate.

4. The apparatus according to claim 1, characterized in that, The device further includes: Multiple fixing tapes are distributed on the outer edge of the transparent mounting pad to adhere the outer edge of the transparent mounting pad to the circular grating code disk.

5. The apparatus of claim 1, wherein, The thickness of the transparent mounting pad is 0.5mm to 1mm.

6. The apparatus of claim 1, wherein, The outer diameter of the transparent mounting pad is less than or equal to the outer diameter of the circular grating code disk.

7. The apparatus of claim 1, wherein, The transparent mounting pad is a transparent plastic sheet.

8. An assembly and adjustment method for an assembly and adjustment device based on any one of claims 1 to 7 of a multi-readhead circular grating sensor, characterized in that, The method includes: S1. Prepare transparent mounting gaskets; S2. Fix the circular grating code disk to the mounting hub, and connect the mounting hub to the rotating spindle of the device under test; S3. Fix the transparent mounting pad on the circular grating code disk, and align the first graphic area on the transparent mounting pad with the inner and outer rings of the grating code pattern on the circular grating code disk; S4. Connect the tops of multiple reading heads to the fixed part of the device under test, and the bottom of each reading head contacts the transparent mounting pad and is located in the corresponding second graphic area; S5. Apply force radially outward along the transparent mounting pad so that the transparent mounting pad can be torn and removed along the break line.

9. The method of claim 8, wherein, S1 specifically includes: Cut a transparent plastic sheet to obtain a gasket substrate, and use a pressing tool to create dotted lines on the gasket substrate; The gasket substrate is cleaned and degreased using chemical reagents. A metal film layer is prepared on the pad substrate, and a first pattern area and multiple second pattern areas are formed on the pad substrate using optical lithography to form a transparent mounting pad.

10. The method of claim 9, wherein, The melting point of the transparent plastic sheet is greater than or equal to 80°C.

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