Encoder grating eccentricity adjusting device and use method

Abstract

The invention discloses an encoder grating eccentricity adjusting device, an encoder comprises a main body, a rotating shaft and a grating, the rotating shaft and the main body are assembled and fixed, the grating surrounds the rotating shaft, and the encoder grating eccentricity adjusting device is characterized by comprising a high-precision module, a photoelectric contact measuring head, a clamping cylinder, a high-definition camera and a servo motor, the high-precision module is located on the outer side of the main body and arranged in the X direction and the Y direction, the high-precision module is provided with a push rod, the servo motor controls the rotating shaft to rotate, the clamping air cylinder and the photoelectric contact measuring head are located on the outer side of the main body, and the high-definition camera is located on the top of the high-precision module. The method has the advantages that the rotating center of the rotating shaft can be accurately confirmed through the four-point centering method, the grating circle center also adopts the four-point centering method to determine the coordinate system position of the rotating shaft, accuracy is high, and errors are small. The laser interferometer is adopted to correct the translation straightness of the high-precision module, so that the phenomenon of grating translation bias caused by large straightness error when the push rod moves is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of encoder grating eccentricity adjustment devices, and in particular to an encoder grating eccentricity adjustment device. Background Art

[0002] Grating encoders are important components in industrial production, playing an irreplaceable role in light industries such as textiles and bicycle manufacturing, as well as heavy industries such as machine tools and shipbuilding. Grating encoders are mainly composed of main body, grating, rotating shaft, printed circuit board and other parts. Among them, the concentricity error between the rotating main shaft and the grating is an important technical indicator to measure the accuracy of the encoder, and it is also an important process in the actual production of the encoder.

[0003] In the prior art, the encoder grating eccentricity adjustment methods and defects include:

[0004] 1. At present, most encoders are usually adjusted by manual tapping combined with the method of rotating images in actual production. This method not only requires high skills of workers, but also restricts the realization of unmanned assembly and manufacturing of encoders.

[0005] 2. The push rod is combined with the correction algorithm and the high-definition camera to adjust the eccentricity, such as Figure 3 The drawback of this method is that the error in the encoder shape causes the initially set adjustment reference to be inconsistent. In addition, the distance between the actual position of the push rod and the grating cannot be determined due to the inconsistent grating position, resulting in the push rod blindly pushing and damaging the grating. Secondly, if a high-definition camera is used to shoot the full frame to determine the position relationship, the image clarity and recognition are not high due to the large image, and accurate positioning cannot be achieved (the encoder concentricity error is usually ≦0.01mm). If a high-definition camera is used to shoot only a local area to improve the image quality, the original grating and the rotating spindle have too large a concentric deviation, resulting in the loss of the image-related alignment line or a large amount of correction calculation, resulting in the push rod being unable to correct the concentricity for a considerable period of time. In addition, if Figure 3 As shown, the axis of the push rod has a parallel error with the original axis of the grating, and when the grating is pushed horizontally, it will also cause the grating to deviate from the predetermined position.

[0006] 3. The main parts of most encoder products on the market are sandblasted, and only the specific photoelectric component installation position is processed, and the outer surface of the main body is almost not processed, mainly to save manufacturing costs. This results in the use of common mechanical positioning methods without reference surface positioning. Even if the outer surface processing is highly accurate due to the concentricity of the encoder grating and the rotating spindle center, the processing and assembly accuracy is difficult to meet actual needs. Summary of the invention

[0007] The purpose of the present invention is to provide an encoder grating eccentricity adjustment device to solve the problems raised in the above background technology.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0009] The present invention discloses an encoder grating eccentricity adjustment device, wherein the encoder comprises a main body, a rotating shaft, and a grating, wherein the rotating shaft is fixedly assembled with the main body, and the grating surrounds the rotating shaft. The invention is characterized in that the adjustment device comprises a high-precision module, a photoelectric contact probe, a clamping cylinder, a high-definition camera, and a servo motor, wherein the high-precision module is located on the outside of the main body and is arranged in the X and Y directions, the high-precision module is provided with a push rod, the servo motor controls the rotation of the rotating shaft, the clamping cylinder and the photoelectric contact probe are located on the outside of the main body, and the high-definition camera is located on the top of the high-precision module.

[0010] A method for using an encoder grating eccentricity adjustment device comprises the following steps:

[0011] Step 1: After the components consisting of the main body, rotating axis, and grating are moved to a fixed position, the main body is fixed with a clamping cylinder to prevent the movement of components during the adjustment process from causing the coordinate system to fail;

[0012] Step 2: Use a high-definition camera to take pictures and preliminarily determine which quadrant the eccentricity is in. This adjustment sets the eccentricity to be in the first quadrant. If it is in other quadrants, the rotating shaft can be rotated to adjust the eccentricity to the quadrant where the push rod adjustment range is located;

[0013] Step 3: Similarly, use the four-point centering principle to confirm the position of the grating center in the rotation axis coordinate system;

[0014] Step 4: Move the photoelectric contact probe to collect the position information of the push rod axis and the coordinates of the push rod end face. Combined with the previous grating center coordinates, first move the push rod to the grating tangent axis, and then use the grating center coordinates, push rod coordinates and the coordinate difference of the rotation axis origin to command the push rod to complete the eccentricity adjustment. The grating correction adopts X and Y direction adjustment, and do not adopt a single direction combined with rotation adjustment to reduce the offset caused by the rotation axis angular error.

[0015] Step 5. After the adjustment is completed, you can use a high-definition camera to take a local image and combine it with a correction algorithm. This can not only verify the accuracy of the eccentricity adjustment, but also, even if there is an eccentricity error, the error value is very small, and the final eccentricity adjustment can be completed quickly.

[0016] As an improvement, the high-precision module is corrected for straightness by a laser interferometer when it moves.

[0017] As an improvement, the photoelectric contact probe is set to have an accuracy of 1 micron.

[0018] As an improvement, the high-precision module adopts a linear motor translation stage with a positioning accuracy of ±0.25 microns and a repeat positioning accuracy of ±0.15 microns.

[0019] The advantages of the present invention over the prior art are: the rotation center of the rotating shaft can be accurately confirmed by adopting the four-point centering method, and the grating circle center also adopts the four-point centering method to determine the coordinate system position of the rotating shaft, with high accuracy and small error. By using a laser interferometer to perform translational straightness correction on the high-precision module, a large straightness error when the push rod moves can be avoided, which causes the grating translation offset phenomenon, and the operation is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings listed below are only some structural schematic diagrams of the present invention, not all of them.

[0021] Figure 1 The utility model is a top view of an encoder grating eccentricity adjustment device of the present invention.

[0022] Figure 2 The present invention is a front view of an encoder grating eccentricity adjustment device.

[0023] Figure 3 This is a schematic diagram of the error between the traditional push rod axis and the grating axis.

[0024] Figure 4 The invention discloses a four-point centering principle diagram of an encoder grating eccentricity adjustment device.

[0025] Figure 5 The present invention discloses a quadrant diagram of an encoder grating eccentricity adjustment device.

[0026] Reference numerals:

[0027] Main body 1; rotating shaft 2; grating 3; high-precision module 4; photoelectric contact probe 5; clamping cylinder 6; push rod 7; high-definition camera 8; servo motor 9. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In the description of the embodiments of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0030] In addition, if the terms "first", "second", "third", etc. appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance. If the terms "horizontal", "vertical", "overhanging", etc. appear, it does not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and it does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the embodiments of the present invention, if the terms "multiple" or "several" appear, they represent at least two.

[0032] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] This embodiment combines the attached Figures 1 to 5 , an encoder grating eccentricity adjustment device is described in detail.

[0034] The present embodiment provides an encoder grating eccentricity adjustment device, the encoder comprising a main body 1, a rotating shaft 2, and a grating 3, the rotating shaft 2 is assembled and fixed to the main body 1, and the grating 3 surrounds the rotating shaft 2, and is characterized in that the adjustment device comprises a high-precision module 4, a photoelectric contact probe 5, a clamping cylinder 6, a high-definition camera 8 and a servo motor 9, the high-precision module 4 is located on the outside of the main body 1 and is arranged in the X and Y directions, the high-precision module 4 is provided with a push rod 7, the servo motor 9 controls the rotation of the rotating shaft 2, the clamping cylinder 6 and the photoelectric contact probe 5 are located on the outside of the main body 1, and the high-definition camera 8 is located on the top of the high-precision module 4.

[0035] A method for using an encoder grating eccentricity adjustment device comprises the following steps:

[0036] Step 1: After the components consisting of the main body 1, the rotating shaft 2, and the grating 3 are moved to a fixed position, the main body 1 is fixed with a clamping cylinder 6 to prevent the movement of the components during the adjustment process from causing the coordinate system to fail;

[0037] Step 2, use the high-definition camera 8 to shoot and preliminarily determine which quadrant the eccentricity is in. This adjustment sets the eccentricity to be in the first quadrant. If it is in other quadrants, the rotating shaft 2 can be rotated to adjust the eccentricity to the quadrant where the push rod 7 is adjusted; (The purpose of this process is to save manufacturing costs. If this step is omitted, it is necessary to add high-precision module adjustments in four directions, which increases manufacturing costs);

[0038] Step 3: Similarly, use the four-point centering principle to confirm the position of the center of the grating 3 in the coordinate system of the rotating axis 2;

[0039] Step 4, move the photoelectric contact probe 5 to collect the position information of the axis of the push rod 7 and the end face coordinates of the push rod 7, combine the previous coordinates of the center of the grating 3, first move the push rod 7 to the axis of the tangent point of the grating 3, and then use the coordinate difference between the center of the grating 3, the coordinates of the push rod 7 and the origin of the rotating axis 2 to command the push rod 7 to complete the eccentricity adjustment. The grating 3 is corrected by adjusting in the X and Y directions, and do not adopt a single direction combined with a 180-degree rotation adjustment to reduce the offset caused by the angular error of the rotating axis 2;

[0040] Step 5: After the adjustment is completed, the high-definition camera 8 can be used to capture a local image and combine it with a correction algorithm, which can not only verify the accuracy of the eccentricity adjustment, but also, even if there is an eccentricity error, the error value is very small, and the final eccentricity adjustment can be completed quickly.

[0041] The high-precision module 4 is corrected for straightness by a laser interferometer when it moves.

[0042] The photoelectric contact probe 5 is set to have an accuracy of 1 micron.

[0043] The high-precision module 4 adopts a linear motor translation stage with a positioning accuracy of ±0.25 microns and a repeat positioning accuracy of ±0.15 microns.

[0044] During the specific implementation, just follow the above steps.

[0045] The present invention and its embodiments are described above, and such description is not restrictive, and the actual protection scope is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An encoder grating eccentricity adjustment device, the encoder comprising a main body (1), a rotating shaft (2), and a grating (3), the rotating shaft (2) and the main body (1) are assembled and fixed, and the grating (3) surrounds the rotating shaft (2), characterized in that: The adjustment device comprises a high-precision module (4), a photoelectric contact probe (5), a clamping cylinder (6), a high-definition camera (8) and a servo motor (9); the high-precision module (4) is located outside the main body (1) and is arranged in the X and Y directions; the high-precision module (4) is provided with a push rod (7); the servo motor (9) controls the rotation of the rotating shaft (2); the clamping cylinder (6) and the photoelectric contact probe (5) are located outside the main body (1); and the high-definition camera (8) is located on the top of the high-precision module (4).

2. The method for using the encoder grating eccentricity adjustment device according to claim 1, characterized in that: The following steps are involved: Step 1: After the components consisting of the main body (1), the rotating shaft (2) and the grating (3) are moved to a fixed position, the main body (1) is fixed using a clamping cylinder (6) to prevent the movement of the components during the adjustment process from causing the coordinate system to fail; Step 2, use a high-definition camera (8) to take pictures and preliminarily determine which quadrant the eccentricity is in. This adjustment sets the eccentricity to be in the first quadrant. If it is in other quadrants, the rotating shaft (2) can be rotated to adjust the eccentricity to the quadrant where the push rod (7) is within the adjustment range. Step 3: Similarly, use the four-point centering principle to confirm the position of the center of the grating (3) in the coordinate system of the rotating axis (2); Step 4, move the photoelectric contact probe (5) to collect the axis position information of the push rod (7) and the end face coordinates of the push rod (7), combine the previous center coordinates of the grating (3), first move the push rod (7) to the axis of the tangent point of the grating (3), and then use the coordinate difference between the center coordinates of the grating (3), the coordinates of the push rod (7) and the origin coordinates of the rotation axis (2) to command the push rod (7) to complete the eccentricity adjustment. The grating (3) is corrected by adjusting in the X and Y directions, and a single direction combined with a 180-degree rotation adjustment is not adopted to reduce the offset caused by the angular error of the rotation axis (2); Step 5: After the adjustment is completed, a high-definition camera (8) can be used to take a local image and combine it with a correction algorithm. This can not only verify the accuracy of the eccentricity adjustment, but also, even if there is an eccentricity error, the error value is very small, and the final eccentricity adjustment can be completed quickly.

3. The method for using the encoder grating eccentricity adjustment device according to claim 1, characterized in that: The high-precision module (4) performs straightness correction via a laser interferometer when moving.

4. The method for using the encoder grating eccentricity adjustment device according to claim 1, characterized in that: The photoelectric contact probe (5) is set to have a precision of 1 micron.

5. The method for using the encoder grating eccentricity adjustment device according to claim 1, characterized in that: The high-precision module (4) adopts a linear motor translation stage with a positioning accuracy of ±0.25 microns and a repeat positioning accuracy of ±0.15 microns.

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