Encoder grating eccentric adjustment tool structure design method

Abstract

The invention discloses an encoder grating eccentric adjustment tool structure design method, which comprises a main body, a rotating shaft, a grating, a high-precision module, a photoelectric contact probe, a clamping cylinder, a push rod, a high-definition camera and a servo motor, and is characterized in that the grating is located at the outer side of the rotating shaft, the rotating shaft is connected with the main body, the high-precision module is located at the outer side of the main body, and the photoelectric contact probe is connected with the high-definition camera. The high-precision module is arranged in the X direction and the Y direction, the photoelectric contact probe is located on the outer side of the main body, the clamping air cylinder is located on one side of the main body, and the push rod is located on the high-precision module. The invention belongs to the technical field of grating encoder adjustment, and particularly solves the problems that traditional grating eccentricity adjustment has high skill requirements on workers and large errors, the distance between a grating and the grating is difficult to control, and the grating is easy to damage. And the encoder grating eccentric adjustment tool structure design method solves the problem that the precision of an encoder grating machining and assembling mechanism cannot meet actual requirements.

Description

Technical Field

[0001] The invention belongs to the technical field of grating encoder adjustment, and in particular refers to a design method for a tooling structure for adjusting eccentricity of an encoder grating. 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 initial adjustment benchmark is inconsistent due to the error in the encoder shape. In addition, the distance between the actual position of the push rod and the grating cannot be determined, 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 in order to save costs. This leads to the use of mature mechanical positioning methods without reference surface positioning. Even if the outer surface is processed, the error between the encoder grating and the center of the rotating spindle is relatively small, and the accuracy of the processing and assembly mechanism is difficult to meet the actual needs. Summary of the invention

[0007] The technical problem to be solved by the present invention is that the traditional method of adjusting the eccentricity of the grating by manual tapping combined with rotating images requires high skills of workers and has large errors. The traditional push rod pushes the grating, and it is difficult to control the distance between the push rod and the grating, which can easily damage the grating. There is a parallel error between the push rod axis and the original grating axis. Horizontal pushing causes the grating to deviate from the predetermined position. The accuracy of the encoder grating processing and assembly mechanism cannot meet actual needs.

[0008] In order to achieve the above functions, the technical solution adopted by the present invention is as follows: an encoder grating eccentricity adjustment tool, including a main body, a rotating shaft, a grating, a high-precision module, a photoelectric contact probe, a clamping cylinder, a push rod, a high-definition camera and a servo motor. The grating is located outside the rotating shaft, and the rotating shaft is connected to the main body. The high-precision module is located outside the main body, and the high-precision module is arranged in the X and Y directions. The photoelectric contact probe is located outside the main body, and the clamping cylinder is located on one side of the main body. The push rod is located on the high-precision module. By correcting the push rod with the photoelectric contact probe, not only can the current distance between the push rod and the grating be accurately measured to prevent the push rod from being displaced too much and damaging the grating edge, but also the push rod axis can be accurately moved to the axis corresponding to the current grating tangent point by correcting the push rod axis to prevent the bias error caused when moving the grating due to excessive parallel distance and angle errors of the axis.

[0009] The present invention also includes a design method and process for a tooling structure of an encoder grating eccentricity adjustment:

[0010] (1) After the components consisting of the main body, rotating spindle, and grating are moved to a fixed position, a clamping cylinder is used to fix the main body to prevent the movement of components during adjustment from causing the coordinate system to fail.

[0011] (2) The photoelectric contact probe uses the four-point centering principle to confirm the rotation center. During the movement of the photoelectric contact probe, a servo motor is used to keep the rotating spindle rotating, so that the rotation center obtained is more accurate.

[0012] (3) Similarly, use the four-point centering principle to confirm the position of the grating center in the rotating spindle coordinate system.

[0013] (4) Move the 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 point axis, and then use the grating center coordinates, push rod coordinates and the coordinate difference of the rotation spindle origin to command the push rod to complete the eccentricity adjustment. The grating correction adopts X and Y direction adjustment. Do not adopt a single direction combined with a 180-degree rotation adjustment to reduce the offset caused by the rotation axis angle error.

[0014] (5) After the adjustment is completed, a high-definition camera can be used to capture local images and combine them 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.

[0015] Preferably, the high-precision module is calibrated by a laser interferometer when moving.

[0016] Preferably, the photoelectric contact probe is set with a precision of 1 micron to ensure calibration accuracy.

[0017] Preferably, 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.

[0018] The present invention adopts the above structure to achieve the following beneficial effects:

[0019] 1. The present invention can accurately confirm the rotation center of the rotating shaft by adopting the four-point centering method. The grating center also adopts the four-point centering method to determine the coordinate system position of the rotating shaft, with high accuracy and small error.

[0020] 2. The present invention uses a laser interferometer to adjust the high-precision module, which can accurately adjust the push rod on the high-precision module, thereby avoiding the phenomenon that the push rod pushes the grating and causes the grating to deviate from the position or be damaged due to the axis of the push rod not being parallel to the grating. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A top view position relationship diagram of a design method for a tooling structure for adjusting the eccentricity of an encoder grating according to the present invention;

[0022] Figure 2 It is a main view position relationship diagram of a design method of a tooling structure for adjusting the eccentricity of an encoder grating of the present invention;

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

[0024] Figure 4 The present invention is a schematic diagram of the four-point centering principle of a design method for a tooling structure for adjusting the eccentricity of an encoder grating.

[0025] Among them, 1. Main body, 2. Rotating axis, 3. Grating, 4. High-precision module, 5. Photoelectric contact probe, 6. Clamping cylinder, 7. Push rod, 8. High-definition camera, 9. Servo motor. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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.

[0027] like Figure 1-4The present invention discloses an encoder grating eccentricity adjustment tool, comprising a main body 1, a rotating shaft 2, a grating 3, a high-precision module 4, a photoelectric contact probe 5, a clamping cylinder 6, a push rod 7, a high-definition camera 8 and a servo motor 9. The grating 3 is located outside the rotating shaft 2, and the rotating shaft 2 is connected to the main body 1. The high-precision module 4 is located outside the main body 1. The high-precision module 4 is arranged in the X and Y directions. When the high-precision module 4 moves, it is corrected by a laser interferometer. 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.

[0028] The high-precision module 4 is divided into X and Y directions. Take the adjustment of the X direction of movement as an example: the Y direction movement module is fixed to the machine table with screws, carrying the X direction movement module for translation. In order to increase rigidity and stability, the sliding mode of the high-precision module 4 adopts a zero-gap guide rail combination.

[0029] The X-direction module adopts a support to connect with the push rod 7 to realize driving the push rod 7 to translate in the X direction. The Y-direction module mainly carries the entire mechanism to adjust the contact point position relationship between the push rod 7 and the grating 3. The Y movement direction is consistent with the X movement direction structure connection.

[0030] The photoelectric contact probe 5 is located on the outside of the main body 1. The photoelectric contact probe 5 is set with an accuracy of 1 micron to ensure the accuracy of correction. The photoelectric contact probe 5 is placed on the top with a truss mechanism, and an X, Y bidirectional high-precision module 4 is used to collect the position relationship between the grating 3 and the push rod 7 in the coordinate system with the center of the rotating spindle as the origin. The clamping cylinder 6 is located on one side of the main body 1, and the push rod 7 is located on the high-precision module 4. By correcting the push rod 7 with the photoelectric contact probe 5, not only can the current distance between the push rod 7 and the grating 3 be accurately measured to prevent the push rod 7 from being displaced too much and damaging the edge of the grating 3, but also the axis of the push rod 7 can be accurately moved to the axis corresponding to the tangent point of the grating 3 at the current stage by correcting the axis, so as to prevent the offset error caused when moving the grating 3 due to excessive parallel distance and angle errors of the axis.

[0031] When used specifically, the following methods and processes are included:

[0032] (1) After the components consisting of the main body 1, the rotating spindle, and the grating 3 are moved to a fixed position, the main body 1 is fixed by a clamping cylinder 6 to prevent the movement of the components during the adjustment process from causing the coordinate system to fail.

[0033] (2) The photoelectric contact probe 5 uses the four-point centering principle to confirm the rotation center. During the movement of the photoelectric contact probe 5, the servo motor 9 is used to keep the rotation spindle rotating, so that the rotation center obtained is more accurate.

[0034] (3) Similarly, use the four-point centering principle to confirm the position of the center of grating 3 in the rotating spindle coordinate system.

[0035] (4) The photoelectric contact probe 5 collects the position information of the axis of the push rod 7 and the coordinates of the end face of the push rod 7. Combined with the previous center coordinates of the grating 3, the push rod 7 is first moved to the axis of the tangent point of the grating 3. Then, the coordinate difference between the center coordinates of the grating 3, the coordinates of the push rod 7 and the origin of the rotating spindle is used to command the push rod 7 to complete the eccentricity adjustment. The grating 3 is corrected by adjusting in the X and Y directions. 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.

[0036] (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.

[0037] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A method for designing a tooling structure for adjusting the eccentricity of an encoder grating, characterized in that: It includes a main body, a rotating shaft, a grating, a high-precision module, a photoelectric contact probe, a clamping cylinder, a push rod, a high-definition camera and a servo motor. The grating is located outside the rotating shaft, the rotating shaft is connected to the main body, the high-precision module is located outside the main body, the high-precision module is arranged in the X and Y directions, the photoelectric contact probe is located outside the main body, the clamping cylinder is located on one side of the main body, and the push rod is located on the high-precision module; The present invention also includes a design method and process for a tooling structure of an encoder grating eccentricity adjustment: (1) After the components consisting of the main body, rotating spindle, and grating are moved to a fixed position, a clamping cylinder is used to fix the main body to prevent the movement of components during adjustment from causing the coordinate system to fail. (2) The photoelectric contact probe uses the four-point centering principle to confirm the rotation center. During the movement of the photoelectric contact probe, a servo motor is used to keep the rotating spindle rotating, so that the rotation center obtained is more accurate. (3) Similarly, use the four-point centering principle to confirm the position of the grating center in the rotating spindle coordinate system. (4) Move the 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 point axis, and then use the grating center coordinates, push rod coordinates and the coordinate difference of the rotation spindle origin to command the push rod to complete the eccentricity adjustment. The grating correction adopts X and Y direction adjustment. Do not adopt a single direction combined with a 180-degree rotation adjustment to reduce the offset caused by the rotation axis angle error. (5) After the adjustment is completed, a high-definition camera can be used to capture local images and combine them 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.

2. The method for designing a tooling structure for adjusting the eccentricity of an encoder grating according to claim 1, characterized in that: The high-precision module is calibrated by a laser interferometer when moving.

3. The method for designing a tooling structure for adjusting the eccentricity of an encoder grating according to claim 1, characterized in that: The photoelectric contact probe is set with a precision of 1 micron.

4. The method for designing a tooling structure for adjusting the eccentricity of an encoder grating according to claim 1, characterized in that: 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.

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