WO2020215205A1 - 一种光栅盘及反馈*** - Google Patents

一种光栅盘及反馈*** Download PDF

Info

Publication number
WO2020215205A1
WO2020215205A1 PCT/CN2019/083896 CN2019083896W WO2020215205A1 WO 2020215205 A1 WO2020215205 A1 WO 2020215205A1 CN 2019083896 W CN2019083896 W CN 2019083896W WO 2020215205 A1 WO2020215205 A1 WO 2020215205A1
Authority
WO
WIPO (PCT)
Prior art keywords
grating
zero
encoders
encoder
feedback system
Prior art date
Application number
PCT/CN2019/083896
Other languages
English (en)
French (fr)
Inventor
丁兵
秦红燕
潘继汉
谭元芳
吴荣波
高云峰
Original Assignee
大族激光科技产业集团股份有限公司
深圳市大族思特科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 大族激光科技产业集团股份有限公司, 深圳市大族思特科技有限公司 filed Critical 大族激光科技产业集团股份有限公司
Priority to PCT/CN2019/083896 priority Critical patent/WO2020215205A1/zh
Priority to CN201980004907.6A priority patent/CN111279158A/zh
Priority to DE112019004545.8T priority patent/DE112019004545T5/de
Priority to JP2020535089A priority patent/JP2021524015A/ja
Priority to US16/995,847 priority patent/US20200378804A1/en
Publication of WO2020215205A1 publication Critical patent/WO2020215205A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/347—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
    • G01D5/3473—Circular or rotary encoders
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/347—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
    • G01D5/34707—Scales; Discs, e.g. fixation, fabrication, compensation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/347—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
    • G01D5/34776—Absolute encoders with analogue or digital scales
    • G01D5/34792—Absolute encoders with analogue or digital scales with only digital scales or both digital and incremental scales
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/36—Forming the light into pulses
    • G01D5/38—Forming the light into pulses by diffraction gratings
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • H02K11/21—Devices for sensing speed or position, or actuated thereby
    • H02K11/22—Optical devices

Definitions

  • the invention relates to the field of galvanometers, in particular to a grating disc and a feedback system, which can be applied to the angle detection of a galvanometer motor.
  • the guiding control of laser or other scanning signals is mainly realized by a rotating motor that can reciprocate within a certain range or angle to drive a mirror.
  • This kind of motor that can drive the mirror to swing at high speed and high precision is usually called a galvanometer motor.
  • This motor is different from ordinary motors. It can only swing within a certain angle because it cannot rotate once. Therefore, during the movement, the zero mark of the main grating must appear in the field of view of the encoder. And because it controls the deflection angle of the lens used to reflect light, it has extremely high requirements for accuracy and responsiveness.
  • the final positioning accuracy of light or other signals on the surface to be measured or processed is directly related to the accuracy of mirror swing. And because the longer the distance from the mirror to the processed surface, the greater the magnification of the mirror swing error, so the higher the positioning accuracy of the mirror is required.
  • one end of the rotating shaft of the galvanometer motor is directly connected to the reflector, and the other end is directly connected to the encoder that feedbacks the motor position.
  • the encoder that feedbacks the motor position.
  • the technical problem to be solved by the present invention is to provide a grating disc and a feedback system in view of the above-mentioned defects of the prior art, which can solve the problem that the rotating shaft will rotate due to the shaking of the rotating shaft, or under the influence of different temperature, vibration and environment. The center drifts to cause the problem that the accuracy of the mirror is affected.
  • the technical solution adopted by the present invention to solve its technical problem is to provide a grating disc, the grating disc is provided with a main grating and a zero grating arranged close to the main grating at different diameter positions, and the zero grating is provided with 2N
  • the 2N zero-position gratings are uniformly angularly distributed around the center of the grating disc; where N is a positive integer.
  • the main grating includes a plurality of notches arranged in an annular area/arc area with equal widths and equal intervals.
  • the zero-position grating includes a plurality of notches arranged at unequal intervals in an arc-shaped area.
  • the width of the notches is not all equal.
  • the zero-position grating includes a plurality of notches arranged in an arc-shaped area, and the widths of the notches are set to be non-equal.
  • a preferred solution is: all the zero-position gratings are the same; or, part or all of the zero-position gratings are different.
  • the zero-position grating includes a first zero-position grating and a second zero-position grating arranged at positions of different diameters.
  • the technical solution adopted by the present invention to solve its technical problem is to provide a feedback system applied to a rotating body, including: a grating disk fixed on the rotating body, the center of the grating disk is the same as the rotating shaft of the rotating body Shaft setting; 2N encoders, 2N said encoders are uniformly angularly distributed with the center of the grating disc, and obtain the position of the corresponding zero grating to identify the zero position, and obtain the position change of the main grating to identify the rotation angle; wherein, N is a positive integer; the processing unit obtains the zero position of all encoders feedback to realize the positioning of the corresponding encoder; obtains the rotation angles of all encoders feedback, and calculates the average rotation angle to confirm the actual rotation angle of the grating disc.
  • the photoelectric receiving end of the encoder is provided with a zero position window group
  • the zero position window group includes alternately arranged transparent windows and opaque windows, the positions of the opaque windows are The notch matching of the zero grating.
  • a preferred solution is that part or all of the zero gratings are different, and each of the encoders is paired with a zero grating.
  • the feedback system further includes a signal processing circuit
  • the signal processing circuit includes a filter module, a sampling module, an arithmetic module, and a signal output module arranged in sequence
  • the filter module is connected to the encoder
  • the The processing unit is connected with the signal output module.
  • the rotating body is the rotating shaft of the galvanometer motor, and the center of the rotating shaft of the galvanometer motor is coaxially arranged with the center of the grating disc.
  • the beneficial effect of the present invention is that, compared with the prior art, the present invention can be used with multiple encoders by designing a grating disc, and a feedback system is provided to increase the detection accuracy and stability of the grating disc and the encoder, especially in In the galvanometer motor system, the anti-eccentricity and drift resistance of the galvanometer motor system is improved, thereby improving the environmental tolerance and anti-interference ability of the galvanometer motor; further, the difficulty of assembly and adjustment can be reduced. Unqualified products are also easier to detect.
  • Fig. 1 is a schematic diagram of the principle of the concentricity error of the grating disc of the present invention
  • FIG. 2 is a schematic diagram of the principle of drift error of the grating disk of the present invention.
  • Figure 3 is a schematic diagram of the structure of the grating disc of the present invention.
  • Fig. 4 is an enlarged schematic diagram of part A of Fig. 3;
  • FIG. 5 is a schematic diagram of the structure of the first type of zero-position grating of the present invention.
  • FIG. 6 is a schematic diagram of the structure of the second type of zero-position grating of the present invention.
  • FIG. 7 is a schematic diagram of the structure of the third type of zero-position grating of the present invention.
  • FIG. 8 is a schematic diagram of the structure of a grating disc based on four zero-position gratings of the present invention.
  • FIG. 9 is a schematic diagram of the structure of a grating disc based on eight zero-position gratings of the present invention.
  • Figure 10 is a schematic structural diagram of the feedback system of the present invention.
  • FIG. 11 is a schematic diagram of the structure of the feedback system based on the signal processing circuit of the present invention.
  • Figure 12 is a schematic structural diagram of the feedback system based on four encoders of the present invention.
  • Figure 13 is a schematic structural diagram of a feedback system based on eight encoders of the present invention.
  • FIG. 14 is a schematic diagram of the principle of the concentricity error compensation of the grating disc of the present invention.
  • Fig. 15 is a schematic diagram of the principle of reducing drift error of the grating disc of the present invention.
  • the invention provides a grating disc and a feedback system, which can solve the problems of encoder accuracy and radial shaking of the rotating shaft.
  • the encoder there are two ways to improve the accuracy of the encoder.
  • One is to adjust the concentricity and end jump of the encoder through assembly, so that the ideal rotation center coincides with the actual rotation center as much as possible.
  • the main grating and photoelectric receiver The relative distance of the device is fixed, which can improve the positioning accuracy; but based on a certain installation and adjustment equipment, there is an upper limit for its accuracy improvement.
  • the second is to increase the number of engraved lines of the encoder circular grating, increase the resolution and electronic subdivision magnification to improve the overall accuracy.
  • the shaking of the rotating shaft during the movement will also affect the rotation accuracy of the mirror.
  • the rotation of the shaft in the motor cannot be separated from the cooperation of the bearing, and there is a certain gap between the balls and the track inside the bearing. This will result in a certain amount of radial shaking in the final actual rotation of the rotating shaft, and these shaking will also affect the rotation accuracy of the mirror.
  • the rotation center of the rotating shaft will drift. These drifts will eventually affect the repeatability of the mirror.
  • FIG. 1 is a schematic diagram showing the error of the concentricity of the grating disk 10 and the rotation center.
  • Point A in FIG. 1 is the ideal center point and the rotation center of the grating disk 10, and the two coincide, and A'is the actual rotation center caused by the assembly or processing technology.
  • the optical radius d is 10mm.
  • the grating disk 10 rotates around the ideal rotation center A, and the arc length L read by the encoder 20 is as follows Formula calculation:
  • the grating disk 10 will rotate around A'point with different concentricity.
  • the arc length L1 read by the encoder 20 is:
  • Figure 2 is a schematic diagram of the drift error of the rotation center.
  • the ideal rotation center is point A, but due to the gap between the bearings, the actual rotation center will be caused by factors such as temperature and vibration. Drifted to point A'.
  • the reading of the encoder 20 changes due to the drift of the center of rotation.
  • the arrow Q in the figure is the increasing direction of the reading of the encoder 20. Then when the rotation center drifts from A to A', the reading of the encoder 20 will become smaller, which will cause the value of the position feedback system to drift.
  • the present invention provides a preferred embodiment of a grating disc.
  • a grating disc 200 is provided with a main grating 210 and a zero grating 220 arranged close to the main grating 210 at different diameter positions.
  • the zero grating 220 is provided with 2N and 2N zeros
  • the grating 220 has a uniform angular distribution around the center 201 of the grating disk; where N is a positive integer.
  • the main grating 210 and the zero grating 220 do not overlap; and, the concept of the notch described below, involving words such as distance, pitch, and width, can be regarded as the displacement between the centers of the notches or the arc path distance, It can also be the displacement or distance obtained by other measurement methods.
  • the shape of the grating disk 200 is usually round but not limited to a circle.
  • the grating disk 200 can be set to be a rectangle, and only a notch is provided in the wobble area.
  • the substrate is removed together, wherein the substrate is the body of the grating disc 200, and the code track is arranged on the substrate.
  • the ring or arc structure formed by the main grating 210 and the zero grating 220 is set with the center 201 of the grating disk as the center.
  • the grating disc 200 includes a glass body, and a large number of notches are carved on the glass body.
  • the notches are opaque parts, and the gap between the two notches is smooth. Part can be light-transmissive; among them, the scores can be metal plating or other scores.
  • the main grating 210 includes a plurality of notches arranged at equal widths and equal intervals in an annular area.
  • the distance between the width and pitch is the grating pitch, which is usually 20um or 40um, which can also be considered as the arc track distance of the centerline;
  • the grating disk 200 is provided with a circle of the main grating 210, and the center of the main grating 210 is the center 201 of the grating disk.
  • the main grating 210 includes a plurality of notches arranged in an arc-shaped area with equal widths and equal intervals, which are consistent with the above description, but are arranged in an arc shape, and preferably can extend to both sides based on the zero grating 220 as the center. Set up.
  • the length of the arc-shaped area may depend on the application environment of the grating disc, that is, the angle of round-trip rotation.
  • the zero-position grating 220 includes a plurality of notches arranged at unequal intervals in an arc-shaped area, that is, the width of each notch and the width of the area between adjacent notches together form a "code” ", as long as the width of the notch or the width of the adjacent area is changed, a new "code” can be formed, where the "code” is the unique identification code of the zero grating 220, which is an ID card belonging to the "code” number. Referring to FIG.
  • the zero grating 220 includes a plurality of notches arranged at unequal intervals in an arc-shaped area, and at the same time, the widths of the notches are the same; referring to FIG. 6, the zero grating 220 includes A plurality of notches are arranged at unequal intervals in an arc-shaped area, and at the same time, the widths of the notches are not all equal, that is, part of the notches is equal, or all of them are not equal.
  • the zero-position grating 220 includes a plurality of notches arranged in an arc-shaped area, and the widths of the notches are set not to be equal; there are two possibilities here, the first is The pitches of the scores are equal, and the second is that the pitches of the scores are not all equal.
  • the zero position grating 220 includes a first zero position grating 221 and a second zero position grating 222 arranged at different diameter positions, and subsequent encoding can be further optimized through the first zero position grating 221 and the second zero position grating 222 The positioning accuracy of the device reduces external interference.
  • the examples adopted by the first zero-position grating 221 and the second zero-position grating 222 can refer to the examples of the above-mentioned solution 1 and solution 2.
  • a "code” is constructed by the zero-position grating 220, and various possible studies can be carried out on the setting of the "code”. Since the grating disc 200 of the present invention is preferably applied to achieve reciprocating motion and rotation angle In a small special environment, it is necessary to set different "codes" on a grating disc 200 to prevent transitional rotation of the grating disc 200. For example, part or all of the zero-position gratings 220 are not the same. The difference here means that the "codes" are different. Preferably, when N is greater than 1, the "codes" of adjacent zero-position gratings 220 are different; for example, all The zero-position gratings are all the same. The same here means the same "code”.
  • N is equal to 1
  • the grating disk 200 rotates the zero-position grating 220 to the diagonal, which is more difficult. Large, and there is no need to adopt a different "coding" method.
  • N there are four zero gratings 220 on the grating disk 200, that is, N is 2, and the angle of each zero grating 220 is 90 degrees.
  • N there are zero gratings 220, that is, N is 4, and the included angle of each zero grating 220 is 45 degrees.
  • the present invention provides a preferred embodiment of a feedback system.
  • a feedback system is applied to a rotating body and includes a grating disk 200, an encoder 400 and a processing unit 500; wherein the grating disk 200 is fixed on the rotating body, and the center of the grating disk 200 (ie, the center of the grating disk) 201) Coaxially arranged with the rotating shaft of the rotating body, the number of encoders 400 is set to 2N, the 2N encoders 400 are uniformly angularly distributed with the center 201 of the grating disc, and the position of the corresponding zero grating 220 is obtained to identify the zero position, And obtain the position change of the main grating 210 to identify the rotation angle; where N is a positive integer.
  • the center of the rotation axis of the galvanometer motor is coaxially arranged with the center of the grating disc 200 (ie, the grating disc center 201), because the galvanometer motor can only be set at one angle Inner swing, usually ⁇ 12.5°, then the galvanometer motor needs to swing the shaft back and forth to drive the grating disc 200 to swing below the encoder 400 and make the encoder 400 find its own zero position respectively, and then the encoder 400 can start to work normally and record The rotation angle of the grating disc 200.
  • the readings of the two encoders 400 in the same group will be one larger and the other small. After averaging, the actual rotation angle of the grating disk 200 will be compensated to correct the single The reading caused by the encoder 400 is too large or too small. And, when the rotation axis is displaced due to external reasons, the reading of the encoder 400 will cause one reading to increase and one reading to decrease. After the readings of the two encoders 400 in the same group are averaged, the final The reading is reset to zero, which greatly reduces the influence of the rotation center offset on the result.
  • the photoelectric receiving end of the encoder 400 is provided with a zero position window group
  • the zero position window group includes alternately arranged transparent windows and opaque windows, the position of the opaque window and the zero grating The nicks match. Since the galvanometer motor has the characteristic of only swinging and not being able to rotate one circle, it is necessary to separately set a zero position signal at the position where each encoder 400 is installed, so that the zero position of each encoder 400 can be found after being powered on.
  • the photoelectric receiving end of the encoder 400 is provided with a main grating window group.
  • the main grating window group also includes alternately arranged light-transmitting windows and opaque windows, and light-transmitting windows and opaque windows Set for equal width.
  • each encoder 400 relative to the grating disc 200 must be kept consistent to ensure that when the grating disc 200 rotates in a certain direction, the readings of all the encoders 400 keep changing in the same direction, that is, increase or decrease at the same time. There must be no increase or decrease.
  • the value of the output signal of the encoder 400 is digitally added and averaged, and the sum of the readings of all the encoders 400 is accumulated as A, and divided by the total number of encoders 400 2N to obtain the final galvanometer motor
  • the angle of rotation ⁇ is as follows:
  • the zero window of the encoder 400 is set directly above/just below the zero code channel 220.
  • the grating disc 200 includes a glass body, and a large number of notches are carved on the glass body.
  • the notches are opaque parts, and the smooth part between the two notches can transmit light; wherein
  • the encoder 400 is a transmissive encoder 400.
  • the grating disk 200 includes a metal body, and a large number of notches are carved on the surface of the metal body.
  • the smooth metal surface between the two notches can reflect light; wherein, the encoder 400 is a reflective encoder 400.
  • the light source emits parallel light of a certain waveband, and after the light is transmitted vertically, it is captured by the photoelectric receiver on the other side, and finally forms interference moire fringes and converted into electrical signals.
  • a light source emits a certain wavelength of parallel light, which is incident on a smooth metal surface at a certain angle, is reflected by the smooth metal surface at a certain angle, and is finally captured by a photoelectric receiver on the same side of the light source Form an electrical signal.
  • the light source of the transmissive encoder 400 is a light emitting diode LED
  • the light source of the reflective encoder 400 is a laser diode LD.
  • the rotating body is the rotating shaft of the galvanometer motor.
  • the light passes through the mirror swing to change the propagation direction and finally reaches the surface of the processed or detected object.
  • the installation accuracy of the galvanometer motor encoder 400, the encoder 400 grating disc 200 and the photoelectric receiving component The precision of the processing and production process, the radial shaking and drift generated when the motor shaft rotates, will affect the rotation accuracy of the mirror, and the mirror rotation error will be further amplified by the reflected optical path, which will cause the processing beam or measuring beam to reach the target.
  • the position of the surface of the processed object has a significant deviation from the predetermined position.
  • the multi-encoder 400 works together, and the galvanometer motor multi-encoding special grating disc 200 is redesigned to ensure that each encoder 400 can correctly identify the zero position in the swing condition, and then the encoder 400 is placed on the same grating according to a specific position
  • the disk 200 is supplemented by a specific algorithm to reduce the position error in the final output and reduce the influence of eccentricity, radial sway and drift.
  • the present invention provides a preferred embodiment of a signal processing circuit.
  • the feedback system also includes a signal processing circuit 600, which includes a filter module 610, a sampling module 620, an arithmetic module 630, and a signal output module 640 arranged in sequence.
  • the filter module 610 is connected to the encoder 400, so The processing unit 500 is connected to the signal output module 640.
  • the output signal of the encoder 400 may be an analog sine cosine signal, a square wave ABZ signal, a pulse signal, a digital protocol signal, etc.
  • the signal is filtered, sampled, and calculated, and then the final position is output through the signal output module.
  • the output signal also includes analog, digital protocol, square wave ABZ and other types of signals, and the final signal passes the signal
  • the transmission cable is transported to the back-end processing equipment such as the drive.
  • the output of the encoder 400 will be changed to an analog quantity, and the adjustment accuracy of the encoder 400 will be strictly controlled, so that the signal phases output by all the encoders 400 are the same, and they are superimposed in parallel Finally, the encoders 400 of all groups are output to the signal processing circuit 600 at the same time, the signals are filtered, collected, and the final position is calculated.
  • the signal processing circuit 600 can be a separate circuit board, or it can be integrated into the circuit board of the encoder 400, or it can be a circuit board integrating a driver; further, it can be used as the signal processing circuit 600
  • the algorithm of the processing circuit board can be calculated by a separate chip, can also be calculated by the main control chip of an external motor drive board, or by a chip built in the encoder 400.
  • signal processing methods include digital and analog.
  • Digital averaging is to add up all the encoder 400 readings and use the encoder 400 numbers to obtain the average value.
  • the analog averaging needs to strictly control the installation position of the encoder 400 in the same group, so that the analog sine and cosine signals obtained by the photoelectric receiver of the encoder 400 have the same phase and the same direction, which can completely form a superposition; finally, the superimposed signal of each group is input to the signal processing Circuit 600.
  • the present invention provides a preferred embodiment of multiple encoders.
  • each set of encoders 400 is two encoders 400 arranged symmetrically at 180 degrees, or more than two sets or even more encoders 400 may be arranged according to accuracy requirements.
  • the angle between the two encoders 400 in each group must meet the 180° requirement. If there are 2N encoders 400, the angle ⁇ between the encoders 400 satisfies the formula:
  • the present invention provides a preferred embodiment of the concentricity error compensation of the grating disk.
  • point A is the ideal center point and the rotation center of the grating disc 200, which are normally coincident, and A'is the actual rotation center caused by the assembly or processing technology.
  • the galvanometer motor 300 rotates a fixed angle ⁇ (set 25°)
  • the optical radius d is 10mm.
  • the grating disc 200 rotates around the point A'with different concentric degrees, assuming that the optical radius d1 is 12mm, the code
  • the arc length L1 read by the detector 410 is:
  • the learning radius d2 is 8mm, and the arc length L2 measured by the diagonal encoder 420 is:
  • the arc length L read by the encoder is calculated by the following formula:
  • the present invention provides a preferred embodiment for reducing drift errors of a grating disk.
  • the ideal rotation center is point A, but due to the gap between the bearings, the actual rotation center will be caused by factors such as temperature and vibration. Drifted to point A'.
  • the arrows Q1 and Q2 in the figure are the increasing directions of the encoder readings.
  • the center of rotation drifts from A to A', the reading of the encoder 410 will become smaller and the reading of the encoder 420 will become larger. Therefore, when only one encoder is installed, the value of the position feedback system will drift. But averaging the values of the two encoders (410, 420) will make the effects of increase and decrease cancel each other out, so that the final position data remains unchanged. This is related to the position of the two encoders specially arranged in the diameter direction.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Optical Transform (AREA)

Abstract

一种光栅盘及反馈***。光栅盘（200）在不同直径位置上设有主光栅（210）和靠近主光栅设置的零位光栅（220），零位光栅（220）设有2N个，2N个零位光栅（220）以光栅盘（200）中心呈均匀角度分布；其中，N为正整数。通过设计光栅盘，可配合多个编码器使用，以及设置反馈***，增加光栅盘及编码器的检测精度和稳定性，特别是在振镜电机***中，提高了振镜电机***的抗偏心和漂移的能力，从而提高了振镜电机对环境的耐受性和抗干扰能力。

Description

一种光栅盘及反馈*** 技术领域
本发明涉及振镜领域，具体涉及一种光栅盘及反馈***，可应用在振镜电机的角度检测中。
背景技术
在当前的激光加工领域和光扫描领域，对于激光或其他扫描信号的导向控制，主要是通过一种能在一定范围或夹角内往复运动的旋转电机带动一面镜子实现。这种可以带动镜子高速高精度摆动的电机通常被称作振镜电机。此电机与普通电机有所不同，其因为不能旋转一周而只能在某角度内摆动，因此在运动过程中，主光栅的零位刻痕必须出现在编码器视野内。又因为其控制的是用于反射光线的镜片偏转角，因此对精度和响应能力有极高的要求。
由于光线通过摆动镜面的反射后，再传播一个相当长的距离才能够到达被处理或被探测表面。因此，最终光或其他信号在被测或被处理表面的定位精度与镜面摆动的精度有直接关系。又因为光从镜面到被处理表面的距离越长，镜面摆动误差的放大倍率就会越大，所以对镜面的定位精度要求也就越高。
通常情况下，振镜电机的转轴一端与反射镜直接相连，另一端与反馈电机位置的编码器直接相连。要提高反射镜的定位精度和重复精度，就要提高编码器的精度。
另外，除了编码器对反射镜转动精度的影响，转轴在运动过程中的晃动也会对反射镜的转动精度产生影响。
鉴于此，需提供一种光栅盘及反馈***，可同时解决编码器精度和转轴径 向晃动的问题，以提高反射镜的转动精度。
发明内容
本发明要解决的技术问题在于，针对现有技术的上述缺陷，提供一种光栅盘及反馈***，解决现有由于转轴晃动，或者在不同温度，震动和环境的影响下，会使转轴的转动中心产生漂移，以导致反射镜的精度受到影响的问题。
本发明解决其技术问题所采用的技术方案是：提供一种光栅盘，所述光栅盘在不同直径位置上设有主光栅和靠近主光栅设置的零位光栅，所述零位光栅设有2N个，2N个所述零位光栅以光栅盘中心呈均匀角度分布；其中，N为正整数。
其中，较佳方案是：所述主光栅包括在一环形区域内/弧形区域内呈等宽等间距排列的多个刻痕。
其中，较佳方案是：所述零位光栅包括在一弧形区域内呈不等间隔排列的多个刻痕。
其中，较佳方案是：所述刻痕的宽度为非全相等设置。
其中，较佳方案是：所述零位光栅包括在一弧形区域内排列的多个刻痕，且所述刻痕的宽度为非全相等设置。
其中，较佳方案是：全部所述零位光栅均相同；或者，部分或全部所述零位光栅不相同。
其中，较佳方案是：所述零位光栅包括设置在不同直径位置上的第一零位光栅和第二零位光栅。
本发明解决其技术问题所采用的技术方案是：提供一种反馈***，应用在一旋转主体上，包括：固设在旋转主体上的光栅盘，所述光栅盘的中心与旋转 主体的转轴同轴设置；2N个编码器，2N个所述编码器以光栅盘中心呈均匀角度分布，并获取对应零位光栅的位置以识别零位，以及获取主光栅的位置变化以识别旋转角度；其中，N为正整数；处理单元，获取全部编码器反馈的零位，实现对应编码器的定位；获取全部编码器反馈的旋转角度，计算平均旋转角度以确认光栅盘的实际旋转角度。
其中，较佳方案是：所述编码器的光电接收端设有零位窗口组，所述零位窗口组包括交替设置的透光窗口和不透光窗口，所述不透光窗口的位置与零位光栅的刻痕匹配。
其中，较佳方案是：部分或全部所述零位光栅不相同，每一所述编码器均与一零位光栅配对。
其中，较佳方案是：所述反馈***还包括信号处理电路，所述信号处理电路包括依次设置的滤波模块、采样模块、运算模块和信号输出模块，所述滤波模块与编码器连接，所述处理单元与信号输出模块连接。
其中，较佳方案是：所述旋转主体为振镜电机的转轴，所述振镜电机的转轴中心与光栅盘的中心同轴设置。
本发明的有益效果在于，与现有技术相比，本发明通过设计光栅盘，可配合多个编码器使用，以及设置反馈***，增加光栅盘及编码器的检测精度和稳定性，特别是在振镜电机***中，以及提高了振镜电机***的抗偏心和漂移的能力，从而提高了振镜电机对环境的耐受性和抗干扰能力；进一步地，可以降低装调难度，对于装调不合格的产品也更容易检出。
附图说明
下面将结合附图及实施例对本发明作进一步说明，附图中：
图1是本发明光栅盘的同心度误差的原理示意图；
图2是本发明光栅盘漂移误差的原理示意图；
图3是本发明光栅盘的结构示意图；
图4是图3的A部分的放大结构示意图；
图5是本发明第一类零位光栅的结构示意图；
图6是本发明第二类零位光栅的结构示意图图；
图7是本发明第三类零位光栅的结构示意图；
图8是本发明基于四个零位光栅的光栅盘的结构示意图；
图9是本发明基于八个零位光栅的光栅盘的结构示意图；
图10是本发明反馈***的结构示意图；
图11是本发明基于信号处理电路的反馈***的结构示意图；
图12是本发明基于四个编码器的反馈***的结构示意图；
图13是本发明基于八个编码器的反馈***的结构示意图；
图14是本发明光栅盘的同心度误差补偿的原理示意图；
图15是本发明光栅盘消减漂移误差的原理示意图。
具体实施方式
现结合附图，对本发明的较佳实施例作详细说明。
本发明提供一种光栅盘及反馈***，可解决编码器精度和转轴径向晃动的问题。
一般而言，提高编码器精度的方法有二种，一种是通过装配，调整编码器的同心度，端跳等不理想情况，使理想旋转中心与实际旋转中心尽量重合，主光栅与光电接收器的相对距离固定，可以使定位精度有所提高；但是基于一定 的装调设备的前提下，其精度提高存在上限。第二种是通过增加编码器圆光栅的刻线数，增加分辨率与电子细分倍率提高整体精度。但是在光栅刻划工艺一定的前提下，增加刻线数就意味着必须增大圆光栅直径，而圆光栅直径的增加又带来了转动惯量的增加，从而影响振镜摆动的最高速度和加减速能力，因此也存在上限。所以，对于从编码器装调和设计精度方面着手提高振镜整体精度的方法，存在上限和瓶颈，如何在装配工艺和加工工艺一定的前提下进一步提高振镜电机产品的精度，成为了一个难题。
除了编码器对反射镜转动精度的影响，转轴在运动过程中的晃动也会对反射镜的转动精度产生影响。通常情况下，转轴在电机内的转动离不开轴承的配合，而轴承内部的滚珠和轨道的配合，存在一定的间隙。这就会导致转轴最后的实际转动存在一定的径向晃动，而这些晃动，同样会影响反射镜的转动精度。除了晃动，在不同温度，震动和环境的影响下，会使转轴的转动中心产生漂移，这些漂移，最终会导致反射镜的重复精度受到影响。
具体地，关于晃动问题，可参考图1，图1为光栅盘10与旋转中心同心度存在误差的示意图。图1中A点为理想的光栅盘10中心点和旋转中心，二者相重合，A’是因为组装或加工工艺导致的实际的旋转中心。当电机转动一个固定的角度θ(设25°)时，光学半径d为10mm，在理想情况下，光栅盘10绕理想旋转中心A旋转，则由编码器20读取到的弧长L由如下公式计算：
Figure PCTCN2019083896-appb-000001
但是，在实际测量中，光栅盘10会绕同心度不同的A’点进行旋转，假设光学半径d1为12mm，则由编码器20读取到的弧长L1为：
Figure PCTCN2019083896-appb-000002
由此可见，如果光栅盘10与旋转中心同心度存在误差的情况下，就会导致编码器20读出的距离不准，而继续按照理想的转动中心反推，就会导致最终测算电机转动角度存在较大偏差。
以及，关于漂移问题，可参考图2，图2为转动中心漂移误差发的示意图。假设在光栅盘10码道中心与转轴为理想的同心度情况下，理想的转动中心为A点，但由于轴承之间的配合存在缝隙，当因温度、震动等因素影响，导致实际的转动中心漂移到了A’点。那么电机在实际没有运动时，由于转动中心的漂移，导致编码器20的读数都有所变化。图中箭头Q是编码器20的读数增加方向。那么当转动中心由A漂移到A’时，编码器20读数会变小，会使位置反馈***的数值产生漂移。
如图3和图4所示，本发明提供一种光栅盘的优选实施例。
一种光栅盘200，所述光栅盘200在不同直径位置上设有主光栅210和靠近主光栅210设置的零位光栅220，所述零位光栅220设有2N个，2N个所述零位光栅220以光栅盘中心201呈均匀角度分布；其中，N为正整数。以及，主光栅210和零位光栅220不重叠；以及，下文描述的刻痕的概念，涉及到距离、间距、宽度等词汇，均可视为刻痕中心之间的位移或者弧形路径距离，也可以为其他测量方式所得到的位移或距离。
其中，光栅盘200的形状通常为圆形但不仅限于圆形，例如光栅盘200可以设置成长方形，仅在摆动区域内设置刻痕，对于外部编码器读不到的区域，可以连同码道和基底一同去除，其中，基底为光栅盘200的本体，码道设置在基底上。以及，主光栅210和零位光栅220所构成环形或弧形结构是以光栅盘中心201为圆心设置的。
首先，提供光栅盘200的两种设计方案，方案一、所述光栅盘200包括玻璃主体，在玻璃主体上刻出大量的刻痕，刻痕为不透光部分，两刻痕之间的光滑部分可以透光；其中，刻痕可为金属镀膜或其他刻划痕迹。方案二、所述光栅盘200包括金属主体，金属主体的表面上刻出大量的刻痕，两刻痕间的光滑金属面可以反射光；其中，也可以在玻璃主体镀上金属层形成金属主体。
其次，提供主光栅210的优选方案，并参考图4。方案一、主光栅210包括在一环形区域内呈等宽等间距排列的多个刻痕，宽度间距的距离为栅距，通常为20um或40um，也可以认为是中线的弧形轨迹距离；这样，光栅盘200设置了一圈主光栅210，且主光栅210的圆心即为光栅盘中心201。方案二、主光栅210包括在弧形区域内呈等宽等间距排列的多个刻痕，与上述描述一致，只是呈弧形设置，优选可根据零位光栅220为中心诶之向两侧延伸设置。并且，所述弧形区域的长短，可取决于光栅盘的应用环境，即往返旋转的角度。
以及，提供零位光栅220的优选方案，并参考图5至图7。方案一、所述零位光栅220包括在一弧形区域内呈不等间隔排列的多个刻痕，即每一刻痕的宽度以及相邻刻痕之间的区域的宽度共同构建出一“编码”，只要改变刻痕的宽度或相邻区域的宽度，就能形成新的“编码”，其中，所述“编码”是反应零位光栅220的唯一识别码，是属于“编码”的身份证号码。参考图5，所述零位光栅220包括在一弧形区域内呈不等间隔排列的多个刻痕，同时，所述刻痕的宽度均相同；参考图6，所述零位光栅220包括在一弧形区域内呈不等间隔排列的多个刻痕，同时，所述刻痕的宽度为非全相等设置，即部分相等，或者全部不相等。
方案二、可参考图7，所述零位光栅220包括在一弧形区域内排列的多个刻痕，且所述刻痕的宽度为非全相等设置；这里存在两种可能，第一是各刻痕 的间距相等，第二是各刻痕的间距不是全相等。
方案三、所述零位光栅220包括设置在不同直径位置上的第一零位光栅221和第二零位光栅222，通过第一零位光栅221和第二零位光栅222可以进一步优化后续编码器的定位精度，降低外部干扰。其中，所述第一零位光栅221和第二零位光栅222所采用的例子可参考上述方案一和方案二的例子。
在本实施例中，通过零位光栅220构建出一“编码”，可针对“编码”的设置问题进行各种可能性研究，由于本发明的光栅盘200优选应用在可实现往返运动且转动角度较小的特殊环境中，需要在一光栅盘200上设置不同的“编码”，防止光栅盘200的过渡转动。例如，部分或全部所述零位光栅220不相同，这里的不相同是指“编码”不同，优选为当N大于1时，相邻的零位光栅220的“编码”不同；再例如，全部所述零位光栅均相同，这里的相同是指“编码”相同，优选为当N等于1时，只存在两个零位光栅220，光栅盘200将零位光栅220旋转到对角，难度较大，并不需要采用不同的额“编码”方式。
对于需要继续提高编码器数量的情况，需要考虑电机实际的摆动角度与每个编码器实际工作角度的关系。如果电机摆动角度过大，会出现同一个零位光栅220可能在不同角度情况下出现在相邻的两个编码器上，对于这种情况需要更改每个或相邻两个零位光栅220的“编码”。
可参考图8，光栅盘200上设有4个零位光栅220，即N为2，且每一零位光栅220的夹角为90度，也可参考图9，光栅盘200上设有8个零位光栅220，即N为4，且每一零位光栅220的夹角为45度。
如图10所示，本发明提供反馈***的优选实施例。
一种反馈***，应用在一旋转主体上，包括光栅盘200、编码器400和处理单元500；其中，光栅盘200固设在旋转主体上，并且所述光栅盘200的中 心(即光栅盘中心201)与旋转主体的转轴同轴设置，编码器400设置为2N个，2N个所述编码器400以光栅盘中心201呈均匀角度分布，并获取对应零位光栅220的位置以识别零位，以及获取主光栅210的位置变化以识别旋转角度；其中，N为正整数。
以及，当旋转主体准备运行旋转时，特别如振镜电机，所述振镜电机的转轴中心与光栅盘200的中心(即光栅盘中心201)同轴设置，因为振镜电机只能在一个角度内摆动，通常为±12.5°，那么振镜电机需要来回摆动转轴，带动光栅盘200在编码器400下方摆动并使编码器400分别找到自己的零位，然后编码器400才能开始正常工作，记录光栅盘200的转动角度。
具体地，当光栅盘200出现偏心时，同一组的两个编码器400的读数会出现一个大一个小的情况，经过平均后，光栅盘200实际的转动角度就会被补偿出来，从而修正单个编码器400造成的读数偏大或偏小的情况。以及，当转轴因外部原因导致旋转中心产生位移时，编码器400的读数，会产生一个读数增大，一个读数减小的情况，经过同组两个编码器400读数平均后，可以使最终的读数归零，从而大大减弱旋转中心偏移对结果产生的影响。
进一步地，所述编码器400的光电接收端设有零位窗口组，所述零位窗口组包括交替设置的透光窗口和不透光窗口，所述不透光窗口的位置与零位光栅的刻痕匹配。由于振镜电机具有只摆动不能旋转一周的特性，因此需要在每个编码器400安装的位置单独设置零位信号，以使每个编码器400上电后都能找到零位。当然，所述编码器400的光电接收端设有主光栅窗口组，同理所述主光栅窗口组也包括交替设置的透光窗口和不透光窗口，并且，透光窗口和不透光窗口为等宽设置。
其中，每个编码器400相对于光栅盘200的放置方向需保持一致，保证当 光栅盘200沿某个方向转动时，所有编码器400的读数保持同向变化，即同时增加或同时减少。不可出现有增有减的情况。
关于处理单元500，将编码器400的输出信号的值进行数字量加和平均，累加所有编码器400读数的和为A，并除以编码器400的总数2N，用以得出最终振镜电机转动的角度Φ。公式如下：
Figure PCTCN2019083896-appb-000003
其中，所述编码器400的零位窗口设置在零码道220的正上方/正下方。
在本实施例中，所述光栅盘200包括玻璃主体，在玻璃主体上刻出大量的刻痕，刻痕为不透光部分，两刻痕之间的光滑部分可以透光；其中，所述编码器400为透射式编码器400。所述光栅盘200包括金属主体，金属主体的表面上刻出大量的刻痕，两刻痕间的光滑金属面可以反射光；其中，所述编码器400为反射式编码器400。具体地，关于透射式编码器400，其由光源发出某个波段的平行光线，垂直透光后，被另一侧的光电接收器捕获，并最终形成干涉摩尔条纹并转化为电信号。关于反射式编码器400，其由光源发出某个波段的平行光线，以一定角度入射至光滑金属面后，被光滑金属面以一定的角度反射，并最终被处于光源同一侧的光电接收器捕获形成电信号。优选地，透射式编码器400的光源为发光二极管LED，反射式编码器400的光源为激光二极管LD。
在本实施例中，所述旋转主体为振镜电机的转轴。
在激光加工或光信号扫描的过程中，光线通过反射镜摆动改变传播方向并最终到达被处理或被探测物体表面，振镜电机编码器400安装的精度，编码器400光栅盘200及光电接收组件的加工生产工艺精度，电机转轴转动时产生的径向晃动和漂移，都会影响到反射镜的转动精度，而反射镜转动误差经过反射光程的进一步放大，就会导致加工光束或测量光束到达被处理物体表面的位置与 预定位置产生明显偏差。
通过多编码器400共同工作，并重新设计振镜电机多编码专用光栅盘200，以确保摆动情况每个编码器400都能正确识别零位，再将编码器400按照特定位置放置于同一个光栅盘200上，辅以特定的算法，实现减小最终输出时的位置误差，减弱偏心，径向晃动漂移等方面的影响。
如图11所示，本发明提供信号处理电路的较佳实施例。
所述反馈***还包括信号处理电路600，所述信号处理电路600包括依次设置的滤波模块610、采样模块620、运算模块630和信号输出模块640，所述滤波模块610与编码器400连接，所述处理单元500与信号输出模块640连接。
编码器400的输出信号可以为模拟正余弦信号，方波ABZ信号，脉冲信号，数字协议信号等。信号处理电路600内，将信号进行滤波，采样，运算后，再通过信号输出模块将最终的位置进行输出，输出的信号亦包含模拟，数字协议，方波ABZ等类型的信号，最终信号通过信号传输电缆输送至驱动器等后端处理设备。
其中，对于模拟量加和法，会将编码器400的输出量更改为模拟量，并严格控制编码器400装调精度，使所有编码器400所输出的信号相位相同，并对他们进行并联叠加，最终将所有组的编码器400同时输信号处理电路600，经过信号滤波，采集，并计算最终位置。
在本实施例中，信号处理电路600可为单独的电路板，也可以将其整合在编码器400的电路板中，也可以为整合驱动器的电路板；进一步地，作为信号处理电路600的信号处理电路板的算法可由单独的芯片进行计算，也可由外部电机驱动板的主控芯片计算，或者由编码器400内置的芯片完成计算。
例如，信号处理的方式包含数字式和模拟式。数字式平均即将所有编码器400读数相加并处以编码器400个数，获得平均值。模拟式平均需要严格控制同组编码器400安装位置，使编码器400的光电接收器获得的模拟正余弦信号相位相同，方向相同，可以完全形成叠加；最后将每组的叠加信号输入至信号处理电路600。
如图12和图13所示，本发明提供多个编码器的较佳实施例。
通常情况下布置一组或两组编码器400，每一组编码器400均为呈180度对称设的两个编码器400，也可以根据精度需要布置两组以上甚至更多编码器400。每组的两个编码器400夹角必须满足180°要求。若共有2N个编码器400，则各编码器400之间的夹角θ满足公式：
Figure PCTCN2019083896-appb-000004
对于设置多个编码器400时，如果振镜的摆动角度大于360/4N的情况，可能会存在摆动范围内出现两个零位的风险。因此，还需要对应每个位置上的零位光栅220不同，以区分不同位置上的零位信号，防止摆动范围内出现多零位的问题。
如图14所示，本发明提供一种光栅盘的同心度误差补偿的较佳实施例。
图中A点为理想的光栅盘200中心点和旋转中心，正常情况二者相重合，A’是因为组装或加工工艺导致的实际的旋转中心。当振镜电机300转动一个固定的角度θ(设25°)时，光学半径d为10mm，当光栅盘200绕同心度不同的A’点进行旋转时，假设光学半径d1为12mm，则由编码器410读取到的弧长L1为：
Figure PCTCN2019083896-appb-000005
而学半径d2为8mm，对角的编码器420测得的弧长L2为：
Figure PCTCN2019083896-appb-000006
通过将L1与L2平均后，最终的弧长L’如下：
Figure PCTCN2019083896-appb-000007
其中，在理想情况下，光栅盘200中心点和旋转中心重合，圆光栅200绕理想旋转中心A旋转，则由编码器读取到的弧长L由如下公式计算：
Figure PCTCN2019083896-appb-000008
由此可见，对于振镜振镜电机300因光栅盘200同心度问题产生的误差，具有很好的抑制作用。
如图15所示，本发明提供一种光栅盘消减漂移误差的较佳实施例。
假设在光栅盘200码道中心与转轴为理想的同心度情况下，理想的转动中心为A点，但由于轴承之间的配合存在缝隙，当因温度、震动等因素影响，导致实际的转动中心漂移到了A’点。
若振镜电机300在实际没有运动时，由于转动中心的漂移，导致编码器410和编码器420的读数都有所变化。图中箭头Q1和Q2分别是编码器的读数增加方向。当转动中心由A漂移到A’时，编码器410读数会变小，编码器420读数会变大，因此当只装一个编码器时，就会使位置反馈***的数值产生漂移。但将两个编码器(410、420)的数值平均，就会使得增大和减小的影响相互抵消，使最终的位置数据保持不变。这与呈直径方向特殊布置的两个编码器位置有关。
对于特定某一方向的漂移，只有与这个方向向量垂直的那组对角线的两个编码器可以起最大作用。因此，如果需要消除多个方向的漂移，就需要多组编码器进行支持。由于，振镜电机300运动的特殊性，其只在固定某个角度(常见为±12.5°)内不停摆动而不会整圈转动，因此最少一组两个编码器即可大致消减漂移误差。
以上所述者，仅为本发明最佳实施例而已，并非用于限制本发明的范围，凡依本发明申请专利范围所作的等效变化或修饰，皆为本发明所涵盖。

Claims (12)

  1. 一种光栅盘，所述光栅盘在不同直径位置上设有主光栅和靠近主光栅设置的零位光栅，其特征在于：所述零位光栅设有2N个，2N个所述零位光栅以光栅盘中心呈均匀角度分布；其中，N为正整数。
  2. 根据权利要求1所述的光栅盘，其特征在于：所述主光栅包括在一环形区域内/弧形区域内呈等宽等间距排列的多个刻痕。
  3. 根据权利要求1所述的光栅盘，其特征在于：所述零位光栅包括在一弧形区域内呈不等间隔排列的多个刻痕。
  4. 根据权利要求3所述的光栅盘，其特征在于：所述刻痕的宽度为非全相等设置。
  5. 根据权利要求1所述的光栅盘，其特征在于：所述零位光栅包括在一弧形区域内排列的多个刻痕，且所述刻痕的宽度为非全相等设置。
  6. 根据权利要求1至5任一所述的光栅盘，其特征在于：全部所述零位光栅均相同；或者，部分或全部所述零位光栅不相同。
  7. 根据权利要求1至5任一所述的光栅盘，其特征在于：所述零位光栅包括设置在不同直径位置上的第一零位光栅和第二零位光栅。
  8. 一种反馈***，应用在一旋转主体上，其特征在于，包括：
    固设在旋转主体上且如权利要求1-7任一所述的光栅盘，所述光栅盘的中心与旋转主体的转轴同轴设置；
    2N个编码器，2N个所述编码器以光栅盘中心呈均匀角度分布，并获取对应零位光栅的位置以识别零位，以及获取主光栅的位置变化以识别旋转角度；其中，N为正整数；
    处理单元，获取全部编码器反馈的零位，实现对应编码器的定位；获取全 部编码器反馈的旋转角度，计算平均旋转角度以确认光栅盘的实际旋转角度。
  9. 根据权利要求8所述的反馈***，其特征在于：所述编码器的光电接收端设有零位窗口组，所述零位窗口组包括交替设置的透光窗口和不透光窗口，所述不透光窗口的位置与零位光栅的刻痕匹配。
  10. 根据权利要求9所述的反馈***，其特征在于：部分或全部所述零位光栅不相同，每一所述编码器均与一零位光栅配对。
  11. 根据权利要求8所述的反馈***，其特征在于：所述反馈***还包括信号处理电路，所述信号处理电路包括依次设置的滤波模块、采样模块、运算模块和信号输出模块，所述滤波模块与编码器连接，所述处理单元与信号输出模块连接。
  12. 根据权利要求8所述的反馈***，其特征在于：所述旋转主体为振镜电机的转轴，所述振镜电机的转轴中心与光栅盘的中心同轴设置。
PCT/CN2019/083896 2019-04-23 2019-04-23 一种光栅盘及反馈*** WO2020215205A1 (zh)

Priority Applications (5)

Application Number Priority Date Filing Date Title
PCT/CN2019/083896 WO2020215205A1 (zh) 2019-04-23 2019-04-23 一种光栅盘及反馈***
CN201980004907.6A CN111279158A (zh) 2019-04-23 2019-04-23 一种光栅盘及反馈***
DE112019004545.8T DE112019004545T5 (de) 2019-04-23 2019-04-23 Strichscheibe und rückkopplungssystem
JP2020535089A JP2021524015A (ja) 2019-04-23 2019-04-23 格子ディスク及びフィードバックシステム
US16/995,847 US20200378804A1 (en) 2019-04-23 2020-08-18 Grating disc and feedback system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2019/083896 WO2020215205A1 (zh) 2019-04-23 2019-04-23 一种光栅盘及反馈***

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US16/995,847 Continuation US20200378804A1 (en) 2019-04-23 2020-08-18 Grating disc and feedback system

Publications (1)

Publication Number Publication Date
WO2020215205A1 true WO2020215205A1 (zh) 2020-10-29

Family

ID=70999802

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/083896 WO2020215205A1 (zh) 2019-04-23 2019-04-23 一种光栅盘及反馈***

Country Status (5)

Country Link
US (1) US20200378804A1 (zh)
JP (1) JP2021524015A (zh)
CN (1) CN111279158A (zh)
DE (1) DE112019004545T5 (zh)
WO (1) WO2020215205A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114895422A (zh) * 2022-03-30 2022-08-12 中国船舶重工集团公司第七0七研究所 一种片式圆光栅的安装调整结构及安装调整方法

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112157635B (zh) * 2020-10-26 2023-12-15 中国工程物理研究院机械制造工艺研究所 一种双编码器式动态角度发生转台及使用方法
CN114846301B (zh) * 2020-12-01 2024-02-27 深圳市速腾聚创科技有限公司 光栅盘、z相信号的识别方法、光电编码器和激光雷达
CN113701880B (zh) * 2021-07-16 2022-12-09 南京大学 一种高光通量光谱编码成像***与方法
CN117949021A (zh) * 2024-03-26 2024-04-30 横川机器人（深圳）有限公司 双传感光电角度编码器的实现方法、编码器及介质

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000346676A (ja) * 1999-06-04 2000-12-15 Canon Inc 光学式ロータリーエンコーダ
CN2771823Y (zh) * 2005-02-05 2006-04-12 苏州一光仪器有限公司 绝对式角度编码器
CN101153808A (zh) * 2007-09-19 2008-04-02 苏州一光仪器有限公司 单码道绝对式角度编码度盘及采用该度盘的编码器

Family Cites Families (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2406804A1 (fr) * 1977-10-20 1979-05-18 Sercel Rech Const Elect Codeur angulaire a angle d'entree variable
JPS56143958A (en) * 1980-04-11 1981-11-10 Hitachi Ltd Rotating angle detector
JPH0621801B2 (ja) * 1985-07-03 1994-03-23 キヤノン株式会社 ロ−タリ−エンコ−ダ−
JPS6212814A (ja) * 1985-07-10 1987-01-21 Canon Inc ロ−タリ−エンコ−ダ−
DE3844704C2 (zh) * 1987-09-30 1992-06-17 Kabushiki Kaisha Okuma Tekkosho, Nagoya, Aichi, Jp
US5073710A (en) * 1989-09-21 1991-12-17 Copal Company Limited Optical displacement detector including a displacement member's surface having a diffractive pattern and a holographic lens pattern
JP2555083Y2 (ja) * 1991-12-24 1997-11-19 株式会社ニコン 回転角測定装置
JP3098358B2 (ja) * 1992-11-27 2000-10-16 三菱電機株式会社 位置検出素子、その位置検出素子を用いた位置検出方法、および光学式ロータリーエンコーダ
US6803560B1 (en) * 1999-06-10 2004-10-12 Canon Kabushiki Kaisha Optical encoder
JP2004212243A (ja) * 2003-01-06 2004-07-29 Canon Inc 格子干渉型光学式エンコーダ
CN100424540C (zh) * 2004-09-14 2008-10-08 中国科学院安徽光学精密机械研究所 大口径光学潜望式激光雷达三维扫描装置
CN2903908Y (zh) * 2006-04-12 2007-05-23 合肥工业大学 复合型高精度二维坐标零位标识***
CN101083423B (zh) * 2006-05-29 2010-07-14 深圳市大族精密机电有限公司 振镜电机
CN100425952C (zh) * 2006-10-10 2008-10-15 李苏 退化伪随机旋转传感器
EP2255158A4 (en) * 2008-03-10 2014-01-22 Timothy Webster DETECTION OF THE POSITION OF A PISTON IN A HYDRAULIC SPINDLE USING A PHOTOGRAPHIC IMAGE SENSOR
WO2009148066A1 (ja) * 2008-06-05 2009-12-10 三菱電機株式会社 光学式エンコーダ
CN201397147Y (zh) * 2008-12-19 2010-02-03 深圳市大族激光科技股份有限公司 分度***及其分度圆盘
JP2011021998A (ja) * 2009-07-15 2011-02-03 Canon Inc エンコーダ信号処理装置
JP5170046B2 (ja) * 2009-09-18 2013-03-27 株式会社安川電機 ロータリエンコーダ、ロータリモータ、ロータリモータシステム、ディスク及びロータリエンコーダの製造方法
CN101769765A (zh) * 2010-01-29 2010-07-07 江西蓝天学院 单码道结构的增量式光电编码器码盘
JP2011226986A (ja) * 2010-04-22 2011-11-10 Nikon Corp エンコーダ
WO2011152076A1 (ja) * 2010-05-31 2011-12-08 株式会社安川電機 ロータリエンコーダ、ロータリモータ及びロータリモータシステム
JP6486097B2 (ja) * 2014-12-19 2019-03-20 キヤノン株式会社 位置検出装置、レンズ装置、撮像システム、工作装置、位置検出方法、プログラム、および、記憶媒体
CN104613991B (zh) * 2015-03-06 2017-04-26 浙江琦星电子有限公司 一种编码器光栅盘及光电编码器
JP2016173287A (ja) * 2015-03-17 2016-09-29 キヤノン株式会社 検出装置
JP6474289B2 (ja) * 2015-03-19 2019-02-27 株式会社キーエンス 光学式ロータリーエンコーダ
CN205509783U (zh) * 2016-03-13 2016-08-24 鞍山精准光学扫描技术有限公司 一种基于光栅传感器的振镜马达
CN106404014B (zh) * 2016-11-23 2018-08-21 广州市精谷智能科技有限公司 一种增量式角度编码器光栅零位参考点编码方法及掩膜板
CN206258120U (zh) * 2016-11-23 2017-06-16 广州市精谷智能科技有限公司 利用增量式角度编码器光栅零位参考点编码方法编制的掩膜板
CN106767962A (zh) * 2016-12-16 2017-05-31 凌子龙 差分式光电编码器及位置判断方法
CN206300667U (zh) * 2016-12-20 2017-07-04 常州市新瑞得仪器有限公司 编码盘、应用该编码盘的光电测角编码器
CN106989763A (zh) * 2017-03-31 2017-07-28 中国科学院长春光学精密机械与物理研究所 一种图像式光电编码器的绝对式光栅码盘
CN109073424B (zh) * 2017-12-12 2020-10-23 深圳市大疆创新科技有限公司 旋转参数检测方法、编码器、激光雷达和无人机
US10921718B2 (en) * 2017-12-15 2021-02-16 Nikon Corporation Two-dimensional position encoder

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000346676A (ja) * 1999-06-04 2000-12-15 Canon Inc 光学式ロータリーエンコーダ
CN2771823Y (zh) * 2005-02-05 2006-04-12 苏州一光仪器有限公司 绝对式角度编码器
CN101153808A (zh) * 2007-09-19 2008-04-02 苏州一光仪器有限公司 单码道绝对式角度编码度盘及采用该度盘的编码器

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114895422A (zh) * 2022-03-30 2022-08-12 中国船舶重工集团公司第七0七研究所 一种片式圆光栅的安装调整结构及安装调整方法
CN114895422B (zh) * 2022-03-30 2024-04-23 中国船舶重工集团公司第七0七研究所 一种片式圆光栅的安装调整结构及安装调整方法

Also Published As

Publication number Publication date
US20200378804A1 (en) 2020-12-03
CN111279158A (zh) 2020-06-12
JP2021524015A (ja) 2021-09-09
DE112019004545T5 (de) 2021-05-20

Similar Documents

Publication Publication Date Title
WO2020215205A1 (zh) 一种光栅盘及反馈***
US10557707B2 (en) Encoder, driving device, and robot apparatus
JP5527637B2 (ja) エンコーダ、光学モジュール及びサーボシステム
JP5538870B2 (ja) ロータリーエンコーダ
JP5574899B2 (ja) ロータリーエンコーダ及びこれを備えた光学機器
KR20130106315A (ko) 인코더
JP6263965B2 (ja) エンコーダ、エンコーダ付きモータ、サーボシステム
US20160178407A1 (en) Encoder and motor with encoder
US20160164383A1 (en) Encoder and motor with encoder
JPWO2014141370A1 (ja) エンコーダ、エンコーダ付きモータ、サーボシステム
US11644346B2 (en) Rotation angle encoder apparatus
US9035232B2 (en) Method for working out the eccentricity and the angular position of a rotating element and device for carrying out such a method
JP2015090306A (ja) エンコーダ、エンコーダ付きモータ、サーボシステム
JP2015090300A (ja) エンコーダ、エンコーダ付きモータ、サーボシステム
WO2015152242A1 (ja) 反射型エンコーダ
CN113541406B (zh) 一种高精度振镜电机反馈***及其设计方法
US20150123587A1 (en) Encoder, motor with encoder, and servo system
WO2016092638A1 (ja) エンコーダ及びエンコーダ付きモータ
JP2016109633A (ja) エンコーダ及びエンコーダ付きモータ
JP5999583B2 (ja) エンコーダ、エンコーダ付きモータ、サーボシステム
WO2016092639A1 (ja) エンコーダ及びエンコーダ付きモータ
JP2002257595A (ja) 回転変位量を検出する装置及び方法、補正装置及び方法、並びに、ディスク
CN214407370U (zh) 一种基于时间测角的新型传感器
CN216695041U (zh) 用于旋转编码器的可降低安装精度要求的码盘结构
CN113847867B (zh) 一种用于旋转机构的零位传感器

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2020535089

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19926364

Country of ref document: EP

Kind code of ref document: A1

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 15.03.2022)

122 Ep: pct application non-entry in european phase

Ref document number: 19926364

Country of ref document: EP

Kind code of ref document: A1