A method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer

Abstract

This invention discloses a method for assembling and adjusting a dual-readhead photoelectric encoder on a gyro accelerometer. The method includes the following steps: initial assembly of the code disk base and pointer assembly; dimensional measurement; grating gap adjustment; reassembly of the pointer assembly; code disk assembly installation; signal testing; tightening the pointer assembly and code disk assembly; receiver board installation; and wiring harness tidying. An oscilloscope is used to observe the sine and cosine signals and the zero position. An industrial control computer reads the angle values ​​given by the signal processing and output circuit to determine the installation accuracy of the dual-readhead photoelectric encoder, achieving the goal of high-precision installation of the dual-readhead photoelectric encoder on the gyro accelerometer. This invention solves the problem of high-precision installation of dual-readhead photoelectric encoders within the limited space of a gyro accelerometer. The assembly and adjustment operation is simpler and more efficient. In particular, it eliminates the need for high-precision optical methods such as multi-faceted prisms and autocollimators, making it more suitable for offline installation, adjustment, or maintenance in user field settings.

Description

Technical Field

[0001] This invention belongs to the field of inertial technology and the field of photoelectric encoder application research, and in particular relates to a method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyroscope accelerometer. Background Technology

[0002] The pendulum integrating gyro accelerometer (Gyro accelerometer for short), mounted on a stable platform in inertial space, is used to measure the apparent acceleration of a vehicle. It remains the most accurate accelerometer for engineering applications worldwide and is an irreplaceable core inertial instrument in inertial navigation systems. Since the performance and accuracy of the gyro accelerometer directly affect the navigation positioning accuracy of the vehicle, ensuring the accuracy of gyro accelerometer measurements is of paramount importance for achieving high-precision navigation.

[0003] Based on the working principle of gyro accelerometers, it is known that the rotational speed of the outer ring of a gyro accelerometer is linearly proportional to the apparent acceleration. The outer ring can be considered as a general shaft system. An angle sensor is used to measure the rotational angle (angular position) of the shaft system. The rotational speed is obtained by dividing the angle rotated in a certain time by the time. Angle sensors include photoelectric, inductive, capacitive, resolver, and variable reluctance types, each with its own advantages and disadvantages. Generally, gyro accelerometers use a variable reluctance sensor as the angle sensor. It outputs sine and cosine signals when the gyro accelerometer precesses, and outputs a system reference excitation signal. The sine and cosine signals are converted into pulses with positive and negative polarities and counted. The number of pulses per unit time represents the magnitude of the apparent acceleration. Currently, photoelectric encoders have overcome technical challenges such as the long-term stability of the light source and the relatively weak structural strength. They maintain good performance in harsh environments and have been widely used in applications requiring long-term stable operation and high-precision measurement. The patent "A Gyroscope Accelerometer Output System Based on Photoelectric Encoder" (application number CN202411385818) proposes a new technical solution for replacing the variable magnetoresistive sensor with a photoelectric encoder in the outer ring output device of a gyroscope accelerometer. This breaks through the output accuracy limitations of the original variable magnetoresistive sensor and improves the accuracy of the pendulum gyroscope accelerometer. The accuracy of photoelectric encoders is affected by factors such as installation errors, engraving errors, and electronic subdivision errors. In particular, the first-order error caused by installation eccentricity accounts for the largest proportion. The technical solution using a single reading head is difficult to compensate for these errors, resulting in limited accuracy capability of a single reading head photoelectric encoder. To improve the outer ring angle measurement accuracy of gyroscope accelerometers based on photoelectric encoders, a gyroscope accelerometer outer ring angle measurement scheme based on dual reading head photoelectric encoders has been proposed. In principle, dual reading heads can compensate for installation errors, making the outer ring angle measurement of the gyroscope accelerometer higher than that of a single reading head photoelectric encoder scheme. However, in reality, high-precision installation is a prerequisite for the high accuracy of dual reading heads, and also a necessary and sufficient condition for ensuring higher accuracy of the gyroscope accelerometer outer ring angle measurement device. Summary of the Invention

[0004] The purpose of this invention is to overcome the inapplicability of the single-readhead photoelectric encoder assembly and adjustment method, and to provide an assembly and adjustment method for a dual-readhead photoelectric encoder on a gyro accelerometer. This method allows for precise assembly and adjustment of the dual-readhead photoelectric encoder onto the gyro accelerometer at room temperature, realizing the advantage of equal distribution and average installation error of the dual readheads. The measurement error of the dual readheads is smaller than that of a single readhead, improving the outer ring angle measurement accuracy of the gyro accelerometer. Furthermore, this assembly and adjustment method is simpler and more efficient.

[0005] The objective of this invention is achieved through the following technical solutions:

[0006] A method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer includes:

[0007] (1) Initially install the code disk base onto the outer ring axis of the gyroscope accelerometer, and initially radially and symmetrically fix the light-pointing components of the two reading heads onto the housing of the gyroscope accelerometer; each reading head includes a light-pointing component, the two reading heads share a receiving plate, and the light-pointing component includes a light-pointing base, a light-emitting plate, and a static grating.

[0008] (2) Use a dial indicator to test the distance from the mounting surface of the code disk base to the mounting surface of the two reading head light-pointing bases, and the distance from the static grating surface of the two reading head light-pointing components to their respective light-pointing base mounting surfaces.

[0009] (3) Based on the dimensional information measured in step (2), place a light-pointing base pad between the light-pointing base of the first reading head and the housing of the gyroscope accelerometer, and between the light-pointing base of the second reading head and the housing of the gyroscope accelerometer, so that the gap between the code disk and the static grating of the first reading head, and the gap between the code disk and the static grating of the second reading head meet the requirements.

[0010] (4) Wipe the surface of the static grating of the two reading head light-pointing components and observe under a microscope to ensure that there are no foreign objects or scratches on the surface of the static grating. After the inspection is completed, fix the light-pointing components of the two reading heads radially and symmetrically to the gyroscope accelerometer housing with screws. At this time, it is not necessary to tighten the screws.

[0011] (5) Wipe the code disk and code disk base, and glue the code disk and code disk base coaxially. After the glue cures, the code disk assembly is formed. Wipe the code disk on the code disk assembly to keep the code disk clean. Then install the code disk assembly to the outer ring shaft system of the gyroscope accelerometer and make it in close contact with the stepped surface of the outer ring shaft system of the gyroscope accelerometer. Use the nut to press the code disk assembly to the stepped surface of the outer ring shaft system of the gyroscope accelerometer. Check the flatness of the code disk surface. When the flatness meets the installation requirements, fix the nut.

[0012] (6) Test the signal of the dual-reader photoelectric encoder with an oscilloscope to see if it meets the requirements. If it does, proceed to step (7).

[0013] (7) Tighten the screws of the two reading head light components, clean up the excess material, and seal them with epoxy glue; apply glue to the threads between the nut and the outer ring shaft of the gyroscope accelerometer; seal the screws of the receiving board with silicone rubber GD414, and let it stand for the glue to cure.

[0014] (8) Fix the receiving plate of the reading head to the housing of the gyroscope accelerometer;

[0015] (9) The receiving board and the light-pointing component are connected by a wire harness. The wire harness is tidied up to complete the installation of the dual-reading photoelectric encoder on the gyroscope accelerometer.

[0016] Preferably, in step (1), the encoder base is in close contact with the stepped surface of the outer ring axis of the gyroscope accelerometer; the light-pointing components of the two reading heads are initially in close contact with the reference surface of the gyroscope accelerometer housing.

[0017] Preferably, in step (3), the gap between the code disk and the static grating of the first reading head is δ1 = L1 - L2, and the gap between the code disk and the static grating of the first reading head is δ2 = L1 - L3;

[0018] Where L1 is the dimension from the mounting surface of the code disk base to the mounting surface of the light-pointing base of the first reading head, L2 is the dimension from the surface of the static grating of the light-pointing component of the first reading head to the mounting surface of the light-pointing base of the second reading head, and L3 is the dimension from the surface of the static grating of the light-pointing component of the second reading head to the mounting surface of the light-pointing base.

[0019] Preferably, the shape of the light-pointing base pad is consistent with the mounting surface of the light-pointing base.

[0020] Preferably, in steps (4) and (5), a lint-free cloth soaked in petroleum ether or acetone is used for wiping.

[0021] Preferably, in step (5), the method for calculating the surface flatness of the code disk is as follows:

[0022] Place the dial indicator pointer on the code disk surface, select multiple points around the circumference of the code disk, gently slide the dial indicator to each point, and record the reading; determine the flatness based on the range of multiple sets of readings.

[0023] Preferably, in step (5), if the flatness does not meet the requirements, the code disk assembly will be reworked.

[0024] Preferably, in step (6), the signal of the dual-reader photoelectric encoder is tested using an oscilloscope to determine whether it meets the requirements. The method is as follows:

[0025] The first oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the second oscilloscope monitors the sinusoidal signal sin2 of the second reading head via channel II; the second oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the second oscilloscope monitors the cosine signal cos2 of the second reading head via channel II; the third oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the third oscilloscope monitors the zero-position signal of the first reading head via channel II; the fourth oscilloscope monitors the sinusoidal signal sin2 of the second reading head via channel I, and the fourth oscilloscope monitors the zero-position signal of the second reading head via channel II.

[0026] Set the first and second oscilloscopes to XY mode, and the third and fourth oscilloscopes to normal mode.

[0027] Rotate the outer ring axis of the gyro accelerometer and, based on the changes in the Lissajous plots on the first and second oscilloscopes, slightly adjust the two light-pointing components until the sine and cosine phases meet the phase relationship requirements; if the phase difference between the two signals is 180°, the waveform will be a diagonal line spanning the 2nd and 4th quadrants.

[0028] Rotate the outer ring axis of the gyro accelerometer, and slightly adjust the two light-pointing components according to the sine signal and zero-position signal on the third and fourth oscilloscopes until the zero-position signal on the third and fourth oscilloscopes is completely in phase with the sine signal.

[0029] Rotate the outer ring axis of the gyro accelerometer and repeatedly check the first, second, third and fourth oscilloscopes. After confirming that all meet the requirements, finally determine the installation position of the light-pointing component.

[0030] Connect the zero-position adjustment position on the receiver board to the resistor box. Adjust the resistor box to change the zero-position signal output voltage so that its secondary peak value is lower than the TQ1 value. Record the resistance value of the resistor box at this time and disconnect the resistor box.

[0031] Based on the determined resistance value, solder the chip resistor to the zero-position adjustment position of the receiving board;

[0032] The signal processing and output circuit is connected to the industrial control computer via an RS485 to USB serial port adapter cable; the signal processing and output circuit is used to process the signal from the dual-reader photoelectric encoder to obtain the outer ring angle of the gyro accelerometer.

[0033] On the industrial control computer, open the serial port assistant, set the baud rate, parity, and data bits, and then rotate the outer ring axis of the gyro accelerometer at a constant speed. Read the outer ring angle of the gyro accelerometer at a 1kHz update frequency. When the outer ring angle is continuous and uniform for 360°, it is determined that the signal of the dual-reader photoelectric encoder meets the requirements.

[0034] Preferably, in step (8), the method for fixing the receiving plate to the gyroscope accelerometer housing is as follows:

[0035] Place four insulating pads on the housing of the gyroscope accelerometer;

[0036] After inspecting the surface of the receiving plate under a microscope and confirming that there are no appearance or quality problems, the receiving plate is placed on four insulating pads.

[0037] The receiving board is provided with four mounting holes, each corresponding to an insulating pad. Screws are passed through the mounting holes and insulating pads in sequence and screwed into the receiving board fixing threaded holes on the gyroscope accelerometer housing.

[0038] Use a multimeter to check the insulation resistance between the input / output interface of the receiver board and the housing of the gyroscope accelerometer. If the insulation resistance meets the requirements, it is installed correctly; if it does not meet the requirements, troubleshoot the problem.

[0039] Preferably, the wire harness arrangement process is as follows: the wire harness is fitted with a heat shrink tubing, the wires exit through the outlet of the gyroscope accelerometer housing, and the wire harness is pressed tightly.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] This invention is the first to propose a method for mounting and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer. By determining the appropriate height of the pointer base pad or code disk base through a dimensional chain, it solves the problem of measuring and adjusting the gap between the moving and stationary gratings of the photoelectric encoder, and realizes the axial high-precision installation of the dual-reading-head photoelectric encoder within the limited space of the gyro accelerometer.

[0042] This invention employs multiple oscilloscopes to simultaneously monitor the sine and cosine signals and zero-position signal of a dual-readhead photoelectric encoder, and uses serial port data to monitor the outer ring angle measurement under uniform motion. This solves the problem that traditional assembly and adjustment methods based on multi-faceted prisms and autocollimators cannot be used, and enables high-precision installation of a dual-readhead photoelectric encoder within the limited space of a gyro accelerometer with only one open side.

[0043] The dual-reading head photoelectric encoder assembly and adjustment method of the present invention uses the most commonly used tools and methods, making the operation simpler and more efficient. The process is simple and clear, making it easier to guide production personnel to operate independently. It does not require high-precision optical methods such as multi-faceted prisms and autocollimators, making it more suitable for offline scenarios such as user sites for assembly, adjustment, or replacement and maintenance. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of a gyroscope accelerometer based on a dual-reading-head photoelectric encoder according to an embodiment of the present invention;

[0045] Figure 2This is a schematic diagram of the assembly and adjustment steps of a dual-reading-head photoelectric encoder on a gyroscope accelerometer in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of dimension measurement in an embodiment of the present invention;

[0047] Figure 4 This is a phase diagram of the sine and cosine signals in an embodiment of the present invention. Detailed Implementation

[0048] like Figure 1 As shown, the dual-readhead photoelectric encoder 1 includes two readheads (readhead #1 and readhead #2) and a code disk assembly; each readhead includes a light-pointing component; the code disk assembly includes a code disk 4 and a code disk base 6; the light-pointing component of readhead #1 includes a light-emitting plate 14, a light-pointing base 15, and a static grating 3; the light-pointing component of readhead #2 includes a light-emitting plate 12, a light-pointing base 11, and a static grating 7; the two readheads use the same receiving plate 2, and their respective receiving optical devices are diametrically distributed on the receiving plate 2.

[0049] The light-emitting plate is mounted on the light-indicating base. Three infrared solid-state light-emitting diodes (SLEDs) corresponding to the sine, cosine, and zero-position signals are set on the light-emitting plate. The infrared SLEDs emit light under the power supply and provide the light source. The light-indicating base is the mounting reference for the light-emitting plate and the static grating. Under the condition that the light-emitting plate provides the light source, the static grating forms moiré fringes with the code disk. The receiving plate has two photoelectric receiving elements of the reading heads distributed radially symmetrically. They work under the power supply and the light source to form the differential sine signal, differential cosine signal, and zero-position signal of the two reading heads.

[0050] The dual-readhead photoelectric encoder 1 is connected to the signal processing and output circuit 9 outside the gyroscope accelerometer via wiring harness 8. The oscilloscope 18 and industrial computer 22 are both connected to the signal processing and output circuit 9. The signal processing and output circuit processes the signals from the dual-readhead photoelectric encoder to obtain the outer ring angle of the gyroscope accelerometer. The code disk base 6 is locked onto the outer ring shaft system 13 of the gyroscope accelerometer using nut 5. The pointer base 11 and pointer base 14 are fixed to the gyroscope accelerometer housing 10 via the pointer base fixing threaded hole 16. The receiver plate 2 is fixed to the gyroscope accelerometer housing 10 via the receiver plate fixing threaded hole 17.

[0051] This invention discloses a method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer, the specific steps of which are as follows:

[0052] Initial assembly of the encoder base and light pointer assembly: The encoder base is installed to the outer ring axis of the gyro accelerometer, making close contact with the stepped surface of the outer ring axis; the light pointer assemblies of reading heads #1 and #2 are installed to the gyro accelerometer housing, making close contact with the reference surface of the gyro accelerometer housing. The light pointer assembly includes a light pointer base, a light-emitting plate, and a static grating.

[0053] Dimensional Measurement: Use a dial indicator to measure the dimension L1 from the mounting surface of the code disk base (i.e., the contact surface between the code disk base and the code disk) to the mounting surface of the pointer base (i.e., the contact surface between the pointer base and the gyro accelerometer housing, which is also the reference surface of the gyro accelerometer housing); use a dial indicator to measure the dimension L2 from the surface of the static grating of the pointer assembly of the #1 reading head to the mounting surface of the pointer base; use a dial indicator to measure the dimension L3 from the surface of the static grating of the pointer assembly of the #2 reading head to the mounting surface of the pointer base.

[0054] Grating gap adjustment: The gap value δ1 between the code disk and the static grating of the #1 reading head is obtained by calculating L1-L2; the gap value δ2 between the code disk and the static grating of the #2 reading head is obtained by calculating L1-L3; according to the gap requirements between the code disk and the static grating, a suitable shim is selected and placed between the light-pointing base and the gyro accelerometer housing to raise the light-pointing assembly, so as to ensure that the grating gap values ​​δ1 and δ2 are within the required range.

[0055] Reinstallation of the light indexing components: Wipe the surface of the static grating of the light indexing components of the two reading heads with a lint-free cloth dampened with petroleum ether or acetone. After checking that there are no foreign objects in the light indexing components, use four screws to fasten the two light indexing components to the gyro accelerometer housing. The two light indexing components are installed diametrically opposite each other.

[0056] Code disk assembly installation: Wipe the code disk and code disk base with a lint-free cloth dampened with petroleum ether or acetone. Coaxially glue the code disk and code disk base together. After the glue cures, the code disk assembly is formed. Wipe the code disk on the code disk assembly with a lint-free cloth dampened with petroleum ether or acetone to keep the code disk clean. Then install the code disk assembly to the outer ring shaft system of the gyroscope accelerometer, ensuring close contact with the stepped surface of the outer ring shaft system. Use nuts to press the code disk assembly tightly to the stepped surface of the outer ring shaft system of the gyroscope accelerometer.

[0057] Test signal: Loosen the screws of the light-pointing assembly; use an oscilloscope connected to the signal processing and output circuit to monitor the sine and cosine signals and zero-position signal of the two reading heads; rotate the outer ring axis of the gyro accelerometer; and adjust the light-pointing assembly slightly according to the changes in the Lissajous plot on the oscilloscope until the sine and cosine phases meet the phase relationship requirements and the zero-position signal of each reading head is completely in phase with the sine signal, thus determining the installation position of the light-pointing assembly.

[0058] Secure the light pointer assembly and encoder assembly: Tighten the screws of the light pointer assembly, remove any excess material, and apply adhesive; apply adhesive between the nut of the encoder assembly and the outer ring shaft of the gyroscope accelerometer; seal the screws of the receiver board with silicone rubber.

[0059] Receiver board installation: Place the four insulating pads of the receiver board onto the gyroscope accelerometer housing. Place the receiver board on the four insulating pads and use four screws to pass through the four mounting holes and the four insulating pads of the receiver board, and screw them into the gyroscope accelerometer housing to fix the receiver board to the gyroscope accelerometer housing. Use a multimeter to check the insulation resistance between the input / output interface of the receiver board and the gyroscope accelerometer housing. The insulation resistance should be greater than 200MΩ.

[0060] Organize the wiring harness: Cover the wiring harness with heat shrink tubing, exit through the outlet, and tighten the wiring harness to complete the installation of the dual-reading photoelectric encoder on the gyroscope accelerometer.

[0061] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0062] Example:

[0063] In this invention, the back of the static grating 3 is uniformly coated with adhesive and fixed to the pre-reserved installation position on the light-pointing base 15 by bonding. After inspecting the surface of the light-emitting plate under a microscope to ensure that the light-emitting plate has no appearance or quality problems, the light-emitting plate 14 is installed on the pre-reserved installation position on the light-pointing base 15 and fixed with two screws.

[0064] Apply adhesive evenly to the back of the static grating 7 and fix it to the reserved installation position on the light-pointing base 11 by bonding. Check the surface of the light-emitting plate under a microscope for defects. After ensuring that the light-emitting plate has no appearance or quality problems, install the light-emitting plate 12 to the reserved installation position on the light-pointing base 11 and fix it with two screws.

[0065] like Figure 2 As shown, the specific steps of the method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to the present invention are as follows:

[0066] (1) Initial installation of encoder base and light pointer assembly: The encoder base 6 is installed to the outer ring shaft system 13 of the gyroscope accelerometer and is in close contact with the stepped surface of the outer ring shaft system 13 of the gyroscope accelerometer; the light pointer assembly of the 1# reading head and the light pointer assembly of the 2# reading head are installed to the gyroscope accelerometer housing 10 and are in close contact with the reference surface of the gyroscope accelerometer housing 10.

[0067] (2) Dimensional Measurement: Use a dial indicator to measure the dimension L1 from the mounting surface of the code disk base (i.e., the contact surface between the code disk base 6 and the code disk 4) to the mounting surface of the pointer base 11 (i.e., the contact surface between the pointer base 11 and the gyroscope accelerometer housing 10, which is also the reference surface of the gyroscope accelerometer housing 10); use a dial indicator to measure the dimension L2 from the surface of the static grating 3 of the pointer assembly of the #1 reading head to the mounting surface of the pointer base 15; use a dial indicator to measure the dimension L3 from the surface of the static grating 7 of the pointer assembly of the #2 reading head to the mounting surface of the pointer base 11. Figure 3 As shown.

[0068] (3) Grating gap adjustment: The gap value δ1 between the code disk 4 and the static grating 3 of the #1 reading head is obtained by calculating L1-L2; the gap value δ2 between the code disk 4 and the static grating 7 of the #2 reading head is obtained by calculating L1-L3; according to the gap requirements of 0.09mm≤δ1≤0.11mm and 0.09mm≤δ2≤0.11mm between the code disk and the static grating, a suitable pointer base shim is selected and placed between the pointer base 11, the pointer base 15 and the gyro accelerometer housing 10 to raise the two pointer components and ensure that the grating gap values ​​δ1 and δ2 meet the requirements. Among them, the pointer base shim is a pre-processed thin sheet with a thickness of 0.001mm to 0.01mm, and its shape is consistent with the mounting surface of the pointer base.

[0069] (4) Reinstallation of the light-pointing components: Wipe the surfaces of the static grating 3 and static grating 7 with a lint-free cloth dipped in petroleum ether or acetone. Observe under a microscope to ensure that there are no foreign objects or scratches on the surfaces of the static grating 3 and static grating 7. After checking that there are no foreign objects in the light-pointing components, use 4 screws M2.5 to tighten the 2 light-pointing components to the light-pointing base fixing thread hole 16 on the gyroscope accelerometer housing 10. The two light-pointing components are installed symmetrically. At this time, it is not necessary to tighten the screws.

[0070] (5) Code disk assembly installation: Wipe the code disk 4 and code disk base 6 with a lint-free cloth dipped in petroleum ether or acetone. Coaxially glue the code disk 4 and code disk base 6 together. After the glue has cured, the code disk assembly is formed. Wipe the code disk 4 on the code disk assembly with a lint-free cloth dipped in petroleum ether or acetone to keep the code disk 4 clean. Then install the code disk assembly onto the outer ring shaft system 13 of the gyroscope accelerometer, ensuring close contact with the stepped surface of the outer ring shaft system 13 of the gyroscope accelerometer. Use the nut 5 to press the code disk assembly tightly onto the stepped surface of the outer ring shaft system 13 of the gyroscope accelerometer. Place the dial indicator pointer on the surface of the code disk 4 and gently slide the dial indicator to record the reading. Select multiple points around the circumference of the code disk 4 and repeat this step. Calculate the flatness based on the range of multiple sets of measurement data and determine whether the flatness meets the installation requirements (flatness less than 0.003mm). Finally, fix the nut. If the flatness does not meet the requirements, the code disk assembly should be reworked and finely ground.

[0071] (6) Test signal: Loosen the screws of the light-pointing assembly; connect the receiver board 2 to the light-pointing assembly via wires, and connect the receiver board to the signal processing and output circuit 9 via wire harness 8; connect the signal processing and output circuit 9 using an oscilloscope; monitor the sine signal sin1 of reading head #1 using channel I of oscilloscope 18, and monitor the sine signal sin2 of reading head #2 using channel II of oscilloscope 18; monitor the sine signal sin1 of reading head #1 using channel I of oscilloscope 19, and monitor the cosine signal cos2 of reading head #2 using channel II of oscilloscope 19; monitor the sine signal sin1 of reading head #1 using channel I of oscilloscope 20, and monitor the zero-position signal of reading head #1 using channel II of oscilloscope 20. Channel I of oscilloscope 21 monitors the sinusoidal signal sin2 from reading head #2, and channel II of oscilloscope 21 monitors the zero-position signal from reading head #2. Oscilloscopes 18 and 19 are set to XY mode, while oscilloscopes 20 and 21 operate in normal mode. The outer ring axis 13 of the gyro accelerometer is rotated. Based on the changes in the Lissajous plot on oscilloscopes 18 and 19, the two light-pointing components are slightly adjusted until the sine and cosine phases meet the phase relationship requirements (according to the Lissajous plot principle, if the phase difference between the two signals is 0, the waveform is a diagonal line spanning quadrants 1 and 3 (0°±10°); if the phase difference between the two signals is 90°, the waveform is a standard circle (90°±10°), see...). Figure 4If the phase difference between the two signals is 180°, the waveform will be a diagonal line spanning quadrants 2 and 4 (180°±10°). Rotate the outer ring axis 13 of the gyro accelerometer and, based on the sine wave signal and zero-position signal on oscilloscopes 20 and 21, slightly adjust the two light-pointing components until the zero-position signal on oscilloscopes 20 and 21 is completely in phase with the sine wave signal. Rotate the outer ring axis 13 of the gyro accelerometer and repeatedly confirm the positions of oscilloscopes 18, 19, 20, and 21. After confirming that all meet the requirements, finally determine the installation position of the light-pointing components. Connect the zero-position adjustment position on receiver board 2 to the resistor box. Adjust the resistor box to change the zero-position signal output voltage so that its secondary peak value is lower than TQ1 (the through-loop signal of the first reading head). Record the resistance value of the resistor box at this time. Disconnect the resistor box and solder the surface mount resistor to the zero-position adjustment position on the receiver board according to the determined resistance value. Connect the signal processing and output circuit 9 to the industrial control computer 22 through the RS485 to USB serial port adapter cable. Open the serial port assistant on the industrial control computer, set the baud rate, parity, and data bits, and rotate the outer ring axis 13 of the gyroscope accelerometer at a constant speed. Read the outer ring angle of the gyroscope accelerometer with a 1kHz update frequency to determine that the outer ring angle is continuous and uniform 360° around the entire circle.

[0072] (7) Secure the light-pointing assembly and the encoder assembly: Tighten the screws of the light-pointing assembly, clean up any excess material, and seal it with epoxy glue; apply glue to the threads between the nut 5 and the outer ring shaft 14 of the gyroscope accelerometer; seal the screws of the receiver plate 2 with silicone rubber GD414 and let it stand for the glue to cure.

[0073] (8) Receiver board installation: Place the four insulating pads of the receiver board onto the gyroscope accelerometer housing 10; inspect the surface of the receiver board 2 under a microscope for defects to ensure that the receiver board 2 has no appearance or quality problems; place the receiver board on the four insulating pads, and use four screws to pass through the four mounting holes and the four insulating pads of the receiver board 2 respectively, and screw them into the receiver board fixing thread holes 17 on the gyroscope accelerometer housing 10 to fix the receiver board 2 to the gyroscope accelerometer housing 10; use a multimeter to check the insulation resistance between the input / output interface of the receiver board 2 and the gyroscope accelerometer housing 10, requiring an insulation resistance greater than 200MΩ. If the insulation resistance meets the requirements, the installation is in place; if the requirements are not met, troubleshooting should be carried out, focusing on whether the solder wires of the receiver board are in contact with the gyroscope accelerometer housing, and whether the printed lines of the receiver board are exposed copper, causing contact with the screws, etc.

[0074] (9) Organize the wiring harness: The wiring harness is covered with heat shrink tubing, and the wires are exited through the outlet of the gyroscope accelerometer housing 10. The wiring harness is then pressed to complete the installation of the dual-reading photoelectric encoder on the gyroscope accelerometer.

[0075] This invention discloses a method for assembling and adjusting a dual-readhead photoelectric encoder on a gyro accelerometer. The method includes the following steps: initial assembly of the code disk base and pointer assembly; dimensional measurement; grating gap adjustment; reassembly of the pointer assembly; installation of the code disk assembly; signal testing; tightening the pointer assembly and code disk assembly; receiver board installation; and wiring harness tidying. An oscilloscope is used to observe the sine and cosine signals and the zero position. An industrial control computer reads the angle values ​​given by the signal processing and output circuit to determine the installation accuracy of the dual-readhead photoelectric encoder. This achieves radially symmetrical installation of the dual readheads on the gyro accelerometer housing, with the code disk assembly installed on the outer ring axis of the gyro accelerometer, achieving the goal of high-precision installation of the dual-readhead photoelectric encoder on the gyro accelerometer. This invention solves the problem of high-precision installation of dual-readhead photoelectric encoders within the limited space of a gyro accelerometer. The assembly and adjustment operation is simpler and more efficient, especially since it eliminates the need for high-precision optical methods such as multi-faceted prisms and autocollimators, making it more suitable for offline scenarios such as user sites for assembly, adjustment, or maintenance.

[0076] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer, characterized in that, include: (1) Initially install the code disk base onto the outer ring axis of the gyroscope accelerometer, and initially fix the light-pointing components of the two reading heads radially and symmetrically onto the housing of the gyroscope accelerometer; each reading head includes a light-pointing component, and the two reading heads share a receiving plate. The light-pointing component includes a light-pointing base, a light-emitting plate, and a static grating. (2) Use a dial indicator to test the distance from the mounting surface of the code disk base to the mounting surface of the two reading head light-pointing bases, and the distance from the static grating surface of the two reading head light-pointing components to their respective light-pointing base mounting surfaces. (3) Based on the dimensional information measured in step (2), place a light-pointing base pad between the light-pointing base of the first reading head and the housing of the gyroscope accelerometer, and between the light-pointing base of the second reading head and the housing of the gyroscope accelerometer, so that the gap between the code disk and the static grating of the first reading head, and the gap between the code disk and the static grating of the second reading head meet the requirements. (4) Wipe the surface of the static grating of the two reading head light-pointing components and observe under a microscope to ensure that there are no foreign objects or scratches on the surface of the static grating. After the inspection is completed, fix the light-pointing components of the two reading heads radially and symmetrically to the gyroscope accelerometer housing with screws. At this time, it is not necessary to tighten the screws. (5) Wipe the code disk and code disk base, and glue the code disk and code disk base coaxially. After the glue cures, the code disk assembly is formed. Wipe the code disk on the code disk assembly to keep the code disk clean. Then install the code disk assembly to the outer ring shaft system of the gyroscope accelerometer and make it in close contact with the stepped surface of the outer ring shaft system of the gyroscope accelerometer. Use the nut to press the code disk assembly to the stepped surface of the outer ring shaft system of the gyroscope accelerometer. Check the flatness of the code disk surface. When the flatness meets the installation requirements, fix the nut. (6) Test the signal of the dual-reader photoelectric encoder with an oscilloscope to see if it meets the requirements. If it does, proceed to step (7). (7) Tighten the screws of the two reading head light components, clean up the excess material, and seal them with epoxy glue; apply glue to the threads between the nut and the outer ring shaft of the gyroscope accelerometer; seal the screws of the receiving board with silicone rubber GD414, and let it stand for the glue to cure. (8) Fix the receiving plate of the reading head to the housing of the gyroscope accelerometer; (9) The receiving board and the light-pointing component are connected by a wire harness. The wire harness is tidied up to complete the installation of the dual-reading photoelectric encoder on the gyroscope accelerometer.

2. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (1), the encoder base is in close contact with the stepped surface of the outer ring axis of the gyroscope accelerometer; the light-pointing components of the two reading heads are initially in close contact with the reference surface of the gyroscope accelerometer housing.

3. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (3), the gap between the code disk and the static grating of the first reading head is δ1 = L1 - L2, and the gap between the code disk and the static grating of the first reading head is δ2 = L1 - L3; Where L1 is the dimension from the mounting surface of the code disk base to the mounting surface of the light-pointing base of the first reading head, L2 is the dimension from the surface of the static grating of the light-pointing component of the first reading head to the mounting surface of the light-pointing base of the second reading head, and L3 is the dimension from the surface of the static grating of the light-pointing component of the second reading head to the mounting surface of the light-pointing base.

4. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: The shape of the light-pointing base pad is consistent with the mounting surface of the light-pointing base.

5. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In steps (4) and (5), a lint-free cloth soaked in petroleum ether or acetone is used for wiping.

6. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (5), the method for calculating the surface flatness of the code disk is as follows: Place the dial indicator pointer on the code disk surface, select multiple points around the code disk, gently slide the dial indicator to each point, and record the reading; calculate the flatness based on the range of multiple sets of readings.

7. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (5), if the flatness does not meet the requirements, the code disk assembly will be reworked.

8. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (6), the signal of the dual-reader photoelectric encoder is tested using an oscilloscope to determine if it meets the requirements. The method is as follows: The first oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the second oscilloscope monitors the sinusoidal signal sin2 of the second reading head via channel II; the second oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the second oscilloscope monitors the cosine signal cos2 of the second reading head via channel II; the third oscilloscope monitors the sinusoidal signal sin1 of the first reading head via channel I, and the third oscilloscope monitors the zero-position signal of the first reading head via channel II; the fourth oscilloscope monitors the sinusoidal signal sin2 of the second reading head via channel I, and the fourth oscilloscope monitors the zero-position signal of the second reading head via channel II. Set the first and second oscilloscopes to XY mode, and the third and fourth oscilloscopes to normal mode. Rotate the outer ring axis of the gyro accelerometer and, based on the changes in the Lissajous plots on the first and second oscilloscopes, slightly adjust the two light-pointing components until the sine and cosine phases meet the phase relationship requirements; if the phase difference between the two signals is 180°, the waveform will be a diagonal line spanning the 2nd and 4th quadrants. Rotate the outer ring axis of the gyro accelerometer, and slightly adjust the two light-pointing components according to the sine signal and zero-position signal on the third and fourth oscilloscopes until the zero-position signal on the third and fourth oscilloscopes is completely in phase with the sine signal. Rotate the outer ring axis of the gyro accelerometer and repeatedly check the first, second, third and fourth oscilloscopes. After confirming that all meet the requirements, finally determine the installation position of the light-pointing component. Connect the zero-position adjustment position on the receiver board to the resistor box. Adjust the resistor box to change the zero-position signal output voltage so that its secondary peak value is lower than the TQ1 value. Record the resistance value of the resistor box at this time and disconnect the resistor box. Based on the determined resistance value, solder the chip resistor to the zero-position adjustment position of the receiving board; The signal processing and output circuit is connected to the industrial control computer via an RS485 to USB serial port adapter cable; the signal processing and output circuit is used to process the signal from the dual-reader photoelectric encoder to obtain the outer ring angle of the gyro accelerometer. On the industrial control computer, open the serial port assistant, set the baud rate, parity, and data bits, and then rotate the outer ring axis of the gyro accelerometer at a constant speed. Read the outer ring angle of the gyro accelerometer at a 1kHz update frequency. When the outer ring angle is continuous and uniform for 360°, it is determined that the signal of the dual-reader photoelectric encoder meets the requirements.

9. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: In step (8), the method for fixing the receiving plate to the gyroscope accelerometer housing is as follows: Place four insulating pads on the housing of the gyroscope accelerometer; After inspecting the surface of the receiving plate under a microscope and confirming that there are no appearance or quality problems, the receiving plate is placed on four insulating pads. The receiving board is provided with four mounting holes, each corresponding to an insulating pad. Screws are passed through the mounting holes and insulating pads in sequence and screwed into the receiving board fixing threaded holes on the gyroscope accelerometer housing. Use a multimeter to check the insulation resistance between the input / output interface of the receiver board and the housing of the gyroscope accelerometer. If the insulation resistance meets the requirements, it is installed correctly; if it does not meet the requirements, troubleshoot the problem.

10. The method for assembling and adjusting a dual-reading-head photoelectric encoder on a gyro accelerometer according to claim 1, characterized in that: The wiring harness arrangement process is as follows: the wiring harness is fitted with heat shrink tubing, the wires exit through the outlet of the gyroscope accelerometer housing, and the wiring harness is then pressed tightly.

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