Method for manufacturing high-precision angular displacement sensor

Abstract

The application discloses a kind of high-precision angular displacement sensor manufacturing method, comprising the following steps: assemble each component together;Linearly trim, or skip this step;Zero adjustment, first install shell and rotating shaft with adjusting tool, and then install the relevant components of angular displacement sensor, then apply m volt voltage at power input, measure acquisition voltage, and rotate insulating sleeve until the voltage collected is in the range of m / 2±m / n volt, complete zero adjustment and tighten insulating sleeve;The angular displacement sensor assembly without installing cover plate after completing zero adjustment is placed in the oven as a whole, and the glue between each component is dried and solidified;Remove adjusting tool;Install cover plate, complete the manufacture of high-precision angular displacement sensor.The application realizes high-precision adjustment of angular displacement sensor before leaving factory through high-precision zero adjustment method, significantly improves the detection accuracy of angular displacement sensor, and is especially suitable for angular displacement detection field with high detection accuracy requirement.

Description

Technical Field

[0001] This invention relates to a method for manufacturing an angular displacement sensor, and more particularly to a method for manufacturing a high-precision angular displacement sensor. Background Technology

[0002] An angular displacement sensor (potentiometer) is an important angular position feedback component, mainly used for measuring the angular displacement of equipment such as servo motors, providing feedback on the absolute position of rotating parts such as the shaft of a servo motor. With the development of technology, angular displacement sensors are widely used in industrial, shipbuilding, aviation, and aerospace fields where high precision, long lifespan, and various stringent testing requirements are demanded.

[0003] The basic structure of an angular displacement sensor includes a housing, a rotating shaft, a resistive element (conductive plastic resistive element), a brush, a current collector ring, and an insulating sleeve. The rotating shaft passes through a corresponding through hole in the housing and is connected via a bearing. The resistive element is installed inside the housing, and the rotating shaft passes through the central through hole of the resistive element. The insulating sleeve is fitted onto the rotating shaft, the current collector ring is mounted on the insulating sleeve, and the brush is mounted on the current collector ring and contacts the resistance band of the resistive element. During operation, an external device drives the rotating shaft to rotate, which in turn drives the insulating sleeve, current collector ring, and brush to rotate synchronously. The brush slides against the resistance band of the resistive element, generating a changing electrical signal. An external processor calculates the rotation angle information of the rotating shaft based on the change in the electrical signal, thus realizing the angular displacement detection function.

[0004] With the widespread application of angular displacement sensors in various precision equipment, the requirements for their detection accuracy are becoming increasingly stringent. Besides the crucial factors of the resistivity band itself (such as the uniformity and resistivity consistency of the conductive plastic layer) and the reliability of the contact between the brush and the resistivity band, the accuracy of the zero-adjustment position of the angular displacement sensor is also a very important influencing factor. Specifically, it's crucial to ensure that the brush is precisely in the center of the resistivity band when the sensor is at zero. Inaccuracy in this area will inevitably affect the detection accuracy. To further illustrate this point, the following diagram is provided:

[0005] like Figure 1 As shown, the first resistive element 1 of the sensor is provided with an arc-shaped resistance strip 6. The two ends of the resistance strip 6 are respectively provided with a first power supply positive input terminal 2 and a first power supply negative input terminal 7. The positive and negative terminals of the external power supply are connected to the first power supply positive input terminal 2 and the first power supply negative input terminal 7 respectively through the lead wire 8. Figure 1 The diagram also shows a conductive strip 3 disposed on the first resistor 1, with a signal output terminal 4 located in the middle of the conductive strip 3. The conductive strip 3 is not a necessary structure. Figure 1 Used in Figure 2The electric signal collected by the first brush 11 in the first resistor body 1 is transmitted to the first signal output end 4 through the second brush 9, which is a common electric signal transmission structure; in addition, the center through hole 5 of the first resistor body 1 is used for the rotating shaft to pass through.

[0006] In combination with Figure 1 and Figure 2 , when applied, the first brush 11 and the second brush 9 are respectively installed on the first current collecting ring 10 and are in mutual conduction, the first brush 11 is in contact with the resistance band 6, and the second brush 9 is in contact with the conductive band 3; the theoretical zero position of the sensor is that the first brush 11 is located at the middle position of the resistance band 6, and correspondingly, the second brush 9 is located at the middle position of the conductive band 3, as shown in Figure 3 . However, in actual application, it is difficult to realize high-precision zero adjustment, that is, generally, the first brush 11 deviates from the middle position of the resistance band 6, as shown in Figure 2 . In the production process, the conventional zero adjustment method mainly relies on the feeling and experience of the workers, so it is difficult to eliminate the deviation, and after the sensor is packaged, it is more difficult to adjust the zero position.

[0007] In addition, the dual-redundancy angle displacement sensor is also an angle displacement sensor that is often used, and the use of two circuit components (one circuit component includes a resistor body, an insulating sleeve, a current collecting ring and one or two brushes) can improve the detection precision, or the dual-redundancy angle displacement sensor can still work normally when one circuit component fails. For the dual-redundancy angle displacement sensor, in addition to the problem of insufficient zero adjustment precision, there is also a problem of low synchronization precision between the two circuit components, which will also lead to a decrease in the detection precision of the entire sensor, making it difficult for the angle displacement sensor to be applied to application scenarios with extremely high detection precision requirements.

[0008] In addition, the resistance band of the resistor body of the conventional angle displacement sensor lacks a high-precision testing method in the process of trimming, which leads to insufficient trimming precision. SUMMARY

[0009] The purpose of the present application is to provide a manufacturing method of a high-precision angle displacement sensor with high-precision zero position to solve the above problems.

[0010] The present application realizes the above-mentioned purpose through the following technical solutions:

[0011] A manufacturing method of a high-precision angular displacement sensor, the high-precision angular displacement sensor comprising a shell, a cover plate, a rotating shaft and a first circuit assembly, the first circuit assembly comprising a first resistor, a first insulating sleeve, a first current collector and a first brush, the rotating shaft passing through a corresponding through hole on the shell and being connected by a bearing, the first resistor being installed in the shell, the rotating shaft passing through a central through hole of the first resistor, the first insulating sleeve being sleeved on the rotating shaft, the first current collector being installed on the first insulating sleeve, the first brush being installed on the first current collector and being in contact with a resistance band of the first resistor, two ends of the resistance band of the first resistor being respectively provided with a first positive electrode input end and a first negative electrode input end, the cover plate being connected with an open end of the shell, the manufacturing method of the high-precision angular displacement sensor comprising the following steps:

[0012] Step 1, assembling all components of the high-precision angular displacement sensor together except the cover plate, and not curing between the first insulating sleeve and the rotating shaft;

[0013] Step 2, if linear trimming of the first resistor is needed, performing linear trimming, otherwise skipping this step;

[0014] Step 3, zero adjustment, comprising the following steps:

[0015] Step 3.1, installing the shell with an adjusting tool, and making the rotating shaft be in vertical and the open end of the shell be above, at the same time, making the shell and the rotating shaft both unable to rotate by the adjusting tool;

[0016] Step 3.2, rotating the first insulating sleeve, so that the first brush is approximately in the middle position of the resistance band of the first resistor;

[0017] Step 3.3, applying m-volt voltage between the first positive electrode input end and the first negative electrode input end, and setting the central angle between the first positive electrode input end and the first negative electrode input end as n degrees, then the voltage corresponding to each degree is m / n degrees, and the voltage corresponding to the middle position of the resistance band of the first resistor is m / 2 volts;

[0018] Step 3.4, measuring the voltage of the electrical signal collected by the first brush, if the voltage is within the range of m / 2±m / n volts, then the first insulating sleeve is pressed tightly from top to bottom by the adjusting tool, the zero adjustment is completed and the process goes to step 4, otherwise, the process goes to step 3.5;

[0019] Step 3.5, if the voltage of the electrical signal collected by the first brush is greater than m / 2+m / n volts, rotate the first insulating sleeve towards the first power supply negative input end, and drive the first brush to rotate on the resistance band of the first resistance body towards the first power supply negative input end; if the voltage of the electrical signal collected by the first brush is less than m / 2-m / n volts, rotate the first insulating sleeve towards the first power supply positive input end, and drive the first brush to rotate on the resistance band of the first resistance body towards the first power supply positive input end; during the rotation of the first insulating sleeve, continuously measure the voltage of the electrical signal collected by the first brush, until the voltage is within the range of m / 2±m / n volts, then stop rotating the first insulating sleeve, and press the first insulating sleeve tightly from top to bottom by the adjusting tool to complete zero adjustment;

[0020] Step 4, place the angle displacement sensor assembly without the cover plate and after zero adjustment into an oven, and dry and solidify the glue liquid between the components;

[0021] Step 5, after taking out the angle displacement sensor assembly after solidification, remove the adjusting tool;

[0022] Step 6, install the cover plate to complete the production of the high-precision angle displacement sensor.

[0023] As a preferred, in order to facilitate the transmission of the electrical signal collected by the first brush to the external processor through the lead on the first resistance body, the first current collecting ring is further provided with a second brush, the second brush is in contact with the conductive band on the first resistance body, and the middle part of the conductive band is provided with a first signal output end.

[0024] As a preferred, in order to improve the synchronization accuracy of the two circuit assemblies of the dual-redundancy angle displacement sensor to improve the detection accuracy of the whole sensor, the high-precision angle displacement sensor further comprises a middle shell and a second circuit assembly, the second circuit assembly comprises a second resistance body, a second insulating sleeve, a second current collecting ring and a third brush, the middle shell is connected between the shell and the cover plate, the second resistance body is installed in the middle shell, the rotating shaft passes through the center through hole of the second resistance body, the second insulating sleeve is sleeved on the rotating shaft, the second current collecting ring is installed on the second insulating sleeve, the third brush is installed on the second current collecting ring and in contact with the resistance band of the second resistance body, the two ends of the resistance band of the second resistance body are respectively provided with a second power supply positive input end and a second power supply negative input end, the central angle between the second power supply positive input end and the second power supply negative input end is the same as the central angle between the first power supply positive input end and the first power supply negative input end; the steps 3 and 4 further comprise the following steps:

[0025] Step 4.1, connect the middle housing with the outer housing, install the second resistor in the second circuit assembly into the middle housing, install the second insulating sleeve outside the rotating shaft, the second insulating sleeve is installed with the second current collector ring, the second current collector ring is installed with the third brush, the third brush is in contact with the resistance band of the second resistor, the second insulating sleeve is not fixed with the rotating shaft;

[0026] Step 4.2, if linear trimming is needed for the second resistor, linear trimming is performed, otherwise this step is skipped;

[0027] Step 4.3, synchronous adjustment, including the following steps:

[0028] Step 4.3.1, rotate the second insulating sleeve so that the third brush is approximately in the middle position of the resistance band of the second resistor;

[0029] Step 4.3.2, adjust the adjustment tool, use the adjustment tool to make the outer housing unable to rotate but the rotating shaft can rotate freely;

[0030] Step 4.3.3, apply m-volt voltage between the first positive input terminal and the first negative input terminal, and between the second positive input terminal and the second negative input terminal, respectively connect the corresponding signal output terminals of the first brush and the third brush with the digital multimeter, and test the voltage difference of the two output signals;

[0031] Step 4.3.4, press the second insulating sleeve from top to bottom through the adjustment tool, rotate the rotating shaft so that the first brush slides between the two ends of the working band of the first resistor and the third brush slides between the two ends of the working band of the second resistor at least once, continuously test the voltage difference between the two output signals and find the maximum voltage difference, if the maximum voltage difference is within m / 2±m / n volts, use the adjustment tool to make the rotating shaft return to zero position and unable to rotate, complete synchronous adjustment, otherwise go to the next step;

[0032] Step 4.3.5, if the maximum voltage difference is greater than m / 2+m / n volts or less than m / 2-m / n volts, the pressure of the second insulating sleeve by the adjusting tool is released, and the rotating shaft is made unable to rotate by the adjusting tool, then the voltage corresponding to the first brush and the voltage corresponding to the third brush are compared, if the voltage corresponding to the first brush is greater than the voltage corresponding to the third brush, the second insulating sleeve is rotated towards the second positive input end of the power supply, if the voltage corresponding to the third brush is greater than the voltage corresponding to the first brush, the second insulating sleeve is rotated towards the second negative input end of the power supply, the rotation angle is proportional to the size of the maximum voltage difference, after the rotation is completed, the rotating shaft is made able to freely rotate by the adjusting tool;

[0033] Step 4.3.6, steps 4.3.4-4.3.5 are repeated until the maximum voltage difference between the two output signals measured is within m / 2±m / n volts, then the second insulating sleeve is pressed tightly from top to bottom by the adjusting tool, and the rotating shaft is made unable to rotate by the adjusting tool after returning to zero position, and the synchronous adjustment is completed.

[0034] As a preferred, in order to facilitate the transmission of the third brush collected electrical signal to the external processor through the lead on the second resistance body, the fourth brush is installed on the second current collecting ring, the fourth brush is in contact with the conductive strip on the second resistance body, and the middle part of the conductive strip is provided with a second signal output end.

[0035] As a preferred, in order to improve the linear trimming precision of the resistance body, linear trimming is included in steps 2 and 4.2, the actual resistance value of each position on the resistance strip of the corresponding resistance body is trimmed to the error between the theoretical resistance value by laser trimming within ±0.05%, The test formula is as follows:

[0036]

[0037] Wherein, Un ´ is the actual measured output voltage value of each test position, Un is the voltage value specified by the theoretical output characteristic at the position, n is the serial number of the test position, Un ´ -Un ) max is the maximum voltage difference between the actual measured voltage and the theoretical voltage, Un ´ -Un ) min is the minimum voltage difference between the actual measured voltage and the theoretical voltage, U 0Is the input voltage value of the positive electrode input end of the resistance band corresponding to the resistance body.

[0038] The beneficial effects of the present application are:

[0039] The present application realizes the high-precision zero adjustment purpose by corresponding the middle position of the resistance band of the first resistance body with the corresponding theoretical voltage, comparing the output signal voltage collected by the first brush with the theoretical voltage, and continuously adjusting the position of the first brush on the resistance band of the first resistance body until the difference between the output signal voltage collected by the first brush and the theoretical voltage is not greater than m / n volts, that is, the error between the actual zero and the theoretical zero is not greater than 1° (central angle angle), realizes the high-precision zero adjustment purpose; By comparing the output voltage collected by the first brush of the first circuit component and the third brush of the second circuit component, comparing the maximum voltage difference with m / n volts, and adjusting the position of the third brush on the resistance band of the second resistance body until the maximum voltage difference is not greater than m / n volts, that is, the actual synchronization error between the first circuit component and the second circuit component is not greater than 1° (central angle angle), thereby realizing the high-precision synchronization adjustment purpose of the dual-redundancy angular displacement sensor; By using a specific test formula as the linear modification basis of the resistance band on the resistance body, the high-precision modification purpose of the resistance band is realized; The present application finally realizes the high-precision adjustment of the angular displacement sensor before leaving the factory through the high-precision zero adjustment, high-precision synchronization adjustment and high-precision modification method, significantly improves the detection precision of the angular displacement sensor, and does not need to be adjusted during use, is convenient to use, and is especially suitable for the angular displacement detection field with high detection precision requirement. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 Is the top view structural schematic diagram of the first resistance body of the angular displacement sensor, and the structure of the second resistance body in the dual-redundancy angular displacement sensor is the same as that;

[0041] Figure 2 Is the top view structural schematic diagram of the first resistance body, the first current collecting ring, the first brush and the second brush of the angular displacement sensor when the high-precision zero adjustment is not realized;

[0042] Figure 3 Is the top view structural schematic diagram of the first resistance body, the first current collecting ring, the first brush and the second brush of the angular displacement sensor after realizing the high-precision zero adjustment, and the structure of the second resistance body, the second current collecting ring, the second brush and the second brush in the dual-redundancy angular displacement sensor is the same as that;

[0043] Figure 4 Is the bottom view structural schematic diagram of the adjusting tool base used in the manufacturing method of the high-precision angular displacement sensor;

[0044] Figure 5This is a top view of the pressure sleeve of the adjustment fixture used in the manufacturing method of the high-precision angular displacement sensor described in this invention.

[0045] Figure 6 This is a top view (AA) of the pressure sleeve of the adjustment tooling used in the manufacturing method of the high-precision angular displacement sensor described in this invention.

[0046] Figure 7 This is a schematic diagram of the main cross-sectional structure of the sleeve of the adjustment tooling used in the manufacturing method of the high-precision angular displacement sensor described in this invention.

[0047] Figure 8 This is a schematic diagram of the main view of the angular displacement sensor and the adjustment fixture during zero-position adjustment in the manufacturing method of the high-precision angular displacement sensor described in this invention.

[0048] Figure 9 This is a schematic diagram of the main cross-sectional structure of the angular displacement sensor and the adjustment fixture during synchronous adjustment in the manufacturing method of the high-precision angular displacement sensor described in this invention.

[0049] Figure 10 This is a schematic diagram of the front cross-sectional structure of the high-precision angular displacement sensor described in this invention after it has been manufactured. Detailed Implementation

[0050] The present invention will be further described below with reference to the accompanying drawings:

[0051] The following section will specifically describe the structure of the adjustment fixture used in the manufacturing method of the high-precision angular displacement sensor described in this invention, such as... Figures 4-7 As shown, the adjustment fixture used in the manufacturing method of the high-precision angular displacement sensor of the present invention includes a base 12, a pressure sleeve 19, and a sleeve 23. The base 12 is provided with a housing for mounting the high-precision angular displacement sensor (see...). Figures 8-10 The outer shell 27) and the base cavity 13 with an opening at the top, the cavity wall of the base cavity 13 is provided with a plurality of transverse outer shell positioning holes 17 along the circumferential direction, and a plurality of positioning screws ( Figure 4 Not shown in the image, see [link / reference]. Figure 8 and Figure 9 The positioning screws 26 pass through multiple housing positioning holes 17. A central through hole is located at the bottom center of the base cavity 13, and a positioning post 15 is installed within this central through hole. A rotating shaft for the high-precision angular displacement sensor (see...) is located at the center of the positioning post 15. Figures 8-10 The flat section at the lower end of the pivot 28 (see Figures 8-10The flat section 32 of the lower end of the shaft of the high-precision angular displacement sensor is positioned through the vertical shaft positioning hole 16, the radial section of the shaft positioning hole 16 is the same as the radial section of the flat section of the lower end of the shaft of the high-precision angular displacement sensor, the pressing sleeve 19 is provided with a central through hole 22 for the shaft of the high-precision angular displacement sensor to pass through vertically, the upper middle part of the pressing sleeve 19 is provided with a pressing sleeve notch 21 with an upper end opening and forms two pressing sleeve walls 20 with elasticity distributed on the opposite sides, and the sleeve 23 is sleeved outside the pressing sleeve 19 through the vertical central through hole 25 of the sleeve 23, the lateral screw holes 24 are provided on the opposite side walls of the sleeve 23, and the two fastening screws (not shown in the figure, see Figure 7 not shown in the figure, see Figure 8 and Figure 9 The fastening screws 30 pass through the two screw holes 24 respectively. As shown in Figures 4-8 and Figure 9 Preferably, the lower part of the central through hole of the bottom of the base inner cavity 13 is provided with a base groove (not labeled in the figure), the lower part of the positioning column 15 is outwardly protruded to form an annular mounting part (not labeled in the figure), the annular mounting part is arranged in the base groove, and the annular mounting part is connected with the base 12 through a plurality of vertical screws (not labeled in the figure); as shown in Figure 4 The upper part of the cavity wall of the base inner cavity 13 is provided with a wire passing groove 14 for the lead wire (see the lead wire 8 of Figure 1 ) of the high-precision angular displacement sensor to pass through; the lower end of the pressing sleeve 19 is provided with a pressing sleeve protruding ring 18 outwardly protruded.

[0052] The high-precision dual-redundancy angular displacement sensor is taken as an example to specifically illustrate the application:

[0053] Combined with Figures 1-10The high-precision angular displacement sensor comprises a shell 27, a middle shell 34, a cover plate 40, a rotating shaft 28, a first circuit assembly and a second circuit assembly, the first circuit assembly comprises a first resistor body 1, a first insulating sleeve 29, a first current collector ring 10, a first brush 11 and a second brush 9, the second circuit assembly comprises a second resistor body 35, a second insulating sleeve 38, a second current collector ring 37, a third brush 39 and a fourth brush 36, the rotating shaft 28 passes through the corresponding through hole on the shell 27 and is connected through a bearing 31, the first resistor body 1 is installed in the shell 27, the rotating shaft 28 passes through the center through hole of the first resistor body 1 and the center through hole of the second resistor body 35, the first insulating sleeve 29 and the second insulating sleeve 38 are sequentially sleeved on the rotating shaft 28, the first current collector ring 10 is installed on the first insulating sleeve 29, the first brush 11 is installed on the first current collector ring 10 and is in contact with the resistance band 6 of the first resistor body 1, the second brush 9 is installed on the first current collector ring 10 and is in contact with the conductive band 3 on the first resistor body 1, the middle part of the conductive band 3 is provided with a first signal output end 4, the two ends of the resistance band 6 of the first resistor body 1 are respectively provided with a first positive electrode input end 2 and a first negative electrode input end 7, the second resistor body 35 is installed in the middle shell 34, the second insulating sleeve 38 is sleeved on the rotating shaft 28, the second current collector ring 37 is installed on the second insulating sleeve 38, the third brush 39 is installed on the second current collector ring 37 and is in contact with the resistance band (not shown in the figure, refer to the resistance band 6) of the second resistor body 35, the fourth brush 36 is installed on the second current collector ring 37 and is in contact with the conductive band (not shown in the figure, refer to the conductive band 3) of the second resistor body 35, the middle part of the conductive band is provided with a second signal output end (not shown in the figure, refer to the first signal output end 4), the two ends of the resistance band of the second resistor body 35 are respectively provided with a second positive electrode input end and a second negative electrode input end (not shown in the figure, refer to the first positive electrode input end 2 and the first negative electrode input end 7), the central angle angle between the second positive electrode input end and the second negative electrode input end is the same as the central angle angle between the first positive electrode input end 2 and the first negative electrode input end 7, one end of the middle shell 34 is connected with the open end of the shell 27, the cover plate 40 is connected with the other end of the middle shell 34, and the two opposite outer walls of the middle shell 34 are provided with hand holding parts 33. Figures 1-3 Figures 1-3 Figures 1-3 Figures 1-3

[0054] Figures 1-10 The manufacturing method of the high-precision angular displacement sensor comprises the following steps:

[0055] Step 1, assemble all the components of the high-precision angular displacement sensor except the cover plate 40, the middle shell 34 and the second circuit assembly together, and do not solidify between the first insulating sleeve 29 and the rotating shaft 28. ​​​​​

[0056] Step 2, linear trimming: trimming the actual resistance value of each position (the total number of positions is according to actual needs) on the resistance band 6 of the first resistor body 1 to the error between the actual resistance value and the theoretical resistance value through laser trimming Within ±0.05%, Calculated by the following test formula:

[0057]

[0058] Wherein, Un ´ is the actual measured output voltage value of each test position, Un is the voltage value specified by the theoretical output characteristic at this position, n is the serial number of the test position, ( Un ´ -Un ) max is the maximum voltage difference value of the actual measured voltage deviating from the theoretical voltage, ( Un ´ -Un ) min is the minimum voltage difference value of the actual measured voltage deviating from the theoretical voltage, U 0 is the input voltage value of the first power supply positive input end 2 of the resistance band 6 of the first resistor body 1;

[0059] Step 3, zero adjustment, including the following steps:

[0060] Step 3.1, install the shell 27 in the base inner cavity 13 of the base 12 of the adjustment tool, pass the plurality of (four in the figure) positioning screws 26 through the plurality of (four in the figure) shell positioning holes 17 respectively and connect with the corresponding screw holes on the shell 27 (the shell positioning holes 17 can also be designed as screw holes, and the inner end of the positioning screw 26 is abutted against the outer wall of the shell 27), so that the shell 27 cannot rotate, and the rotating shaft 28 is in the vertical direction and the open end of the shell 27 is located above, at the same time, pass the flat section 32 of the rotating shaft 28 through the rotating shaft positioning hole 16 of the positioning column 15, so that the rotating shaft 28 cannot rotate; at the same time, install the pressing sleeve 19 on the upper end of the rotating shaft 28 and make the pressing sleeve convex ring 18 located above the first insulating sleeve 29, install the sleeve 23 outside the pressing sleeve wall 20 of the pressing sleeve 19, and pass the two locking screws 30 through the two screw holes 24 respectively but not locked;

[0061] Step 3.2, rotate the first insulating sleeve 29, so that the first brush 11 is approximately (i.e. according to the feeling and experience of the staff) at the middle position of the resistance band 6 of the first resistor body 1;

[0062] Step 3.3, apply m volts voltage between the first power supply positive input end 2 and the first power supply negative input end 7, set the central angle between the first power supply positive input end 2 and the first power supply negative input end 7 as n degrees, then each degree corresponds to m / n volts, the middle position of the resistance band 6 of the first resistor body 1 corresponds to m / 2 volts; for example, apply 10 volts voltage, the central angle is 100 degrees, then each degree corresponds to 0.1 volts, the middle position of the resistance band 6 of the first resistor body 1 corresponds to 5 volts;

[0063] Step 3.4, measure the voltage of the electrical signal collected by the first brush 11 through the first signal output end 4, if the voltage is in the range of m / 2±m / n volts, then press the pressure sleeve 19 from top to bottom to tightly press the first insulating sleeve 29 and lock the two clamping screws 30, the two clamping screws 30 press the two elastic pressure sleeve walls 20 on the outer wall of the rotating shaft 28, realize the position fixation between the first insulating sleeve 29 and the rotating shaft 28, realize the position fixation of the first brush 11 on the resistance band 6 of the first resistor body 1, complete the zero adjustment and turn to step 4, otherwise turn to step 3.5;

[0064] Step 3.5, if the voltage of the electrical signal collected by the first brush 11 is greater than m / 2+m / n volts, then rotate the first insulating sleeve 29 towards the first power supply negative input end 7, drive the first brush 11 to rotate on the resistance band 6 of the first resistor body 1 towards the first power supply negative input end 7; if the voltage of the electrical signal collected by the first brush 11 is less than m / 2-m / n volts, then rotate the first insulating sleeve 29 towards the first power supply positive input end 2, drive the first brush 11 to rotate on the resistance band 6 of the first resistor body 1 towards the first power supply positive input end 2; during the process of rotating the first insulating sleeve 29, continuously measure the voltage of the electrical signal collected by the first brush 11, until the voltage is in the range of m / 2±m / n volts, then stop rotating the first insulating sleeve 29, and press the first insulating sleeve 29 from top to bottom by the method of step 3.4 to complete the zero adjustment;

[0065] Step 4.1, connect the middle shell 34 with the shell 27, install the second resistor body 35 in the second circuit assembly in the middle shell 34, remove the pressure sleeve 19 and the sleeve 23, install the second insulating sleeve 38 in the second circuit assembly outside the rotating shaft 28, install the second current collector ring 37 on the second insulating sleeve 38, install the third brush 39 and the fourth brush 36 on the second current collector ring 37, the third brush 39 contacts with the resistance band of the second resistor body 35, the fourth brush 36 contacts with the conductive band on the second resistor body 35, the second insulating sleeve 38 and the rotating shaft 28 are not fixed, then install the pressure sleeve 19 and the sleeve 23 by the method of step 3.1;

[0066] Step 4.2, linear trimming: trimming the actual resistance value of each position (the total number of positions is determined according to actual needs) on the resistance band of the second resistor 35 to the error between the actual resistance value and the theoretical resistance value by laser trimming within ±0.05%, The test formula is as follows:

[0067]

[0068] wherein, Un V is the actual measured output voltage value of each test position, Un V is the voltage value specified by the theoretical output characteristic at this position, n n is the serial number of the test position, Un V -Un ) max V is the maximum voltage difference between the actual measured voltage and the theoretical voltage, Un V -Un ) min V is the minimum voltage difference between the actual measured voltage and the theoretical voltage, U 0 V is the input voltage value of the second power supply positive input end of the resistance band of the second resistor 35;

[0069] Step 4.3, synchronous adjustment, including the following steps:

[0070] Step 4.3.1, rotate the second insulating sleeve 38 so that the third brush 39 is approximately at the middle position of the resistance band of the second resistor 35;

[0071] Step 4.3.2, remove the positioning column 15 from the base 12 so that the rotating shaft 28 can rotate freely;

[0072] Step 4.3.3, simultaneously apply a voltage of m volts between the first power supply positive input end 2 and the first power supply negative input end 7, and between the second power supply positive input end and the second power supply negative input end, and connect the corresponding signal output ends of the first brush 11 and the third brush 39 to the corresponding digital multimeter, respectively, to test the voltage difference between the two output signals;

[0073] Step 4.3.4, use the method of step 3.4 to press the second insulating sleeve 38 tightly from top to bottom, rotate the rotating shaft 28 so that the first brush 11 slides between the two ends of the working band 6 of the first resistor 1 and the third brush 39 slides between the two ends of the working band of the second resistor 35 at least once, continuously test the voltage difference between the two output signals and find the maximum voltage difference, if the maximum voltage difference is within m / 2±m / n volts, then reinstall the positioning column 15 on the base 12 so that the rotating shaft 28 cannot rotate, complete the synchronous adjustment, otherwise go to the next step;

[0074] Step 4.3.5, if the maximum voltage difference is greater than m / 2+m / n volts or less than m / 2-m / n volts, loosen the two setscrews 30, release the pressure of the pressure sleeve 19 on the second insulating sleeve 38, and reinstall the positioning column 15 on the base 12 so that the rotating shaft 28 cannot rotate (or the rotating shaft 28 can also be held by hand to temporarily not rotate when rotating the second insulating sleeve 38), then compare the voltage corresponding to the first brush 11 and the voltage corresponding to the third brush 39, if the voltage corresponding to the first brush 11 is greater than the voltage corresponding to the third brush 39, rotate the second insulating sleeve 38 towards the positive input end of the second power supply, if the voltage corresponding to the third brush 39 is greater than the voltage corresponding to the first brush 11, rotate the second insulating sleeve 38 towards the negative input end of the second power supply, the rotation angle is proportional to the size of the maximum voltage difference, and after completing the rotation, remove the positioning column 15 from the base 12 so that the rotating shaft 28 can rotate freely;

[0075] Step 4.3.6, repeat steps 4.3.4-4.3.5 until the maximum voltage difference between the two output signals is within m / 2±m / n volts, then use the method of step 3.4 to press the second insulating sleeve 38 from top to bottom, and reinstall the positioning column 15 on the base 12 after the rotating shaft 28 returns to zero position so that the rotating shaft 28 cannot rotate, complete the synchronous adjustment;

[0076] Step 4, place the completed zero position adjustment angle displacement sensor assembly without installing the cover plate 40 in an oven (not shown in the figure, a conventional method) to dry and cure the glue between the components;

[0077] Step 5, after taking out the completed curing angle displacement sensor assembly, remove the adjusting tool;

[0078] Step 6, install the cover plate 40 on the middle shell 34 to complete the production of the high-precision angle displacement sensor.

[0079] The above embodiments are only preferred embodiments of the present application and are not a limitation on the technical solutions of the present application. Any technical solutions that can be realized on the basis of the above embodiments without creative labor shall be considered to fall within the protection scope of the present application.

Claims

1. A method for manufacturing a high-precision angular displacement sensor, the high-precision angular displacement sensor comprising a housing, a cover plate, a rotating shaft and a first circuit assembly, the first circuit assembly comprising a first resistor body, a first insulating sleeve, a first current collector ring and a first brush, the rotating shaft passing through a corresponding through hole on the housing and being connected by a bearing, the first resistor body being installed in the housing, the rotating shaft passing through a central through hole of the first resistor body, the first insulating sleeve being sleeved on the rotating shaft, the first current collector ring being installed on the first insulating sleeve, the first brush being installed on the first current collector ring and being in contact with a resistor band of the first resistor body, both ends of the resistor band of the first resistor body being respectively provided with a first positive electrode input end and a first negative electrode input end, the cover plate being connected with an open end of the housing, characterized in that: The manufacturing method of the high-precision angular displacement sensor comprises the following steps: Step 1, assemble all components of the high-precision angular displacement sensor together except the cover plate, and do not solidify between the first insulating sleeve and the rotating shaft; Step 2, if linear modification is needed for the first resistor, perform linear modification, otherwise, skip this step; Step 3, zero adjustment, comprising the following steps: Step 3.1, install the shell with the adjusting tool, and make the rotating shaft in vertical position and the open end of the shell upward, at the same time, make the shell and the rotating shaft unable to rotate by the adjusting tool; Step 3.2, rotate the first insulating sleeve, and make the first brush approximately in the middle position of the resistance band of the first resistor; Step 3.3, apply m-volt voltage between the first positive input terminal and the first negative input terminal, and set the central angle between the first positive input terminal and the first negative input terminal as n degrees, then the voltage corresponding to each degree is m / n degrees, and the voltage corresponding to the middle position of the resistance band of the first resistor is m / 2 volts; Step 3.4, measure the voltage of the electric signal collected by the first brush, if the voltage is within the range of m / 2±m / n volts, then press the first insulating sleeve from top to bottom by the adjusting tool, complete zero adjustment and go to step 4, otherwise, go to step 3.5; Step 3.5, if the voltage of the electric signal collected by the first brush is greater than m / 2+m / n volts, then rotate the first insulating sleeve towards the first negative input terminal, and drive the first brush to rotate on the resistance band of the first resistor towards the first negative input terminal; if the voltage of the electric signal collected by the first brush is less than m / 2-m / n volts, then rotate the first insulating sleeve towards the first positive input terminal, and drive the first brush to rotate on the resistance band of the first resistor towards the first positive input terminal; during the rotation of the first insulating sleeve, continuously measure the voltage of the electric signal collected by the first brush, until the voltage is within the range of m / 2±m / n volts, then stop rotating the first insulating sleeve, and press the first insulating sleeve from top to bottom by the adjusting tool, complete zero adjustment; Step 4, put the angular displacement sensor assembly without the cover plate which has completed zero adjustment into the oven, and dry and solidify the glue liquid between the components; Step 5, take out the angular displacement sensor assembly after solidification, and remove the adjusting tool; Step 6, install the cover plate, and complete the manufacturing of the high-precision angular displacement sensor.

2. The method of claim 1, wherein: The first current collecting ring is further provided with a second brush, the second brush is in contact with a conductive band on the first resistor, and a first signal output terminal is arranged at the middle part of the conductive band.

3. The method of manufacturing a high precision angular displacement sensor according to claim 1 or 2, characterized in that: The high-precision angular displacement sensor further comprises a middle shell and a second circuit assembly, the second circuit assembly comprises a second resistor, a second insulating sleeve, a second current collector ring and a third brush, the middle shell is connected between the shell and the cover plate, the second resistor is installed in the middle shell, the rotating shaft passes through the center through hole of the second resistor, the second insulating sleeve is sleeved on the rotating shaft, the second current collector ring is installed on the second insulating sleeve, the third brush is installed on the second current collector ring and contacts the resistance band of the second resistor, the resistance band of the second resistor is provided with a second positive power input end and a second negative power input end at two ends respectively, and the central angle between the second positive power input end and the second negative power input end is the same as the central angle between the first positive power input end and the first negative power input end; between the step 3 and the step 4, the following steps are further included: Step 4.1, connecting the middle shell with the shell, installing the second resistor in the second circuit assembly in the middle shell, installing the second insulating sleeve in the second circuit assembly outside the rotating shaft, installing the second current collector ring on the second insulating sleeve, installing the third brush on the second current collector ring, the third brush contacting the resistance band of the second resistor, and not curing between the second insulating sleeve and the rotating shaft; Step 4.2, if linear trimming is needed for the second resistor, linear trimming is performed, otherwise, this step is skipped; Step 4.3, synchronous adjustment, including the following steps: Step 4.3.1, rotating the second insulating sleeve so that the third brush is approximately in the middle position of the resistance band of the second resistor; Step 4.3.2, adjusting the adjusting tool, and using the adjusting tool to make the shell unable to rotate but the rotating shaft can freely rotate; Step 4.3.3, simultaneously applying m-volt voltage between the first positive power input end and the first negative power input end and between the second positive power input end and the second negative power input end, connecting the signal output ends corresponding to the first brush and the third brush with the digital multimeter respectively, and testing the voltage difference of the two output signals; Step 4.3.4, pressing the second insulating sleeve tightly from top to bottom through the adjusting tool, rotating the rotating shaft so that the first brush slides between the two ends on the working band of the first resistor and the third brush slides between the two ends on the working band of the second resistor at least once, continuously testing the voltage difference between the two output signals and finding the maximum voltage difference, if the maximum voltage difference is within m / 2±m / n volts, using the adjusting tool to make the rotating shaft return to zero position and unable to rotate, completing synchronous adjustment, otherwise, moving to the next step; Step 4.3.5, if the maximum voltage difference is greater than m / 2+m / n volts or less than m / 2-m / n volts, the pressure of the adjusting tool on the second insulating sleeve is released, the rotating shaft is disabled by the adjusting tool, then the voltage corresponding to the first brush and the voltage corresponding to the third brush are compared, if the voltage corresponding to the first brush is greater than the voltage corresponding to the third brush, the second insulating sleeve is rotated towards the positive input end of the second power supply, if the voltage corresponding to the third brush is greater than the voltage corresponding to the first brush, the second insulating sleeve is rotated towards the negative input end of the second power supply, the rotation angle is proportional to the size of the maximum voltage difference, after the rotation, the rotating shaft is enabled to rotate freely by the adjusting tool; Step 4.3.6, repeat steps 4.3.4-4.3.5 until the maximum voltage difference between the two output signals is within the range of m / 2±m / n volts, then the second insulating sleeve is pressed tightly from top to bottom by the adjusting tool, and the rotating shaft is disabled by the adjusting tool after returning to zero position, and the synchronous adjustment is completed.

4. The method of claim 3, wherein: The fourth brush is further installed on the second current collecting ring, the fourth brush is in contact with the conductive strip on the second resistor, and the middle part of the conductive strip is provided with a second signal output end.

5. The method of claim 3, wherein: The step 2 and the step 4.2 both include linear trimming, the actual resistance value of each position on the resistance band of the corresponding resistance body is trimmed to the error between the theoretical resistance value by laser trimming within ± 0.05%, Calculated by the following test formula: ； wherein, Un V is the actual measured output voltage value at each test position, Un V is the voltage value defined by the theoretical output characteristic at this position, n N is the serial number of the test position, Un V -Un ) max V is the maximum voltage difference value of the measured voltage deviating from the theoretical voltage, Un V - Un ) min V is the minimum voltage difference value of the measured voltage deviating from the theoretical voltage, U 0 V is the input voltage value of the positive input terminal of the power supply corresponding to the resistance band of the resistance body.

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