A manufacturing process method for the torque motor stator of a quartz flexible accelerometer

Abstract

The present invention discloses a manufacturing process for a quartz flexible accelerometer torquer stator. The method completes assembly through the following steps: welding and positioning torquer stator assembly II and pendulum assembly, positioning torquer stator assembly I, applying a preload force using a combination fixture, positioning ring I, conducting a power-on inspection of the welded circuit board, conducting a power-on inspection after high- and low-temperature aging and centrifugation, laser welding, and then disassembling the combination fixture for review. The present invention's preload application method offsets the repulsive force of the structural magnetic field while ensuring that the positive pressure exerted by torquer stator assemblies I and II on the pendulum assembly generates sufficient friction. Thus, when in use and subjected to acceleration, the pendulum assembly does not experience relative structural micro-displacement, thereby improving the assembly quality of the torquer stator assembly and enhancing product reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of quartz flexible accelerometer preparation technology, and relates to a manufacturing process method for a quartz flexible accelerometer torquer stator. Background Art

[0002] The quartz flexible accelerometer is used to sense the acceleration along the input axis and output a DC current signal proportional to the input acceleration. When the external acceleration α acts, the inertia moment M generated by the pendulum assembly (quartz pendulum, torquer frame and torquer coil) as the sensitive component j , inertia moment M j and feedback electromagnetic torque M β The torque difference ΔM between the two causes the pendulum assembly to produce an angular displacement of 0. Through differential capacitance detection (differential variable capacitance transformation), a capacitance difference ΔC is generated, which is converted into an electrical signal after detection and then amplified. The output current I is output through the correction compensation circuit, and the feedback electromagnetic torque M is generated through the torquer. β , this electromagnetic torque M β and the pendulum's moment of inertia M j ; Phase balance, forming a closed-loop servo circuit. When the electromagnetic torque M β and the pendulum's moment of inertia M j When the phases are balanced, the current I input to the torquer is proportional to the magnitude of the acceleration α. The output current I is proportional to the capacitance difference ΔC between the detection capacitors C1 and C2, and proportional to the voltage change rate du / dt across the capacitors, i.e.:

[0003]

[0004] Therefore, in principle, the pendulum assembly → external acceleration α → angular displacement 0 → capacitance difference ΔC are directly related factors. The capacitance difference generated by non-angular displacement produced by the pendulum assembly in other ways can all be considered as interference factors.

[0005] The main issues that need to be addressed during the combination process are:

[0006] 1) Keep the change of detection capacitance difference at zero in steady state;

[0007] 2) In dynamic state, the change of the detection capacitance difference should follow the change law of acceleration;

[0008] 3) During the combined operation, detect and eliminate the changes in the detection differential capacitance caused by the micro-displacement of the pendulum assembly in any direction. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a manufacturing process method for a quartz flexible accelerometer in a torquer stator to solve the problems existing in the prior art.

[0010] The present invention provides a method for manufacturing a stator of a quartz flexible accelerometer torquer, the method comprising the following steps:

[0011] 1) Welding of torquer stator assembly II and pendulum assembly

[0012] Pass the lead wires of each terminal on the torquer stator assembly II through the ring groove of the pendulum assembly and weld them to the corresponding welding points of the pendulum assembly according to the welding definition of the quartz flexible accelerometer;

[0013] 2) Welding and positioning of torquer stator assembly II and pendulum assembly

[0014] After welding is completed, place the torquer stator assembly II at the bottom and the pendulum assembly at the top into the positioning sleeve of the combined fixture, so that the torquer stator assembly II contacts the end face of the positioning shaft of the combined fixture;

[0015] 3) Positioning of torquer stator assembly I

[0016] 3.1) Place the torquer stator assembly I onto the pendulum assembly along the inner hole of the assembly fixture positioning sleeve;

[0017] 3.2) Install the modular fixture locating shaft, locating sleeve, clamping ring II, torquer stator assembly II, and pendulum assembly in the relative position of the modular fixture base;

[0018] 3.3) Insert the pressure head of the combined fixture into the corresponding hole of the combined fixture base, pre-sleeve the ring I on the outer circle of the pressure head, and then contact the pressure head with the torquer stator assembly I;

[0019] 4) Combined clamp applies preload

[0020] 4.1) Slowly tighten the locking nut of the assembly fixture until the torquer stator assembly I contacts the pendulum assembly. Use a willow stick to adjust the angular position of the torquer stator assembly II, pendulum assembly, and torquer stator assembly I, ensuring that the engraved line of the torquer stator assembly II, the notch of the pendulum assembly, and the engraved line of the torquer stator assembly I are aligned.

[0021] 4.2) After adjusting the angle phase position, tighten the locking nut of the combination clamp;

[0022] 5) Ring I positioning

[0023] Remove the clamping ring 2 and the positioning shaft of the combined fixture, install the ring I in place, align the notch of the ring I with the engraved direction of the torquer stator assembly, and use the clamping ring I of the combined fixture to tighten the ring I;

[0024] 6) Power on check

[0025] 6.1) Connect the torquer stator assembly terminals to the servo circuit board using process wires according to the quartz flexible accelerometer wiring diagram. Perform a power-on test. The output voltage symmetry, zero bias, and return-to-zero error performance indicators under ±1g meet the requirements (i.e., each performance indicator does not exceed the set threshold range).

[0026] 6.2) If any performance indicator exceeds the tolerance (i.e., each performance indicator does not exceed the set threshold range), the preload force of the combined fixture on the torquer stator assembly should be adjusted, or the angular position of the torquer stator assembly I, the pendulum assembly, and the torquer stator assembly I should be fine-tuned until they meet the requirements. If they still do not meet the requirements, loosen the combined fixture and reassemble;

[0027] 6.3) After the room temperature performance is qualified, the high and low temperature performance test and the performance test after the centrifugal test should meet the requirements (i.e. each performance indicator does not exceed the set threshold range);

[0028] 7) Laser welding

[0029] 7.1) Align the workbench and align the laser beam with the weld position;

[0030] 7.2) First, eight welding points are evenly distributed along the circumference of the two welds, i.e. the torquer stator assembly.

[0031] Weld 4 points evenly at the connection between Ⅰ and ring Ⅰ and 4 points evenly at the connection between torquer stator assembly Ⅱ and ring Ⅰ. After welding 4 points on one side, immediately turn the combined fixture around and clamp to weld 4 points on the other side.

[0032] 7.3) Weld two sections along the circumference, one section each at the connection between the torquer stator assembly I and ring I, and one section at the connection between the torquer stator assembly II and ring I. The areas blocked by the assembly fixture are not welded for the time being;

[0033] 7.4) Remove the modular fixture from the laser welding machine. The torquer stator assembly personnel will slightly loosen the locking nut in the modular fixture and rotate the torquer stator assembly to the phase position until the weld seam originally blocked by the modular fixture is completely exposed. Then immediately tighten the locking nut in the modular fixture.

[0034] 7.5) After the weld seam covered by the modular fixture is exposed, complete the welding of the entire circle according to the above requirements;

[0035] 7.6) After welding is completed, clean up the excess laser welding residue at the weld;

[0036] 8) Recheck the performance indicators after disassembling the combined fixture.

[0037] The torquer stator uses a top-to-top magnet configuration (see attached Figure 1 , Attachment Figure 2-3As shown in Figure 2, when the torquer stator components are combined, there will be a magnetic field repulsion force of a certain magnitude.

[0038] The pendulum assembly has a certain mass m, and the vibration acceleration α generated during transportation and turnover will generate a force F that deviates from the center position. α When this force is greater than the friction resistance F between the pendulum assembly and the torquer stator assembly I and II m , a certain micro-displacement will be generated, causing the sensor's sensitive detection differential capacitance to change, that is, the capacitance difference ΔC will change and cannot be restored after the vibration disappears, causing the output current I to change and produce a zero-position output offset.

[0039] F α =ma>F m

[0040] Friction resistance F m The size of is proportional to the pressure N between the pendulum assembly and the torquer stator assemblies I and II, that is, it is proportional to the preload force applied when the torquer stator assemblies are combined. That is, the offset of the zero position can be used to determine whether the preload force during the combination meets the design requirements.

[0041] The effects of the present invention are as follows:

[0042] (1) The present invention utilizes a modular fixture (such as the attached Figure 4 The process method of clamping the stator assemblies I and II of the torquer and applying pre-tightening force is used to offset the repulsive force of the structural magnetic field, while ensuring that the positive pressure when the torquer stator assemblies I and II clamp the pendulum assembly can generate a sufficiently large friction force. Therefore, when the pendulum assembly is subjected to acceleration in the use state, the pendulum assembly will not undergo relative structural micro-displacement, thereby improving the assembly quality of the torquer stator assembly and enhancing the reliability of the product.

[0043] Since the final use state of the torquer stator assembly is to offset the repulsive force of the structural magnetic field by the laser welding process of ring I and the torquer stator assemblies I and II, due to the particularity of the laser welding process (laser welding is a connection welding, which is to overcome the repulsive force between the torque stator assemblies I and II, and there can be no angular displacement between the torquer stator assemblies I and II and the pendulum assembly after removing the combination urgency), each time the welding process reaches half of the torquer stator assembly, the combination fixture must be loosened for a reversing operation, and then a circle of welding work is completed, resulting in half of the welding being far from overcoming the repulsive force between the two torque stator assemblies. The process of loosening the combination fixture will invisibly cause the positions of the pendulum assembly and the torque stator assembly to move slightly, thereby affecting the zero bias, linearity and other performance indicators of the quartz flexible accelerometer. Therefore, during the design of the combination fixture, the base body does not adopt a symmetrical horizontal U-shaped structure (that is, a symmetrical door frame closed structure is not adopted), so that the completion rate of one laser welding is approximately more than 70%. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a schematic diagram of the exploded structure of a quartz flexible accelerometer torquer stator assembly of the present invention;

[0045] In the figure, 101-torquer stator assembly II, 102-pendulum assembly, 103-torquer stator assembly I, 104-ring I, 105-magnetic steel;

[0046] Figure 2 This is a schematic cross-sectional view of a stator assembly of a quartz flexible accelerometer torquer of the present invention;

[0047] Figure 3 This is a schematic structural diagram of the magnetizing direction of a stator assembly of a quartz flexible accelerometer torquer of the present invention;

[0048] Figure 4 This is a schematic cross-sectional structure diagram of a quartz flexible accelerometer torquer stator assembly assembly fixture of the present invention;

[0049] In the figure, 1-locking nut, 2-rubber bushing, 3-pressing head, 4-bushing, 5-seat, 6-clamping ring 1, 7-clamping ring 2, 8-positioning sleeve, 9-positioning shaft;

[0050] Figure 5 This is a schematic top view of the structure of a clamp ring of a quartz flexible accelerometer torquer stator assembly assembly fixture of the present invention;

[0051] Figure 6 for Figure 4 Schematic diagram of the AA section structure;

[0052] Figure 7 It is a schematic diagram of the three-dimensional structure of the combined clamp of the present invention;

[0053] Figure 8 This is a schematic diagram of the assembly process of the modular fixture of the present invention;

[0054] Figure 9 This is a process flow chart for the stator assembly of a quartz flexible accelerometer torquer. DETAILED DESCRIPTION

[0055] The present invention will be further described below with reference to specific embodiments.

[0056] Example 1: Figure 1-9 As shown in the figure, a manufacturing process of a quartz flexible accelerometer torquer stator is as follows: welding and positioning of torquer stator assembly II and pendulum assembly → positioning of torquer stator assembly I → applying preload force to the assembly fixture → positioning of ring I → welding circuit board power-on inspection → power-on inspection after high and low temperature aging and centrifugation → laser welding → disassembling the assembly fixture for re-inspection (see the attached figure). Figure 9The specific steps are as follows:

[0057] Step 1: Welding the torquer stator assembly II and the pendulum assembly

[0058] 1) Use alcohol to remove the Figure 1 Clean the parts shown and let them dry at room temperature;

[0059] 2) Install the pendulum assembly on the combined fixture, tighten the positioning sleeve with the clamp ring 2, and then gently place the torquer stator assembly II along the inner hole of the positioning sleeve on the pendulum assembly, so that the two side terminals are aligned with the ring grooves on both sides of the pendulum assembly. Figure 7 As shown;

[0060] 3) Then, use the assembly fixture to flip the torquer stator assembly II onto the core shaft of the welding fixture and install the welding fixture. Thread the lead wires from each terminal of the torquer stator assembly II through the ring groove of the pendulum assembly and weld them to the corresponding solder points of the pendulum assembly according to the quartz flexible accelerometer welding specifications. Ensure that the welds are firm, the solder points are as small as possible, and each welding time does not exceed 3 seconds.

[0061] Step 2: Welding and positioning of torquer stator assembly II and pendulum assembly

[0062] After welding is completed, place the torquer stator assembly II at the bottom and the pendulum assembly at the top into the positioning sleeve of the combined fixture. The torquer stator assembly II contacts the end face of the positioning shaft of the combined fixture. Figure 6 As shown;

[0063] Step 3: Positioning the Torquer Stator Assembly I

[0064] 1) Place the torquer stator assembly I on the pendulum assembly along the inner hole of the positioning sleeve of the combined fixture;

[0065] 2) Install the combination fixture positioning shaft, positioning sleeve, clamping ring II, torquer stator assembly II, and pendulum assembly in the relative position of the combination fixture seat, as shown in the attached Figure 7 As shown;

[0066] 3) Pass the pressure head of the combined fixture through the corresponding hole of the combined fixture base, pre-sleeve the ring I on the outer circle of the pressure head, and then contact the pressure head with the torquer stator assembly I.

[0067] Step 4: Apply preload force with the combined fixture

[0068] 1) Slowly tighten the locking nut of the combined fixture until the torquer stator assembly I contacts the pendulum assembly. Use a willow stick to adjust the angular position of the torquer stator assembly II, pendulum assembly, and torquer stator assembly I (the engraved line of the torquer stator assembly II, the notch of the pendulum assembly, and the engraved line of the torquer stator assembly I are aligned);

[0069] 2) After adjusting the angular position, tighten the locking nut of the assembly clamp by about 30°;

[0070] Step 5: Loop I positioning

[0071] Remove the clamping ring 2 and the positioning shaft of the combined fixture, and press the ring Ⅰ Figure 1 Install it in place, align the notch of ring I with the engraved line of the torquer stator assembly, and use the clamp ring 1 of the combination clamp to tighten ring I;

[0072] Step 6: Power on and check

[0073] 1) According to the quartz flexible accelerometer wiring diagram, connect the terminals of the torquer stator assembly to the servo circuit board with process wires and perform a power-on test.

[0074] 2) Performance indicators such as zero bias, noise, and ±1g output voltage should meet requirements. If performance indicators are out of tolerance, adjust the preload force of the combination clamp on the torquer stator assembly, or fine-tune the angular position of the torquer stator assembly II, pendulum assembly, and torquer stator assembly I until they meet the requirements. If they still do not meet the requirements, loosen the combination clamp and reassemble.

[0075] 3) After the room temperature performance is qualified, the high and low temperature performance test and the performance test after the centrifugal test should meet the requirements. If the performance index is out of tolerance, debug according to the requirements of item 2 in step 6. After debugging is completed, re-test the high and low temperature performance and the performance test after the centrifugal test should meet the requirements.

[0076] Step 7: Laser Welding

[0077] 1) Install the torquer stator assembly together with the combined fixture on the laser welding machine;

[0078] 2) Weld ring I to torquer stator assembly I and torquer stator assembly II respectively.

[0079] Welding requirements are as follows:

[0080] a) Align the workbench and align the laser beam with the weld position;

[0081] b) First, symmetrically distribute 8 welding points along the circumference of the two welds, that is, 4 welding points are evenly distributed at the connection between the torquer stator assembly I and the ring I, and 4 welding points are evenly distributed at the connection between the torquer stator assembly II and the ring I. After welding the 4 welding points on one side, immediately turn the assembly fixture around and clamp it to weld the 4 welding points on the other side;

[0082] c) Then weld two sections along the circumference as a whole (one section each at the connection between the torquer stator assembly I and ring I, and one section at the connection between the torquer stator assembly II and ring I). The position blocked by the assembly fixture is not welded for the time being;

[0083] d) Remove the modular fixture from the laser welding machine, and have the torquer stator assembly assembler slightly loosen the locking nut in the modular fixture, rotate the torquer stator assembly to the angular phase position until the weld originally covered by the modular fixture is completely exposed, and then immediately tighten the locking nut in the modular fixture;

[0084] e) After the weld seam covered by the modular fixture is exposed, complete the welding of the entire circle according to the above requirements;

[0085] f) After welding is completed, clean the excess laser welding residue at the clean weld;

[0086] Step 8: Disassemble the fixture and check

[0087] Remove the assembly fixture and recheck according to the requirements of step 6. It should meet the requirements. If not, remove the laser weld seam and reassemble it according to the above requirements.

[0088] Embodiment 2: A combination fixture is used for clamping operation in the manufacturing process method, and the combination fixture includes a locking nut 1, a pressure head 3, a bushing 4, a seat body 5, a clamping ring 1 6, a clamping ring 2 7, a positioning sleeve 8 and a positioning shaft 9. The seat body 5 is a side-lying U-shaped structure, and a positioning sleeve 8 is installed on the upper surface of the horizontal section at the bottom of the seat body 5. The positioning sleeve 8 and the seat body 5 are positioned by a positioning shaft 9. A plurality of U-shaped notches 10 uniformly arranged in the circumferential direction are provided on the upper part of the positioning shaft 9, and a clamping ring 2 7 is connected to the outer surface of the plurality of U-shaped notches 10. The clamping ring 2 7 is locked by the clamping ring 1 6. The upper horizontal section of the seat body 5 is vertically fixedly connected with the bushing 4, and the upper end of the bushing 4 extends out of the seat body 5 and is connected to the locking nut 1 with a cover on the upper end. The pressure head 3 is movably inserted into the bushing 4 and the lower end can extend to the positioning sleeve 8 to tighten the quartz flexible accelerometer torquer stator; a rubber bushing 2 is provided at the bottom of the locking nut 1. The locking nut 1 is provided with scale marking points corresponding to the scales provided on the upper end surface of the seat body 5 .

[0089] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A manufacturing process for a quartz flexible accelerometer torquer stator, characterized by: The method comprises the following steps: 1) Welding of torquer stator assembly II and pendulum assembly Pass the lead wires of each terminal on the torquer stator assembly II through the ring groove of the pendulum assembly and weld them to the corresponding welding points of the pendulum assembly according to the welding definition of the quartz flexible accelerometer; 2) Welding and positioning of torquer stator assembly II and pendulum assembly After welding is completed, place the torquer stator assembly II at the bottom and the pendulum assembly at the top into the positioning sleeve of the combined fixture, so that the torquer stator assembly II contacts the end face of the positioning shaft of the combined fixture; 3) Positioning of torquer stator assembly I 3.1) Place the torquer stator assembly I onto the pendulum assembly along the inner hole of the assembly fixture positioning sleeve; 3.2) Install the modular fixture locating shaft, locating sleeve, clamping ring II, torquer stator assembly II, and pendulum assembly relative to the base of the modular fixture; 3.3) Insert the pressure head of the combined fixture into the corresponding hole of the combined fixture base, pre-sleeve the ring I on the outer circle of the pressure head, and then contact the pressure head with the torquer stator assembly I; 4) Combined clamp applies preload 4.1) Slowly tighten the lock nut of the assembly fixture until the torquer stator assembly I contacts the pendulum assembly. Use a willow stick to adjust the angular position of the torquer stator assembly II, pendulum assembly, and torquer stator assembly I, ensuring that the engraved line of the torquer stator assembly II, the notch of the pendulum assembly, and the engraved line of the torquer stator assembly I are aligned. 4.2) After adjusting the angle phase position, tighten the locking nut of the combination clamp; 5) Ring I positioning Remove the clamping ring 2 and the positioning shaft of the combined fixture, install the ring I with the notch in place, align the notch of the ring I with the engraved direction of the torquer stator assembly, and use the clamping ring I of the combined fixture to tighten the ring I; 6) Power on inspection 6.1) Connect the torquer stator assembly terminals to the servo circuit board using process wires according to the quartz flexible accelerometer wiring diagram. Perform a power-on test. The output voltage symmetry, zero bias, and return-to-zero error performance indicators under ±1g must meet the requirements. 6.2) If the performance index exceeds the tolerance, the preload force of the combined fixture on the torquer stator assembly should be adjusted, or the angular position of the torquer stator assembly II, pendulum assembly, and torquer stator assembly I should be fine-tuned until they meet the requirements. If they still do not meet the requirements, loosen the combined fixture and reassemble; 6.3) After the room temperature performance is qualified, the high and low temperature performance test and the performance test after the centrifugal test should meet the requirements; 7) Laser welding 7.1) Align the workbench and align the laser beam with the weld position; 7.2) First, symmetrically distribute 8 welding points along the circumference of the two welds. That is, 4 welding points are evenly distributed at the connection between the torquer stator assembly I and the ring I, and 4 welding points are evenly distributed at the connection between the torquer stator assembly II and the ring I. After welding the 4 welding points on one side, immediately turn the assembly fixture around and weld the 4 welding points on the other side. 7.3) Weld two sections along the circumference, one section each at the connection between the torquer stator assembly I and ring I, and one section at the connection between the torquer stator assembly II and ring I. The areas blocked by the assembly fixture are not welded for the time being; 7.4) Remove the modular fixture from the laser welding machine. The torquer stator assembly personnel will loosen the locking nut in the modular fixture and rotate the torquer stator assembly to the phase position until the weld originally covered by the modular fixture is completely exposed. Then tighten the locking nut in the modular fixture immediately. 7.5) After the weld seam covered by the modular fixture is exposed, complete the welding of the entire circle according to the above requirements; 7.6) After welding is completed, clean up the excess laser welding residue at the weld; 8) Recheck the performance indicators after disassembling the combined fixture; In the manufacturing process, a combination clamp is used for clamping operation, and the combination clamp comprises a locking nut (1), a pressure head (3), a bushing (4), a seat body (5), a clamping ring 1 (6), a clamping ring 2 (7), a positioning sleeve (8) and a positioning shaft (9). The seat body (5) is a side-lying U-shaped structure. A positioning sleeve (8) is installed on the upper surface of the bottom horizontal section of the seat body (5). The positioning sleeve (8) and the seat body (5) are positioned by the positioning shaft (9). The upper part of the positioning shaft (9) is provided with a plurality of U-shaped notches (10) uniformly arranged in the circumferential direction. The outer surface of the plurality of U-shaped notches (10) is connected to the clamping ring 2 (7). The clamping ring 2 (7) is locked by the clamping ring 1 (6), the upper horizontal section of the seat body (5) is vertically fixedly connected with the bushing (4), and the upper end of the bushing (4) extends out of the seat body (5) and is connected to the locking nut (1) with a cover provided on the upper end, the pressure head (3) is movably inserted into the bushing (4) and the lower end can extend toward the positioning sleeve (8) to tighten the stator of the quartz flexible accelerometer torque device.

2. The manufacturing process of a quartz flexible accelerometer torquer stator according to claim 1, characterized in that: A rubber bushing (2) is provided at the inner bottom of the locking nut (1).

3. The manufacturing process of a quartz flexible accelerometer torquer stator according to claim 1, characterized in that: During steps 1) to 4), the clamping ring 2 (7) and the positioning sleeve (8) in the combined clamp are used before the ring I is assembled; after the ring I is assembled, the clamping ring 1 (6) in the combined clamp is used, that is, the clamping ring 2 (7), the positioning sleeve (8) and the clamping ring 1 (6) in the combined clamp are used in different assembly stages.

4. The manufacturing process of a quartz flexible accelerometer torquer stator according to claim 1, characterized in that: The final use state of the torquer stator assembly is to offset the repulsive force of the structural magnetic field by laser welding the ring I with the torquer stator assembly I and the torquer stator assembly II.

5. The manufacturing process of a quartz flexible accelerometer torquer stator according to claim 1 or 3, characterized in that: The bottom hole of the seat body (5) in the combined fixture is used in conjunction with the laser welding fixture.

6. The manufacturing process of a quartz flexible accelerometer torquer stator according to claim 3, characterized in that: After laser welding is completed, clean the laser welding seam of the torquer stator assembly.

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