A pendulum assembly adjustment device and adjustment method

Abstract

This invention provides a pendulum assembly adjustment device and method. The device includes an adjustment fixture and a laser cutting device. The adjustment fixture includes a pressure loading frame, a pressure bolt, a detection cap, and a pendulum assembly fixing seat. The pressure loading frame includes two fixing parts for mounting the pendulum assembly fixing seat and the pressure bolt. The pendulum assembly fixing seat includes a positioning bracket for placing the pendulum assembly and a magnet placed in the central cavity of the positioning bracket. The detection cap is placed on the pendulum assembly and is equipped with at least two capacitance measuring devices and at least two through slots. The capacitance measuring devices are used to detect the position of the central pendulum and the symmetrical gold area along the pendulum axis. The through slots are used for laser transmission to adjust the central pendulum. The pressure bolt is applied to the detection cap. The central axes of the pendulum assembly fixing seat, the detection cap, and the pressure bolt are collinear. The laser cutting device is used to output laser light to adjust the central pendulum. This invention solves the problem of flat bridge torsion by measuring the torsion of the flat bridge in real time and adjusting the center of gravity of the central pendulum using laser adjustment.

Description

Technical Field

[0001] This invention belongs to the field of accelerometer component assembly technology, and relates to a method for testing and optimizing the pendulum performance of a pendulum assembly, specifically relating to a tuning device and tuning method for a quartz flexible accelerometer pendulum assembly. Background Technology

[0002] The accelerometer's detection mass pendulum, also known as the pendulum assembly, consists of two torque converter moving coils symmetrically connected at the center of the pendulum plate. The center of the pendulum plate is connected to its outer ring via an extremely thin quartz bridge. The pendulum assembly, along with the upper and lower torque converters, forms a force feedback device. When acceleration is applied to the input shaft, an acceleration torque is generated. The servo circuit receives the signal and generates a feedback current. This current is transmitted through the terminal of the lower torque converter and the wire connecting the terminal to the outer ring of the pendulum plate, passing through the gold-plated layer of the pendulum plate to the moving coil of the torque converter. Under the influence of the permanent magnetic field of the torque converter, a restoring torque is generated, causing the detection mass pendulum to return to its original equilibrium position. The meter core is composed of the upper torque converter, the pendulum assembly, and the lower torque converter connected by a band. Each of the upper torque converter, the pendulum assembly, and the lower torque converter has a circular outer circumference of approximately equal diameter. The pendulum assembly is held in the middle by the upper and lower torque converters. Ideally, after the accelerometer movement is assembled, the central axes of the upper and lower torquers should coincide with the central axis of the pendulum assembly, and the pendulum assembly should move along these central axes during operation, with its central axis always coinciding with the central axes of the upper and lower torquers. However, due to the influence of parts machining accuracy and component assembly accuracy, the center of gravity of the pendulum assembly is not on its pendulum axis, causing the quartz bridge to twist during the pendulum assembly's movement along the input axis, affecting the product's output accuracy.

[0003] Currently, the center of gravity of the pendulum assembly can only be controlled through two methods: increasing the precision requirements of parts machining and improving the precision requirements of assembly. However, unilaterally pursuing higher parts machining precision directly leads to increased costs, and the cumulative error factors in the assembly process are difficult to completely eliminate. In actual production, the accelerometer's flat bridge often twists during operation due to the offset of the pendulum's center of gravity, affecting the product's measurement accuracy. Therefore, there is an urgent need for a method that can effectively reduce the twisting of the pendulum assembly's flat bridge during product operation. Summary of the Invention

[0004] To address the problem of pendulum component flat bridge torsion during operation in existing quartz flexural accelerometers, this invention provides a pendulum component adjustment device and method. The device employs a pendulum component adjustment fixture, pressure measuring equipment, capacitance measuring equipment, and high-precision laser cutting equipment to measure the flat bridge torsion in real time. By adjusting the central pendulum, the device effectively controls the characteristics of the pendulum component after assembly.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0006] This invention provides a pendulum component adjustment device, including an adjustment fixture and a laser cutting device;

[0007] The adjustment fixture includes a pressure loading frame, pressure bolts, a detection cap, and a swing assembly fixing seat;

[0008] The pressure loading frame includes two fixing parts;

[0009] The pendulum component fixing seat is installed in a fixing part of the pressure loading frame. The pendulum component fixing seat includes a positioning bracket for placing the pendulum component and a magnet placed in the central cavity of the positioning bracket.

[0010] The detection cap is placed on the pendulum assembly and is equipped with at least two capacitance measuring devices and at least two through slots. The capacitance measuring devices are used to detect the position of the central pendulum of the pendulum assembly and the position of the gold area symmetrical along the pendulum axis. The through slots are used for laser to pass through and adjust the central pendulum.

[0011] The pressure bolt is installed in another fixing part of the pressure loading frame and applies pressure to the detection cap;

[0012] The central axes of the swing assembly fixing seat, the detection cap, and the pressure bolt are collinear.

[0013] The laser cutting equipment is used to output laser to adjust the center pendulum.

[0014] Furthermore, the detection cap includes a second outer shell, two capacitance measuring devices, and two through slots. The capacitance measuring devices are capacitance sensors. The second outer shell is cylindrical and has two axial mounting holes at a position symmetrical to the central axis. The mounting holes are used to mount the capacitance sensors. The detection areas of the two capacitance sensors correspond to two gold areas of equal area that are symmetrical to the pendulum axis of the pendulum assembly. The line connecting the centers of the two through slots is parallel to or overlaps with the two lines connecting the centers of the two mounting holes. The two through slots are equidistant from the central axis of the second outer shell.

[0015] Furthermore, a pressure measuring device is also installed on the detection cap, and the pressure bolt presses on the pressure measuring device of the detection cap; the pressure measuring device is a pressure sensor and a pressure bearing; a first groove is provided on one end face of the second housing, and the pressure sensor and pressure bearing are installed in the first groove; a second groove and a third groove are provided on the other end face of the second housing along the central axis, the second groove is far away from the end face, the inner diameter is larger than the outer diameter of the moving ring of the swing assembly, and the depth is larger than the height of the moving ring of the swing assembly, and the third groove is close to the end face, and the inner diameter is equal to the inner diameter of the outer ring of the swing assembly.

[0016] Furthermore, the pressure loading frame includes a bottom edge and an upper cantilever parallel to the bottom edge, and the bottom edge and the upper cantilever are provided with openings with collinear central axes; the pressure bolt is installed in the opening of the upper cantilever of the pressure loading frame, and the two are engaged by a threaded structure; the pendulum assembly fixing seat is placed in the opening of the bottom edge; the width of the upper cantilever of the pressure loading frame at the opening position is 1mm to 4mm smaller than the maximum outer edge distance between the central pendulum and the pendulum axis in the direction perpendicular to the pendulum axis of the pendulum assembly.

[0017] Furthermore, the pressure bolt includes a first housing, a screw plug, a spring, and a pressure column; the first housing is a cylindrical structure with a base plate at one end, and the base plate has a central hole; the pressure column, spring, and screw plug are sequentially installed inside the first housing, one end of the pressure column passes through the central hole of the base plate and extends out of the first housing, and the screw plug presses the other end of the pressure column against the base plate by the spring.

[0018] Furthermore, the positioning support includes a small columnar body and a large columnar body that are collinear with their central axes and fixedly connected; the small columnar body is used to connect with the bottom edge opening of the pressure loading frame; the exposed end face of the large columnar body is provided with a cavity for supporting the outer ring of the pendulum assembly and accommodating the magnet; the cavity of the large columnar body includes four sequentially connected cavities, a first cavity, a second cavity, a third cavity, and a fourth cavity that are coaxial with the positioning support, starting from the end face; the inner diameter of the first cavity is the same as the outer diameter of the pendulum assembly, the inner diameter of the second cavity is smaller than the inner diameter of the outer ring of the pendulum assembly but larger than the outer diameter of the central pendulum of the pendulum assembly, the inner diameter of the third cavity is larger than the inner diameter of the moving coil of the pendulum assembly, the inner diameter of the fourth cavity is larger than the third cavity, and the sum of the heights of the third cavity and the fourth cavity is greater than the height of the moving coil of the pendulum assembly.

[0019] Furthermore, the depth of the first cavity is less than the thickness of the swing plate; the depth of the second cavity is the same as the depth of the third groove, between 0.02mm and 0.5mm; the height of the third cavity is between 2mm and 6mm; the inner diameter of the fourth cavity is 2mm to 8mm smaller than the outer diameter of the positioning bracket; the sum of the heights of the first cavity, second cavity, third cavity, and fourth cavity is less than the height of the large columnar body by 1mm to 5mm; the positioning bracket and the magnet are made of the same material as the torque device.

[0020] Furthermore, the positioning bracket is provided with blind holes or through holes at the location corresponding to the laser cutting center pendulum, for accommodating the debris that falls off the laser cutting center pendulum.

[0021] The present invention also provides a method for adjusting a pendulum component, comprising the following steps:

[0022] Assemble the pendulum component onto the pendulum component positioning seat;

[0023] Adjust the detection cap to make its capacitance sensor and through slot symmetrical about the pendulum assembly axis;

[0024] Adjust the pressure applied to the test cap by the pressure bolt;

[0025] Apply current to the pendulum assembly to drive the central pendulum to swing, detect the difference in output signals of the two capacitive sensors, and determine the direction of the central pendulum's offset.

[0026] A laser is used to penetrate the exposed portion of the pendulum assembly on the side where the center of gravity of the pendulum is off-center, until the difference in the output signals of the two capacitive sensors meets the requirements.

[0027] Furthermore, the pendulum axis of the pendulum assembly is parallel to the bottom edge of the pressure loading frame; the adjustment fixture is placed on the cutting table of the laser cutting equipment; the laser is a picosecond laser or a femtosecond laser; when the laser adjustment pendulum assembly is in the center, it passes through the outer edge of the cutting center pendulum in a scribing manner.

[0028] The beneficial effects of this invention compared to the prior art are as follows:

[0029] The pendulum assembly adjustment device provided by this invention can accurately measure the positional difference between the two sides of the central pendulum of the pendulum assembly during the swing process and evaluate the torsional state of the pendulum assembly's flat bridge; it can simulate the pressure and coil current changes of the pendulum assembly during the actual operation of the accelerometer, and the measurement data is closer to the actual working state; when the pendulum assembly is trimmed by precision machining, it is not necessary to unload the pendulum assembly from the fixture, and after trimming the central pendulum by laser cutting, the pendulum assembly characteristics can be directly measured.

[0030] The adjustment method provided by this invention is simple to operate and highly repeatable. Adjusting the pendulum assembly can not only effectively eliminate the impact of the pendulum assembly's center of gravity deviation on the accelerometer's performance, thereby improving product accuracy, but also significantly increase the yield of subsequent watch core assembly and reduce production costs. Attached Figure Description

[0031] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of the pendulum component adjustment device provided in a specific embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the structure of the pendulum component adjustment fixture provided in a specific embodiment of the present invention;

[0034] Figure 3 for Figure 2 A schematic diagram of the structure of the pressure bolt in the middle;

[0035] Figure 4 for Figure 2 A schematic diagram of the structure of the detection cap in the image;

[0036] Figure 5 for Figure 2 A schematic diagram of the positioning seat of the pendulum component.

[0037] The above figures include the following reference numerals:

[0038] 1. Pressure loading frame; 2. Pressure bolt; 3. Detection cap; 4. Swing assembly positioning seat; 5. Swing assembly; 2.1. First outer shell; 2.2. Plug; 2.3. Spring; 2.4. Pressure column; 3.1. Second outer shell; 3.2. First capacitive sensor; 3.3. Second capacitive sensor; 3.4. Pressure sensor; 3.5. Pressure bearing; 4.1. Positioning bracket; 4.2. Magnet. Detailed Implementation

[0039] Specific embodiments of the present invention will now be described in detail. In the following description, specific details are set forth for purposes of explanation and not limitation, in order to aid in a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced in other embodiments departing from these specific details.

[0040] It should be noted that, in order to avoid obscuring the invention with unnecessary details, only the device structure and / or processing steps closely related to the solution of the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0041] The accelerometer's pendulum assembly includes a pendulum plate, a first moving coil, and a second moving coil. The pendulum plate includes a central pendulum, an outer ring coaxial with the central pendulum, and a flat bridge connecting the central pendulum and the outer ring. The first and second moving coils are mounted on opposite sides of the central pendulum, and the central axes of the first moving coil, the pendulum plate, and the second moving coil are collinear. The straight line passing through the center of the flat bridge and the center of the outer ring on the plane containing the pendulum plate is the pendulum axis, and the pendulum plate structure is symmetrical about the pendulum axis.

[0042] This invention provides a pendulum assembly adjustment device, comprising an adjustment fixture and a laser cutting device. The adjustment fixture includes a pressure loading frame 1, a pressure bolt 2, a detection cap 3, and a pendulum assembly fixing seat 4. The pressure loading frame 1 includes two fixing parts. The pendulum assembly fixing seat 4 is installed in one fixing part of the pressure loading frame 1 and includes a positioning bracket for placing the pendulum assembly and a magnet placed at the center of the positioning bracket. The detection cap 3 is placed on the pendulum assembly and is equipped with at least two capacitance measuring devices for detecting the position of the central pendulum and the symmetrical gold area along the pendulum axis. The detection cap 3 is also provided with at least two through slots for laser to pass through and adjust the central pendulum. The pressure bolt 2 is installed in the other fixing part of the pressure loading frame 1 and applies pressure to the detection cap 3. The central axes of the pendulum assembly fixing seat 4, the pendulum assembly, the detection cap 3, and the pressure bolt 2 are collinear. The laser cutting device is used to output laser to adjust the central pendulum.

[0043] In the aforementioned adjustment fixture, the pressure loading frame is used to position the pressure bolt and the pendulum assembly positioning seat, and to provide rigid support for the pressure bolt and the pendulum assembly positioning seat; the pressure bolt is used to provide pressure between the detection cap, the pendulum assembly, and the pendulum assembly positioning seat; the detection cap is equipped with a capacitive sensor to detect the position of the central pendulum of the pendulum assembly and the gold area symmetrically positioned along the pendulum axis; the pendulum assembly positioning seat is used to fix the pendulum assembly and to provide driving force to the energized coil of the pendulum assembly through the magnet installed on the pendulum assembly positioning seat.

[0044] The pendulum assembly adjustment device provided by the present invention measures the positional difference between the two sides of the central pendulum of the pendulum assembly during the swing process by adjusting the clamp, determines the tortuous state of the flat bridge of the pendulum assembly, cuts the central pendulum by laser cutting equipment, adjusts the center of gravity of the central pendulum, and solves the problem of flat bridge tortuosity.

[0045] Furthermore, a pressure measuring device is installed at the center of one side of the adjustment fixture's test cap, and a pressure bolt is applied to the pressure measuring device on the test cap. The pressure measuring device on the test cap measures the pressure between the test cap, the pendulum assembly, and the pendulum assembly positioning seat. By measuring the pressure between the test cap, the pendulum assembly, and the pendulum assembly positioning seat in real time using the pressure measuring device, the pressure experienced by the pendulum assembly during the actual operation of the accelerometer is accurately simulated.

[0046] When adjusting the pendulum assembly using the aforementioned adjustment device, the outer ring of the pendulum assembly's pendulum plate is placed on the positioning support of the fixed base, and the second moving coil of the pendulum assembly is placed outside the magnet, without contacting the magnet. A detection cap is placed on the outer ring of the pendulum assembly, without contacting the first moving coil. A simulated current is applied to the outer ring of the pendulum assembly. When the pendulum assembly is stationary, the central pendulum hangs down. After applying the simulated current to the outer ring, the second moving coil interacts with the magnet, causing the central pendulum to swing. The detection cap can detect the position of the central pendulum and the symmetrical gold area along the pendulum axis, determining whether the pendulum assembly's flat bridge is twisted during operation. If the flat bridge is twisted, a laser cutting device outputs a laser beam that passes through the detection cap to cut the central pendulum, adjusting its center of gravity and resolving the flat bridge twisting problem.

[0047] The present invention also provides a method for adjusting a pendulum component, comprising the following steps:

[0048] Assemble the pendulum assembly onto the pendulum assembly positioning seat of the adjustment fixture;

[0049] Adjust the detection cap to make its capacitance sensor and through slot symmetrical about the pendulum assembly axis;

[0050] Adjust the pressure applied to the test cap by the pressure bolt;

[0051] Apply current to the pendulum assembly to drive the central pendulum to swing, detect the difference in output signals of the two capacitive sensors, and determine the direction of the central pendulum's offset.

[0052] A laser is used to penetrate the exposed portion of the pendulum assembly on the side where the center of gravity of the pendulum is off-center, until the difference in the output signals of the two capacitive sensors meets the requirements.

[0053] The adjustment method of this invention is simple to operate and highly repeatable. Adjusting the pendulum component can not only effectively eliminate the impact of the pendulum component's center of gravity deviation on the accelerometer performance, thereby improving product accuracy, but also significantly improve the yield of subsequent watch core assembly and reduce production costs.

[0054] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and a specific embodiment.

[0055] like Figure 1 As shown, the pendulum component adjustment device provided by the present invention includes a precision laser cutting device, a pendulum component adjustment fixture, a pressure measuring device, a capacitance measuring device, and a power supply. The precision laser cutting device, pressure measuring device, capacitance measuring device, and power supply can use standard equipment. The pendulum component adjustment fixture includes a pressure loading frame 1, a pressure bolt 2, a detection cap 3, and a pendulum component positioning seat 4.

[0056] (1) Pressure loading frame

[0057] like Figure 2As shown, the pressure loading frame 1 includes a bottom edge and an upper cantilever parallel to the bottom edge. The upper cantilever of the pressure loading frame 1 has a threaded hole for fixing the pressure bolt 2. The width of the upper cantilever at the threaded hole position is 1mm to 4mm smaller than the maximum distance between the outer edges of the central pendulum of the pendulum assembly perpendicular to the pendulum axis, leaving operating space for subsequent adjustment of the central pendulum. The bottom edge of the pressure loading frame has a through hole for fixing the pendulum assembly mounting base 4. The central axes of the threaded hole and the through hole are collinear and perpendicular to the bottom edge of the pressure loading frame.

[0058] (2) Pressure bolt

[0059] like Figure 3 As shown, the pressure bolt 2 has a spring plunger structure, used to provide pressure between the test cap 3, the pendulum assembly positioning seat 4, and the outer ring of the pendulum assembly 5 when testing the performance of the pendulum assembly. The pressure bolt 2 includes a first housing 2.1, a screw plug 2.2, a spring 2.3, and a pressure column 2.4. The first housing 2.1 is a cylindrical structure with a base plate at one end, and the base plate has a central hole. The pressure column 2.4, the spring 2.3, and the screw plug 2.2 are sequentially installed inside the first housing 2.1. One end of the pressure column 2.4 passes through the central hole of the base plate and extends out of the first housing 2.1. The screw plug 2.2 presses the other end of the pressure column 2.4 against the base plate of the first housing 2.1 through the spring 2.3.

[0060] The first outer casing 2.1 has an internal thread on its inner side at the open end (i.e., the end furthest from the base plate), with a thread width between 5 mm and 25 mm. The plug 2.2 is a cylindrical structure with external threads, and it is connected to the open end of the first outer casing 2.1 via a threaded connection. The inner diameter of the center hole in the base plate is 0.5 mm to 3 mm smaller than the inner diameter of the internal thread structure of the first outer casing 2.1.

[0061] Spring 2.3 is a compression spring with a diameter of 10mm to 30mm, used to provide pressure. The outer diameter of spring 2.3 is slightly smaller than the inner diameter of the first housing 2.1.

[0062] The pressure column 2.4 has a stepped, T-shaped variable-diameter structure. The pressure column 2.4 includes a fixed head section and a tail section. The outer diameter of the head section is larger than that of the tail section. The tail section passes through the central hole of the base plate of the first housing 2.1, and the head section is confined within the cavity of the pressure bolt 2. Preferably, the outer diameter of the head section is slightly smaller than the inner diameter of the first housing 2.1, but larger than the inner diameter of the central hole of the base plate and the outer diameter of the spring 2.3. The outer diameter of the tail section of the pressure column 2.4 is slightly smaller than the inner diameter of the central hole of the base plate and has graduations to identify the length of the pressure column 2.4 exposed outside the first housing 2.1.

[0063] The pressure bolt 2 is provided with external threads and is fitted into the cantilevered threaded hole on the pressure loading frame 1. Preferably, in order to limit the pressure bolt 2 in the cantilevered threaded hole on the pressure loading frame 1, the outer surface of the pressure bolt 2 forms a stepped diameter-changing structure, that is, a stepped structure with a larger outer diameter is provided at the end away from the base plate. The smaller outer diameter portion of the pressure bolt 2 is provided with an external thread structure, and the pressure bolt 2 is installed in the cantilevered threaded hole on the pressure loading frame 1 through the external thread structure.

[0064] Pressure is applied downwards by adjusting the height of the pressure bolt 2 relative to the upper cantilever.

[0065] (3) Testing cap

[0066] like Figure 4 As shown, the detection cap 3 includes a second outer shell 3.1, a first capacitive sensor 3.2, a second capacitive sensor 3.3, a pressure sensor 3.4, and a pressure bearing 3.5.

[0067] The second outer shell 3.1 is cylindrical, with an outer diameter similar to that of the pendulum assembly 5. The second outer shell 3.1 has three blind slots (blind slots are recessed grooves on the end face of a cylinder) arranged along its central axis, including a top circular hole blind slot, a bottom circular hole blind slot, and a bottom outer ring blind slot. The inner diameter of the top circular hole blind slot is larger than the outer diameter of the tail section of the pressure column; the inner diameter of the bottom circular hole blind slot is slightly larger than the outer diameter of the first moving coil of the pendulum assembly 5, and the depth of the bottom circular hole blind slot is greater than the height of the first moving coil of the pendulum assembly 5; the inner diameter of the bottom outer ring blind slot is similar to the inner diameter of the outer ring 5 of the pendulum assembly, and its depth is between 0.02 mm and 0.5 mm. The aforementioned bottom outer ring blind slot has an opening at the lead-out position of the pendulum assembly 5 for the lead-out wire to pass through.

[0068] Two mounting holes are symmetrically formed on the diameter of the first housing 3.1, between 4mm and 15mm from the central axis of the first housing 3.1, to mount the first capacitive sensor 3.2 and the second capacitive sensor 3.3, respectively. On a line overlapping or parallel to the line connecting the centers of the two mounting holes, away from the central axis of the first housing 3.1, there are two through slots with a length of 1mm to 10mm and a width of 0.5mm to 2mm (the width of the through slots is along the diameter of the first housing, and the length is perpendicular to the diameter of the first housing). The two through slots extend along the central axis of the first housing 3.1 and are symmetrical about the perpendicular plane of the two mounting holes.

[0069] The position and shape parameters of the mounting holes and through slots should meet the following requirements: when the central axis of the pendulum assembly 5 is collinear with the central axis of the detection cap 3, and the pendulum axis of the pendulum assembly 5 is perpendicular to the line connecting the centers of the two mounting holes, the detection area of ​​the two capacitive sensors includes two gold-plated areas of equal area, symmetrical about the pendulum axis of the pendulum assembly, and the area including the outer edge of the central pendulum of the pendulum assembly can be observed perpendicularly through the two through slots. The two capacitive sensors are two independent capacitive sensors with the same specifications and height. With the help of the above-mentioned capacitive sensors, the position status of the corresponding gold area on the central pendulum of the pendulum assembly can be detected during the adjustment process. In actual operation, the two capacitive sensors will be connected to the data acquisition and processing equipment through lead wires. The pressure sensor 3.4 is placed in the blind slot of the top circular hole, and the pressure measuring platform of the pressure sensor 3.4 is equipped with a pressure bearing 3.5.

[0070] During operation, the test cap 3 is fastened to the outer ring of the pendulum assembly 5. An opening is reserved at the edge of the blind groove on the bottom of the outer ring of the test cap 3 for the pendulum assembly 5 lead wire to pass through. The lead wire connects the outer ring of the pendulum assembly 5 to the power supply and applies a simulated current to the pendulum assembly 5 through the lead wire.

[0071] (4) Positioning seat of pendulum component

[0072] like Figure 5 As shown, the pendulum assembly positioning seat 4 includes a positioning bracket 4.1 and a magnet 4.2. The positioning bracket 4.1 includes two small cylindrical bodies and a large cylindrical body with different outer diameters, fixedly connected. The outer diameter of the small cylindrical body is smaller than that of the large cylindrical body, and the central axes of the two cylindrical bodies are collinear. The positioning bracket 4.1 is connected to the pressure loading frame 1 through the through hole of the small cylindrical body. The large cylindrical body is a magnetically conductive cylinder with an outer diameter slightly larger than that of the pendulum assembly 5. Starting from the end away from the small cylindrical body, four cavities—a first cavity, a second cavity, a third cavity, and a fourth cavity—are arranged sequentially and coaxially with the positioning bracket 4.1. The inner diameter of the first cavity is approximately equal to the outer diameter of the pendulum assembly 5, and its depth is between 0.2 mm and 5 mm. The inner diameter of the second cavity is slightly smaller than the inner diameter of the outer ring of the pendulum assembly 5 but larger than the outer diameter of the central pendulum of the pendulum assembly 5, and the depth of the second cavity is approximately equal to the depth of the blind groove of the bottom outer ring. The height of the third cavity is between 2mm and 6mm, and its inner diameter is slightly larger than the inner diameter of the second moving coil of the pendulum assembly 5. The inner diameter of the fourth cavity is slightly larger than that of the third cavity and 2mm to 8mm smaller than the outer diameter of the positioning bracket 4.1. The sum of the heights of the third and fourth cavities is greater than the height of the second moving coil of the pendulum assembly 5, and the sum of the heights of the first, second, third, and fourth cavities is less than the height of the large cylindrical body by 1mm to 5mm. The magnet 4.2 is a cylinder of permanent magnet material, whose outer diameter is slightly smaller than the inner diameter of the second moving coil of the pendulum assembly 5, its height is greater than the height of the second moving coil of the pendulum assembly 5, and its height is smaller than the sum of the heights of the third and fourth cavities. The magnet 4.2 is connected to the positioning bracket 4.1 by welding or gluing, and after connection, the central axes of the magnet 4.2 and the positioning bracket 4.1 are collinear.

[0073] At the two through slot positions of the pendulum component fixing seat 4 corresponding to the first outer shell 3.1 (i.e. the laser-cut part of the central pendulum), there are two holes with a diameter > Φ3mm (which can be blind holes with a depth > 2mm or through holes). The debris from the laser-cut central pendulum can fall into the above holes, avoiding the glass fragments from interfering with the pendulum component characteristic test results.

[0074] The pendulum component adjustment method provided by this invention includes the following steps:

[0075] 1. Assemble the pendulum assembly onto the adjustment fixture;

[0076] Step 1: Place the pressure loading frame 1 on a horizontal surface with the threaded hole facing upwards;

[0077] Step 2: Place the pendulum assembly with the lead wire connected on the pendulum assembly positioning seat 4. At this time, the pendulum assembly 5 cooperates with the first cavity through its outer periphery.

[0078] Step 3: The pendulum component positioning seat 4, which is loaded with pendulum component 5, is installed into the bottom through hole of the pressure loading frame 1 through the small column. Adjust the direction of the pendulum component positioning seat 4 so that the pendulum axis of the pendulum component 5 is parallel to the bottom edge of the pressure loading frame (that is, the pendulum component 5 is placed symmetrically about the vertical plane of the adjustment fixture). At this time, when looking down at the pressure loading frame from above, the center pendulum of the pendulum component 5 should be partially exposed, and the exposed part should be symmetrical.

[0079] Step 4: With the detection surfaces of the two capacitive sensors close to the center of the pendulum assembly 5 and the line connecting the centers of the two capacitive sensors perpendicular to the pendulum axis of the pendulum assembly, fasten the detection cap 3 to the pendulum assembly 5. During the fastening process, ensure that the detection cap 3 and the center axis of the pendulum assembly 5 coincide and that the lead wire of the pendulum assembly 5 passes through the lead wire opening of the bottom outer ring blind groove. At this time, when looking down at the pressure loading frame from above, the center of the pendulum assembly 5 should be partially exposed in the through groove, and the exposed part should be symmetrical.

[0080] Step 5: Assemble the pressure bolt 2, pass the tail section of the pressure column 2.4 through the through hole in the bottom plate of the first housing 2.1, place the spring 2.3 on the head section of the pressure column 2.4, and screw the plug 2.2 into the open end of the first housing 2.1;

[0081] Step 6: Connect the pressure bolt 2 to the pressure loading frame 1 with the pressure column 2.4 pointing downwards. The two are threaded together. Rotate the pressure bolt 2 until the pressure column 2.4 contacts the pressure bearing 3.5. Continue rotating the pressure bolt 2 while observing the measurement value of the pressure measuring device connected to the pressure sensor 3.4. Stop rotating the pressure bolt 2 when the measurement value reaches the expected value.

[0082] 2. Adjust the central pendulum of the pendulum component.

[0083] Step 1: Connect the pendulum assembly, capacitive sensor, and pressure sensor to the external device, apply an analog current to the pendulum assembly, detect the difference in output signals between the two capacitive sensors, evaluate the tilt of the plane where the central pendulum of the pendulum assembly is located during the movement of the central pendulum, and determine the direction of the offset of the center of gravity of the central pendulum.

[0084] Step 2: Place the pendulum assembly adjustment fixture on the cutting table of the high-precision laser cutting equipment, and use the laser to cut and trim the exposed part of the pendulum assembly on the side where the center of gravity of the pendulum is off, until the difference in the output signals of the two capacitive sensors disappears or is reduced to an acceptable range.

[0085] After laser cutting and repairing the pendulum, the pendulum component characteristics can be measured directly.

[0086] In a preferred embodiment of the present invention, the range of motion of the pressure column on the pressure bolt is 20mm, and the maximum pressure that the spring can bear is 200N; the capacitive sensor end face on the detection cap has a circular outer diameter of 5mm; the inner diameter of the blind groove on the outer ring at the bottom of the detection cap is 0.6mm smaller than the inner diameter of the outer ring of the pendulum assembly, and the depth is 0.3mm; the through groove on the detection cap is 5mm long and 2mm wide; the outer diameter of the pendulum assembly positioning seat is 1mm larger than the outer diameter of the pendulum assembly; the outer diameter of the magnet on the pendulum assembly positioning seat is 0.6mm smaller than the inner diameter of the torque coil on the pendulum assembly; the inner diameter of the third cavity of the pendulum assembly positioning seat is 0.6mm larger than the outer diameter of the torque coil on the pendulum assembly; the depth of the first cavity of the pendulum assembly positioning seat is 0.5mm; the depth of the second cavity of the pendulum assembly positioning seat is 0.3mm; after the pendulum assembly is placed on the pendulum assembly positioning seat, the distance between the magnet and the bottom surface of the torque coil on the pendulum assembly is 0.3mm; the inner diameter of the fourth cavity of the pendulum assembly positioning seat is 17mm.

[0087] Preferably, the positioning bracket and magnet are made of the same material as the torque device. Specifically, the positioning bracket is made of Invar alloy; the magnet is an assembly with an AlNiCo or Samarium Cobalt magnetic material at the bottom and a nickel-iron alloy (high magnetic permeability material) sheet attached to the top. The outer diameter of the magnetic material and the nickel-iron alloy sheet are the same, and the magnet structure is consistent with that of the torque device.

[0088] When measuring the state of the pendulum assembly, the pressure between the detection cap, the pendulum assembly, and the pendulum assembly positioning seat is 100N; when detecting the state of the pendulum assembly, the current input to the pendulum assembly has a sinusoidal change.

[0089] The laser equipment used for trimming the center pendulum of the pendulum assembly is a picosecond laser or a femtosecond laser, or other types of lasers can be used; when trimming the center pendulum of the pendulum assembly, the outer edge of the center pendulum is cut through by scribing.

[0090] By applying the pendulum assembly adjustment method of the present invention during the production of quartz flexible accelerometers, the impact of the pendulum assembly center pendulum outer dimensions or torque coil assembly errors on accelerometer performance can be reduced, thereby improving product accuracy, increasing product assembly yield, reducing component waste, and saving production costs.

[0091] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0092] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0093] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0094] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0095] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A pendulum component adjustment device, characterized in that, This includes adjustment fixtures and laser cutting equipment; The adjustment fixture includes a pressure loading frame, pressure bolts, a detection cap, and a swing assembly fixing seat; The pressure loading frame includes two fixing parts; The pendulum component fixing seat is installed in a fixing part of the pressure loading frame. The pendulum component fixing seat includes a positioning bracket for placing the pendulum component and a magnet placed in the central cavity of the positioning bracket. The detection cap is placed on the pendulum assembly and is equipped with at least two capacitance measuring devices and at least two through slots. The capacitance measuring devices are used to detect the position of the central pendulum of the pendulum assembly and the position of the gold area symmetrical along the pendulum axis. The through slots are used for laser to pass through and adjust the central pendulum. The pressure bolt is installed in another fixing part of the pressure loading frame and applies pressure to the detection cap; The central axes of the swing assembly fixing seat, the detection cap, and the pressure bolt are collinear. The laser cutting equipment is used to output laser to adjust the center pendulum.

2. The pendulum component adjustment device according to claim 1, characterized in that, The detection cap includes a second outer shell, two capacitance measuring devices, and two through slots. The capacitance measuring devices are capacitance sensors. The second outer shell is cylindrical and has two axial mounting holes at a position symmetrical to its central axis. The mounting holes are used to mount the capacitance sensors. The detection areas of the two capacitance sensors correspond to two gold areas with equal areas and symmetrical to the pendulum axis of the pendulum assembly. The line connecting the centers of the two through slots is parallel to or overlaps with the two lines connecting the centers of the two mounting holes. The two through slots are equidistant from the central axis of the second outer shell.

3. The pendulum component adjustment device according to claim 2, characterized in that, The detection cap is also equipped with a pressure measuring device, and the pressure bolt presses on the pressure measuring device of the detection cap; the pressure measuring device is a pressure sensor and a pressure bearing; a first groove is provided on one end face of the second housing, and the pressure sensor and pressure bearing are installed in the first groove; a second groove and a third groove are provided on the other end face of the second housing along the central axis, the second groove is far away from the end face, the inner diameter is larger than the outer diameter of the moving ring of the swing assembly, and the depth is larger than the height of the moving ring of the swing assembly; the third groove is close to the end face, and the inner diameter is equal to the inner diameter of the outer ring of the swing assembly.

4. The pendulum component adjustment device according to claim 1, characterized in that, The pressure loading frame includes a bottom edge and an upper cantilever parallel to the bottom edge. The bottom edge and the upper cantilever are provided with openings with collinear central axes. The pressure bolt is installed in the opening of the upper cantilever of the pressure loading frame, and the two are engaged by a threaded structure. The pendulum assembly fixing seat is placed in the opening of the bottom edge. The width of the upper cantilever of the pressure loading frame at the opening position is 1mm to 4mm smaller than the maximum outer edge distance between the central pendulum and the pendulum axis in the direction perpendicular to the pendulum axis of the pendulum assembly.

5. The pendulum component adjustment device according to claim 1, characterized in that, The pressure bolt includes a first housing, a screw plug, a spring, and a pressure column; the first housing is a cylindrical structure with a base plate at one end, and the base plate has a central hole; the pressure column, spring, and screw plug are sequentially installed inside the first housing, one end of the pressure column passes through the central hole of the base plate and extends out of the first housing, and the screw plug presses the other end of the pressure column against the base plate by the spring.

6. The pendulum component adjustment device according to claim 3, characterized in that, The positioning support includes a small columnar body and a large columnar body that are collinear with their central axes and fixedly connected. The small columnar body is used to connect with the bottom opening of the pressure loading frame. The exposed end face of the large columnar body has a cavity for supporting the outer ring of the pendulum assembly and accommodating the magnet. The cavity of the large columnar body includes four sequentially connected cavities, a first cavity, a second cavity, a third cavity, and a fourth cavity that are coaxial with the positioning support. The inner diameter of the first cavity is the same as the outer diameter of the pendulum assembly. The inner diameter of the second cavity is smaller than the inner diameter of the outer ring of the pendulum assembly but larger than the outer diameter of the central pendulum of the pendulum assembly. The inner diameter of the third cavity is larger than the inner diameter of the moving ring of the pendulum assembly. The inner diameter of the fourth cavity is larger than that of the third cavity. The sum of the heights of the third and fourth cavities is greater than the height of the moving ring of the pendulum assembly.

7. The pendulum component adjustment device according to claim 6, characterized in that, The depth of the first cavity is less than the thickness of the swing plate; the depth of the second cavity is the same as the depth of the third groove, between 0.02mm and 0.5mm; the height of the third cavity is between 2mm and 6mm; the inner diameter of the fourth cavity is 2mm to 8mm smaller than the outer diameter of the positioning bracket; the sum of the heights of the first cavity, second cavity, third cavity, and fourth cavity is less than the height of the large columnar body by 1mm to 5mm; the positioning bracket and the magnet are made of the same material as the torque device.

8. The pendulum component adjustment device according to claim 1, characterized in that, The positioning bracket is provided with blind holes or through holes at the location corresponding to the laser cutting center pendulum, for accommodating the debris that falls off the laser cutting center pendulum.

9. A method for adjusting a pendulum component, characterized in that, The method using the pendulum assembly adjustment device according to any one of claims 1 to 8 includes the following steps. Assemble the pendulum component onto the pendulum component positioning seat; Adjust the detection cap to make its capacitance sensor and through slot symmetrical about the pendulum assembly axis; Adjust the pressure applied to the test cap by the pressure bolt; Apply current to the pendulum assembly to drive the central pendulum to swing, detect the difference in output signals of the two capacitive sensors, and determine the direction of the central pendulum's offset. A laser is used to penetrate the exposed portion of the pendulum assembly on the side where the center of gravity of the pendulum is off-center, until the difference in the output signals of the two capacitive sensors meets the requirements.

10. The pendulum assembly adjustment method according to claim 9, characterized in that, The pendulum axis of the pendulum assembly is parallel to the bottom edge of the pressure loading frame; the adjustment fixture is placed on the cutting table of the laser cutting equipment; the laser is a picosecond laser or a femtosecond laser; when the laser adjustment pendulum assembly is oscillating at the center, it traverses the outer edge of the cutting center pendulum in a scribing manner.

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