Method for assembling and fixing quartz acceleration sensor

Abstract

The invention provides an assembling and fixing method of a quartz acceleration sensor, and the method comprises the steps: carrying out the test analysis and research of the working principle and working environment of each part in the quartz acceleration sensor, and the performance of various adhesives; in the assembling process of the magnetic steel assembly, the upper / lower torquer stator assembly, the meter core assembly, the meter head assembly and the whole meter assembly, 7-2312 modified epoxy structural adhesive, SY-53M elastic adhesive and DAD-91E conductive adhesive are used independently or in a combined mode according to the set positions and the adhesive coating thickness, and reliable bonding of all the assemblies is guaranteed; and the conductive requirements of each component are ensured, and the performance stability and the working reliability of the assembled quartz acceleration sensor are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial device assembly, and in particular relates to an assembly and fixing method of a quartz acceleration sensor. Background Art

[0002] The quartz accelerometer is installed on the three measuring axes of the strapdown inertial navigation subsystem to measure the linear acceleration of the vehicle on the three axes of the vehicle coordinate system. The output current of the accelerometer is proportional to the acceleration acting on the measuring axis, and the positive and negative signs of the output current are consistent with the direction of the acceleration.

[0003] Since the quartz accelerometer has a small size, a very compact internal structure, and many thin-walled parts, it is impossible to use the existing screw fixing method in aviation instruments. The solidification connection method between the parts of the traditional quartz accelerometer is to use the same adhesive for bonding and fixing. However, due to the different materials, usage requirements and usage environments of each part (high and low temperatures, vibration or impact, etc.), the creep of the adhesive between some parts is large, causing small displacements between the parts. If it exists in the bonding structure of key components such as differential capacitance sensors or push-pull permanent magnet torquers, it will affect the performance of the related products (long-term repeatability of bias and scale factor). Summary of the invention

[0004] In order to solve the problem that the existing quartz acceleration sensor has an unreliable assembly and fixation method for parts, the applicant has studied the working principles and use environment requirements of each component in the quartz acceleration sensor, and has conducted experimental analysis on the proportions and creep properties of various adhesives or adhesive combinations according to the working principles and use environment requirements of each component in the quartz acceleration sensor. Based on the analysis results, a method for assembling and fixing a quartz acceleration sensor is proposed, wherein the quartz acceleration sensor includes a housing, a first terminal assembly, a second terminal assembly, a lower torquer stator assembly, a magnetic steel assembly, a quartz pendulum, a torquer coil assembly, an upper torquer stator assembly, a belly band, an isolation ring, and a servo circuit. The assembly and fixation method includes the following steps:

[0005] Step 1: Assembling and fixing the magnetic steel assembly:

[0006] The magnetic steel and the magnetic cap are coaxially bonded to form a magnetic steel assembly by using DAD-91E conductive adhesive and 7-2312 modified epoxy structural adhesive, and a high-temperature curing treatment is performed; wherein the DAD-91E conductive adhesive is coated on the center of the bonding surface of the magnetic steel, and the remaining area of ​​the bonding surface is coated with 7-2312 modified epoxy structural adhesive, the adhesive layer thickness is 0.01mm to 0.02mm, and the adhesive layer thickness of the DAD-91E conductive adhesive is greater than the adhesive layer thickness of the 7-2312 modified epoxy structural adhesive;

[0007] Assembling to obtain a first magnetic steel assembly and a second magnetic steel assembly;

[0008] Step 2: Assemble and fix the upper torquer stator assembly and the first magnetic steel assembly:

[0009] Step 2.1, setting a plurality of first points on the cylindrical surface of the inner hole of the magnetic compensation ring of the upper torquer stator assembly, applying DAD-91E conductive glue on the first points, and applying 7-2312 modified epoxy structural glue on other areas of the cylindrical surface of the inner hole of the magnetic compensation ring, and the thickness of the adhesive layer of DAD-91E conductive glue is greater than the thickness of the adhesive layer of 7-2312 modified epoxy structural glue; embedding the first magnetic steel assembly in the inner hole of the magnetic compensation ring, bonding and fixing it flush with the end face of the inner hole, and forming a combination after high-temperature curing;

[0010] Step 2.2, apply DAD-91E conductive adhesive to the center of the bonding part of the bottom end surface of the yoke iron of the upper torquer stator assembly, and apply 7-2312 modified epoxy structural adhesive to the remaining area of ​​the bonding part, and the thickness of the DAD-91E conductive adhesive layer is greater than the thickness of the 7-2312 modified epoxy structural adhesive layer;

[0011] Step 2.3, using an existing special bonding fixture to coaxially embed the assembly formed by bonding the magnetic compensation ring and the first magnetic steel assembly in step 2.1 into the yoke of the upper torquer stator assembly, and perform high-temperature curing treatment together with the existing special bonding fixture;

[0012] Step 3: Assemble and fix the quartz pendulum assembly:

[0013] Use SY-53M elastic glue to coaxially bond and fix the two torquer coil assemblies to the center of both ends of the quartz pendulum to form a quartz pendulum assembly, and perform high-temperature curing treatment; SY-53M elastic glue must be prepared and used immediately, and the thickness of the SY-53M elastic glue layer is 0.03mm~0.06mm;

[0014] Step 4: Assemble and fix the lower torquer stator assembly with the first terminal assembly, the second terminal assembly and the second magnetic steel assembly:

[0015] Step 4.1, apply 7-2312 modified epoxy structural adhesive to the two terminal mounting holes on the yoke iron of the lower torquer stator assembly, respectively bond the first terminal assembly and the second terminal assembly to the corresponding terminal mounting holes, and after high-temperature curing, apply 7-2312 modified epoxy structural adhesive to the edges of the two end surfaces of the terminal mounting holes again and perform high-temperature curing treatment;

[0016] Step 4.2, setting a plurality of second points on the inner cylindrical surface of the magnetic compensation ring of the lower torquer stator assembly, applying DAD-91E conductive glue on the second points, applying 7-2312 modified epoxy structural glue on other areas of the inner cylindrical surface of the magnetic compensation ring, and the thickness of the adhesive layer of DAD-91E conductive glue is greater than the thickness of the adhesive layer of 7-2312 modified epoxy structural glue; embedding the second magnetic steel assembly in the inner hole of the magnetic compensation ring of the lower torquer stator assembly, bonding and fixing it flush with the end surface of the inner hole, and forming a combination after high-temperature curing;

[0017] Step 4.3, apply DAD-91E conductive adhesive to the center of the bonding part of the inner end surface of the yoke of the lower torquer stator assembly, and apply 7-2312 modified epoxy structural adhesive to the remaining bonding surface of the bonding part, and the thickness of the DAD-91E conductive adhesive layer is greater than the thickness of the 7-2312 modified epoxy structural adhesive layer;

[0018] Step 4.4, using an existing special bonding fixture to coaxially embed the assembly formed by bonding the magnetic compensation ring and the second magnetic steel assembly in step 4.2 into the yoke of the lower torquer stator assembly, and perform high-temperature curing treatment together with the special bonding fixture;

[0019] Step 5: Assemble and fix the movement components:

[0020] The watch core assembly is assembled by the lower torquer stator assembly, the quartz pendulum assembly, the upper torquer stator assembly and the belly band. The specific assembly and fixing process is as follows:

[0021] Step 5.1, use the existing special alignment and curing fixture to install the quartz pendulum assembly between the upper torquer stator assembly and the lower torquer stator assembly, and after qualified debugging, use a conductive plugging piece to plug the gap on the belly band;

[0022] Step 5.2, clamp the belly belt on the outer wall ring groove of the lower torquer stator assembly and the upper torquer stator assembly, perform high-temperature dehumidification treatment, and test the performance of the core assembly after returning to normal temperature until the performance is qualified;

[0023] Step 5.3, place the assembly of the upper torquer stator assembly, the quartz pendulum assembly and the lower torquer stator assembly horizontally, first apply 7-2312 modified epoxy structural adhesive along the joints between the two end surfaces of the belly band and the upper torquer stator assembly and the lower torquer stator assembly, and then perform high-temperature curing treatment after application; then remove the clamp, first apply DAD-91E conductive adhesive on the sealing piece in the belly band gap, and then apply HY-914 room temperature adhesive to seal the belly band gap after curing;

[0024] Step 5.4, place the assembled watch core assembly in a room temperature environment for curing and recovery, and after recovery, test the on-resistance between the upper torque device stator assembly and the lower torque device stator assembly in the watch core assembly. The on-resistance should be no greater than 2Ω. If it does not meet the requirement, fill the gap on the end face of the belly band gap with DAD-91E conductive glue;

[0025] Step 6: Assemble and fix the movement assembly, isolation ring and housing:

[0026] Step 6.1, using 7-2312 modified epoxy structural adhesive to bond and fix the inner cylindrical surface of the isolation ring to the upper outer cylindrical surface of the lower torque device stator assembly, and perform high temperature curing treatment;

[0027] Step 6.2, hoist the assembly of the meter core assembly and the isolation ring into the housing, and after the debugging and installation error angle is qualified, apply 7-2312 modified epoxy structural adhesive to the joint between the isolation ring and the housing for bonding to form the meter head assembly; perform high temperature curing according to the set time;

[0028] Step 7, assembly and fixation of the meter head assembly and servo circuit:

[0029] Step 7.1, solder the selected servo circuit and the meter head assembly with the corresponding color-coded installation wire according to the wiring requirements;

[0030] Step 7.2, evenly setting a plurality of third points on the inner cylindrical surface of the servo circuit mechanical interface, applying DAD-91E conductive adhesive on the third points, and applying 7-2312 modified epoxy structural adhesive on the remaining area of ​​the inner cylindrical surface of the mechanical interface, and the adhesive layer thickness of DAD-91E conductive adhesive is greater than the adhesive layer thickness of 7-2312 modified epoxy structural adhesive;

[0031] Step 7.3, coaxially install the servo circuit on the top of the shell, bond the inner cylindrical surface of the servo circuit mechanical interface to the outer cylindrical surface of the shell, and perform high-temperature curing treatment; after curing, check that the on-resistance of the servo circuit shell to the header assembly shell should be no more than 3Ω. If not, add DAD-91E conductive glue to the end face gap of the inner cylindrical surface of the servo circuit mechanical interface until the on-resistance meets the requirement;

[0032] Step 8: Perform air tightness test on the assembled quartz acceleration sensor. The air leakage rate should be no more than 5×10 - 9 Pa·m 3 / s, if the air leakage rate is unqualified, the glue is repaired and cured at the external joint of the quartz acceleration sensor or a sealing ring is installed for glue filling and sealing until the air leakage rate is qualified.

[0033] Furthermore, the step 1 comprises the following steps:

[0034] Step 1.1, apply DAD-91E conductive adhesive to the center of the bonding surface of the preheated magnetic steel, with the coating area accounting for 10% to 15% of the bonding surface, and apply 7-2312 modified epoxy structural adhesive to the remaining area of ​​the bonding surface;

[0035] Step 1.2, use the existing special adhesive fixture to coaxially bond the magnetic cap to the bonding surface of the magnetic steel, and the coaxiality requirement of the magnetic cap to the magnetic steel is ≤0.01mm;

[0036] Step 1.3, the bonded magnetic steel and magnetic cap are subjected to high temperature curing treatment together with the existing special bonding fixture, the high temperature curing temperature is 120°C, and the high temperature curing time is 2 hours.

[0037] Furthermore, in the step 1.2, when the magnetic cap and the magnetic steel are bonded by using the existing special bonding fixture, an axial pre-tightening force of 0.05MPa to 0.1MPa is applied for pre-tightening.

[0038] Furthermore, in the step 2.1, three first points are evenly set on the cylindrical surface of the inner hole of the magnetic compensation ring of the upper torquer stator assembly, and DAD-91E conductive glue is applied to the three set first points.

[0039] Furthermore, in step 2.2, the area of ​​DAD-91E conductive adhesive applied to the center of the inner end surface adhesive joint of the yoke of the upper torquer stator assembly is 10% to 15% of the inner end surface adhesive joint area of ​​the yoke, and the thickness of the adhesive layer is no more than 0.02 mm.

[0040] Furthermore, before performing step 3, the method further includes preparing SY-53M elastic glue: preparing the SY-53M elastic glue with a set component ratio, stirring the mixture evenly, and performing a vacuum treatment before use to ensure that there are no air bubbles in the glue solution.

[0041] Furthermore, in step 3, the two torquer coil assemblies are coaxially bonded and fixed to the two ends of the quartz pendulum using an existing special bonding fixture, and the pre-tightening force of the existing special bonding fixture during bonding is 0.05MPa to 0.1MPa.

[0042] Furthermore, in step 5.1, the conductive sealing member used is tin foil.

[0043] Furthermore, in step 6.2, after the assembly of the watch core assembly and the isolation ring is hoisted into the shell, the three-point balance method is used to debug the installation error angle. When the installation error angle meets the design requirements, 7-2312 modified epoxy structural adhesive is applied to the joint between the isolation ring and the shell. After curing for a set time, the installation error angle is checked again to see if it meets the design requirements. If not, the watch core assembly and the isolation ring are disassembled and reassembled until the installation error angle is qualified.

[0044] The advantages of the present invention are:

[0045] The quartz acceleration sensor assembly and fixing method provided by the present invention not only ensures the reliability of bonding between components, but also satisfies the electrical conductivity of some parts, so that the stability of the performance and working reliability of the assembled quartz acceleration sensor are guaranteed. The specific advantages are as follows:

[0046] 1. SY-53M elastic adhesive is used alone in the assembly of the quartz pendulum assembly to ensure that the moving piece of the differential capacitance sensor in the quartz pendulum assembly works stably and reliably, and the moving coil of the push-pull electromagnetic torquer works stably and reliably.

[0047] 2. In the assembly of the meter head assembly, structural epoxy adhesive 7-2312 is used alone for bonding, which not only solidifies the installation accuracy of the quartz accelerometer, but also ensures the sealing requirements of the quartz accelerometer.

[0048] 3. In the assembly of the meter core assembly and the upper / lower torque device stator assembly, 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive are used in combination for bonding, so that the ground of the differential capacitance sensor in the meter core assembly and the upper / lower torque device stator assembly, the ground of the push-pull permanent magnet torque device and the ground of the positive and negative power supplies are shared, and the electromagnetic interference generated by the quartz acceleration sensor during operation can be minimized, ensuring the stable and reliable operation of the differential capacitance sensor and the push-pull permanent magnet torque device from the source of structural design and electrical design.

[0049] 4. In the assembly of the upper / lower torquer and the belly belt in the watch core assembly, a combination of 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive is used for bonding, so that the upper / lower torquer and the belly belt in the watch core assembly are conductive, so that the watch core assembly forms an independent magnetic shielding system, ensuring that the inside of the watch core assembly does not generate electromagnetic interference to the outside, and also ensuring that the external electromagnetic interference source does not generate electromagnetic interference to the inside of the watch core assembly, ensuring the stable and reliable operation of the differential capacitance sensor and the push-pull permanent magnet torquer from the source of electrical design.

[0050] 5. In the assembly of the servo circuit housing and the housing in the meter head assembly, a combination of 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive is used for bonding, which not only makes the servo circuit housing and the housing in the meter head assembly conductive, but also forms an independent magnetic shielding system for the entire meter, ensuring that the inside of the meter does not generate electromagnetic interference to the outside, and the outside does not generate electromagnetic interference to the inside of the meter, ensuring the stable and reliable operation of the entire meter from the source of electrical design;

[0051] 6. Once the quartz acceleration sensor leaks, the air pressure film damping inside the watch movement will change under high, low temperature or high humidity conditions, causing the quartz acceleration sensor to oscillate when it is powered on. Therefore, the method of the present invention uses 7-2312 modified epoxy structural adhesive, DAD-91E conductive adhesive and HY914 adhesive in combination or alone, so that the quartz acceleration sensor has a triple sealing structure from the inside to the outside, one is the sealing of the watch movement assembly, the second is the sealing of the watch head assembly, and the third is the sealing of the entire watch, that is, the sealing of the servo circuit and the watch head assembly. This triple sealing structure ensures the airtightness of the entire watch, that is, the leakage rate is not greater than 5×10 -9 Pa·m 3 / s, ultimately ensuring that the quartz accelerometer works stably and reliably.

[0052] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0054] Figure 1 This is the appearance diagram of the quartz acceleration sensor;

[0055] Figure 2 This is an exploded diagram of a quartz accelerometer;

[0056] Figure 3 It is a schematic diagram of the structure of the magnetic steel component in the quartz acceleration sensor;

[0057] Figure 4 It is a schematic diagram of the structure of the quartz pendulum assembly in the quartz acceleration sensor;

[0058] Figure 5 It is a schematic diagram of the overall structure of the upper torquer stator assembly in the quartz acceleration sensor;

[0059] Figure 6 It is a cross-sectional view of the structure of the upper torquer stator assembly in the quartz acceleration sensor;

[0060] Figure 7 It is a schematic diagram of the three-dimensional structure of the core assembly of the quartz acceleration sensor;

[0061] Figure 8 It is a cross-sectional view of the movement assembly in the quartz acceleration sensor;

[0062] Fig. 9 It is a schematic diagram of the three-dimensional structure of the meter head assembly in the quartz acceleration sensor;

[0063] Fig.10It is a cross-sectional view of the structure of the header assembly in the quartz acceleration sensor;

[0064] Fig.11 This is a schematic diagram of the cooperation between the meter head assembly and the servo circuit in the quartz acceleration sensor;

[0065] Fig.12 The present invention is a flowchart of the quartz acceleration sensor assembly and fixing process.

[0066] In the figure: 1-housing, 2-upper torquer stator assembly, 201-upper magnetic compensation ring, 202-upper yoke, 3-magnetic steel assembly, 301-magnetic steel, 302-magnetic cap, 4-quartz pendulum assembly, 401-quartz pendulum, 402-torquer coil assembly, 5-lower torquer stator assembly, 6-belly belt, 7-isolating ring, 8-servo circuit, 9-tin foil, 10-first terminal assembly, 11-second terminal assembly. DETAILED DESCRIPTION

[0067] Embodiments of the present invention are described in detail below. The embodiments are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0068] Reference Figure 1 and Figure 2 A quartz acceleration sensor includes a shell 1, an upper torquer stator assembly 2, a magnetic steel assembly 3, a quartz pendulum assembly 4, a lower torquer stator assembly 5, a belly band 6, an isolation ring 7, a servo circuit 8, a first terminal assembly 10 and a second terminal assembly 11 in sequence.

[0069] Reference Fig.12 The embodiment of the present invention provides a method for assembling and fixing the acceleration sensor, comprising the following steps:

[0070] Step 1: Assembling and fixing the magnetic steel assembly:

[0071] like Figure 3 As shown, the magnetic steel assembly 3 includes a magnetic steel 301 and a magnetic cap 302. The magnetic steel 301 and the magnetic cap 302 need not only to be firmly bonded, but also have conductivity requirements, and the conductive resistance is ≤ 2Ω. Therefore, in the embodiment of the present invention, epoxy 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive are used in combination to assemble and fix the magnetic steel 301 and the magnetic cap 302. The specific assembly and fixing method is:

[0072] Step 1.1, take out the preheated magnetic steel 301 from the high temperature box, first apply DAD-91E conductive adhesive on the center of its bonding surface, 10% to 15% of the adhesive surface, and apply 7-2312 modified epoxy structural adhesive on the remaining bonding surface, the thickness of the adhesive layer is not more than 0.02mm, and the thickness of the DAD-91E conductive adhesive layer must be higher than the thickness of the 7-2312 modified epoxy structural adhesive layer;

[0073] Step 1.2, use the existing special adhesive fixture to coaxially bond the magnetic cap 302 to the bonding surface of the magnetic steel 301, and the coaxiality requirement (≤0.01mm) of the magnetic cap to the magnetic steel is guaranteed by the adhesive fixture; apply an axial preload of 0.05MPa to 0.1MPa during the bonding process;

[0074] Step 1.3, put the assembled magnetic steel and magnetic cap together with the adhesive fixture into a high temperature box for curing. The high temperature curing temperature is 120°C and the high temperature curing time is 2 hours.

[0075] The embodiment of the present invention uses a combination of 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive to assemble and fix the magnetic steel and the magnetic cap, which not only ensures the firmness of the magnetic steel assembly, but also ensures the conductive performance between the magnetic steel and the magnetic cap.

[0076] Two magnetic steel components are assembled in the above manner.

[0077] Step 2: Assemble and fix the upper torquer stator assembly to one of the magnetic steel assemblies:

[0078] Reference Figure 5 and Figure 6 The upper torquer stator assembly 2 includes an upper magnetic compensation ring 201 and an upper yoke 202. The assembly and fixing process of the upper torquer stator assembly 2 and a magnetic steel assembly is as follows:

[0079] Step 2.1, three points are evenly set on the inner cylindrical surface of the upper magnetic compensation ring 201, DAD-91E conductive adhesive is applied to the three points, and 7-2312 modified epoxy structural adhesive is applied to the remaining surface of the inner cylindrical surface of the upper magnetic compensation ring 201, and the thickness of the adhesive layer is not more than 0.02 mm, and the thickness of the DAD-91E conductive adhesive layer is higher than the thickness of the 7-2312 modified epoxy structural adhesive layer;

[0080] A magnetic steel component 3 is embedded in the inner hole of the upper magnetic compensation ring 201, and the end surface of the magnetic steel 301 is in contact with the end surface of the inner hole of the upper magnetic compensation ring 201.

[0081] Step 2.2, first apply DAD-91E conductive adhesive to the center of the bonding part of the bottom end surface of the upper yoke 202, and apply 10% to 15% of the adhesive surface, and apply 7-2312 modified epoxy structural adhesive to the remaining bonding surfaces of the bonding part, the thickness of the adhesive layer is not more than 0.02mm, and the thickness of the DAD-91E adhesive layer must be greater than the thickness of the 7-2312 modified epoxy structural adhesive;

[0082] Step 2.3, using an existing special bonding fixture to implant the combination of the upper magnetic compensation ring 201 and the magnetic steel assembly 3 into the upper yoke 202, and applying an axial preload of 0.05MPa to 0.1MPa;

[0083] Step 2.4, put the combination of the magnetic steel assembly and the upper torquer stator assembly 2 into a high temperature box together with the bonding fixture for curing. It should be noted that when applying DAD-91E conductive glue, the coating thickness and number of points of the conductive glue should ensure that the conductive resistance between the upper magnetic compensation ring 201 and the magnetic steel 301, and between the magnetic cap 302 and the upper yoke 202 is ≤2Ω.

[0084] Step 3, assembling and fixing the quartz pendulum assembly 4:

[0085] like Figure 4 As shown, the quartz pendulum assembly 4 is assembled from a quartz pendulum 401 and a torquer coil assembly 402. Since the quartz pendulum is made of quartz glass and the skeleton of the torquer coil assembly 402 is made of hard aluminum, structural epoxy adhesive is not suitable for bonding between metal materials and quartz glass, because the temperature coefficients of the two are very different under high and low temperature conditions. Under the action of thermal expansion and contraction, the structural epoxy adhesive will cause the quartz glass bonded to the aluminum skeleton to separate from the quartz glass substrate and eventually cause the entire acceleration sensor to lose its function and fail to work. Therefore, it is particularly important to ensure reliable fixation between the skeleton of the torquer coil assembly and the quartz pendulum. The embodiment of the present invention uses SY-53M elastic adhesive for bonding, and the adhesive must be prepared and used immediately. The assembly and fixing process of the skeleton of the torquer coil assembly and the quartz pendulum includes the following steps:

[0086] Step 3.1, prepare SY-53M elastic glue according to the set component ratio, stir it evenly, and evacuate it before use to ensure that there are no air bubbles in the glue;

[0087] In step 3.2, the SY-53M elastic glue prepared in step 2.1 is used, and the two torquer coil assemblies are coaxially bonded and fixed to the center parts of both ends of the quartz pendulum through the existing bonding fixture, and the thickness of the glue layer is 0.03mm to 0.06mm; during the bonding process, the bonding fixture is used to ensure that the coaxiality of the quartz pendulum assembly and the torquer coil assembly 402 installed at both ends thereof is ≤0.01mm.

[0088] Step 3.3, setting the preload force of the existing special bonding fixture to 0.05MPa-0.1Mpa; placing the quartz pendulum assembly together with the bonding fixture into a high temperature box for heating and curing.

[0089] Step 4, refer to Figure 6 and Figure 7 The lower torquer stator assembly is composed of the same components as the upper torquer stator assembly, including a magnetic compensation ring and a yoke. The assembly and fixing process of the lower torquer stator assembly with the first terminal assembly 10, the second terminal assembly 11 and another magnetic steel assembly is as follows:

[0090] Step 4.1, apply 7-2312 modified epoxy structural adhesive to the two terminal mounting holes on the yoke iron of the lower torquer stator assembly, respectively bond the first terminal assembly and the second terminal assembly to the corresponding terminal mounting holes, and after high-temperature curing, apply 7-2312 modified epoxy structural adhesive to the edges of the two end surfaces of the terminal mounting holes again and perform high-temperature curing treatment;

[0091] Step 4.2, set multiple points (three points in the implementation of the present invention) on the inner hole cylindrical surface of the magnetic compensation ring of the lower torquer stator assembly, apply DAD-91E conductive glue on the set points, and apply 7-2312 modified epoxy structural glue on other areas of the inner hole cylindrical surface of the magnetic compensation ring, the glue layer thickness is not more than 0.02mm and the glue layer thickness of DAD-91E conductive glue is greater than the glue layer thickness of 7-2312 modified epoxy structural glue; embed the assembled other magnetic steel assembly into the inner hole of the magnetic compensation ring of the lower torquer stator assembly, and fix it flush with the end surface of the inner hole, and form a combination after high-temperature curing;

[0092] Step 4.3, apply DAD-91E conductive adhesive to the center of the bonding part of the inner bottom end surface of the yoke of the lower torquer stator assembly, and apply 7-2312 modified epoxy structural adhesive to the remaining bonding surface of the bonding part, the thickness of the adhesive layer is not more than 0.02mm, and the thickness of the DAD-91E conductive adhesive layer is greater than the thickness of the 7-2312 modified epoxy structural adhesive layer;

[0093] Step 4.4, use the existing special bonding fixture to coaxially embed the combination formed by bonding the magnetic compensation ring and the magnetic steel assembly in step 4.2 into the yoke of the lower torquer stator assembly. During the embedding process, the existing special bonding fixture applies an axial preload force of 0.05MPa to 0.1Mpa; then put the assembly of the lower torquer stator assembly and the magnetic steel assembly into a drying oven together with the special bonding fixture for high-temperature curing treatment.

[0094] It should be noted that when applying DAD-91E conductive adhesive, the coating thickness and number of points of the conductive adhesive should ensure that the conductive resistance between the magnetic compensation ring and the magnetic steel of the lower torquer stator assembly, and between the magnetic cap and the upper yoke of the lower torquer stator assembly is ≤2Ω.

[0095] Step 5: Assemble and fix the movement components:

[0096] Refer to 7 and Figure 8 The watch core assembly is assembled by the upper torquer stator assembly 2, the quartz pendulum assembly 4, the lower torquer stator assembly 5 and the belly band 6. The specific assembly and fixing process is as follows:

[0097] Step 5.1, use the existing special alignment and curing fixture to install the quartz pendulum assembly between the upper torquer stator assembly and the lower torquer stator assembly, and after the debugging is qualified, use a conductive plugging piece to plug the gap on the belly band. In this embodiment, tin foil is used to plug the gap of the belly band 6.

[0098] Step 5.2, clamp the belly belt on the outer wall ring groove of the lower torque device stator assembly and the upper torque device stator assembly, perform high-temperature dehumidification treatment, and test the performance of the assembly after returning to normal temperature until the performance is qualified;

[0099] Step 5.3, place the assembly of the upper torquer stator assembly, the quartz pendulum assembly and the lower torquer stator assembly horizontally, apply a circle of 7-2312 modified epoxy structural adhesive along the joints between the two end surfaces of the belly band and the upper torquer stator assembly and the lower torquer stator assembly, and invert the assembly in a drying oven for high-temperature curing; then remove the sealing parts, apply DAD-91E conductive adhesive in the gap of the belly band, and after curing, apply HY-914 room temperature adhesive to seal the gap of the belly band.

[0100] Step 5.4, place the assembled watch core assembly in a room temperature environment for curing and recovery. After recovery, test the on-resistance between the upper torque device stator assembly and the lower torque device stator assembly in the watch core assembly. The on-resistance should be no greater than 2Ω. If it does not meet the requirement, fill the gap on the end face of the belly band notch with DAD-91E conductive glue.

[0101] Step 6: Assembling and fixing the watch movement assembly, the isolation ring 7 and the housing 1:

[0102] Reference Fig. 9 and Fig.10 The housing 1, the watch core assembly and the isolation ring 7 are assembled to form the watch head assembly. The specific assembly and fixing process is as follows:

[0103] Step 6.1, apply 7-2312 modified epoxy structural adhesive on the inner cylindrical surface of the isolation ring 7, and nest the isolation ring 7 on the corresponding outer cylindrical surface of the lower torque device stator assembly 5, and the lower end surface of the isolation ring 7 is in contact with the step surface of the lower torque device stator assembly 5; after bonding, clean up the remaining adhesive and perform high-temperature curing;

[0104] Step 6.2, use the existing special lifting fixture to lift the watch movement assembly in the shell 1 and use the three-point leveling method to debug the installation error angle. After the installation error angle is qualified, apply 7-2312 modified epoxy structural adhesive to the peripheral gap between the isolation ring 7 and the shell 1, put the assembly together with the lifting fixture into the drying oven for curing for 40 minutes, take it out of the drying oven and re-test the installation error angle. If it is qualified, the glue seal should be repaired and no bubbles are generated before high-temperature curing.

[0105] Three-point balancing method: Use hanging screws to suspend the watch movement assembly in the shell, and use three set screws on the periphery to support the upper end surface of the watch movement assembly, and debug based on the principle that three points determine a plane.

[0106] Step 7, assembly and fixation of the meter head assembly and servo circuit:

[0107] Step 7.1, solder the selected servo circuit and the meter head assembly with the corresponding color-coded installation wire according to the wiring requirements; the conduction resistance of the servo circuit housing to the meter head assembly housing is not greater than 3Ω.

[0108] Step 7.2, set 4 points on the inner cylindrical surface of the mechanical interface of the servo circuit 8, evenly apply DAD-91E conductive adhesive on the points, and apply 7-2312 modified epoxy structural adhesive on the remaining area of ​​the inner cylindrical surface of the mechanical interface, and the thickness of the conductive adhesive layer is higher than the thickness of the adhesive layer of 7-2312 modified epoxy structural adhesive.

[0109] Step 7.3, use the existing special bonding fixture to install the servo circuit on the top of the housing 1 according to the required assembly position, so that the inner cylindrical surface of the servo circuit mechanical interface is bonded to the outer cylindrical surface of the housing; clean up the remaining glue after bonding. Fig.11 shown.

[0110] Put the combination of the meter head assembly and the servo circuit together with the bonding fixture into a high temperature box for curing. After curing, check that the on-resistance of the servo circuit housing to the meter head assembly housing should be no more than 3Ω. If it does not meet the requirement, add DAD-91E conductive glue to the end face gap of the inner cylindrical surface of the servo circuit mechanical interface until the on-resistance meets the requirement.

[0111] Step 8: Perform air tightness test on the assembled quartz acceleration sensor. The air leakage rate should be no more than 5×10 - 9 Pa·m 3 / s, if the air leakage rate is unqualified, the glue is repaired and cured at the external joint of the quartz acceleration sensor or a sealing ring is installed for glue filling and sealing until the air leakage rate is qualified.

[0112] In summary, in the assembly process of the first terminal assembly, the second terminal assembly, the magnetic steel assembly, the upper / lower torquer stator assembly, the quartz pendulum, the torquer coil assembly, the isolation ring and the servo circuit, 7-2312 modified epoxy structural adhesive and SY-53M elastic adhesive are used alone, and 7-2312 modified epoxy structural adhesive and DAD-91E conductive adhesive are used in combination. Whether used alone or in combination, the advantages are significant, which not only ensures the bonding reliability of the assembly, but also meets the special performance of specific components with electrical conductivity requirements, and finally effectively guarantees the performance stability and working reliability of the quartz acceleration sensor.

[0113] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A method for assembling and fixing a quartz acceleration sensor, the quartz acceleration sensor comprising a housing, a first terminal assembly, a second terminal assembly, a lower torquer stator assembly, a magnetic steel assembly, a quartz pendulum, a torquer coil assembly, an upper torquer stator assembly, a belly band, an isolation ring and a servo circuit, characterized in that: The assembly and fixing method comprises the following steps: Step 1: Assembling and fixing the magnetic steel assembly: The magnetic steel and the magnetic cap are coaxially bonded to form a magnetic steel assembly by using DAD-91E conductive adhesive and 7-2312 modified epoxy structural adhesive, and a high-temperature curing treatment is performed; wherein the DAD-91E conductive adhesive is coated on the center of the bonding surface of the magnetic steel, and the remaining area of ​​the bonding surface is coated with 7-2312 modified epoxy structural adhesive, the adhesive layer thickness is 0.01mm to 0.02mm, and the adhesive layer thickness of the DAD-91E conductive adhesive is greater than the adhesive layer thickness of the 7-2312 modified epoxy structural adhesive; Assembling to obtain a first magnetic steel assembly and a second magnetic steel assembly; Step 2: Assemble and fix the upper torquer stator assembly and the first magnetic steel assembly: Step 2.1, setting a plurality of first points on the cylindrical surface of the inner hole of the magnetic compensation ring of the upper torquer stator assembly, applying DAD-91E conductive glue on the first points, and applying 7-2312 modified epoxy structural glue on other areas of the cylindrical surface of the inner hole of the magnetic compensation ring, and the thickness of the adhesive layer of DAD-91E conductive glue is greater than the thickness of the adhesive layer of 7-2312 modified epoxy structural glue; embedding the first magnetic steel assembly in the inner hole of the magnetic compensation ring, bonding and fixing it flush with the end face of the inner hole, and forming a combination after high-temperature curing; Step 2.2, apply DAD-91E conductive adhesive to the center of the bonding part of the bottom end surface of the yoke iron of the upper torquer stator assembly, and apply 7-2312 modified epoxy structural adhesive to the remaining area of ​​the bonding part, and the thickness of the DAD-91E conductive adhesive layer is greater than the thickness of the 7-2312 modified epoxy structural adhesive layer; Step 2.3, using an existing special bonding fixture to coaxially embed the assembly formed by bonding the magnetic compensation ring and the first magnetic steel assembly in step 2.1 into the yoke of the upper torquer stator assembly, and perform high-temperature curing treatment together with the existing special bonding fixture; Step 3: Assemble and fix the quartz pendulum assembly: Use SY-53M elastic glue to coaxially bond and fix the two torquer coil assemblies to the center of both ends of the quartz pendulum to form a quartz pendulum assembly, and perform high-temperature curing treatment; SY-53M elastic glue must be prepared and used immediately, and the thickness of the SY-53M elastic glue layer is 0.03mm~0.06mm; Step 4: Assemble and fix the lower torquer stator assembly with the first terminal assembly, the second terminal assembly and the second magnetic steel assembly: Step 4.1, apply 7-2312 modified epoxy structural adhesive to the two terminal mounting holes on the yoke iron of the lower torquer stator assembly, respectively bond the first terminal assembly and the second terminal assembly to the corresponding terminal mounting holes, and after high-temperature curing, apply 7-2312 modified epoxy structural adhesive to the edges of the two end surfaces of the terminal mounting holes again and perform high-temperature curing treatment; Step 4.2, setting a plurality of second points on the inner cylindrical surface of the magnetic compensation ring of the lower torquer stator assembly, applying DAD-91E conductive glue on the second points, and applying 7-2312 modified epoxy structural glue on other areas of the inner cylindrical surface of the magnetic compensation ring, and the thickness of the adhesive layer of DAD-91E conductive glue is greater than the thickness of the adhesive layer of 7-2312 modified epoxy structural glue; embedding the second magnetic steel assembly in the inner hole of the magnetic compensation ring of the lower torquer stator assembly, bonding and fixing it flush with the end surface of the inner hole, and forming a combination after high-temperature curing; Step 4.3, apply DAD-91E conductive adhesive to the center of the bonding part of the inner bottom end surface of the yoke of the lower torquer stator assembly, and apply 7-2312 modified epoxy structural adhesive to the remaining bonding surface of the bonding part, and the thickness of the DAD-91E conductive adhesive layer is greater than the thickness of the 7-2312 modified epoxy structural adhesive layer; Step 4.4, using an existing special bonding fixture to coaxially embed the assembly formed by bonding the magnetic compensation ring and the second magnetic steel assembly in step 4.2 into the yoke of the lower torquer stator assembly, and perform high-temperature curing treatment together with the special bonding fixture; Step 5: Assemble and fix the movement components: The watch core assembly is assembled by the lower torquer stator assembly, the quartz pendulum assembly, the upper torquer stator assembly and the belly band. The specific assembly and fixing process is as follows: Step 5.1, use the existing special alignment and curing fixture to install the quartz pendulum assembly between the upper torquer stator assembly and the lower torquer stator assembly, and after qualified debugging, use a conductive plugging piece to plug the gap on the belly band; Step 5.2, clamp the belly belt on the outer wall ring groove of the lower torquer stator assembly and the upper torquer stator assembly, perform high-temperature dehumidification treatment, and test the performance of the core assembly after returning to normal temperature until the performance is qualified; Step 5.3, place the assembly of the upper torquer stator assembly, the quartz pendulum assembly and the lower torquer stator assembly horizontally, first apply 7-2312 modified epoxy structural adhesive along the joints between the two end surfaces of the belly band and the upper torquer stator assembly and the lower torquer stator assembly, and then perform high-temperature curing after application; then remove the clamp, first apply DAD-91E conductive adhesive on the sealing piece in the belly band gap, and then apply HY-914 room temperature adhesive to seal the belly band gap after curing; Step 5.4, place the assembled watch core assembly in a room temperature environment for curing and recovery, and after recovery, test the on-resistance between the upper torque device stator assembly and the lower torque device stator assembly in the watch core assembly. The on-resistance should be no greater than 2Ω. If it does not meet the requirement, fill the gap on the end face of the belly band gap with DAD-91E conductive glue; Step 6: Assemble and fix the movement assembly, isolation ring and housing: Step 6.1, using 7-2312 modified epoxy structural adhesive to bond and fix the inner cylindrical surface of the isolation ring to the upper outer cylindrical surface of the lower torque device stator assembly, and perform high temperature curing treatment; Step 6.2, hoist the assembly of the meter core assembly and the isolation ring into the housing, and after the debugging and installation error angle is qualified, apply 7-2312 modified epoxy structural adhesive to the joint between the isolation ring and the housing for bonding to form the meter head assembly; perform high temperature curing according to the set time; Step 7, assembly and fixation of the meter head assembly and servo circuit: Step 7.1, solder the selected servo circuit and the meter head assembly with the corresponding color-coded installation wire according to the wiring requirements; Step 7.2, evenly setting a plurality of third points on the inner cylindrical surface of the servo circuit mechanical interface, applying DAD-91E conductive adhesive on the third points, and applying 7-2312 modified epoxy structural adhesive on the remaining area of ​​the inner cylindrical surface of the mechanical interface, and the adhesive layer thickness of DAD-91E conductive adhesive is greater than the adhesive layer thickness of 7-2312 modified epoxy structural adhesive; Step 7.3, coaxially install the servo circuit on the top of the shell, bond the inner cylindrical surface of the servo circuit mechanical interface to the outer cylindrical surface of the shell, and perform high-temperature curing treatment; after curing, check that the on-resistance of the servo circuit shell to the header assembly shell should be no more than 3Ω. If not, add DAD-91E conductive glue to the end face gap of the inner cylindrical surface of the servo circuit mechanical interface until the on-resistance meets the requirement; Step 8: Perform air tightness test on the assembled quartz acceleration sensor. The air leakage rate should be no more than 5×10 -9 Pa·m 3 / s, if the air leakage rate is unqualified, the glue is repaired and cured at the external joint of the quartz acceleration sensor or a sealing ring is installed for glue filling and sealing until the air leakage rate is qualified.

2. The method for assembling and fixing a quartz acceleration sensor according to claim 1, characterized in that: The step 1 comprises the following steps: Step 1.1, apply DAD-91E conductive adhesive to the center of the bonding surface of the preheated magnetic steel, with the coating area accounting for 10% to 15% of the bonding surface, and apply 7-2312 modified epoxy structural adhesive to the remaining area of ​​the bonding surface; Step 1.2, use the existing special adhesive fixture to coaxially bond the magnetic cap to the bonding surface of the magnetic steel, and the coaxiality requirement of the magnetic cap to the magnetic steel is ≤0.01mm; Step 1.3, the bonded magnetic steel and magnetic cap are subjected to high temperature curing treatment together with the existing special bonding fixture, the high temperature curing temperature is 120°C, and the high temperature curing time is 2 hours.

3. The method for assembling and fixing a quartz acceleration sensor according to claim 2, characterized in that: In the step 1.2, when the magnetic cap and the magnetic steel are bonded by the existing special bonding fixture, an axial pre-tightening force of 0.05MPa to 0.1MPa is applied for pre-tightening.

4. The method for assembling and fixing a quartz acceleration sensor according to claim 1, characterized in that: In the step 2.1, three first points are evenly set on the cylindrical surface of the inner hole of the magnetic compensation ring of the upper torquer stator assembly, and DAD-91E conductive glue is applied to the three set first points.

5. The method for assembling and fixing a quartz acceleration sensor according to claim 4, characterized in that: In step 2.2, the area of ​​DAD-91E conductive adhesive applied to the center of the inner end surface adhesive joint of the yoke of the upper torquer stator assembly is 10% to 15% of the inner end surface adhesive joint area of ​​the yoke, and the thickness of the adhesive layer is no more than 0.02 mm.

6. The method for assembling and fixing a quartz acceleration sensor according to claim 1, characterized in that: Before step 3, the method further includes preparing SY-53M elastic glue: preparing the SY-53M elastic glue according to the set component ratio, stirring it evenly, and vacuuming it before use to ensure that there are no air bubbles in the glue solution.

7. The method for assembling and fixing a quartz acceleration sensor according to claim 6, characterized in that: In the step 3, the two torquer coil assemblies are coaxially bonded and fixed to the two ends of the quartz pendulum using an existing special bonding fixture, and the pre-tightening force of the existing special bonding fixture during bonding is 0.05MPa to 0.1MPa.

8. The method for assembling and fixing a quartz acceleration sensor according to claim 1, characterized in that: In the step 5.1, the conductive sealing member used is tin foil.

9. The method for assembling and fixing a quartz acceleration sensor according to claim 1, characterized in that: In step 6.2, after the assembly of the watch core assembly and the isolation ring is hoisted into the housing, the three-point balance method is used to debug the installation error angle. When the installation error angle meets the design requirements, 7-2312 modified epoxy structural adhesive is applied to the joint between the isolation ring and the housing. After curing for the set time, the installation error angle is checked again to see if it meets the design requirements. If not, the watch core assembly and the isolation ring are disassembled and reassembled until the installation error angle is qualified.

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