A hemispherical resonant gyroscope indium welding device and process method based on temperature gradient

Abstract

The present invention discloses an indium welding device and process method for a hemispherical resonator gyroscope based on a temperature gradient, and belongs to the technical field of indium welding assembly of a hemispherical resonator gyroscope. The indium welding process method of the present invention comprises the following steps: 1. According to the size of the resonator and the electrode base, an indium sheet of corresponding thickness and height is rolled; 2. The electrode base is fixed, and the rolled cylindrical indium sheet is prefabricated on the center rod of the resonator or the center hole of the base, and the resonator is fixed; 3. The detection device detects the posture of the resonator and the electrode base, and performs the axial hole alignment assembly; 4. The heating equipment is powered on for heating, and there is a temperature gradient in the height direction of the cylindrical indium sheet, the lower end melts first, and the unmelted indium sheet at the upper end gradually slides down and melts, and finally fills the assembly gap; 5. After the indium sheet is completely melted, the heating is stopped, and the indium welding is completed after the indium cools and solidifies. The present invention solves the problem that the existing welding method cannot completely, densely and evenly fill the assembly gap.

Description

Technical Field

[0001] The invention relates to the technical field of indium welding assembly of a hemispherical resonator gyroscope, and in particular to an indium welding device and a process method for a hemispherical resonator gyroscope based on a temperature gradient. Background Art

[0002] A hemispherical resonator gyroscope is an inertial navigation element based on the Coriolis effect. The resonator and electrode base are key components of the hemispherical resonator gyroscope. The two are connected by high-purity indium. The quality of the connection affects the performance, accuracy, and life of the gyroscope. Therefore, it is very important to study the indium welding connection equipment and indium welding process of the resonator and electrode base.

[0003] At present, the research on the assembly process of hemispherical resonator gyroscopes is mainly focused on assembly detection methods, assembly parameter identification, and the development of assembly and adjustment equipment, but there is no research on the indium soldering connection process for the resonator and the electrode base. At present, among the published patents, ZL202210252949.5 studies the electrode substrate fixing device for welding the resonator to the electrode substrate. The study first applies viscous slurry solder on the center rod of the resonator and the center hole of the base before assembly. ZL202111018486.8 studies the welding method for the resonator and the base of the quartz hemispherical resonator gyroscope. After the rough assembly of the resonator and the electrode base is completed, the tin-silver-copper solder sheet is inserted into the gap between the two, and the solder sheet is heated as a whole using electromagnetic induction heating.

[0004] Therefore, there are still some deficiencies and gaps in the existing research on the indium welding connection between the resonator and the electrode base:

[0005] 1. The process of applying viscous slurry solder is difficult to balance the volume of applied solder and the difficulty of assembly, it is difficult to completely fill the assembly gap, and the solder may be partially solidified before the resonator and the electrode base are assembled.

[0006] 2. The process method of inserting tin-silver-copper solder sheets after rough assembly does not consider the relationship between the volume of the inserted solder sheet and the volume of the assembly gap, does not achieve complete filling of the assembly gap between the resonator and the electrode base, and the process method has high requirements on the fluidity of the molten solder.

[0007] 3. There is no method for welding the resonator and electrode base for high-purity indium. Indium has a low melting point, and molten indium has good spreading and flow properties on the gold-plated surface of the resonator and electrode base, making it an excellent choice for soldering the resonator and electrode base. Summary of the invention

[0008] In view of this, the present invention provides a hemispherical resonator gyroscope indium welding device and process method based on temperature gradient, which can effectively complete the indium welding process of the resonator and the electrode base, solve the problem that the assembly gap between the resonator and the electrode base cannot be completely, densely and evenly filled, has strong adaptability to assembly environment and assembly size, and provides a technical basis for improving the performance and accuracy of the hemispherical resonator gyroscope.

[0009] A temperature gradient-based indium welding device for a hemispherical resonant gyroscope comprises a gantry, a six-axis precision displacement stage, a non-destructive fixture, a fixture, a heating device, an optical platform and a cylindrical indium sheet, wherein the indium welding objects are a resonator and an electrode base;

[0010] The gantry and the fixture are fixed on the optical platform, the six-axis precision translation stage is fixed on the crossbeam of the gantry, and the resonator is fixed on the six-axis precision translation stage by a non-destructive fixture; the heating device is placed on the optical platform and is located directly below the six-axis precision translation stage, and the electrode base is fixed on the upper surface of the heating device by a fixture; the cylindrical indium sheet is pre-set on the center rod of the resonator or the center hole of the electrode base before the resonator and the electrode base are assembled.

[0011] Furthermore, the indium soldering device also includes a detection device, which is used to detect the posture of the resonator and the electrode base to ensure that the resonator and the electrode base are in an ideal assembly posture, and the detection device uses a capacitive detection device or a spectral confocal sensor. The adjustment of the ideal assembly posture includes two steps. The first step is to adjust the resonator and the electrode base to be coaxial and horizontal, and the second step is to adjust the Z posture, which is to adjust the resonator and the electrode base to a specified gap.

[0012] Furthermore, the clamping force of the non-destructive clamp is adjustable.

[0013] A method for indium welding of a hemispherical resonant gyroscope based on a temperature gradient comprises the following steps:

[0014] Step 1: According to the size and assembly gap of the resonator and the electrode base, a cylindrical indium sheet of corresponding thickness and height is rolled;

[0015] Step 2, pre-place the cylindrical indium sheet on the central rod of the resonator or the central hole of the electrode base, and fix the resonator with a non-destructive clamp;

[0016] Step 3: After the detection device detects the postures of the resonator and the electrode base, the six-axis precision translation stage is used to adjust the postures of the resonator in the horizontal and rotational directions. After the specified parameter requirements are met, the posture of the resonator in the Z direction (the Z direction is the direction perpendicular to the horizontal plane) is adjusted to align the shaft holes of the resonator and the electrode base;

[0017] Step 4: The resonator, the electrode base and the bottom of the cylindrical indium sheet are heated by a heating device. During the heating process, there is a temperature gradient in the height direction of the indium sheet. The indium at the lower end that reaches the melting point first melts first, and the unmelted indium sheet at the upper end slides downward under the action of gravity and the pulling force of the molten pool at the lower end and gradually melts to fill the assembly gap;

[0018] Step 5: After the cylindrical indium sheet is completely melted, the heating device is turned off, and after the indium is cooled and solidified, the indium welding assembly of the resonator and the electrode base is completed.

[0019] Furthermore, the height of the cylindrical indium sheet in step 1 is calculated based on the assembly gap between the resonator and the electrode base and the thickness of the indium sheet.

[0020] Furthermore, before assembling the resonator and the electrode base in step 2, a pre-tightening force is applied to the lower end of the cylindrical indium sheet to fix it on the central rod of the resonator, or the cylindrical indium sheet is freely placed in the central hole of the electrode base.

[0021] Furthermore, the hemispherical resonant gyroscope indium welding process method is applied in a vacuum environment or a normal pressure environment.

[0022] Beneficial effects:

[0023] 1. The indium soldering device of the present invention fixes the resonator on a six-axis precision displacement table through a non-destructive clamp, and the electrode base is fixed on the upper surface of the heating device through a clamp. The cylindrical indium sheet is pre-set on the center rod of the resonator or the center hole of the electrode base before the assembly of the resonator and the electrode base, which can achieve complete filling and partial filling of the assembly gap without increasing the difficulty of assembly. Before the assembly of the resonator and the electrode base, all the solder is not placed in the assembly gap, which solves the contradiction between the volume of the prefabricated solder and the difficulty of assembly, and can achieve complete filling of the assembly gap with solder without increasing the difficulty of assembly. The degree of filling of the assembly gap can be adjusted by changing the height of the rolled indium sheet as required.

[0024] 2. The indium welding process of the present invention utilizes the temperature difference in the height direction of the indium sheet caused by the temperature gradient, introduces gravity and molten pool tension, and further improves the density and uniformity of welding. The high-purity indium used in the solder has a low melting point of 156.51°C, which is easy to assemble and can reduce the impact of welding heating on the resonator and the electrode base. At the same time, the characteristics of strong spreading and fluidity of indium and the coated gold layer are utilized, and the gravity of the unmelted indium sheet at the upper end and the tension of the indium molten pool at the lower end are introduced, which improves the density and uniformity of welding of the resonator and the electrode base.

[0025] 3. The indium welding process of the present invention has strong applicability. It can be used in vacuum environments with different vacuum degrees as well as in normal pressure environments. By selecting an indium sheet of appropriate thickness, it can be applied to resonators and electrode bases with different assembly gaps. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural diagram of the indium welding device of the hemispherical resonant gyroscope of the present invention;

[0027] Figure 2 It is a flow chart of the indium welding process of the hemispherical resonant gyroscope of the present invention;

[0028] Figure 3 It is a schematic diagram of assembling the rolled indium sheet before indium welding of the hemispherical resonator gyroscope of the present invention.

[0029] Among them, 1-gantry, 2-six-axis precision translation stage, 3-non-destructive fixture, 4-resonator, 5-electrode base, 6-fixture, 7-heating equipment, 8-optical platform. DETAILED DESCRIPTION

[0030] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0031] The present invention provides a hemispherical resonant gyro indium welding device based on temperature gradient, as shown in the attached Figure 1 As shown, the indium welding device includes a gantry 1, a six-axis precision translation stage 2, a non-destructive fixture 3, a fixture 6, a heating device 7, an optical platform 8, a cylindrical indium sheet and a detection device, and the indium welding objects are a resonator 4 and an electrode base 5.

[0032] The gantry 1 and the fixture 6 are fixed on the optical platform, the six-axis precision translation stage 2 is fixed on the crossbeam of the gantry 1, the resonator 4 is fixed on the six-axis precision translation stage 2 through the non-destructive fixture 3, the heating device 7 is placed on the optical platform 8, the electrode base 5 is fixed above the heating device 7 through the fixture 6, and the cylindrical indium sheet is pre-set on the center rod of the resonator or the center hole of the electrode base 5 before the resonator 4 and the electrode base 5 are assembled.

[0033] The resonator 4 is made of quartz glass, and its surface is evenly coated. A non-destructive clamp 3 is used to reduce the damage to the resonator 4 caused by clamping. At the same time, the clamping force of the non-destructive clamp 3 is adjustable. The clamping methods that can be used include adsorption clamps and mechanical clamps.

[0034] The clamp 6 is of V-shaped chuck type, one end of the clamp 6 is fixed and the other end is movable, and the movable end cooperates with the fixed end under the drive of the control system to hold the electrode base 5 tightly.

[0035] The heating device 7 adopts a heating platform or a heating plate, and its size should not affect the operation of the detection device.

[0036] The detection device may adopt capacitance detection, spectral confocal sensor, etc., which is not the content of the present invention and will not be described in detail here.

[0037] The process flow of the indium welding process of the hemispherical resonant gyroscope based on the temperature gradient of the present invention is as shown in the attached figure. Figure 2As shown, the specific steps include:

[0038] Step 1: According to the size and assembly gap of the center rod of the resonator and the center hole of the base, select an indium sheet of appropriate thickness to reduce the difficulty of subsequent assembly of the resonator and the electrode base, and determine the height h of the rolled cylindrical indium sheet according to the assembly gap and the thickness of the indium sheet:

[0039]

[0040] Wherein, D is the diameter of the center hole of the electrode base, d is the diameter of the center rod of the resonator, H is the assembly gap height, a is the assembly gap filling ratio, which is 1 when the gap is completely filled, and δ is the thickness of the indium sheet.

[0041] After determining the thickness and height of the indium sheet used, the cut indium sheet is rolled into a cylindrical indium sheet having the same diameter as the central rod of the resonator or the central hole of the electrode base.

[0042] Step 2. Drive the movable end of the clamp to cooperate with the fixed end of the electrode base clamp to clamp the electrode base. Wrap the cylindrical indium sheet with the same diameter as the center rod of the resonator rolled in step 1 on the center rod of the resonator, and make the lower end of the indium sheet flush with the lower end of the center rod of the resonator. At the same time, apply a certain pre-tightening force to the cylindrical indium sheet at the height of the assembly gap to ensure that the indium sheet will not slip during the subsequent movement of the resonator. Or place the cylindrical indium sheet with the same diameter as the center hole of the electrode base rolled in step 1 in the center hole and on the local heating device without applying any pre-tightening force to the cylindrical indium sheet. Finally, use a non-destructive clamp to clamp the resonator.

[0043] Step 3: The detection device detects the posture of the resonator and the electrode base, and uses a six-axis precision translation stage to adjust the horizontal and rotational postures of the resonator. After meeting the specified parameter requirements, the Z-direction posture of the resonator is adjusted to align the axial holes of the resonator and the electrode base.

[0044] Step 4: The heating device is powered on to heat the resonator, the electrode base and the bottom of the rolled indium sheet. By using the local heating method, the cylindrical indium sheet has a temperature gradient in the height direction. The lower end near the heating device first reaches the melting point of indium, and the upper end away from the heating device reaches the melting point of indium later. After the lower cylindrical indium sheet melts, the upper cylindrical indium sheet slides down and gradually melts under the combined action of gravity and the pulling force of the molten pool, achieving the effect of densely, effectively and evenly filling the assembly gap.

[0045] Step 5: After the cylindrical indium sheet is completely melted, turn off the heating device, wait for the indium to cool and solidify, and complete the indium welding assembly of the resonator and the electrode base.

[0046] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An indium welding process method for an indium welding device of a hemispherical resonant gyroscope based on a temperature gradient, characterized in that: The method is implemented based on a hemispherical resonant gyroscope indium welding device, which includes a gantry, a six-axis precision displacement stage, a non-destructive fixture, a fixture, a heating device, an optical platform and a cylindrical indium sheet. The indium welding objects are the resonator and the electrode base. The gantry and the fixture are fixed on the optical platform, the six-axis precision displacement stage is fixed on the crossbeam of the gantry, and the resonator is fixed on the six-axis precision displacement stage by a non-destructive fixture; the heating device is placed on the optical platform and is located directly below the six-axis precision displacement stage, and the electrode base is fixed on the upper surface of the heating device by a fixture; the cylindrical indium sheet is pre-set on the center rod of the resonator or the center hole of the electrode base before the resonator and the electrode base are assembled; The method comprises the following steps: Step 1: According to the size and assembly gap of the resonator and the electrode base, a cylindrical indium sheet of corresponding thickness and height is rolled; The method for determining the height h of the cylindrical indium sheet is as follows: select an indium sheet of appropriate thickness to reduce the difficulty of assembling the subsequent resonator and electrode base, and determine the height h of the rolled cylindrical indium sheet according to the assembly gap and the thickness of the indium sheet: Where D is the diameter of the center hole of the electrode base, d is the diameter of the center rod of the resonator, H is the height of the assembly gap, a is the filling ratio of the assembly gap, which is 1 when the gap is completely filled, and δ is the thickness of the indium sheet; After determining the thickness and height of the indium sheet to be used, the cut indium sheet is rolled into a cylindrical indium sheet having the same diameter as the central rod of the resonator or the central hole of the electrode base; Step 2, pre-place the cylindrical indium sheet on the central rod of the resonator or the central hole of the electrode base, and fix the resonator with a non-destructive clamp; Step 3: After the detection device detects the postures of the resonator and the electrode base, the six-axis precision translation stage is used to adjust the postures of the resonator in the horizontal and rotational directions. After the specified parameter requirements are met, the posture of the resonator in the Z direction is adjusted to align the shaft holes of the resonator and the electrode base; Step 4: The resonator, the electrode base and the bottom of the cylindrical indium sheet are heated by a heating device. During the heating process, there is a temperature gradient in the height direction of the indium sheet. The indium at the lower end that reaches the melting point first melts first, and the unmelted indium sheet at the upper end slides downward under the action of gravity and the pulling force of the molten pool at the lower end and gradually melts to fill the assembly gap; Step 5: After the cylindrical indium sheet is completely melted, the heating device is turned off, and after the indium is cooled and solidified, the indium welding assembly of the resonator and the electrode base is completed.

2. The indium welding process method of the indium welding device of the hemispherical resonant gyroscope based on temperature gradient according to claim 1, characterized in that: The indium welding device also includes a detection device, which is used to detect the postures of the resonator and the electrode base to ensure that the resonator and the electrode base are in an ideal device posture. The detection device uses a capacitive detection device or a spectral confocal sensor.

3. The indium welding process method of the indium welding device of the hemispherical resonant gyroscope based on temperature gradient according to claim 1 or 2, characterized in that: The clamping force of the non-destructive clamp is adjustable.

4. The indium welding process method of the indium welding device of the hemispherical resonant gyroscope based on temperature gradient as claimed in claim 3, characterized in that: Before assembling the resonator and the electrode base in step 2, a pre-tightening force is applied to the lower end of the cylindrical indium sheet to fix it on the central rod of the resonator, or the cylindrical indium sheet is freely placed in the central hole of the electrode base.

5. The indium welding process method of the indium welding device of the hemispherical resonant gyroscope based on temperature gradient as claimed in claim 4, characterized in that: The indium welding process method of the hemispherical resonant gyroscope indium welding device is applied in a vacuum environment or a normal pressure environment.

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