Accelerometer assembly device and assembly method

Abstract

The application relates to the mechanical technical field and discloses an accelerometer assembling device and an assembling method. The device comprises a concentric seat, a base, a guide element and a positioning element. The concentric seat comprises upper and lower bottom plates and a supporting side plate arranged between the upper and lower bottom plates. The upper bottom plate is provided with a first through hole, and the lower bottom plate is provided with a second through hole. The central axes of the first through hole and the second through hole are collinear. The lower end of the base is arranged in the second through hole, the upper end of the base is provided with a lower torque device of the accelerometer, and the upper end of the base is provided with a surface through hole and a positioning mark. The positioning mark is used for determining the setting positions of three bosses of a swing assembly of the accelerometer and the position of the upper end face of the lower torque device for smearing adhesive. The swing assembly is positioned by cooperating with the surface through hole through the positioning element. The lower end of the guide element is arranged on the swing assembly and is provided with three bosses. The three bosses of the guide element are matched with the three bosses of the swing assembly. The upper end of the guide element is arranged in the first through hole. Thus, the accelerometer can be assembled with low pre-tightening force.

Description

Technical Field

[0001] This invention relates to the field of mechanical technology, and in particular to an accelerometer assembly device and assembly method. Background Technology

[0002] Quartz flexible accelerometers, as a type of linear acceleration sensor, are widely used in inertial navigation, track mapping, oil exploration and other fields.

[0003] The core component of a quartz flexural accelerometer is the movement, which is assembled from upper and lower torquers, a central pendulum assembly, and an outer band. Because the permanent magnets of the upper and lower torquers are magnetized in the same direction, they repel each other. Therefore, to assemble them together, a certain preload must be applied to press the upper and lower torquers together and counteract their repulsive force. For example, during the assembly of the movement, a constant preload is first continuously applied between the upper and lower torquers. Then, the two ends of the band are welded circumferentially to the upper and lower torquers. Finally, the preload is removed.

[0004] The preload needs to be controlled within a safe range (50-130N). Excessive preload will cause brittle fracture of the outer ring of the pendulum assembly, directly leading to abrupt changes in the accelerometer output. Insufficient preload will prevent the pendulum assembly from being fixed inside the core, and its movement will cause the internal connecting wires to break, resulting in abnormal accelerometer output. Current methods of applying preload partially overcome the repulsive force of the torque generator magnets and partially compress the pendulum assembly to prevent displacement between the pendulum assembly and the upper and lower torque generators. However, this preload has a side effect: the accelerometer experiences slow stress release, leading to unidirectional drift in the bias and scale factor, resulting in poor output stability. Therefore, it is necessary to reduce or eliminate this preload to improve accelerometer stability. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an accelerometer assembly device and assembly method, which can solve the problems in the prior art.

[0006] The technical solution of the present invention: an accelerometer assembly device, wherein the device includes a concentric seat, a base, a guide element, and a positioning element, wherein,

[0007] The concentric base includes an upper base plate, a lower base plate, and a support side plate disposed between the upper base plate and the lower base plate. The upper base plate has a first through hole, and the lower base plate has a second through hole. The central axes of the first through hole and the second through hole are collinear.

[0008] The lower end of the base is placed in the second through hole, and the upper end of the base is used to set the lower torque device of the accelerometer. The upper end of the base is provided with a surface through hole and a positioning mark. The positioning mark is used to determine the setting position of the three bosses of the accelerometer pendulum assembly and the position of the adhesive applied to the upper end surface of the lower torque device. The pendulum assembly is positioned by the positioning element cooperating with the surface through hole.

[0009] The lower end of the guide element is disposed on the swing assembly and has three protrusions. The three protrusions of the guide element cooperate with the three protrusions of the swing assembly, and the upper end of the guide element is placed in the first through hole.

[0010] Preferably, a groove is provided at the center of the upper end of the base, and the groove is used to house the lower torque device.

[0011] Preferably, a third through hole is provided at the center of the base.

[0012] Preferably, the outer diameter of the lower end of the base is equal to the inner diameter of the second through hole and smaller than the outer diameter of the upper end of the base, and the outer diameter of the upper end of the base is larger than the diameter of the pendulum of the pendulum assembly and smaller than the outer diameter of the middle section of the base.

[0013] Preferably, the upper end of the base is also provided with a base hole for engaging with the terminal block of the lower torque device.

[0014] Preferably, the top of the positioning element mates with a notch on the pendulum assembly, and the bottom mates with a through hole on the surface, so as to achieve the positioning of the pendulum assembly.

[0015] Preferably, the positioning element is a positioning pin, and the guiding element is a guide post.

[0016] Preferably, the material of the concentric base is metal.

[0017] The present invention also provides an accelerometer assembly method, wherein the above-mentioned device is used for assembly, and the method includes:

[0018] Place the lower end of the base into the second through hole of the concentric seat;

[0019] The lower torque device is placed at the upper end of the base, and adhesive is applied to the upper end face position determined by the lower torque device.

[0020] The pendulum assembly is placed on the lower torque device according to the determined setting positions of the three bosses of the pendulum assembly, and the pendulum assembly is positioned by the positioning element cooperating with the surface through hole;

[0021] The lower end of the guide element is placed on the swing assembly, and the upper end of the guide element is placed in the first through hole. The three protrusions of the guide element cooperate with the three protrusions of the swing assembly to perform pressure curing.

[0022] After the adhesive has cured, connect the terminals of the lower torque device to the corresponding positions of the pendulum assembly;

[0023] An upper torque device is installed on the pendulum assembly at a position corresponding to the lower torque device.

[0024] A predetermined preload is applied to the upper torque device and an abdominal belt is fitted on it. One end of the abdominal belt is connected to the upper torque device, and the other end is connected to the lower torque device.

[0025] Preferably, the curing temperature range of the adhesive is 80-100°C, and the curing time range is 2-4 hours.

[0026] Through the above technical solution, during the assembly of the accelerometer, the lower end of the base can be placed in the second through hole of the concentric seat, and then the lower torque unit and the pendulum assembly can be sequentially arranged on the upper end of the base. The positions of the three bosses on the pendulum assembly and the position for applying adhesive to the upper surface of the lower torque unit can be determined by positioning marks. The pendulum assembly is connected to the lower torque unit via adhesive. A guide element can then be installed on the pendulum assembly, with the three bosses at the lower end of the guide element engaging with the three bosses on the pendulum assembly, and the upper end placed in the first through hole of the concentric seat. This ensures that the central axes of all components are collinear during assembly, and the gravity of the guide element can be used to press the adhesive at the bonding position between the pendulum assembly and the lower torque unit. Therefore, only a low preload force is needed to press the upper and lower torque units together, and then the abdominal belt can be fitted. The accelerometer assembly device described in this invention can significantly reduce the clamping force of the pendulum assembly boss, thereby reducing the transmission of stress from the pendulum assembly boss to the pendulum assembly, reducing the accelerometer bias drift, increasing the accelerometer bias stability, and also reducing the risk of breakage of parts such as the outer ring of the pendulum assembly. Attached Figure Description

[0027] 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.

[0028] Figure 1 This is a front view of the base in an embodiment of the present invention;

[0029] Figure 2This is a cross-sectional view of the base along the CC direction in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the positioning pin in an embodiment of the present invention;

[0031] Figure 4 This is a front view of the concentric base in an embodiment of the present invention;

[0032] Figure 5 This is a side view of the concentric seat in an embodiment of the present invention;

[0033] Figure 6 This is a front view of the guide element in an embodiment of the present invention;

[0034] Figure 7 This is a side view of the guide element in an embodiment of the present invention;

[0035] Figure 8 This is a front view of the pendulum component in an embodiment of the present invention;

[0036] Figure 9 This is a flowchart of an accelerometer assembly method provided in an embodiment of the present invention.

[0037] Explanation of reference numerals in the attached figures

[0038] 1. Surface through hole; 2. Base hole; 3. Positioning mark; 4. Third through hole;

[0039] 5. Positioning element; 6. Second through hole; 7a. Upper base plate; 7b. Lower base plate; 7c. Supporting side plate;

[0040] 8. Three bosses of the guide element; 9. Notch; 10. Three bosses of the swing assembly. Detailed Implementation

[0041] Specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. 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.

[0042] 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 according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0043] The accelerometer assembly device provided in this embodiment of the invention can be used for assembling quartz flexible accelerometers.

[0044] refer to Figures 1-8This invention provides an accelerometer assembly device, which includes a concentric seat, a base, a guide element, and a positioning element 5.

[0045] The concentric base includes an upper base plate 7a, a lower base plate 7b, and a support side plate 7c disposed between the upper base plate 7a and the lower base plate 7b. The upper base plate 7a has a first through hole, and the lower base plate 7b has a second through hole 6. The central axes of the first through hole and the second through hole 6 are collinear.

[0046] The lower end of the base is placed in the second through hole 6, and the upper end of the base is used to set the lower torque device of the accelerometer. The upper end of the base is provided with a surface through hole 1 and a positioning mark 3. The positioning mark 3 is used to determine the setting position of the three bosses 10 of the pendulum assembly of the accelerometer and the position of the adhesive applied to the upper end surface of the lower torque device. The pendulum assembly is positioned by the positioning element 5 cooperating with the surface through hole 1.

[0047] The lower end of the guide element is disposed on the swing assembly and has three protrusions 8. The three protrusions 8 of the guide element cooperate with the three protrusions 10 of the swing assembly. The upper end of the guide element is placed in the first through hole.

[0048] Through the above technical solution, during the assembly of the accelerometer, the lower end of the base can be placed in the second through hole of the concentric seat, and then the lower torque unit and the pendulum assembly can be sequentially arranged on the upper end of the base. The positions of the three bosses on the pendulum assembly and the position for applying adhesive to the upper surface of the lower torque unit can be determined by positioning marks. The pendulum assembly is connected to the lower torque unit via adhesive. A guide element can then be installed on the pendulum assembly, with the three bosses at the lower end of the guide element engaging with the three bosses on the pendulum assembly, and the upper end placed in the first through hole of the concentric seat. This ensures that the central axes of all components are collinear during assembly, and the gravity of the guide element can be used to press the adhesive at the bonding position between the pendulum assembly and the lower torque unit. Therefore, only a low preload force is needed to press the upper and lower torque units together, and then the abdominal belt can be fitted. The accelerometer assembly device described in this invention can significantly reduce the clamping force of the pendulum assembly boss, thereby reducing the transmission of stress from the pendulum assembly boss to the pendulum assembly, reducing the accelerometer bias drift, increasing the accelerometer bias stability, and also reducing the risk of breakage of parts such as the outer ring of the pendulum assembly.

[0049] According to one embodiment of the present invention, the concentric base can be I-shaped, that is, the upper base plate 7a and the lower base plate 7b are parallel.

[0050] Alternatively, the concentric base can also be a horizontally placed U-shape, such as... Figure 5 As shown.

[0051] According to one embodiment of the present invention, a groove is provided at the center of the upper end of the base, and the groove is used to house the lower torque device.

[0052] By adding grooves, the lower torque device can be better secured.

[0053] According to one embodiment of the present invention, a third through hole 4 is provided at the center of the base.

[0054] For example, the diameter of the third through hole ranges from 5 mm to 10 mm.

[0055] If the lower torque device is too tightly fitted in the groove after the lower torque device and the pendulum assembly are bonded together, a cylinder that matches the third through hole can be used to apply upward force through the third through hole to push the torque device out.

[0056] According to one embodiment of the present invention, the outer diameter of the lower end of the base is equal to the inner diameter of the second through hole 6 and smaller than the outer diameter of the upper end of the base, and the outer diameter of the upper end of the base is larger than the diameter of the pendulum plate of the pendulum assembly and smaller than the outer diameter of the middle section of the base.

[0057] For example, the base can be composed of three cylinders with collinear and connected central axes. The lower end of the base corresponds to the bottom cylinder, whose height is less than or equal to the thickness of the bottom plate 7b. The upper end of the base corresponds to the top cylinder, whose outer diameter is 10mm to 20mm larger than the diameter of the pendulum plate of the pendulum assembly. The middle section of the base corresponds to the middle cylinder.

[0058] According to one embodiment of the present invention, the positioning mark 3 can be a positioning groove, and the number of positioning grooves can be three. Each positioning groove corresponds to the setting position of a boss and a gluing position.

[0059] For example, the width of the positioning groove ranges from 5 ± 0.1 mm.

[0060] According to one embodiment of the present invention, the upper end of the base is further provided with a base hole 2 for cooperating with the terminal block of the lower torque device.

[0061] In other words, the terminal block of the lower torque device can be positioned in the base hole to better prevent the lower torque device from moving.

[0062] For example, the diameter of the base hole ranges from 5 ± 0.1 mm.

[0063] According to one embodiment of the present invention, the top of the positioning element 5 engages with the notch 9 provided on the pendulum assembly, and the bottom engages with the surface through hole 1 to achieve the positioning of the pendulum assembly.

[0064] More specifically, the notch (such as a rectangular notch) on the outer edge of the pendulum assembly corresponds to the position of the surface through hole. The positioning element is inserted into the surface through hole through the notch, and the positioning of the pendulum assembly is achieved through the cooperation of the notch, the positioning element and the through hole.

[0065] For example, the width of the surface through hole ranges from 2±0.1mm, and the length ranges from 3±0.1mm. The width of the surface through hole is the same as the notch width of the pendulum assembly.

[0066] According to one embodiment of the present invention, the positioning element 5 is a positioning pin, and the guiding element is a guide post.

[0067] The three protrusions of the guide post can be larger than the three protrusions of the pendulum assembly, for example, slightly larger. The total height of the guide post should not exceed 200mm, and the specific height can be determined based on the height of the base and the concentric seat; this invention does not limit this.

[0068] For example, the total height of the guide post is 150mm, of which the diameter is 25mm, the height of the boss is 5mm, and the height of the part excluding the boss is 145mm.

[0069] According to one embodiment of the present invention, the material of the concentric base is metal.

[0070] For example, the concentric base can be made of a metal material with a low coefficient of thermal expansion, such as beryllium bronze.

[0071] According to one embodiment of the present invention, in order to prevent deformation of the concentric seat, the thickness of the upper base plate 7a, the lower base plate 7b and the supporting side plate 7c is preferably not less than 5mm.

[0072] According to one embodiment of the present invention, the diameter of the first through hole and the second through hole 6 ranges from 10 mm to 25 mm.

[0073] Figure 9 This is a flowchart illustrating an accelerometer assembly method provided by an embodiment of the present invention. This method can be used for assembling quartz flexible accelerometers.

[0074] like Figure 9 As shown in the figure, this embodiment of the invention also provides an accelerometer assembly method, wherein the assembly is performed using the device described in the above embodiments, and the method includes:

[0075] S100, place the lower end of the base into the second through hole of the concentric seat;

[0076] S102, the lower torque device is placed on the upper end of the base and adhesive is applied to the upper end face position determined by the lower torque device;

[0077] The adhesive is a non-elastic adhesive (e.g., coefficient of linear expansion ≤ 3 × 10⁻⁶ / ℃).

[0078] S104, the pendulum assembly is placed on the lower torque device according to the determined setting positions of the three bosses of the pendulum assembly, and the pendulum assembly is positioned by the positioning element cooperating with the surface through hole;

[0079] In this step, if the pendulum component is not perfectly aligned at first, it can be moved once to avoid reducing the adhesive bonding strength due to multiple moves.

[0080] That is, the pendulum assembly is placed on the lower torque device and connected by adhesive bonding to fix the position of the lower torque device and the pendulum assembly.

[0081] S106, the lower end of the guide element is placed on the swing assembly, the upper end of the guide element is placed in the first through hole, and the three protrusions of the guide element cooperate with the three protrusions of the swing assembly to perform pressure curing.

[0082] The gravity of the guide element can press the adhesive at the bonding position between the pendulum assembly and the lower torque device, ensuring that the adhesive thickness at the bonding position is as consistent as possible.

[0083] In this step, to ensure bonding strength, some adhesive overflow is allowed. The overflowing adhesive climbs up the boss to form a semi-enclosed structure, which increases bonding and fixing strength after curing.

[0084] S108, After the adhesive has cured, connect the terminals of the lower torque device to the corresponding positions of the pendulum assembly;

[0085] For example, the terminals of the lower torque device and the corresponding positions of the pendulum assembly can be connected with gold wire.

[0086] S110, an upper torque device is provided on the pendulum assembly at a position corresponding to the lower torque device;

[0087] S112, apply a predetermined pre-tightening force to the upper torque device and put on the abdominal belt, one end of the abdominal belt is connected to the upper torque device and the other end is connected to the lower torque device.

[0088] The predetermined preload force can be determined based on the repulsive force between the upper and lower torque devices, as long as it can overcome the repulsive force and minimize the clamping force on the boss position of the swing assembly (≤50N). The tooling for applying the preload force is a commonly used tooling, and will not be described in detail here.

[0089] Through the above technical solution, during the assembly of the accelerometer, the lower end of the base can be placed in the second through hole of the concentric seat, and then the lower torque unit and the pendulum assembly can be sequentially arranged on the upper end of the base. The positions of the three bosses on the pendulum assembly and the position for applying adhesive to the upper surface of the lower torque unit can be determined by positioning marks. The pendulum assembly is connected to the lower torque unit via adhesive. A guide element can then be installed on the pendulum assembly, with the three bosses at the lower end of the guide element engaging with the three bosses on the pendulum assembly, and the upper end placed in the first through hole of the concentric seat. This ensures that the central axes of all components are collinear during assembly, and the gravity of the guide element can be used to press the adhesive at the bonding position between the pendulum assembly and the lower torque unit. Therefore, only a low preload force is needed to press the upper and lower torque units together, and then the abdominal belt can be fitted. The accelerometer assembly method described in this invention can significantly reduce the clamping force of the pendulum assembly boss, thereby reducing the transmission of stress from the pendulum assembly boss to the pendulum assembly, reducing the accelerometer bias drift, increasing the accelerometer bias stability, and also reducing the risk of breakage of the outer ring of the pendulum assembly and the connecting gold wire.

[0090] According to one embodiment of the present invention, the curing heating temperature range of the adhesive is 80 to 100°C, and the curing time range of the adhesive is 2 to 4 hours.

[0091] That is, after the adhesive is heated to 80-100℃ and cured for 2-4 hours, the pendulum component is completely cured on the lower torque device.

[0092] According to one embodiment of the present invention, the abdominal band can be connected to the upper torque device and the lower torque device by welding or gluing.

[0093] For example, in the case of adhesive bonding, the abdominal binder can be connected to the upper and lower torque devices using epoxy adhesive.

[0094] According to one embodiment of the present invention, the method further includes: positioning the terminal of the lower torque device into the base hole to better prevent the lower torque device from moving.

[0095] For example, this step can be performed after S102 or simultaneously with S102.

[0096] Those skilled in the art should understand that the above descriptions of materials, values, and dimensions are merely exemplary and not intended to limit the present invention.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. An accelerometer assembly device, characterized in that, The device includes a concentric seat, a base, a guide element, and a positioning element (5), wherein, The concentric base includes an upper base plate (7a), a lower base plate (7b), and a support side plate (7c) disposed between the upper base plate (7a) and the lower base plate (7b). The upper base plate (7a) has a first through hole, and the lower base plate (7b) has a second through hole (6). The central axes of the first through hole and the second through hole (6) are collinear. The lower end of the base is placed in the second through hole (6), and the upper end of the base is used to set the lower torque device of the accelerometer. The upper end of the base is provided with a surface through hole (1) and a positioning mark (3). The positioning mark (3) is used to determine the setting position of the three bosses (10) of the pendulum assembly of the accelerometer and the position of the upper end surface of the lower torque device to apply adhesive. The pendulum assembly is positioned by the positioning element (5) cooperating with the surface through hole (1). The lower end of the guide element is disposed on the pendulum assembly and has three protrusions (8). The three protrusions (8) of the guide element cooperate with the three protrusions (10) of the pendulum assembly. The upper end of the guide element is placed in the first through hole.

2. The apparatus according to claim 1, characterized in that, A groove is provided at the center of the upper end of the base, and the groove is used to house the lower torque device.

3. The apparatus according to claim 2, characterized in that, The base has a third through hole (4) at its center.

4. The apparatus according to claim 3, characterized in that, The outer diameter of the lower end of the base is equal to the inner diameter of the second through hole (6) and smaller than the outer diameter of the upper end of the base. The outer diameter of the upper end of the base is larger than the diameter of the pendulum of the pendulum assembly and smaller than the outer diameter of the middle section of the base.

5. The apparatus according to claim 4, characterized in that, The upper end of the base is also provided with a base hole (2) for engaging with the terminal block of the lower torque device.

6. The apparatus according to claim 5, characterized in that, The top of the positioning element (5) engages with the notch (9) provided on the pendulum assembly, and the bottom engages with the surface through hole (1) to achieve the positioning of the pendulum assembly.

7. The apparatus according to any one of claims 1-6, characterized in that, The positioning element (5) is a positioning pin, and the guiding element is a guide post.

8. The apparatus according to any one of claims 1-6, characterized in that, The material of the concentric base is metal.

9. An accelerometer assembly method, characterized in that, Assembly using the apparatus of any one of claims 1-8, the method comprising: Place the lower end of the base into the second through hole of the concentric seat; The lower torque device is placed at the upper end of the base, and adhesive is applied to the upper end face position determined by the lower torque device. The pendulum assembly is placed on the lower torque device according to the determined setting positions of the three bosses of the pendulum assembly, and the pendulum assembly is positioned by the positioning element cooperating with the surface through hole; The lower end of the guide element is placed on the swing assembly, and the upper end of the guide element is placed in the first through hole. The three protrusions of the guide element cooperate with the three protrusions of the swing assembly to perform pressure curing. After the adhesive has cured, connect the terminals of the lower torque device to the corresponding positions of the pendulum assembly; An upper torque device is installed on the pendulum assembly at a position corresponding to the lower torque device. A predetermined preload is applied to the upper torque device and an abdominal belt is fitted on it. One end of the abdominal belt is connected to the upper torque device, and the other end is connected to the lower torque device.

10. The method according to claim 9, characterized in that, The curing temperature range of the adhesive is 80-100℃, and the curing time range is 2-4 hours.

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