CN114353793A - Vibration reduction mounting plate applied to sensitive device - Google Patents

Abstract

The invention relates to a vibration-damping mounting plate applied to a sensitive device, belonging to the technical field of vibration-damping structures for sensitive devices. Adapt and ensure that the center of gravity of the vibration-damping mounting plate coincides with the projection of the center of gravity of the sensitive device mounted on the vibration-damping mounting plate on the bottom, and the vibration-damping mounting plate is provided with several mounting holes and limit piles. The present invention has the advantages that it can attenuate high-frequency and small-amplitude vibrations while facilitating heat dissipation of the device, effectively eliminating the influence of temperature changes on the IMU; and the structure is simple in design, convenient for processing and production, and has wide application fields.

Description

A vibration damping mounting plate applied to sensitive devices

technical field

The invention relates to the technical field of vibration-damping structures for sensitive devices, in particular to a vibration-damping mounting plate for a polyoxymethylene-based inertial navigation system and a preparation method.

Background technique

Inertial navigation system is widely used in aircraft, missiles and rockets and other aviation vehicles, ships, etc. Military and civilian navigation systems.

As the core component of inertial navigation system, IMU (Inertial Measuring Unit, IMU) consists of gyroscope and accelerometer. These components are very sensitive to vibration and temperature. A large number of data show that temperature change and high-frequency vibration are important factors that affect the measurement value of IMU. But in actual use, vibration and temperature changes are unavoidable. However, the IMU sensor is light in weight and small in size, and has high requirements on the vibration environment, so the design of its vibration reduction structure has always been a design difficulty. According to data analysis, the impact sensitive area of the inertial measurement module (IMU) is about 10 kHz high frequency, and it is necessary to effectively attenuate the high frequency impact stress wave and impact energy, otherwise it will suffer secondary damage from the impact stress wave.

Most of the vibration damping devices used in inertial navigation systems disclosed in the prior art have complex structures or are troublesome to install. There are also technologies that use rubber vibration damping pads between the IMU and the bracket. The isolation effect is good, but it is mostly used in the internal installation method, which is suitable for small-volume devices and is not conducive to heat dissipation.

Therefore, how to reduce the impact of low-frequency and large-amplitude vibration on the inertial components of IMUs and improve the measurement accuracy of the inertial components has always been the focus of research in the field of inertial navigation. The Chinese patent with the patent number CN111016033B discloses "a silica gel-based IMU vibration reduction and heat insulation device and its preparation method". The structure and installation method are still relatively complicated, and the heat dissipation effect is not good.

There is an urgent need in the market for a device to be fixed on the aircraft, in which each component is synchronized with the aircraft to reduce dynamic errors caused by vibration, shock and angular motion, and has a good heat dissipation effect, which can effectively reduce or eliminate temperature drift errors; the structure is simpler, and the installation and use are easier. Easy vibration damping mounting plate for convenient inertial navigation systems.

SUMMARY OF THE INVENTION

The present invention overcomes the shortcomings in the prior art, provides a simple structure, is easy to use, and when fixed on an aircraft, can keep the original parts of the IMU inertial assembly synchronized with the aircraft, reduce dynamic errors caused by vibration, impact and angular motion, and A vibration-absorbing mounting plate for inertial navigation systems that keeps it at a constant temperature and reduces temperature drift errors.

The technical solution is as follows: a vibration damping mounting plate applied to a sensitive device, the vibration damping mounting plate is an integrally formed plate-like structure, and its cross-sectional shape is adapted to the shape of the sensitive device and ensures the vibration damping The center of gravity of the mounting plate coincides with the projection of the center of gravity of the sensitive device mounted on the vibration-damping mounting plate on the bottom, and the vibration-damping mounting plate is provided with a number of mounting holes and limit piles.

Further, there are several installation holes, and all the installation holes are symmetrical about the center.

Further, the cross-section of the limit pile is circular, oval or oblong.

Further, the cross section of the vibration damping mounting plate is rectangular, square, circular or oval.

Further, the vibration-damping mounting plate is an integrally formed square plate, the mounting holes are arranged on the four corners and the diagonal lines of the vibration-damping mounting plate, and there are two limit piles arranged diagonally. They are respectively a first limit pile with a circular cross section and a second limit pile with an oblong cross section.

Further, the vibration damping mounting plate is polyoxymethylene plastic, and the polyoxymethylene plastic is homopolyoxymethylene.

Further, the vibration damping mounting plate is injection-molded from homopolyoxymethylene with different properties and then mechanically cut into a shape suitable for the sensitive device.

Further, the sensitive device includes a gyroscope and an accelerometer.

The advantages of the present invention are:

1) The present invention can attenuate high-frequency and small-amplitude vibration, and at the same time, it can be beneficial to the heat dissipation of the device, and effectively eliminate the influence of temperature changes on the IMU;

2) The structure of the present invention is simple in design, integrates the functions of installation and fixation, vibration reduction and heat insulation, and adopts the external installation method to fix the original parts of the inertial navigation system and the aircraft synchronously, reducing the dynamic error caused by vibration, impact and angular motion and dissipating heat at the same time. The effect is good, the temperature drift error is reduced, the installation is convenient and fast, and it meets the high standard requirements of the inertial navigation system for vibration reduction and heat insulation;

3) The structure preparation process of the present invention is integrally formed, which is convenient for processing and production, the material polyoxymethylene used has low cost, and the production process is safe and simple, which is suitable for industrial application, and can be adjusted according to the characteristics of the polyoxymethylene material itself, by adjusting the material ratio and the degree of polymerization. It can withstand vibration damping and thermal insulation of devices with higher density and heavier weight, and has a wide range of applications.

Description of drawings

1 is a schematic structural diagram of a vibration-damping mounting plate applied to a sensitive device according to Embodiment 1 of the present invention;

Fig. 2 Vibration spectrum shape shown in experimental example 1;

As shown in the figure: 1. Vibration reduction mounting plate; 2. The first limit pile; 3. The second limit pile; 4. The installation hole.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the implementations. example. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that each installation method and each technical term mentioned in the present invention are technical terms that have been clearly known in the technical field for a long time, so no further explanation will be given. In addition, the same reference numerals are used for the same components, but this does not affect and should not constitute the accurate understanding of the technical solution by those skilled in the art.

Example 1

As shown in FIG. 1 , the present embodiment discloses a vibration-damping mounting plate applied to an inertial navigation system. The vibration-damping mounting plate 1 is an integrally formed square plate that is injection-molded with a polyoxymethylene resin and is mechanically cut to reduce vibration. Several mounting holes 4 and two limit piles (the first limit pile 2 and the second limit pile 3) are opened on the mounting plate, and the several mounting holes are respectively arranged on the four corners and diagonal lines of the vibration reduction mounting plate. The two limit piles are arranged diagonally, wherein the first limit pile 2 is a cylindrical limit pile with a circular cross-section, and the second limit pile 3 is an oblong pile with an oblong cross-section (to prevent the sensitive device from generating a circumference. motion, constrained angular motion).

In specific use, the inertial navigation system is placed on the vibration-damping mounting plate in Example 1, positioned through the limit pile, and then passed through the mounting hole through the bolt, and the other side is fixed with a nut. The inertial navigation system is fixed on the vibration-damping mounting plate in Embodiment 1 of the present invention, and then the vibration-damping mounting plate on which the inertial navigation system is fixed is mounted on the corresponding aircraft.

It should be noted that the plate shape with a square cross-section is only an example of the main body 1 of the vibration-damping mounting plate of the present invention. In fact, it can be made into any shape as required, such as a plate with a rectangular, circular, or elliptical cross-section, etc. . The size of the vibration-damping mounting plate should be adjusted according to the actual size of the inertial navigation system, and the thickness of the main body 1 of the vibration-damping mounting plate can also be adjusted to meet different degrees of installation, vibration-damping and thermal insulation requirements;

In addition, within the acceptable range of the size of the sensitive device, the two limit piles can be as long as possible when setting, so as to reduce the error and improve the vibration reduction accuracy;

The polyoxymethylene used to manufacture the vibration damping mounting plate can also prepare polyoxymethylene resins with different elastic moduli and physical and chemical properties according to different process ratios, and reduce the linear motion of sensitive devices through the characteristics of the material itself; The setup of the pile strictly constrains the angular motion of the sensitive device.

Experimental Example 1 Using the vibration-damping mounting plate of Example 1 to conduct a functional vibration test of the inertial measurement module

For the inertial measurement module (IMU) of the model YTDL-M20 applied to the special underwater carrier, the vibration test was carried out after the vibration reduction mounting plate of Example 1 was installed. The test method, test conditions, test process and The test indicators are as follows:

(1) Test method: refer to the standard GJB 150.16A-2009 Laboratory Environmental Test Methods for Military Equipment Part 16: Vibration Test;

GJB 7592-2012 Vibration gyroscope test method;

GJB 1037A-2004 Test method for uniaxial pendulum servo linear accelerometer;

(2) Test conditions: 2.1 Test environment requirements: a) Ambient temperature: 15℃~35℃; b) Relative humidity: 20%~80%; c) Air pressure: atmospheric pressure at the test site.

Site and power supply requirements: a) The foundation of the test bench in the test site should be stable, and the test bench should meet the standard requirements; b) The test site should have a good grounding and magnetic environment; c) Except for special instructions, the IMU is powered by the test board, and the power supply voltage is 5V ±0.02V.

(3) Test process: a) After the IMU is installed with the vibration damping device, install it on the vibration table together with the vibration bracket, the X axis is parallel to the vibration direction, connect the test cable, and confirm that the cable connection is correct;

b) The IMU is powered on, and the sampling data is recorded for 3 minutes;

c) Start the shaking table, apply vibration according to the test conditions shown in Figure 2-Vibration spectrum, and record the sampling data for 3 minutes when the shaking table reaches the specified level;

d) After the vibration is over, record the sampling data for 3 minutes, and the IMU is powered off after the sampling is over;

e) The Y and Z axis tests are the same as before.

After the test, check the appearance of the product for loose fasteners and structural damage; during the test, check whether the electrical and mechanical properties of the product are normal, and whether the gyro bias changes during and after the test meet the technical requirements.

(4) Technical index requirements: the zero bias change of the vibrating gyroscope: better than 2°/h; the zero bias change of the vibrating accelerometer: better than 1 mg;

(5) The test results are shown in Table 1 (for the calculation method of vibration accuracy of gyroscope and accelerometer, please refer to the relevant records in GJB 2504-95 General Specification for Quartz Flexible Accelerometer and GJB 7592-2012 Vibration Gyroscope Test Method).

Table 1 Test results of vibration test

in conclusion:

Use a shaking table to vibrate the device under test according to Figure 2-Vibration spectrum shape, test the zero-bias change of the device under test, and sample data for 3 minutes before vibration, during vibration, and after vibration. The results are shown in the table, the numerical change of the device under test before and after the vibration is much smaller than the error index of the vibration accuracy, indicating that the applied vibration does not cause functional damage to the accuracy of the device under test. The mean value of the data before and after the vibration and the change of the value in the vibration are within the error range of the vibration accuracy index, indicating that the external installation structure has a certain vibration reduction effect during the vibration process and achieves the functional index of equipment accuracy.

After the test, the product was visually inspected, and there was no loose fasteners and structural damage; during the test, the electrical and mechanical properties of the product were checked to be normal, and the zero bias changes of the gyroscope and accelerometer during and after the test also met the technical requirements.

For those skilled in the art, the present invention is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention; therefore, From any point of view, the embodiments should be considered as exemplary rather than restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is therefore intended that the scope of the present invention will fall within the scope of the claims. All changes within the meaning and range of equivalent requirements are included in the present invention. Any reference signs in the claims shall not be construed as limiting the involved claim.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any minor modifications, equivalent replacements and improvements made to the above embodiments according to the technical essence of the present invention shall include It is within the protection scope of the technical solution created by the present invention.

Claims (8)

1. A vibration-damping mounting plate applied to a sensitive device, characterized in that the vibration-damping mounting plate is an integrally formed plate-like structure, and its cross-sectional shape is adapted to the shape of the sensitive device and ensures the The center of gravity of the vibration-absorbing mounting plate coincides with the projection of the center of gravity of the sensitive device mounted on the vibration-absorbing mounting plate on the bottom, and the vibration-absorbing mounting plate is provided with a number of mounting holes and limit piles. 2 . The vibration-damping mounting plate applied to a sensitive device according to claim 1 , wherein there are several mounting holes, and all the mounting holes are symmetrical about the center. 3 . 3 . The vibration-damping mounting plate applied to a sensitive device according to claim 1 , wherein the cross-section of the limiting pile is circular, elliptical or oval. 4 . 4 . The vibration-damping mounting plate applied to a sensitive device according to claim 1 , wherein the cross-section of the vibration-damping mounting plate is a rectangle, a square, a circle or an ellipse. 5 . 5 . The vibration-damping mounting plate applied to a sensitive device according to claim 1 , wherein the vibration-damping mounting plate is an integrally formed square plate, and the mounting holes are arranged at four corners of the vibration-damping mounting plate. 6 . And on the diagonal line, there are two limit piles and are arranged diagonally, which are a first limit pile with a circular cross-section and a second limit pile with an oblong cross-section. 6 . The vibration damping mounting plate applied to a sensitive device according to claim 1 , wherein the vibration damping mounting plate is polyoxymethylene plastic, and the polyoxymethylene plastic is homopolyoxymethylene. 7 . 7 . The vibration-damping mounting plate applied to a sensitive device according to claim 6 , wherein the vibration-damping mounting plate is made of homopolyoxymethylene with different properties after injection molding and is mechanically cut into the same shape as the sensitive device. 8 . adapted shape. 8 . The vibration reduction mounting plate applied to a sensitive device according to claim 1 , wherein the sensitive device comprises a gyroscope and an accelerometer. 9 .

Images