CN110207963A - Air spring resilient support erects structure freedom-free boundary simulator - Google Patents

Abstract

It is flexibly supported the present invention relates to a kind of air spring and erects structure freedom-free boundary simulator; testpieces is straightened support; switching tooling is arranged in testpieces lower surface; the lower surface of the switching tooling is evenly distributed with several air springs; setting displacement protection block between two air springs adjacent to each other; each air spring connects corresponding air spring additional air chamber away from one end of testpieces; each air spring additional air chamber is fixed on test stationary plane; each displacement protection block also is secured to test stationary plane, and corresponding air spring pressure gauge is arranged on each air spring.It carries out freedom-free boundary simulation test by the support of optimization air spring and layout, to the testpieces of setting, and provides multiple protective, it is ensured that test validity and safety.

Description

Free-free boundary simulation device for vertical structure elastically supported by air spring

technical field

The invention relates to a free-free boundary simulation device for an air spring elastically supporting a vertical structure, belonging to the field of structural dynamic test equipment.

Background technique

The structural dynamic characteristic test is a routine and important link in the product development process. The general purpose of the test is to assess the dynamic characteristic parameters of the structure in the real state of the product; for launch spacecraft and missile weapons, it can provide attitude control It can stabilize the important design parameters of the system, and can also provide important parameters for theoretical prediction model correction; it can also be used for structural health detection and discovery of structural design defects, etc. The product state is a decisive factor to determine the structural dynamic characteristic parameters. Therefore, how to ensure the state of the test product at the test site safely, efficiently and at low cost is an important link in the early planning and test implementation process of the structural dynamic characteristic test.

In order to ensure the boundary conditions of the test product, the structural dynamic characteristic test generally requires a complex boundary simulation system, which is usually carried out in a dedicated test site, such as the vibrating tower for the full-scale test of launch vehicles and missiles. For section and subsystem-level test pieces, generally, a gantry frame is built at the test site, or a site crane is used for horizontal suspension or horizontal support to realize the free-free boundary conditions of the simulated test products.

But for the test product with following series of problems, there are following problems in the prior art:

(1) There is a problem of insufficient lifting height in the test site;

(2) There is a problem of insufficient crane lifting capacity in the test site;

(3) The final assembly of test products requires a firm, stable and safe boundary support;

(4) The test product is vertically assembled, and the lifting and turning functions of the test product cannot be realized after the final assembly.

Contents of the invention

(1) Technical problems to be solved

Aiming at the above-mentioned deficiencies and demands in the prior art, the present invention proposes a free-free boundary simulation device for an air spring elastically supporting a vertical structure, by optimizing the support and layout of the air spring, a free-free boundary simulation test is carried out on the vertical test piece, And provide multiple protections to ensure the effectiveness and safety of the test.

(2) Technical solutions

An air spring elastic support vertical structure free-free boundary simulation device, the test piece is vertically supported, the lower surface of the test piece is provided with a transfer tool, and a number of air springs are evenly distributed on the lower surface of the transfer tool, and two air springs adjacent to each other Displacement protection blocks are arranged between the springs. The end of each air spring facing away from the test piece is connected to the corresponding air spring additional air chamber. The additional air chambers of each air spring are fixed on the test fixed surface, and each displacement protection block is also fixed on the test fixed surface. A corresponding air spring pressure gauge is set on the spring.

Air springs are arranged on the lower end surface of the test piece in an upright state and distributed along its circumference.

The upper part of the test piece is provided with a wrapping belt that surrounds and tightly wraps the outer diameter of the test piece. On the wrapping belt, several elastic support belts extending radially along the test piece are evenly distributed, and the elastic support belt includes ropes and elastic elements. , the rope is a steel wire rope or a nylon rope, and the elastic element is a spring or a rubber rope.

Each of the additional air chambers of the air springs is connected to the gas transmission pipeline through its own gas transmission pipeline branch, and the corresponding air spring gas transmission valve is set on each gas transmission pipeline branch, and the gas source switch valve is set on the gas transmission pipeline, and the gas transmission pipeline is connected to the gas source.

According to the support requirements and mass distribution characteristics of the erected test piece, determine the number and layout of the air springs.

The number of air springs is 3, and the support system is a statically indeterminate system. The target working pressure value of the air springs is determined according to the mass distribution characteristics of the test piece.

The number of air springs is more than 4, and the support system is a statically indeterminate system. To convert the statically indeterminate problem: first establish the system force and moment balance equation, and then establish the optimization objective function with the average value of the target working pressure of the air spring as the target value. Based on the theoretical mass distribution state of the test piece, the target pressure value of each air spring is obtained.

According to the requirements of the support frequency, the additional air chamber of the air spring is designed.

According to the stiffness and stability requirements of the system, the stiffness of the spring is designed.

A method for using an air spring elastically supporting a vertical structure free-free boundary simulation device, comprising the following steps:

S1. Fix the transfer tool and the air spring in place, and connect the test piece in the upright state to the transfer tool and carry it with the displacement protection block;

S2. Install straps, springs and wire ropes to prevent the test piece from tipping over;

S3. Open the air source switch valve of the air source, synchronously control the opening state of the air spring air delivery valve, and monitor each air spring pressure gauge;

S4. When there is a height gap between the transfer tooling and the displacement protection block, cooperatively control the opening of the air spring air delivery valve at the place where the gap does not appear, so as to ensure that the test piece in the erect state is vertically stable and forms a safe and stable support height with the displacement protection block;

S5. In this supporting state, set the target working pressure value of each air spring, and use the air source to perform closed-loop control on it;

S6. Carry out a test.

(3) Beneficial effects

A free-free boundary simulation device for an erected structure supported by an air spring elastically according to the present invention uses an air spring bottom support method to simulate the free-free boundary of a test piece in an upright state. In order to ensure the upright state of the test piece, the transfer tool is used to connect the air spring and the test piece, that is, the bottom support method is adopted, and the static strength requirement of the transfer tool is reduced to ensure that the boundary simulation system has a small additional quality impact on the test results ;

Refer to the reference value of the first-order elastic frequency of the free boundary of the test product, including the first-order frequency of transverse, torsional and longitudinal elasticity, and preliminarily determine the air spring support system according to the relevant standard requirements for the ratio of rigid body frequency and elastic frequency to the free boundary of the structural dynamic characteristic test. Stiffness design requirements and distribution scheme;

Referring to the quality characteristics of the test piece and the stiffness and distribution of the air spring, in order to meet the lateral stability of the test system, a lateral protection device and a limit safety device are designed;

Select the type of air spring and refine the air supply system of multiple sets of air springs, which can realize the synchronization and independent control ability of each set of air springs, and meet the use requirements of inconsistent loads between air springs due to the eccentricity of the test piece;

For the state of four or more air spring supports, by transforming the statically indeterminate problem into a force balance equation and an optimization problem of the objective function, the control of the clear target pressure value of the system is realized, and the free boundary simulation of the system is realized.

Description of drawings

Fig. 1 is a three-dimensional view of the supporting state of an air spring elastically supporting a vertical structure free-free boundary simulation device of the present invention.

Fig. 2 is a schematic diagram of the overall control of a free-free boundary simulation device for an air spring elastically supporting a vertical structure of the present invention.

In the figure, 1-test piece; 2-transfer tooling; 3-displacement protection block; 4-air spring; 5-air spring additional air chamber; 6-air spring pressure gauge; 7-wire rope; 8-spring; 9- Taping; 10-air source; 11-gas pipeline; 12-air source switch valve; 13-air spring gas delivery valve.

Detailed ways

Referring to Fig. 1, a kind of air spring elastic support vertical structure free-free boundary simulation device of the present invention, the test piece 1 is vertically supported, and the lower surface of the test piece 1 is provided with a transfer tool 2, and the lower surface of the transfer tool 2 is uniform. A number of air springs 4 are laid out, and a displacement protection block 3 is arranged between two adjacent air springs. The end of each air spring 4 facing away from the test piece 1 is connected to the corresponding air spring additional air chamber 5, and each air spring additional air chamber 5 is fixed. On the test fixed surface, each displacement protection block 3 is also fixed on the test fixed surface, and each air spring 4 is provided with a corresponding air spring pressure gauge 6 .

The air springs 4 are arranged on the lower end surface of the test piece 1 in the upright state and distributed evenly along its circumference.

Referring to Fig. 2, the upper part of the test piece 1 is provided with a wrapping band 9 surrounding and tightly wrapping the outer diameter of the test piece 1, and several elastic support bands extending radially along the test piece 1 are evenly distributed on the wrapping band 9, so Said elastic supporting belt comprises steel wire rope 7 and spring 8, and the combination of nylon rope and elastic rope can also be used.

Each additional air chamber 5 of the air spring is connected to the gas pipeline 11 through its respective gas pipeline branch, and a corresponding air spring gas transmission valve 13 is set on each gas transmission pipeline branch, and an air source switch valve is set on the gas transmission pipeline 11 12 , the gas pipeline 11 is connected to the gas source 10 .

According to the support requirements and mass distribution characteristics of the vertical test piece 1, the number of air springs 4 is determined.

The number of air springs 4 is 3, and the support system is a statically indeterminate system. The target working pressure value of the air springs 4 is determined according to the mass distribution characteristics of the test piece 1.

The number of air springs 4 is more than 4, and the support system is a statically indeterminate system. To convert the hyperstatically indeterminate problem: first establish the system force and moment balance equation, and then establish the optimization target with the average value of the target working pressure of the air spring 4 as the target value function, and then based on the theoretical mass distribution state of the test piece 1, the target pressure value of each air spring 4 is obtained.

According to the requirements of the support frequency, the additional air chamber 5 of the air spring is designed.

According to the stiffness and stability requirements of the system, the stiffness of the spring 8 is designed.

A method for using an air spring elastically supporting a vertical structure free-free boundary simulation device, comprising the following steps:

S1. Fix the transfer tooling 2 and the air spring 4 in place, and connect the test piece 1 in the upright state to the transfer tooling 2 and carry it with the displacement protection block 3;

S2, install the strap 9, the spring 8 and the steel wire rope 7, to prevent the test piece 1 from toppling over;

S3, open the air source switching valve 12 of the air source 10, synchronously control the opening state of the air spring air delivery valve 13, and monitor each air spring pressure gauge 6;

S4. When there is a height gap between the transfer tooling 2 and the displacement protection block 3, the air spring gas delivery valve 13 at the place where no gap occurs is cooperatively controlled to open, so as to ensure that the test piece 1 in the erect state is vertically stable and forms a safe space with the displacement protection block 3 stable support height;

S5. In this support state, set the target working pressure value of each air spring 4, and use the air source 10 to perform closed-loop control on it;

S6. Carry out a test.

Claims (10)

1. an air spring elastic support vertical structure free-free boundary simulation device is characterized in that, the test piece is supported upright, and the lower surface of the test piece is provided with a transfer frock, and the lower surface of the transfer frock is evenly distributed with some air springs, A displacement protection block is set between two adjacent air springs. The end of each air spring facing away from the test piece is connected to the corresponding air spring additional air chamber. Each air spring additional air chamber is fixed on the test fixed surface, and each displacement protection block is also fixed on the test piece. Test the fixed surface, and set the corresponding air spring pressure gauge on each air spring. 2. The device for simulating the free-free boundary of a vertical structure supported by an air spring elastically according to claim 1, wherein the air spring is arranged on the lower end surface of the test piece in the erect state and distributed along its circumference. 3. a kind of air spring elastic support vertical structure free-free boundary simulation device as claimed in claim 1, it is characterized in that, the upper part of the test piece is provided with a wrapping belt that surrounds and tightly wraps the outer diameter of the test piece, and the wrapping belt A plurality of elastic support belts extending radially along the test piece are evenly distributed on it, and the elastic support belts include ropes and elastic elements, the ropes are steel wire ropes or nylon ropes, and the elastic elements are springs or rubber ropes. 4. a kind of air spring elastically supported vertical structure free-free boundary simulation device as claimed in claim 3, is characterized in that, each additional air chamber of said air spring is connected to the gas pipeline through respective gas pipeline branches, Corresponding air spring gas delivery valves are set on each branch of the gas delivery pipeline, an air source switching valve is set on the gas delivery pipeline, and the gas delivery pipeline is connected to the gas source. 5. a kind of air spring elastic support vertical structure free-free boundary simulation device as claimed in claim 4, is characterized in that, according to the support requirement and mass distribution characteristics of the erected test piece, determine the setting quantity and layout scheme of air spring . 6. a kind of air spring elastic support vertical structure free-free boundary simulation device as claimed in claim 5, is characterized in that, the air spring quantity is 3, and support system is a statically indeterminate system, and the air spring is determined according to the mass distribution characteristics of the test piece. The target operating pressure value of the spring. 7. A kind of air spring elastic support vertical structure free-free boundary simulation device as claimed in claim 5, it is characterized in that, the air spring quantity is more than 4, and the support system is a statically indeterminate system, and the statically indeterminate problem is carried out Conversion: first establish the system force and moment balance equation, then establish the optimization objective function with the average value of the target working pressure of the air spring as the target value, and then obtain the target pressure value of each air spring based on the theoretical mass distribution state of the test piece. 8. A free-free boundary simulation device for an air spring elastically supporting a vertical structure according to claim 6 or 7, characterized in that the additional air chamber of the air spring is designed according to the requirements of the support frequency. 9. A free-free boundary simulation device for an air spring elastically supporting a vertical structure according to claim 8, wherein the spring stiffness is designed according to the stiffness and stability requirements of the system. 10. The method for using an air spring elastic support vertical structure free-free boundary simulation device according to claim 9, characterized in that it comprises the following steps: S1. Fix the transfer tool and the air spring in place, and connect the test piece in the upright state to the transfer tool and carry it with the displacement protection block; S2. Install straps, springs and wire ropes to prevent the test piece from tipping over; S3. Open the air source switch valve of the air source, synchronously control the opening state of the air spring air delivery valve, and monitor each air spring pressure gauge; S4. When there is a height gap between the transfer tooling and the displacement protection block, cooperatively control the opening of the air spring air delivery valve at the place where the gap does not appear, so as to ensure that the test piece in the erect state is vertically stable and forms a safe and stable support height with the displacement protection block; S5. In this supporting state, set the target working pressure value of each air spring, and use the air source to perform closed-loop control on it; S6. Carry out a test.