CN113176156A - Light gas gun test device capable of switching rotatable gun barrel in situ - Google Patents
Light gas gun test device capable of switching rotatable gun barrel in situ Download PDFInfo
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- CN113176156A CN113176156A CN202110231511.4A CN202110231511A CN113176156A CN 113176156 A CN113176156 A CN 113176156A CN 202110231511 A CN202110231511 A CN 202110231511A CN 113176156 A CN113176156 A CN 113176156A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/30—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
- G01N3/307—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight generated by a compressed or tensile-stressed spring; generated by pneumatic or hydraulic means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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Abstract
The invention discloses a light gas gun test device for in-situ switching of rotatable gun barrels, which comprises a multi-gun barrel annular support, a gun barrel cluster, a loading port end socket, an outlet speed measuring end socket and a base, wherein the multi-gun barrel annular support comprises a square support and a chuck, the square support is fixed on the base, and the chuck is arranged in the square support; the gun barrel cluster comprises a plurality of cylindrical gun barrels, and the cylindrical gun barrels are respectively and independently arranged in the chuck and can independently rotate relative to the chuck; the loading port end socket is connected with an energy storage tank and arranged at the inlet of the cylindrical gun barrel; the outlet speed measuring seal head is arranged at the outlet of the cylindrical gun barrel, and the outlet speed measuring seal head is connected with a laser speed measuring system. The invention can directly load non-circular projectiles, can effectively improve the influence of the projectile support on the impact speed and direction of the projectiles, and can effectively solve the requirements of variety of simulated foreign objects and adjustable flying postures of the foreign objects in a foreign object impact damage test by switching functions of a plurality of gun barrels.
Description
Technical Field
The invention relates to a light gas gun test device for in-situ switching of a rotatable gun barrel, and belongs to the field of material and structure foreign object damage tests.
Background
During takeoff, landing or near-ground flight of an airplane/helicopter, gravel, stone or metal objects on a runway or the ground are often sucked into an aircraft engine flow channel along with strong airflow, and then collide with a fan/compressor blade rotating at high speed to form hard object impact damage (or foreign object damage FOD), which causes high-cycle fatigue damage of the engine blade at low weight and directly breaks the blade at high weight.
The severity degree of foreign object damage often depends on the shape and size of a foreign object sucked by an engine, but the complicated field environment (especially for a helicopter engine) causes the randomness of the shape and size of the foreign object sucked by an aircraft engine to be large, and after a foreign object damage event occurs, an engineer can only presume the material, the shape and the size of a sucked hard object according to the damage shape and the severity degree. In order to fully understand the influence of foreign object damage possibly generated by an external field on the structural durability performance such as high cycle fatigue of the blade, engineering personnel need to artificially create hard object impact damage. Although the test of sucking foreign objects by a real engine can absolutely and truly reproduce the damage of the foreign objects, the test process is uncontrollable and extremely high in cost. Therefore, simulating the real damage of the external field under the laboratory condition is particularly important for designing and maintaining and evaluating the durability of the blade structure after the damage of the object.
Therefore, a light gas gun test device (such as a low-speed light gas gun impact test device in the patent CN 201710896598.0) is invented and used for simulating foreign object damage under laboratory conditions. In order to simulate the foreign object damage of the outfield diversity, the simulated impact test needs to adopt simulated foreign objects of different materials, different sizes and different shapes to impact a test piece in different flight attitudes, which puts requirements on the use compatibility and the diversity of the light gas cannon. Meanwhile, in order to ensure the stability and repeatability of the impact test, the disturbance of the flying posture of the projectile caused by the separation of the projectile support and the projectile gradually becomes an unacceptable situation for engineers. Still adopt single circular bore cross-section gun barrel and the foreign object of bullet support's mode totally compatible variety in the engineering for a long time also can not effectively prevent the bullet support from carrying out the influence of flight gesture when breaking away from to the shot, if need carry out different foreign objects in bigger shape/size range and carry out impact damage analogue test then need newly set up many sets of light gas big gun test device or carry out the gun barrel and change the transformation, not only need a large amount of test spaces, need extra cost moreover.
Disclosure of Invention
The invention aims to provide a light gas gun test device for in-situ switching of a rotatable gun barrel, which aims to solve the problems of influence of a projectile support on the flight attitude of a projectile and the requirement of an impact test on the diversity of the postures of the gun barrel and the projectile in a foreign object damage simulation test.
In order to achieve the purpose, the invention adopts the technical scheme that:
the utility model provides a normal position switches light gas big gun test device of rotatable barrel, includes that many barrel ring supports, barrel cluster, bullet loading mouth head, export speed test head and base, wherein:
the multi-gun-barrel annular support comprises a square bracket and a chuck, the square bracket is fixed on the base, and the chuck is arranged in the square bracket;
the gun barrel cluster comprises a plurality of cylindrical gun barrels, and the cylindrical gun barrels are respectively and independently arranged in the chuck and can independently rotate relative to the chuck;
the loading port end socket is connected with an energy storage tank and arranged at the inlet of the cylindrical gun barrel;
the outlet speed measuring seal head is arranged at the outlet of the cylindrical gun barrel, and the outlet speed measuring seal head is connected with a laser speed measuring system.
The chuck is provided with a plurality of holes for the cylindrical gun barrel to pass through, the inner wall of each hole is uniformly provided with three clamping blocks and a spring, one end of the spring is contacted with the clamping blocks, and the other end of the spring is contacted with the inner wall of the hole.
The chuck is circular, and its circumference is provided with a plurality of constant head tanks, is provided with a locating hole on the square support, and a constant head tank of chuck corresponds with the locating hole of square support to through inserting the pin location.
The square support is composed of two semicircular parts, and two sides of the two semicircular parts are fixedly connected through lifting screws.
The loading port end socket is a cylindrical internal thread end socket, and a cylindrical internal and external thread gasket is arranged between the loading port end socket and the cylindrical gun barrel.
The export is tested the speed the head and is cylindrical, and has the internal thread, and two square penetrability breachs have been seted up to its lateral wall, and the export is tested the speed and is provided with cylindrical interior external screw thread gasket between head and the cylindrical gun barrel.
The cross sections of the bores of the cylindrical gun barrels are different in shape, inner diameter and outer diameter;
the shapes of the bore sections of the cylindrical gun barrels comprise a triangle, an ellipse and a square.
Has the advantages that: the invention effectively solves the problems of the influence of the projectile support on the flight attitude of the projectile in the foreign object damage simulation test and the requirements of the impact test on the diversity of the gun barrel and the diversity of the attitude of the projectile. The shot is directly loaded for impact, so that the influence of the projectile support on the flight attitude of the shot is avoided, and the mode of rotatably replacing the gun barrel has the advantages of space saving, component assembly reduction and simplicity in operation; the independent rotating device supported by the gun barrel can be used for better facilitating the adjustment of the impact form and the projectile attitude of a tester, so that the welding non-adjustability is prevented; the positioning pin is adopted for fixing, so that the processing cost can be saved to the greatest extent, the use is convenient, and the positioning is accurate.
Drawings
FIG. 1 is a schematic structural diagram of a light gas gun test device for in-situ switching of a rotatable gun barrel according to the present invention;
FIG. 2 is a schematic structural view of a loading port end socket;
FIG. 3 is a schematic view of the chuck;
FIG. 4 is a front view of a light gas gun test apparatus of the present invention in which a rotatable gun tube is switched in situ;
FIG. 5 is a schematic view of direct loading of a projectile;
the symbols in the figures are as follows:
1-outlet speed measuring end socket, 2-circular chuck, 3-base, 4-pin, 5-lifting bolt, 6-square support, 7-gun barrel cluster, 8-loading port end socket, 9-energy storage tank, 10-cylindrical gasket, 11-fixture block, 12-spring, 13-pin positioning groove, 14-triangular section gun barrel, 15-elliptical section gun barrel and 16-square section gun barrel.
Detailed Description
The invention is further explained below with reference to the drawings.
As shown in fig. 1, the light gas gun test device for in-situ switching of rotatable gun barrels of the invention comprises a multi-gun barrel annular support, a gun barrel cluster, a loading port end enclosure, an outlet speed measuring end enclosure and a base, wherein:
the multi-gun-barrel annular support comprises a square support 6 and a chuck 2, the square support 6 is fixed on a base 3, the chuck 2 is arranged in the square support 6, and lubricating oil is used for lubricating parts;
the gun barrel cluster 7 comprises a plurality of cylindrical gun barrels, the cylindrical gun barrels are respectively and independently arranged in the chuck 2 and can independently rotate relative to the chuck 2, and the cross sections of the gun bores of the cylindrical gun barrels are different in shape, inner diameter and outer diameter;
the loading port end socket 8 is connected with an energy storage tank 9 and arranged at the inlet of the cylindrical gun barrel;
the outlet speed measuring seal head 1 is arranged at the outlet of the cylindrical gun barrel, and the outlet speed measuring seal head 1 is connected with a laser speed measuring system.
As shown in fig. 2, the loading port end enclosure 8 is a cylindrical internal thread end enclosure, a cylindrical internal and external thread gasket 10 is arranged between the loading port end enclosure and the cylindrical gun barrel, and the loading port end enclosure 8 can be compatible with gun barrels with different internal and external diameters.
The head 1 that tests the speed of export is cylindrical, and has the internal thread, and two square penetrability breachs have been seted up to its lateral wall, and the export tests the speed and is provided with cylindrical internal and external screw thread gasket 10 between head 1 and the cylindrical gun barrel, and the export tests the speed the gun barrel of head 1 can compatible different internal and external diameters.
As shown in fig. 3, the chuck 2 is provided with a plurality of holes for the cylindrical barrel to pass through, three blocks 11 and springs 12 are uniformly arranged on the inner wall of each hole, one end of each spring 12 contacts with the block 11, and the other end contacts with the inner wall of the hole. The chuck 2 can be three-point positioned by the fixture blocks 11 and the springs 12, can be compatible with gun barrels with different inner and outer diameters, and can enable each gun barrel to independently rotate.
The chuck 2 is circular, and its circumference is provided with a plurality of constant head tanks 13, is provided with a locating hole on the square support 6, and a constant head tank 13 of chuck 2 corresponds with the locating hole of square support 6 to fix a position through inserting pin 4.
The square bracket 6 is composed of two semicircular components, and two sides of the two semicircular components are fixedly connected through a hoisting screw 5.
As shown in fig. 5, the bore cross-sectional shapes of the plurality of cylindrical barrels include triangular, elliptical, square, and the like.
The present invention will be further described with reference to the following examples.
Examples
This example shows the case where a foreign object damage simulation test is performed and gun barrels are switched.
Before the test is started, the chuck 2 is arranged on the square support 6, and then all gun barrels required by the test are arranged on the circular chuck 2 and are axially fixed by the fixture blocks 11 which are distributed in a regular triangle; and screwing the hoisting bolt 5 to fix the circular chuck 2.
When in use, the pin 4 is taken away, the hoisting bolt 5 is unscrewed, the circular chuck 2 is rotated, and the required gun barrel is fixed in the circular chuck pin positioning groove 13 by the pin 4 after being rotated to the lowest part; the charging opening compatible end socket 8 and the gasket 10 are connected with the energy storage tank 9; the outlet speed measuring end socket 1 is connected with a laser speed measuring system, and whether the laser speed measuring system can work reliably or not is judged; putting down the protective cover, pressing down a solenoid valve switch at a remote place after the air pressure of the energy storage tank reaches a set value, performing air-firing operation, and removing air in the energy storage tank and foreign matters in the gun barrel; opening the protective cover, and fixing the test piece by using a clamp according to the requirements of the experimental scheme on the impact angle, the position and the like; putting down the protective cover to ensure that the protective cover completely wraps the test piece and prevent the projectile from flying out to hurt the tester; putting the shot into a shot tube loading opening 8, and screwing a compatible seal head of the loading opening; when the air pressure of the energy storage tank reaches a set value, closing a switch of the air storage tank; the tester avoids, and opens the electromagnetic valve switch at a remote place to implement the test.
When the gun barrel is switched in the midway of the test, the loading port end socket 8 is screwed off, the outlet speed measuring end socket 1 is screwed off, the pin 4 is taken down, and the lifting screw 5 is unscrewed, so that the used gun barrel is positioned to the lowest part by the pin 4 in the circular chuck pin positioning groove 13, then the lifting screw 5 is screwed, the loading port compatible end socket 8 is screwed on, and the outlet speed measuring end socket 1 is screwed on, thus completing the gun barrel switching.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (8)
1. The utility model provides a light gas big gun test device of rotatable gun barrel is switched to normal position which characterized in that: including many gun pipes annular support, gun pipe cluster, bullet loading mouth head, export seal and the base of testing the speed, wherein:
the multi-gun-barrel annular support comprises a square support (6) and a chuck (2), the square support (6) is fixed on the base (3), and the chuck (2) is arranged in the square support (6);
the gun barrel cluster (7) comprises a plurality of cylindrical gun barrels, and the cylindrical gun barrels are respectively and independently arranged in the chuck (2) and can independently rotate relative to the chuck (2);
the loading port end enclosure (8) is connected with an energy storage tank (9) and arranged at the inlet of the cylindrical gun barrel;
the outlet speed measuring seal head (1) is arranged at the outlet of the cylindrical gun barrel, and the outlet speed measuring seal head (1) is connected with a laser speed measuring system.
2. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the chuck is characterized in that a plurality of holes for the cylindrical gun barrel to pass through are formed in the chuck (2), three clamping blocks (11) and springs (12) are uniformly arranged on the inner wall of each hole, one end of each spring (12) is in contact with one clamping block (11), and the other end of each spring is in contact with the inner wall of each hole.
3. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the chuck (2) is circular, a plurality of positioning grooves (13) are circumferentially arranged on the chuck, a positioning hole is formed in the square support (6), and one positioning groove (13) of the chuck (2) corresponds to the positioning hole of the square support (6) and is positioned by inserting the pin (4).
4. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the square support (6) is composed of two semicircular components, and two sides of the two semicircular components are fixedly connected through a hoisting screw (5).
5. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the loading port end socket (8) is a cylindrical internal thread end socket, and a cylindrical internal and external thread gasket (10) is arranged between the loading port end socket and the cylindrical gun barrel.
6. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the export is tested the speed head (1) and is cylindrical, and has the internal thread, and two square penetrability breachs have been seted up to its lateral wall, and the export is tested the speed and is provided with cylindrical interior external screw thread gasket (10) between head (1) and the cylindrical gun barrel.
7. The in-situ switchable rotatable barrel light gas gun test device of claim 1, wherein: the plurality of cylindrical gun barrels have different bore cross-sectional shapes, different inner diameters and different outer diameters.
8. The in-situ switchable rotatable barrel light gas gun test device of claim 7, wherein: the shapes of the bore sections of the cylindrical gun barrels comprise a triangle, an ellipse and a square.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110231511.4A CN113176156B (en) | 2021-03-02 | 2021-03-02 | Light gas gun test device capable of switching rotatable gun barrel in situ |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110231511.4A CN113176156B (en) | 2021-03-02 | 2021-03-02 | Light gas gun test device capable of switching rotatable gun barrel in situ |
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| CN113176156A true CN113176156A (en) | 2021-07-27 |
| CN113176156B CN113176156B (en) | 2022-12-23 |
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| CN114858396A (en) * | 2022-07-04 | 2022-08-05 | 中国飞机强度研究所 | Airplane component high-speed impact test device and method based on multi-caliber launching tube |
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| CN113176156B (en) | 2022-12-23 |
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