Tool for buoyancy test of aircraft seat cushion

Abstract

The utility model relates to the field of buoyancy test, and particularly discloses a tool for buoyancy test of an aircraft seat cushion, which comprises a water tank and a positioning support arranged at the top of the water tank, and a force measuring mechanism mounted on the positioning support. The force measuring mechanism is connected with a clamping mechanism, and the clamping mechanism is used for clamping the aircraft cushion and placing the aircraft cushion in the water tank; the force measuring mechanism and the clamping mechanism are both perpendicular to the positioning support. A ball linear bearing is installed on the positioning support and is perpendicular to the positioning support. The ball linear bearing is connected with the clamping mechanism in a sliding mode, and the clamping mechanism does linear motion along the ball linear bearing. The buoyancy measuring device can accurately measure the buoyancy of the aircraft seat cushion.

Description

Technical Field

[0001] The utility model relates to the technical field of buoyancy testing, in particular to a tool used for buoyancy testing of aircraft seat cushions. Background Art

[0002] The existing internationally accepted civil aircraft design specifications have special technical standards (TSO) and mechanical requirements for seats and their component cushions, safety belts, etc. If the seat cushion is required to have a floating function, the cushion must be tested for its floating performance in accordance with the floating cushion requirements in the civil aviation technical standards (TSO); it can be seen from the seat cushion floating test standards FAA-TSO-C72c and CAAC-CTSO-C72c that, on the one hand, the test water temperature for the floating of aircraft cushions is required to be about 85 degrees Fahrenheit, or about 29.4 degrees Celsius; on the other hand, the aircraft cushion must be submerged in water to a depth of at least 24 inches and measured continuously for several hours.

[0003] The existing standards and specifications have clear requirements for test parameters and technical indicators. At the same time, according to relevant standards and specifications, the prior art also discloses a device for measuring the buoyancy of aircraft seat cushions, such as the patent with patent application number CN201811173958.5. The device specifically uses a fixed pulley to pull the seat cushion through a pull rope, and drags the seat cushion into the water. The buoyancy of a general seat cushion in water is often between 14 and 28 pounds. In this way, the buoyancy of the seat cushion is large and it is easy to generate a large friction force at the fixed pulley, resulting in the measurement result displayed by the high-precision digital dynamometer being often smaller than the actual buoyancy. Secondly, after the seat cushion is pulled into the water by a pull rope, the seat cushion is very easy to tilt due to uneven buoyancy, which does not meet the measurement requirements. Utility Model Content

[0004] In order to solve the problem of inaccurate measurement of the buoyancy of aircraft seat cushions at present, an embodiment of the utility model provides a tool for testing the buoyancy of aircraft seat cushions.

[0005] The embodiment of the utility model adopts the following technical scheme: a tool for testing the buoyancy of an aircraft seat cushion, comprising a water tank, and also comprising a positioning bracket provided on the top of the water tank, on which a force measuring mechanism is installed; the force measuring mechanism is connected to a clamping mechanism, which is used to clamp the aircraft seat cushion and place the aircraft seat cushion in the water tank; the force measuring mechanism and the clamping mechanism are both arranged vertically to the positioning bracket; a ball linear bearing is installed on the positioning bracket, and the ball linear bearing is perpendicular to the positioning bracket; the ball linear bearing is slidably connected to the clamping mechanism, and the clamping mechanism performs linear motion along the ball linear bearing.

[0006] Beneficial effects: Compared with the prior art, this solution sets a ball linear bearing perpendicular to the positioning bracket on the positioning bracket, and the ball linear bearing is slidably connected to the clamping mechanism, and the clamping mechanism performs linear motion, so that the clamping mechanism can directly measure the buoyancy of the aircraft seat cushion at different depths when clamping the aircraft seat cushion for testing, instead of measuring the component forces of the buoyancy of the aircraft seat cushion in different directions, which can improve the accuracy of the measurement. Secondly, the force measuring mechanism is set vertically to the positioning bracket, and the buoyancy of the aircraft seat cushion can be directly obtained in one direction, meeting the measurement requirements.

[0007] Preferably, the force measuring mechanism comprises a support frame and a force gauge, the support frame is fixedly mounted on the positioning frame, and the force gauge is connected to the support frame; the force measuring direction of the force gauge is arranged perpendicular to the positioning frame.

[0008] Beneficial effect: The dynamometer is supported by the support frame, so that the dynamometer can always remain perpendicular to the positioning bracket during testing, making the test more stable.

[0009] Preferably, the clamping mechanism includes a sliding rod, a clamping claw, a clamping claw seat, a clamping claw baffle and a locking piece; the force measuring mechanism is connected to the sliding rod, and the sliding rod is slidably connected to the ball linear bearing; the sliding rod is fixedly mounted on the clamping claw seat, and the clamping claw seat is away from the ball linear bearing; the clamping claw is connected to the clamping claw seat through a locking piece, and the locking piece is used to lock / unlock the swinging state of the clamping claw, and the clamping claw is close to the sliding rod; the clamping claw baffle is fixedly mounted on the clamping claw and away from the sliding rod; the force measuring mechanism is connected to the sliding rod and away from the clamping claw.

[0010] Beneficial effects: The clamping claws of the clamping mechanism clamp the aircraft seat cushion to ensure that the seat cushion will not tilt in the water; at the same time, a clamping claw baffle is provided on the clamping claw to prevent the seat cushion from shifting underwater. In addition, the swing state of the clamping claw is unlocked by the locking member, and the swing amplitude of the clamping claw can be adjusted accordingly according to the test needs.

[0011] Preferably, the locking member comprises a first bolt, and the clamping claw and the clamping claw seat are connected by the first bolt.

[0012] Beneficial effect: The locking piece can lock the clamping claw when opening and retracting, making it convenient to use and store.

[0013] Preferably, the clamping mechanism further includes a limiting assembly, the limiting assembly includes a limiting flange and a second bolt, the limiting flange is connected to the slide rod via the second bolt, and the limiting flange is located in the middle of the slide rod.

[0014] Beneficial effect: The limit flange is used to adjust the depth of the clamping mechanism entering the water. After the water immersion depth reaches the requirement, the flange can be locked by the second bolt to ensure that the clamping mechanism is always within the required depth range.

[0015] Preferably, there are four clamping claws in total, which together form a cross claw structure.

[0016] Beneficial effects: The cross claws can apply force evenly from four directions, making the aircraft seat cushion more stable during the clamping process, reducing vibration and displacement, and improving measurement accuracy. The cross claws can adapt to aircraft seat cushions of different shapes and sizes, and can be used to clamp the common aircraft seat cushions on the market.

[0017] Preferably, the clamping claw is 230 mm in length.

[0018] Beneficial effect: When the length of the clamping claw is less than 230 mm, the plane area of ​​the aircraft seat cushion is likely to be larger than the plane area of ​​the clamping claw, so that the aircraft seat cushion cannot be clamped by the clamping claw. When the length of the clamping claw is greater than 230 mm, not only the overall volume of the clamping mechanism is heavy, it is difficult to manually grasp the clamping mechanism for the corresponding buoyancy test; at the same time, the clamping claw baffle is difficult to play its role in preventing the aircraft seat cushion from shifting.

[0019] Preferably, the length of the sliding rod is 750 mm-780 mm.

[0020] Beneficial effect: The slide bar is 605mm-615mm, which can not only put the aircraft seat cushion into different depths underwater, and the depth can meet the measurement requirements, but also can maximize the reduction of the weight of the clamping mechanism.

[0021] Preferably, the sliding rod is an aluminum tube.

[0022] Beneficial effect: A dense aluminum oxide film is naturally formed on the aluminum surface, which can effectively prevent the aluminum tube from being oxidized by oxygen in the air and water, thus having good corrosion resistance and being suitable for testing in water.

[0023] Preferably, a plurality of first through holes are formed on the clamping claw baffle.

[0024] Beneficial effect: Providing the first through hole can effectively reduce the weight of the clamping mechanism and reduce the influence of the clamping mechanism on buoyancy during the test.

[0025] Preferably, a plurality of second through holes are formed on the clamping claw baffle.

[0026] Beneficial effect: Providing the second through hole can effectively reduce the weight of the clamping mechanism and reduce the influence of the clamping mechanism on buoyancy during the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic structural diagram of a tool for an aircraft seat cushion floating test according to an embodiment of the present invention;

[0028] Figure 2A top view of a water tank, a positioning bracket and a ball linear bearing of an embodiment;

[0029] Figure 3 Schematic diagram of the structure of the clamping mechanism of the embodiment. DETAILED DESCRIPTION

[0030] The reference numerals in the drawings of the specification include:

[0031] Sliding rod 1, clamping claw 21, clamping claw seat 22, second through hole 221, clamping claw baffle 3, first through hole 31, first bolt 4, dynamometer 51, support frame 52, positioning bracket 6, ball linear bearing 7, water tank 8, limit flange 9, second bolt 10, water surface A.

[0032] Example

[0033] This embodiment is basically Figure 1 As shown, a tool for the floating test of an aircraft seat cushion includes a water tank 8, a clamping mechanism, a force measuring mechanism and a positioning bracket 6. Figure 1 and 2 As shown, the positioning bracket 6 includes a plurality of beams. The positioning bracket 6 can be fixedly installed on the top of the water tank 8 by welding. A ball linear bearing 7 can be fixedly installed between the two beams by bolts. The ball linear bearing 7 is hollow cylindrical and perpendicular to the horizontal plane. When the bearing is well lubricated, the friction resistance is negligible and will not affect the buoyancy measurement. The ball linear bearing 7 is perpendicular to the positioning bracket 6.

[0034] The force measuring mechanism includes a support frame 52 and a force gauge 51. The support frame 52 can be fixedly mounted on the positioning bracket 6 by welding. The force gauge 51 can be mounted on the support frame 52 by detachable or fixed means. This is a conventional arrangement of those skilled in the art in the art. Figure 1 As shown, the dynamometer 51 is along the y-axis direction, and the horizontal plane is the plane formed by the x-axis and the z-axis. The positioning bracket 6 is parallel to the horizontal plane, the dynamometer 51 is perpendicular to the horizontal plane, and the dynamometer 51 is parallel to the ball linear bearing 7.

[0035] like Figure 3As shown, the clamping mechanism includes a slide bar 1, four clamping claws 21, a clamping claw seat 22, eight clamping claw baffles 3, a limit assembly and a locking member. The top of the dynamometer 51 and the slide bar 1 can be detachably connected. The limit assembly includes a limit flange 9 and a second bolt 10. The limit flange 9 is connected to the slide bar 1 through the second bolt 10, and the limit flange 9 is not less than 610 mm away from the clamping claw seat 22. The slide bar 1 matches the size of the inner ring of the ball linear bearing 7. The slide bar 1 passes through the inner ring of the ball linear bearing 7 and is slidably connected to the ball linear bearing 7, that is, the slide bar 1 can make a linear motion along the hollow direction of the ball linear bearing 7. The clamping claw seat 22 is fixedly installed at the bottom of the slide bar 1. The clamping claw seat 22 is connected to one clamping claw 21 through two locking members. The four clamping claws 21 are all connected to the clamping claw seat 22, and every two adjacent clamping claws 21 are arranged vertically, so that the aircraft seat cushion can be held more stably through this "cross" structure. In this embodiment, the locking member is a first bolt 4, and there are a total of 8 first bolts 4. By loosening the first bolt 4, the clamping claw 21 facing the positive direction of the z-axis can swing up and down in the zy direction with the center of the slide bar 1 as the origin. Figure 1 As shown, the length of the clamping claw 21 is b, b=230mm. The length of the slide bar 1 is a, 750mm≤a≤780mm. In this embodiment, there are 4 clamping claws 21, which together form a cross claw structure, and the slide bar 1 is an aluminum tube. The slide bar 1 is parallel to the dynamometer 51, and both are perpendicular to the horizontal plane.

[0036] like Figure 3 As shown, two clamping claw baffles 3 are fixedly installed on each clamping claw 21, and one clamping claw baffle 3 is fixedly installed on the right end and the lower end of the clamping claw 21 located in the positive direction of the x-axis, taking the center of the slide bar 1 as the origin. The clamping claw baffle 3 is provided with 8 or 6 first through holes 31. Specifically, the clamping claw baffles 3 located at the front, back, left and right sides are provided with 8 first through holes 31, and the clamping claw baffle 3 located at the bottom is provided with 6 first through holes 31. The thickness of the clamping claw seat 22 is 2-3mm. The second through hole 221 provided on the clamping claw seat 22 and the first through hole 31 provided on the clamping claw baffle 3 are both used for weight reduction.

[0037] like Figure 3 As shown, the second bolt 10 is located below the limiting flange 9 and is used to lock and loosen the limiting flange 9 on the slide bar 1. In this embodiment, the support frame 52 is an aluminum alloy rod.

[0038] How to use this embodiment

[0039] After the clamping mechanism, the force measuring mechanism and the positioning bracket 6 are assembled, the aircraft seat cushion is clamped by the clamping claw 21 and the clamping claw baffle 3, and the aircraft seat cushion is placed under the water surface A of the water tank 8 filled with water. Figure 1After the slide bar 1 is slidably connected to the ball linear bearing 7, the tester can hold the slide bar 1, and the specific holding position is above the ball linear bearing 7. The depth of the aircraft seat cushion under the water surface A can be controlled by the tester holding the slide bar 1 and moving it up and down in the ball linear bearing 7, thereby achieving the effect of measuring buoyancy.

[0040] Specifically, during the measurement, fill the box with an appropriate amount of water, turn on the heating, and reach the water level and temperature required by the experiment. Clamp the aircraft seat cushion in the cross claw, immerse the seat cushion in the test position 610mm underwater, and lock the limit flange by tightening the second bolt. Fix the dynamometer at the top of the support frame. The dynamometer is perpendicular to the horizontal plane, and it contacts the top of the support frame but does not generate any force. According to the relevant requirements of the buoyancy test, loosen the limit flange after soaking for a certain period of time, and slide the rod upward to push the dynamometer under the action of buoyancy to obtain a force value F1. Then record the force value at regular intervals until there is no large fluctuation in the force value for four consecutive times, and the final force value is counted as F2. After the measurement is completed, remove the seat cushion, hang the clamping mechanism on the dynamometer, place it in the underwater position just in the test, and record the underwater gravity F3 of the cross claw. The initial buoyancy of the seat cushion is calculated according to the formula 初 =F1+F3 ， Final buoyancy F 终 =F2+F3.

[0041] like Figure 3 As shown, after the test, the four clamping claws 21 can be put into a swinging state by loosening the first bolt 4, and the four clamping claws 21 can be erected to be almost perpendicular to the horizontal plane, that is, the xz plane, and then the clamping claws 21 can be tightened to achieve the purpose of foldability and portable carrying.

[0042] The beneficial effects of this embodiment

[0043] Compared with the prior art which uses a fixed pulley and a pull rope to test, due to the large buoyancy of the seat cushion, a large friction force will be generated at the fixed pulley, causing the dynamometer to display a measurement result that is often smaller than the actual buoyancy. At the same time, when using a pull rope, it is usually necessary to tie it with metal wire before it can be pulled into the water with the steel wire. After entering the water, due to the large buoyancy, the foam will have deep marks at the binding wire. In addition, during the test, the foam is prone to deformation due to the wire tying method, which affects the buoyancy measurement. Moreover, after the seat cushion is pulled into the water with a steel wire, the seat cushion is very likely to tilt due to uneven buoyancy, which does not meet the measurement requirements.

[0044] This embodiment is different. First, this embodiment uses the clamping mechanism to make vertical motion in the ball linear bearing 7, which is equivalent to linear motion. It is more accurate to directly measure the buoyancy in the vertical direction. What is not measured is the component of the buoyancy in other directions, which avoids the error caused by friction. The clamping claw baffle 3 is designed on the cross claw and the end of the cross claw to prevent the seat cushion from shifting and tilting underwater, which makes the measurement more accurate. The clamping claw baffle 3 can prevent the seat cushion from shifting and tilting underwater.

[0045] At the same time, by loosening the first bolt 4, the cross claw is in a swinging state. After the experiment is completed, the cross claw can be erected and the first bolt 4 can be tightened to achieve a foldable clamping mechanism for easy storage.

[0046] In the description of the present utility model, it should be noted that the terms "upper", "lower", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present utility model.

[0047] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] It should be understood that the term "and / or" used in this article is only a description of the same field of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0049] Although the subject matter has been described in language specific to structural features and / or methodological logical actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. On the contrary, the specific features and actions described above are merely example forms of implementing the claims.

[0050] The above is only an embodiment of the utility model. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the utility model before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, which will not affect the effect of the implementation of the utility model and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. A tool for testing the buoyancy of an aircraft seat cushion, comprising a water tank, characterized in that: It also includes a positioning bracket on the top of the water tank, on which a force measuring mechanism is installed; the force measuring mechanism is connected to a clamping mechanism, which is used to clamp the aircraft seat cushion and place the aircraft seat cushion in the water tank; the force measuring mechanism and the clamping mechanism are both arranged vertically to the positioning bracket; a ball linear bearing is installed on the positioning bracket, and the ball linear bearing is perpendicular to the positioning bracket; the ball linear bearing is slidably connected to the clamping mechanism, and the clamping mechanism performs linear motion along the ball linear bearing.

2. The tooling for aircraft seat cushion buoyancy testing according to claim 1, characterized in that: The force measuring mechanism comprises a support frame and a dynamometer. The support frame is fixedly mounted on the positioning frame, and the dynamometer is connected to the support frame. The force measuring direction of the dynamometer is arranged perpendicular to the positioning frame.

3. A tool for testing the buoyancy of an aircraft seat cushion according to claim 1 or 2, characterized in that: The clamping mechanism includes a sliding rod, a clamping claw, a clamping claw seat, a clamping claw baffle and a locking piece; the force measuring mechanism is connected to the sliding rod, and the sliding rod is slidably connected to the ball linear bearing; the sliding rod is fixedly installed on the clamping claw seat, and the clamping claw seat is far away from the ball linear bearing; the clamping claw is connected to the clamping claw seat through a locking piece, and the locking piece is used to lock / unlock the swinging state of the clamping claw, and the clamping claw is close to the sliding rod; the clamping claw baffle is fixedly installed on the clamping claw and away from the sliding rod; the force measuring mechanism is connected to the sliding rod and away from the clamping claw.

4. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: The locking member comprises a first bolt, and the clamping claw and the clamping claw seat are connected by the first bolt.

5. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: There are four clamping claws in total, which together form a cross claw structure.

6. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: The length of the clamping claw is 230 mm.

7. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: The length of the sliding rod is 750mm-780mm.

8. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: The slide bar is an aluminum tube.

9. The tooling for aircraft seat cushion buoyancy testing according to claim 3, characterized in that: The clamping claw baffle is provided with a plurality of first through holes.

10. The tool for testing the buoyancy of an aircraft seat cushion according to claim 3, characterized in that: The clamping claw baffle is provided with a plurality of second through holes.

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