Honeycomb type combined loading pad and method

Abstract

The invention discloses a honeycomb type combined loading pad and a method. Comprising a soft double-bottom honeycomb bag (1) and a U-shaped elastic cushion block (2), the soft double-bottom honeycomb bag (1) comprises an upper bonding surface (4) and a lower bonding surface (5) which are arranged in parallel, and a pair of honeycomb cavities (6) are transversely arranged between the upper bonding surface and the lower bonding surface; and two U-shaped arms of the U-shaped elastic cushion block (2) are respectively inserted into the corresponding honeycomb cavities (6). The device is high in universality and low in use cost.

Description

Technical Field

[0001] The invention relates to the technical field of aviation structure strength testing, and in particular to a honeycomb type combined loading pad and a method thereof. Background Art

[0002] In existing structural strength tests, unidirectional tensile load tape (canvas) or rubber-metal combined bidirectional loading modules are mainly used.

[0003] Tape can only apply tensile loads, especially for composite test pieces, compressive loads are applicable.

[0004] The loading pad of the rubber-metal combined bidirectional loading module is a special rubber block, that is, the rubber block is bonded to the bottom of the metal loading block, and then the special curved surface of the rubber block is pasted to the surface of the test piece. Finally, a new pasting process and adhesive are required for pasting. For this reason, there are the following defects: First, the rubber block needs to be processed with a curved surface to fit the surface shape of the test piece, which makes it not universal, resulting in high costs and difficult processing and pasting operations; second, when cleaning the rubber-metal combined bidirectional loading module, the cleaning agent cannot penetrate the rubber block and the metal block, and can only wait for them to fall off by themselves or be damaged and fall off, which does not have the characteristics of reuse, thereby causing material waste and increasing costs; third, the rubber-metal combined bidirectional loading module uses a new adhesive, which is not a universal adhesive and needs to be purchased in small batches, which is too expensive. Summary of the invention

[0005] The purpose of the present invention is to provide a honeycomb type combined loading pad and method. The present invention has strong versatility and low use cost.

[0006] Technical solution: A honeycomb type combined loading pad comprises a soft double-bottom honeycomb capsule and a U-shaped elastic pad; the soft double-bottom honeycomb capsule comprises a pair of upper bonding surfaces and lower bonding surfaces arranged in parallel, and a pair of honeycomb cavities are arranged in the transverse direction between the upper and lower bonding surfaces; two U-shaped arms of the U-shaped elastic pad are respectively inserted into corresponding honeycomb cavities.

[0007] In the aforementioned honeycomb type combined loading pad, after the two U-shaped arms are respectively inserted into the corresponding honeycomb cavities, the two U-shaped arms are detachably connected by a latch.

[0008] In the aforementioned honeycomb type combined loading pad, the cross section of the honeycomb cavity is a rectangular structure, and air-driving cavities are arranged on the four corners of the outer periphery of the honeycomb cavity.

[0009] In the aforementioned honeycomb combined loading pad, the soft double-bottom honeycomb bag is sewn with canvas.

[0010] A method for using the honeycomb combined loading pad as described above comprises bonding the upper bonding surface of the soft double-bottom honeycomb capsule to the bottom surface of the loading block, and bonding the lower bonding surface to the test piece; inserting the U-shaped elastic pad into the honeycomb cavity; and the loading block applies tension / pressure to the test piece through the honeycomb combined loading pad for testing.

[0011] In the method of using the aforementioned honeycomb combined loading pad, when the upper and lower bonding surfaces are respectively bonded to the bottom surface of the loading block and the test piece, a tool is used to squeeze the top and bottom surfaces of the honeycomb cavity and the air-expelling cavity.

[0012] In the method of using the aforementioned honeycomb combined loading pad, after the test is completed, the U-shaped elastic pad is removed, and the upper and lower bonding surfaces are soaked with a cleaning agent to separate the upper and lower bonding surfaces from the loading block and the test piece respectively.

[0013] In the method of using the aforementioned honeycomb composite loading pad, the adhesive used for the upper and lower bonding surfaces is FN305, and the cleaning agent is X-1 liquid cleaning agent.

[0014] Beneficial effects: The present invention designs a set of transition pads that can be used for bidirectional loading, which are used to connect the loading block and the test piece, so that it can adapt to the surface shape of the test piece, have universality, reuse characteristics, easy pasting / cleaning, low cost, and utilize existing pasting processes and materials.

[0015] The present invention utilizes Taibai canvas to make a double-bottom honeycomb capsule, wherein the upper bonding surface is used to stick a metal loading block, and the lower bonding surface is used to stick to the surface of a test piece. The soft double-bottom honeycomb capsule structure is easily deformed, and thus can better fit the surface of the test piece. At the same time, a universal adhesive is used for bonding, which has lower costs.

[0016] The soft double-bottom honeycomb bag of the present invention is composed of two large honeycomb cavities and six small air-driving cavities, wherein the two large honeycombs are used to fill the U-shaped elastic pads, which are detachable and have standardized structures (made into regular standard modules) compared with the existing bidirectional loading modules. After completing the bidirectional loading test, the U-shaped elastic pads can be taken out and used again, while the rubber pads of the bidirectional loading blocks in the past are molded and pasted to match the shape once and cannot be reused.

[0017] The present invention selects Taibai canvas to make a soft double-bottom honeycomb capsule, which not only has high tear strength and softness, but also has the inherent properties of cloth - easy to absorb liquid. The softness is convenient for operators to construct and fit test pieces. When removing the loading pad, the X-1 liquid cleaning agent is usually used to soak the soft double-bottom honeycomb capsule, which can soak and soften the FN305 adhesive layer for a long time, and finally wash off the bidirectional loading pad. This structure is easier to paste and clean.

[0018] The present invention utilizes universal adhesive materials, improves the reliability of pasting the loading pad, ensures the familiarity of the adhesive, and thus improves the construction quality of workers' operations (adhesive preparation, timing selection of gluing, etc.).

[0019] The design of the honeycomb combined loading pad of the present invention has promoted the further upgrading of the maturity of the bidirectional loading technology and its further extensive application in the strength test of aircraft models. Compared with the current unidirectional tensile load tape and bidirectional loading module (adhesive rubber loading pad), the utilization rate of the loading pad is further improved, the cost is reduced, and its reliability is guaranteed by using mature technology.

[0020] In the strength test of model development, the present invention not only improves the accuracy of load application, but also ensures the authenticity and safety of composite material specimen assessment. In particular, with the widespread application of composite materials in the fields of aviation and aerospace, the invention has more outstanding value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a diagram of the combination of honeycomb type loading pad and loading block;

[0022] Figure 2 It is a honeycomb type combined loading pad. DETAILED DESCRIPTION

[0023] Example 1. A honeycomb composite loading pad, see Figure 1 and Figure 2 , including a soft double-bottom honeycomb capsule 1 and a U-shaped elastic pad 2; the soft double-bottom honeycomb capsule 1 includes a pair of upper bonding surfaces 4 and lower bonding surfaces 5 arranged in parallel, and a pair of honeycomb cavities 6 are arranged laterally between the upper and lower bonding surfaces; the two U-shaped arms of the U-shaped elastic pad 2 are respectively inserted into the corresponding honeycomb cavities 6.

[0024] After the two U-shaped arms are respectively inserted into the corresponding honeycomb cavities 6 , the two U-shaped arms are detachably connected via the latch 3 .

[0025] The cross section of the honeycomb cavity 6 is a rectangular structure, and air-driving cavities 7 are provided on the outer corners of the honeycomb cavity 6 .

[0026] The aforementioned soft double-bottom honeycomb bag 1 is made by sewing canvas.

[0027] The method of using the aforementioned honeycomb combination loading pad is to bond the upper bonding surface 4 of the soft double-bottom honeycomb bag 1 to the bottom surface of the loading block 8, and bond the lower bonding surface 5 to the test piece; insert the U-shaped elastic pad 2 into the honeycomb cavity 6; the loading block 8 applies tension / pressure to the test piece through the honeycomb combination loading pad for testing.

[0028] When the upper and lower bonding surfaces are bonded to the bottom surface of the loading block 8 and the test piece respectively, a tool is used to squeeze the top and bottom surfaces of the honeycomb cavity 6 and the air-expelling cavity 7.

[0029] After the test is completed, the U-shaped elastic pad 2 is removed, and the upper and lower bonding surfaces 5 are soaked with a cleaning agent to separate the upper and lower bonding surfaces 5 from the loading block 8 and the test piece, respectively.

[0030] The adhesive used for the upper and lower bonding surfaces is FN305, and the cleaning agent is X-1 liquid cleaning agent.

[0031] The loading module of the present invention changes the pasting process and loading effect of the conventional adhesive tape and hard loading modules.

[0032] The honeycomb loading pad is mainly composed of a soft double-bottom honeycomb capsule 1, a U-shaped elastic pad 2 and a latch 3. The combined structure is shown in FIG. Figure 1 .

[0033] The soft double bottom honeycomb capsule 1 is mainly used to stick the metal loading block and the test piece (see Figure 1 ), whose honeycomb structure is mainly used to solve the problem of filling U-shaped elastic pads 2 (U-shaped sponge rubber blocks); when pasting the loading block and pasting it to the surface of the test piece, the air (internal bubbles) mixed in the adhesive liquid is driven out by operating the tool in the honeycomb cavity 6 and the air-expelling cavity 7, so that the soft double-bottom honeycomb capsule 1 is more densely and firmly pasted to the test piece and the loading block; the soft double-bottom honeycomb capsule 1 structure also has air permeability, which speeds up the drying process of the adhesive and shortens the construction time.

[0034] The U-shaped elastic pad 2 is mainly used to reduce the local extrusion of the composite material test piece, change the elastic modulus and thus reduce the influence on the internal force transmission of the test piece. Because the loading block with strong rigidity is directly attached to the test piece (especially the composite material), it may cause the local surface of the test piece to be excessively extruded when the load is applied; in addition, the loading block with strong rigidity is attached to the surface of the test piece and can be almost regarded as a whole. Its greater rigidity will change the path of the internal force transmission of the test piece or affect the shear force transmission diversion.

[0035] The latch is used to prevent the U-shaped elastic pad 2 from falling off during the test.

[0036] The pasting process is to first paste the soft double-bottom honeycomb capsule 1 onto the test piece, and then paste the loading block onto the soft double-bottom honeycomb capsule 1. After the adhesive is completely dry, the U-shaped elastic pad 2 is inserted into the soft double-bottom honeycomb capsule 1 and finally locked with a latch.

[0037] First, the aluminum loading block and the soft double-bottom honeycomb capsule 1 are glued together, which is convenient for the pasting process operation (convenient for expelling air after pasting and improving the uniformity of the bonding surface between the loading block and the double-bottom honeycomb capsule). At the same time, it is also beneficial to improve the drying efficiency after pasting, because the structural characteristics of the double-bottom honeycomb capsule have good air permeability, which further improves the reliability of the firm pasting of the aluminum module.

[0038] Then, after drying for one day, the aluminum loading block and the soft double-bottom honeycomb capsule 1 are integrally pasted to the surface of the test piece. In this way, the honeycomb cavity and the air-expelling cavity of the soft double-bottom honeycomb capsule 1 facilitate the implementation of the pasting process to expel air, and improve the drying efficiency (the honeycomb structure has good ventilation effect). In addition, the soft double-bottom honeycomb capsule 1 is made of canvas and has a honeycomb structure, which is very suitable for the curved surface characteristics of the test piece, and solves the defect that the bonding surface of the hard loading module does not fit.

[0039] Next, insert the U-shaped elastic pad 2 into the soft double-bottom honeycomb capsule 1 and lock it with the latch 3 to prevent the U-shaped elastic pad 2 from falling off. The compressible, deformable and soft properties of the U-shaped elastic pad 2 not only adapt to the characteristic surfaces of the test piece such as the curved surface and the flat surface, but also effectively protect the test piece during the force transmission process, avoiding local damage or deformation caused by local loading during the bidirectional loading (transmitting the bidirectional load to the test piece through the module).

[0040] Finally, complete Figure 1 After the structure is pasted as a whole, the bidirectional load transfer is perfectly realized. The key point is that the aluminum loading module, U-shaped elastic pad 2, latch 3, etc. can be disassembled, and its standardized structure can be reused many times, which greatly saves costs compared to the hard loading module. Compared with the tape, it realizes the bidirectional load transfer function.

Claims

1. A honeycomb composite loading pad, characterized in that: The invention comprises a soft double-bottom honeycomb capsule (1) and a U-shaped elastic pad (2); the soft double-bottom honeycomb capsule (1) comprises a pair of upper bonding surfaces (4) and lower bonding surfaces (5) arranged in parallel, and a pair of honeycomb cavities (6) are arranged in the transverse direction between the upper and lower bonding surfaces; and the two U-shaped arms of the U-shaped elastic pad (2) are respectively inserted into the corresponding honeycomb cavities (6).

2. The honeycomb composite loading pad according to claim 1, characterized in that: After the two U-shaped arms are respectively inserted into the corresponding honeycomb cavities (6), the two U-shaped arms are detachably connected via the latch (3).

3. The honeycomb composite loading pad according to claim 1, characterized in that: The cross section of the honeycomb cavity (6) is a rectangular structure, and air-driving cavities (7) are arranged on the outer corners of the honeycomb cavity (6).

4. The honeycomb composite loading pad according to claim 1, characterized in that: The soft double-bottom honeycomb bag (1) is made by sewing canvas.

5. A method for using the honeycomb composite loading pad according to any one of claims 1 to 4, characterized in that: The upper bonding surface (4) of the soft double-bottom honeycomb bag (1) is bonded to the bottom surface of the loading block (8), and the lower bonding surface (5) is bonded to the test piece; the U-shaped elastic pad (2) is inserted into the honeycomb cavity (6); the loading block (8) applies tension / pressure to the test piece via the honeycomb combined loading pad to perform the test.

6. The method for using the honeycomb type combined loading pad according to claim 5, characterized in that: When the upper and lower bonding surfaces are bonded to the bottom surface of the loading block (8) and the test piece respectively, a tool is used to squeeze the top and bottom surfaces of the honeycomb cavity (6) and the air-driving cavity (7).

7. The method for using the honeycomb composite loading pad according to claim 5, characterized in that: After the test is completed, the U-shaped elastic pad (2) is removed, and the upper and lower bonding surfaces (5) are soaked with a cleaning agent to separate the upper and lower bonding surfaces (5) from the loading block (8) and the test piece, respectively.

8. The method for using the honeycomb type combined loading pad according to claim 7, characterized in that: The adhesive used for the upper and lower bonding surfaces is FN305, and the cleaning agent is X-1 liquid cleaning agent.

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