Jacking and quick-removing device for centering test of aircraft nose landing gear and its application method

Abstract

The invention discloses a jacking quick-withdrawing device for an automatic restoration test of an airplane nose landing gear and a use method thereof. The jacking quick-withdrawing device includes anair cylinder (21); the air cylinder is arranged on a workbench (25) in a reversed manner through a buffer spring (20); a piston rod of the air cylinder stretches out of and passes through the bufferspring and the workbench and is fixedly connected to a working horizontal plane (26); a rodless cavity (C) of the air cylinder is connected to a first working opening (A) of a reversing control valve(17); a rod cavity (D) of the air cylinder is directly connected to a second working opening (B) of the reversing control valve; an air bottle (13) is connected to an air inlet (P) of the reversing control valve via a reducing valve (15); and an air returning opening (T) of the reversing control valve communicates with atmosphere directly. When the reversing control valve is in a jacking state, air enters the rodless cavity of the air cylinder, the rod cavity discharges the air, and the air cylinder moves upward; and when the reversing control valve is in a quick-withdrawing state, air entersthe rod cavity of the air cylinder, the rodless cavity discharges the air, and the air cylinder moves downward.

Description

technical field [0001] The invention relates to a detection device for the front landing gear of an aircraft, in particular to a jacking and quick-removing device for the centering test of the front landing gear of an aircraft and its application method. Background technique [0002] The automatic centering of the nose landing gear of the aircraft refers to the process that the nose landing gear of the aircraft rotates to the required angle value after being retracted, and then automatically returns to the original position. The automatic centering function of the aircraft nose landing gear is an important verification function in the factory acceptance test of the nose landing gear, and the authenticity and accuracy of detecting the centering time of the landing gear is particularly important. At present, the method commonly used in China is to manually lift the piston rod of the front landing gear to the required compression position through a hydraulic jack, then manually...

AI Technical Summary

Problems solved by technology

[0003] The hydraulic jack structure has good stability when lifting the nose landing gear. However, in view of the large air pressure in the buffer chamber of the nose landing gear and the short return time, the following factors will restrict the test when the hydraulic jack is used for pressure relief. The accuracy of itself: when the hydraulic jack is used, the reverse air pressure generated by the landing gear acts on the hydraulic jack after manually opening the shut-off valve 8, and the oil in the large hydraulic cylinder 11 needs to pass through figure 1 The pipeline 10 and pipeline 7 in the pipeline return to the fuel tank 5; however, there is no rapid evacuation structure after the hydraulic jack releases pressure, the oil returns from the rodless cavity, and the pipeline is limited by the small structural size, etc., resulting in a large oil return resistance; On the contrary, the extension speed of the landing gear is very fast, so the time measurement of the automatic centering of the nose landing gear will be prolonged, which may cause the centering test of the nose landing gear to fail to meet the design requirements under certain circumstances; When the hydraulic jack performs the centering test of the nose landing gear, even if the centering test is within the scope of the design requirements, the reverse resistance factor will be introduced due to the poor oil return of the hydraulic jack, so that the centering time of the nose landing gear will not be truly and effectively determined. verify

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