Helicopter fuselage horizontal measurement point installation error elimination method

Abstract

The invention belongs to the technical field of helicopter horizontal measurement, and particularly relates to a helicopter fuselage horizontal measurement point installation error elimination method. Eight horizontal measurement points of the fuselage are symmetrically located on the two sides of the fuselage, and the other three horizontal measurement points of the fuselage are located on the Y0 axis of the bottom of the fuselage. Calibrating two determined horizontal measuring points on the electronic level meter and the subassembly fixture to obtain the positions of the other six horizontal measuring points; s2, bolt holes in the two Y0 axes of the bottom of the fuselage are determined on the subassembly fixture and marked as a mark point A and a mark point B, and a mark point C is obtained through fuselage calibration; through the method for eliminating the installation error of the horizontal measurement point, the installation precision of the horizontal measurement point on the fuselage is greatly improved, the installation error is eliminated, the precision of the measurement result of the horizontal measurement item is improved, and the reliability of the horizontal measurement result is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of helicopter level measurement, and in particular relates to a method for eliminating installation errors of helicopter fuselage level measurement points. Background Art

[0002] The purpose of helicopter leveling and calibration checks is to control the geometry of the fuselage during regular checks or after an accident based on the leveling and calibration points on the fuselage and tail boom. Leveling and calibration during the helicopter assembly phase is not a manufacturing control check, but a necessary process before the helicopter is put into use after final assembly. It mainly involves the installation and inspection of leveling and calibration points during the helicopter assembly phase, and the inspection results are recorded in the logbook as a reference value. If the tail boom needs to be replaced during subsequent use, the leveling and calibration points on the tail boom need to be leveled and calibrated.

[0003] The traditional domestic helicopter horizontal measurement points and calibration points are completed in the component assembly stage, and the installation accuracy is guaranteed by the assembly jig. After the main structure, tail structure and system installation are completed in the final assembly stage, horizontal measurement and calibration inspection are carried out. The inspection results include the errors in the component assembly stage, assembly errors in the final assembly stage and measurement errors. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for eliminating installation errors of horizontal measurement points of a helicopter fuselage, and the horizontal measurement and calibration are divided into two steps for implementation: two horizontal measurement points and two calibration points are implemented in the main structure sub-assembly stage, and the two horizontal measurement points are used as reference points for three points to determine a reference plane, and the two calibration points are used as reference points for two points to determine a calibration line; after the final assembly of the remaining horizontal measurement points and calibration points is completed, the two horizontal measurement points and two calibration points completed in the sub-assembly stage are used as the reference plane and the reference line, and the assembly errors are eliminated through horizontal measurement and calibration.

[0005] The present invention is implemented by adopting the following technical scheme.

[0006] A method for eliminating installation errors of horizontal measurement points on a helicopter fuselage, wherein there are eleven horizontal measurement points on the fuselage, eight of which are symmetrically located on both sides of the fuselage, and the remaining three are located on the Y0 axis at the bottom of the fuselage. The method comprises:

[0007] S1, determine two horizontal measurement points of the fuselage on the subassembly jig, and calibrate the positions of the remaining six horizontal measurement points by using an electronic level and the two horizontal measurement points determined on the subassembly jig;

[0008] S2, determine the bolt holes on the two Y0 axes at the bottom of the fuselage on the assembly jig, record them as marking point A and marking point B, and obtain marking point C through fuselage calibration.

[0009] Furthermore, the measurement points on the right side of the fuselage from the nose to the tail are marked points 2, 4, 6, and 8 respectively, and S1 is specifically:

[0010] S11: First, two horizontal measurement marks on the right side of the fuselage are determined on the assembly jig, and are recorded as mark point 2 and mark point 6;

[0011] S12: Arrange a first electronic level on the right side of the middle of the fuselage, 3-4 meters away from the fuselage, align the first electronic level with the marking point 2, and keep the aiming plane obtained in this way unchanged;

[0012] S13: using the first electronic level to aim at the plane and check and calibrate the mark point 4, adjusting the position of the mark point 4 on the fuselage so that the position of the mark point 4 on the aiming plane overlaps with the mark point 2, and installing the horizontal measurement mark of the mark point 4 on the fuselage;

[0013] S14: Determine the position of the marking point 8 on the fuselage in the manner of S13, and install the horizontal measurement mark of the marking point 8 on the fuselage.

[0014] Furthermore, the measurement points on the left side of the fuselage from the nose to the tail are marked points 1, 3, 5, and 7 respectively; S1 also includes:

[0015] S15, without losing the aiming point on the right side of the fuselage, determine a reference point, wherein the reference point and the aiming point on the right side of the fuselage are on the same horizontal plane, and the position of the reference point satisfies that when the aiming point is established on the left side of the fuselage, the reference point can be observed from the aiming point on the left side;

[0016] S16, keep the first electronic level unchanged on the right side of the fuselage, and locate the horizontal aiming point symmetrically on the left side of the fuselage;

[0017] S17, placing mark point 1 at a symmetrical position of mark point 2, adjusting the position of mark point 1 so as to align it with the aiming plane of the second electronic level, and installing a horizontal measurement mark of mark point 1 on the fuselage;

[0018] S18, determining the positions of the marking points 3, 5, and 7 on the fuselage according to the method of S17, and installing the horizontal measurement marks corresponding to the marking points on the fuselage.

[0019] Further, in S12, the first electronic level is placed on a first tripod.

[0020] Further, in S15, a second tripod is placed and leveled with the aiming point, and the center point of the upper surface of the second tripod is determined as a reference point.

[0021] Further, in S16, when locating the horizontal aiming point, the third tripod is placed at a position symmetrical to the first tripod, the second electronic level is placed on the third tripod, and the second electronic level is aligned with the reference point.

[0022] Furthermore, S2 is specifically:

[0023] S21, open two bolt holes on the Y0 axis of the fuselage bottom, marked as point A and point B, where point A is located on the Y0 axis of the fuselage and the frame in front of the landing gear compartment, and point B is located on the Y0 axis of the fuselage and the frame where the transition section and the tail beam meet;

[0024] S22, locate the first plumb line at mark point A, locate the second plumb line at mark point B. When the plumb lines are stable, tighten the thin line on the ground, make an extension line along the projections of the two plumb lines on the ground to the end of the tail beam, make a bolt hole on the projection of the tail beam with the thin line, and add a bolt. The surface center point of the bolt is mark point C.

[0025] The above-mentioned method for eliminating installation errors of horizontal measurement points will greatly improve the installation accuracy of the horizontal measurement points on the fuselage, eliminate installation errors, improve the accuracy of the measurement results of the horizontal measurement items, and ensure the reliability of the horizontal measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the positions of horizontal measurement points on a fuselage provided by an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of the arrangement position of the electronic level provided in an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of calibration of horizontal measurement mark points provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings.

[0030] The embodiment of the present invention provides a method for eliminating installation errors of horizontal measurement points on a helicopter fuselage. There are eleven horizontal measurement points on the fuselage, eight of which are symmetrically located on both sides of the fuselage, and the remaining three are located on the Y0 axis at the bottom of the fuselage. The method includes:

[0031] S1, determine two horizontal measurement points of the fuselage on the subassembly jig, and calibrate the positions of the remaining six horizontal measurement points by using an electronic level and the two horizontal measurement points determined on the subassembly jig;

[0032] S2, determine the bolt holes on the two Y0 axes at the bottom of the fuselage on the assembly jig, record them as marking point A and marking point B, and obtain marking point C through fuselage calibration.

[0033] The measurement points on the right side of the fuselage from the nose to the tail are marked points 2, 4, 6, and 8. S1 is specifically:

[0034] S11: First, two horizontal measurement marks on the right side of the fuselage are determined on the assembly jig, and are recorded as mark point 2 and mark point 6;

[0035] S12: Arrange a first electronic level on the right side of the middle of the fuselage, 3-4 meters away from the fuselage, align the first electronic level with the marking point 2, and keep the aiming plane obtained in this way unchanged;

[0036] S13: using the first electronic level to aim at the plane and check and calibrate the mark point 4, adjusting the position of the mark point 4 on the fuselage so that the position of the mark point 4 on the aiming plane overlaps with the mark point 2, and installing the horizontal measurement mark of the mark point 4 on the fuselage;

[0037] S14: Determine the position of the marking point 8 on the fuselage in the manner of S13, and install the horizontal measurement mark of the marking point 8 on the fuselage.

[0038] The measurement points on the left side of the fuselage from the nose to the tail are marked points 1, 3, 5, and 7; S1 also includes:

[0039] S15, without losing the aiming point on the right side of the fuselage, determine a reference point, wherein the reference point and the aiming point on the right side of the fuselage are on the same horizontal plane, and the position of the reference point satisfies that when the aiming point is established on the left side of the fuselage, the reference point can be observed from the aiming point on the left side;

[0040] S16, keep the first electronic level unchanged on the right side of the fuselage, and locate the horizontal aiming point symmetrically on the left side of the fuselage;

[0041] S17, placing mark point 1 at a symmetrical position of mark point 2, adjusting the position of mark point 1 so as to align it with the aiming plane of the second electronic level, and installing a horizontal measurement mark of mark point 1 on the fuselage;

[0042] S18, determining the positions of the marking points 3, 5, and 7 on the fuselage according to the method of S17, and installing the horizontal measurement marks corresponding to the marking points on the fuselage.

[0043] In S12, the first electronic level is placed on a first tripod.

[0044] In S15, a second tripod is placed and leveled with the aiming point, and the center point of the upper surface of the second tripod is determined as a reference point.

[0045] In S16, when locating the horizontal aiming point, the third tripod is placed at a position symmetrical to the first tripod, the second electronic level is placed on the third tripod, and the second electronic level is aligned with the reference point.

[0046] S2 is specifically:

[0047] S21, open two bolt holes on the Y0 axis of the fuselage bottom, marked as point A and point B, where point A is located on the Y0 axis of the fuselage and the frame in front of the landing gear compartment, and point B is located on the Y0 axis of the fuselage and the frame where the transition section and the tail beam meet;

[0048] S22, locate the first plumb line at mark point A, locate the second plumb line at mark point B. When the plumb lines are stable, tighten the thin line on the ground, make an extension line along the projections of the two plumb lines on the ground to the end of the tail beam, make a bolt hole on the projection of the tail beam with the thin line, and add a bolt. The surface center point of the bolt is mark point C.

[0049] Taking a medium-sized helicopter as an example, there are 8 horizontal measurement points on the fuselage, mainly located on both sides of the fuselage. Figure 1 .

[0050] Considering the large size of the whole machine, a slight deviation in the installation of the horizontal measurement points will lead to inaccurate final horizontal measurement results. The following fuselage horizontal measurement point installation calibration method is adopted: determine two fuselage horizontal measurement points and two bolt holes on the Y0 axis of the fuselage bottom (marking point A and marking point B) on the jig. Calibrate with an electronic level and the two horizontal measurement points determined on the jig to obtain the accurate positions of the remaining six horizontal measurement points. Determine the marking point C through fuselage calibration, which will greatly improve the installation accuracy of the fuselage horizontal measurement points.

[0051] A method for eliminating installation errors of horizontal measurement points of a helicopter fuselage according to the present invention comprises the following steps:

[0052] Step 1: Open two bolt holes A and B on the Y0 axis at the bottom of the fuselage;

[0053] Step 2: First determine the two horizontal measurement marks (2 and 6) on the right side of the fuselage on the structural assembly jig;

[0054] Step 3: Place an electronic level (on a tripod) on the right side of the middle of the fuselage, about 3-4 meters away from the fuselage, and align it with mark point 2 (see the specific location for details). Figure 2 ) Use an electronic level to accurately calibrate the level, and the aiming plane obtained in this way must be kept unchanged until the level measurement is completed.

[0055] Step 4: Use the electronic level to aim at the plane to check and calibrate mark point 4. Adjust the position of mark point 4 on the fuselage so that it overlaps with mark point 2 on the aiming plane until the displayed value stabilizes. Figure 3 , and install the horizontal measurement mark on the fuselage.

[0056] Step 5: Repeat Step 3-Step 4 to determine the position of mark point 8 on the fuselage and install the horizontal measurement mark on the fuselage.

[0057] Step 6: Without losing the aiming point, place the second tripod and align it with the aiming point (on the same horizontal plane as the aiming point), and mark it as a reference point. When the aiming point is established on the left side of the fuselage, the reference point can be observed from the aiming point.

[0058] Step 7: Keep the electronic level on the right side of the fuselage. Locate the horizontal aiming point at the symmetrical position on the left side and repeat step 3 to accurately calibrate the level.

[0059] Step 8: Place Mark 1 at the symmetrical position of Mark 2, adjust the position of Mark 1 so that it is aligned with the aiming plane, and install the horizontal measurement mark on the fuselage.

[0060] Step 9: Repeat step 8 to determine the positions of mark points 3, 5, and 7 on the fuselage, and install the horizontal measurement mark on the fuselage.

[0061] Step 10: Locate the first plumb line at mark point A, which is located on the Y0 axis of the fuselage and the frame in front of the landing gear compartment. Locate the second plumb line at mark point B, which is located on the Y0 axis of the fuselage and the docking frame of the transition section and the tail beam. When the plumb line is stable, tighten the thin line on the ground, and make an extension line along the projection of the two plumb lines on the ground to the end of the tail beam. Make an M5 bolt hole on the projection of the tail beam with the thin line, and add an M5 bolt to mark point C.

[0062] The above-mentioned method for eliminating installation errors of horizontal measurement points will greatly improve the installation accuracy of the horizontal measurement points on the fuselage, eliminate installation errors, improve the accuracy of the measurement results of the horizontal measurement items, and ensure the reliability of the horizontal measurement results.

Claims

1. A method for eliminating installation errors of horizontal measurement points on a helicopter fuselage, characterized in that: There are eleven fuselage horizontal measurement points, eight of which are symmetrically located on both sides of the fuselage, and the remaining three are located on the Y0 axis of the fuselage bottom. The method includes: S1, determine two horizontal measurement points of the fuselage on the subassembly jig, and calibrate the positions of the remaining six horizontal measurement points by using an electronic level and the two horizontal measurement points determined on the subassembly jig; S2, determine the bolt holes on the two Y0 axes at the bottom of the fuselage on the assembly jig, record them as marking point A and marking point B, and obtain marking point C through fuselage calibration.

2. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 1, characterized in that: The measurement points on the right side of the fuselage from the nose to the tail are marked points 2, 4, 6, and 8. S1 is specifically: S11: First, two horizontal measurement marks on the right side of the fuselage are determined on the assembly jig, and are recorded as mark point 2 and mark point 6; S12: Arrange a first electronic level on the right side of the middle of the fuselage, 3-4 meters away from the fuselage, align the first electronic level with the marking point 2, and keep the aiming plane obtained in this way unchanged; S13: using the first electronic level to aim at the plane and check and calibrate the mark point 4, adjusting the position of the mark point 4 on the fuselage so that the position of the mark point 4 on the aiming plane overlaps with the mark point 2, and installing the horizontal measurement mark of the mark point 4 on the fuselage; S14: Determine the position of the marking point 8 on the fuselage in the manner of S13, and install the horizontal measurement mark of the marking point 8 on the fuselage.

3. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 2, characterized in that: The measurement points on the left side of the fuselage from the nose to the tail are marked points 1, 3, 5, and 7; S1 also includes: S15, without losing the aiming point on the right side of the fuselage, determine a reference point, wherein the reference point and the aiming point on the right side of the fuselage are on the same horizontal plane, and the position of the reference point satisfies that when the aiming point is established on the left side of the fuselage, the reference point can be observed from the aiming point on the left side; S16, keep the first electronic level unchanged on the right side of the fuselage, and locate the horizontal aiming point symmetrically on the left side of the fuselage; S17, placing mark point 1 at a symmetrical position of mark point 2, adjusting the position of mark point 1 so as to align it with the aiming plane of the second electronic level, and installing a horizontal measurement mark of mark point 1 on the fuselage; S18, determining the positions of the marking points 3, 5, and 7 on the fuselage according to the method of S17, and installing the horizontal measurement marks corresponding to the marking points on the fuselage.

4. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 2, characterized in that: In S12, the first electronic level is placed on a first tripod.

5. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 3, characterized in that: In S15, a second tripod is placed and leveled with the aiming point, and the center point of the upper surface of the second tripod is determined as a reference point.

6. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 5, characterized in that: In S16, when locating the horizontal aiming point, the third tripod is placed at a position symmetrical to the first tripod, the second electronic level is placed on the third tripod, and the second electronic level is aligned with the reference point.

7. A method for eliminating installation errors of helicopter fuselage horizontal measurement points according to claim 1, characterized in that: S2 is specifically: S21, open two bolt holes on the Y0 axis of the fuselage bottom, marked as point A and point B, where point A is located on the Y0 axis of the fuselage and the frame in front of the landing gear compartment, and point B is located on the Y0 axis of the fuselage and the frame where the transition section and the tail beam meet; S22, locate the first plumb line at mark point A, locate the second plumb line at mark point B. When the plumb lines are stable, tighten the thin line on the ground, make an extension line along the projections of the two plumb lines on the ground to the end of the tail beam, make a bolt hole on the projection of the tail beam with the thin line, and add a bolt. The surface center point of the bolt is mark point C.

8. A helicopter, characterized in that: The helicopter adopts the method as described in any one of claims 1-7 to eliminate the installation error of the fuselage horizontal measurement point.

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