A helicopter main hub damper length adjustment measuring tool

Abstract

The utility model relates to a kind of helicopter main mast hub damper length adjustment measuring tools, including base, stand, sliding support, first vernier caliper and connecting crossbeam, the base both ends are vertically provided with stand, the stand upper end is vertically slidably provided with sliding support, the stand and sliding support are vertically provided with scale line on, the stand and sliding support constitute support unit, the height of stand relative to base can be determined by reading scale line, first vernier caliper and connecting crossbeam are horizontally provided between two support units, the height of sliding support and first vernier caliper can be changed by changing the fixed position of sliding support on stand, the utility model is by the base, stand, sliding support and is designed to large range support frame, break through the limitation that regular measuring tool cannot measure large-span of damper two end handle joint bearing center hole due to small range, satisfy the measurement demand of various models damper of helicopter.

Description

Technical Field

[0001] This utility model relates to the field of helicopter damper measurement technology, specifically a measuring tool for adjusting the length of a helicopter main rotor hub damper. Background Technology

[0002] During scheduled maintenance of the Z-10 helicopter, in accordance with maintenance recommendations, a detailed inspection of the main rotor hub damper is required every T-check (basic technical check) or 1000-hour cycle. If, during inspection, the radial clearance of the damper's shank bearing is found to exceed the specified value of 0.25mm, the shank bearing must be replaced. When replacing the shank bearing, the length of the damper assembly must be adjusted according to technical requirements, ensuring L = 555.8 ± 0.1mm.

[0003] During helicopter operation, each rotor blade generates a certain amount of shimmy due to its cyclic pitch-changing motion. If, during parts replacement, the thread extension length of the shank bearing exceeds the specified range, it will cause inconsistencies in the circumferential distance between the five rotor blade arms on the main rotor hub. This results in excessive vibration of the main rotor, and this vibration problem cannot be adjusted below the limit by adding counterweights. Ensuring consistent circumferential distance between the five rotor blade arms on the main rotor hub is essential to reduce the main rotor vibration.

[0004] However, in actual scheduled maintenance, this operation is difficult to perform accurately due to the large span of the center holes of the spur bearings at both ends of the damper. Commonly used measuring tools have limited ranges, and the center hole position is not level with the damper cylinder, making accurate measurement impossible. During actual maintenance, the length (L) values ​​of the five dampers often differ significantly when replacing the spur bearings. After installation, it is difficult to reduce vibration values ​​during helicopter cone and vibration adjustments. Furthermore, the circumferential clearance between each blade is uneven, as observed by a stroboscope, resulting in significant time and resource consumption. Therefore, we designed and manufactured a height-adjustable, large-range specialized measuring tool capable of measuring the length of various models of dampers for helicopters, with a measurement accuracy within 0.02 mm. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a measuring tool for adjusting the length of a helicopter main rotor hub damper, addressing the above-mentioned shortcomings.

[0006] To solve the above technical problems, the present invention adopts the following technical solution:

[0007] A measuring tool for adjusting the length of a helicopter main rotor hub damper includes a base, columns, a sliding support, a first vernier caliper, and a connecting beam. Columns are vertically mounted at both ends of the base, and a sliding support is vertically slidably mounted on the upper end of each column. Both the columns and the sliding support have vertically mounted scale lines. The columns and the sliding support form a support unit. The height of the column relative to the base can be determined by reading the scale lines. A first vernier caliper and a connecting beam are horizontally mounted between the two support units. The height of the sliding support and the first vernier caliper can be changed by altering the fixed position of the sliding support on the columns.

[0008] Furthermore, the sliding support is provided with fastening bolts for fixing the sliding support to the column, and the sliding support is a T-shaped part.

[0009] Furthermore, both the sliding support and the first vernier caliper are provided with corresponding positioning holes, and the inner side of the positioning holes is used to insert positioning pins to fix the sliding support and the first vernier caliper in place.

[0010] Furthermore, a slider is provided on one side of the sliding support for pushing the sliding support to move up and down.

[0011] Compared with the prior art, the present invention, by adopting the above technical solution, has the following advantages:

[0012] This invention overcomes the limitation of conventional measuring tools, which, due to their small measuring range, cannot measure the large span of the center holes of the shank bearings at both ends of the damper, by designing a large-range support frame consisting of a base, column, and sliding support. This meets the measurement needs of various models of dampers for helicopters. The column and sliding support integrate a second vernier caliper structure. Combined with the precise fit between the vernier caliper's main scale and the positioning hole, the measurement error is controlled within 0.02mm, effectively avoiding inconsistencies in the circumferential distance of the main rotor hub caused by damper length deviations. Specialized tools can quickly complete the measurement and adjustment of the damper length, avoiding repeated adjustments caused by large differences in the lengths of the five dampers in traditional methods, significantly shortening the adjustment time for helicopter cones and vibrations.

[0013] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0015] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0016] Figure 3 Top view of the length measurement of this utility model

[0017] Figure 4 This is a schematic diagram of the three-dimensional structure of the supporting unit.

[0018] The attached diagram lists the components represented by each number as follows:

[0019] 1. Base; 2. Column; 3. Sliding support; 4. First vernier caliper; 5. Connecting beam; 6. Second vernier caliper; 7. Fastening bolt; 8. Positioning hole; 9. Slider. Detailed Implementation

[0020] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0021] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] like Figure 1-4 As shown, a measuring tool for adjusting the length of a helicopter main rotor hub damper includes a base 1, a column 2, a sliding support 3, a first vernier caliper 4, and a connecting beam 5. The base 1 has columns 2 vertically arranged at both ends, and the sliding support 3 is vertically slidably arranged on the upper end of the column 2. Both the column 2 and the sliding support 3 have vertically arranged scale lines. The column 2 and the sliding support 3 form a support unit. The height of the column 2 relative to the base 1 can be determined by reading the scale lines. The first vernier caliper 4 and the connecting beam 5 are horizontally arranged between the two support units. The height of the sliding support 3 and the first vernier caliper 4 can be changed by changing the fixed position of the sliding support 3 on the column 2.

[0023] In one embodiment, the sliding support 3 is provided with fastening bolts 7 for fixing the sliding support 3 to the column 2, and the sliding support 3 is a T-shaped part.

[0024] In one embodiment, the sliding support 3 and the first vernier caliper 4 are respectively provided with positioning holes, and the inner side of the positioning hole 8 is used to insert a positioning pin to fix the sliding support 3 and the first vernier caliper 4 together.

[0025] In one embodiment, a slider 9 is provided on one side of the sliding support 3 for pushing the sliding support 3 to move up and down.

[0026] The working process of this utility model:

[0027] First, screw the two stubble bearings into both ends of the damper cylinder according to the approximate dimensions. Then, fix the damper assembly onto the damper adjuster fixture and use the fixture fixing bolts to adjust the stubble bearings at both ends of the damper to the same horizontal plane.

[0028] Unscrew the tooling fixing bolts and install two center hole measuring positioning pins on the shank bearings at both ends of the damper.

[0029] Place the measuring tool on one side of the special tooling, adjust the height of the left sliding support 3, and fix it with the fastening bolt 7.

[0030] Adjust the height of the right sliding support 3 to match the height reading on the left side, and then secure it with the fastening bolt 7.

[0031] Align the positioning hole 8 on the first vernier caliper 4 with the positioning post of the sliding support 3 and install the first vernier caliper 4. Then align the measuring reference surface of the first vernier caliper 4, i.e. the zero scale line, with the center line of the center hole positioning pin of the left-side shank bearing of the damper.

[0032] Slide the vernier on the first vernier caliper 4 to align it with the center line of the center hole locating pin of the right-side spherical bearing, and read the data.

[0033] If the length exceeds the specified value (L=555.8±0.1mm), then, depending on the actual length, screw in (shorten) or unscrew (extend) the threads of the spherical bearings with handles at both ends of the damper, and repeat the above steps until the length meets the standard requirements.

[0034] The above description provides examples of the preferred embodiments of this utility model. Any aspects not detailed herein are common knowledge to those skilled in the art. The scope of protection of this utility model is determined by the claims. Any equivalent modifications based on the technical teachings of this utility model are also within the scope of protection of this utility model.

Claims

1. A measuring tool for adjusting the length of a helicopter main rotor hub damper, characterized in that, The system includes a base (1), a column (2), a sliding support (3), a first vernier caliper (4), and a connecting beam (5). The base (1) has a column (2) vertically installed at both ends. The upper end of the column (2) has a sliding support (3) vertically slidably installed. Both the column (2) and the sliding support (3) have vertically installed scale lines. The column (2) and the sliding support (3) form a support unit. The height of the column (2) relative to the base (1) can be determined by reading the scale lines. The first vernier caliper (4) and the connecting beam (5) are horizontally installed between the two support units. The height of the sliding support (3) and the first vernier caliper (4) can be changed by changing the fixed position of the sliding support (3) on the column (2).

2. The helicopter main rotor hub damper length adjustment measuring tool according to claim 1, characterized in that, The sliding support (3) is provided with fastening bolts (7) for fixing the sliding support (3) to the column (2), and the sliding support (3) is a T-shaped part.

3. The helicopter main rotor hub damper length adjustment measuring tool according to claim 1, characterized in that, The sliding support (3) and the first vernier caliper (4) are respectively provided with positioning holes. The inner side of the positioning hole (8) is used to insert a positioning pin to fix the sliding support (3) and the first vernier caliper (4) together.

4. The helicopter main rotor hub damper length adjustment measuring tool according to claim 1, characterized in that, The sliding support (3) is provided with a slider (9) on one side for pushing the sliding support (3) to move up and down.

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