Method for measuring the outer contour of a floating planetary structure with self-aligning bearings

Abstract

The application provides a method for measuring the outer contour of a floating planetary structure of a self-aligning bearing, comprising: determining structure A and structure B fixedly connected with an inner ring and an outer ring of the self-aligning bearing; using a fixed tool to control the structure A and the structure B, measuring corresponding outer contour values in a maximum outer contour state, in a working condition limit state, and in a non-aligning state; and judging whether the planetary structure is assembled and whether there is interference at the assembly position according to the measured outer contour values. The maximum size of the structure in a certain direction can be accurately measured by the tool, and whether the floating planetary structure of the self-aligning bearing interferes with other structures can be more accurately judged.

Description

Technical Field

[0001] This invention belongs to the field of mechanical structure technology, specifically relating to a method for measuring the outer contour of a floating planetary structure with self-aligning bearings. Background Technology

[0002] To meet the requirements of high reduction ratios, high power, and lightweight design, helicopter gearboxes often employ compact planetary structures with large reduction ratios. Some high-power gearboxes, due to space and strength limitations, utilize two consecutive planetary structures for reduction. Due to machining and assembly errors, the torque transmission process of each planetary gear in the planetary structure cannot be guaranteed to be completely consistent. Therefore, a portion of the planetary structure often operates in a floating manner to distribute torque as evenly as possible among the planetary gears. The components connecting the two stages of planetary gears are also within the floating planetary structure. In this case, the floating planetary structure contains coaxial components with different rotational speeds, often using self-aligning bearings as the connection and support between these components. Consequently, while the entire floating planetary structure operates within the gearbox, the floating planetary structure itself undergoes deformation due to the self-aligning characteristics of the internally mounted self-aligning bearings. Therefore, it is necessary to measure the maximum outer contour of the floating planetary structure's deformation to determine whether it will contact or interfere with other structures within the gearbox, affecting its operation.

[0003] Currently, the commonly used outer contour dimensions of floating planetary structures with self-aligning bearings are calculated solely by superimposing the maximum dimensions of all components within the structure. This method only calculates the theoretical contour size and cannot reflect the influence of factors such as component tolerances and bearing clearance tolerances on the contour. Furthermore, direct measurement of floating planetary structures with self-aligning bearings makes it difficult to control the bearing self-aligning effect, resulting in inaccurate measurements. Direct trial assembly checks for interference are also hampered by external structures such as the gear ring and planetary carrier, preventing detection. While the floating planetary structure may appear interference-free in calculations, interference is possible during actual use, causing interference wear and damage to various components, including the floating planetary structure, thus affecting the normal operation of the reducer. Summary of the Invention

[0004] This invention provides a method for measuring the outer contour of a floating planetary structure with self-aligning bearings. By using tooling to accurately measure the maximum dimension of the structure in a certain direction, it is possible to more accurately determine whether the floating planetary structure with self-aligning bearings interferes with other structures.

[0005] This invention provides a method for measuring the outer contour of a floating planetary structure with self-aligning bearings, comprising: Determine structure A and structure B for the fixed connection between the inner and outer rings of the self-aligning bearing; Using fixed tooling to control structure A and structure B, measure the corresponding outer contour values ​​under the maximum outer contour state, the operating limit state, and the state without self-alignment. The measured outer contour values ​​are used to determine the planetary structure assembly and whether there is interference with the assembly location.

[0006] Optionally, the position of the fixtures used to control structures A and B may be avoided in the measurement area of ​​the outer contour.

[0007] Optionally, when the surface of a floating planetary gear structure with self-aligning bearings is difficult to measure directly, a fixed tooling can be used to convert the surface into the plane to be measured.

[0008] Optionally, the fastening points on the fixture that contact structure A and structure B may be made of a hard plastic with a lower hardness than the clamped parts.

[0009] Optionally, measure the corresponding outer contour values, including: The corresponding outer contour value is measured using a ruler or coordinate measuring machine.

[0010] Optionally, measure the corresponding outer contour values, including: When the outer contour is a straight line, the length dimension is measured using calipers, micrometers, or a coordinate measuring machine.

[0011] Optionally, measure the corresponding outer contour values, including: When the outer contour is a circular arc or an irregular plane, a coordinate measuring machine is used for multi-point sampling and projection measurement.

[0012] Optionally, the assembly of the planetary structure and whether there is interference with the assembly location can be determined based on the measured outer contour values, including: Based on the maximum outer contour, the outer contour corresponding to the extreme working condition, and the outer contour under the non-aligning working state, determine whether there are obvious errors in the assembly and whether there is assembly interference. If none of these apply, compare the measured values ​​of the maximum outer contour and the outer contour under operating conditions with the installation space dimensions of the floating planetary gear structure with self-aligning bearings to check for any interference.

[0013] This method provides a way to measure the outer contour of a floating planetary gear structure with self-aligning bearings. This method allows for the inspection of the actual outer contour of the structure using tooling before assembly, checking for any interference between the structure and its installation position. This avoids problems such as contact wear and peeling caused by interference with other structures, reducing the failure rate of the reducer. This method is particularly effective in reducing interference issues when the structure has a large number of parts.

[0014] This method can be used in existing helicopter gearboxes with planetary structures. The fixing and measuring fixtures are reusable and do not damage or otherwise adversely affect the gearbox product, exhibiting good versatility and repeatability. The fixtures described in this method can be reused in the assembly and adjustment of the same model of gearbox, and the entire adjustment process does not involve the consumption of other auxiliary materials, making it highly economical. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the fixed outer contour of a planetary structure. Figure 1 ; Figure 2 This is a schematic diagram of the fixed outer contour of a planetary structure. Figure 2 ; Figure 3 This is a schematic diagram of a planetary structure with its outer contour fixed in a non-aligned state. Figure 4 This is a schematic diagram of the method for measuring the outer contour dimensions; Explanation of reference numerals in the attached figures: 1-Base; 2-Measuring rod; 3-Adjustable measuring rod; 4-Indenter; P1 - First axial measurement surface; P2 - Second axial measurement surface. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0019] In the description of this invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing and simplifying the invention, and should not be construed as limiting the invention. Furthermore, the use of ordinal numbers (e.g., "first and second," etc.) is for distinguishing objects and is not limited to this order, and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, encompassing both direct connection and indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0021] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0023] This invention provides a method for measuring the outer contour of a floating planetary gear structure with self-aligning bearings in a helicopter gearbox. By using tooling to accurately measure the maximum dimension of the structure in a certain direction, it is possible to more accurately determine whether the floating planetary gear structure with self-aligning bearings interferes with other structures.

[0024] This invention utilizes a fixed fixture to control the self-aligning capability of a self-aligning bearing. It identifies the various structural components (links) that control the position of the inner and outer rings of the bearing. For each ring, one component is selected that is most easily controlled externally. The fixed fixture is used to maintain this component at its maximum position in the direction to be measured. The maximum value in that direction is then measured using a ruler or coordinate measuring machine. By measuring in multiple directions using this method, the outer contour value of the floating planetary gear structure with the self-aligning bearing can be obtained. This contour value is then used to determine whether there will be interference at the assembly points.

[0025] First, assemble the floating planetary gear structure with self-aligning bearings separately according to the design drawings, and locate links A and B (structures A and B) that can control the positions of the inner and outer rings of the self-aligning bearings. Then, use multiple (adjustable number) fixing fixtures to fix links A and B at multiple locations, avoiding the measurement positions in the direction to be measured. Adjust the fixing positions of links A and B by adjusting the fixing fixtures at different locations, adjusting the floating planetary gear structure with self-aligning bearings to the actual maximum value in the direction to be measured. The measured actual value is the maximum profile value in that direction.

[0026] Furthermore, components A and B are selected to be rigidly connected to the inner and outer rings of the self-aligning bearing, and other components besides the self-aligning bearing are also rigidly connected to components A and B.

[0027] Furthermore, the plane being measured can be on links A and B, in which case the tooling fixing links A and B must avoid the measurement area.

[0028] Furthermore, when the surface of a floating planetary gear structure with self-aligning bearings is difficult to measure directly, the measured plane can be transformed by tooling. That is, by adding measuring tooling to the floating planetary gear structure with self-aligning bearings, the measuring surface can be transformed from the surface of the part on the structure to the surface of the tooling, and the measuring tooling and the fixed tooling can be combined into the same tooling.

[0029] Furthermore, the fastening positions of contact links A and B on the fixed fixture are made of common plastic materials such as hard plastics with a hardness lower than that of the clamped parts.

[0030] Furthermore, when measuring the maximum profile value in a certain direction, a coordinate measuring machine can be used for projection measurement, which is suitable for situations where the surface of a floating planetary gear structure with self-aligning bearings does not have a suitable surface or it is difficult to measure the maximum value.

[0031] Furthermore, the fixed fixture can measure the outer contour dimensions of the floating planetary gear structure in the non-aligned state or in a fixed self-aligning angle state of the self-aligning bearing. The fixed fixture is used to fix link A and link B and ensure that one of the links is in a horizontal state. Then, a level or angle measuring instrument is used to assist in adjusting the other link until it reaches a horizontal state or a fixed self-aligning angle state. After the fastening fixture is tightened, the measurement can be performed in the non-aligned state or in a fixed self-aligning angle state of the self-aligning bearing.

[0032] Furthermore, the torque applied when the fixture is tightened is sufficient to ensure that the floating planetary gear structure with self-aligning bearings no longer exhibits floating deformation.

[0033] Furthermore, the fixed fixture can be a set of fixture components consisting of a group of fixture parts, wherein multiple fixture parts for fastening links A and B can be used simultaneously.

[0034] The specific implementation method is as follows: (1) Identify the parts in the floating planetary gear structure with self-aligning bearings that are rigidly connected to the inner and outer rings of the bearings. Based on the structural characteristics of these parts, identify the parts that can be fixed in position as links A and B. If multiple parts can serve as links A and B, choose the method that is more convenient to fix and easier to design the tooling to determine links A and B.

[0035] (2) Determine the measurement positions of the outer contour dimensions based on the overall shape of the floating planetary gear structure with self-aligning bearings, and avoid these measurement positions when selecting fixed tooling.

[0036] (3) Determine the position of the fixed floating planetary gear structure with self-aligning bearing, and confirm whether there are any difficult-to-measure positions. Select a fixed fixture to fix link A and link B. The fixed fixture can fit with the measurement position to change the measurement surface for easy measurement. The fixed fixture can be adjusted to meet the fixing requirements of different positions.

[0037] (4) Fixing links A and B using a fixture according to the maximum outer contour of the floating planetary gear structure with self-aligning bearings, and checking whether links A and B are movable after fixing. If they are movable, increase the fastening force of the fixture. If they are still movable after increasing the fastening force, add more fixtures to assist in fixing.

[0038] (5) Measure the outer contour value of the fixed floating planetary gear structure with self-aligning bearing. The straight length dimension can be measured with calipers, micrometers or coordinate measuring machines. The arc dimension, irregular plane or other dimensions that are difficult to measure directly can be measured by projection measurement using multi-point sampling of a coordinate measuring machine.

[0039] (6) Based on the operating conditions of the floating planetary gear structure with self-aligning bearings, use a fixing fixture to fix the bearings at a certain angle. During fixing, use an angle measuring instrument to assist in adjustment at link A or link B where the angle is affected. If the self-aligning bearings do not need to be self-aligned, a level can be used to assist in adjustment when using the fixing fixture. After fixing, measure all dimensions of the outer contour.

[0040] (7) Compare the measured values ​​of the maximum outer contour and the outer contour under operating conditions with the installation space dimensions of the floating planetary gear structure with self-aligning bearings to check for any interference. Determine whether the structure needs adjustment or modification based on the interference check results.

[0041] Example like Figure 1-4 As shown, the process of measuring the outer contour of a helicopter reducer with a self-aligning bearing and floating planetary gear structure is as follows.

[0042] (1) The helicopter gearbox contains a two-stage planetary structure connected in series. The first-stage sun gear, the first-stage planetary carrier, and the second-stage sun gear are floating structures, and there is an axial self-aligning bearing between the first-stage sun gear and the first-stage planetary carrier. The first-stage planetary carrier and the second-stage sun gear are rigidly connected. Therefore, the first-stage sun gear is identified as stage A, and both the first-stage planetary carrier and the second-stage sun gear can be identified as stages B. Figure 1 It is evident that the first-stage planetary gear carrier has no selectable clamping position, and the second-stage sun gear is selected as stage B for ease of tooling design.

[0043] (2) The floating planetary gear structure with self-aligning bearing operates in a vertical axis state, and all parts in the structure are arranged along the circumference of the axis. Therefore, the maximum outer contour is the maximum axial dimension and the maximum radial circumferential diameter when the axial self-aligning bearing is deformed to its maximum value. Therefore, the axial measurement positions are the end faces of the first-stage sun gear and the second-stage sun gear (e.g., ...). Figure 1 As shown, the first axial measuring surface P1 and the second axial measuring surface P2), the radial circumferential measuring position is the largest outer circumference surface of the planetary gear (e.g., Figure 1 (The circumferential measurement location is shown).

[0044] (3) Based on the characteristic of the through-hole inner diameter of the first-stage sun gear in stage A, a base with a cylindrical protrusion is selected to fix the fixture (e.g., Figure 1 The fixed fixture shown is used to fix link A, and at the same time, the first axial measuring surface P1 of the base fixing fixture is fully attached to the axial measuring surface of link A. While fixing link A, the first axial measuring surface P1 of the fixture is directly attached to the axial measuring surface of link A, and the axial measuring surface of link A measured during axial measurement is directly converted into the first axial measuring surface P1 of the base 1 to facilitate measurement.

[0045] (4) Install four adjustable measuring rods (such as...) evenly distributed around the circumference of the base fixing fixture. Figure 1 The measuring rod 2 shown) and the clamping fixture (such as Figure 1 The adjustable measuring rod 3 and pressure head 4 are shown. The adjustable measuring rod 3 can move axially and rotate circumferentially on the measuring rod 2 to meet the clamping requirements of different axial heights and circumferential angles. The clamping fixture clamps link B at multiple positions around the circumference when the axial deformation of the self-aligning bearing is at its maximum, i.e., when the deformation of link B is at its maximum. After clamping, check whether link B is movable. If it is movable, increase the clamping force of the fixture.

[0046] (5) Using a coordinate measuring machine, measure the axial height value Z1 of the first axial measuring surface P1 of the base fixing fixture, which is 0 mm. After measuring multiple actual positions of the second axial measuring surface P2 on the end face of the second-stage sun gear, fit the plane and project it onto the YZ plane to confirm the maximum axial height value Z2 = 201.29 mm. After measuring multiple actual radial positions of the planet gear at the circumferential measuring point using a coordinate measuring machine, fit the plane and project it onto the XY plane to confirm the maximum radial radius dimension R = 251.22 mm.

[0047] (6) Adjust the adjustable measuring rod and clamping fixture to clamp link B under the working condition limit conditions, fix links A and B again, and use an angle measuring instrument to measure whether link B is under the working condition limit conditions. Then measure Z1=0mm, Z2=200.98mm, R=251.13mm in the manner of item (5).

[0048] (7) Based on the normal operating state of the helicopter reducer with self-aligning bearing floating planetary gear structure in the non-aligning state, adjust the adjustable measuring rod and clamping fixture to make the end face of the secondary sun gear (e.g. Figure 1 After the second axial measuring surface P2 shown becomes horizontal, fix links A and B again, and use a level to measure whether the end face of the second-stage sun gear is horizontal. Then measure Z1=0mm, Z2=200.53mm, and R=251.04mm in accordance with the method in section (5).

[0049] (8) Based on the maximum outer contour, the outer contour corresponding to the extreme working condition, and the outer contour under the non-aligning working state, determine whether there are obvious errors in the assembly and whether there is assembly interference; if none are found, proceed to (9). (9) The minimum axial working space of the floating structure in the helicopter gearbox is 201.5 mm, and the minimum radial working space is 260 mm. Based on the measurement results, it is determined that the floating structure is smaller than the minimum working space size in both the axial and radial directions, so the floating structure will not interfere with other parts.

[0050] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A method for measuring the outer contour of a floating planetary structure with self-aligning bearings, characterized in that, include: Determine structure A and structure B for the fixed connection between the inner and outer rings of the self-aligning bearing; Using fixed tooling to control structure A and structure B, measure the corresponding outer contour values ​​under the maximum outer contour state, the operating limit state, and the state without self-alignment. The measured outer contour values ​​are used to determine the planetary structure assembly and whether there is interference with the assembly location.

2. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, The fixtures used to control structures A and B are positioned to avoid the measurement area of ​​the outer contour.

3. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, When the surface of a floating planetary gear structure with self-aligning bearings is difficult to measure directly, a fixed fixture is used to transform the surface into the plane to be measured.

4. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, The fastening points on the fixture that contact structure A and structure B are made of hard plastic with a lower hardness than the parts being clamped.

5. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, Measure the corresponding outer contour values, including: The corresponding outer contour value is measured using a ruler or coordinate measuring machine.

6. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, Measure the corresponding outer contour values, including: When the outer contour is a straight line, the length dimension is measured using calipers, micrometers, or a coordinate measuring machine.

7. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, Measure the corresponding outer contour values, including: When the outer contour is a circular arc or an irregular plane, a coordinate measuring machine is used for multi-point sampling and projection measurement.

8. The method for measuring the outer contour of a floating planetary structure with self-aligning bearings according to claim 1, characterized in that, Determine the planetary structure assembly and whether there is interference at the assembly location based on the measured outer contour values, including: Based on the maximum outer contour, the outer contour corresponding to the extreme working condition, and the outer contour under the non-aligning working state, determine whether there are obvious errors in the assembly and whether there is assembly interference. If none of these apply, compare the measured values ​​of the maximum outer contour and the outer contour under operating conditions with the installation space dimensions of the floating planetary gear structure with self-aligning bearings to check for any interference.

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