Star gear train multi-path gear and design method and system thereof

Abstract

The invention belongs to the technical field of engines, and provides a star gear train multi-path gear and a design method and system.The method comprises the steps that design parameters of an output center gear, an input center gear and duplicate gears and the set number of the duplicate gears are determined based on design requirements; the first bevel gear is adjusted and controlled based on the starting working face of the second bevel gear reference circle; a set number of duplicate gears are selected for matching; the output center wheel, the input center wheel and the duplicate gears are measured to obtain a structure size chain, and the nominal height of each duplicate gear is obtained based on the structure size chain; and measuring the run-out value of each duplicate gear, and correspondingly adjusting the height of each duplicate gear in combination with the nominal height of each duplicate gear to finish the design. According to the star gear train multi-path gear design method, through two-time limiting and axial position adjusting, the technical effects that the input-stage gear pair and the output-stage gear pair at the two ends of the duplicate gear are meshed at the same time and the split multi-path duplicate gear is meshed at the same time are guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of engines, and in particular relates to a planetary gear train multi-path gear and a design method and system thereof. Background Art

[0002] In aircraft engine transmission systems, a planetary gear reducer is a typical power-split fixed-axis transmission structure. It achieves power distribution through multiple planetary gears to improve load capacity and reduce structural dimensions. Planetary gears typically utilize a duplex gear structure, with one end meshing with the input center gear and the other end meshing with the output center gear. To enhance transmission smoothness and load capacity, helical gears are typically used at both ends of the planetary gear.

[0003] However, due to manufacturing errors (such as pitch deviation and tooth direction error) and assembly errors (such as shaft alignment deviation and bearing clearance), the input and output gear pairs at both ends of the star wheel cannot achieve synchronous meshing, which directly affects the load-bearing capacity and reliability of the gear system; if the meshing is not synchronized, it will increase friction loss and reduce transmission efficiency. Excessive angular deviation between multiple star wheels will cause some star wheels to overload, reducing the fatigue life and reliability of the system.

[0004] In view of this, overcoming the defects of the above-mentioned prior art is an urgent problem to be solved in this technical field. Summary of the Invention

[0005] In view of the above problems, the present invention proposes a method for designing a multi-path gear of a planetary gear train, comprising the following steps:

[0006] Determining design parameters of the output center gear, the input center gear, and the duplex gears, as well as a set number of duplex gears based on design requirements, wherein the duplex gears include a first helical gear connected to the input center gear and a second helical gear connected to the output center gear;

[0007] Adjusting the first helical gear based on the starting working surface of the second helical gear pitch circle until the angular deviation between the first helical gear and the second helical gear is less than a first limit value;

[0008] A set number of duplex gears are selected for grouping, and the difference in angular deviation between any two duplex gears in the same group is less than a second limit;

[0009] Measure the output center gear, input center gear, and duplex gears to obtain the structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain;

[0010] Measure the runout value of each duplex gear, adjust the height of each duplex gear accordingly based on the nominal height of each duplex gear, and complete the design.

[0011] Furthermore, the first limit value is 0.02-0.04 mm.

[0012] Furthermore, the second limit value is 0.02 mm.

[0013] Furthermore, the height of each duplex gear is adjusted accordingly based on the nominal height of each duplex gear, including:

[0014] Determine the runout value of the first duplex gear, and then obtain the runout value difference between each duplex gear in the same group and the first duplex gear;

[0015] The sum of the difference between the nominal height of each duplex gear and the corresponding runout value is selected as the height of the corresponding duplex gear.

[0016] Furthermore, the design quantity is an integer multiple of 3.

[0017] The present invention also provides a planetary gear train multi-path gear design system, comprising:

[0018] a first design unit, configured to determine, based on design requirements, design parameters of the output center gear, the input center gear, and the duplex gears, as well as a set number of duplex gears, wherein the duplex gears include a first helical gear connected to the input center gear and a second helical gear connected to the output center gear;

[0019] a regulating unit, configured to regulate the first helical gear based on a starting working surface of a pitch circle of the second helical gear until an angular deviation between the first helical gear and the second helical gear is less than a first limit value;

[0020] A matching unit is used to select a set number of duplex gears for matching, and the difference in angular deviation between any two duplex gears in the same group is less than a second limit value;

[0021] The measuring unit is used to measure the output center gear, input center gear, and duplex gears to obtain the structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain;

[0022] The second design unit is used to measure the runout value of each duplex gear, and adjust the height of the duplex gear accordingly based on the nominal height of each duplex gear to complete the design.

[0023] Furthermore, the first limit value is 0.02-0.04 mm.

[0024] Furthermore, the second limit value is 0.02 mm.

[0025] Furthermore, the measurement unit is specifically used for:

[0026] Determine the runout value of the first duplex gear, and then obtain the runout value difference between each duplex gear in the same group and the first duplex gear;

[0027] The sum of the difference between the nominal height of each duplex gear and the corresponding runout value is selected as the height of the corresponding duplex gear.

[0028] The present invention also provides a planetary gear train multi-path gear, which is designed using the planetary gear train multi-path gear design method.

[0029] Compared with the prior art, the embodiments of the present invention have at least the following advantages:

[0030] The multi-path gear design method of the star gear system of the present invention realizes the first limitation of the star gear system by regulating the angular deviation value of the dividing arc line of the starting working surface of the two helical gears of the double gear to be no more than 0.02~0.04mm; through the multi-path diversion double gear matching design, the angular deviation difference of each double gear in the same group is limited to no more than 0.02mm, realizing the second limitation of the star gear system and improving the simultaneous meshing design accuracy; on the basis of the first two limitations, the axial position of each double gear is adjusted by the runout value and the nominal height to realize the compensation of the angular deviation of the two gears in a single double gear and the angular deviation between the matched double gears, thereby realizing the simultaneous meshing of the input stage gear pair and the output stage gear pair at both ends of the double gear and the simultaneous meshing of the diverted multi-path double gears. This method solves the problem of simultaneous meshing of multi-path gears in the multi-path diversion star gear system reducer of an aircraft engine, and has the advantages of strong process operability and high functional reliability.

[0031] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A schematic flow chart showing a method for designing a multi-path gear of a planetary gear train according to an embodiment of the present invention is shown;

[0034] Figure 2 It shows a block diagram of a multi-path gear design system for a planetary gear train according to an embodiment of the present invention;

[0035] Figure 3 The schematic diagram of the structure of the multi-path gear of the star gear train is shown.

[0036] In the figure, 1-first helical gear, 2-second helical gear. DETAILED DESCRIPTION

[0037] The following description provides many different embodiments or examples for implementing different features of the present invention. The components and arrangements described in the following specific examples are only used to simplify the present invention and are only used as examples, not to limit the present invention.

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0039] The present invention provides a method for designing a multi-path gear of a planetary gear train. Figure 1 The figure shows a flow chart of a method for designing a multi-path gear of a planetary gear train in an embodiment of the present invention. Figure 1 The method for designing a multi-path gear of a planetary gear train comprises the following steps:

[0040] S101. Determine design parameters of an output center gear, an input center gear, and duplex gears, as well as a set number of duplex gears based on design requirements. The duplex gears include a first helical gear 1 connected to the input center gear and a second helical gear 2 connected to the output center gear.

[0041] Among them, the design quantity is an integer multiple of 3, and the conventional multi-way split star gear system is generally 3 double gears, 6 double gears or 9 double gears.

[0042] S102, regulating the first helical gear 1 based on the starting working surface of the pitch circle of the second helical gear 2 until the angular deviation between the first helical gear 1 and the second helical gear 2 is less than a first limit value;

[0043] Among them, the first limit is 0.02 to 0.04 mm, which realizes the preliminary limitation of the duplex gears.

[0044] It should be noted that the starting working surface of the pitch circle refers to the specific area on the pitch circle used to determine the starting position of tooth surface contact when the gears are engaged. The starting working surface is the first tooth surface area on the pitch circle to participate in meshing, and the intersection of the pitch circle and the tooth profile is usually used as the starting point of meshing.

[0045] S103: Select a set number of duplex gears for grouping, and ensure that the difference in angular deviation between any two duplex gears in the same group is less than a second limit;

[0046] Among them, the second limit is 0.02mm, which realizes the secondary limitation of the duplex gears in the same group to improve the overall accuracy.

[0047] S104: Measure the output center gear, the input center gear, and the duplex gears to obtain a structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain;

[0048] S105. Measure the runout value of each duplex gear, and adjust the height of each duplex gear accordingly based on the nominal height of each duplex gear to complete the design.

[0049] Specifically include:

[0050] Obtain the runout value of the first duplex gear, and then obtain the runout value difference between the other duplex gears in the same group and the first duplex gear;

[0051] The sum of the difference between the nominal height of each duplex gear and the corresponding runout value is selected as the height of the corresponding duplex gear.

[0052] It should be added that the number of teeth of the first helical gear 1 and the second helical gear 2 is arbitrary. In this embodiment, three duplex gears are taken as an example to further illustrate the present application. The three duplex gears are respectively set as the first duplex gear, the second duplex gear and the third duplex gear.

[0053] The difference between the angular deviation of the first duplex gear and the angular deviation of the second duplex gear, the difference between the angular deviation of the third duplex gear and the angular deviation of the second duplex gear, and the difference between the angular deviation of the third duplex gear and the angular deviation of the first duplex gear are all less than 0.02 mm.

[0054] The first duplex gear, the second duplex gear and the third duplex gear meet the requirements of step S103 and are suitable for pairing.

[0055] Correspondingly, the nominal heights of the three duplex gears obtained based on the structural dimension chain are: t 名义1 , t 名义2 , t 名义3 ;

[0056] The simultaneous meshing compensation of each duplex gear is measured on a dedicated simultaneous meshing fixture. The dedicated simultaneous meshing fixture is a standard rack designed according to the theoretical value of the planetary gear system. The measurement principle is to mesh the duplex gear with the standard rack in the theoretical position and measure the runout value of each duplex gear shaft end.

[0057] Specifically, place the first duplex gear on a dedicated simultaneous meshing fixture and screw it in with even force until the working surfaces of both gears 1 and 2 come into contact with the working surface of the standard rack. At this point, record the dial indicator reading as t1. Without moving the dial indicator, measure the second and third duplex gears in the same manner, recording the dial indicator readings as t2 and t3, respectively.

[0058] Taking the first duplex gear as the benchmark, calculate the difference between the second duplex gear and the third duplex gear and the first duplex gear, so as to obtain the actual compensation amount. The specific method is as follows:

[0059] The measured runout value of the first duplex gear is used as a benchmark, namely:

[0060] t 1补偿 =t1-t1=0 (1);

[0061] Where t1 represents the measured runout of the first duplex gear, t 1补偿 Indicates the actual compensation amount of the first duplex gear;

[0062] The compensation amount of the second duplex gear and the third duplex gear is:

[0063] t 2补偿 =t2-t1 (2);

[0064] t 3补偿 =t3-t1 (3).

[0065] Where t2 represents the measured runout of the second duplex gear, t 2补偿 represents the actual compensation of the second duplex gear; t3 represents the measured runout of the third duplex gear, t 3补偿 Indicates the actual compensation amount of the third duplex gear.

[0066] Furthermore, the actual axial heights of the first duplex gear, the second duplex gear, and the third duplex gear after adjustment are:

[0067] t 实际1 =t 名义1 +t 1补偿 (4);

[0068] t 实际2 =t 名义2 +t 补偿2 (5);

[0069] t 实际3 =t 名义3 +t 补偿3 (6).

[0070] Where, t 实际1 Indicates the actual axial height of the first duplex gear, t实际2 Indicates the actual axial height of the second duplex gear; t 实际3 Indicates the actual axial height of the third duplex gear.

[0071] Correspondingly, in actual practical application, during the assembly process of conventional double gears, an adjustment pad connected to the axial direction of the double gear is adjusted, and an adjustment pad is set on each double gear structure of the multi-way diversion. The adjustment pad is associated with the axial position of the double gear, and the axial movement is achieved by contacting and pressing with the shoulder of the double gear (inner cavity or external shoulder), thereby realizing the regulation of the axial position of the double gear.

[0072] In this embodiment, the nominal height of each duplex gear is obtained based on the structural dimension chain, the runout value of each duplex gear is measured, and the height of each duplex gear is adjusted in combination with the nominal height of each duplex gear.

[0073] Correspondingly, the nominal height of each duplex gear is obtained based on the structural dimension chain, and the nominal height of the adjustment pad is obtained by further measuring the distance between the duplex gear and the corresponding adjustment pad; and when measuring the runout value of each duplex gear, the height of each adjustment pad is adjusted in combination with the nominal height of each adjustment pad, thereby achieving height adjustment of each duplex gear.

[0074] While the above description uses adjustment pads as an example, the present invention is not limited thereto. The height of the dual gears can also be adjusted using other axially related structures. Those skilled in the art can consider the adjustment principles of the present invention and actual application scenarios, as long as the principles of the present invention can be implemented.

[0075] It should be noted that due to the angular deviation between the first helical gear 1 and the second helical gear 2, when the input center gear is meshed with the starting working surface of the first helical gear 1, there must be a gap between the starting working surface of the second helical gear 2 and the output center gear on the pitch circle. Figure 3 By displacing the duplex gears axially, this gap is eliminated, allowing the second helical gear 2 to mesh with the starting working surface of the output center gear. However, the traditional calculation method uses the helix angle β1 and pitch circle radius r1 for the first helical gear 1, and the helix angle β2 and pitch circle radius r2 for the second helical gear 2, and then constructs the relationship between the axial displacement t and the gap Δ as follows:

[0076]

[0077] Wherein, β1 represents the helix angle of the first helical gear 1; r1 represents the pitch circle radius of the first helical gear 1; β2 represents the helix angle of the second helical gear 2; r2 represents the pitch circle radius of the second helical gear 2; t represents the axial displacement of the duplex gear; Δ represents the gap between the starting working surface of the second helical gear 2 and the output center gear when the input center gear meshes with the starting working surface of the first helical gear 1.

[0078] It can be seen that in actual engineering, if the axial displacement of the duplex gears is calculated according to the above calculation formula during the assembly of the reducer, there are at least the following problems: First, the gear manufacturing unit is required to provide the actual manufacturing parameters such as the helix angle and pitch circle diameter of all star wheels, and the assembly unit needs to perform a large amount of calculation work, which places high demands on the assembly workers and has low work efficiency; Second, the manufacturing errors in the size of the duplex gears themselves, the casing mounting holes, etc. are ignored, resulting in large deviations in the axial displacement requirements; Third, there is a lack of compensation for the angular deviation between multiple star wheels.

[0079] The present invention discloses a method for designing multi-path gears of a star gear train, which realizes the first limitation of the star gear train by regulating the angular deviation value of the dividing arc line of the starting working surface of the two helical gears of the double gear to be no more than 0.02-0.04mm; and realizes the second limitation of the star gear train by limiting the angular deviation difference of each double gear in the same group to no more than 0.02mm through the multi-path diversion double gear matching design, thereby improving the simultaneous meshing design accuracy; on the basis of the first two limitations, the axial position of each double gear is adjusted by the runout value and the nominal height to realize the compensation of the angular deviation of the two gears in a single double gear and the angular deviation between the matched double gears, thereby realizing the simultaneous meshing of the input stage gear pair and the output stage gear pair at both ends of the double gear and the simultaneous meshing of the diverted multi-path double gears. This method solves the problem of simultaneous meshing of multi-path gears in the multi-path diversion star gear train reducer of an aircraft engine, and has the advantages of strong process operability and high functional reliability.

[0080] refer to Figure 2 The present invention further discloses a multi-path gear design system for a planetary gear train, comprising: a first design unit for determining, based on design requirements, design parameters of an output center gear, an input center gear, and duplex gears, as well as a set number of duplex gears, wherein the duplex gears include a first helical gear connected to the input center gear and a second helical gear connected to the output center gear;

[0081] a regulating unit, configured to regulate the first helical gear based on a starting working surface of a pitch circle of the second helical gear until an angular deviation between the first helical gear and the second helical gear is less than a first limit value;

[0082] A matching unit is used to select a set number of duplex gears for matching, and the difference in angular deviation between any two duplex gears in the same group is less than a second limit value;

[0083] The measuring unit is used to measure the output center gear, input center gear, and duplex gears to obtain the structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain;

[0084] The second design unit is used to measure the runout value of each duplex gear, and adjust the height of the duplex gear accordingly based on the nominal height of each duplex gear to complete the design.

[0085] Correspondingly, the present invention further discloses a planetary gear train multi-path gear, including a gear designed by the above-mentioned planetary gear train multi-path gear design method.

[0086] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the specified features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0087] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical, electrical, or intercommunication connections; direct or indirect connections through an intermediary; and may encompass internal connectivity between multiple components or interactions between multiple components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0088] In the description of the present invention, it should be understood that all terms used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and cannot be understood as a limitation on the present invention.

[0089] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for designing a multi-path gear of a planetary gear train, characterized in that: The following steps are involved: Determining design parameters of the output center gear, the input center gear, and the duplex gears, as well as a set number of duplex gears based on design requirements, wherein the duplex gears include a first helical gear connected to the input center gear and a second helical gear connected to the output center gear; Adjusting the first helical gear based on the starting working surface of the second helical gear pitch circle until the angular deviation between the first helical gear and the second helical gear is less than a first limit value; A set number of duplex gears are selected for grouping, and the difference in angular deviation between any two duplex gears in the same group is less than a second limit; Measure the output center gear, input center gear, and duplex gears to obtain the structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain; Measure the runout value of each duplex gear, adjust the height of each duplex gear accordingly based on the nominal height of each duplex gear, and complete the design.

2. The method for designing a multi-path gear of a planetary gear train according to claim 1, characterized in that: The first limit value is 0.02-0.04 mm.

3. The method for designing a multi-path gear of a planetary gear train according to claim 2, characterized in that: The second limit value is 0.02 mm.

4. The method for designing a multi-path gear of a planetary gear train according to claim 3, wherein: The adjusting the height of each duplex gear in accordance with the nominal height of each duplex gear comprises: Determine the runout value of the first duplex gear, and then obtain the runout value difference between each duplex gear in the same group and the first duplex gear; The sum of the difference between the nominal height of each duplex gear and the corresponding runout value is selected as the height of the corresponding duplex gear.

5. The method for designing a multi-path gear of a planetary gear train according to claim 1, characterized in that: The design quantity is an integer multiple of 3.

6. A planetary gear train multi-path gear design system, characterized in that: include: a first design unit, configured to determine, based on design requirements, design parameters of the output center gear, the input center gear, and the duplex gears, as well as a set number of duplex gears, wherein the duplex gears include a first helical gear connected to the input center gear and a second helical gear connected to the output center gear; a regulating unit, configured to regulate the first helical gear based on a starting working surface of a pitch circle of the second helical gear until an angular deviation between the first helical gear and the second helical gear is less than a first limit value; A matching unit is used to select a set number of duplex gears for matching, and the difference in angular deviation between any two duplex gears in the same group is less than a second limit value; The measuring unit is used to measure the output center gear, input center gear, and duplex gears to obtain the structural dimension chain, and obtain the nominal height of each duplex gear based on the structural dimension chain; The second design unit is used to measure the runout value of each duplex gear, and adjust the height of the duplex gear accordingly based on the nominal height of each duplex gear to complete the design.

7. The planetary gear train multi-path gear design system according to claim 6, characterized in that: The first limit value is 0.02-0.04 mm.

8. The planetary gear train multi-path gear design system according to claim 7, characterized in that: The second limit value is 0.02 mm.

9. The planetary gear train multi-path gear design system according to claim 8, characterized in that: The measuring unit is specifically used for: Determine the runout value of the first duplex gear, and then obtain the runout value difference between each duplex gear in the same group and the first duplex gear; The sum of the difference between the nominal height of each duplex gear and the corresponding runout value is selected as the height of the corresponding duplex gear.

10. A multi-path gear of a planetary gear train, characterized in that: A gear designed using the method for designing a multi-path gear of a star gear train according to any one of claims 1 to 5.

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