Gear phasing for noise control

Patent metadata

Field	Value
Publication number	US-10423756-B2
Application number	US-201615337649-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Oct 28, 2016
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

A method for designing a gear train having first and second enmeshed gears includes performing a first analysis with the first and second gears in a first configuration. The first analysis includes determining a first transmission error (TE) characteristic of the first configuration, and providing a first geometric representation of the first TE characteristic. The method also includes performing a second analysis with the first and second gears in a second configuration. The second analysis includes determining a second TE characteristic of the second configuration and providing a second geometric representation of the second TE characteristic. Moreover, the method includes providing a comparison of the first and second TE characteristics by providing a comparison of the first and second geometric representations.

First claim

What is claimed is:

1. A method for designing a gear train, the method comprising:
generating, with a modeling module, a model of a gear train in the form of an idler gear set having a first gear enmeshed with a second gear and a third gear;
inputting, with an input device, a first variable to define a first configuration of the first and second gears in the gear train;
performing, with a processor, a first analysis of the first configuration, the first analysis including determining a first transmission error (TE) characteristic of the first configuration of the first and second gears;
inputting, with the input device, a second variable to define a second configuration of the first and second gears in the gear train;
performing, with the processor, a second analysis of the second configuration, the second analysis including determining a second TE characteristic of the second configuration of the first and second gears; and
providing, with the processor, a comparison of the first TE characteristic and the second TE characteristic;
wherein the performing the first analysis includes providing a first geometric representation of the first TE characteristic including determining a change in a first vector sum of a TE force from the second gear and a TE force from the third gear during rotation of the idler gear set in the first configuration;
wherein performing the second analysis includes providing a second geometric representation of the second TE characteristic including determining a change in a second vector sum of the TE force from the second gear and the TE force from the third gear during rotation of the idler gear set in the second configuration; and
wherein providing a comparison of the first TE characteristic and the second TE characteristic includes providing a comparison of the first and second geometric representations.

2. The method of claim 1 , further comprising determining a design variable for the first gear based, at least partly, on the comparison of the first and second geometric representations.

3. The method of claim 2 , wherein determining the design variable includes at least one of:
determining a number of teeth of the first gear;
determining a tooth thickness of the first gear; and
determining a pressure angle of the first gear.

4. The method of claim 2 , wherein determining the design variable includes determining the design variable according to a comparative size of the first and second geometric representations.

5. The method of claim 2 , wherein determining the design variable includes determining the design variable according to a comparative orientation of the first and second geometric representations.

6. The method of claim 1 , wherein the first geometric representation is a first ellipse having a first axis, X, and a second axis, Y;
wherein the second geometric representation is a second ellipse having a first axis, A, and a second axis, B;
further comprising comparing the first and second ellipses by:
calculating a first root sum of squares for the first ellipse according to:
RSSo =√{square root over (( X ) 2 +( Y ) 2 )};

calculating a second root sum of squares for the second ellipse according to:
RSS =√{square root over (( A ) 2 +( B ) 2 )}; and

calculating a comparison, dB, of RSS and RSS 0 according to:
dB=20 log( RSS/RSS 0 ).

7. The method of claim 1 , wherein the first geometric representation is a first ellipse and wherein the second geometric representation is a second ellipse;
further comprising plotting the first ellipse and a second ellipse on a coordinate system.

8. The method of claim 7 , further comprising at least one of:
displaying the plot of the first and second ellipses on a display; and
generating a hard copy of the plot of the first and second ellipses.

9. A computerized tool for designing a gear train in the form of an idler gear set having a first gear enmeshed with a second gear and a third gear, the computerized tool comprising:
an input device configured to receive a first user input related to a first configuration of the gear train and to receive a second user input related to a second configuration of the gear train;
a modeling module configured to generate a model of the first configuration of the gear train and to generate a model of the second configuration of the gear train; and
a processor configured to perform a first analysis of the first configuration by determining a first transmission error (TE) characteristic of the first configuration of the gear train and providing a first geometric representation of the first TE characteristic, wherein the processor is configured to determine a change in a first vector sum of a TE force from the second gear and a TE force from the third gear during rotation of the idler gear set in the first configuration;
wherein the processor is configured to perform a second analysis of the second configuration by determining a second TE characteristic of the second configuration of the gear train and providing a second geometric representation of the second TE characteristic, wherein the processor is configured to determine a change in a second vector sum of the TE force from the second gear and the TE force from the third gear during rotation of the idler gear set in the second configuration; and
wherein the processor is configured to compare the first TE characteristic and the second TE characteristic by providing a comparison of the first and second geometric representations.

10. The computerized tool of claim 9 , wherein the processor is configured to identify a design variable for the first gear based, at least partly, on the comparison of the first and second geometric representations.

11. The computerized tool of claim 10 , wherein the processor is configured to identify at least one of:
a number of teeth of the first gear;
a tooth thickness of the first gear; and
a pressure angle of the first gear.

12. The computerized tool of claim 10 , wherein the processor is configured to compare a relative size of the first and second geometric representations.

13. The computerized tool of claim 10 , wherein the processor is configured to compare a relative orientation of the first and second geometric representations.

14. The computerized tool of claim 9 , wherein the first geometric representation is a first ellipse having a first axis, X, and a second axis, Y;
wherein the second geometric representation is a second ellipse having a first axis, A, and a second axis, B;
wherein the processor is configured to compare the first and second ellipses by:
calculating a first root sum of squares for the first ellipse according to:
RSSo =√{square root over (( X ) 2 +( Y ) 2 )};

calculating a second root sum of squares for the second ellipse according to:
RSS =√{square root over (( A ) 2 +( B ) 2 )}; and

calculating a comparison, dB, of RSS and RSS0 according to:
dB=20 log( RSS/RSS 0 ).

15. The computerized tool of claim 9 , wherein the first geometric representation is a first ellipse and wherein the second geometric representation is a second ellipse;
further comprising at least one output device that is configured to output the first ellipse and a second ellipse on a coordinate system.

16. The computerized tool of claim 15 , wherein the output device is at least one of:
a display configured to display the plot of the first and second ellipses; and
a printer configured to generate a hard copy of the plot of the first and second ellipses.

Assignees

• Deere & Co

Inventors

• White Robert J

Classifications

• F16H57/0006 Primary

  Vibration-damping or noise reducing means specially adapted for gearings (devices for varying tension of belts, ropes or chains with damping means F16H7/0829; toothed members with construction providing vibration damping F16H55/14; reducing vibrations or noise of the gearbox casing F16H57/028; suppression of vibrations or noise of gear selectors F16H59/0208; control of hydrostatic fluid gearing preventing or reducing vibrations or noise F16H61/4183) · CPC title

• G06F30/17 Primary

  Mechanical parametric or variational design · CPC title

• G06F2119/10

  Noise analysis or noise optimisation · CPC title

• G06F30/15

  Vehicle, aircraft or watercraft design · CPC title

• F16H2057/0087

  Computer aided design [CAD] specially adapted for gearing features; Analysis of gear systems · CPC title