Gear wheel

Patent metadata

Field	Value
Publication number	US-12049948-B2
Application number	US-202017630746-A
Country	US
Kind code	B2
Filing date	Jul 30, 2020
Priority date	Jul 31, 2019
Publication date	Jul 30, 2024
Grant date	Jul 30, 2024

Abstract

The invention relates to a gear wheel for a transmission, comprising: including: a rim on which a toothing with a plurality of teeth is provided; a support point; and a web via which the rim is connected to the support point; wherein, on a side of the rim opposite the toothing and next to the web, a periodic variation of the geometry is formed that is aligned with the teeth of the toothing.

First claim

The invention claimed is:

1. A toothed gear for a gear box, comprising:
a rim on which a toothing with a plurality of teeth is positioned,
a support point,
a web via which the rim is connected to the support point,
wherein, at a side of the rim that is situated opposite the toothing and adjacent to the web, a periodic geometry variation is formed which is aligned with the teeth of the toothing; and
wherein the rim has an increasing radial rim thickness with an increasing axial distance from the web;
wherein, to form the geometry variation, a region projecting inward from the rim is formed under a respective tooth space between two adjacent ones of the teeth,
wherein two adjacent inwardly projecting regions have a same angular spacing to one another as two adjacent ones of the tooth spaces positioned radially outwardly.

2. The toothed gear as claimed in claim 1 , wherein the toothed gear has an axis of rotation, and a radius relative to the axis of rotation and to an inner surface of the rim varies in a circumferential direction about the axis of rotation.

3. The toothed gear as claimed in claim 1 , wherein the rim has different rim geometries on opposite sides of the web.

4. The toothed gear as claimed in claim 1 , wherein, to form the geometry variation, a number of periodically arranged and inwardly projecting regions are formed, wherein the number is equal to a number of teeth of the toothing.

5. The toothed gear as claimed in claim 1 , wherein the toothed gear is formed as a single piece.

6. A gear box for driving a fan of a gas turbine engine at a lower rotational speed than a core shaft of the gas turbine engine, wherein the gear box comprises:
a toothed gear which comprises a rim, on which a toothing with a plurality of teeth is positioned,
a support point, and
a web via which the rim is connected to the support point,
wherein a geometry variation and/or material variation is provided at a side of the rim that is situated opposite the toothing and adjacent to the web, and
wherein the rim has an increasing radial rim thickness with an increasing axial distance from the web;
wherein, to form the geometry variation, a region projecting inward from the rim is formed under a respective tooth space between two adjacent ones of the teeth,
wherein two adjacent inwardly projecting regions have a same angular spacing to one another as two adjacent ones of the tooth spaces positioned radially outwardly.

7. A gas turbine engine for an aircraft, comprising:
a core engine comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor;
a fan which is positioned upstream of the core engine, wherein the fan comprises a plurality of fan blades; and
the gear box as claimed in claim 6 , the gear box being driven by the core shaft, wherein the fan is driven by the gear box at a lower rotational speed than the core shaft.

8. The gas turbine engine as claimed in claim 7 , wherein:
the turbine is a first turbine, the compressor is a first compressor, and the core shaft is a first core shaft;
the core engine further comprises a second turbine, a second compressor, and a second core shaft which connects the second turbine to the second compressor; and
the second turbine, second compressor, and second core shaft are arranged to rotate at a higher rotational speed than the first core shaft.

9. A toothed gear for a gear box, comprising:
a rim on which a toothing with a plurality of teeth is positioned,
a support point,
a web via which the rim is connected to the support point,
wherein, at a side of the rim that is situated opposite the toothing and adjacent to the web, a periodic geometry variation is formed which is aligned with the teeth of the toothing; and
wherein the rim is arranged unilaterally toward a first side of the toothed gear and does not protrude from an opposite second side of the toothed gear;
wherein, to form the geometry variation, a region projecting inward from the rim is formed under a respective tooth space between two adjacent ones of the teeth,
wherein two adjacent inwardly projecting regions have a same angular spacing to one another as two adjacent ones of the tooth spaces positioned radially outwardly.

Assignees

• Rolls Royce Deutschland Ltd & Co Kg

Inventors

• Chao Chen-Xiang
• Krüger David
• Nique Michael

Classifications

• F01D15/12

  Combinations with mechanical gearing (driven by multiple engines F01D13/00) · CPC title

• F02C7/36

  Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F16H55/06

  Use of materials; Use of treatments of toothed members or worms to affect their intrinsic material properties · CPC title

• F16H2055/185

  using compound gears with coincident teeth of different material, e.g. laminated construction of metal and elastomeric gear layers, where elastic layer is slightly oversized · CPC title