Machine for machining gear teeth and gear teeth machining method

Patent metadata

Field	Value
Publication number	US-9956631-B2
Application number	US-201715433726-A
Country	US
Kind code	B2
Filing date	Feb 15, 2017
Priority date	Jan 17, 2014
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A machine for machining a workpiece having a first central longitudinal axis passing through a workpiece plane that is disposed orthogonally relative to the first central longitudinal axis is provided. The machine includes a chuck or fixture on which the workpiece is disposable, a grinding spindle having a body, a wheel supporting an abrasive and an insulator electrically isolating the wheel from the body, the wheel being operable to remove material from the workpiece, the grinding spindle having a second central longitudinal axis about which the grinding spindle rotates, the second central longitudinal axis of the grinding spindle passing through the workpiece in the workpiece plane so as to create a continuous gear tooth on the workpiece and an electrochemical grinding (ECG) element configured to execute ECG processing on the grinding spindle and the workpiece to soften the workpiece as the gear tooth is being created by the grinding spindle.

First claim

What is claimed is:

1. A machine for machining a workpiece having a first central longitudinal axis passing through a workpiece plane, the workpiece plane being disposed orthogonal to the first central longitudinal axis, the machine comprising:
a grinding spindle having a body, a wheel supporting an abrasive and an insulator electrically isolating the wheel from the body, the wheel being operable to remove material from the workpiece, the grinding spindle having a second central longitudinal axis about which the grinding spindle rotates, the second central longitudinal axis of the grinding spindle passing through the workpiece in the workpiece plane so as to create a continuous gear tooth on the workpiece; and
an electrochemical grinding (ECG) element electrically connected to the wheel and the workpiece, the ECG element being configured to execute ECG processing on the grinding spindle and the workpiece to soften the workpiece as the gear tooth is being created by the grinding spindle.

2. The machine according to claim 1 , wherein the abrasive comprises a super abrasive.

3. The machine according to claim 1 , wherein the abrasive comprises a super abrasive such as cubic boron nitride (CBN).

4. The machine according to claim 1 , wherein the tip is one of conical and possessed of an involute profile.

5. The machine according to claim 1 , wherein material is removed from the workpiece by the grinding spindle in one or more of an apex gap-less double-helical shape, an apex gap-less herringbone shape and a c-shape.

6. The machine according to claim 1 , wherein the ECG element is configured to:
positively charge the workpiece,
negatively charge the grinding spindle, and
dispense electrolytic fluid toward the workpiece with the grinding spindle removing material from the workpiece.

7. The machine according to claim 1 , wherein the ECG processing on the grinding spindle and the workpiece facilitates material removal from the workpiece by the grinding spindle to a desired depth in a single pass.

8. The machine according to claim 1 , wherein the second central longitudinal axis passes through the workpiece in the workpiece plane offset from the first central longitudinal axis.

9. The machine according to claim 1 , wherein the second central longitudinal axis passes through the workpiece in the workpiece plane intersecting the first central longitudinal axis.

10. A gear comprising at least one of apex gap-less double-helical shaped teeth, apex gap-less herringbone shaped teeth and c-shaped teeth, the gear being machined by a process comprising:
disposing a workpiece having a first central longitudinal axis passing through a workpiece plane of the workpiece disposed orthogonally relative to the first central longitudinal axis on a chuck;
disposing a grinding spindle having a second central longitudinal axis such that the second central longitudinal axes passes through the workpiece in the workpiece plane;
executing ECG processing on the grinding spindle and the workpiece;
using the grinding spindle to remove material from the workpiece to form the at least one of the apex gap-less double-helical shaped teeth, apex gap-less herringbone shaped teeth and c-shaped teeth.

11. The gear according to claim 10 , wherein the apex gap-less double-helical shaped teeth, apex gap-less herringbone shaped teeth and c-shaped teeth comprise ground surfaces of less than 1 micro inch Ra and burr free edges.

12. The gear according to claim 10 , wherein the workpiece comprises high-hardness conductive materials.

13. The gear according to claim 10 , wherein the using of the grinding spindle comprises making a single pass of the grinding spindle to remove material from the workpiece to a desired depth.

14. The gear according to claim 10 , wherein disposing the grinding spindle includes positioning the grinding spindle such that the second central longitudinal axes passes through the workpiece plane of the workpiece offset relative to the first central longitudinal axis.

15. The gear according to claim 10 , wherein disposing the grinding spindle includes positioning the grinding spindle such that the second central longitudinal axes passes through the workpiece plane of the workpiece intersecting the first central longitudinal axis.

16. A method of machining a gear, comprising:
disposing a workpiece having a first central longitudinal axis passing through a workpiece plane disposed orthogonally relative to the first central longitudinal axis on a chuck;
disposing a grinding spindle having a second central longitudinal axis about which the grinding spindle rotates such that the second central longitudinal axis passes through the workpiece in the workpiece plane;
executing ECG processing on the grinding spindle and the workpiece to soften an area of the workpiece;
using the grinding spindle to remove material from the area of the workpiece to create a continuous gear tooth having one of apex gap-less double-helical shaped gear teeth, apex gap-less herringbone shaped gear teeth and c-shaped gear teeth.

17. The method according to claim 16 , wherein the using of the grinding spindle comprises making a single pass of the grinding spindle to remove material from the workpiece to a desired depth.

18. The method of claim 16 , wherein disposing the grinding spindle includes positioning the grinding spindle such that the second central longitudinal axes passes through the workpiece plane of the workpiece offset relative to the first central longitudinal axis.

19. The gear according to claim 16 , wherein disposing the grinding spindle includes positioning the grinding spindle such that the second central longitudinal axes passes through the workpiece plane of the workpiece intersecting the first central longitudinal axis.

Assignees

• Sikorsky Aircraft Corp

Inventors

• Bittner Edward H

Classifications

• B23F7/00

  Making herringbone gear teeth · CPC title

• B23F5/02

  by grinding · CPC title

• B23H5/08

  Electrolytic grinding · CPC title

• B23H5/06

  Electrochemical machining combined with mechanical working, e.g. grinding or honing · CPC title

• B23P15/14

  gear parts, e.g. gear wheels · CPC title