Method for journal finishing of crankshafts, camshafts, and journals

Patent metadata

Field	Value
Publication number	US-10639763-B2
Application number	US-201715813076-A
Country	US
Kind code	B2
Filing date	Nov 14, 2017
Priority date	Nov 14, 2017
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

A method of grinding a surface of a crankshaft is provided. The method includes grinding the surface of the crankshaft by a grinding wheel, and polishing the surface of the crankshaft ground by the grinding wheel by oscillating a polishing wheel in a transverse direction perpendicular to a longitudinal direction of the crankshaft.

First claim

What is claimed is:

1. A method of grinding a surface of a workpiece, the method comprising:
grinding the surface of the workpiece by a grinding wheel; and
polishing the surface of the workpiece ground by the grinding wheel by oscillating a polishing wheel at a frequency between 2-25 Hz in a transverse direction perpendicular to a longitudinal direction of the crankshaft.

2. The method according to claim 1 , further comprising oscillating the polishing wheel at a stroke between 0.05-1.0 mm.

3. The method according to claim 1 , further comprising applying a coolant during the polishing.

4. The method according to claim 3 , wherein the coolant includes 6% water.

5. The method according to claim 1 , wherein the polishing wheel is a cubic boron nitride (CBN) wheel.

6. The method according to claim 5 , wherein the polishing wheel has a grain size between 15-76 microns.

7. The method according to claim 5 , wherein the polishing wheel has 400 grit.

8. The method according to claim 5 , wherein the polishing wheel is a vitrified CBN wheel.

9. The method according to claim 5 , wherein the polishing wheel is a resin-bonded CBN wheel.

10. The method according to claim 1 , wherein the polishing wheel removes stock material from the crankshaft at a depth of 20 microns.

11. The method according to claim 1 , further comprising performing the grinding by plunge-grinding.

12. The method according to claim 11 , wherein the plunge-grinding is performed by using a CBN wheel.

13. The method according to claim 11 , wherein the CBN wheel for the plunge-grinding has a grain size of 151 microns.

14. The method according to claim 11 , wherein the CBN wheel has 120 grit.

15. The method according to claim 1 , wherein the surface is a surface of a main bearing journal or a pin journal of a crankshaft.

16. A method of grinding and polishing a surface of a crankshaft, the method comprising:
grinding the surface of the crankshaft by a grinding wheel; and
polishing the surface of the crankshaft ground by the grinding wheel by oscillating a vitrified or resin-bonded cubic boron nitride (CBN) wheel having a grain size no greater than 46 microns at a frequency between 2-25 Hz in a transverse direction perpendicular to a longitudinal direction of the crankshaft.

17. A method of grinding and polishing main bearing journals and pin journals of a crankshaft, the method comprising:
grinding the surface of the crankshaft by a grinding wheel; and
oscillating a polishing wheel at a stroke between 0.05-1.0 mm and a frequency between 2-25 Hz in a transverse direction perpendicular to a longitudinal axis of the crankshaft to polish the surface ground by the grinding wheel.

18. The method according to claim 17 , wherein the polishing wheel has a grain size no greater than 46 microns.

Assignees

• Ford Motor Co

Inventors

• Kopmanis Michael A

Classifications

• B24D7/06

  with inserted abrasive blocks, e.g. segmental · CPC title

• B24B19/125

  electrically controlled, e.g. numerically controlled · CPC title

• B24D5/06

  with inserted abrasive blocks, e.g. segmental · CPC title

• B24D9/08

  Circular back-plates for carrying flexible material · CPC title

• B24B55/02

  Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant (cooling or lubricating during dressing operation B24B53/095; incorporated in grinding wheels B24D) · CPC title