Rough- and finish-grinding of a crankshaft in one set-up

• US 6,878,043 B1
• Filed: 04/20/2000
• Issued: 04/12/2005
• Est. Priority Date: 04/30/1999
• Status: Expired due to Term

• Current Assignee: Erwin Junker Maschinenfabrik GmbH
• Original Assignee: Erwin Junker Maschinenfabrik GmbH
• Inventors: Junker, Erwin
• Primary Examiner(s): Morgan, Eileen P.
• Application Number:
  US09/980,764
• Time in Patent Office: 1,818 Days
• Field of Search: 451/49, 451 57- 58, 451/246, 451249-251
• US Class Current: 451/49
• CPC Class Codes: B24B 5/42 for grinding crankshafts or crankpins

Abstract

Method of grinding a concentrically clamped crankshaft, a crankshaft grinding machine for carrying out the method, and a crankshaft of high-alloy steel or cast material. The method provides for pin journals and main journals of the crankshaft to be ground in one set-up such that first, at least the main journals are rough-ground and then the pin journals are finish-ground and after that the main journals are finish-ground. The crankshaft grinding machine forms a machining center by means of which corresponding rough-grinding and finish-grinding is possible in a single set-up.

Claims

1. A method of grinding a crankshaft having pin journals and main journals in a single set-up of the crankshaft on a grinding machine, comprising the steps of:

clamping the crankshaft such that it rotates concentrically about the main journals;

first rough-grinding at least the main journals, then

finish-grinding the pin journals, thereafter

finish-grinding the main journals, and

grinding only one of the main journals as a steadyrest seat during the rough-grinding of the main journals.

2. The method as claimed in claim 1, further comprising rough-grinding the pin journals.

3. The method as claimed in claim 2, wherein the rough-grinding of the pin journals is performed after the rough-grinding of the main journals.

4. The method as claimed in one of claims 1 to 3, wherein at least some of the rough-grinding and finish-grinding is effected with a single grinding wheel.

5. The method as claimed in one of claims 1 to 3, wherein all the rough-grinding and finish-grinding is effected with one grinding wheel.

6. The method as claimed in one of claims 1 to 3, wherein all the rough-grinding and finish-grinding of at least the main journals and the pin journals is effected with one grinding wheel.

7. The method as claimed in claim 4, wherein the grinding wheel is a corundum wheel.

8. The method as claimed in claim 4, wherein the grinding wheel is a CBN wheel.

9. The method as claimed in claim 7, further comprising the step of operating the corundum wheel at a cutting speed of about 35 m/sec to about 100 m/sec.

10. The method as claimed in claim 4, wherein the grinding wheel is a ceramic CBN wheel, further comprising the step of operating the ceramic CBN wheel at a cutting speed of about 40 m/sec to about 140 m/sec.

11. The method as claimed in claim 7, further comprising the step of operating the corundum wheel at a cutting speed of about 45 m/sec to about 100 m/sec.

12. The method as claimed in claim 17, further comprising the step of operating the corundum wheel as a cutting speed of about 45 m/sec to about 70 m/sec.

13. The method as claimed in claim 4, in wherein the grinding wheel is a ceramic CBN wheel, further comprising the step of operating the ceramic CBN wheel at a cutting speed of about 80 m/sec to about 120 m/sec.

14. The method as claimed in claim 4, wherein the grinding wheel is an electroplated CBN wheel, further comprising the step of operating the electroplated CBN wheel at a cutting speed of about 80 m/sec to about 200 m/sec.

15. The method as claimed in claim 4, wherein the grinding wheel is an electroplated CBN wheel, further comprising the step of operating the electroplated CBN wheel at a cutting speed of about 100 m/sec to about 140 m/sec.

16. The method as claimed in claim 1, wherein the rough-grinding and finish-grinding are performed with separate grinding wheels.

17. The method as claimed in claim 1, wherein all the rough-grinding is effected with one grinding wheel and all the finish-grinding is effected with a separate grinding wheel.

18. The method as claimed in claim 1, wherein all the rough-grinding of at least the main journals and the pin journals is effected with one grinding wheel and all the finish-grinding of at least the main journals and the pin journals is effected with a separate grinding wheel.

19. A method of grinding a crankshaft having pin journals and main journals in a single set-up of the crankshaft on a grinding machine, comprising the steps of:

clamping the crankshaft by means of a rotatable work spindle having a chuck such that it rotates concentrically about the main journals; and

rough-grinding at least the main journals and finish-grinding the main journals and the pin journals in a sequence such that stresses in the material of the crankshaft released during the grinding are compensated for, the sequence being

first rough-grinding the main journals;

then

finish-grinding the pin journals;

thereafter

finish-grinding the main journals; and

grinding only one of the main journals as a steadyrest seat during the rough-grinding of the main journals.

20. The method as claimed in claim 19, further comprising the step of rough-grinding the pin journals after rough-grinding the pin journals and before finish-grinding the pin journals.