The ornamental design for an eccentricshaft for a grinding machine, as shown and described.
FIG. 1 is a perspective view of an eccentric shaft for a grinding machine showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a perspective view showing the eccentric shaft in environmental structure.
The broken lines depict portions of the eccentric shaft that form no part of the claimed design.
The dot-dashed lines in FIG. 7 of the eccentric shaft for a grinding machine is for the purpose of illustrating environmental structure for the claimed design and form no part of the claimed design.