The ornamental design for an electric chainhoist, as shown and described.
FIG. 1 is a perspective view of the electric chain hoist
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a left side elevation view thereof;
FIG. 5 is a right side elevation view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a perspective view thereof showing an example in use; and,
FIG. 8 is a perspective view thereof showing an example in use.
The broken lines shown in the figures are included for the purpose of illustrating portions of the electric chain hoist and form no part of the claimed design.