The ornamental design for a safetybed, as shown and described.
FIG. 1 is a perspective view of a safety bed;
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; the right side view being an identical image thereof; and,
FIG. 5 is a top plan view thereof; the bottom plan view being an identical image thereof.
The article is shown with a symbolic break in its length and width. The appearance of any portion of the article between the break lines forms no part of the claimed design.