We claim the ornamental design for a vacuum cleaner, as shown and described.
FIG. 1 is a front perspective view of a first embodiment of a vacuum cleaner showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left-side view thereof;
FIG. 5 is a right-side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is a rear perspective view of thereof;
FIG. 9 is a front perspective view thereof showing the dust inhalator in an extended position;
FIG. 10 is a front perspective view of a second embodiment thereof;
FIG. 11 is a front view thereof;
FIG. 12 is a rear view thereof;
FIG. 13 is a left-side view thereof;
FIG. 14 is a right-side view thereof;
FIG. 15 is a top view thereof;
FIG. 16 is a bottom view thereof; and,
FIG. 17 is a rear perspective view thereof.
The broken lines in the figures show portions of a vacuum cleaner which are environmental structure and form no part of the claimed design. The dot-dash broken lines define boundaries of the claimed design and form no part thereof.