We claim the ornamental design for an air circulator, as shown and described.
FIG. 1 is a front side elevation view of an air circulator embodying our design;
FIG. 2 is a rear side elevation view of the air circulator shown in FIG. 1;
FIG. 3 is a right side elevation view of the air circulator shown in FIG. 1;
FIG. 4 is a left side elevation view of the air circulator shown in FIG. 1;
FIG. 5 is top plan view of the air circulator shown in FIG. 1;
FIG. 6 is a bottom plan view of the air circulator shown in FIG. 1;
FIG. 7 is a cross sectional view taken along line 7—7 in FIG. 1, and omitting the interior mechanism; and,
FIG. 8 is a perspective view of the air circulator.
The broken line showing of a front grill, a rear grill, a hub, fan blades and two control buttons is included for the purpose of illustrating environmental structure and forms no part of the claimed design.