The ornamental design for a convertiblechair, as shown and described.
FIG. 1 is a right side elevation view a convertible chair in a folded configuration showing the new design (the left side elevation view of the convertible chair in the folded configuration is a mirror image of the view shown in FIG. 1);
FIG. 2 is a right side front perspective view of the convertible chair in the folded configuration shown in FIG. 1 (the left side front perspective view of the convertible chair in the folded configuration is a mirror image of the view shown in FIG. 2);
FIG. 3 is a left side rear perspective view of the convertible chair in the folded configuration shown in FIG. 1 (the right side rear perspective view of the convertible chair in the folded configuration is a mirror image of the view shown in FIG. 3);
FIG. 4 is a right side front perspective view of the convertible chair shown in FIG. 1 in an unfolded configuration (the left side front perspective view of the convertible chair in the unfolded configuration is a mirror image of the view shown in FIG. 4); and,
FIG. 5 is a left side rear perspective view of the convertible chair shown in FIG. 1 in the unfolded configuration (the right side rear perspective view of the convertible chair in the unfolded configuration is a mirror image of the view shown in FIG. 5).
The broken lines shown in the drawings are for illustrative purposes only and form no part of the claimed design.
Applicant specifically disclaims any interior surface ornamentation, such as but not limited to connection means such as screws, interior slats, grooves between parts, and any other features apart from the primary outer surface of the convertible chair, all of which form no part of the claimed design.