The ornamental design for a frame for combinedbackpack and chair, as shown and described.
FIG. 1 is a perspective front, right view of the frame for combined backpack and chair;
FIG. 2 is an orthogonal right side view of the frame for combined backpack and chair;
FIG. 3 is an orthogonal back view of the frame for combined backpack and chair;
FIG. 4 is an orthogonal front view of the frame for combined backpack and chair;
FIG. 5 is an orthogonal top view of the frame for combined backpack and chair; and,
FIG. 6 is an orthogonal bottom view of the frame for combined backpack and chair.
An orthogonal left side view is not shown but is claimed as a mirror image of FIG. 2. The broken lines in FIGS. 2 and 3 are for illustrating the backpack environment of the frame for combined backpack and chair and form no part of the claimed design. The contour lines shown in the drawings represent the three dimensional contour of the design and are not intended to indicate surface decoration.