The ornamental design for a disclightingfixture with an inverted cone, as shown and described.
FIG. 1 is a perspective view of a disc lighting fixture with an inverted cone showing the new design;
FIG. 2 is a side view of the disc lighting fixture as shown in FIG. 1, the opposite side of the disc lighting fixture being a mirror image thereof;
FIG. 3 is a top view of the disc lighting fixture as shown in FIG. 1; and,
FIG. 4 is a bottom view of the disc lighting fixture as shown in FIG. 1.
Features shown in dashed lines immediately adjacent the shaded areas or adjacent the solid lines represent the bounds of the claim and all other dashed lines are for illustrative purposes only. None of the dashed lines form a part of the claimed design.