The ornamental design for sprinkler apparatus, as shown and described.
FIG. 1 is a perspective view from the front and above of the sprinkler apparatus showing my new design;
FIG. 2 is a perspective view from below and to the left side of the sprinkler apparatus, as shown in FIG. 1, and showing one design of a stencil in phantom not forming part of the claimed design;
FIG. 3 is an elevational view of the right side of the sprinkler apparatus, as shown in FIG. 1;
FIG. 4 is an elevational view of the left side of the sprinkler apparatus, as shown in FIG. 1;
FIG. 5 is an elevational view of the front of the sprinkler apparatus;
FIG. 6 is an elevational view of the rear of the sprinkler apparatus;
FIG. 7 is a plan view from above of the sprinkler apparatus; and,
FIG. 8 is a plan view from below of the sprinkler apparatus.