FIG. 1 is a left side elevational view of a first embodiment of a part of a coffee machine in accordance with my design;
FIG. 2 is a right side elevational view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof; and
FIG. 7 is a perspective view thereof;
FIG. 8 is a right side elevational view of a second embodiment of a part of a coffee machine in accordance with my design;
FIG. 9 is a left side elevational view thereof;
FIG. 10 is a front elevational view thereof;
FIG. 11 is a rear elevational view thereof;
FIG. 12 is a top plan view thereof;
FIG. 13 is a bottom plan view thereof; and
FIG. 14 is a perspective view thereof;
FIG. 15 is a right side elevational view of a third embodiment of a part of a coffee machine in accordance with my design;
FIG. 16 is a left side elevational view thereof;
FIG. 17 is a front elevational view thereof;
FIG. 18 is a rear elevational view thereof;
FIG. 19 is a top plan view thereof;
FIG. 20 is a bottom plan view thereof; and
FIG. 21 is a perspective view thereof;
FIG. 22 is a right side elevational view of a fourth embodiment of a part of a coffee machine in accordance with my design;
FIG. 23 is a left side elevational view thereof;
FIG. 24 is a front elevational view thereof;
FIG. 25 is a rear elevational view thereof;
FIG. 26 is a top plan view thereof;
FIG. 27 is a bottom plan view thereof; and
FIG. 28 is a perspective view thereof;
FIG. 29 is a right side elevational view of a fifth embodiment of a part of a coffee machine in accordance with my design;
FIG. 30 is a left side elevational view thereof;
FIG. 31 is a front elevational view thereof;
FIG. 32 is a rear elevational view thereof;
FIG. 33 is a top plan view thereof;
FIG. 34 is a bottom plan view thereof; and
FIG. 35 is a perspective view thereof;
FIG. 36 is a perspective view of a sixth embodiment of a part of a coffee machine in accordance with my design;
FIG. 37 is a right side elevational view of a seventh embodiment of a part of a coffee machine in accordance with my design;
FIG. 38 is a left side elevational view thereof;
FIG. 39 is a front elevational view thereof;
FIG. 40 is a rear elevational view thereof;
FIG. 41 is a top plan view thereof;
FIG. 42 is a bottom plan view thereof; and
FIG. 43 is a perspective view thereof;
FIG. 44 is a right side elevational view of a seventh embodiment of a part of a coffee machine in accordance with my design;
FIG. 45 is a left side elevational view thereof;
FIG. 46 is a front elevational view thereof;
FIG. 47 is a rear elevational view thereof;
FIG. 48 is a top plan view thereof;
FIG. 49 is a bottom plan view thereof; and,
FIG. 50 is a perspective view thereof.
The blurred lines in the FIGS. 8-50 represent portions of the part of a coffee machine in which the design is embodied that form no part of the claimed design.