The ornamental design for a sphygmomanometer, as shown and described.
FIG. 1 is a front perspective view of a sphygmomanometer showing our new design;
FIG. 2 is a rear perspective 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;
FIG. 7 is a right side elevational view thereof;
FIG. 8 is a left side elevational view thereof;
FIG. 9 is a front perspective view thereof with an armband and an arm plate shown in an opened position;
FIG. 10 is a rear perspective view thereof with the armband and the arm plate shown in an opened position;
FIG. 11 is a front elevational view thereof with the armband and the arm plate shown in an opened position;
FIG. 12 is a rear elevational view thereof with the armband and the arm plate shown in an opened position;
FIG. 13 is a top plan view thereof with the armband and the arm plate shown in an opened position;
FIG. 14 is a bottom plan view thereof with the armband and the arm plate shown in an opened position;
FIG. 15 is a right side elevational view thereof with the armband and the arm plate shown in an opened position; and,
FIG. 16 is a left side elevational view thereof with the armband and the arm plate shown in an opened position.
The broken lines shown in the drawings are for illustrative purposes only and form no part of the clamed design. The white areas within the broken lines form no part of the claimed design.