because at this time the spring 20 loosely surrounds the magnetic ring 70 when the clutch 10 is to be actuated the leads 76 of the coil 46 are connected to a source of dc potential producing a magnetic flux which causes the spring 20 to wrap tightly around the magnetic ring 70 to couple the output member 54 to the driving member means 14 to rotate therewith the spring 20 is of that variety which is commonly referred to as the wrap down type in that it is wound in a direction such that a drag on the free end of the spring 20 causes it to wrap tightly around the magnetic ring 70 in the embodiment shown the free end of the spring 20 drags on the inside diameter of the washer 50 to produce the frictional drag thereon when the coil 46 is deenergized the spring 20 relaxes to uncouple the clutch 10 the construction described enables the clutch 10 to have an improved magnetic flux pattern and enables the clutch to be produced at low cost compared to prior art clutches when the coil 46 is energized a flux pattern as shown by the closed line 78 in fig1 is generated the flux pattern 78 passes through the housing 40 the clutch spring 20 the floating magnetic ring 70 and the washer.