70 clutch plate 70 has a frictional engagement surface faced toward clutch plate 72 clutch plate 70 rotates shaft segment 50 and thereby also rotates compressor 40 fig1 clutch plate 72 is attached to a connection rod 68 extending through anchor member 66 and fixed to axially translatable housing 74 translation of housing 74 moves clutch plate 72 into one of three possible positions a first position where it is frictionally engaged to anchor member 66 a second position where it engages neither anchor member 66 nor clutch plate 70 and a third position where it engages only clutch plate 70 a compression spring 82 is coiled around shaft 68 and biases housing 74 away from anchor member 66 and thereby biases clutch plate 72 into engagement with anchor member 66 housing 74 is a generally cylindrically shaped member concentric with axis 42 housing 74 defines a stepped bore having a larger diameter section 76 and defines a smaller diameter section 77 for closely and slidingly receiving one end of shaft segment 48 larger diameter section 76 has a peripheral wall which defines a helical groove 78 winding about the end of axially fixed shaft segment 48 shaft segment 48 includes a protrusion 80 extending radially into groove 78 for camming sliding engagement along the groove so that rotation of shaft segment 48 will translate housing 74 rotation of shaft segment 48 in the direction of arrow 84 will translate housing 74 to the left in fig3 in operation engine 12 turns shaft 16 in the direction of by arrow 86 in fig1 and ultimately creates a torque on shaft segment 48 in.