latch as presented in fig1 components below the plane of the illustration such as spool 152 spring catchment 150 and pinion gear 116 are shown in dashed outline for clarity fig3 is a schematic plan view illustration of the embodiment of fig1 in a latched state rotation of latching gear 146 and therefore output shaft 144 not shown is prevented as cam arm 146 is captured e g locked between the leading latch cam 120 and trailing latch cam 122 the latch cams 120 and 122 are shaped such that rotation of the latching gear 146 in either direction produces a torque that rotates the flange 118 in a direction to force further engagement of latch cams 120 and 122 with the cam arm 148 flexible spring element 158 applies clockwise torque to latching gear 148 further resisting counterclockwise rotation of the latching gear balancing cam 124 does not engage the cam arm 148 but serves to balance the pinion gear 116 flange 118 and latch cams 120 and 122 so that the drive assembly 110 cannot be easily rotated by mechanical vibrations fig4 is a schematic plan view illustration of the embodiment of fig1 in the process of beginning to unlatch drive means 114 not shown have been utilized to apply a clockwise torque to pinion gear 116 rotating flange 118 approximately 45 degrees to a point where the leading latch cam 120 no longer interferes with the cam arm 148 the interior edge of the trailing latch cam 122 is driving the latching gear 146 via contact with the cam arm 148 and latching gear 146 is now free to continue rotation in a.