is rotated further counter clockwise from this neutral position spring member 86 is loaded in tension and exerts a steadily increasing rotational biasing force urging the cam member clockwise eventually as cam member is turned further counter clockwise cam follower portions 62 64 contact mechanical stops 96 98 on cam member 68 the latching mechanism illustrated in fig4 and 5 has a number of distinct advantages first spring member 86 provides two favored positions for cam member 68 corresponding to the neutral positions described above these favored positions are created with a single spring member and without the need for sliding contact between parts that can cause undesirable particulates secondly spring member 86 provides a rotational biasing force urging cam member 68 toward either of the favored positions depending on the rotational position of cam member 68 in operation cam member 68 experiences about 90 degrees of rotational travel range spring member 86 provides a rotational biasing force over nearly the entire range exerting no biasing force only when cam member 68 is at the mid point of its rotational range and when it is at either of the two favored positions thus the effective rotational range where spring member 86 provides a rotational biasing force urging cam member 68 toward its favored positions is nearly 45 degrees in each direction finally as explained above spring member 86 provides a biasing force resisting rotation of cam member 68 beyond each of its favored positions as a result when cam member 68 is rotated to either of its favored positions it is decelerated in a controlled fashion by spring member 86 as it moves past the favored position and its momentum is absorbed once the momentum has been absorbed spring member 86 contracts pulling cam member.