Automatic locking clutch with sliding clutch ring

In a vehicle clutch of the type having concentric and spaced apart driving and driven members, including a clutch ring in engagement with one of the members and urgeable into simultaneous engagement with the other member, the improvement comprising:

• (a) a first cam member rigidly fixed to the vehicle and nonrotatable with respect to the driving and driven members for all rotational speeds therebetween;
• (b) a second cam member slidably movable around said first cam member whenever the clutch ring is simultaneously engaged to the driving and driven members;
• and
• (c) a cam follower abutting the clutch ring and in cam engagement with said first cam member and movable axially apart from said first cam member into a cammed engagement with said second cam member thereby urging the clutch ring into simultaneous engagement with the driving and driven member whenever the driving member rotates with respect to the driven member.