Abstract: An automatically-locking bypass valve (10) of the type including a valve body (12), an inner member (11) in sliding engagement with the valve body (12) and having a bypass opening (48), the valve body (12) and inner member (11) having first and second vacuum-reactive surfaces (18a and 18b respectively), and a spring (60) between the valve body (12) and the inner member (11) against which the vacuum-reactive surfaces (18a and 18b respectively) move axially relative to each other. The valve body (12) has a guide (26) and the inner member (11) has a guide-follower (50) which is (a) slidably engaged with the guide (26) in one rotational alignment with the valve body (12) in a normal operating range of relative axial positions of the valve body (12) and inner member (11) and (b) out of sliding engagement with the guide (26) beyond such normal operating range.

Abstract: An improved skirt for use with an automatic or robotic pool cleaner head comprising at least one or a row of double-hinged flaps, each of the flaps comprising a receiving member affixed to the pool cleaner head, an upper articulating member pivotally coupled to the receiving member, and a lower articulating member pivotally coupled to the upper articulating member. The pivotally connected members form upper and lower hinges which allow free radial movement upward to, but not beyond, the bottom surface of the pool cleaning head, and further allow the cleaning head to navigate uneven surfaces or pieces of debris while maintaining effective suction.