Abstract: A plate check valve having a housing for mounting across a fluid passsageway to prevent reverse flow therein; a cage detachably mounted on the housing; a plurality of annular, planar, coaxial, radially spaced seat plates releasably clamped between the housing and the cage; and a plurality of axially movable, annular, planar valve plates individually related to and overlapping the spaces between the seat plates, the valve plates moving into engagement with the seat plates to prevent reverse flow through the valve and from the seat plates for normal flow through the valve.

Abstract: A four wheel, pedal driven vehicle particularly adapted for two persons seated in tandem, wherein each person alone or together can operate the vehicle by pedaling and steering. The vehicle comprises a unitary frame, a front spindle yoke assembly in combination with front handle bars and with front wheel forks of each front wheel, a steering control system in combination with the yoke assembly and rear handle bar means, a continuous drive chain assembly which is in combination with sprockets and pedals of both operator positions and which is in combination with transmission means and a rear drive assembly, whereby the drive chain can be driven from either tandem position. The vehicle has an associated body shell and cowls as well as conventional brakes, lights, etc.