Abstract: Designs for multiple segment lobe pumps are shown. The designs include pumps using rotors having two lobes to a plurality of lobes and segments that include two segments to a plurality of segments. Designs for both vertical, or straight walled conventional lobed rotors, as well as helical lobe rotors are shown. The designs are applicable to a variety of rotors and number of segments. In one particular case the designs enable a three lobe helical pump. Designs are also shown for separation plates used between the multiple segments. The separation float between the pairs of lobes in a segment and can also have a fixed position between the lobes by inclusion of end pieces that enable clamping of the separation plates in position.

Abstract: Designs for multiple segment lobe pumps are shown. The designs include pumps using rotors having two lobes to a plurality of lobes and segments that include two segments to a plurality of segments. Designs for both vertical or straight walled conventional lobed rotors as well as helical lobe rotors are shown. The designs are applicable to a variety of rotors and number of segments. In one particular case the designs enable a three lobe helical pump.

Abstract: Designs for multiple segment lobe pumps are shown. The designs include pumps using rotors having two lobes to a plurality of lobes and segments that include two segments to a plurality of segments. Designs for both vertical, or straight walled conventional lobed rotors, as well as helical lobe rotors are shown. The designs are applicable to a variety of rotors and number of segments. In one particular case the designs enable a three lobe helical pump. Designs are also shown for separator plates used between the multiple segments. The separator float between the pairs of lobes in a segment and can also have a fixed position between the lobes by inclusion of end pieces that enable clamping of the separator plates in position.

Abstract: Designs for multiple segment lobe pumps are shown. The designs include pumps using rotors having two lobes to a plurality of lobes and segments that include two segments to a plurality of segments. Designs for both vertical or straight walled conventional lobed rotors as well as helical lobe rotors are shown. The designs are applicable to a variety of rotors and number of segments. In one particular case the designs enable a three lobe helical pump.

Abstract: A highly efficient watercraft propulsion system that relies on a positive displacement pump to generate a water jet. The pump is fully submerged at all times and its inlet is positioned so as to cause water to be forced into the pump as the watercraft moves through the water. The pump is preferably combined with a variable area pump opening which is configured, positioned and oriented so as to maximize the hydraulic reaction between the water jet stream and the surrounding body of water.

Abstract: A highly efficient watercraft propulsion system that operates continually submerged and relies on a non-circular variable area pump discharge opening which is configured, positioned and oriented so as to maximize the hydraulic reaction between the high velocity water jet stream and the surrounding body of water and is driven by a positive displacement pump.

Abstract: Rack means for mounting and carring devices such as two-wheeled vehicles (e.g., bicycles) on engine-powered vehicles such as automobiles includes structures for clamping the rack between the trunk and trunk lid, the engine well and engine hood, or between some other opening on the automobile and a closure appended to that opening. Racks of this kind permit carrying two or more bicycles in side-by-side relationship with minimum abrasion of one against another.