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US 5,181,872 AGranted
Emergency propulsion device
OwnerKenneth Greeninventor
Life of this patent
Estimating the term…
Abstract
The device is an alternative to the conventional paddle or oars, and comprises a collapsible scoop and a handle-shaft. The scoop has top and bottom panels 14,16, hinged together along one edge 18, and side-panels. The side-panels 20 are foldable, and allow the scoop to open and close. When the handle is pushed, the scoop opens out by the action of hydrodynamic forces; when pulled, the scoop collapses. The scoop is made from a one-piece blank cut from stiff plastic sheet. The hinges are formed by locally creasing the plastic material.
Claims11
Auxiliary propulsion device for a boat, wherein:
- the device includes a collapsible scoop, and a shaft-handle;
- the arrangement is such that a person in the boat may apply a thrust-force through the handle to the scoop, in direction to the rear of the boat, the reaction to said thrust-force being effective to propel the boat forwards;
- the scoop comprises a top panel, a bottom panel, and at least one connecting panel;
- the top and bottom panels have front and rear edges;
- the scoop includes a main hinge, upon which the top and bottom panels are hinged, and which is operatively connected between the rear edges of the top and bottom panels;
- the scoop is capable of adopting two conditions, a wide open condition and a collapsed condition;
- in the wide open condition, the top and bottom panels are pivoted apart about the main hinge, and in the collapsed condition the top and bottom panels are pivoted together about the main hinge;
- in the wide open condition, the top and bottom panels present a comparatively large rearward-facing area to the water, said area being in the plane lying transverse to the direction of thrust;
- in the collapsed condition, the top and bottom panels present a comparatively much smaller area to the water in said transverse plane;
- the arrangement of the scoop is such that the scoop collapses to the closed condition upon being drawn through the water in the opposite direction to the direction of thrust;
- the arrangement of the scoop is such that the at-least-one connecting panel, at least in the wide open condition, lies substantially edge-on to the direction of thrust, whereby the connecting panel acts as a rudder to prevent the scoop deviating from the direction of thrust;
- the at-least-one connecting panel comprises an upper and a lower portion;
- the upper portion of the connecting panel is hinged to the top panel about an upper hinge;
- the lower portion of the connecting panel is hinged to the bottom panel about a lower hinge;
- the two portions of the connecting panel are hinged together about a side hinge;
- the top panel, the bottom panel, and the upper and lower portions of the connecting panel, are all of a substantially stiff, non-flexible, plastic sheet material;
- all the said hinges are living hinges, being hinges of the kind formed by locally thinning the sheet material;
- one of either the top panel or the bottom panel is provided with a coupling means for coupling the shaft-handle to that one panel;
- the said coupling means is so arranged that, in operation of the device, the shaft-handle and that one panel are coupled together in such a manner that the shaft-handle can undergo substantially no pivoting or any other movement relative to that one panel during the said relative pivoting movement of the two panels, from the wide open condition to the collapsed condition of the scoop.
16 more elements
Auxillary propulsion device for a boat, wherein:
- the device includes a shaft-handle and a scoop;
- the shaft-handle is adapted to be held in the hand of a person using the device to propel a boat;
- the scoop comprises a single, unitary piece of stiff sheet plastic material;
- the single piece of plastic material is provided with creases comprising local thinning of the said plastic material, whereby the creases comprise hinges of the kind known as living hinges;
- the disposition of the creases in the piece of plastic material is such as to define four panels, being a top panel, a bottom panel, and left and right side panels of the scoop;
- the disposition of the creases in the piece of plastic material is such as to divide the left and right side panels into respective upper and lower portions;
- the disposition of the creases in the piece of plastic material is such as to provide a main hinge between the top panel and the bottom panel;
- left and right upper hinges connecting the upper portions of the left and right side panels to the top panel;
- left and right lower hinges connecting the lower portions of the left and right side panels to the bottom panel;
- and left and right side hinges connecting the upper and lower portions of the left and right side panels;
- the single piece of plastic material is, in substance, rigid and inflexible apart from being foldable or pivotable about the said living hinges between the panels;
- one of the top and bottom panels of the single piece of plastic material includes a coupling means for coupling the shaft-handle to that one panel;
- the said coupling means is so arranged that, in operation of the device, the shaft-handle and that one panel are coupled together in such a manner that the shaft-handle can undergo substantially no pivoting or any other movement relative to that one panel, during relative hinging movement of the top and bottom panels.
10 more elements
Dependencies are inferred from the claim text.