Boat lifting device

Claim 1

A device for raising a boat onto a vehicle aNd for lowering the boat from the vehicle, the vehicle having a generally horizontal support means spaced at a support height above the ground, the support means having spaced upper and lower rear portions; the boat having a bow, a stern, gunwales, and a centre of gravity disposed adjacent a central vertical plane extending between the bow and stern, the central plane being adapted to coincide generally with a central vertical plane of the vehicle when the boat is carried on the vehicle, the device including: a. a hinged framework having a pair of spaced, similar, generally L-shaped side members, each L-shaped side member having: i. a first portion having inner and outer ends, the outer end being adapted to be hinged to the lower rear portion of the support means so as to permit swinging about a horizontal hinge axis disposed transversely of the vehicle, the first portion having a length greater than spacing between the upper and lower rear portions of the support means, ii. a second portion having inner and outer ends, the inner ends of the first and second portions being secured together at a frame corner so that the portions are inclined to each other at a frame angle, the second portion having a length greater than spacing between the stern and the centre of gravity of the boat, the hinged framework further including: iii. a transverse tie rod extending between the L-shaped side members so as to secure the side members together so that the first and second portion of each L-shaped side member are disposed in first and second planes respectively inclined at the frame angle so as to form an essentially rigid framework that can hinge about the hinge axis as a single unit, iv. first and second pulleys mounted on the framework and journalled for rotation within generally vertical planes, the pulleys being positioned on the framework so that when the boat gunwales are adjacent the second members of the framework with the stern thereof adjacent the frame corner of the framework, the first pulley is positioned forward of the centre of gravity of the boat and the second pulley is positioned generally adjacent the centre of gravity of the boat, the device further including: b. an aligned spaced pulley pair journalled for rotation within a vertical plane at a position adjacent the upper rear portion of the vehicle support means, c. reversible winch means secured to the vehicle, d. a flexible tension link having inner and outer ends, the outer end adapted to be secured to the boat at a position forward of the centre of gravity thereof, the inner end cooperating with the winch, the link passing from the boat over the first pulley, around the second pulley and between the pulley pair to the winch means, e. hinge means adapted to be secured to the stern of the boat and to cooperate releasably with the tie rod at the frame corner of the framework to permit swinging of the boat thereabouts, f. boat engaging means on the second portions of the frame member to engage the boat when the gunwales are adjacent the second portions to reduce movement between the boat and the framework, g. releasable means to retain the hinged framework in the raised position on the vehicle, so that when the frame is in a lowered position and the boat is positioned upright with the central plane thereof generally normal to the hinge axis, the bow remote from the vehicle and the stern adjacent the frame corner with the hinge means of the boat cooperating with the tie rod of the framework, when the winch takes in the flexible link the bow of the boat is raised upwards as the boat rotates about the tie rod until the boat gunwales are brought adjacent the second portions of the framework, the boat being held thereagainst by link tension, and continued taking in of the link rotates the framework through approximately 90* about the hinge axis thereof to a fully raised position so that the boat is lifted above and forward of the upper rear portion of the supporting means, the boat simultaneously rotating about the stern thereof to assume an inverted position supported upon the vehicle, control of the boat being maintained throughout by reversal of the winch means as the boat centre of gravity passes forward of the pulley pair.

Claim 2

A device for raising a boat onto a vehicle aNd for lowering the boat from the vehicle, the vehicle having a generally horizontal support means spaced at a support height above the ground, the support means having spaced upper and lower rear portions; the boat having a bow, a stern, gunwales, and a centre of gravity disposed adjacent a central vertical plane extending between the bow and stern, the central plane being adapted to coincide generally with a central vertical plane of the vehicle when the boat is carried on the vehicle, the device including: a. a hinged framework having a pair of spaced, similar, generally L-shaped side members, each L-shaped side member having: i. a first portion having inner and outer ends, the outer end being adapted to be hinged to the lower rear portion of the support means so as to permit swinging about a horizontal hinge axis disposed transversely of the vehicle, the first portion having a length greater than spacing between the upper and lower rear portions of the support means, ii. a second portion having inner and outer ends, the inner ends of the first and second portions being secured together at a frame corner so that the portions are inclined to each other at a frame angle, the second portion having a length greater than spacing between the stern and the centre of gravity of the boat, the hinged framework further including: iii. a transverse tie rod extending between the L-shaped side members so as to secure the side members together so that the first and second portion of each L-shaped side member are disposed in first and second planes respectively inclined at the frame angle so as to form an essentially rigid framework that can hinge about the hinge axis as a single unit, iv. first and second pulleys mounted on the framework and journalled for rotation within generally vertical planes, the pulleys being positioned on the framework so that when the boat gunwales are adjacent the second members of the framework with the stern thereof adjacent the frame corner of the framework, the first pulley is positioned forward of the centre of gravity of the boat and the second pulley is positioned generally adjacent the centre of gravity of the boat, the device further including: b. an aligned spaced pulley pair journalled for rotation within a vertical plane at a position adjacent the upper rear portion of the vehicle support means, c. reversible winch means secured to the vehicle, d. a flexible tension link having inner and outer ends, the outer end adapted to be secured to the boat at a position forward of the centre of gravity thereof, the inner end cooperating with the winch, the link passing from the boat over the first pulley, around the second pulley and between the pulley pair to the winch means, e. hinge means adapted to be secured to the stern of the boat and to cooperate releasably with the tie rod at the frame corner of the framework to permit swinging of the boat thereabouts, f. boat engaging means on the second portions of the frame member to engage the boat when the gunwales are adjacent the second portions to reduce movement between the boat and the framework, g. releasable means to retain the hinged framework in the raised position on the vehicle, so that when the frame is in a lowered position and the boat is positioned upright with the central plane thereof generally normal to the hinge axis, the bow remote from the vehicle and the stern adjacent the frame corner with the hinge means of the boat cooperating with the tie rod of the framework, when the winch takes in the flexible link the bow of the boat is raised upwards as the boat rotates about the tie rod until the boat gunwales are brought adjacent the second portions of the framework, the boat being held thereagainst by link tension, and continued taking in of the link rotates the framework through approximately 90* about the hinge axis thereof to a fully raised position so that the boat is lifted above and forward of the upper rear portion of the supporting means, the boat simultaneously rotating about the stern thereof to assume an inverted position supported upon the vehicle, control of the boat being maintained throughout by reversal of the winch means as the boat centre of gravity passes forward of the pulley pair.