Hand trucks

Claim 2

A hand truck comprising a driving chassis having a front end portion and a rear end portion and a telescopic tube arranged therebetween so as to allow the distance between said front and rear end portions to be varied, front wheel means mounted on said front end portion and rear wheel means mounted on said rear end portion so as to be operable to support the driving chassis on the ground with said telescopic tube substantially parallel therewith, an article carrier frame element pivotally secured to said front end portion of said chassis so as to be pivotal relative to the ground supported driving chassis between an upright loading position substantially perpendicular to the driving chassis and a tilted transport position in which the carrier frame is inclined rearwardly over the carrier chassis so as to form an actue angle therewith, carrier frame element support means interposed between said carrier frame element and said driving chassis so as to be operable to support the frame element in its said transport position relatively to the driving chassis, and a connector rod hinged at its opposite ends to said rear chassis end portion and a point of said frame element above the pivoting axis of the frame element, respectively, so as to be operable to cause said telescopic tube to expand and said rear chassis end portion to be displaced away from said front chassis end portion in direct response to the carrier frame element and the driving chassis being mutually pivoted to diminish the angle therebetween, while correspondingly being operable to cause said telescopic tube to contact and said rear chassis end portion to be displaced towards said front chassis end portion in direct response to the carrier frame element and the driving chassis being mutually pivoted to enlarge the angle between them.

Claim 3

A hand truck according to claim 1, in which said distance control means comprise a connector rod hinged at its opposite ends to said rear chassis end portion and a point of said frame element above the pivoting axis of the frame element, respectively.

Claim 4

A hand truck according to claim 1 and comprising locking means for releasably locking together the driving chassis and the carrier frame element in the horizontal transport position of said element.

Claim 5

A hand truck according to claim 1, in which said carrier frame element support means comprises a telescopic tube system interposed between a point adjacent the upper end of the carrier frame element above said point in which said connector rod is hinged to the frame element and a point of said rear end portion of the driving chassis, the telescopic tube system being length variable between an expanded position corresponding to the carrier frame assuming its upright loading position and a shortened pressure absorbing position corresponding to the frame element assuming its inclined transport position.

Claim 6

A hand truck according to claim 5, and comprising a handle structure releasably associated with said carrier frame element so as to normally extend therealong from a lower end portion adjacent the lower end of the frame element to an upper end portion adjacent the upper end of the frame element, said upper end portion being provided with handle means, the upper end portion of the carrier frame element comprising means for receiving and holding said lower end portion of said handle structure upon release of this structure from its normal position on the carrier frame element so as to be operable to hold the handle structure in a position in which it projects from the upper end of the carrier frame element generally orthogonally to the plane of the carrier frame element, so as to project upwardly when the frame element assumes its horizontal transport position.

Claim 7

A hand truck comprising a driving chassis having a front end portion and a rear end portion, front wheel shaft means connected to said front end portion and provided with front support wheel means, rear wheel shaft means connected to said rear end portion and provided with rear support wheel means, an article carrier frame element pivotally secured to said front end portion of said chassis so as to be pivotal relatively to the entire driving chassis between an upright loading position and a rearwardly inclined transport position, carrier frame element support means interposed between said carrier frame element and said driving chassis so as to be operable to support the frame element in its said transport position relatively to the driving chassis, said front and rear end portions of said chassis being interconnected by connector means allowing the distance between the front and the rear wheel shaft means to be varied, and distance control means operatively connected with said carrier frame element and said driving chassis so as to cause the distance between the front and rear wheel shaft means to increase in response to the carrier frame element being tilted rearwardly relatively to the driving chassis towards its transport position and to cause the side distance to be decreased in response to said carrier frame element being tilted forwardly relatively to the driving chassis its said upright position, in which said carrier frame element support means are releasable so as to allow, when released, said carrier frame element to be tilted further downwardly and rearwardly from said inclined transport position to a generally horizontal transport position supported on said driving chassis, said distance control means further being responsive to tilting of the carrier frame element between said inclined and said generally horizontal transport positions so as to be operable to increase the distance between said front and rear wheel shaft means to a relative maximum in response to the carrier frame element being tilted down into its said generally horizontal transport position.

Claim 8

A hand truck comprising a driving chassis having a front end portion and a rear end portion, front wheel shaft means connected to said front end portion and provided with front support wheel means, rear wheel shaft means connected to said rear end portion and provided with rear support wheel means, an article carrier frame element pivotally secured to said front end portion of said chassis so as to be pivotal relatively to the entire driving chassis between an upright loading position and a rearwardly inclined transport position, carrier frame element support means interposed between said carrier frame element and said driving chassis so as to be operable to support the frame element in its said transport position relatively to the driving chassis, said front and rear end portions of said chassis being interconnected by connector means allowing the distance between the front and the rear wheel shaft means to be varied, and distance control means operatively connected with said carrier frame element and said driving chassis so as to cause the distance between the front and rear wheel shaft means to increase in response to the carrier frame element being tilted rearwardly relatively to the driving chassis towards its transport position and to cause the side distance to be decreased in response to said carrier frame element being tilted forwardly relatively to the driving chassis its said upright position, in which said carrier frame element support means are releasable so as to allow, when released, said carrier frame element to be tilted further downwardly and rearwardly from said inclined transport position to a generally horizontal transport position supported on said driving chassis, said distance control means further being responsive to tilting of the carrier frame element between said inclined and said generally horizontal transport positions so as to be operable to increase the distance between said front and rear wheel shaft means to a relative maximum in response to the carrier frame element being tilted down into its said generally horizontal transport position.

Claim 9

A hand truck comprising a driving chassis having a front end portion and a rear end portion, front wheel shaft means connected to said front end portion and provided with front support wheel means, rear wheel shaft means connected to said rear end portion and provided with rear support wheel means, an article carrier frame element pivotally secured to said front end portion of said chassis so as to be pivotal relatively to the entire driving chassis between an upright loading position and a rearwardly inclined transport position, carrier frame element support means interposed between said carrier frame element and said driving chassis so as to be operable to support the frame element in its said transport position relatively to the driving chassis, said front and rear end portions of said chassis being interconnected by connector means allowing the distance between the front and the rear wheel shaft means to be varied, and distance control means operatively connected with said carrier frame element and said driving chassis so as to cause the distance between the front and rear wheel shaft means to increase in response to the carrier frame element being tilted rearwardly relatively to the driving chassis towards its transport position and to cause the said distance to be decreased in response to said carrier frame element being tilted forwardly relatively to the driving chassis its said upright position, in which said carrier frame element support means comprises a telescopic tube system interposed between a point adjacent the upper end of the carrier frame element and a point of said rear end portion of the driving chassis, the telescopic tube system being length variable between an expanded position corresponding to the carrier frame assuming its upright loading position and a shortened pressure absorbing position corresponding to the frame element assuming its inclined transport position, in which one end of said telescopic tube system is releasably connected to the respective said point so as to allow, when released, the carrier frame element to be folded together with said driving chassis.

Claim 10

A hand truck comprising a driving chassis having a front end portion and a rear end portion, front wheel shaft means connected to said front end portion and provided with front support wheel means, rear wheel shaft means connected to said rear end portion and provided with rear support wheel means, an article carrier frame element pivotally secured to said front end portion of said chassis so as to be pivotal relatively to the entire driving chassis between an upright loading position and a rearwardly inclined transport position, carrier frame element support means interposed between said carrier frame element and said driving chassis so as to be operable to support the frame element in its said transport position relatively to the driving chassis, said front and rear end portions of said chassis being interconnected by connector means allowing the distance between the front and the rear wheel shaft means to be varied, and distance control means operatively connected with said carrier frame element and said driving chassis so as to cause the distance between the front and rear wheel shaft means to increase in response to the carrier frame element being tilted rearwardly relatively to the driving chassis towards its transport position and to cause the said distance to be decreased in response to said carrier frame element being tilted forwardly relatively to the driving chassis its said upright position, in which said carrier frame element support means comprises a telescopic tube system interposed between a point adjacent the upper end of the carrier frame element and a point of said rear end portion of the driving chassis, the telescopic tube system being length variable between an expanded position corresponding to the carrier frame assuming its upright loading position and a shortened pressure absorbing position corresponding to the frame element assuming its inclined transport position, in which one end of said telescopic tube system is releasably connected to the respective said point so as to allow, when released, the carrier frame element to be folded together with said driving chassis.