Folding gooseneck trailer

Claim 2

A folding gooseneck trailer comprising: a. a main bed supported on a plurality of wheels at one end; b. extensible lifting means for raising and lowering the other end of said main bed; c. a loading bed; d. pivotable links connecting said loading bed to said other end of said main bed to permit folding and unfolding of said loading bed relative to said main bed; and e. extensible means for pivoting links to fold and unfold said loading bed, said pivoting means being interconnected to said lifting means thereby to act as stationary bracing elements during operation of said lifting means.

Claim 3

The device of claim 1 further including means for preventing operation of said pivoting means while said lifting means is bearing the weight of said trailer to insure the pivoting means remain stationary when acting as a bracing element.

Claim 4

The device according to claim 2 wherein said means for preventing operation includes a check valve in the hydraulic system to prevent fluid flow to said pivoting means when the said lifting means is bearing the weight of the trailer.

Claim 5

The device of claim 1 further including means for preventing unfolding of said loading bed when said lifting means is bearing the weight of said trailer.

Claim 6

The device according to claim 4 wherein said means for preventing unfolding includes: a. a blocking pin for preventing movement of said pivotable links in a first position; b. air lock means for moving said blocking pin from said first position to permit movement of said links; and c. check means for rendering said air lock means inoperative when said lifting means is bearing the weight of said trailer.

Claim 7

The device according to claim 5 wherein said air lock means includes an air cylinder pivoting a lever arm to which the blocking pin is connected and said check means is a check valve.

Claim 8

The device of claim 1 wherein said lifting means includes: a. a pair of double acting hydraulic bed cylinders and pistons mounted to ones of said links; b. means for selectively operating said bed cylinders; and c. ground pads connected to the pistons of said cylinders by a connecting rod whereby operation of said cylinders causes extension and retraction of said ground pads to raise and lower said other end of said main bed.

Claim 9

The device according to claim 7 wherein said bed cylinders are pivotably mounted to said links near their piston end.

Claim 10

The device of claim 1 wherein said pivotable links include a pair of compression links and a pair of tension links and said lifting means are mounted on said compression links.

Claim 11

The device of claim 1 wherein the means for pivoting includes: a. a pair of hydraulic brace cylinders and pistons mounted to said other end of the main bed; b. hook plates attached to said loading bed and adapted to rotate said loading bed between the folded and unfolded positions in response to the extension and retraction of said brace cylinder pistons.

Claim 12

The device according to claim 10 wherein said brace cylinders are single acting and said retraction is caused by the weight of said loading bed during unfolding.

Claim 13

The device of claim 1 wherein: a. said lifting means includes: i. a pair of double acting hydraulic bed cylinders and pistons mounted to ones of said links; ii. means for selectively operating said bed cylinders; and iii. ground pads connected to the pistons of said cylinders by a connecting rod whereby operation of said cylinders causes extension and retraction of said ground pads to raise and lower said other end of said main bed; and b. said means for pivoting includes: i. a pair of hydraulic brace cylinders and pistons mounted to said other end of the main bed; and ii. hook plates attached to said loading bed and adapted to rotate said loading bed between the folded and unfolded positions in response to the extension and retraction of said brace cylinder pistons said brace pistons also connected to said ground pads and rendered inoperative during operation of said bed cylinders thereby to function as said bracing element.

Claim 14

The device of claim 1 further including means for preventing accidental operation of said pivoting means while said lifting means is bearing the weight of said trailer to insure the pivoting means remains stationary when acting as a bracing element and means for preventing unfolding of said loading bed when said lifting means is bearing the weight of said trailer.

Claim 15

A folding gooseneck trailer comprising: a. a main bed supported on a plurality of wheels at one end; b. a loading bed; c. pivotable links connecting said loading bed to said other end of said main bed to permit folding and unfolding of said loading bed relative to said main bed; d. extensible lifting means for raising and lowering the other end of said main bed including a pair of double acting hydraulic bed cylinders and pistons mounted to ones of said links, means for selectively operating said bed cylinders, and ground pads connected to the pistons of said bed cylinders by a connecting rod whereby operation of said bed cylinders causes extension and retraction of said ground pads to raise and lower said other end of said main bed; e. extensible means for pivoting said links to fold and unfold said loading bed, said pivoting means being interconnected to said lifting means thereby to act as stationary bracing elements during operation of said lifting means, said pivoting means including a pair of hydraulic brace cylinders and pistons mounted to said other end of the main bed and hook plates attached to said loading bed and adapted to rotate said loading bed between the folded and unfolded positions in response to the extension and retraction of said brace cylinder pistons; f. means for preventing operation of said pivoting means while said lifting means is bearing the weight of said trailer to insure the pivoting means remain stationary when acting as a bracing element; and g. means for preventing unfolding of said loading bed when said liftIng means is bearing the weight of said trailer.

Claim 16

A folding gooseneck trailer comprising: a. a main bed supported on a plurality of wheels at one end; b. a loading bed; c. pivotable links connecting said loading bed to said other end of said main bed to permit folding and unfolding of said loading bed relative to said main bed; d. extensible lifting means for raising and lowering the other end of said main bed including a pair of double acting hydraulic bed cylinders and pistons mounted to ones of said links, means for selectively operating said bed cylinders, and ground pads connected to the pistons of said bed cylinders by a connecting rod whereby operation of said bed cylinders causes extension and retraction of said ground pads to raise and lower said other end of said main bed; e. extensible means for pivoting said links to fold and unfold said loading bed, said pivoting means being interconnected to said lifting means thereby to act as stationary bracing elements during operation of said lifting means, said pivoting means including a pair of hydraulic brace cylinders and pistons mounted to said other end of the main bed and hook plates attached to said loading bed and adapted to rotate said loading bed between the folded and unfolded positions in response to the extension and retraction of said brace cylinder pistons; f. means for preventing operation of said pivoting means while said lifting means is bearing the weight of said trailer to insure the pivoting means remain stationary when acting as a bracing element; and g. means for preventing unfolding of said loading bed when said liftIng means is bearing the weight of said trailer.