Elevatable trailer mechanism

Claim 2

In an elevatable trailer; a frame having a forward end and opposite sides; bell crank arms pivotally mounted on said frame on horizontal axis at opposite sides of said frame; wheels rotatably mounted on said bell crank arms in spaced relation to said horizontal axis; cantilever springs fixed to said bell crank arms and having shackle portions extending a substantial distance upwardly from said horizontal axis; tension rods pivotally coupled to said shackle portions; said tension rods extending towards said forward end of said frame; a cross bar having opposite ends pivotally coupled to said tension rods; a tongue coupled to said cross bar and having a forward end extending beyond said forward portion of said frame; a hitch coupled to said forward end of said tongue; a tongue guide carried by said forward portion of said frame; said tongue reciprocally mounted to move to forward and rearward positions relative to said tongue guide; and releasable latch means disposed to lock said tongue in said forward position for holding said bell crank arms in a pivoted position wherein said frame and said horizontal axis are in elevated position.

Claim 3

The invention as defined in claim 1 wherein said tongue is provided with upper and lower services; said tongue guide having a first plurality of horizontally spaced apart rollers engaging said upper portion of said tongue; said tongue guide having a second plurality of horizontally spaced apart rollers engaging said lower surface of said tongue.

Claim 4

The invention as defined in claim 1 wherein intermediate levers pivotally interconnect said cross bar and said tension rod; each intermediate lever having one end pivotally coupled to said frame; each lever having another end pivotally coupled to said cross bar; a respective one of said tension rods pivotally coupled to one of said levers at a location between said ends thereof.

Claim 5

The invention as defined in claim 3 wherein said tongue guide is provided with a first guide means affixed to said tongue; said forward portion of said frame having inclined guide means extending upwardly at an angle to the horizontal and towards said forward portion of said frame; said inclined guides means engagable with said first guide means and slidable forwardly and rearwardly relative thereto for elevating and lowering said forward portion of said frame relative to said tongue.

Claim 6

The invention as defined iN claim 4 wherein said latch means comprises releasable spring loaded hook means pivotally coupled to said forward portion of said frame and adapted to engage and lock said tongue in said forward position; a spring having one end fixed to said hook means; said spring having an opposite end; a manually operable handle coupled to said opposite end of said spring; and a holding bracket on said frame having a pair of spaced apart detent portions adapted to hold said spring in either of two positions tending to pivot said hook means into and out of engagement with said cross bar; said hook means having a hook portion adapted to engage said cross bar and hold it in a forward position.

Claim 7

The invention as defined in claim 5 wherein said cross bar is provided with a lug thereon; said hook means having a notch engageable with said lug for holding said tongue in said forward position relative to said frame.

Claim 8

The invention as defined in claim 1 wherein means is provided for locking said wheels against rotation relative to said bell crank arms.

Claim 9

The invention as defined in claim 1 wherein a pair of said bell crank arms and a pair of said springs are disposed at each of said opposite sides of said frame; said shackle portions pivotally coupled to said tension rods; lever and linkage means coupling said shackle portions to said tension rods; said lever and linkage means each comprising a pair of scissor levers; each scissor lever having upper and lower ends and an intermediate portion between said upper and lower ends; said intermediate portions of said scissor levers pivotally connected together; said lower end of one of said scissor levers pivotally mounted on said frame; said lower end of the other one of said pair of scissor levers pivotally coupled to said tension rod; and a pair of second tension rods; each one of said pair of said second tension rods interconnecting one shackle portion of one of said pair of contilever springs and one of said upper ends of one of said pair of scissor levers.

Claim 10

In an elevatable trailer mechanism; a frame having a forward end opposite sides; bell crank arms pivotally mounted on said frame on horizontal axes at opposite sides of said frame; wheels rotatably mounted on said bell crank arms in spaced relation to said horizontal axes; cantilever springs fixed to said bell crank arms and having shackle portions extending a substantial distance upwardly from said horizontal axes; tension rods pivotally coupled to said shackle portions; said tension rods extending towards said forward end of said frame; a cross bar having opposite ends pivotally coupled to said tension rods; means pivotally connecting said tension rods to said cross bar; a tongue coupled to said cross bar and having a forward end extending beyond said forward portion of said frame; a hitch coupled to said forward end of said tongue; a tongue guide carried by said forward portion of said frame; said tongue reciprocally mounted to move to forward and rearward positions relative to said frame; said tongue guide comprising at least one pair of parallel links pivotally interconnecting said forward portion of said frame and said tongue to allow relative elevating and lowering of said forward portion of said frame relative to said tongue corresponding respectively with rearward and forward movement of said tongue relative to said forward portion of said frame; and releasable latch means disposed to lock said tongue in said forward portion for holding said bell crank arms in a pivoted position wherein said frame and said horizontal axes are in elevated position.

Claim 11

In an elevatable trailer mechanism; a frame having a forward end opposite sides; bell crank arms pivotally mounted on said frame on horizontal axes at opposite sides of said frame; wheels rotatably mounted on said bell crank arms in spaced relation to said horizontal axes; cantilever springs fixed to said bell crank arms and having shackle portions extending a substantial distance upwardly from said horizontal axes; tension rods pivotally coupled to said shackle portions; said tension rods extending towards said forward end of said frame; a cross bar having opposite ends pivotally coupled to said tension rods; means pivotally connecting said tension rods to said cross bar; a tongue coupled to said cross bar and having a forward end extending beyond said forward portion of said frame; a hitch coupled to said forward end of said tongue; a tongue guide carried by said forward portion of said frame; said tongue reciprocally mounted to move to forward and rearward positions relative to said frame; said tongue guide comprising at least one pair of parallel links pivotally interconnecting said forward portion of said frame and said tongue to allow relative elevating and lowering of said forward portion of said frame relative to said tongue corresponding respectively with rearward and forward movement of said tongue relative to said forward portion of said frame; and releasable latch means disposed to lock said tongue in said forward portion for holding said bell crank arms in a pivoted position wherein said frame and said horizontal axes are in elevated position.