Ratchet-type lift jack unit and lift method for camper bodies and the like

Claim 2

In a lift jack assembly for raising and lowering a camper body or the like, a ratchet-type jack unit comprising: telescoping outer and inner leg sections, said inner leg section having a series of spaced notches arranged longitudinally thereof, locking means positively but releasably urged into engagement with said inner leg section in a locking position, said locking means being movable to a released position under the weight of the inner leg section to allow for a free-dropping movement of said inner leg section, said locking means being biased to automatically return to locking engagement with said inner leg section against further movement relative to said outer leg section when a load is applied in a direction urging said inner leg section upwardly with respect to said outer leg section and, handle means having a yoke at one end adapted to extend around said outer leg section, there being attachment means between said yoke and said outer leg section to pivotally attach the yoke to oppositely disposed portions of the outer leg section and a ratchet supported on the yoke terminating in a dog adapted to insert into a selected one of said notches whereby a downward force applied to the handle urges said outer leg section upwardly relative to the inner leg section, said locking means automatically locking said leg sections at the end of each downstroke of the handle.

Claim 3

In a lift jack assembly as set forth in claim 1 wherein said attachment means is in the form of a pair of oppositely disposed slots on said outer leg section and a pair of inturned aligned pins on said yoke adapted to insert into said pair of slots.

Claim 4

In a lift jack assembly as set forth in claim 2 wherein said pair of slots are formed in a C-type clamp secured to the lower end of the outer leg section, said slots being inclined upwardly toward said handle.

Claim 5

In a lift jack assembly as set forth in claim 2 wherein said clamp has a pair of outwardly projecting lugs and a cross pin through the lugs for providing a pivotal support for the locking means above the lugs.

Claim 6

In a lift jack assembly as set forth in claim 2 wherein said handle is inclined on an upwardly directed angle form the back of the yoke.

Claim 7

In a lift jack assembly as set forth in claim 1 wherein said ratchet member has a forked upper end pivotally connected to the side arms of the yoke, and bias means to urge the dog into each notch.

Claim 8

In a lift jack assembly for raising and lowering a camper body or the like, a ratchet-type lift jack unit for at least one corner of the camper body, said lift jack unit comprising: outer and inner telescoping tubular leg sections, said outer leg section having a lower end portion with a slot and a pair of spaced projections extending outwardly from said outer leg section, said inner leg section having a series of vertically spaced notches aligned with the slot of the outer leg section, a generally L-shaped positive locking lever pivotally mounted between said lugs, said lever having an inturned dog in the lower end thereof, said dog being positively moved through said slot successively into each notches as the leg sections are moved axially relative to one another to lock in the outer and inner leg sections against relative axial movement, said locking lever dog being inwardly and downwardly inclined for automatically releasing the inner leg section from the outer leg section for a free-dropping movement as the camper body is raised, said locking the lever being spring-biased to automatically move into the locking position, and a demountable lift handle assembly having a yoke at one end, one of the lower end portion of said outer leg section and said yoke having a pair of aligned pins and the other of said lower end portion and yoke having a pair of opposed slots adapted to receive said pins to releasably connect said yoke to said outer leg section for pivotal movement about the axis of said pins, a handle extending from the back of the yoke and a ratchet member depending from said yoke and terminating in a ratchet dog shaped to removably insert into the notches in the inner leg section and as the handle is moved in a downward stoke and an upward force is imparted to the outer leg section through the pins with the locking lever dog entering the next notch in the inner leg section.

Claim 9

In a lift jack assembly for raising and lowering a camper body or the like, a ratchet-type lift jack unit for at least one corner of the camper body, said lift jack unit comprising: outer and inner telescoping tubular leg sections, said outer leg section having a lower end portion with a slot and a pair of spaced projections extending outwardly from said outer leg section, said inner leg section having a series of vertically spaced notches aligned with the slot of the outer leg section, a generally L-shaped positive locking lever pivotally mounted between said lugs, said lever having an inturned dog in the lower end thereof, said dog being positively moved through said slot successively into each notches as the leg sections are moved axially relative to one another to lock in the outer and inner leg sections against relative axial movement, said locking lever dog being inwardly and downwardly inclined for automatically releasing the inner leg section from the outer leg section for a free-dropping movement as the camper body is raised, said locking the lever being spring-biased to automatically move into the locking position, and a demountable lift handle assembly having a yoke at one end, one of the lower end portion of said outer leg section and said yoke having a pair of aligned pins and the other of said lower end portion and yoke having a pair of opposed slots adapted to receive said pins to releasably connect said yoke to said outer leg section for pivotal movement about the axis of said pins, a handle extending from the back of the yoke and a ratchet member depending from said yoke and terminating in a ratchet dog shaped to removably insert into the notches in the inner leg section and as the handle is moved in a downward stoke and an upward force is imparted to the outer leg section through the pins with the locking lever dog entering the next notch in the inner leg section.

Claim 10

In a lift jack assembly in which a plurality of lift jack units are attached to a camper body for raising and lowering same, each said lift jack unit comprising telescoping outer and inner leg sections, each of said telescoping outer sections including locking means positively but releasably urged into locking engagement with its associated inner leg section, said locking means being movable to a released position under the weight of the inner leg section to allow for a free-dropping movement of said inner leg section, said locking means being biased to automatically return to locking engagement with said inner leg section against further movement relative to said outer leg section when a load is applied in a direction urging said inner leg section upwardly with respect to said outer leg section, a demountable handle actuated means supported for pivotal movement on said outer leg section, said handle actuated means including a yoke adapted to extend around said outer leg section, there being releasable attachment means on said yoke and said outer leg section to pivotally attach the yoke to oppositely disposed portions of the outer leg section.

Claim 11

In a lift jack assembly in which a plurality of lift jack units are attached to a camper body for raising and lowering same, each said lift jack unit comprising telescoping outer and inner leg sections, each of said telescoping outer sections including locking means positively but releasably urged into locking engagement with its associated inner leg section, said locking means being movable to a released position under the weight of the inner leg section to allow for a free-dropping movement of said inner leg section, said locking means being biased to automatically return to locking engagement with said inner leg section against further movement relative to said outer leg section when a load is applied in a direction urging said inner leg section upwardly with respect to said outer leg section, a demountable handle actuated means supported for pivotal movement on said outer leg section, said handle actuated means including a yoke adapted to extend around said outer leg section, there being releasable attachment means on said yoke and said outer leg section to pivotally attach the yoke to oppositely disposed portions of the outer leg section.