Tag wheel lift

Claim 2

In a tag wheel lift for a truck or the like having a chassis, drive wheels at each side of said chassis, mounting means including an axle for driving said drive wheels, leaf springs attached to said mounting means for supporting said chassis from said drive wheels, tag wheels at each side of said chassis and spaced lonGitudinally from said drive wheels, means for mounting said tag wheels for rotation and leaf springs attached to said tag wheel mounting means for supporting said chassis from said tag wheels when in use, the improvement including: spring seat means pivotally mounted at each side of said chassis and disposed between said first mentioned mounting means and said tag wheel mounting means; means for pivotally associating the adjacent ends of the leaf springs for said drive wheels and said tag wheels with said spring seat means at positions spaced longitudinally of said truck from the pivotal mounting of said spring seat means on said chassis; means for pivoting said spring seat means in one direction to lower said drive wheel spring association and simultaneously raise said tag wheel spring association; and said spring seat means being constructed and arranged so that with said tag wheels in a lowered position, said drive wheel spring association is at a higher elevation than said tag wheel spring association.

Claim 3

In a tag wheel lift, as defined in claim 1, including: a seat for the opposite end of each said tag wheel spring, permitting sliding movement of said opposite end.

Claim 4

In a tag wheel lift, as defined in claim 1, wherein: said tag wheels are mounted rearwardly of said drive wheels; said pivotal mounting of said spring seat means on said chassis including a pivot shaft; said spring seat means each comprises a pair of side plates attached to an end of said pivot shaft extending laterally beyond a longitudinal beam of said chassis, a pin and a roller for engaging the rear end of a drive wheel leaf spring mounted at the upper corner of said plates and extending therebetween, a pivot pin for the front end of said tag wheel leaf spring extending between the lower rear corners of said side plates, and transverse reinforcing means extending between said side plates adjacent the upper rear and lower front corners thereof; and rear seat means for the rear end of each said tag wheel spring, including a box-shaped member attached to said chassis having a forwardly extending guide for the underside of said tag wheel spring and a roller for engaging the top of said tag wheel spring.

Claim 5

In a tag wheel lift, as defined in claim 3, wherein: each said tag wheel leaf spring comprises a plurality of superimposed leaves, with the upper leaf being connected at the front end to said pivot pin and the rear end thereof extending beneath said roller of said rear seat, intermediate leaves of successively shorter length, the lowermost leaf extending forwardly to a position adjacent said spring seat and rearwardly to within said rear seat, and clamps connecting said upper and lower leaves at positions between said mounting means and said ends.

Claim 6

In a tag wheel lift for a truck or the like having a chassis, drive wheels at each side of said chassis, mounting means including an axle for driving said drive wheels, leaf springs attached to said mounting means for supporting said chassis from said drive wheels, tag wheels at each side of said chassis and spaced longitudinally from said drive wheels, means for mounting said tag wheels for rotation and leaf springs attached to said tag wheel mounting means for supporting said chassis from said tag wheels when in use, the improvement including: spring seat means at each side and disposed between said first mentioned mounting means and said tag wheel mounting means; a shaft mounted transversely of said chassis for pivotal movement and attached to said spring seat means; means for pivotally associating the adjacent ends of the leaf springs for said drive wheels and said tag wheels with said spring seat means at positions spaced longitudinally of said truck from said shaft; means for turning said shaft so as to cause said spring seat means to pivot in one direction to lower said drive wheel spring association and simultaneously raise said tag wheel spring association; and said spriNg seat means being constructed and arranged so that with said tag wheels in a lowered position, said drive wheel spring association is at a higher elevation than said tag wheel spring association.

Claim 7

In a tag wheel lift for a truck or the like having a chassis, drive wheels at each side of said chassis, mounting means including an axle for driving said drive wheels, leaf springs attached to said mounting means for supporting said chassis from said drive wheels, tag wheels at each side of said chassis and spaced longitudinally from said drive wheels, means for mounting said tag wheels for rotation and leaf springs attached to said tag wheel mounting means for supporting said chassis from said tag wheels when in use, the improvement including: spring seat means at each side and disposed between said first mentioned mounting means and said tag wheel mounting means; a shaft mounted transversely of said chassis for pivotal movement and attached to said spring seat means; means for pivotally associating the adjacent ends of the leaf springs for said drive wheels and said tag wheels with said spring seat means at positions spaced longitudinally of said truck from said shaft; means for turning said shaft so as to cause said spring seat means to pivot in one direction to lower said drive wheel spring association and simultaneously raise said tag wheel spring association; and said spriNg seat means being constructed and arranged so that with said tag wheels in a lowered position, said drive wheel spring association is at a higher elevation than said tag wheel spring association.

Claim 8

In a tag wheel lift, as defined in claim 5, wherein: said means for turning said shaft includes a hydraulic cylinder and piston.

Claim 9

In a tag wheel lift, as defined in claim 6, including: means pivotally connecting said piston rod means to rocker arm means attached to said shaft.

Claim 10

In a tag wheel lift, as defined in claim 7, wherein: said hydraulic cylinder is single acting.

Claim 11

In a tag wheel lift, as defined in claim 7, wherein: said hydraulic cylinder is double acting.

Claim 12

In a tag wheel lift, as defined in claim 9, wherein: said means pivotally connecting said piston rod means and said rocker arm means includes a lost motion connection.

Claim 13

In a tag wheel lift, as defined in claim 7, wherein: said hydraulic cylinder is double acting; and said piston rod means is interconnected to said rocker arm means through a link pivotally connected at its upper end to said piston rod means and at its lower end pivotally connected to said rocker arm means, said link providing a lost motion connection between said piston rod means and rocker arm means, permitting said piston rod means to move rearwardly from the upper end of said rocker arm means without turning said shaft, but causing said link to engage said rocker arm means to turn said shaft when said piston rod means moves forwardly.