US 7,621,356 B2Granted

Pallet puller tool

OwnerCraig D. Quarberginventor

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Abstract

A powered, directionally steerable trailer jack that can be used to elevate and lower a trailer tongue and having a caster wheel assembly affixed to a lower end of the jack. The caster wheel assembly includes a shroud having the wheels' axle journaled for rotation at a lower end thereof along with a pair of shafts also journaled for rotation in the shroud and oriented parallel to the axle. A chain and sprocket arrangement provides a low-speed, high torque transmission between one of the shafts and the axle and a high-speed, low torque transmission between the other of the shafts and the axle. The trailer jack assembly can be tilted out of its vertical disposition to provide adequate clearance when the trailer is being pulled over uneven road surfaces. The power for driving the wheels may be provided manually by means of a crank for turning one or the other of the shafts or by an electric motor coupled one of the shafts.

Claims19

Dependent claims

A trailer jack comprising:

(a) a mounting bracket adapted to be secured to a tongue of a trailer, the mounting bracket includes a U-shaped flange plate adapted to be clamped to the trailer tongue, the flange plate having a cylindrical stub attached to a planar surface thereof, the cylindrical stub including a plurality of bores extending diametrically therethrough, a tubular sleeve affixed to the tubular housing of the jack screw and adapted to receive the cylindrical stub therein, the tubular sleeve having a diametric bore formed therethrough and alignable with a selected one of the plurality of bores in the cylindrical stub, and a pin adapted to be inserted in aligned bores in the sleeve and stub;
(b) a jack screw having an outer tubular housing and an inner tubular member concentrically disposed in the tubular housing with means for longitudinally displacing the tubular housing relative to the inner tubular member and with the mounting bracket affixed to the outer tubular housing;
(c) a shroud secured to the lower end of the inner tubular member, the shroud having an axle journaled in bearings at a lower end of the shroud, the axle supporting a pair of wheels in side-by-side relation along with a first sprocket of a relatively large diameter affixed to the axle;
(d) at least one shaft supporting a second sprocket of a relatively small diameter compared to the diameter of the first sprocket and said at least one shaft being journaled for rotation in the shroud, the one shaft being parallel to said axle;
(e) an endless chain deployed about the first sprocket and the second sprocket;
and
(f) means for applying a torque to the one shaft.

4 more elements

A trailer jack comprising:

(a) a mounting bracket adapted to be secured to a tongue of a trailer, the mounting bracket includes a U-shaped flange plate adapted to be clamped to the trailer tongue, the flange plate having a cylindrical stub attached to a planar surface thereof, the cylindrical stub including a plurality of bores extending diametrically therethrough, an annular V-groove formed in the cylindrical stub proximate a free end thereof;
the sleeve includes at least one threaded bore formed through a peripheral wall thereof at a location that is aligned with the V-groove when the stub is inserted into the sleeve;
and at least one set screw screwed into the threaded bore for releasably holding the sub within the tubular sleeve, a tubular sleeve affixed to the tubular housing of the jack screw and adapted to receive the cylindrical stub therein, the tubular sleeve having a diametric bore formed therethrough and alignable with a selected one of the plurality of bores in the cylindrical stub, and a pin adapted to be inserted in aligned bores in the sleeve and stub;
(b) a jack screw having an outer tubular housing and an inner tubular member concentrically disposed in the tubular housing with means for longitudinally displacing the tubular housing relative to the inner tubular member and with the mounting bracket affixed to the outer tubular housing;
(c) a shroud secured to the lower end of the inner tubular member, the shroud having an axle journaled in bearings at a lower end of the shroud, the axle supporting a pair of wheels in side-by-side relation along with a first sprocket of a relatively large diameter affixed to the axle;
(d) at least one shaft supporting a second sprocket of a relatively small diameter compared to the diameter of the first sprocket and said at least one shaft being journaled for rotation in the shroud, the one shaft being parallel to said axle;
(e) an endless chain deployed about the first sprocket and the second sprocket;
and
(f) means for applying a torque to the one shaft.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/601,201Filed 17 Nov 2006
Published: US 2008/0116434 A122 May 2008
Granted: 24 Nov 2009
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

B60S 9/215
Comprising a rotatably driven auxiliary wheel or endless track, e.g. driven by ground wheel: driven by an auxiliary motor
B60D 1/246
Characterised by arrangements for particular functions: for actuating the hitch by powered means
B60D 1/66
Auxiliary devices: props
B60S
Servicing, cleaning, repairing, supporting, lifting, or manoeuvring of vehicles, not otherwise provided