Lifting mechanism for front end loader

Claim 5

An apparatus as claimed in claim 1, further comprising a pair of second hydraulic jacks, each supported by said tractor frame and having an extendible rod upwardly movable against said boom.

Claim 6

Apparatus as claimed in claim 2, further comprising a pair of brackets, each rigidly attached to said tractor frame at a point forward of the tractor center of gravity and supporting said pivotal mounting of said second link to the tractor frame.

Claim 7

Apparatus as claimed in claim 3, further comprising a pair of rear axle housings, each rigidly attached to said tractor rear axle at a distance interior said tractor wheel, said housings having pivotal mounting connections for attaching said pivotal boom end and said first hydraulic jack.

Claim 8

Apparatus as claimed in claim 4 wherein said first and second links extend rearwardly from their respective pivotal mountings to the boom and fraMe to approximately the center of gravity of said tractor.

Claim 9

Apparatus as claimed in claim 5, further comprising a pair of third hydraulic jacks pivotally mounted on said rear axle housing, and having an extendible rod forwardly actuable along said boom.

Claim 10

Apparatus as claimed in claim 6, further comprising a linking element pivotally attached to said boom and having a pivotal connection along its length for attachment to said third hydraulic jack extendible rod.

Claim 11

Lifting apparatus for attachement to a tractor frame and rear axle, comprising: a pair of rear axle housings, each having means for rigidly attaching to the tractor rear axle at a point interior to a rear wheel, and having at least two pivotal mounting connections; a pair of booms, each mounted at one of its ends to said housing pivotal mounting connections and extending therefrom to a position forward the tractor frame, and having a forward end adaptable for connection to a tool; a pair of first frame brackets, each rigidly attached to the tractor frame in alignment with a boom at a point forward the center of gravity of said tractor, and having a pivotal mounting connection; a pair of upwardly extending boom guide frames rigidly attached to respective sides of said tractor and slidably engaging the respective booms to stabilize lateral motion of the latter; a pair of L-shaped first links each pivotally connected at one end to a respective boom at a point substantially adjacent said first frame bracket pivotal mounting connection and having a rearwardly extending link end; a pair of second links each pivotally connected at one end to a respective first frame bracket pivot mounting point and extending rearwardly in crossing relation to the first link for pivotal connection to the rearwardly extending link end of the first link; and pair of hydraulically actuated cylinders, each of said cylinders pivotally mounted to said rear axle housing pivotal mounting connections, and having an extendible rod pivotally connected to the vertex of one of the L-links at a distance below the pivotal connection between the first and second links.

Claim 12

Lifting apparatus for attachement to a tractor frame and rear axle, comprising: a pair of rear axle housings, each having means for rigidly attaching to the tractor rear axle at a point interior to a rear wheel, and having at least two pivotal mounting connections; a pair of booms, each mounted at one of its ends to said housing pivotal mounting connections and extending therefrom to a position forward the tractor frame, and having a forward end adaptable for connection to a tool; a pair of first frame brackets, each rigidly attached to the tractor frame in alignment with a boom at a point forward the center of gravity of said tractor, and having a pivotal mounting connection; a pair of upwardly extending boom guide frames rigidly attached to respective sides of said tractor and slidably engaging the respective booms to stabilize lateral motion of the latter; a pair of L-shaped first links each pivotally connected at one end to a respective boom at a point substantially adjacent said first frame bracket pivotal mounting connection and having a rearwardly extending link end; a pair of second links each pivotally connected at one end to a respective first frame bracket pivot mounting point and extending rearwardly in crossing relation to the first link for pivotal connection to the rearwardly extending link end of the first link; and pair of hydraulically actuated cylinders, each of said cylinders pivotally mounted to said rear axle housing pivotal mounting connections, and having an extendible rod pivotally connected to the vertex of one of the L-links at a distance below the pivotal connection between the first and second links.

Claim 13

Lifting apparatus for attachement to a tractor frame and rear axle, comprising: a pair of rear axle housings, each having means for rigidly attaching to the tractor rear axle at a point interior to a rear wheel, and having at least two pivotal mounting connections; a pair of booms, each mounted at one of its ends to said housing pivotal mounting connections and extending therefrom to a position forward the tractor frame, and having a forward end adaptable for connection to a tool; a pair of first frame brackets, each rigidly attached to the tractor frame in alignment with a boom at a point forward the center of gravity of said tractor, and having a pivotal mounting connection; a pair of upwardly extending boom guide frames rigidly attached to respective sides of said tractor and slidably engaging the respective booms to stabilize lateral motion of the latter; a pair of L-shaped first links each pivotally connected at one end to a respective boom at a point substantially adjacent said first frame bracket pivotal mounting connection and having a rearwardly extending link end; a pair of second links each pivotally connected at one end to a respective first frame bracket pivot mounting point and extending rearwardly in crossing relation to the first link for pivotal connection to the rearwardly extending link end of the first link; and pair of hydraulically actuated cylinders, each of said cylinders pivotally mounted to said rear axle housing pivotal mounting connections, and having an extendible rod pivotally connected to the vertex of one of the L-links at a distance below the pivotal connection between the first and second links.

Claim 14

Lifting apparatus for attachement to a tractor frame and rear axle, comprising: a pair of rear axle housings, each having means for rigidly attaching to the tractor rear axle at a point interior to a rear wheel, and having at least two pivotal mounting connections; a pair of booms, each mounted at one of its ends to said housing pivotal mounting connections and extending therefrom to a position forward the tractor frame, and having a forward end adaptable for connection to a tool; a pair of first frame brackets, each rigidly attached to the tractor frame in alignment with a boom at a point forward the center of gravity of said tractor, and having a pivotal mounting connection; a pair of upwardly extending boom guide frames rigidly attached to respective sides of said tractor and slidably engaging the respective booms to stabilize lateral motion of the latter; a pair of L-shaped first links each pivotally connected at one end to a respective boom at a point substantially adjacent said first frame bracket pivotal mounting connection and having a rearwardly extending link end; a pair of second links each pivotally connected at one end to a respective first frame bracket pivot mounting point and extending rearwardly in crossing relation to the first link for pivotal connection to the rearwardly extending link end of the first link; and pair of hydraulically actuated cylinders, each of said cylinders pivotally mounted to said rear axle housing pivotal mounting connections, and having an extendible rod pivotally connected to the vertex of one of the L-links at a distance below the pivotal connection between the first and second links.

Claim 15

Apparatus as claimed in claim 8, further comprising a second pair of hydraulic jacks, each mounted on said first frame bracket and having an extendible rod upwardly moveable against said boom.

Claim 16

Apparatus as claimed in claim 9, further comprising a third pair of hydraulic jacks, each jack pivotally connected at one of its ends to said rear axle housing and having an extendible rod with a pivotal mounting connection; and a further link pivotally connected to said boom and to said extendible rod pivotal mounting connection.

Claim 17

The apparatus of claim 1 including an inverted U-shaped guide frame mounted to the tractor and including upwardly extending, rigid guides, and rollers attached to inner surfaces of the respective booms and oriented to contact and roll along outer surfaces of the respective guides to stabilize lateral motion of the booms as the latter are raised and lowered.

Claim 18

A lifting apparatus for attachment to a tractor and comprising: a. a pair of elongated booms pivotally mounted on respective sides of the tractor at points near the tractor rear axle and extending forwardly to the tractor front end and movable between a substantially horizontal rest position and an elevated position, and including a bucket or the like pivotally attached to front ends of the booms forwardly of the tractor front end; b. a pair of first links each pivotally mounted at one end to a respective boom, and a pair of second links each pivotally mounted at one end to the tractor frame forward of the tractor center of gravity and at the other end to the other end of the first link, the links being crossed when the booms are in the rest position; c. a first pair of hydraulic jacks each pivotally mounted to the tractor frame at a point near the tractor rear axle and having an extendible rod pivotally connecteD to the other end of a respective first link at a point lower than the pivotal connection between the first and second links when the booms are in the rest position; and d. a second pair of hydraulic jacks each connected to the tractor at one end near the rear axle and having a generally forwardly extendible rod, and a pair of third links each connected pivotally at one end to a respective boom and each connected pivotally along its length to an extendible rod of the third pair of hydraulic jacks, and a connector connecting the third link at a point along its length to the bucket or the like whereby acuation of the last-mentioned hydraulic jacks tilts the bucket or the like with respect to the booms.

Claim 19

A lifting apparatus for attachment to a tractor and comprising: a. a pair of elongated booms pivotally mounted on respective sides of the tractor at points near the tractor rear axle and extending forwardly to the tractor front end and movable between a substantially horizontal rest position and an elevated position, and including a bucket or the like pivotally attached to front ends of the booms forwardly of the tractor front end; b. a pair of first links each pivotally mounted at one end to a respective boom, and a pair of second links each pivotally mounted at one end to the tractor frame forward of the tractor center of gravity and at the other end to the other end of the first link, the links being crossed when the booms are in the rest position; c. a first pair of hydraulic jacks each pivotally mounted to the tractor frame at a point near the tractor rear axle and having an extendible rod pivotally connecteD to the other end of a respective first link at a point lower than the pivotal connection between the first and second links when the booms are in the rest position; and d. a second pair of hydraulic jacks each connected to the tractor at one end near the rear axle and having a generally forwardly extendible rod, and a pair of third links each connected pivotally at one end to a respective boom and each connected pivotally along its length to an extendible rod of the third pair of hydraulic jacks, and a connector connecting the third link at a point along its length to the bucket or the like whereby acuation of the last-mentioned hydraulic jacks tilts the bucket or the like with respect to the booms.