Speed and direction control mechanism for a tractor having two separately driven front wheels

Claim 2

A mechanism for controlling the outputs of two hydraulic pumps separately driving the front wheels of a tractor through two hydraulic motors respectively connected to said pumps comprising arms pivotally mounted on a respectively connected to said pumps comprising arms pivotally mounted on a respective pump to vary the outputs of said pumps, an operating lever, means pivotally mounting said lever to move forwardly and rearwardly in a vertical longitudinal plane and to rotate about a generally vertical axis in said longitudinal plane, means for mounting said pumps with said arms at substantially the same level and movable in the same direction on opposite sides of the longitudinal plane to similarly vary the outputs of said pumps, links pivotally connected to said respective arms and to said operating lever to rotate said arms as said operating lever is pivoted, means for holding said lever in any given position in the longitudinal plane while permitting overriding by a tractor operator, and release means connected to said holding means to disengage said holding means for free movement of said operating lever.

Claim 3

A mechanism for controlling the outputs of two hydraulic pumps separately driving through hydraulic motors the two front wheels of a tractor having a frame with two intermediate longitudinally extending frame members and comprising a mounting member between and secured to said frame members and having two outer first portions and two inner second portions spaced transversely from said outer portions, two hydraulic pumps mounted on said first outer respective portions of said mounting member and having drive shafts extending towards one another in axial alignment, means supported by said inner second respective portions of said mounting member and in axial alignment with and coupled to said shafts for driving said pumps, pintle arms on said hydraulic pumps for controlling the output thereof and pivotable in a horizontal plane, an operating lever, means for mounting said lever to pivot therewith in a vertical longitudinal plane, two links on opposite sides of the longitudinal plane pivotally connected to said operating lever and to respective pintle arms to vary the outputs of said hydraulic pumps by movement of said operating lever in the longitudinal plane.

Claim 4

A mechanism for controlling the outputs of two hydraulic pumps separately driving through hydraulic motors the two front wheels of a tractor having a frame with two intermediate longitudinally extending frame members and comprising a mounting member between and secured to said frame members and having two outer first portions and two inner second portions spaced transversely from said outer portions, two hydraulic pumps mounted on said first outer respective portions of said mounting member and having drive shafts extending towards one another in axial alignment, means supported by said inner second respective portions of said mounting member and in axial alignment with and coupled to said shafts for driving said pumps, pintle arms on said hydraulic pumps for controlling the output thereof and pivotable in a horizontal plane, an operating lever, means for mounting said lever to pivot therewith in a vertical longitudinal plane, two links on opposite sides of the longitudinal plane pivotally connected to said operating lever and to respective pintle arms to vary the outputs of said hydraulic pumps by movement of said operating lever in the longitudinal plane.

Claim 5

A mechanism as set forth in claim 2 where said operating lever has means between said pivot means and said links to rotatably mount said lever on said pivot means about an axis in the longitudinal plane to create a differential between the outputs of said pumps by rotation of said lever about the lever axis.

Claim 6

A mechanism as set forth in claim 2 wherein friction means and release means are provided and said friction means mounted on said frame and connected to said means for pivotally mounting said lever to oppose longitudinal movement of said lever and holding said lever in a given position and said release means being mounted on said frame and connected to said friction means for permitting said lever to freely move through the range of forward and rearward positions.

Claim 7

A mechanism as set forth in claim 4 wherein said friction means comprises a brakedrum mounted on said pivot means, a brake band partially extending circumferentially around said drum and pivotally mounted lever means attached to said brake band to tighten said brake band in one position and release said brake band in the other position for free movement of said lever.

Claim 8

A mechanism as set forth in claim 5 wherein said brake band has ends and said lever means is pivotally mounted adjacent thereto and has means connecting said ends of said brake band to tighten said brake band on rotation of said lever in one direction and loosen said brake band on rotation in the opposite direction.

Claim 9

A mechanism as set forth in claim 6 wherein said lever means is spring loaded to hold said lever and brake band in the holding positIon.

Claim 10

A mechanism as set forth in claim 7 wherein release means are provided and connected to said lever to hold said lever and brake means in a disengaged condition.

Claim 11

A mechanism as set forth in claim 8 wherein said release means includes a brake lever pivotally mounted at one end, a link connected to said lever means and said brake lever to loosen said friction means on rotation of said brake lever and releasable lock means engaging said brake lever to hold said brake lever and said friction means in a disengaged condition.

Claim 12

A speed and direction control mechanism for a tractor having two separately driven front wheels comprising two sets of hydraulic pumps and motors with said motors driving respective wheels and said pumps connected to respective motors for controlling the output of the respective motors, said pumps having pintle arms, movable in the same direction on opposite sides of a longitudinal plane and aligned at substantially the same level and rotatably mounted on said tractor, a rotatably mounted pivot shaft extending transversely, an operating lever mounted on said pivot shaft for pivoting with said shaft in the longitudinal plane and rotating about an axis in the longitudinal plane, a bracket mounted on said lever to pivot and rotate with said lever, two ball pivots on said bracket on opposite sides of the longitudinal plane, ball pivots on said respective pintle arms, two links on opposite sides of the longitudinal plane and pivotally connected to respective bracket ball of pivots and a respective pintle arm ball pivot to move a respective pintle arm on pivoting and rotating said lever to vary the outputs of said pumps, a brake drum coupled to said pivot shaft, a brake band mounted on said drum, lever means pivotally mounted on said tractor and having attaching means connected to said ends of said brake band for tightening and loosening said brake band on said drum, a spring connected to said lever means to grip said brake band on said drum to retain said lever in any pivoted position and release means connected to said lever means to move said lever means to relieve said brake band from a gripping relation to permit free pivoting of said operating lever.

Claim 13

A speed and direction control mechanism for a tractor having two separately driven front wheels comprising two sets of hydraulic pumps and motors with said motors driving respective wheels and said pumps connected to respective motors for controlling the output of the respective motors, said pumps having pintle arms, movable in the same direction on opposite sides of a longitudinal plane and aligned at substantially the same level and rotatably mounted on said tractor, a rotatably mounted pivot shaft extending transversely, an operating lever mounted on said pivot shaft for pivoting with said shaft in the longitudinal plane and rotating about an axis in the longitudinal plane, a bracket mounted on said lever to pivot and rotate with said lever, two ball pivots on said bracket on opposite sides of the longitudinal plane, ball pivots on said respective pintle arms, two links on opposite sides of the longitudinal plane and pivotally connected to respective bracket ball of pivots and a respective pintle arm ball pivot to move a respective pintle arm on pivoting and rotating said lever to vary the outputs of said pumps, a brake drum coupled to said pivot shaft, a brake band mounted on said drum, lever means pivotally mounted on said tractor and having attaching means connected to said ends of said brake band for tightening and loosening said brake band on said drum, a spring connected to said lever means to grip said brake band on said drum to retain said lever in any pivoted position and release means connected to said lever means to move said lever means to relieve said brake band from a gripping relation to permit free pivoting of said operating lever.

Claim 14

A speed and direction control mechanism as set forth in claim 10 wherein said release means comprises a foot pedal and a link connected between said foot pedal and said lever means.

Claim 15

A speed and direction control mechanism as set forth in claim 10 wherein said ball pivots on said bracket rotate in the same arc around the lever axis.