Dynamic seat-moving and leveling device

A tractor having a center of gravity, said tractor being adapted to carry an operator along a path having a varying direction and across a terrain having a varying incline, said tractor comprising:

• a tractor frame;
• a right wheel rotatably mounted to said tractor frame about a right rotational point;
• a left wheel rotatably mounted to said tractor frame about a left rotational point;
• an axle centerline defined by said right rotational point and said left rotational point;
• a seat frame movably coupled to said tractor frame and adapted to support said operator, said seat frame being repositionable relative to said tractor frame to a right position, a left position, and a central position;
• an inclinometer providing a reaction to an angular inclination of said inclinometer, wherein said angular inclination is affected by said tractor being subjected to said varying direction of said path and said varying incline between said right wheel and said left wheel, said inclinometer being coupled to said seat frame;
• a deadband existing between a first predetermined limit and a second predetermined limit of said angular inclination;
• and
• a seat drive coupled to said tractor frame and said seat frame, said seat drive, in response to said reaction, driving said seat frame to said tractor frame to said right position upon said angular inclination shifting beyond said first predetermined limit toward said left wheel, driving said seat frame to said left position upon said angular inclination shifting beyond said second predetermined limit toward said right wheel, and holding said seat frame substantially fixed relative to said tractor frame when said angular inclination is within said deadband wherein said angular inclination of said inclinometer is substantially level, said seat frame at said right position and said left position defining a virtual rotational point about which said seat frame effectively rotates, said virtual rotational point being located below said center of gravity.

A tractor having a center of gravity, said tractor being adapted to carry an operator along a path having a varying direction and across a terrain having a varying incline, said tractor comprising:

• a tractor frame;
• a right wheel rotatably mounted to said tractor frame about a right rotational point, said right wheel contacting said terrain at a right contact point;
• a left wheel rotatably mounted to said tractor frame about a left rotational point, said left wheel contacting said terrain at a left contact point;
• a contact line defined by said right contact point and said left contact point;
• an axle centerline defined by said right rotational point and said left rotational point;
• an arcuate track attached to said frame and having a center of curvature below said center of gravity;
• a seat frame adapted to support said operator and movably coupled to said tractor frame by way of said arcuate track along which said seat frame travels about said center of curvature, said seat frame being repositionable relative to said tractor frame to a right position, a left position and a central position, said seat frame having a bottom point defined as a lowest point of said seat frame when said seat frame is at said central position and said contact line is horizontal;
• an inclinometer coupled to said seat frame, said inclinometer providing a reaction to an angular inclination of said inclinometer, wherein said angular inclination is affected by said tractor being subjected to said varying direction of said path and said varying incline between said right wheel and said left wheel;
• a plumb element associated with said inclinometer, said plumb element having a position that shifts toward said right wheel and toward said left wheel in response to changes in said angular inclination to create said reaction of said inclinometer;
• a magnetic centering force urging said plumb element to a neutral position, wherein said plumb element remains substantially at said neutral position until said angular inclination exceeds at least one of said first predetermined limit and said second predetermined limit, thereby creating a deadband therebetween;
• and
• a seat drive coupled to said tractor frame and said seat frame, said seat drive, in response to said reaction, driving said seat frame relative to said tractor frame to said right position upon said angular inclination shifting beyond said first predetermined limit toward said left wheel, driving said seat frame relative to said tractor frame to said left position upon said angular inclination shifting beyond said second predetermined limit toward said right wheel, and holding said seat frame substantially fixed relative to said tractor frame when said angular inclination is substantially within said deadband within which said angular inclination is substantially level.