Independent hydraulic header lift and flotation system
A hydraulic lift/flotation system for the header of a crop harvesting machine wherein each side of the header is supported by a single cylinder, which performs both the flotation and lift functions. For even lifting and flotation of an unbalanced header, each cylinder has its own control valve, pump, and accumulator. The operator sets the desired flotation force by actuating rocker switches; one switch position allows hydraulic oil to enter an accumulator to reduce header contact force with the ground. The other position allows oil to exit the accumulator to increase header contact force with the ground. To evenly float an unbalanced header, separate switches adjust each side independently. Once the flotation forces are set, the control valves will return to this preset flotation condition whenever float mode is selected, regardless of subsequent header lift and lower operations.
1. In a harvesting machine having a frame adapted for movement over the ground, the frame having a front end, an opposing rear end, and an operator's platform, an elongate crop harvesting header having a first end and a second opposing end, the first and second ends defining the length of the elongate header, the header supported at first and second support points, intermediate the first and second ends, by the frame across the front end of the frame for generally vertical movement relative to the ground, the improvement comprising:
a header lift and flotation system interconnecting the header and the frame for selectively raising and lowering the header relative to the ground and setting flotation parameters, the header lift and flotation system including:
left and right hand hydraulic cylinders interconnecting the frame and the header adjacent the respective first and second support points;
a hydraulic fluid reservoir;
substantially independent left and right hand electro-hydraulic circuits, each circuit including an independent hydraulic pump and at least one valve operated by electrical signals, interconnecting the hydraulic fluid reservoir and the respective left and right hand hydraulic cylinders;
left and right hand manually manipulated switches:
an electronic programmable controller interconnecting the switches and the valves such that independent manipulation of the switches causes the controller to emit electrical signals to the valves to establish independent flotation and lift settings.
2. The improvement of claim 1 , wherein:
each left and right electro-hydraulic circuit further includes hydraulic accumulator.
3. The improvement of claim 2 , wherein:
the switches are located on the operator's platform.
4. The improvement of claim 3 , wherein:
the switches are rocker switches.
5. The improvement of claim 4 , wherein:
each of the left and right hand switches has a first position that signals the controller to allow hydraulic oil to enter the respective accumulator to reduce header contact force with the ground.
6. The improvement of claim 5 , wherein:
each of the left and right band switches has a second position that signals the controller to allow hydraulic oil to exit the respective accumulator to increase header contact force with the ground.
7. The improvement of claim 6 , wherein the left and right hand switches operate independently of each other.
8. In a harvesting machine having a frame adapted for movement over the ground, the frame having a front end, an opposing rear end, and an operator's platform, an elongate crop harvesting header having a first end and a second opposing end, the first and second ends defining the length of the elongate header, the header supported at first and second support points, intermediate the first and second ends, by the frame across the front end of the frame for generally vertical movement relative to the ground, the improvement comprising:
a header lift and flotation system interconnecting the header and the frame for selectively raising and lowering the header relative to the ground and setting flotation parameters, the header lift and flotation system including:
left and right hand hydraulic cylinders interconnecting the frame and the header adjacent the respective first and second support points;
a hydraulic fluid reservoir;
substantially independent left and right hand electro-hydraulic circuits, each circuit including an independent hydraulic pump and at least one valve operated by electrical signals, interconnecting the hydraulic fluid reservoir and the respective left and right hand hydraulic cylinders;
left and right hand manually manipulated switches;
an electronic programmable controller interconnecting the switches and the valves such that independent manipulation of the switches causes the controller to emit electrical signals to the valves to establish independent flotation and lift settings for the left and right hand hydraulic cylinders.
9. The improvement of claim 8 , wherein:
each left and right electro-hydraulic circuit further includes hydraulic accumulator.
10. The improvement of claim 9 , wherein:
the switches are located on the operator's platform and are rocker-type switches.
11. The improvement of claim 10 , wherein:
each of the left and right hand switches has a first position that signals the controller to allow hydraulic oil to enter the respective accumulator to reduce header contact force with the ground, and
each of the left and right hand switches has a second position that signals the controller to allow hydraulic oil to exit the respective accumulator to increase header contact force with the ground.
12. The improvement of claim 11 wherein:
the left and right hand switches operate independently of each other.
13. A crop harvesting machine comprising:
a self-propelled frame adapted for movement over the ground, the frame having a front end, an opposing rear end;
an operator's platform affixed to and supported by the frame;
an elongate crop harvesting header having a first end and a second opposing end, the first and second ends defining the length of the elongate header, the header supported at first and second support points, intermediate the first and second ends, by the frame across the front end of the frame for generally vertical movement relative to the ground;
a header lift and flotation system interconnecting the header and the frame for selectively raising and lowering the header relative to the ground and setting flotation parameters, the header lift and flotation system including:
left and right hand hydraulic cylinders interconnecting the frame and the header adjacent the respective first and second support points;
a hydraulic fluid reservoir;
substantially independent left and right hand electro-hydraulic circuits, each circuit including an independent hydraulic pump and at least one valve operated by electrical signals, interconnecting the hydraulic fluid reservoir and the respective left and right hand hydraulic cylinders;
left and right hand manually manipulated switches; and
an electronic programmable controller interconnecting the switches and the valves such that independent manipulation of the switches causes the controller to emit electrical signals to the valves to establish independent flotation and lift settings for the left and right hand hydraulic cylinders.
14. The crop harvesting machine of claim 13 , wherein:
each left and right electro-hydraulic circuit further includes hydraulic accumulator.
15. The improvement of claim 14 , wherein:
the switches are located on the operator's platform.
16. The improvement of claim 13 , wherein:
the switches are rocker switches;
each of the left and right band switches has a first position that signals the controller to allow hydraulic oil to enter the respective accumulator to reduce header contact force with the ground; and
each of the left and right hand switches has a second position that signals the controller to allow hydraulic oil to exit the respective accumulator to increase header contact force with the ground.
17. The improvement of claim 16 , wherein
the left and right hand switches operate independently of each other.