Crop machine with an electronically controlled hydraulic cylinder flotation system

Patent metadata

Field	Value
Publication number	US-10624263-B2
Application number	US-201715837670-A
Country	US
Kind code	B2
Filing date	Dec 11, 2017
Priority date	Jun 21, 2016
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A header is supported by a pair of hydraulic float cylinders, where a float pressure to the cylinders is directly controlled by an electronic control supplying a variable control signal to a PPRR valve arrangement to maintain the float pressure at a predetermined value. At the set pressure a predetermined lifting force is provided to the header. A position sensor is used to generate an indication of movement and/or acceleration and/or velocity. The electronic control is arranged, in response to changes in the sensor signal, to temporarily change the control signal to vary the lifting force and thus change the dynamic response of the hydraulic float cylinder. A lift force greater than that required to lift the header can be provided by a lift cylinder and can be opposed in a controlled manner to apply a controlled downforce by the back of the same cylinder or by a separate component.

First claim

The invention claimed is:

1. A crop machine comprising:
a support vehicle for running over ground;
a crop header including a crop engaging system and at least one ground engaging component for providing a supporting force from the ground as the vehicle runs over the ground so as to cause ground contact;
a support apparatus for supporting the crop header relative to the vehicle for upward and downward floating movement of the crop header so that a proportion of a supporting force to counterbalance the weight of the crop header is supplied by a lifting force from the support apparatus and a remaining portion is supplied by the ground engaging component caused by ground pressure on the ground;
the support apparatus comprising:
at least one hydraulic float cylinder having a piston movable in the cylinder arranged such that movement of the piston relative to the cylinder causes said lifting force from the support apparatus to be applied to the crop header;
a hydraulic lift system containing a hydraulic fluid under a hydraulic pressure which is set and including a fluid communication applying a force to a side of the piston in said cylinder in a direction to lift the crop header;
the hydraulic lift system in operation being arranged to provide a pressure on the piston defining a first lifting force;
a supplementary pressure system comprising a chamber and a fluid supply supplying fluid under pressure to the chamber so that the chamber applies a supplementary force to the crop header so that a combination of the first lifting force and the supplementary force provides said lifting force from the support apparatus and acts to support the header while applying said ground pressure on the ground;
and an electronic control system for controlling the lifting force from the support apparatus in response to at least one input which determines a required lifting force;
wherein the electronic control system is arranged to supply to the supplementary pressure system a control signal so as to vary the supplementary force and thereby change the lifting force from the support apparatus;
and wherein the hydraulic lift system is arranged such that the hydraulic pressure thereof is not controlled by said electronic control system when the lifting force from the support apparatus is changed.

2. The crop machine according to claim 1 wherein the hydraulic lift system is arranged such that the first lifting force is greater than the required lifting force and the supplementary force is applied in a downward direction.

3. The crop machine according to claim 1 wherein there is provided a movement sensor arranged to provide a sensor signal to said electronic control system and to instantaneously change the sensor signal in response to movement of the header in said upward and downward floating movement of the header caused by a change in said ground contact as the vehicle runs over the ground and a valve arrangement operable to provide precise, instantaneous control of the pressure of said supplementary pressure system to maintain the pressure of the hydraulic fluid in the supplementary pressure system at a value directly dependent on the control signal applied to the valve arrangement, said electronic control system being arranged instantaneously in response to said change in said sensor signal to temporarily change the control signal responsive to said change in said ground contact as the vehicle runs over the ground.

4. The crop machine according to claim 3 wherein said electronic control system is arranged subsequently in response to said sensor signal to revert to a set value of the pressure of the supplementary pressure system.

5. The crop machine according to claim 3 wherein said electronic control system is arranged in response to changes in said sensor signal to temporarily change the control signal to vary the supplementary force of the supplementary pressure system in response to detected movement of the crop header.

6. The crop machine according to claim 1 wherein the supplementary pressure system is arranged to vary pressure in a down pressure hydraulic system where hydraulic fluid from the down pressure hydraulic system is applied to the cylinder on a reverse face of the piston so as to oppose the pressure from said hydraulic system.

7. The crop machine according to claim 6 wherein movement of the piston in the cylinder, caused by the movement of the header, effects changes in the first lifting force and wherein the electronic control system is arranged to modify the control signal in response to said changes in the first lifting force caused by said movement of the piston.

8. The crop machine according to claim 1 wherein the supplementary pressure system includes a valve arrangement which has the characteristic that the valve arrangement acts to maintain the pressure of the hydraulic fluid in the chamber at a constant value, which value is dependent on the control signal applied to the valve arrangement, during changes in volume of the cylinder caused by movement of the piston.

9. The crop machine according to claim 1 wherein said electronic control system is programed to be responsive to a movement signal generated by movement of the header relative to the support vehicle and not to changes in pressure in the chamber which changes are caused by movement of the piston.

10. A crop machine comprising:
a support vehicle for running over ground;
a crop header including a crop engaging system and at least one ground engaging component for providing a supporting force from the ground as the vehicle runs over the ground so as to cause ground contact;
a support apparatus for supporting the crop header relative to the vehicle for upward and downward floating movement of the crop header so that a proportion of a supporting force to counterbalance the weight of the crop header is supplied by a lifting force from the support apparatus and a remaining portion is supplied by the ground engaging component caused by ground pressure on the ground;
the support apparatus comprising:
at least one hydraulic float cylinder having a piston movable in the cylinder arranged such that movement of the piston relative to the cylinder causes said lifting force from the support apparatus to be applied to the crop header;
a hydraulic lift system containing a hydraulic fluid under a hydraulic pressure which is set for applying a force to a side of the piston in said cylinder in a direction to lift the crop header;
the hydraulic lift system in operation being arranged to provide a hydraulic pressure defining a first lifting force;
a supplementary pressure system comprising a chamber and a fluid supply supplying fluid under pressure to the chamber so that the chamber applies a supplementary force to the crop header so that a combination of the first lifting force and the supplementary force provides said lifting force from the support apparatus and acts to support the header while applying said ground pressure on the ground;
and an electronic control system for controlling the lifting force from the support apparatus in response to at least one input which determines a required lifting force;
wherein the electronic control system is arranged to supply to the supplementary pressure system a control signal so as to vary the supplementary force;
wherein movement of the piston in the cylinder, caused by the movement of the header, effects changes in the first lifting force;
and wherein the electronic control system is arranged to modify the control signal in response to said changes in the first lifting force caused by said movement of the piston.

11. The crop machine according to claim 10 wherein the hydraulic lift system is

Assignees

• Macdon Ind Ltd

Inventors

• Dunn James Thomas
• Leverick Graham Michael
• Lyons Russell George
• Shearer Bruce Robert
• Boch Kyle Edward

Classifications

• F15B2211/7051

  Linear output members · CPC title

• F15B2211/5151

  being connected to a pressure source and a directional control valve · CPC title

• F15B21/14

  Energy-recuperation means · CPC title

• A01D41/141 Primary

  Automatic header control · CPC title

• F15B2211/3059

  having multiple valves for multiple output members · CPC title