Draper header with automatic reel to cutter bar clearance
Pith reviewed 2026-05-27 16:31 UTC · model grok-4.3
The pith
A draper header uses wing-angle sensors to trigger hydraulic reel lift and prevent cutter-bar contact during frame flex.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
When the wing sensing system registers that one header frame section has pivoted downward relative to another, the hydraulic system is actuated to raise the reel support arms, thereby increasing the distance between the crop pick-up reel and the cutter bar assembly before contact can occur.
What carries the argument
Wing sensing system that measures pivot angles between header frame sections and directly commands the hydraulic circuit lifting the reel support arms.
Load-bearing premise
The sensors and hydraulics respond fast enough, under every field speed and terrain change, to lift the reel before physical contact happens.
What would settle it
A controlled test on uneven ground in which the reel still strikes the cutter bar after the wing sensors have triggered the lift command.
read the original abstract
1 . A draper header for use in a field to harvest agricultural crops, the draper header comprising: a header frame with a front portion and a rear portion each extending laterally between opposite ends thereof, the header frame divided into a plurality of header frame sections pivotable upwardly and downwardly relative to each other for contouring to the field; a cutter bar assembly extending across the front portion of the header frame and flexible with the plurality of header frame sections for cutting the crops to be harvested; a plurality of reel support arms pivotally coupled to the rear portion of the header frame and extending generally above the front portion of the header frame; at least one crop pick-up reel rotatably supported by the plurality of reel support arms and positioned generally above the cutter bar assembly for engaging the crops to be harvested; a reel height position sensor for determining a distance between the at least one crop pick-up reel and the cutter bar assembly; a wing sensing system operatively coupled to the header frame for sensing pivoting of the plurality of header frame sections relative to each other; and a hydraulic system adapted for raising and lowering the plurality of reel support arms, wherein the hydraulic system is actuated to raise the at least one crop pick-up reel when the wing sensing system detects that one of the plurality of header frame sections pivots downwardly relative to another of the plurality of header frame sections for preventing contact of the at least one crop pick-up reel with the cutter bar assembly; wherein the wing sensing system detects a pivot angle of each of the plurality of header frame sections relative to the other of the plurality of header frame sections, and wherein the hydraulic system is
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript describes a draper header comprising a multi-section pivotable frame, a flexible cutter-bar assembly, reel support arms with an integrated reel-height position sensor, a wing-angle sensing system, and a hydraulic circuit that automatically raises the reel support arms upon detection of downward wing pivoting, with the stated purpose of maintaining reel-to-cutterbar clearance.
Significance. If the functional claim is enabled, the design would constitute a practical automation feature for contour-adaptive headers, reducing operator workload and risk of reel damage on uneven terrain.
major comments (2)
- [Claim 1] Claim 1 (and the corresponding description): the prevention assertion—that wing sensing plus hydraulic actuation will raise the reel before contact occurs—rests on an unverified performance assumption; no sensor resolution, pivot-rate threshold, hydraulic flow specification, arm inertia, or kinematic envelope relating wing angle change to reel-cutterbar gap is supplied.
- [Claim 1] The reel height position sensor is introduced but its output is never shown to participate in the control law that triggers the hydraulic raise; the actuation description refers only to the wing sensing system.
minor comments (1)
- [Abstract] The abstract text terminates mid-sentence (“and wherein the hydraulic system is”).
Simulated Author's Rebuttal
We thank the referee for the constructive comments on the functional description and control logic. We address each major comment below with reference to the patent disclosure.
read point-by-point responses
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Referee: [Claim 1] Claim 1 (and the corresponding description): the prevention assertion—that wing sensing plus hydraulic actuation will raise the reel before contact occurs—rests on an unverified performance assumption; no sensor resolution, pivot-rate threshold, hydraulic flow specification, arm inertia, or kinematic envelope relating wing angle change to reel-cutterbar gap is supplied.
Authors: The disclosure is a utility patent that sets forth the inventive combination of wing-angle sensing and automatic hydraulic reel lift to maintain clearance. Patent practice requires only an enabling description of the claimed system architecture rather than quantitative implementation parameters; the latter are regarded as within the ordinary skill of a controls or hydraulics engineer once the functional interconnection is taught. No performance data or kinematic envelope was therefore included. revision: no
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Referee: [Claim 1] The reel height position sensor is introduced but its output is never shown to participate in the control law that triggers the hydraulic raise; the actuation description refers only to the wing sensing system.
Authors: We agree that the claim language and supporting description condition hydraulic actuation exclusively on the output of the wing sensing system. The reel-height sensor is recited as an element of the header but is not required by the recited control law. This accurately reflects the minimal inventive concept; if the examiner or referee prefers, the sensor can be removed from the independent claim or its optional use can be clarified in dependent claims. revision: partial
Circularity Check
No derivation chain or equations present; purely descriptive mechanical patent
full rationale
The document is a utility patent specification describing a draper header mechanism with sensors and hydraulics. It contains no mathematical derivations, fitted parameters, predictions, uniqueness theorems, or ansatzes. The central functional claim is an engineering assertion about system behavior rather than any reduction of an output to its own inputs by construction. No steps match any of the enumerated circularity patterns.
discussion (0)
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