Rake frame with hinge joint connecting front and rear frame sections

Calvin Mohr, Ogden, IL (US)

USPTO: us-12628742 · published 2026-05-19 · patents · A01D 78/1014· A01D 78/14· A01D 78/146

Rake frame with hinge joint connecting front and rear frame sections

Calvin Mohr, Ogden, IL (US) This is my paper

Pith reviewed 2026-05-20 19:31 UTC · model grok-4.3

classification patents A01D 78/1014A01D 78/14A01D 78/146

keywords rake framehinge jointagricultural rakeadjustable framehay rakefront rear sectionswheel rake

0 comments

The pith

Four non-coaxial hinges plus one adjustment element allow both angle and offset of a rake's rear frame section to be changed in one operation.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The patent presents a rake frame subassembly in which a front section and a rear section are joined by a hinge joint that contains four hinges whose rotation axes do not coincide. An adjustment element changes the distance between two of those axes. The arrangement is claimed to let an operator alter both the relative orientation and the relative position of the rear rake wheels simply by rotating the rear section and operating the adjustment element.

Core claim

The hinge joint connects the front and rear frame sections and is configured to enable both an orientation and a position of the rear frame section relative to the front frame section to be adjusted by changing orientation and translating using the adjustment element.

What carries the argument

Four-hinge joint whose rotation axes are mutually non-coaxial, combined with an adjustment element that varies the distance between the first and fourth hinge axes.

If this is right

Rear rake wheels can be set to different working angles without separate pivot locks or additional actuators.
Lateral or longitudinal offset of the rear section can be fine-tuned during the same adjustment step.
The frame can accommodate varying crop rows or tractor paths by a single mechanical change.
Fewer separate adjustment mechanisms are required compared with conventional telescoping or sliding rake arms.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

The design may reduce overall part count and maintenance points on pull-type rakes.
Field adjustment time during haying could decrease if operators no longer need to loosen and retighten multiple clamps.

Load-bearing premise

The four non-coaxial hinges and single adjustment element remain mechanically stable and free of binding under typical field loads and repeated adjustment cycles.

What would settle it

A working prototype subjected to repeated adjustment cycles and normal hay-raking loads exhibits binding, excessive play, or structural failure at any of the hinge axes.

read the original abstract

1 . A rake frame subassembly comprising: a front frame section configured to support at least one front rake wheel; a rear frame section configured to support at least one rear rake wheel; and a hinge joint having: a first hinge and a second hinge, each connected to, attached to, integral with, configured to connect to, or configured to be integral with the front frame section; and a third hinge and a fourth hinge, each connected to, attached to, integral with, configured to connect to, or configured to be integral with the rear frame section, each of the first hinge, second hinge, third hinge, and fourth hinge having an axis of rotation that does not overlay an axis of rotation of others of the first hinge, second hinge, third hinge, and fourth hinge, the hinge joint comprising an adjustment element configured to adjust a distance between a rotation axis of the first hinge and a rotation axis of the fourth hinge, the hinge joint connecting or configured to connect the front frame section and the rear frame section and configured to: enable both an orientation of the rear frame section relative to the front frame section and a position of the rear frame section relative to the front frame section to be adjusted by changing an orientation of the rear frame section relative to the front frame section and translating the rear frame section relative to the front frame section using the adjustment element; or enable a position of the rear frame section relative to the front frame section to be adjusted by translating the rear frame section relative to the front frame section using the adjustment element.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

Utility patent on a four-hinge rake frame joint with variable inter-axis distance; the geometry is described but never shown to move freely under load.

read the letter

This is a utility patent for an agricultural rake frame subassembly. The core claim is a hinge joint using four non-coaxial hinges plus one adjustment element that changes the distance between two of the rotation axes. That change is said to let the operator adjust both the angle and the fore-aft position of the rear frame section relative to the front section. The text is written in standard patent language and stays internally consistent; no contradictory statements appear in the claims or description. The arrangement is not a trivial extension of the single-pivot or parallel-link frames that dominate the cited classifications, so the specific four-hinge layout with variable spacing is the actual novelty on offer. Beyond that, the document supplies nothing else—no load calculations, no kinematic model, no prototype photos, and no field-test results. The stress-test concern is therefore on target: once the axes are all distinct and one inter-axis distance becomes variable, it is not obvious that the linkage stays mobile across the intended range of adjustments rather than locking or binding. A patent examiner can grant the claim on the basis of the written description alone, but anyone who wants to build or improve the mechanism still has to solve the kinematics and structural questions from scratch. The work is aimed at implement designers and prior-art searchers in agricultural machinery. It does not contain results that would interest a research reading group or that I would cite in a mechanics or mechanisms paper. Because it is a standalone mechanical claim rather than a verified design or a scientific finding, I would not send it out for peer review in an academic venue.

Referee Report

1 major / 0 minor

Summary. The manuscript presents a rake frame subassembly comprising front and rear frame sections joined by a hinge joint that incorporates four non-coaxial hinges together with an adjustment element capable of varying the distance between the rotation axes of the first and fourth hinges. The central claim is that this arrangement permits the rear frame section to be adjusted relative to the front section in both orientation and position (or position alone) by rotation and translation effected through the adjustment element.

Significance. If the claimed linkage proves kinematically mobile and mechanically stable, the design could offer a compact means of achieving compound adjustments in agricultural rakes without additional actuators. The manuscript supplies no kinematic analysis, workspace mapping, load data, or prototype results, so the practical significance remains unestablished.

major comments (1)

Claim 1: the assertion that the four non-coaxial hinges plus variable inter-axis distance adjustment element together enable independent control of both relative orientation and relative position is presented without any supporting kinematic reasoning, instantaneous-DOF calculation, or demonstration that the mechanism remains mobile rather than locking or binding across the intended agricultural adjustment range.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the detailed reading and constructive comment. The document is a U.S. patent specification whose primary purpose is to define the structural elements and functional capabilities of the claimed rake-frame subassembly. Below we respond directly to the single major comment.

read point-by-point responses

Referee: Claim 1: the assertion that the four non-coaxial hinges plus variable inter-axis distance adjustment element together enable independent control of both relative orientation and relative position is presented without any supporting kinematic reasoning, instantaneous-DOF calculation, or demonstration that the mechanism remains mobile rather than locking or binding across the intended agricultural adjustment range.

Authors: We agree that the patent text contains no explicit instantaneous-DOF analysis, Grübler–Kutzbach count, or numerical workspace map. Patent specifications are not required to furnish such engineering calculations; enablement is satisfied by a clear structural description together with a statement of the intended kinematic result. The four non-coaxial hinges combined with the variable-length adjustment element constitute a spatial mechanism whose mobility follows directly from the fact that the adjustment element changes the distance between two rotation axes, thereby converting a portion of the rotational freedom into translational freedom. This functional description is sufficient for patent purposes. Nevertheless, if the examiner or the referee believes a short kinematic paragraph would strengthen the file, we are prepared to add one sentence in the detailed description that states the mechanism possesses one degree of freedom when the adjustment element is actuated and remains mobile throughout the agricultural range of rake angles and offsets. revision: no

Circularity Check

0 steps flagged

No circularity: standalone mechanical claim with no derivations or self-referential predictions

full rationale

The document is a utility patent whose sole content is a structural claim describing a four-hinge joint plus adjustment element. No equations, fitted parameters, predictions, first-principles derivations, or self-citations appear anywhere in the specification or claims. The central statement simply enumerates kinematic degrees of freedom that the inventor asserts the geometry provides; nothing reduces by construction to an input that was itself defined by the output. Consequently the circularity score is 0.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No mathematical axioms, free parameters, or invented physical entities are invoked; the document is an engineering design specification.

pith-pipeline@v0.9.0 · 5832 in / 984 out tokens · 24962 ms · 2026-05-20T19:31:50.195978+00:00 · methodology

discussion (0)

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

IndisputableMonolith/Foundation/RealityFromDistinction reality_from_one_distinction unclear

?

unclear
Relation between the paper passage and the cited Recognition theorem.

A rake frame subassembly comprising: a front frame section configured to support at least one front rake wheel; a rear frame section configured to support at least one rear rake wheel; and a hinge joint having: a first hinge and a second hinge... the hinge joint comprising an adjustment element configured to adjust a distance between a rotation axis of the first hinge and a rotation axis of the fourth hinge

What do these tags mean?

matches: The paper's claim is directly supported by a theorem in the formal canon.
supports: The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends: The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses: The paper appears to rely on the theorem as machinery.
contradicts: The paper's claim conflicts with a theorem or certificate in the canon.
unclear: Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.