Skid plate

Markus Petersson, Jönköping (SE); Martin Elonsson, Huskvarna (SE); Peter Ahlin, Jönköping (SE); Ronny Olsen, Nässjö (SE); Svante Larsson, Eksjö (SE)

USPTO: us-12628736 · published 2026-05-19 · patents · A01D 34/828· A01D 34/008· A01D 34/73· A01D 2101/00

Skid plate

Martin Elonsson, Huskvarna (SE) , Ronny Olsen, Nässjö (SE) , Svante Larsson, Eksjö (SE) , Peter Ahlin, Jönköping (SE) , Markus Petersson, Jönköping (SE) This is my paper

Pith reviewed 2026-05-20 16:01 UTC · model grok-4.3

classification patents A01D 34/828A01D 34/008A01D 34/73A01D 2101/00

keywords skid platerobotic lawnmowerbent edgecircular segmentground clearance

0 comments

The pith

A skid plate for robotic lawnmowers has a transversely bent edge whose cross-section is a circular segment of 1-30 mm radius, with the outer peripheral edge lying in one plane.

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

The patent describes a skid plate consisting of an approximately circular plate with a central hub opening and attachment means. An edge portion is bent out of the main plane so that its outer rim remains flat in a single plane. The bent edge has a partly circular cross-section whose radius falls between 1 and 30 mm. This geometry is presented as the defining feature of the new skid plate. A reader would care because the shape is asserted to affect how the mower interacts with ground obstacles and surface irregularities.

Core claim

The skid plate comprises an approximately circular plate with a central opening for a hub and attachment means; an edge portion of the plate is bent transversely to the main plane, the outer peripheral edge extends in a single plane, and the cross-section of the edge portion is at least partly a circle segment having a radius of 1 to 30 mm.

What carries the argument

The transversely bent edge portion whose cross-section is a circular segment of 1-30 mm radius and whose outer rim lies in one plane.

If this is right

The mower can ride over low obstacles with reduced risk of catching or deforming the plate edge.
Manufacturing can use a simple bending or rolling operation to produce the circular-segment profile.
The single-plane outer rim maintains consistent ground clearance around the entire circumference.
Attachment to the mower chassis remains compatible with existing hub and fastener layouts.

Where Pith is reading between the lines

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

The radius window may have been chosen to balance stiffness against the risk of the edge digging into soft turf.
If the circular-segment profile reduces stress concentration, similar edges could be applied to other low-clearance vehicle guards.
Field trials measuring mower uptime on uneven lawns would directly test the claimed practical benefit.

Load-bearing premise

The stated radius range and single-plane outer edge supply a functional advantage in durability or obstacle clearance that earlier skid-plate shapes lack.

What would settle it

A side-by-side wear or impact test on identical mowers fitted with the described edge versus a conventional flat or differently radiused edge that shows no measurable difference in damage, clearance height, or service life.

read the original abstract

1 . A skid plate for a robotic lawnmower, the skid plate comprising an approximately circular plate with a central opening, for a hub, and means of attachment, whereby the skid plate is attachable to said robotic lawnmower, wherein an edge portion of the circular plate is bent to extend transversally to a main plane of the circular plate, and an outer peripheral edge thereof extends in a single plane, wherein a cross section of the edge portion has, at least partly, a shape of a circle segment, and wherein the circle segment has a radius of 1 to 30 mm.

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

A narrow utility patent on a bent-edge skid plate geometry for robotic mowers, with no data or analysis attached.

read the letter

This document is a standard utility patent claim, not a research paper. The core specification is an approximately circular skid plate whose outer edge portion is bent transversally into a circle-segment cross-section (radius 1–30 mm) that lies in a single plane. That geometry is presented as the invention for attachment to a robotic lawnmower hub. The drafting is clear and the claim language is conventional for mechanical patents, which is the main thing it does competently. Beyond that, nothing is shown. No stress analysis, no wear or impact tests, no comparison with existing flat or rolled-edge plates, and no derivation for the radius bounds appear anywhere. The functional advantages (clearance, durability, manufacturability) are simply asserted. Sheet-metal forming of circular segments and single-plane edges is routine in guards and housings across many industries, so the combination does not look novel outside the narrow application. Because the submission supplies only the geometric claim, any evaluation of performance or advantage rests on untested assumptions. For a design engineer or patent attorney working on outdoor power equipment this might be worth a quick look for prior-art purposes. For anyone expecting evidence, modeling, or comparative results it offers nothing. I would not bring it to a reading group, would not cite it, and would not send it to scientific peer review; it belongs in the patent-examination track, not a journal.

Referee Report

1 major / 1 minor

Summary. The manuscript is a utility-patent claim for a skid plate intended for robotic lawnmowers. It specifies an approximately circular plate having a central opening for a hub and attachment means, with an edge portion bent transversally to the main plane such that the outer peripheral edge lies in a single plane and the edge cross-section is at least partly a circular segment of radius 1–30 mm.

Significance. If the stated geometry confers measurable advantages in durability, obstacle clearance, or ease of manufacture, the design could constitute a modest incremental improvement in robotic-mower underbody protection. Absent any performance data, stress analysis, or comparison with prior geometries, however, the engineering significance remains limited to the narrow geometric specification itself.

major comments (1)

The central claim (Abstract and Claim 1) asserts functional benefits implicitly through the choice of radius range and single-plane edge, yet supplies neither comparative testing nor mechanical analysis to establish that these parameters improve performance relative to existing skid-plate designs.

minor comments (1)

The manuscript is written entirely in claim language; conversion to a conventional technical-paper format would require an introduction, background on existing skid plates, and a description of embodiments beyond the single independent claim.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the constructive comment. The manuscript is a utility-patent claim whose novelty resides in a precisely defined geometry; we address the request for supporting analysis below and clarify the intended scope of the filing.

read point-by-point responses

Referee: The central claim (Abstract and Claim 1) asserts functional benefits implicitly through the choice of radius range and single-plane edge, yet supplies neither comparative testing nor mechanical analysis to establish that these parameters improve performance relative to existing skid-plate designs.

Authors: The claim is directed solely to the novel geometric configuration itself (bent peripheral edge of circular-segment cross-section lying in a single plane). No performance metrics or comparative advantages are asserted in the claim language or abstract; any functional benefit is an inherent consequence of the geometry rather than a separately claimed technical effect. In a utility-patent context, enablement and novelty are satisfied by the explicit dimensional and configurational limitations; empirical validation or FEA is not required to support the claim as drafted. revision: no

Circularity Check

0 steps flagged

No significant circularity

full rationale

The document is a utility patent whose sole content is a geometric product claim defining a skid-plate shape (bent edge portion with circle-segment cross-section of radius 1–30 mm and single-plane outer periphery). No derivation, prediction, fitted parameter, or load-bearing premise is asserted; the text contains neither equations nor citations. Consequently no step reduces to its own inputs by construction and the circularity score is zero.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The patent rests on the domain assumption that a bent circular-segment edge of the stated radius range improves mower performance or durability; no free parameters, invented physical entities, or additional axioms are introduced.

axioms (1)

domain assumption A transversally bent edge whose outer periphery lies in a single plane and whose cross-section is a circle segment of 1-30 mm radius provides functional benefit for robotic-lawnmower skid plates.
Implicit premise required for the claim to be useful; no supporting evidence is given in the abstract.

pith-pipeline@v0.9.0 · 5687 in / 1226 out tokens · 43787 ms · 2026-05-20T16:01:06.756722+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.

an edge portion of the circular plate is bent to extend transversally to a main plane of the circular plate, and an outer peripheral edge thereof extends in a single plane, wherein a cross section of the edge portion has, at least partly, a shape of a circle segment, and wherein the circle segment has a radius of 1 to 30 mm

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.