wedge
Enable an AI agent to recognise a physical wedge, assess its fitness for a specific contact arrangement, and decide whether and how it may be inserted, loaded, adjusted or removed.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an AI agent to recognise a physical wedge, assess its fitness for a specific contact arrangement, and decide whether and how it may be inserted, loaded, adjusted or removed.
A wedge is a rigid tapered body - classically a triangular prism, equivalently two inclined planes joined at an apex - that converts a force driven toward the thin end into larger normal forces on its faces, and is counted among the classical simple machines.
It can be Match the wedge's entry thickness, taper and bearing width to a proposed gap and working role.; Orient and insert the wedge using an evidenced driving method and travel limit.; Adjust separation, preload or restraint by changing engagement within established limits.; Assess whether retention or a secondary restraint is required for the proposed loading.; Inspect working faces and driving features to decide whether continued use is supported.; Plan unloading and withdrawal while accounting for supported objects and stored force..
Distinguishing features
Identify a working region whose thickness increases along an intended insertion direction, rather than relying on a triangular silhouette alone.
Establish whether advancing the taper between contacts is intended to change separation or contact force; an inclined surface used only as a travel path is more plausibly a ramp.
Check whether restraint or adjustment depends on the taper; a constant-thickness spacer does not meet this draft's wedge criterion.
Determine whether the taper is a separately recognised object or only the working geometry of a blade, chisel or other tool; registry ownership of these cases remains unresolved.
Scope
+ Functional taper, entry edge or tip, bearing faces and driving or extraction features
+ Material and construction as they affect the wedge's working behaviour
+ Contact arrangement, insertion direction and available engagement
+ Evidence for load capacity, displacement, retention and removal limits
+ Wear, damage and application-specific readiness
- The complete machine, joint or support assembly containing the wedge
- The full material behaviour and damage state of the object being split or restrained
- Hammers, presses and other devices that drive the wedge
- Screws, cams and levers whose primary working mechanism is not wedge insertion
- Objects called wedges solely because of their appearance, including food portions and diagram sectors
Characteristics
- Working role
- splitting | separating | lifting | tightening | locating | restraining | other | unknown Determines which outcomes, contact conditions and failure modes need assessment.
- Taper profile
- single-face taper | opposed-face taper | curved taper | compound taper | other | unknown Identifies how thickness changes through insertion and which surfaces can carry load.
- Working taper angle
- degrees, with reference faces and local or included angle identified Supports assessment of displacement, driving demand and possible back-driving.
- Thickness along insertion path
- mm at stated distances from the entry edge or tip Establishes entry clearance and available separation over usable travel.
- Effective bearing width
- mm over the engaged working region Helps assess contact concentration and fit within the receiving space.
- Material and construction
- documented material, treatment, grain or reinforcement orientation, and construction type; unknown where unverified Informs susceptibility to deformation, fracture, crushing or surface damage.
- Contact arrangement
- working face to contacted object, with contact location and intended load direction Connects the wedge's geometry to its actual mechanical role.
- Insertion depth
- mm from an identified entry datum Shows current engagement and remaining usable adjustment.
- Retention condition
- externally retained | friction-dependent | observed migration | unassessed Determines whether the wedge may move or be expelled under the present conditions.
- Application limit evidence
- manufacturer instruction, test result or engineering assessment tied to a stated contact and loading arrangement Prevents a capacity established for one arrangement from being treated as universal.
- Working-surface and driving-end condition
- observed wear, rounding, burrs, mushrooming, cracks, crushing, deformation or contamination, with location and extent Supports decisions about engagement, driving, withdrawal and retirement.
Also called
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 5 bundles · 9 layers · 16 findings · 27 questions.
Working taper The geometry that makes this object function as a wedge and bounds its useful engagement.
A wedge must be recognised through its working taper, and its fit cannot be judged from overall dimensions alone.
Taper identity
Identify the active taper and its intended mechanical role.
Active wedge region
Record the region whose increasing thickness is intended to create separation, contact force or restraint.
- Which faces form the working taper, and in which direction does effective thickness increase? definition
- Does the object's intended function depend on advancing this taper, or is its wedge-like shape incidental? boundary
Entry and travel
Establish the dimensions controlling initial entry and useful insertion.
Usable taper envelope
Record entry thickness, thickness profile, bearing width and the portion of travel available for working contact.
- What are the entry thickness, taper angle or profile, and effective width at the intended engagement? measurement
- Where must insertion stop because the taper ends, a shoulder interferes or the receiving space runs out? boundary
Contact and driving How the wedge meets the receiving objects and how insertion or extraction force reaches it.
The same wedge geometry can behave differently when contact alignment, support or driving method changes.
Bearing arrangement
Identify the working contacts and their alignment with the intended action.
Engaged contact pair
Record the objects bearing on the wedge, the engaged face regions and any unintended edge contact.
- Which objects contact each working face, and where are the actual bearing regions? measurement
- Does the proposed orientation produce the intended separation or restraint without unsupported twisting or edge loading? action
Force application
Identify permitted driving and extraction interfaces.
Driving and withdrawal features
Record how force may be applied to advance or retrieve this wedge, including access constraints.
- What instructions or design evidence establish whether the wedge may be struck, pressed, hand-inserted or drawn by a mechanism? provenance
- Which face, head, hole or other feature accepts driving or extraction force, and will it remain accessible after insertion? action
Load and retention The supported operating envelope and the conditions governing wedge migration.
Useful force transmission and resistance to backing out require evidence tied to a particular wedge and contact arrangement.
Working envelope
Connect intended loading and movement to applicable evidence.
Supported load and displacement
Record substantiated limits for the proposed role without assigning an unsupported universal capacity.
- What source establishes allowable loading, insertion force or displacement, and what material, contact and engagement conditions does it assume? provenance
- What load, engagement depth and required movement describe the proposed use? measurement
- Does the proposed use remain within the evidenced conditions, or does it require further assessment? action
Migration and restraint
Assess the potential for backing out, slipping or expulsion.
Retention basis
Record how position is maintained and whether the supporting evidence applies to current surfaces and loading.
- Is retention supplied by a positive restraint, assessed frictional contact or an unverified assumption? definition
- What evidence addresses retention under the relevant surface condition, vibration and changes in load direction? provenance
- What restraint or operating restriction is required if migration cannot be ruled out? action
Damage and release Changes to wedge geometry or integrity and the conditions for withdrawing a loaded wedge.
Damage can undermine engagement or driving, while withdrawal can release the very separation or restraint the wedge provides.
Working feature integrity
Assess deterioration of the entry region, bearing faces and force-application features.
Damage affecting wedge action
Record defects by location and their implications for entry, bearing, driving and retention.
- What rounding, cracking, mushrooming, crushing, bending or surface contamination is present at the working and driving regions? measurement
- Which documented acceptance criteria determine whether those observations permit reuse, repair or retirement? provenance
Controlled withdrawal
Identify what depends on the wedge before reducing engagement.
Release dependencies
Record the supported load, restraint or stored deformation that may change when the wedge is removed.
- Which objects could move, close, fall or spring back as wedge engagement decreases? boundary
- What unloading, substitute support or restraint must be established before withdrawal? action
- What evidenced extraction method applies if the wedge is jammed or its normal withdrawal feature is inaccessible? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- splitting wedge (wood, stone, masonry)
- holding or stopping wedge (door wedge, wheel chock)
- cutting-edge wedge (the taper of a knife, axe, or chisel)
- tapered machine key (thin taper key, gib-head key, tangential key)
- tapered shim or packing wedge (alignment and leveling)
- cotter and gib-and-cotter fastening wedge
- interproximal dental wedge
- soil-engaging wedge (plowshare, ripper tooth)
- Which of these kinds and varieties hold for the sense of wedge this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikipedia - Wedge (mechanical device) - Canonical English article for the simple-machine / tool sense in PHY.OBJ; do not confuse with golf, geology, or the exterior-algebra wedge product.
- ISO 2491 designation - thin taper key specified by width × height × length against a matching keyway - Names the machine-key kind of wedge, not a hand splitting wedge.
- Which of these identifiers and schemes hold for the sense of wedge this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- ISO 2491 Thin taper keys with or without gib head and their corresponding keyways (International Organization for Standardization)
- 29 CFR 1926.301(c) Hand tools - impact tools such as wedges shall be kept free of mushroomed heads (Occupational Safety and Health Administration, United States)
- 29 CFR 1910.178(k) Powered industrial trucks - wheel chocks (and related trailer-separation chocking practice) (Occupational Safety and Health Administration, United States)
- Which of these standards and regulation hold for the sense of wedge this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Driven into a log or block of stone with a sledge to split along grain or a cleavage plane.
- Placed under a door leaf or a parked wheel to hold position by friction on the taper.
- Ground into the bevel of knives, axes and chisels so the edge itself is a thin wedge.
- Fitted in a shaft keyway as a taper or gib-head key to lock a hub and transmit torque.
- Slid as a tapered shim under a machine foot or bearing housing to set height and alignment.
- Inserted between teeth in restorative dentistry to separate contacts and adapt a matrix band.
- Formed as the share of a plough or the tooth of a ripper to open soil.
- Which of these real-world use hold for the sense of wedge this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- included (apex) angle - about 10-20 for cutting edges; about 20-40 for hand splitting wedges; blunter for holding chocks - degree
- length (hand splitting wedge) - 150-300 - mm
- mass (hand steel splitting wedge) - 0.5-4 - kg
- ideal mechanical advantage (length / thickness) - about 5-15 for common splitting wedges, before friction - 1
- struck-face hardness (tool-steel splitting wedge) - about 50-60 - HRC
- Which of these typical measurements hold for the sense of wedge this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Mushrooming of the struck face, then chip-off of steel fragments toward the user.
- Brittle fracture or spalling if the wedge is too hard or badly heat-treated.
- Slip-out under load when faces are oily, icy, or the included angle is too blunt for the friction available.
- Uncontrolled split or fly-out of the workpiece (log, masonry, frozen ground).
- Pinch, crush, or puncture injuries as the taper is driven between parts.
- Loss of holding force in a door wedge or wheel chock, allowing a door to slam or a vehicle to roll.
- Key/cotter walk-out or fretting in a shaft assembly if the taper and end-float are wrong.
- Which of these failure modes and hazards hold for the sense of wedge this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- The same simple machine is Keil in German, coin in French, and kusabi (楔) in Japanese; trade catalogues in those languages rarely file the object under the English word wedge.
- British usage still calls a driven fastening taper a cotter; U.S. shop practice more often says taper key, gib key, or (loosely) pin.
- Central European firewood practice often pairs a splitting axe with a steel Keil; North American practice commonly pairs a maul with a separate steel splitting wedge.
- In English, golf wedge (pitching, sand, lob) is a club class, not a simple machine; that sense should not be merged with PHY.OBJ tool wedges.
- Which of these regional variation hold for the sense of wedge this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- inclined plane - An inclined plane is usually a fixed ramp the load moves along; a wedge is the taper that is driven into or under the load.
- screw - A screw is an inclined plane wrapped as a helix; a wedge's generating curve is linear, not helical.
- parallel shim - A parallel shim has constant thickness and sets one discrete height; a wedge shim is tapered and adjusts height by how far it is inserted.
- chisel - A chisel is a handled cutting tool with a ground bevel meant to cut or pare; a splitting wedge is typically a free prism struck on the poll, with a broader included angle and no cutting handle.
- froe - A froe has a blade and a handle at right angles and is worked by mallet along the grain; it is not a free triangular striking prism.
- cam - A cam produces displacement by rotation of a varying radius; a wedge produces displacement by linear insertion of a taper.
- nail or spike - The point uses wedge action, but the object is classified as a slender fastener by aspect ratio and by retention in the hole, not as a simple-machine wedge.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of wedge this model covers, and on what evidence? provenance
Sources
- Wedge (mechanical device) - Wikipedia, Wikimedia Foundation - Classification as a simple machine; splitting, lifting, holding and cutting uses; relation to the inclined plane.
- 29 CFR 1926.301 Hand tools - Occupational Safety and Health Administration / U.S. eCFR - Struck wedges must be kept free of mushroomed heads; construction-site impact-tool hazard.
- ISO 2491, Thin taper keys with or without gib head and their corresponding keyways - International Organization for Standardization - Standardized shaft keys that work as fastening wedges; dimensions and keyway geometry.
- wedge (mechanics) - Encyclopædia Britannica - Simple-machine definition and the force-multiplying action of a taper.
What the second pass must settle
- Does vr.tr.wedge denote a mechanical wedge specifically, or a broader geometric class of physical objects?
- Which existing registry entries or world models own tapered shims, chocks, splitting wedges and wedge-shaped working parts of tools?
- Which authoritative sources establish operating and inspection limits for the wedge families included in the eventual scope?
- How should retention be assessed when friction, surface condition or vibration is unknown?
- Should paired or adjustable wedge mechanisms be represented as wedge instances in an assembly, or owned entirely by a neighbouring mechanism model?