A pawl is a movable lever that engages a fixed component to either prevent movement in one direction or restrain it altogether. As such, it is a type of

latch A latch or catch (called sneck in Northern England and Scotland) is a type of mechanical fastener that joins two or more objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the ...

and can also be considered a type of

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...

. It typically consists of a

spring-loaded A spring is a device consisting of an elastic but largely rigid material (typically metal) bent or molded into a form (especially a coil) that can return into shape after being compressed or extended. Springs can store energy when compresse ...

lever that engages a mating component at a steep enough angle to restrain it. Pawls are often tapered, being widened at their pivot for anchoring and narrow at their tip.

Applications

;Anchor windlass: A pawl is used in an

anchor windlass A windlass is a machine used on ships that is used to let-out and heave-up equipment such as a ship's anchor or a fishing trawl. On some ships, it may be located in a specific room called the windlass room. An anchor windlass is a machine tha ...

to prevent a free-spooling chain by grabbing and snubbing an individual link. Similar mechanisms include a Devil's claw, or a claw and dog. ;Ratchet: A pawl is used in combination with a

ratchet Ratchet may refer to: Devices * Ratchet (device), a mechanical device that allows movement in only one direction * Ratchet effect in sociology and economics * Ratchet, metonymic name for a socket wrench incorporating a ratcheting device * Ratc ...

gear in

socket wrench A socket wrench (or socket spanner) is a type of spanner (or wrench in North American English) that uses a closed ''socket'' format, rather than a typical open wrench/spanner to turn a fastener, typically in the form of a nut or bolt. The most ...

es, bicycle

freehub A freehub is a type of bicycle Bicycle wheel#Hub, hub that incorporates a ratchet (device), ratcheting mechanism. A set of sprockets (called a "cassette (bicycle part), cassette") is mounted onto a Spline (mechanical), splined shaft of the freehu ...

winch A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension (physics), tension of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a Bobb ...

es, ratchet reels for diving,

fishing Fishing is the activity of trying to catch fish. Fish are often caught as wildlife from the natural environment (Freshwater ecosystem, freshwater or Marine ecosystem, marine), but may also be caught from Fish stocking, stocked Body of water, ...

, and many other applications. ;Ladder:

Dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...

s (in the form of pawls) are used on

extension ladder A ladder is a vertical or inclined set of rungs or steps commonly used for climbing or descending. There are two types: rigid ladders that are self-supporting or that may be leaned against a vertical surface such as a wall, and rollable ladd ...

s to temporarily anchor their sections to one-another. ;Table saw: Pawls are used on

table saw A table saw (also known as a sawbench or bench saw in England) is a woodworking tool, consisting of a circular saw blade, mounted on an mandrel, arbor, that is driven by an electric motor (directly, by belt, by cable, or by gears). The drive ...

s to prevent a workpiece being sawn from kicking back. ;Transmission: A

parking pawl A parking pawl is a device fitted to a motor vehicle's automatic transmission that locks up the transmission when the transmission shift lever selector is placed in the Park position. "Park" is the first position of the lever (topmost on a col ...

is a device in an automobile

automatic transmission An automatic transmission (AT) or automatic gearbox is a multi-speed transmission (mechanics), transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. The 1904 ...

which prevents it from moving when the vehicle is parked .Keith Santini, Kirk Vangelder, ''Automotive Automatic Transmissions and Transaxles'', p. 174, Jones & Bartlett Learning, 2017 . ;

Revolver A revolver is a repeating handgun with at least one barrel and a revolving cylinder containing multiple chambers (each holding a single cartridge) for firing. Because most revolver models hold six cartridges before needing to be reloaded, ...

s: The hand (pawl) indexes the

cylinder A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infinite ...

References

{{reflist Mechanisms (engineering) Fasteners de:Sperrklinke