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 t ...

and can also be considered a type of

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

. It typically consists of a

spring-loaded A spring is an elastic object that stores mechanical energy. In everyday use the term often refers to coil springs, but there are many different spring designs. Modern springs are typically manufactured from spring steel, although some non ...

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 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, metonomic name for a socket wrench incorporating a ratcheting device * Ratchet (instrument), a music instrument and a ...

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 mos ...

es, bicycle

freehub A freehub is a type of bicycle hub that incorporates a ratcheting mechanism. A set of sprockets (called a " cassette") is mounted onto a splined shaft of the freehub to engage the chain. The ratcheting mechanism is a part of the hub, in contra ...

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 of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a spool (or drum) attache ...

es, and many other applications. ;Ladder:

Dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

s (in the form of pawls) are used on

extension ladder A ladder is a vertical or inclined set of rungs or steps 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 ladders, such a ...

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 arbor, that is driven by an electric motor (either directly, by belt, or by gears). The blade protrudes t ...

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 column ...

is a device in an automobile

automatic transmission An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed transmission used in internal combustion engine-based motor vehicles that does not require any input from the driver to change forward gears under normal driving c ...

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 (also called a wheel gun) is a repeating handgun that has at least one barrel and uses a revolving cylinder containing multiple chambers (each holding a single cartridge) for firing. Because most revolver models hold up to six roun ...

s: The hand (pawl) indexes the

cylinder A cylinder (from ) 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 infin ...

References

{{reflist Mechanisms (engineering) Fasteners de:Sperrklinke