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Pawl
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 and can also be considered a type of dog. It typically consists of a spring-loaded 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 gear in socket wrenches, bicycle freehubs, winches, ratchet reels for diving, fishing, and many other applications. ;Ladder: Dogs (in the form of pawls) are used on extension ladders to temporarily anchor their sections to one-another. ;Table saw: Pawls are used on table saws to prevent a workpiece being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 shift, frontmost on a floor shift) in all cars sold in the United States since 1965 (when the order was standardised by the ''Society of Automotive Engineers'' (SAE)) through ''SAE J915'', and in most other vehicles worldwide. Mechanism The parking pawl locks the transmission's ''output shaft'' to the transmission casing by engaging a ''pawl'' (a pin) that engages in a notched wheel on the shaft, stopping it (and thus the driven wheels) from rotating. The main components of a parking pawl mechanism are the parking gear, parking pawl, actuator rod, cam collar, cam plate, pivot pin, and parking pawl return spring. The mechanism assembly is designed so that the parking pawl tooth collides and overrides the parking gear teeth (ratchets) un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratchet (device)
A ratchet (occasionally spelled rachet) is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. The word ''ratchet'' is also used informally to refer to a ratcheting socket wrench. __TOC__ Theory of operation A ratchet consists of a round gear or a linear rack with teeth, and a pivoting, spring-loaded finger called a '' pawl'' (or ''click'', in clocks and watches) that engages the teeth. The teeth are uniform but are usually asymmetrical, with each tooth having a moderate slope on one edge and a much steeper slope on the other edge. When the teeth are moving in the unrestricted (i.e. forward) direction, the pawl easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (often with an audible 'click') into the depression between the teeth as it passes the tip of each tooth. When the teeth move in the oppo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pawl Brake (English)
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 and can also be considered a type of dog. It typically consists of a spring-loaded 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 gear in socket wrenches, bicycle freehubs, winches, ratchet reels for diving, fishing, and many other applications. ;Ladder: Dogs (in the form of pawls) are used on extension ladders to temporarily anchor their sections to one-another. ;Table saw: Pawls are used on table saws to prevent a workpiece being saw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishing Reel
A fishing reel is a hand-crank (mechanism), cranked reel used in angling to wind and stow fishing line, typically mounted onto a fishing rod, but may also be used on compound bows or crossbows to retrieve tethered arrows when bowfishing. Modern recreational fishing reels usually have fittings aiding in casting (fishing), casting for distance and accuracy, as well as controlling the speed and tension of line retrieval to avoid line snap and fishing hook, hook dislodgement. Fishing reels are traditionally used for bass fishing in angling and fly casting, competitive casting. They are typically attached near the handle of a fishing rod, though some specialized reels with pressure sensors for immediate retrieval are equipped on downrigger systems which are mounted directly to an ocean-going sport boat's gunwales or transom (nautical), transoms and are used for "deep drop" and trolling (fishing), trolling. The earliest fishing reel was invented in China at least since the Song dynasty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 mechanism is mounted below a table that provides support for the material, usually wood, being cut, with the blade protruding up through the table into the material. In most modern table saws, the table is fixed and the blade position can be adjusted. Moving the blade up or down affects the depth of the cut by controlling how much of the blade is protruding above the table surface. Many saws also have an adjustable angle, where the blade can be tilted relative to the table. Some earlier saws instead had a fixed blade and the table could be adjusted for height (exposure of blade) and angle relative to the blade. Types The general types of table saws are compact, benchtop, jobsite, contractor, hybrid, cabinet, and sliding table saws. Bench ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 that restrains and manipulates the anchor chain on a boat, allowing the anchor to be raised and lowered by means of chain cable. A notched wheel engages the links of the chain or the rope. A trawl windlass is a similar machine that restrains or manipulates the trawl on a commercial fishing vessel. The trawl is a sort of big fishing net that is wound on the windlass. The fishermen either let-out the trawl or heave-up the trawl during fishing operations. A brake is provided for additional control. The windlass is usually powered by an electric or hydraulic motor operating via a gear train. Horizontal or vertical Technically speaking, the term "windlass" refers only to horizontal winches. Vertical designs are correctly called capstans. Horizo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dog (engineering)
In engineering, a dog is a tool or part of a tool, such as a pawl, that prevents or imparts movement through physical engagement. It may hold another object in place by blocking it, clamping it, or otherwise obstructing its movement. Or it may couple various parts together so that they move in unison – the primary example of this being a flexible drive to mate two shafts in order to transmit torque. Some devices use dog clutches to lock together two spinning components. In a manual transmission, the dog clutches, or "dogs" lock the selected gear to the shaft it rotates on. Unless the dog is engaged, the gear will simply freewheel on the shaft. This word usage is a metaphor derived from the idea of a dog (animal) biting and holding on, the "dog" name derived from the basic idea of how a dog jaw locks on, by the movement of the jaw, or by the presence of many teeth. In engineering the "dog" device has some special engineering work when making it – it is not a simple part to make ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ladders, such as those made of rope or aluminium, that may be hung from the top. The vertical members of a rigid ladder are called stringers or rails (US) or stiles (UK). Rigid ladders are usually portable, but some types are permanently fixed to a structure, building, or equipment. They are commonly made of metal, wood, or fiberglass, but they have been known to be made of tough plastic. Historical usages Ladders are ancient tools and technology. A ladder is featured in a Mesolithic rock painting that is at least 10,000 years old, depicted in the Spider Caves in Valencia, Spain. The painting depicts two humans using a ladder to reach a wild honeybee nest to harvest honey. The ladder is depicted as long and flexible, possibly made out of som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Bobbin, spool (or drum) attached to a hand crank (mechanism), crank. Traditionally, winches on ships accumulated wire or rope on the drum; those that do not accumulate, and instead pass on the wire/rope (see yacht photo above), are called Capstan_(nautical), capstans. Despite this, sailboat capstans are most often referred to as winches. Winches are the basis of such machines as tow trucks, steam shovels and elevators. More complex designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. It might include a solenoid brake and/or a Mechanical brake stretch wrapper, mechanical brake or ratchet (device), ratchet and pawl which prevents it unwinding unless the pawl is retracted. The rope may b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 prevalent form is the ratcheting socket wrench, often informally called a ratchet. A ratchet incorporates a reversible ratcheting mechanism which allows the user to pivot the tool back and forth to turn its socket instead of removing and repositioning a wrench to do so. Other common methods of driving sockets include pneumatic impact wrenches, hydraulic torque wrenches, torque multipliers and breaker bars. Some lesser known hybrid drivers include striking wrench tools with square drive, and hydraulic impact wrenches (typically powered by on site hydraulic power such as present with military tanks, and many rail car applications). Interchangeable sockets The basic contemporary form of socket is hexagonal, referred to as "6-point" for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratchet Reel (diving)
A distance line, penetration line, cave line, wreck line or guide line is an item of diving equipment used by scuba divers as a means of returning to a safe starting point in conditions of low visibility, water currents or where pilotage is difficult. They are often used in cave diving and wreck diving where the diver must return to open water after a penetration when it may be difficult to discern the return route. Guide lines are also useful in the event of silt out. Distance lines are wound on to a spool or a reel for storage, and are laid ''in situ'' by unrolling. The length of the distance line used is dependent on the plan for the dive. An open water diver using the distance line only for a surface marker buoy may only need , whereas a cave diver may use multiple reels of lengths from to 1000+ ft (300 m). Reels for distance lines may have a locking mechanism, ratchet or adjustable drag to control deployment of the line and a winding handle to help keep slack l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
