A pawl is a latch that will allow movement in one direction, but prevents return motion. Commonly used in combination with a ratchet wheel.
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It is named after Willam Davies, who was hanged at this location in 1689. The Wheatsheaf is a Grade II listed pub to the southeast of the town, designed in a distinctive ratchet-wheel design.
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Since the 1870s, in an improved version the pendulum drove a ratchet wheel via a pawl on the pendulum rod, and the ratchet wheel drove the rest of the clock train to indicate the time. The pendulum was not impelled on every swing or even at a set interval of time. It was only impelled when its arc of swing had decayed below a certain level. As well as the counting pawl, the pendulum carried a small vane, known as a Hipp's toggle, pivoted at the top, which was completely free to swing.
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The Wheatsheaf is a grade II listed public house in Heatherside, Camberley, Surrey. It was designed by John and Sylvia Reid and opened in 1970. It has a distinctive ratchet-wheel design and connects to the local shopping precinct.
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Until about 1850, the watchmaker’s ébauche consisted of two plates with pillars and bars, the barrel, fusée, index, pawl and ratchet- wheel, along with a few assembling screws. These parts were all roughly filed and milled. The steel and brass were manufactured in a special workshop. The ébauche was finished by watchmakers in a finishing shop.
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Sound waves entering a mouthpiece and falling on a diaphragm were conveyed by a piece of rubber tubing and a spring to a pawl, which vibrated against a very fine-toothed ratchet wheel. The diaphragm and mouthpiece were similar to those used on the phonograph. Vibrations caused by the voice caused a shaft and flywheel to rotate."Edison's Phonomotor," Scientific American, July 27, 1878, page 51.
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The master clock has a conventional self-winding clock mechanism that is rewound electrically. The slave clock mechanism is not a conventional clock mechanism as it consists only of a ratchet wheel and time train. Slave clocks rely upon electrical impulses from the master clock to mechanically move the clock hands one unit of time. Synchronized time systems are made up of one master clock and any number of slave clocks.
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The principle of any power reserve device is that when the mainspring is wound either automatically or manually, a special train of gears connected to the ratchet wheel or the barrel arbor drives the power reserve indication showing the extent of the wind. The barrel’s teeth are also connected to the other side of this differential train so that as the mainspring's power is used, the power reserve indication moves in the opposite direction.
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Even tension is essential as any variation will lead to broken threads. As the warp beam empties its effective diameter changes making the warp slacker- tension is maintained by adding a wooden pulley to the beam, around which are two turns of rope that are attached to mill weights- thus retarding the beam through friction. The cloth beam bears a toothed wheel which works a pinion. A ratchet wheel is attached with a click level to take up the slack in the cloth.
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The pub was designed by the Reids in response to changing social changes following World War II, where segregated bars in pubs were becoming rejected and unfashionable. It has a distinctive ratchet-wheel design covering a single-space bar area, and connects to the local shopping precinct. The interior features various triangular segments called "snugs" or "lounges" overlooking a central circular seating area with a central chimney. It was redesigned in 1989 to include additional space and a function room in what was previously a storage area.
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Gas handgun magazines usually contain 10 to 30 pellets in a standard capacity magazine; however, some are high capacity magazines and can hold 50 rounds or more. In the case of AEG rifles, magazines come in either real- capacity (equivalent to the capacity of its real steel counterpart), low- capacity (10-50 rounds), mid-capacity (75-160 rounds), or high-capacity (190+ rounds). These magazines are spring-loaded. The high-cap magazines often have a ratchet wheel that can be wound up periodically to force pellets up from the holding chamber of the magazine to the feeding chute.
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A separate set of gears called the keyless work winds the mainspring when the crown is rotated, and when the crown is pulled out a short distance allow the hands to be turned to set the watch. The stem attached to the crown has a gear called the clutch or castle wheel, with two rings of teeth that project axially from the ends. When the stem is pushed in, the outer teeth turn the ratchet wheel on top of the mainspring barrel, which turns the shaft that the inner end of the mainspring is attached to, winding the mainspring tighter around the shaft. A spring-loaded pawl or click presses against the ratchet teeth, preventing the mainspring from unwinding.
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The tendency of the pallets to move out of the path of the wheel has some serious consequences. The first is that any time that the drive to the escape wheel is interrupted the pallets lose contact and when the drive is restored, the escape wheel may not be restrained and may accelerate rapidly and uncontrollably. To prevent this happening while the clock was being wound, Harrison invented one of his longest-lasting mechanisms, a maintaining power which is still widely used in clocks and watches. In its usual construction this consists of a ratchet wheel sandwiched between, and co-axial with, the first (and slowest-turning) driving gear of the movement and the barrel that the weight (or spring) is attached to.
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Part of the mechanism includes a 60-tooth ratchet wheel advanced on every pendulum swing by a pawl driven by the electromagnet. Originally this operated a pair of contacts by two pins on its periphery to generate the half-minute pulses, but at some stage these contacts were removed. To the left of the pendulum is the regulator. This is arranged to apply a small force to the pendulum which through an ingenious linkage effectively works against gravity, slowing the pendulum down. The force comes from a torque generated by a spiral hair-spring, one end being attached to the pivot of a lever that forms part of the escapement linkage, the other to a disk that can be rotated in small steps by a solenoid-operated “stepper motor”.
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