Hand crank

System rehabihty is improved by providing alternative means for performing the same task. For example, automobiles were equipped with hand cranks even though they had electric starters. This back-up equipment was provided because at that time starters were unrehable. In contemporary system design, factors such as added cost, weight, and space may prohibit the use of redundant systems. 

Fully automatic processing was introduced in 1972 with the SX-70 camera, which ejected each integral picture unit automatically, passing it between motorized processing rollers and out of the camera immediately after exposure (12,13). Kodak instant cameras, introduced in 1976 and now discontinued, included both motorized and hand-cranked models. Fuji instant cameras for integral films are motorized. 

Kodak instant cameras included battery-operated motorized and lower cost hand-cranked models. The pictures began to develop as they were ejected from the camera, and development proceeded over several minutes under ambient conditions. The films were balanced for daylight exposure. 

Automatic filters are made with either viscous-coated or dry filter media. However, the cleaning or disposal of the loaded medium is essentially continuous and automatic. In most such devices the air passes horizontally through a movable filter curtain. As the filter loads with dust, the curtain is continuously or intermittently advanced to expose clean media to the air flow and to clean or dispose of the loaded medium. Movement of the curtain can be provided by a hand crank or a motor drive. Movement of a motor-driven curtain can be actuated automatically by a differential-pressure switch connected across the filter. 

Archimedes mechanical skill, together with his theoretical knowledge, enabled him to construct many ingenious machines. During his time in Egypt, he invented a hand-cranked manual pump, known as Archimedes screw, that is still used in many parts of the world. Its open structure is capable of lifting fluids even if they contain large amounts of debris. 

The popularity of EVs did not last. By the 1920s, the performance of ICE vehicles improved dramatically, and the earlier major drawbacks had been solved. Ironically, the replacement of the dangerous hand crank -with a battei y-powered electric starter was a major innovation accelerating ICE vehicle sales at the expense of EV sales. At the same time, there were no concurrent solutions to the limitations of battery technology for EVs that addressed the demand to drive faster and farther. 

Propellers for the marine environment appeared first in the eighteenth centui y. The French mathematician and founder of hydrodynamics, Daniel Bernoulli, proposed steam propulsion with screw propellers as early as 1752. However, the first application of the marine propeller was the hand-cranked screw on American inventor David Bushnell s submarine, Turtle in 1776. Also, many experimenters, such as steamboat inventor Robert Fulton, incorporated marine propellers into their designs. 

Direct Indicating Viscometer. This is a rotational type instrument powered by an electric motor or by a hand crank. Mud is contained in the annular space between two cylinders. The outer cylinder or rotor sleeve is driven at a constant rotational velocity its rotation in the mud produces a torque on the inner cylinder or bob. A torsion spring restrains the movement. A dial attached to the bob indicates its displacement. Instrument constants have been so adjusted that plastic viscosity, apparent viscosity, and yield point are obtained by using readings from rotor sleeve speeds of 300 and 600 rpm. 

Radio (preterabiy at ieast one hand crank radio or radio with tresh batteries) ... 

Hand dusters may consist of a sqneeze bnlb, bellows, tube, shaker, sliding tube, or a fan powered by a hand crank. 

The engine was started in the normal way by hand cranking, with the air intake valve fully open and the producer gas valve fully closed. Thus the engine was run on diesel fuel alone at the start. 

Kava preparation today in bars on Pohnpei, and also in Port Vila s nakamals — which feature green kava - relies on various sorts of mechanical grinders, some hand-cranked... 

The hand-cranked freezer with a dasher (paddle) was invented by Nancy Johnson of the U.S. in 1846. This made it possible for everyone to make ice cream. The dasher beat air into it which gave it a better texture and then acted as an insulator, so the ice cream did not appear to be as cold as it was. 

Another modular system is often called laboratory equipment it can be used for small scale production and for the laboratory evaluation of small samples. Fig. 11.26 depicts the design and some of the accessories. In the most simple execution a hopper feeds a pair of rollers which are driven by a hand crank. The rollers can be solid and may be equipped with compacting or briquetting surfaces (see Section 8.4.3) or two perforated, geared, intermeshing pelleting rolls (see Section 8.4.2) are installed to accomplish medium pressure extrusion. In a modular fashion the rollers can be motorized, screw feeders can be added, and the rolls may be oriented vertical or horizontal or in any other direction. As shown in the photographs of Fig. 11.27 the roller frame can be totally enclosed for dust control if toxic or hazardous materials are processed. A panel includes controls and instrumentation for data display and collection. 

FIGURE 66.5 The gross efficiency for hand cranking or bicycling is a function of the rate of work. (From Goldman, R.F., 1978. Computer models in manual materials handling. In Drury, C.G. (Ed), Safety in Manual Materials Handling, National Institute for Occupational Safety and Health (NIOSH), Cincinnati, Ohio, pp. 110-116.)... 

Belt drives use adjustable sheaves. The axial distance between the sheaves can be varied this changes the effective pitch at which the belt contacts the sheave. This, in turn, changes the transmission ratio. The speed is usually varied by a vernier screw mechanism, which is hand cranked or activated electrically. Belt drives are used up to 100 hp. The largest speed ratio is about 10 1, and a maximum speed is typically 4000 rpm. Belt drives have a reasonable efficiency, tolerate shock leads, and provide optimum smoothness in a mechanical drive. Disadvantages are heat generation, possibility of slippage, and relatively poor speed control. In addition, belt drives are subject to wear and, thus, are maintenance-intensive belts generally have to be replaced every 2000 hours. 

In 1864, during the American Civil War, the Confederate submarine CSS Hunley, a 40-foot-long submarine powered by a hand crank turned by its eight-man crew, became the first submarine to destroy an enemy warship when it sank the USS Housalonic off the coast of South Carolina. Although it completed its mission successfully, the Hunky sank, killing its entire crew. 

Machine gun (Richard Gatling) Gatling develops the first machine gun, called the Gatling gun. It has six barrels that rotate into place as the operator turns a hand crank the shells were automatically chambered and fired. 

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