Rack and pinion

FIG. 21-24 a) Rack-and-pinion gate, (h) Double-quadrant gate. 

There are three main classes of spur gears external tooth, internal tooth, and rack-and-pinion. The external tooth variety shown in Figure 39.1 is the most common. Figure 39.2 illustrates an internal gear and Figure 39.3 shows a rack or straight-line spur gear. 

Global Electric Motor s two-seat GEM car is a NEV, with a top speed of 25 mph and a curb weight of 1100 pounds with batteries. A 72-volt shunt GE motor is used with front wheel drive. Six 12-volt deep-cycle batteries are used with hydraulic brakes, independent front wheel suspension, rack and pinion steering, aluminum welded space frame and composite and thermoplastic body. It seats two or four with a price of 7,000 to 9,000. 

Airbag covers, armrests, upholstery... Rack and pinion boots. .. 

Constant velocity joint (CVJ) boots, rack and pinion bellows... 

Duboscq s Colorimeter.—This consists (Fig. 52) of two glass vessels into each of which a glass cylinder may be lowered by means of a rack and pinion. Light reflected from a mirror underneath passes along the axes of the two vessels and cylinders into a system of two prisms, by means of which the two halves of the field of the eye-piece at the top are illuminated. 

In a recent experiment, translational and rotational motion of a single molecule was driven and monitored by the STM tip at 7 K in a sort of rack-and-pinion device.67 The pinion consists of a 1.8 nm diameter molecule acting as a six-toothed wheel interlocked at the edge of a self-assembled molecular island functioning as a rack. The rotation of the pinion molecule tooth by tooth along the rack could be monitored owing to the presence of a chemical tag attached to one of its cogs. 

Hardesty and Ross made careful studies of the pressure to which fertilizer granules could be subjected without degradation. They described a simple device for determining the force necessary to crush individual particles consisting of a rack and pinion similar to that used in adjusting the elevation of a microscope. Below the rack, and resting on a sensitive scale or balance, is a small anvil. The particle is placed on a container in the anvil directly below the rack, the latter being turned down so as to rest on the particle. The pinion is turned until the particle breaks, at which time the maximum deflection of the scale pointer is observed. In this type of experiment it is important that the particles... 

A pair of rigid stainless-steel wire hook-like electrodes with a distance of 4 mm are adjusted to the artery by means of a rack and pinion gear manipulator. The artery is raised slightly away from the surrounding tissue. Isolation of the electrodes is achieved by the insertion of a small piece of parafilm under the artery. Blood flow is measured with an ultrasonic Doppler flowmeter (Transonic, Ithaca NY, USA) the flow probe (1RB) is placed proximal to the damaged area. 

The body tube, a cylinder which holds the draw tube and lenses and moves up and down perpendicularly above the opening in the stage. The tube is raised or lowered either by sliding it back and forth with a twisting movement or by a rack and pinion mechanism. The latter is called the coarse adjustment. 

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