時間：2011-03-11 23:11來源：藍(lán)天飛行翻譯 作者：admin 點擊：次
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cam engine (reciprocating engine). A reciprocating engine with axial cylinders arranged around a central shaft. Rollers in the open end of the pistons press against a sinusoidal cam mounted on the shaft to rotate the shaft. cam-ground piston (reciprocating engine component). A specially shaped piston used in an aircraft reciprocating engine. The piston is not round, but is ground in such a way that its diameter parallel to the wrist pin is slightly smaller than its diameter perpendicular to the pin. The mass of metal used in the wrist pin boss, the enlarged area around the wrist pin hole, expands when it is heated, and when the piston is at its operating temperature, it has expanded until it is perfectly round. cam lobe. An eccentric used to change rotary motion into linear motion. The valve operating cams used in a reciprocating engine are eccentrics made onto the cam shaft. These eccentrics are enlarged portions of the cam shaft that rotate about a center different from the shaft’s center. The cam followers that operate the valves ride on the cam lobes, and as the cam shaft rotates, the cam lobes move the cam followers up and down in a direction perpendicular to the axis of the cam shaft. cam nose. The peak, or highest point, on a cam. The cam nose is the part of the cam that pushes up on the cam follower. cam pawl. A device that allows a wheel to turn in one direction, but prevents its turning in the opposite direction. The cam pawl, an eccentric that rides over the surface of a wheel, allows the wheel to turn in one direction, but when it tries to turn in the opposite direction, the cam wedges against the wheel and prevents its turning. cam ring (radial engine component). A ring or plate with lobes ground around its periphery. Cam rings are used in radial aircraft engines to push against cam followers and push rods to open the intake and exhaust valves. |
