THIS description of the hydraulic control used with the hydra-matic transmission reveals how the control operates to change ratios under power without direction from the driver. The control's pattern of automatic shifting for ordinary, high-range driving has been selected as the best compromise between top performance and low ratio of engine noise to wind noise. The control's low range shifts gears according to performance dictates alone, furnishing greater power for extreme conditions at low speeds and enabling the driver to use his engine as a brake on steep descents. Heart of the control system is a double hydraulic governor, sensitive both to car speed and throttle opening. THIS paper, as well as the two that follow, one by Messrs. Nutt and Smirl and the other by Mr. Kimberly, make up a symposium on automatic transmission components presented at the 1947 SAE Summer Meeting.
N O-ring seal is a synthetic-rubber torus fitting in a groove in the piston surface and sealing against the cylinder wall of an hydraulic mechanism. O-ring seals have been found to be effective, dependable, and economical for both static and moving seal applications. If molded of super synthetic rubbers, they may be successfully used with fluid pressures up to 3000 psi.
A NEW electronic circuit arrangement added to the electro-optical pyrometer developed at the University of Wisconsin indicates instantaneously the temperature in the combustion chamber of a diesel engine. The electronic device, which is described in this paper, solves an equation relating true temperature to intensity and wave length of monochromatic radiation from a luminous flame. True flame temperature is charted on an oscillograph as a function of such abscissas as time or crank angle. Several circuits are reviewed which were found unsuited for use with the pyrometer but which may be useful for other applications.
THE engine analyzer described here utilizes the cathode ray tube and specially adapted circuits in a graphical indicator located at the flight engineer's station. It is designed as a permanently installed instrument for aircraft carrying a flight engineer or as plug-in test equipment for smaller planes. The analyzer is claimed to: 1. Increase aircraft utilization through the reduction of service time and expense. 2. Increase safety through knowing the conditions of engine operation, so that imminent failures can be anticipated during flight. 3. Increase knowledge about actual engine behavior during flight, so that more efficient operating methods can be used.
OPERATING characteristics of several propeller-engine combinations for private-owner type aircraft are reviewed to compare performance, weight, and cost. It is concluded that, for airplanes having low wing loading and high power loading, controllable-pitch propellers improve take-off and climb performance. However, weight and cost considerations favor the simpler automatic 2-position propellers. Planes with high wing loading and low power loading definitely need controllable-pitch propellers.
PROPER protection of metal parts operating as bearing surfaces, or in contact under relatively heavy loads, during the break-in period often means the difference between successful operation and failure. Various surface coatings have been investigated to discover which ones will give this protection. The authors discuss here three types of surface treatment for cast-iron and steel that do give superior wear and scuff resistance.