Rotary Engine Mountings.
Fig. 117.—Rotary engine mounting, in which engine is supported between two plates.
The mountings associated with the rotary type of engine fall under two categories: those where the motor is supported between two or more plates, and those in which the motor itself is overhung. The method of mounting adopted for the first case is generally the type shown by [Fig. 117]. The plates are pressed or bent up from sheet steel, and all edges flanged to prevent buckling. The front plate embodies a ball race, through which the propeller shaft runs, while to the rear bearer is bolted the back plate of the engine. This arrangement with minor variations has been extensively used for the different makes of small scouting biplanes engined with the 80 h.p. and 100 h.p. Gnome motors.
Where the weight of the rotary engine used is excessive, as in the case of the 160 h.p. Gnome with 20 cylinders, which is now out of date, a mounting incorporating three bearers is used. The arrangement would be similar to that indicated by [Fig. 117], with the addition of an extra bearer for the support of the crank-shaft extension.