Patent GB-353316-A (GB)
Title: Vertical-lift aeroplane
IPC: B64C23/00
Filed: 1930-09-18
Abstract: 353,316. Supporting and controlling aircraft ; screw propellers. WINDSOR, G. W., 2538, Burnett Way, and GRIMM, A. E., 2981, 35th Street, both in Sacramento, California, U.S.A. Sept. 18, 1930, No. 27964. [Classes 4 and 114.] An aeroplane is provided with three lifting propellers disposed in holes in the wings near the tips and in a hole through the rear part of the fuselage and relatively variable in speed irrespective of the speed of the prime mover. The propellers at the wing tips also are tiltable to enable them to be used for forward propulsion, the rear propeller being stopped. Alternatively the wing tip propellers may be variable in pitch instead of speed. The wing tip propellers are mounted in loop-shaped frames pivoted on transverse axes in openings in the wings and provided with sprockets enabling them to be tilted by chain gear from a parallel shaft extending into the fuselage. The propellers are driven by bevel gear from two shafts 10, Fig. 5, extending through the pivots of the frames to two splined shafts 10a having sliding wheels 17 in frictional contact with a driving disc 18 driven from the main engine through chain gear and bevel drive 20. The disc 18 is mounted on a splined shaft 46 and pressed into contact with the wheels 17 by a spring 47. The wheels 17 are moved to vary the speed of the shafts 10 by forks 27, mounted on sleeves 28 sliding in bearings 29, the sleeves being connected by links 35 to the front and rear ends of a longitudinal plate 32 engaging a squared portion of a universally pivoted lever 30 so that lateral tilting movements of the lever vary the speeds of the shafts differentially and rotary movements of the lever vary the speeds equally in the same direction. The plate 32 is supported in a loop 33 with a fore and aft slot carried by rods 34 sliding without rotation in the sleeves 28. The rear propeller is mounted in a similar frame but is fixed in the fuselage and its driving shaft has a disc 37, Figs. 5 and 6, contacting with the disc 18 but mounted in an eccentric bearing 43 which can be turned to move the disc 37 out of contact with the disc 18 to stop the rear propeller. The disc 37 can be slid along the splined end of the shaft by a fork 38 on a rod 39 sliding in a bearing 40, the forward end of the rod having a transverse loop 41 engaging the rod 30 so that fore and aft movements of the rod 30 vary the speed of the rear propeller. The main engine drives the disc 18 through a clutch controlled by the pilot and another clutch enables the engine to drive a tractor propeller. Fig. 9 shows a variable pitch propeller for use at the wing tips, the blades having spindles 52 pivoted in the hub and having oppositely inclined cranks 56 connected by links 55 to a block 54 sliding on the hub spindle. A rod 57 passing through the spindle is moved by a bell crank 58 connected to a rod 59 passing through the pivotal axis of the tilting frame to a bell crank 60. The bell crank 60 may be operated by mechanism similar to that described for varying the speed of the propellers and in this case a simple drive may be substituted for the variable speed drive.