GB558395A - Improvements in or relating to ship's or boat's propellers - Google Patents

Abstract

558,395. Rotary propellers. MORRIS, C. V. June 30, 1942, No. 9037. [Classes 4 and 114] A wholly immersed feathering propeller for boats is mounted on a vertical shaft and can be raised and lowered so as to project below, or be drawn up into a casing above, the level of the boat bottom while in operation. Two such propellers 3, Fig. 1 are vertically adjustable within casings 1 on a flat-bottomed barge and their shafts are driven by bevel gearing in casings 4 from a transverse shaft in a casing 5 driven from a longitudinal shaft having a telescopic and flexible joint near the engine. Each propeller unit comprises a paddle box 7, Fig. 2, slidable within the casing 1 and prevented from rotating therein by a spline 6. A torque-tube 2 connects the box 7 to the casing 4 and encloses the propeller shaft 10 which is keyed to a horizontal plate 12 at its lower end. The plate has apertures in which are pivoted arms 15 carrying blades at their lower ends and rollers 16 at their upper ends to engage cam tracks 17 on the paddle box for feathering the blades. When the blade is in the operative position a guide 18 holds the roller 16 in contact with the cam track. The two casings 4 are connected by a bridge piece 29 having a post 30 sliding through a second bridge piece 31 spanning the casings 1. A lever 34, Fig. 9 is connected to two cables attached to the two bridge pieces and passing respectively over' a pulley 38 on the bridge piece 31 and a pulley 32 on the lower end of the pillar. The speed of the vessel may be controlled by varying the depth of immersion of the paddles by means of the lever 34. Fig. 4 shows a plate 12 apertured for three paddles pivoted about trunnions 22. The arms 15 of the paddles are bent at the pivot to cause the rollers 16 to trail over the cam surface.