Abstract: A corrosion preventing device is disclosed for mounting in sea water on an electrically conductive propeller shaft supporting a marine propeller composed of a metal having a first galvanic potential. The propeller is fastened to the shaft by an electrically conductive propeller nut and is in electrical contact therewith. The device includes an annular washer having a generally circular periphery, composed of a metal having a second galvanic potential not greater than the first galvanic potential, with a central hole concentric with the circular axis thereof through which the shaft may fit to enable an electrical conductive mounting proximate to the propeller nut, for serving as an electrolytic cathode of the device.

Abstract: A durable shroud is provided for roof ventilators to prevent warm air from escaping through ventilators openings as well as to provide a protective cover for the ventilator in inclement weather. The ventilator is comprised of two hemispherical segments that are coupled to form a complete hemisphere about a roof ventilator. Therefore, weather elements are prevented from contacting the ventilator and heat from within is prevented from escaping through the ventilator openings.

Abstract: A sacrificial anodic protector kit for propeller shafts comprising a split zinc collar having a copper layer on its interior surface. The collar is clampable about a propeller shaft by machine screws mateable with nuts embedded in the collar.

Abstract: An above-rotor mount (30) for a helicopter (10) comprises an upper plate (32) coupled to a lower plate (34) by means of links (42, 44, 46 and 48). The lower plate (34) is connected to a rotating rotor shaft (16) and a non-rotating stand pipe (40) extending inside the rotor shaft. The links (42, 44, 46 and 48) are focused to control the mode shapes and dynamic response of the mounted components at a preselected frequency, such as the predominant rotor harmonic. Springs (50, 52) are connected between the plates (32, 34) for damping.

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gear case having a hollow interior and having at the rearward end thereof an inwardly extending inner circular surface defining an opening through which exhaust gases and engine cooling water are discharged from the lower unit, and a propeller shaft rotatably journaled in the gear case and including a portion extending rearwardly of the gear case. A propeller including a hub is mounted on the propeller shaft rearward portion for common rotation of the hub with the propeller shaft. The propeller also includes a forward portion adjacent the rearward end of the gear case, and a propeller blade extending radially outwardly from the hub.

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gear case including a hollow interior having at the rearward end thereof an inwardly extending inner circular surface defining an opening through which exhaust gases and engine cooling water are discharged from the lower unit, a propeller shaft rotatably journalled in the gear case and including a portion extending rearwardly of the gear case, a propeller including an inner part mounted on the propeller shaft rearward portion for common rotation of the inner part with the propeller shaft, an outer part having an outer circular surface with a diameter materially less than the diameter of the inner circular surface of the gear case, a blade extending radially outwardly from the outer part, and a resilient cushion connecting the inner and outer parts, and a thrust washer carried by the propeller shaft in forward thrust transmitting engagement therewith and in forward thrust receiving engagement with the propeller outer part, and a

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gear case including a hollow interior having at the rearward end thereof an inwardly extending inner circular surface defining an opening through which exhaust gases and engine cooling water are discharged from the lower unit, a propeller shaft rotatably journalled in the gear case and including a portion extending rearwardly of the gear case, a propeller including an inner part mounted on the propeller shaft rearward portion for common rotation of the inner part with the propeller shaft, an outer part having an outer circular surface with a diameter materially less than the diameter of the inner circular surface of the gear case, a blade extending radially outwardly from the outer part, and a resilient cushion connecting the inner and outer parts, and a thrust washer carried by the propeller shaft in forward thrust transmitting engagement therewith and in forward thrust receiving engagement with the propeller outer part, and a

Abstract: This anti-theft device has a plurality of arcuate metallic sections hingedly connected to be removably applied to an airplane propeller blade at one side of the propeller shaft and locked in place to prevent unauthorized removal. The device forms an eccentric weight mass which when the engine is operated, causes vibrations so severe that the aircraft cannot take off or fly successfully. A warning flag or banner is attached to the device and anyone at all familiar with aircraft operation will not attempt to take the plane.

Abstract: A propeller having a specified combination of blade sweep, camber and rake which provides distinct operating advantages when utilized on pleasure boats; and further including weed cutting and protection features which make the prop particularly suitable for use on outboard motors and stern drives employing underwater exhaust through the lower gear case housing. Propeller blade rake and camber are adjusted as described to improve performance of light to moderately loaded, medium to high speed pleasure boats. The blades are swept aft and weed cutting blade-like fingers extend forwardly of the propeller blades to prevent weeds from accumulating forward of the prop and blocking the exhaust passageway.

Abstract: Apparatus for facilitating dismounting and remounting a removable blade of a shrouded marine propeller comprises detachable brackets that are temporarily affixed to the propeller hub and the blade to be removed and a pivot pin that is installed through aligned holes in the brackets and forms a pivot axis about which the blade is flipped back out of the shroud, the blade having previously been positioned to reside generally in a plane including the propeller hub axis.

Abstract: For use with a marine propeller which is mounted on an output shaft of a power source, a marine propeller lock comprising a fastener on the shaft for preventing axial movement of the propeller on said shaft and a cover member having a portion thereof engaging the end of the shaft and another portion thereof surrounding the fastener on the output shaft. The fastener has an opening in the end thereof projecting beyond the end of the shaft and the cover engages the shaft and has an opening therein aligned with the opening in the fastener. A lock is insertable through the opening in the cover into the opening in the fastener and has interengaging means thereon engaging the fastener to hold said cover in position and thereby prevent access to said fastener.

Abstract: A propeller lock system comprised of an inner fin lock and an outer fin lock, with the outer fin lock adapted to lock to the inner fin lock to prevent removal from its locking position on a propeller housing.