Abstract: A turbine installation having reduced inner and outer gaps comprises a water passageway and a turbine runner disposed in the passageway downstream of a discharge ring. The turbine runner includes a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis and a plurality of runner blades. Each blade comprises a hydrofoil having an inner edge and a distal outer edge, a leading edge and a trailing edge separated by a water directing surface. Each blade is pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis so that its inner edge is proximate the hub. Each blade is rotatable between a maximum pitch position and a minimum pitch position. The discharge ring has a spherical configuration cooperable with the outer edge of each of the blades to reduce an outer gap formed between the outer edge of each of the blades and the passageway.

Abstract: An anti-theft device, for preventing unauthorized access to the propeller retaining nut, includes two sections that fit together to form an access-preventing cap. The cap fits around an expanded rim normally found on propeller center-bodies, and the cap cannot be pulled off the propeller center-body without disengaging the two sections from one another. A tongue extending from one section is engaged by a grooved dowel going through the base portion of the second section to hold the two sections together. A key operated locking flap engages the groove in the dowel to prevent removal of the dowel without possession of the appropriate key. In a second embodiment, an adapter is placed on the propeller shaft, between the propeller and the propeller retaining nut. The access-preventing cap is of smaller dimensions than in the first embodiment and is shaped to engage the adapter.

Abstract: A propeller device includes a shaft rotatably supported in a marine engine, and a hub secured to the shaft and having three or more axially extending keys. A propeller housing includes three or more pairs of lobes for forming keyways and for engaging with the keys of the hub. The keyways include a narrower outer end for preventing the housing from disengaging from the hub. Three or more stops are disposed between the pairs of lobes. A retainer disc includes a number of angularly spaced ears for engaging with the lobes and the stops and for preventing the propeller housing from being disengaged from the propeller shaft.

Abstract: A turbine, disposed in water flowing therethrough, includes a hub and associated runner blades. Each blade comprises an inner surface and a distal outer surface, a leading edge and a trailing edge separated by a water directing surface. Each blade is rotatable relative to the hub about a blade rotational axis. The hub includes a spherically-shaped outer surface in a region of the hub swept by the inner surface of the blades when the blades are rotated from maximum to minimum pitch. The hub may also be associated with blades in which the chord is reduced in the root region of the blade. The turbine may also include seals attached to the blade inner surface and an essentially spherically-shaped discharge ring to improve certain turbine parameters such as cavitation, efficiency, flow disturbance, and fish survivability.

Abstract: A turbine, adaptable to improve the survivability of fish present in water flowing therethrough, includes a hub and associated runner blades. Each blade comprises an inner edge and a distal outer edge, a leading edge and a trailing edge separated by a water directing surface. Each blade is rotatable relative to the hub about a blade rotational axis. The turbine is provided with features designed to shield a gap formed between the hub and the blade inner edge as the blade is rotated about its axis.

Abstract: Apparatus is provided for creating heat by electromagnetic induction between relatively rotating components. In RAT applications, part of the nose cone (34) is formed from electrically conductive material (106) which is in thermally conductive relation to the nose cone exterior. A magnetic field is created by components (60) that are spaced apart from the electrically conductive material and relatively rotatable with respect to that material. The electrically conductive material intersects the magnetic field, at least in part, such that eddy currents are created in the electrically conductive material by relative rotation with respect to the magnetic field. These eddy currents create heat which is conducted to the exterior surface of the RAT nose cone. Preferably, the magnetic field is created by a pair of spaced-apart permanent magnets (60) mounted on a support plate (62) inside the RAT hub (28) and immediately behind the nose cone.

Abstract: An auxiliary propelling structure can be attached to an existing propeller system including a propeller having a boss, a propeller shaft and a tightening nut screwed onto the end of the shaft. The auxiliary propelling structure includes an auxiliary boss that is approximately cylindrical to enclose closely the tightening nut of the existing propeller system and having an internal partition with a central through-hole. The partition is pressed against the tightening nut.

Abstract: A motorboat impeller comprises an axial portion having a through axial hole and having a plurality of blades mounted around the periphery thereof and further having a plurality of retaining slots in the inner wall of the through axial hole. The retaining slots have a predetermined depth and a predetermined length extending from the front end of the axial portion toward the inside of the axial portion along the direction of the axis of the axial portion. A mounting and dismounting element can be disposed in the retaining slots and is provided with a body of a polygonal construction and having a plurality of retaining blocks extending outwards. The retaining blocks are dimensioned to fit into the retaining slots. The body of the mounting and dismounting element can be held firmly with a hand tool to facilitate the turning of the axial portion.

Abstract: A motorboat impeller comprises an axial portion, a plurality of blades attached to the periphery of the axial portion, an axial casing, and a nose. The axial portion of a conical construction has a front end with an outer diameter smaller than an outer diameter of a rear end thereof and further has a first axial hole extending therethrough. The axial casing is fastened to the inside of the front end of the first axial hole and is harder in quality than the axial portion. The axial casing is provided therethrough with a second axial hole having in the inner wall thereof a plurality of retaining slots engageable with the splines of a driveshaft. The nose of an elastic material is attached to the front end of the axial portion so that the axial portion has a streamline profile.

Abstract: A water jet propelled boat is equipped with a water intake opening, a water jet outlet, and with a mixed flow type impeller, where the above mentioned water intake opening and the above mentioned water jet outlet are connected by a water passage with the impeller in the middle of the water passage, and where the operation of the impeller causes water to be drawn into the water intake opening and expelled through the above mentioned water outlet to propel the boat. The impeller structure is such that a boss section of the impeller has a plurality fins affixed to it, the outside edges of the above mentioned spiral fins are roughly parallel to the axial center of the above mentioned boss, and, the leading and the trailing edges of the fins, with respect to the axial center of the above described boss, slant down toward the above mentioned water outlet opening. At the same time relative speeds, the invention allows a smaller diameter fin unit and, at speeds of 4,000 rpm and over, it offers improved efficiency.

Abstract: A weed resistant boat propeller is disclosed. The propeller includes a generally circular hub that is adapted for mounting to and being rotatably driven by a boat motor. There are a plurality of blades mounted to a circumferential surface of the hub and extending therefrom in a spiral configuration. Each blade includes a curved leading edge that has an arc dy/dx<1 for the entire length of the leading edge.

Abstract: Pitch adjustment in a feathering propeller employing a planet gear engagement between a pinion hub keyed on the drive shaft and planet pinions at the base of the blades of the propeller which are rotatably mounted through holes of the wall of a hub's casing may be easily performed manually by registering the relative angular position of a second portion of casing in respect to a first portion of the casing housing the planet gear. The registration of the pitch takes place by parting the second portion of casing from the first portion against the resistance of a push-back spring for a distance sufficient to disengage a coupling between the second portion and first portion of the casing or the pinion hub, rotating the second portion so disengaged in respect to the first portion of the casing before releasing the pull causing again the engagement of the two portions in a modified relative angular position.

Abstract: A marine propeller theft deterrent system is designed for use on a conventional propeller assembly. The system comprises an annular ring component which fits onto an end portion of the propeller's drive shaft and abuts against a hub of the propeller assembly. The annular ring component has an annular groove around an outer periphery of its inside face and a set of upstanding cantilevered springs spaced thereon inside of the annular groove. A rounded cover component has an open end dimensioned to fit over the cantilevered springs and an end wall dimensioned to fit into the annular groove of the annular ring component. When properly positioned, the rounded cover component is in locking engagement with the annular ring component. As such, a retaining nut for the propeller hub is concealed and access to it rendered difficult.

Abstract: A waterproof structure for a fan motor comprising a vertical motor shaft projecting from the lower surface of a motor yoke and a fan boss portion which has a bottomed cylindrical shape formed by a bottom opposite to the lower surface of the motor yoke, an outer cylinder opposite to the outer periphery of the motor yoke and which is mounted on the motor shaft at the center thereof. The bottom of the fan boss portion, opposite to the lower surface of the motor yoke is partitioned by concentric circular ribs to form a plurality of enclosed rooms having floors which are successively lower in the direction toward the outer periphery and notches for allowing the adjacent enclosed rooms to communicate with each other are formed in the ribs in such a manner that the notches of the adjacent ribs are offset from one another so as to be placed on different radial lines.

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gear case, a propeller shaft extending in the gear case, an annulus of greater dimension than the propeller shaft and of material weight, and a ring of elastomeric material resiliently connecting the annulus to the propeller shaft is co-axial relation thereto so as to provide for rotation of the annulus in common with rotation of the propeller shaft.

Abstract: Disclosed is a marine propeller for inboard, outboard, or inboard/outboard motors. The propeller is made from a non-metallic composite material that will not deform or deflect even at very high horsepower or RPMs. At the same time, the propeller is substantially less expensive than traditional metallic propellers. An especially unique feature of the propeller is that, unlike metallic propellers, it will shatter when it strikes a solid object in the water, thereby avoiding the engine and drive line damage that occurs when rigid metallic propellers strike a solid object. Also disclosed is a coupling member that permits the propeller to be adapted for use with most inboard/outboard motor configurations.

Abstract: A device for increasing the efficiency of operation of an internal combustion engine used in outboard and inboard/outboard motors comprised of a generally cylindrical member having inner and outer peripheral shell members defining a cylindrical annular space therebetween, wherein are located a plurality of turbine vanes spanning the annular volume between said inner and outer shell members. Said inner and outer shell members and said plurality of vanes are drivingly connected to the propeller shaft of an outboard motor and are mounted coaxially with said propeller shaft. The device is located in the forward end of the inner propeller hub and rotatably mounted in association with the lower unit of said outboard or inboard/outboard motor so that exhaust gases flowing through said lower unit pass through said annular volume. Upon rotation of said propeller shaft, said plurality of vanes are caused to rotate at the same angular velocity thereof.

Abstract: A marine propulsion device including a propeller shaft, a lower unit rotatably supporting the propeller shaft and including a lower unit exhaust passageway, and a propeller adapted to be submerged in water and including an inner hub connected to the propeller shaft. The propeller also includes an outer hub connected to and spaced from the inner hub and defining a propeller exhaust passageway having an inlet in communication with the lower unit exhaust passageway, a plurality of blades extending from the outer hub rearwardly of the inlet, an opening for communicating the lower unit exhaust passageway with water outside of the outer hub, and a member located adjacent and rearward of the opening, and extending forwardly and radially outwardly with respect to the propeller shaft.

Abstract: An anti-theft device for a marine propeller has a spinnerplaced over the propeller nut which secures the propeller to the propeller shaft, and the spinner is held in place against unauthorized removal by a lock pin projecting from the propeller nut into an annular recess in the spinner, enabling the spinner to spin freely relative to the propeller nut while capturing the spinner against axial movement which would expose the propeller nut for unauthorized wrenching, the spinner including a radially extending access passage for gaining access to the lock pin with an authorized drive member to move the lock pin out of the annular recess for selective release of the spinner from the propeller nut and authorized access to the propeller nut for wrenching.

Abstract: A weedless propeller comprising a major hub having a plurality of propeller blades. The rearward end of the major hub is bluntly terminated immediately aft the trailing edge of the blades at the root of the blades. A secondary hub is connected to the forward end of the primary hub. The junction between the forward end of the secondary hub and the shroud of the engine or motor driving the propeller is spaced a substantial distance from the major hub and blades. Preferably, the diameter of the primary and secondary hub is the same, with the diameter of the forward end of the secondary hub being substantially equal to the diameter of the shroud of the motor to create a streamline flow of water along the shroud and along the secondary and primary hubs.

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 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: A self-locking propeller nut, suitable for marine drive trains which involve a great deal of vibration, is disclosed. The nut, which has a nose-cone shaped exterior similar to conventional propeller nuts, is molded integrally of semi-rigid plastic. At its center is a threaded bore wherein the thread diameter tapers narrower into the nut and wherein the thread spacing is slightly different from that of the propeller shaft end. The threaded bore lies in an inner cylindrical body which is recessed and connected to the housing in such a way as to further promote retention of the nut on the shaft.

Abstract: A protector kit for the outboard end of a marine propeller shaft including a reusable brass fastener sandwiched between a sacrificial anodic zinc nose piece and the end of the shaft. The brass fastener serves as a jam nut for the propeller and includes a deformable member and a set screw cooperating with one another to hold a propeller and the nose piece assembled to the shaft. The cup-shaped nose piece is formed solely of zinc and its internal threads hold it securely assembled to the brass fastener by an interference fit between the nose piece threads and the shallow inboard end of the brass fastener threads.

Abstract: A runner hub for a propeller type hydraulic turbine wherein the hub is constructed of at least a pair of arcuate segments. When the arcuate segments are assembled together, they form a hollow hub. Turnbuckles are provided within the hub attached to opposite hub segments and are adjustable to forcibly hold the hub segments in the assembled position.