Abstract:
A locking boat propeller cover that completely encloses the propeller whereby unauthorized removal of the propeller is prevented, the propeller is protected from damage, and the risk of injury to people coming into contact with the propeller area is reduced.

Description:
This invention relates to a locking cover for a marine-type propeller to prevent unauthorized removal of the propeller, to protect the propeller from damage, and to protect individuals from injury due to unintended contact with an uncovered propeller. 
     BACKGROUND OF THE INVENTION 
     Propellers commonly found on outboard and inboard motors of marine vessels are subject to theft and damage when not in use. Some propellers are made of expensive materials designed to defeat corrosion and are consequently more costly and increasingly subject to theft. New innovative propeller designs also tend to increase cost. Propellers are also exposed to damage when the vessel is being trailered, or is sitting out of the water. Small nicks or blemishes in a propeller can substantially reduce efficiency. 
     Propellers also present a risk of injury to people when the vessel is out of the water. Children playing in and around boars may be cut by falling on or running into the blades of the propeller. Adults are also at risk as they may come into contact with the propeller in a manner which can cause injury. 
     Several propeller locking mechanisms are disclosed in the prior art. For example, U.S. Pat. No. 3,732,033 to Macchi discloses a device which prevents access to the nut retaining the propeller. U.S. Pat. No. 4,715,783 to Wade discloses a device which physically prevents removal of the propeller even if the retaining nut is removed. However, the prior art does not disclose a device which both prevents removal of the propeller and encloses the propeller in a cover such that the propeller is protected from damage and theft, and people are protected from injury resulting from unintentional contact with the propeller. 
     It is the principal object of this invention to provide a boat propeller cover which both prevents theft or damage of the propeller and protects people from injury due to unintentional contact with the propeller. Other objects of this invention include the provision of a boat propeller cover which is adaptable to various propeller sizes, durable, easy to manufacture, inexpensive, and easy to operate. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a boat propeller cover embodying the invention. 
     FIG. 2 is a right-side elevational view of a boat propeller cover embodying the invention. 
     FIG. 3 is a front elevational view of a boat propeller cover embodying the invention. 
     FIG. 4 is a rear elevational view of a boat propeller cover embodying the invention. 
     FIG. 5 is a left-side elevational view of a boat propeller cover embodying the invention. 
    
    
     SUMMARY OF THE INVENTION 
     The invention comprises a hinged housing in the general form of a truncated cone. The housing is divided into two generally equal portions, connected at one edge by hinge means. Opposite the hinge is a latching mechanism provided with an eyelet designed to accept a standard padlock. The cover is opened and placed around the propeller and then closed and latched. A padlock may then be used to lock the housing portions together. The latching mechanism provides several openings for receiving an eyelet, such that different sizes of propellers may be accommodated by one size housing. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As best seen in FIG. 1, the invention involves a housing 10 divided into two approximately equal halves 12 and 14. The housing 10, when in use, completely encloses a propeller 40. The housing 10 may be any suitable shape, but is shown in this embodiment as generally a truncated cone. The housing 10 includes a flat front surface 22, and a flat rear surface 24. The flat rear surface 24 surrounds an opening 26 which accommodates the propeller shaft 42. The two halves 12 and 14 are flexibly connected with a hinge 32. The hinge 32 is affixed to the inside of the housing 10 to reduce the likelihood that the hinge 32 may be tampered with by someone attempting to steal the propeller 40. The hinge 32 is attached to a portion 30 of the housing 10 which is of constant diameter to better accommodate the hinge 32. 
     Opposite the hinge is a latch 34. The latch is connected to the inside of the housing 10 by any suitable means. In this embodiment the latch 34 is spot welded to the inside of the housing 10 at latch tabs 35. The latch 34 passes through the housing 10 via opening 37. The connection of the latch 34 to the inside of the housing 10 also enhances resistance to tampering. The latch 34 contains several openings 36 through which padlock eyelet 38 passes. Padlock eyelet 38 is attached through any suitable means to the housing 10 on the housing half not connected to latch 34, and is positioned on portion 30 of the housing 10 which is of constant diameter. As is evident from FIG. 2, the size of the closed housing 10 will depend upon through which opening 36 the padlock eyelet 38 passes. 
     To use the propeller cover, the two housing halves 12 and 14 are spread apart about hinge 32 and the housing half containing the padlock eyelet 38 is placed underneath the propeller 40 with opening 26 accommodating the propeller shaft 42. The housing half containing the latch 34 is then rotated about hinge 32 over propeller 40 until the latch 34 contacts padlock eyelet 38. The latch 34 is then pulled outward, away from the housing 10, such that the padlock eyelet 38 may enter one of the openings 36 in the latch 34. The size of the propeller 40 will govern which opening 36 is preferred. A typical padlock or combination lock (not shown) may then be placed through the opening in padlock eyelet 38 and locked to prevent unauthorized removal of the propeller 40. It is evident that the propeller 40 is now completely enclosed by housing 10 and protected from damage, and is also less likely to cause injury to people that may unintentionally come into contact with the propeller area of the vessel. 
     The housing 10 may be made of any durable material, such as steel or aluminum. It may also be made of plastics heavy enough to resist tampering by would be thieves. Various sizes of the device may be produced to accommodate propellers of varying sizes. To accommodate commonly used propellers on outboard motors of moderate size the housing should be between 10 inches and 18 inches in diameter at its widest point, and preferably near 14 inches. It should have a depth of between 5 inches and 10 inches, preferably near 7 inches. The rear of the housing should be truncated to provide a rear surface 24 of between 4 and 8 inches in diameter, preferably near 6 inches. The opening at the rear of the housing should be slightly larger than the propeller shaft 42 which it must accommodate. The required opening will be approximately 41/2 inches in diameter for many commonly used propellers and motors.