US3148736A

US3148736A - Propeller

Info

Publication number: US3148736A
Application number: US182484A
Authority: US
Inventors: Skopyk Joseph
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-03-26
Filing date: 1962-03-26
Publication date: 1964-09-15
Anticipated expiration: 1981-09-15

Description

Sept. 15, 1964 J. SKOPYK 3,143,736

PROPELLER Filed March 26, 1962 2 Sheetls-Sheet 1 INVENTOR.

Sept. 15, 1964 J. SKOPYK 3, 6

PROPELLER Filed March 26, 1962 2 Sheets-Sheet 2 INVENTOR.

United States Patent Office 3,143,73 PROPELLER Joseph Skopyk, 3911 Bloor'St. W., Islington, Toronto 18, ()ntario, Canada Filed Mar. 26, 1962, Ser. No. 182,484 Cla ms, (Cl. 170-176) This invention relates to improvements in water propulsion devices and more particularly to improvements in propellers.

It is well known that a great deal of propulsivepower is lost when utilizing propellers, of the prior art due mainly to centrifugal force applied to the water in the vicinity of the propeller blades causing turbulence and cavitation.

Furthermore, due to the pressures at the tips of the blades, the tip area is necessarily restricted in order to prevent such pressure in damaging the propeller.

It is, therefore, an object of the present invention to provide a propeller which will substantially obviate the movement away from the propeller due to centrifugal force.

It is another object of the present invention to provide a propeller which will divert all the water rearwardly with a consequent forward reaction being transferred to the propeller.

It is still another object of the invention to provide a propeller which, compared to conventional propellers may have an extremely large blade area in comparison to its diameter and thereby absorb more engine power and translate it into propulsive power.

A further object of this invention is to provide a propeller which, by supporting the blade tips in a tunnel like housing, will also permit the formation of the blades in a highly efiicient but hitherto a practical conformation.

It is yet another object of this invention to provide a propeller which may be adapted for use with either outboard or inbroad engines, as required.

These and other objects and features of this invention will become apparent when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a part sectional, part sectional, perspective view of a propeller embodying the present invention adapted for use with an inboard engine.

FIG. 2 is a front end elevation of a propeller similar to that illustrated in FIG. 1, adapted for use with an outbroad motor.

FIG. 3 is a sectional side elevation of the propeller illustrated in FIG. 2 taken on the line 33.

FIG. 4 is a fractional side elevation of the stern of a boat powered by inboard engines incorporating a propeller as illustrated in FIG. 1.

FIG. 5 is a fractional, side elevation of the stern of 'a boatpowered by an outboard motor by embodying a propeller as illustrated in FIG. 2.

Referring to FIG. 1, a propeller houses a plurality of substantially identical blades 11 havingtheir 'root ends 12 firmly aflixed to a central, substantially cylindrical hub 13 and their tips 14 being attached to and supported by a tunnel member 15.

It will be noted that hub 13 is of substantially conventional design having a centre bore 16 and a keyway 17 formed therein, bore 16 being adapted to slidably accommodate a drive shaft 18 and its attendant key 19. Although not shown, propeller 10 is retained on shaft 18 by conventional nut and thread means located behind the rear surface 20 of hub 13.

Referring also to FIGS. 2 and 3, a propeller 21 is similar in all respects to propeller 10 as described with the exception of its hub 22 which is adapted for attach- 3,148,736 Patented Sept. 15, 1964 ment to an outboard motor by means of two diametrically opposed threaded holes 23 -23. The blades 11 and tunnel member 15 are however identical to those described on propeller 10 and are numberedas such in FIGS. 2 and 3 for clarity. V

Blades 11 are of generally volute configuration, hay: ing arcuate leading edges 24 substantially coplanar with The design of blades 11 is such that water contained within tunnel 15 is caused to move rearwardly thereof during rotation of the propeller with the minimum of turbulence, the obliquity of the trailing edges 25 causing the water flowing through the unit to leave the vicinity of the blades progressively and thereby substantially obviate the formation of swirl currents and the like which normally tend to decrease the efiiciency of conventional propellers.

Furthermore, the presence of tunnel 15 in addition to maintaining a full bore of water around blades 11, directs the Water rearwardly in a jet eifect, thereby increasing the thrust available from

propeller

10 or 21.

The truncated conical configuration of tunnel 15 as illustrated increases this jet effect but the maximum efiicient degree of slope of the side walls thereof varies with the other design factors such as length, diameter, and speed of operation.

It should also be noted that tunnel 15 may be of right cylindrical configuration which, although not as efficient as the conical design, still provides more useful work from a given power source than a conventional propeller, and, under certain circumstances, may be easier and cheaper to manufacture than the conical type.

FIG. 4 illustrates propeller 10 of FIG. 1 attached to a boat 30 equipped with an inboard engine, shaft 18 thereof, as previously illustrated being the shaft provided originally with boat 30.

FIG. 5 shows propeller 21 of FIG. 2 attached to the outboard motor 31 of a boat 32 by means of hub 22 as described, the positioning of threaded holes 23 allowing propeller 21 to be bolted to the propeller drive mechanism 33 in the conventional manner.

The general design of the individual parts of the invention as explained above may be varied according to requirements in regard to manufacture and production thereof, While still remaining within the spirit and principle of the invention, without prejudicing the novelty thereof.

The embodiments of this invention in which an exclusive property or privilege is claimed are defined as follows:

1. A propeller including a plurality of substantially identical blades; each of said blades having a root end, a tip, a leading edge and a trailing edge; a centre hub supporting said blades at said root ends; a tunnel member supporting said tips; said tunnel member and said tips being elongated rearwardly of said hub; said blades being of volute configuration; said volute configuration extending at least half the inner circumference of said tunnel member; and means for attaching said hub to conventional driving means.

2. A propeller as defined in claim 1 in which said leading edges of said blades are substantially coplanar with ,3 Y Q the forward surface of said hub and the forward edge of said tunnel member.

3. A propeller as defined in claim 1 in which said tip and said trailing edge of each of said blades spiral Iearwardly within said tunnel member and converge at a point adjacent the rear edge of said tunnel member.

4. A propeller as defined in claim 2 in which said tip and said trailing edge of each of said blades spiral rearwardly within said tunnel member and converge at a point adjacent the rear edge of said tunnel member.

5. A propeller as defined in claim 4 in which said tunnel member is of truncated conical configuration, having wide and narrow open ends, said wide end being foremost.

References Cited in the file of this patent UNITED STATES PATENTS Arnold June 18, 1912 Johannesen Sept. 8, 1959 Geske Ian. 1, 1963 FOREIGN PATENTS Great Britain 1868

Claims

1. A PROPELLER INCLUDING A PLURALITY OF SUBSTANTIALLY IDENTICAL BLADES; EACH OF SAID BLADES HAVING A ROOT END, A TIP, A LEADING EDGE AND A TRAILING EDGE; A CENTRE HUB SUPPORTING SAID BLADES AT SAID ROOT ENDS; A TUNNEL MEMBER SUPPORTING SAID TOPS; SAID TUNNEL MEMBER AND SAID TIPS BEING ELONGATED REARWARDLY OF SAID HUB; SAID BLADES BEING OF VOLUTE CONFIGURATION; SAID VOLUTE CONFIGURATION EXTENDING AT LEAST HALF THE INNER CIRCUMFERENCE OF SAID TUNNEL MEMBER; AND MEANS FOR ATTACHING SAID HUB TO CONVENTIONAL DRIVING MEANS.