Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS599125 A
Publication typeGrant
Publication dateFeb 15, 1898
Filing dateApr 12, 1897
Publication numberUS 599125 A, US 599125A, US-A-599125, US599125 A, US599125A
InventorsHenry H. Fefel
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 599125 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

l2' Sh'eetS-Sheet l.

Patented Feb.. 15 1898;"

(No Model.)



Tu: Nonms MYERS co, PNoToLIYHO.. wAsmNc'am n. cv

(No Model.) 2 Sheets-Sheet 2.



No. 599,125. Patented Feb. 15,1898.


PATENT ninos.



SPECIFICATION forming part of Letters Patent No. 599,125, dated February 15, 11898.

Application filed April 12,A 1897. Serial No. 631,876. (No model.)

tions of the propeller in a given time such` vessels lose rather than gain in speed when the propellers are revolved at a very high rate, the theory being that the extraordinary rapid rotation of the screw causes the formation of a cylinder or column of water, which being of about the diameter of the propeller and whirling therewith offers no purchase for the screw, and consequently retards the movement of the vessel.

The object of this invention is to provide a construction by which this objectionable feature may be avoided, whatever the rate' of 'speed of the propeller, and, furthermore, to

provide a simple and efficient means for transmitting the power fromthe motor to the propeller-shafts.

The invention therefore consists in the use of two screw-propellers of different diameters mounted onebehind the other on concentric shafts,and means, more particularly described hereinafter, whereby the shafts are rotated, and a relative diiference of speed between the two rotating shafts constantly maintained.

In the drawings, Figure 1 is a View showing my improved mechanism in plan, the dotted line indicating the outline of a boat to which the mechanism may be applied. Fig. 2 is an enlarged view, partly in section and partly in elevation, ofthe power-transmitting mechanism. Fig. 3 is a sectional view, still further enlarged, on the line x a; of Fig. 2. Fig. 4 is a face view of one of the roller-carriers; and Fig. 5 is a sectional view of one of the rollercarriers, showing a means for adjusting the same.

A represents a horizontal shaft suitably mounted in bearings and having iixedly secured at one end thereof the disk or wheel B.

The shaft A is directly connected with a motor, (indicated at 0,) which may be of any preferred type of steam, electric, or gas engine. One face of the disk B is provided, as shown, with a series of radial grooves or slots b b h b', the sides or walls thereof being slightly convergent.

A shaft D is mounted in bearings d cl, ex tends to and through the stern of the vessel, and is provided at its outer end with a propeller E. The shaft D, as'shown, is hollow and surrounds a second shaft G,which extends to and slightly beyond the end of the shaft D, where it also is provided with a screw-propeller, (indicated at K,) and preferably of smaller diameter than propeller E.

The shafts D and G are mounted in a line about midway the center and periphery of the disk B, and the inner end of the shaft G carries a series of tapered rollers g g g, mounted on studs on a suitable carrier H. The carrier stands adjacent lthe face of the disk B and the rollers project within the grooves or slots thereof. The drawings show a set of three rollers for the carrier H and twelveradial vgrooves in the disk B or two sets of six grooves each. The rollers g g g engage and are acted upon only by the set of grooves marked b b b. Rotation of the shaft A and disk B causes the shaft G and propeller K to rotate at a speed double that of shaft A. This result, it is be-l 'm 'm fm, which engage and are operated by the set of radial grooves b Z9 Z7.

By providing a distinct set of grooves for the rollers of each of the carriers H and L the carriers may be set so as to have the rollers mesh in a manner similar to that of the teeth of gear-wheels. Thus but one roller at a time crosses the center of the disk B, and

interference between the carriers is avoided.v

If but one-half the number of grooves were used, the carriers would lock.

A pinion N is formed integrally with or otherwise fixed to the carrier L and engages the gear-wheel F, secured tothe inner end of the shaft D. The gear-wheel F being about double the size of pinion N,rotation of the disk B causes the hollow shaft D and propeller E IOO to rotate at a speed about equal to that of the'shaft A.

By this construction many of the advantages common to twin screws as ordinarily used are attained and in addition great economy of space. Furthermore, while each of the two screws exerts a propelling force of high efficiency for the vessel their unequal size and unequal speed disturb the water in such manner as to effectually prevent the formation of a column or cylinder of water, with its attendant ill effects, as hereinbefore referred to.

It is desirable that some means be employed for adjusting the position of the carriers or the rollers with respect to the disk B. In Fig. 5 is shown one simple method of accomplishing this. The carrier is feathered o'n the shaft and abuts against a nut s, (shown in dotted line,) which turns on a threaded portion 1U of the shaft. By turning the nut the carrier may be forced toward the disk and the tapered rollers advanced farther into the grooves b b' to take up any unnecessary play that might exist between said grooves and tapered rollers. This method of adjustment may be applied to either carrier.

Asthe two shafts D and G rotate in opposite directions, the blades of the two screws should be set at opposite angles. dicated in Figs. l and 2.

Having described my invention, I claim- 1. In boat-propelling mechanism the com- It is so inbination of a motor, a disk driven thereby, a series of radial slots in said disk, a carrier provided with suitable rollers or projections engaging with each alternate slot in said disk, a second carrier provided withsimilar rollers or projections engaging each of the other slots in said disk, a pair of concentric shafts carrying propellers and suitable connections between said carriers and shafts whereby the shafts are driven substantially as described.

2. In boat-propelling mechanism the combination of a motor, a grooved disk driven thereby, a shaft G, having thereon a propeller and a suitable carrier provided with rollers or projections engaging the grooves in said disk, a second shaft parallel with the first and havingv thereon a suitable carrier provided with rollers or projections engaging the grooves in said disk, and also having a pinion thereon, and `a hollow shaft or sleeve surrounding Ishaft G, provided with a propeller and having thereon a' gear-wheel of suitable diameter engaging with the said pinion, whereby the propellers are operated at different speeds, substantially as described.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 5th day of April,



Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4619584 *Feb 2, 1984Oct 28, 1986Ab Volvo PentaDouble propeller drive for boats
US5514014 *Nov 29, 1994May 7, 1996Sanshin Kogyo Kabushiki KaishaOutboard drive transmission
US5522703 *Oct 26, 1994Jun 4, 1996Sanshin Kogyo Kabushiki KaishaPropulsion system seal for outboard drive
US5556312 *May 31, 1995Sep 17, 1996Sanshin Kogyo Kabushiki KaishaBearing arrangement for marine transmission
US5556313 *May 31, 1995Sep 17, 1996Sanshin Kogyo Kabushiki KaishaOutboard drive transmission
US5558498 *May 31, 1995Sep 24, 1996Sanshin Kogyo Kabushiki KaishaPropeller shaft assembly for marine propulsion system
US5575698 *Nov 29, 1994Nov 19, 1996Sanshin Kogyo Kabushiki KaishaOutboard drive transmission system
US5597334 *Jun 5, 1995Jan 28, 1997Sanshin Kogyo Kabushiki KaishaOutboard drive transmission system
US5601464 *Nov 30, 1994Feb 11, 1997Sanshin Kogyo Kabushiki KaishaTransmission system for counter-rotational propulsion device
US5697821 *May 31, 1995Dec 16, 1997Sanshin Kogyo Kabushiki KaishaBearing carrier for outboard drive
US5716247 *Jun 27, 1996Feb 10, 1998Sanshin Kogyo Kabushiki KaishaBearing arrangement for marine transmission
US20130129514 *May 23, 2013Becker Marine Systems GmgH & Co. KGPropeller arrangement, in particular for watercraft
Cooperative ClassificationB63H5/10, B64C11/48