AN IMPROVED SYSTEM OF SCREW PROPULSION FOR ACCELERATING THE SPEED OF SHIPS, BOATS, AND PROVISIONAL SPFICATION
Year: 1881

page_text: LETTERS PATENT to John Wilkinson, of Park Road, Blackpool, in County
of Lancaster, Gentleman, for an Invention of "AN IMPROVED SYSTEM OF
SCREW PROPULSION FOR ACCELERATING THE SPEED OF SHIPS, BOATS, AND
PROVISIONAL SPECIFICATION left by the said John Wilkinson at the
Office of the Commissioners of Patents on the 12th August 1881.
JOHN WILKINSON, of Park Road, Blackpool, in the County of Lancaster,
Gentleman. "AN IMPROVED SYSTEM OF SCREW PROPULSION FOR ACCELERATING
THE SPEED OF SHIPS, BOATS, AND OTHER VESSELS THROUGH WATER."
The object of this Invention is to augment and accelerate the speed of ships,
boats, and other vessels through water by a combind system hereinafter described.
1st. I use two shafts to work at the stern of the vessel carried by suitable
bearings fixed in a firm and substantial manner to the vessel.
2nd. I shall require a longer screw race for the working of the propellers than
those generally used, the length to be in an horizontal direction.
3rd. Upon the two shafts I secure a number of single bladed propellers, part of
which are of right hand motion and part of left hand motion, the right hand
propellers being secured upon one shaft and the left hand propellers upon the
other.
4th. Upon the shaft containing the righthand propellers, the propellers are set
apart as their diamiter and pitch may demand, and are set back from each other
so that they will work in succession to each other. Upon the shaft containing
the lefthand propellers, the propellers are simularly set apart and back from cach
other and work likewise in succession.
5th. When the propellers are ultimately secured, the possition of the propeller
blades upon one shaft must be a counterpart of the other.
6th. When the shafts are set in possition they are coupled so that their relatave
possition may be mentained, and in such a manner that the propeller blades may
work in pairs alternatly and towards each other when revolving, and in such
Din G11

page_text: manner that the stroke or flow from each pair of propellers shall be taken up
and carried aft by each succeeding pair of propellers at at every revolution of the
shafts.
•
7th. The shafts are so arranged that they can be uncoupled to assist in
manupalating the vessel when required.
8th. The number of propellers will have to be determined by the size of the
vessel and power applied, and they may be increaced or otherwise according to the
requirements of the case; and if essential the propellers may be diminished in their
diamitor.
9th. When reversing, the action or motion is simular in its effect as when going
ahead.
10th. The within described method may be used by being placed below the bull
of the boat or vessel, the propelling arrangement being carried out as described in
this Specification.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Wilkinson in the Great Seal Patent Office on the 11th February
1882.
JOHN WILKINSON, of Park Road, Blackpool, in the County of Lancaster,
Gentleman. "AN IMPROVED SYSTEM OF SCREW PROPULSION FOR ACCELERATING
THE SPEED OF SHIPS, BOATS, AND OTHER VESSELS THROUGH WATER."
The object of this Invention is to augment and accelerate the speed of ships,
boats, and other vessels through water by a combined system hereinafter discribed.
1st. I use two shafts to work at the stern of the vessel carried by suitable
bearings fixed in a firm and substantial manner to the vessel.
2nd. I shall require a longer screw race for the working of the propellers than
those generally used, the length to be in an horizontal direction.
3rd. Upon the two shafts I secure a number of single bladed propellers, part of
which are of right hand motion and part of left hand motion, the right hand
propellers being secured upon one shaft and the left hand propellers upon the
other.
4th. Upon the shaft containing the right hand propellers, the propellers are set
apart as their diameter and pitch may demand, and are set back from each other
so that they will work in succession to each other. Upon the shaft containing the
left hand propellers, the propellers are similarly set apart and back from each
other and work likewise in succession.
5th. When the propellers are ultimately secured, the position of the propeller
blades upon one shaft must be a counter part of the other.
6th. When the shafts are set in position they are coupled so that their relative
position may be maintained, and in such a manner that the propeller blades may
work in pairs alternately and towards each other when revolving, and in such a
manner that the stroke or flow from each pair of propellers shall be taken up and
carried aft by each succeeding pair of propellers at every revolution of the shafts.
The shafts may also be uncoupled when required.
This system is also applicable beneath bottom of vessel.
The Invention will be well understood by referance to the accompanying
Drawings, in which Fig. 1 is a side view of ship or vessel, and shews the horazontal
screw race "a" running underneath stern of vessel; also the starboard shaft "6"
with the propeller blades "c, c, c, c, c, c," arranged thereon. The bearing for
carrying extreme end of shaft is shewn marked "d.”
t
Figure 2 is a bottom view of the vessel shewing the two shafts "b, b;" also
the blades of propellers marked respectively c, c, c, c, c, c, c, c, c, c, c, c. This Drawing
gives the working position of the various parts.
Figure 3 is an end or stern view of ship or vessel.
And having now described the nature of my Invention, I claim as novelty the
method of arrangement and distribution of right and left hand single blade
propellers upon two shafts, as shewn in Figure 2, the said shafts revolving in
opposite directions and towards each other, and working in pairs successively, and
in such a manner that their combined action will generate a resisting flow of water
from the face or striking surface of one line of propellers to those of the other, and
visa versa; and also a taking up or discharging effect tending to condense and

page_text: solidify the water behind the propellers and give an increased speed to any ship,
boat, or vessel having power to propel the same.
In witness whereof, I, the said John Wilkinson, have hereunto set my hand
and seal, this Ninth day of February, in the year of our Lord One thousand
eight hundred and eighty two.
JOHN WILKINSON. (L.S.)