Improvements in Propelling Apparatus for Boats.
Year: 1896

page_text: Date of Application, 7th May, 1896-Accepted, 27th June, 1896
Improvements in Propelling Apparatus for Boats.
I, ARTHUR CECIL CARLON AZEMAR, Master Mariner, of 30, Kloster Strasse,
Ploen, Holstein, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention relates to an improved propelling apparatus for use with small
boats, and has for its object to provide an arrangement which will enable the boat
to be propelled more rapidly than by oars without requiring great power.
In carrying out my invention I propose to employ a light metal or other frame
extending over the sides of the boat, and provided with a screw propeller on each
side. The propellers are made with a number of light blades curved or placed at
an angle so that when revolved they will cause the boat to move to the front or
rear. These propellers are revolved by means of a hand wheel provided with cogs,
or a separate toothed wheel, which serves to drive a small wheel connected with
chains to the propellers. On turning the hand wheel the propellers are thus revolved
at a proportionate rate, utilising the power in the most economical manner.
In order that the invention may be more clearly understood, reference is had to
the accompanying sheet of drawings, in which Fig. 1 is a rear view of a boat fitted
with my invention, Fig. 2 is a side view of the same, and Fig. 3 shows the frame
collapsed. Fig. 4 shows a modification.
According to Figs. 1, 2 and 3, the frame is formed with two legs A pivoted
together at their upper end a. The frame at one side is provided with an exten-
sion a serving to carry the hand wheel B by which the mechanism is operated.
This wheel is furnished with the teeth b, the toothed part being preferably of smaller
diameter than the wheel. This serves to drive a small toothed wheel C preferably
of considerably smaller diameter so that on one turn of the hand wheel the
small toothed wheel will revolve several times. The lower ends of the frame
carry the propellers D formed in any suitable manner two blades being employed
in the arrangement shown. To drive the propellers from the toothed wheel C
the chains c, enclosed in the hollow legs A, are employed similar to the chain
commonly used on cycles. These chains are driven by teeth on the axle of the
wheel C and the propellers are also provided with small toothed wheels.
Instead of this arrangement bevel gearing may be employed to transmit power.
The frame is fixed to the boat E by means of the clamps F at each side so that the
legs A extend on each side of the boat at the stern.
As shown in Fig. 3 the legs can collapse allowing the frame to be stored in a
small compass.
In a modification shown in Fig. 4 a larger frame A' is employed provided with
stays a². The hand wheel B is carried at the centre of the frame and engages
with the two toothed wheels C at the upper ends of the side legs. Both wheels
are thus driven together actuating both the propellers. As the propellers are
driven in opposite directions they are made respectively right and left handed.
This arrangement is especially applicable for boats of larger size in which two
persons can be employed for driving purposes.
In order that the propellers may be enabled to turn without much friction, I
prefer to make a cup bearing into which the end of the spindle carrying the
propeller projects. Any other form of bearing may be used which will reduce the
friction to the smallest possible amount. The propellers should be made of small
pitch and driven at a considerable speed to get the best effect.

page_text: When desired the apparatus can be at once detached from the boat or fixed in
place by means of the clamps so that the boat may be used as an ordinary rowing
boat when preferred.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
(1) A new or improved propelling apparatus for boats consisting of a detachable
frame clamped or otherwise secured to the boat, having legs projecting at each side
and carrying screw propellers, connections from the said propellers to the upper
end of the frame, and means for operating the same by hand, substantially as and
for the purposes specified.
(2) In an improved apparatus for boats the combination with a detachable metal
frame secured to the boat by clamps or other means, having legs projecting over
the sides and screw propellers at the extremities of the said frame, of a chain
connection from the propellers to the upper end of the frame, and a hand wheel
operating the same, substantially as and for the purposes specified.
(3) The improved propelling apparatus for boats consisting of a frame formed
with two hinged legs clamped or otherwise secured to the edge of the boat having
screw propellers at each extremity, chain connections from the said propellers, and
a hand wheel for operating the same substantially as described and shown in
Figs. 1, 2, and 3 of the drawings, and for the purposes specified.
(4) The improved propelling apparatus for boats consisting of a detachable metal
frame clamped or otherwise secured to the boat, having screw propellers at each
extremity and chain connections from the said propellers to the upper end of the
frame at each side, toothed wheels and hand wheel gearing into the same, substan-
tially as described and shown in Fig. 4 and for the purposes specified.
Dated this 7th day of May 1896
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.