Improvements in and connected with Sails for Boats and other Vessels.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Sails for Boats and other
Vessels.
I, FREDRIK LJUNGSTROM, of 37, Kommendorsgatan, Stockholm, in the Kingdom
of Sweden, Mechanician, do hereby declare the nature of this invention to be as
follows:-
The object of this invention is to enable sails of greater superficial area to be
carried by boats and other vessels than heretofore, and whereby greater stability,
and greater speed, can be obtained than has heretofore been possible, without
endangering the safety of the boat; the further object being to so arrange and
construct the said sails that the force of the wind thereon tends rather to lift or
support the boat than to submerge it, as has been the case hitherto.
According to my invention I arrange or construct the sails with rigid edge
frames, and such frames are suspended by the upper edges from say a yard or cross
piece on the mast, while the lower edges of the sail frames are held by cords or the
like to, or at a proper distance from, a lower yard or cross piece on the mast.
By such an arrangement as above broadly stated, and means being further
provided whereby the angle of the plane of the sail frames may be varied with
respect to the vertical longitudinal central plane of the vessel, say by rotating the
carrying yards about horizontally upon the mast, I am then enabled, firstly to place
the sail frames at a proper angle with the longitudinal axis of the vessel, and
secondly to allow the sail frames to be turned upon the upper yard to such an angle
with the horizontal plane, that the wind acts upon the sail frames at such an angle
that the boat or other vessel while being propelled or driven forwards as usual, will
not be heeled over to any undesirable extent, although the superficial area of such
sail frames may be greatly in excess, in proportion to the size of boat, to the area
usually employed, in fact a kind of lifting action is imparted to the boat's sail or
sails.
The mechanical construction I employ to carry out my invention may be
greatly varied according to circumstances; thus I may form frames of steel tube
having canvas, fabric, or other material stretched thereon, and the fabric may be
so fixed in each frame that it can at will, either be caused to entirely cover the
space between the frames or only partly span such space. The yards may be fixed
to the mast or masts and the latter may then be constructed to be revolved in its
step by any suitable means, mechanical or otherwise, in order to set the sails at any
required angle with the longitudinal axis of the vessel; or the upper and lower
yards may be mounted upon a sleeve tube upon the mast, or in other cases each
yard may be caused to be capable of revolution around the mast.
In other cases the sail frames may be fixed, say in a plane at right angles to the
upper end of the mast and the latter then mounted in a suitably jointed carrier at
or near its lower end, so that the said mast may be inclined to bring the surface of
the sail frames at the proper angles to the horizontal plane.
1000

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Sails for Boats and other
Vessels.
I, FREDRIK LJUNGSTROM, of 37, Kommendorsgatan, Stockholm, in the Kingdom
of Sweden, Mechanician, 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:-
The object of this invention is to enable sails of greater superficial area to be
carried by boats and other vessels than heretofore, without endangering the safety
of the boat, and whereby greater stability and greater speed can be obtained than
has hitherto been possible, the further object being to so arrange and construct
the said sails that the force of the wind thereon tends to lift the boat rather than
submerge it, as has been the case hitherto, while the equilibrium of the boat is not
disturbed at all, or only in a very small degree.
With this object in view I suspend the sails pendulum-wise from a yard, the
latter being capable of revolution in a plane at right angles to the mast, by which
the yard is supported, and I provide means such as sheets whereby the lower edges
of the sails may be retained at a proper distance from the mast so that the sail
surface may be set at such an angle that the normal component of the wind
pressure upon the sails passes about through the centre of gravity of the boat,
whereby the before-mentioned objects are obtained.
In some cases I fit the lower edges of the sail surface, which edges may consist
of a rigid frame, with boat-shaped floats, and thereby prevent the lower edge of the
sails being submerged.
In the accompanying drawings, at Fig. 1 I have shewn in end elevation, and at
Fig. 2 in plan, an example of my improved sails. Fig. 3 is a detail sectional
elevation of the upper end of a mast. Fig. 4 is an end elevation, and Fig. 5 a plan
view shewing the sails fitted with floats.
Referring more particularly to Figs. 1 and 2, A indicates a sailing boat, which
may be of any desired construction or character, having a mast B. Upon or near
the upper end of this mast B there is arranged a yard C, so fitted that it may be
revolved around the said mast B, or the yard C may be rigidly fixed to the mast B,
and the latter made capable of revolution in its socket in the boat.
The yard C is as shewn, carried within, or passes through, a tubular part C. the
downward branch of which is fitted upon the end of the mast B, and is generally
so arranged that the yard C is not only capable of revolution around the axes of
the mast B, but is also capable of revolution upon its own axis.
From the yard C there extends downwardly depending bars D to and between
which, sails E are attached by any usual or convenient means, say by lacing as
shewn, and thus depend pendulum-wise from the yard C.
The lower edges of the sails E are held by cords or sheets F G, so that the planes
of the sails may be retained at a proper angle, and such sheets F and G may be
fixed to the ends of a lower yard or cross piece H.
By such an arrangement as above broadly stated, and means being provided
whereby the angle of the plane of the sails may be varied with respect to the vertical
longitudinal central plane of the vessel, say by rotating the carrying yards about
horizontally upon the mast, I am then enabled firstly to place the sails at a proper
angle with the longitudinal axis of the vessel A, and secondly to allow the sails E
to be turned upon the upper yard D to such an angle with the horizontal plane,
that the wind acts upon the sails E at such an angle that the boat or other vessel A
while being propelled or driven forwards as usual, will not be heeled over to any

page_text: undesirable extent, although the superficial area of such sails E may be greatly in
excess in proportion to the size of boat A to the area as usually employed.
The mechanical construction I employ to carry out my invention may be greatly
varied according to circumstances; thus I may form complete frames I) of steel tube
having canvas, fabric, or other material stretched thereon, and the fabric may be
so fixed in each frame that it can at will either be caused to entirely cover the space
between the frames, or only partly span such space. The yards CH may be fixed
to the mast B and the latter may then be constructed to be revolved in its step by
any suitable manner, mechanical or otherwise, in order to set the sails E at any
required angle with the longitudinal axis of the vessel A; or the upper and lower
yards CH may be carried in brackets J upon a sleeve tube B' upon the mast Bas
shewn at Fig. 3, or in other cases each yard may be caused to be capable of
revolution around the mast.
The lower parts of the sails E may have floats KK as shewn at Figs. 4 and 5;
in this case the sails E are made of rigid sheets or are stretched in complete rigid
frames D and suspended pendulum-wise from. the yard C all as before described
with reference to Figs. 1 and 2. At the base of each sail or sail frame I pivot a
float K, the connection K' with the float being formed of the centre of its length,
and so that when passing through the water the lengthway axis of the floats will
be maintained parallel with the boat A at all times.
The floats K may be of any desired shape or form, for example as shewn, or cigar
shape, and effectually prevent any submergence of the bases of the sails. I provide
means whereby the mast may be inclined relatively to the boat, such as a joint at
L, and whereby the boat is maintained upon an even keel as shewn, while it cannot
be overturned by any wind pressure, the effect of which would only be to tend to
lift the boat and perchance force the floats K deeper into the water.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim is:-
1. In sailing boats, the combination with a mast or with each mast, of a yard
located at the upper end thereof and capable of revolution in a plane at right angles
to the axis of the said mast, bars or rods depending from and at right angles to the
yard, means whereby the pendant bars may have a swinging or pendulum
movement about the axis of the yard, sails stretched between the pendant bars, and
the yard, and means such as sheets for retaining the lower ends of the pendant rods
at proper distance from the mast, and whereby the sail surface may be set at such
angle that the normal component of the wind pressure upon the sails passes about
through the centre of gravity of the boat, as set forth.
2. In sailing boats, the combination with a mast or with each mast, of a bracket
upon the upper end thereof, a tubular bearing sleeve upon and at right angles to
the bracket, a yard passing through the sleeve and capable of axial rotation therein,
means for axially rotating the mast in its step or bearing, and thereby revolving
the yard, bars or rods depending at right angles from the yard, and jointed thereto,
sails stretched between the bars, and means for retaining the lower ends of the
pendant bars to hold the sail surface at such an angle that the normal component
of the wind pressure thereon, passes about through the centre of gravity of the boat,
as set forth.
3. In sailing boats, the combination with the mast or with each mast, of a sleeve
tube, capable of revolution thereon, a sleeve bracket upon the tube, a yard carried
by the bracket, and extending at right angles to and at the upper end of the mast,
sails pendant from the yard, and jointed thereto, and means for retaining the lower
end of each sail at a required distance from the mast, and whereby the sail surface
shall be at such an angle that the normal component of the wind pressure acting
upon the sail shall pass through the centre of gravity of the boat, as set forth.
4. In sailing boats, the combination with the mast or with each mast, of a yard
located at the upper end thereof, and mounted so as to be capable of revolution in
a plane at right angles to the axes of the mast, rigid frames jointed to the yard and

page_text: pendant therefrom, sails stretched in the frames, and means for retaining the lower
bars of such frames at a proper distance from the mast, and thus holding the said
surface at an angle, whereby the normal component of the wind pressure acting
thereon shall pass through the centre of gravity of the boat, as set forth.
5. In sailing boats, a mast or with each mast, of a yard located at the upper end
thereof, and capable of revolution in a plane at right angles to the axis of the said
mast, rigid or rigidly framed sails, depending pendulum-wise from and at right
angles to the yard, means such as sheets for retaining the sails at a proper distance
from the mast, in combination with a boat-like float located at the lower edge of
each sail frame to prevent the submergence of the sails, means for retaining the
floats parallel with the boat, and means for allowing the mast to incline and the
boat to thereby be maintained level on an even keel, substantially as set forth.
Dated this 17th day of February 1898.
BREWER & SON,
London and Leeds, Agents for the Applicant.