IMPROVE- MENTS IN PADDLE WHEELS
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
JAMES GIFFORD, of Gloucester Place, in the County of Middlesex, Surgeon,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Seventh day of September, in the first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William James Gifford, Her especial licence, full power, sole privilege and
authority, that I, the said William James Gifford, my exors, adññiors, and
assigns, or such others as I, the said William James Gifford, my exors,
adiñors, or assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVE-
MENTS IN PADDLE WHEELS;" in which said Letters Patent is contained a proviso
that I, the said William James Gifford, shall cause a particular descrip-
tion of the nature of my said Invention, and in what manner the same is
to be performed, to be inrolled in Her said Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being there-
unto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William James Gifford, do hereby declare the nature of my said Invention,
and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being had

page_text: to the Drawings hereunto annexed, and to the ngures and letters marked thereon,
that is to say:-
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents the side view of one arrangement of paddle wheel, con-
structed according to my improvenients, a being the main or driving shaft,-to
which the side framings of the paddle wheel are attached by keys or otherwise,
as is well understood. The Drawing shews the parts which come next the
ship or vessel's side. b is an enlarged axis, which is placed eccentric to the main
axis a; this eccentric axis b is bolted or otherwise securely fixed to the ship's or
vessel's side, and becomes the means of controlling and governing the angles
taken by the float boards, in their entering and leaving the water. c is a
circular collar, which moves on the eccentric axis b, such collar being con-
nected to the main wheel by means of the cranks d, d, d, d, or the same may
be said to be parallel rods, as they at all times retain a parallelism one to the
other, in consequence of the axis at one end of each of the rods d moving in
the circular frame e of the main wheel, and the axis at the other end of each
rod d moving in the collar c, hence the revolution of the main wheel will cause
the collar c to move round on its eccentric axis b, together with the various
rods, to the float board, hereafter to be described.
I would here remark, that thus far the combination of the parts is not new
as applied to paddle wheels, a similar arrangement having been described
several years ago by a Mr. Buchanan, and is a construction of wheels well
known to mechanics, but in his wheel, the float boards were attached to the
axes of the cranks d, which moved in the eccentric wheel, which the collar c,
above described, may be said to represent, and according to such arrangement
the float boards were at all times parallel to each other; but my Invention
commences at a point beyond the combination thus far described, for in place
of having the float boards applied to axes of the cranks d, as was formerly the
case, the float boards f,f, are affixed to axes carried by the side framings of
the main wheel, those axes having suitable bearings, to allow of movement.
9, 9, 9, are a series of connecting rods, attached by pin joints to the collar c,
and at their other ends they are attached to the arms or cranks, which are
affixed to the axes f¹ of the float boards, as is clearly shewn in the Drawing.
By this arrangement, I am enabled to obtain the capability of making wheels
the float boards of which may be caused to enter and leave the water at any
desired useful angle, which is a result that could not be obtained by what is
called Buchanan's arrangement of wheel. It will be seen that the float boards
of each of the wheels are placed considerably above their respective axes, and
much less below. The object of this arrangement is, that as the upper portion

page_text: of the surface of each float board has to pass through a less circumference,
according as the point of the surface chosen is nearer to or farther from
the centre of motion of the main wheel, hence it is well known that the pressure
of the water will be more or less on the float boards according to the speed or
distance through which each part of each float board passes in a given time;
and it is important as nearly as possible to balance the pressures on the axes
of the respective float boards, in order, as much as possible, to prevent strain on
the rods which govern the positions of the float boards, where working in the
water. And I would remark that the Drawing shews the float boards as being
about three fifths above and two fifths below their respective axles, which I
believe to be a good practical arrangement. It should be stated, that I am
aware that moveable float boards have been before attempted to be balanced
on their axes, but in such cases the float boards were not controlled in their
action by an eccentric axis and connecting rods.
Figure 2 is a side view, Figure 3 an edge view, and Figures 4 and 5 are
enlarged view of some of the parts of a paddle wheel, having some further
improvements applied thereto, so far as the application of the eccentric axis
and the rods. The collar c are similar to those above described, and are
marked with the same letters of reference, the difference of the present arrange-
ment being, that the angles at which the float boards enter and leave the
water being capable of change, in consequence of the position of the eccentric
axis being capable of variation by this arrangement, should it be found desirable,
owing to the load, and consequently the line of floatation varying, or the
engines on board being prevented making the ordinary number of strokes, and
the vessel forced through the water at a different speed to that at which the
angles (of entering and leaving the water) had been calculated to produce the
fullest effect, the angles may be varied some degrees, in order to accommodate
them to the speed of the vessel, and the number of strokes the engine is
making at any given time; and it may be desirable to remark that, according
to the present knowledge on the subject, it is considered that each float board
should be so arranged and governed as to be capable of entering and leaving
the water at a tangent to the cycloidal line, generated by a point about the
centre of the float board. Whether such be or be not, the correct theory is not
material to Invention, other than that my improvements will enable the
engineer to produce a wheel. The float boards at entering and also at leaving
the water may be controlled to assume the angles which may, from the above
theory, or from practical trials of any vessel, be considered the best. In order
to accomplish this capability of change; in addition to the arrangement of
machinery above given, I apply a means of moving the position of the eccentric
my

page_text: axis. This apparatus will more clearly be seen at Figures 4 and 5, where the
parts are on enlarged scale. i, i, is a quadrangular frame, moving on the cranks
R, which arc affixed on the axes of the cranks d, and in place of the crank d
being connected directly with the circular collar c it is connected therewith by
means of connecting rods and pin joints d', as is clearly shewn in the Drawing,
and the circular eccentric axis b, in place of being bolted to the ship's side, and
made a fixture, is to be capable of movement as follows:-- is a lever within
the ship or vessel; this lever is affixed to the axis b, moving in suitable bearings.
m is part of a toothed wheel affixed on the axis l, and takes into the rack n
formed in the eccentric axis b, such eccentric axis being formed of two plates,
having, at their outer circumference, semicircular grooves, to receive the. en-
larged circular ring on the collar c, which is clearly shewn at the section,
Figure 5; and these plates of which the axis b is formed are capable of being
set up to each other as the parts wear, in order to keep the working surfaces
correct, as is clearly shewn in the Drawing. o, o, is a curved opening formed in
a plate p, which is securely bolted to the ship's side. q is a pin, which works
within the opening, and passes through the lever or handle ; hence, by means
of the screw nut, the lever or handle k can be retained in any position to which
it
may be placed in the opening o, and consequently the eccentric axis b. The
eccentric axis b, in place of being bolted to the ship's side, is supported and
carried by the plate r, which is securely bolted or affixed to the ship's side, and
the eccentric axis 6 has a plate s affixed to it, which rests on the upper curved
face of the plater, and is guided thereby, there being a slot or opening t through
the axis b, and the lower portion of the plate r passes through that slot, and
supports the axis b, the axis 6 being securely retained to the plater by the
plate v, as is clearly shewn in the Drawings; hence, the position of the axis b
will depend on the position of the lever handle k. Thus far the mode of con-
trolling the movement of the float boards is on the same principle; the two
construction of wheels only differing in as much as one of them has a capability
of moving the eccentric axis, in order to allow of a change in the angles after
the wheel is made and applied to the ship's side.
I will now proceed to describe an arrangement or combination of paddle
wheel, made according to another part of my improvements. In this arrange-
ment, see Figs. 6 and 7, the float boards are attached to their respective axes,
as above explained, and each axis has its crank and connecting rod, but in
place of the connecting rods being attached to a collar or complete ring c, as
before explained, the connecting rods are attached by pin joints to sliding
pieces, which are each sections of a circle, and move within a groove A, which
is eccentric to the main shaft, such eccentric groove or guide being affixed to

page_text: the vessel's side. And I prefer the groove to be made in two plates, which
being bolted together, has a space which allows of the connecting rods to pass
round. B,B, are a series of connecting rods, one to each of the connecting rods
which work the float boards, such connecting rods being attached at one end
to the boss of the wheel, and the other ends one to cach of the connecting rods
by pin joints; by this arrangement any useful angle to the float boards may be
obtained.
Having thus described the nature of my Invention, and the modes of
combining the same, I would have it understood that I lay no claim to any of
the parts separately. But what I do claim is, the mode of obtaining the
desired angle by means of connecting rods applied to a collar or ring, which
is caused to revolve on an eccentric axis by means of cranks or parallel rods,
as above described at Figures 1, 2, 3, 4, and 5. And also the mode of giving
a further capability of varying the angles, by movement of the eccentric axis,
as described at Figures 2, 3, 4, and 5.
Secondly, I claim the mode of constructing a paddle wheel, as described in
Figures 6 and 7.
And lastly, I claim the mode of equalizing the pressure on the two sides of
the axis of the float board, when such float boards are governed and controlled
in their movement by an eccentric axis and connecting rods, as above-
described.
In witness whereof, I, the said William James Gifford, have hereunto
set my hand and seal, this Seventh day of March, One thousand
eight hundred and thirty-eight.