IMPROVEMENTS IN GEARING OR APPARATUS FOR TRANSMITTING MOTION
Year: 1872

page_text: LETTERS PATENT to George Lindsay, of Liverpool, in the County
of Lancaster, Engincer, for the Invention of "IMPROVEMENTS IN
GEARING OR APPARATUS FOR TRANSMITTING MOTION."
Sealed the 9th July 1872, and dated the 12th January 1872.
PROVISIONAL SPECIFICATION left by the said George Lindsay at the
Office of the Commissioners of Patents, with his Petition, on the
12th January 1872.
I, GEORGE LINDSAY, of Liverpool, in the County of Lancaster,
Engineer, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN GEARING OR APPARATUS FOR TRANSMITTING MOTION," to be as
follows:-
For the purpose of transmitting motion I employ (1) right and left
screw threads or helices formed on the driving shaft or on a pulley
or drum secured thereon, gearing into left and right screw threads
or holices formed on the driven shaft or on a pulley or drum secured

page_text: thereon, and (2) a right or left screw thread or helix on the driving
shaft or a pulley or drum secured thereto gearing with a compounding
left or right screw (3) or helix on the driven shaft or a pulley or drum
secured thereto.
By the means described absolute gearing by interlocking is effected 5
with surfaces in rolling contact; and such gearing is noiseless when at
work, is durable, and does not like frictional gearing require frequent
"setting-up" or forcing together of the surfaces.
The screw threads or helices may be of any ordinary form, but I
prefer that the one side should stand at nearly a right angle to the 1
axis, whilst the other side is formed at a greater angle. I prefer too
that the said screw threads or helices on the driving shaft, should be
slightly larger in diameter than those on the driven shaft and also that
the pitch of the driving threads or helices should be slightly less than
those of the driven threads or helices.
1
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Lindsay in the Great Seal Patent Office
on the 12th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
LINDSAY, of Liverpool, in the County of Lancaster, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of January, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Lindsay, Her special licence
that I, the said George Lindsay, my executors, administrators, and
assigns, or such others as I, the said George Lindsay, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein.
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel

page_text: •
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN GEARING
OR APPARATUS FOR TRANSMITTING MOTION," upon the condition (amongst
others) that I, the said George Lindsay, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of
their hands and scals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent

page_text: readily comprehend my Invention, contains views illustrative of practical
details.
Thus, Fig. 1 shows in side elevation a driving shaft a fitted with
a drum 6, whereon are formed right and left screw threads or helices c,
gearing with left and right screw threads or helices d formed on a 5
drum e secured on a driven shaft f. The drums 6 and e are in this
modification of the same size; single threads are shown, and the threads
or helices represent in section wedge and vee gearing.
Fig. 2 is a side elevation of gearing where the driving shaft
is fitted with collars and a pulley or drum formed with a single 1
thread or helix i geared into a corresponding double thread or helixj
on the driven shaft % with collars Z. The thrust collars / and /
are provided for receiving thrust during the transmission of power
in one direction or the other. If the motion is only required in
one direction then one collar each of h and I may be dispensed with.
Fig. 3 is a side elevation of bevel gearing drawn with threads,
square
right and left threads gear with left and right threads. To keep the
threads shown on this modification in proper gear a loop m and sct
nut n are provided. Other means may be adopted for keeping them in
gear during wearing, but I prefer the means shown.
Fig. 4 is a view of part of the driving and driven gearing I prefer.
Here the one side 1 stands at nearly a right angle to the axis,
whilst the other side 2 is formed at a greater angle. A single thread
or helix is delineated, but double, triple, and other threads may be
used.
Fig. 5 is a view in side elevation of a modification, the threads or

page_text: Having now described the nature of my said Invention and par-
ticularized the same, I claim, constructing and employing screw threads
or helices gearing one with another as means for transmitting motion,
substantially as described.
Having now described the nature of my said Invention and par-
ticularized the same, I claim, constructing and employing screw threads
or helices gearing one with another as means for transmitting motion,
| substantially as described.
In witness whereof, I, the said George Lindsay, have hereunto set
my hond and cool the 0th day of July in the year of our Lord
ticularized the same, I claim, constructing and employing screw threads
or helices gearing one with another as means for transmitting motion,
substantially as described.
In witness whereof, I, the said George Lindsay, have hereunto set
my hand and seal, the 9th day of July, in the year of our Lord
One thousand eight hundred and seventy-two.
In witness whereof, I, the said George Lindsay, have hereunto set
my hand and seal, the 9th day of July, in the year of our Lord
One thousand eight hundred and seventy-two.
In the
presence
of
WILLIAM SOMERSET.
GEORGE LINDSAY. (L.S.)