IMPROVED MECHANISM FOR TRANSMITTING POWER
Year: 1871

page_text: LETTERS PATENT to Henry Graham Lawson, of 20, Budge Row,
Cannon Street, in the City of London, Seed Merchant, &c., for the
Invention of "IMPROVED MECHANISM FOR TRANSMITTING POWER."―A
communication from abroad by William F. Goodwin, of Metuchen,
'New Jersey, in the United States of America.
Scaled the 19th April 1872, and dated the 26th October 1871.
PROVISIONAL SPECIFICATION left by the said Henry Graham Lawson
at the Office of the Commissioners of Patents, with his Petition,
on the 26th October 1871.
I, HENRY GRAHAM LAWSON, of 20, Budge Row, Cannon Street, in
3 the City of London, Seed Merchant, &c., do hereby declare the nature
of the said Invention for "IMPROVED MECHANISM FOR TRANSMITTING POWER,"
a communication to me from abroad by William F. Goodwin, of Metuchen,
New Jersey, in the United States of America, to be as follows:-
This Invention relates to improvements in that mechanical combination
) or gearing in which a worm wheel causes a worm or screw to revolve
at a rate of speed greater than that of the worm wheel in the ratio that

page_text: the number of teeth in the wheel bears to unity. The working face of
the worm thread is bevelled at an obtuse angle with its tip, the bevel
being made equal to the pitch of the screw or nearly so, a corresponding
bevel being given to the inclined working faces of the teeth on the
wheel. The worm may be made of single or double thread. The working
faces of teeth and thread are so adjusted in their relative positions that
the teeth do not bear upon the thread until they are in full gear. The
teeth on that side of the wheel in the direction of lateral thrust on the
worm are made longer than on the opposite side of the wheel, so that
these ends of the teeth go deeper into gear and consequently are last to
go out of gear. The worm wheel and worm may be made of steel, cast
or wrought iron, or other suitable material. The worm may either be
cut on its shaft or made separately and fixed thereon. The worm and
wheel work in a closed case with removable cover fixed in any required
position, which case may be made of cast or wrought iron or other suit-
able material, bearings being formed in the top and bottom of the casc
for the wheel shaft and bearings at the side of the case tangentially to
the worm wheel for the worm shaft. That bearing of the worm shaft
which receives the end thrust caused by the driving wheel has a conical
pointed set screw on which the corresponding conically recessed end
of the worm shaft bears. The bearings for the worm shaft are made
removable to allow the worm to be passed into or withdrawn from the
case. The set screw receiving the end thrust of the worm shaft serves
also to adjust and maintain the relative positions of the working faces.
of the teeth of the wheel and the worm thread. The set screw may be
secured in its place by a lock nut or other suitable means. By this form
and construction of thread and teeth and their adjustment relative to
each other nearly all lateral thrust on the worm shaft is avoided, an
antifrictional bearing receives the end thrust of the same shaft, and
the whole working parts being in a closed case for the purpose of
excluding dust and providing for perfect lubrication, the friction in
working will be very much less than has hitherto been the case in the
working of mechanism of this description.
The power to be transmitted, whether steam, animal, or other power,
is applied by suitable means to the wheel shaft outside the closed case,
and is taken from the worm shaft also outside the said case as required
by the circumstances in which employed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Graham Lawson in the Great Seal Patcut
Office on the 26th April 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
GRAHAM LAWSON, of 20, Budge Row, Cannon Street, in the City of
London, Seed Merchant, &c., send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of October, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Henry Graham Lawson, Her special
licence that I, the said Henry Graham Lawson, my executors, adminis--
trators, and assigns, or such others as I, the said Henry Graham Lawson,
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 Islands, and Isle of Man, an Invention for
"IMPROVED MECHANISM FOR TRANSMITTING POWER," a communication to me
from abroad by William F. Goodwin, of Metuchen, New Jersey, in the
United States of America, upon the condition (amongst others) that I,
the said Henry Graham Lawson, my executors or administrators, 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.
>
NOW KNOW YE, that I, the said Henry Graham Lawson, do hereby,
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say:—
This Invention consists in a modification of the worm and wheel
gearing whereby the friction which has hitherto been the great loss of
power in such combinations is by this Invention brought to a minimum.
In order to make the Invention more readily understood, I will now,
refer to the annexed Drawings, in which Figure 1 is a perspective view
of the mechanism applied for transmission of horse or animal power;

page_text: Figure 2, a longitudinal sectional view; Fig. 3, a vertical section;
Fig. 4, view of the worm or worm shaft; Fig. 5, modification of
worm bearing and worm; Fig. 6, modified section of worm wheel;
Fig. 7, elevation of the worm wheel shown in Figure 6. In all the
Figures corresponding letters of reference are placed in corresponding
parts.
In constructing the mechanism the worm or screw F2 is made with
a thread or threads having the working face bevilled at an obtuse angle
with the tip of the thread, as shown in section in Figures 2 and 4, the
angle VIX, Figure 4, which the working face makes with the line IV
which is at right angles with the axis of the worm, being made equal
or nearly so to the angle of pitch of the screw VPX, Figure 5, in which
the line VP is at right angles with the axis of the worm and the line
PX shews the incline or pitch of the tip of the thread seen in elevation
as it crosses the said axis. The opposite face of the thread is cut in
square or nearly so to the axis, as shown in section, Figures 2 and 4.
A bevel corresponding to that on the working faces of the screw thread
or threads is given to the inclined working faces of the teeth on the
worm wheel H, Figure 2, so that the latter do not bear upon the worm
thread until they are in full gear. The direction of motion of worm
wheel is shown by the arrow in Figure 2. The worm thread F³ is shewn
right handed in the Figures, and of double thread. As the worm wheel
turns on its axis C it causes the worm to turn on its axis in the direction
of the arrow in Figure 3. The direction of lateral thrust by the wheel
on the worm is therefore towards the sido K of the worm; the ends of
the teeth of wheel on side K are made longer and go deeper into gear
than the ends of the teeth on side L where they are cut off to the bottom
of worm thread, or entirely done away with as shown in the modified
section of the wheel, Figure 6, thereby greatly reducing both the lateral
thrust on the worm shaft and the friction in working. The worm F³
and wheel H work in a closed case A, having removable cover B, a step
C¹ being formed in the bottom of case A to support the lower end of
shaft C to which is fixed the worm wheel H to support the upper end
of said shaft, a sleeve or tubular bearing B' is provided, being cast by
preference in the same piece with cap B; the wheel H may also be
made with longer boss or hub for a good bearing and to revolve upon
axis C, gearing into a sliding clutch fixed on same axis C in the usual
form of clutch gearing, which arrangement permits of the worm and

page_text: At the
screw being readily thrown out of gear with the motive power.
side of the case a recess or chamber E is formed to take the worm, and
at each end of the recess are bearings E¹, E', for the worm shaft arranged
tangentially to the worm wheel H. The end thrust of the worm shaft is
against the bearing E³, into which is screwed a set screw e², having a
conical point at ƒ on which the end of worm shaft F conically recessed
bears, thus forming an antifrictional pivotal bearing for the said shaft.
The set screw is secured in its place by lock nut e³. By means of the
set screw e¹ the working faces of the wheel and worm may be adjusted
relatively to cach other as the parts wear. The bearing E', Figure 2,
is made removablo, being secured in its place by a pin c or its equivalent.
The bearing E may also be made removable so as to admit of the worm
being passed into the case from that side, and may be secured in like
manner to bearing E', Figure 2, or of itself screwed into casing A and
placing the set screw E' in it as shown in Figure 5. The end of worm
spindle at E³ may also be made of same diameter as worm screw with
recess to receive the point of set screw e', as also shown in Figure 5;
the point of set screw e¹ may either in this case be made conical or flat as
suitable. The case A has a rim A' closely surrounding the worm wheel
H provided with lugs a and perforations A'. The cover B is circular in
general outline, fitting closely on the rim A' provided with perforated cars
6 which correspond with lugs a, so that by means of bolts 6' the cap B
may be securely fixed to the body or case A; D, Figure 1, represents a
head or wheel attached to the upper end of shaft C and having mortices
d for the reception of arms to which horses are to be attached. G
represents a drum fixed on the worm shaft F, by means of which the
power given out by the mechanism may be transmitted as required.
Instead of drum G a crank or toothed wheel or other convenient
means may be employed for taking off the power.
Instead of animal power being employed to drive the mechanism,
steam or other power may be used by fixing on the shaft C a drum in
place of head or wheel D, or by any other convenient means.
Having now described and particularly ascertained the nature of the
Inventory, and the manner in which the same is or may be performed,
5 I wish it to be understood that I do not restrict or restrain myself to
the preciso details above described, as many variations may be made
therefrom without deviating from the main features of the Invention;
but what I consider novel and original and therefore claim as the In-

page_text: vention secured to me by the herein-before in part recited Letters
Patent is, in wheel and worm gearing in which the wheel drives the
worm.
1st. Forming the working face of the thread or threads of the worm
with a bevel at an obtuse angle with the tip of the thread, such bevel
being made equal to the incline or pitch of the screw in the manner
described in combination with a worm wheel, the tecth of which have
their working faces bevilled to correspond with the bevil on the thread
or threads of the screw, substantially as set forth.
2nd. In the worm wheel in combination with the inclined working 1
faces of the teeth making the teeth to go deeper into gear on that side
of the wheel which is in the direction of lateral thrust on the worm
shaft than on the opposite side of the wheel, as described.
(3rd.) The employment of an adjustable pivotal bearing to receive the
end thrust of the screw shaft, as described.
(4th.) In combination with the said wheel and worm the making of an
enclosing shell or casing provided with suitable bearings for the worm
wheel shaft and with chamber for the worm having removable bearing
or bearings for supporting the worm shaft, as described.
In witness whereof, I, the said Henry Graham Lawson, have here- 2
unto set my hand and seal, this Twenty-sixth day of April, in
the year of our Lord One thousand eight hundred and seventy-
two.
H. GRAHAM LAWSON. (L.S.)