Improvements in and relating to Variable Speed Gearing.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Variable Speed Gearing.
I, JAMES KENNEDY, of 25, Elmbank Street, in the County of the City of
Glasgow, Confectioner, do hereby declare the nature of my invention to be as
follows:-
This invention has reference to improvements in and relating to variable
speed gearing specially suitable for autocars, marine launches, and the like.
According to my improvements, I produce a driving gear embracing three
degrees of variable speed, a fast speed, a slow speed, and an intermediate speed.
In carrying these improvements into effect, I key or secure a disc or boss with
more but preferably
radial arms on a counter or other shaft, and I fit one or
three projecting pins or spindles on this disc which each carry a spur or toothed
pinion, and these pinions each gear into a central toothed wheel mounted loosely
on the aforesaid driving shaft and also gear with, the internal teeth formed on
the inner surface of the rim of an annular or outer wheel mounted loosely round
an extended sleeve formed on boss of central toothed wheel, or this annular wheel
may be mounted loose on shaft on opposite side of disc to that of the central
wheel. The central wheel which has the sleeve round shaft, has a broad disc
keyed on or formed round it at opposite end to the toothed part, and this disc
has its outer circumference formed both as a sprocket or toothed wheel at one
part and as a brake sheave at its other part; while the outer or annular wheel has
sprocket teeth formed on its outer circumference and a brake sheave formed on
another part of said wheel, the part on which the brake sheave is formed prefer-
ably extending solidly inwards to sleeve of central wheel. Straps would be
mounted round the brake sheaves of each of these wheels, and be connected to
the opposite ends of a hand operated lever, so that by oscillating the handle of
said lever, either of these brakes can be put on, and the other off, or both can be
freed according to the speed to be transmitted.
The sprocket or spur teeth of the central and annular wheels would each gear
either direct or through intermediate wheels, with the teeth of two wheels mounted
loosely on the axle or other shaft to which the power is to be transmitted.
Projecting pins or spindles would extend from the inner parts of these latter
wheels and have each mounted on them two or more pawls, one set for driving
forward and the other for driving backward the axle or shaft which would have
a ratchet or like toothed wheel keyed to it at the part opposite these pawls or
these pawls may be mounted on separate pins.
A projecting circumferential part would extend radially towards each other
from each of the sprocket wheels, and within same would be mounted a moveable
clutch with two inwardly projecting surfaces which when operated by a hand
lever would bear on the arms of, and keep the pawls of the forward and back-
ward motions of both wheels respectively out of gear with the ratchet wheel,
according to the direction of rotative shaft motion required, or keep all the pawls
or when desired.

page_text: For reversing the car, a clutch would be fitted on the counter shaft, which
would be disengaged from shaft and engage with driving wheel and with the
annular or central wheel before mentioned, and a strap or like brake would be
fitted to operate on counter shaft.
With this arrangement of mechanism wwhen a slow speed was desired, both
brake straps would be left loose, and both the central and outer annular wheels
would transmit the. motion given by the pinions mounted on the spindles of the
disc keyed to the primary shaft, by the toothed gearing to the loose disc so that
the latter would both be actuated together and transmit their motion to the
ratchet wheel on axle or driven shaft.
When a fast speed or an intermediatory speed between, this and the slow speed
was desired, the brake lever would be operated and the brake strap tightly applied
to one of the brake sheaves, while the brake strap of the wheel which is to
convey its motion would be loose, and this wheel would through the toothed
gearing transmit motion to one of the loose wheels and through it to the ratchet
wheel on the secondary or driven shaft.
Friction clutches would or may be mounted on the secondary shaft to gear with
the bosses of each of the loose wheels when starting the motion of shaft, and ball
bearings may be mounted in the bosses of the wheels.
Instead of toothed wheels, the wheels may be formed with friction driving
surfaces.
Dated the 29th day of September 1897.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.
Improvements in and relating to Variable Speed Gearing.
I, JAMES KENNEDY, of 25, Elmbank Street, in the County of the City of
Glasgow, Confectioner, do hereby declare the nature of my invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement, that is to say: -
This invention has reference to improvements in and relating to variable
speed gearing specially suitable for autocars, marine launches, and the like.
According to my improvements I produce a driving gear embracing three
degrees of variable speed, a fast speed, à slow speed, and an intermediate speed.
And in order that my said invention and the manner of carrying same into
practice may be properly understood I have hereunto appended a sheet of ex-
planatory drawings in which Figure 1 is a plan view showing my improved
variable speed gearing. Figure 2 is a sectional elevation as taken on
line 2-2 of Figure 1. Figure 3 is a sectional elevation of the epicyclic gear
and brake discs, and Figure 4 a section as taken on the line 4-4 of Figure 3,
Figure 5 is a cross and longitudinal section showing the mechanism for actuating
the pawls, and Figure 6 is a plan and cross section showing clutch arrangement
for actuating the sprocket wheels on driven shaft.
Referring to these drawings:-
the
In carrying these improvements into effect I key or secure a disc or boss A with
arms on a counter or other shaft A' and I fit one or more but preferably three project-
ing pins or spindles a on this disc A which each carry a spur or toothed pinion a¹
and these pinions each gear into a central toothed wheel a² mounted loosely
on the aforesaid driving shaft A¹ and also gear with the internal teeth formed on
the inner surface of the rim of an annular or outer wheel mounted loose on

page_text: shaft A' on opposite side of disc to that of the central wheel or it may be mounted
loose round an extended sleeve on boss of central wheel. The central wheel a²
has a broad annular disc a³ keyed on or formed round it at opposite end to the
toothed part, and this disc a³ has a sprocket or toothed wheel formed on or fitted
to one part a and formed as a brake sheave at its other part a5 and it also has a
half friction or gab clutch H³, while the outer or annular wheel b has a sprocket
wheel formed or fitted at one part, and a brake sheave 6 formed on another
part of said wheel, the part on which the brake sheave is formed preferably ex-
tending solidly inwards to sleeve of disc A. Straps B would be mounted round
the brake sheaves of each of these wheels, and be connected to the opposite ends
of a bell crank lever B¹ mounted on a spindle B2 and operated by a hand lever B
so that by oscillating the hand lever either of these brakes can be put on, and the
other off, or in their mid position both can be free, according to the speed to be
transmitted.
The sprocket or spur teeth a' and 6 of the central and annular wheels a and b₁
would each gear either direct or through intermediate wheels, with the teeth of
two wheels C and C¹ mounted loosely on the axle C2 or other shaft to which the
power is to be transmitted.
Projecting pins or spindles c would extend from the inner or outer parts of
these latter wheels and have each mounted on them one or more pawls c¹, one
set for driving forward on wheel C which gears with the wheel a', and one set for driv-
ing forward, and another set for driving backwards on wheel C which gears with
the wheel b, for the purpose of driving the axle or shaft C which would have
three ratchet or like toothed wheels mounted on a sleeve on it at the part
opposite these pawls, or these pawls may be mounted on separate pins. Two sets
of these pawls will have raised tails, that is the forward set for the wheel C and
the backward set for the wheel C₁ which will be operated by a cylindrical band
or internally conical piece z which may go over and depress the tails of pawls
on either side as desired and thereby raise the teeth of same out of contact with
their corresponding ratchet wheels or in mid position will be over and depress
the tails of both sets, and thereby raise the forward pawls on C, and the back-
ward pawls on C₁ if desired. This band z will be mounted loosely on the sleeve c³
and have a groove on outer surface which will be operated by a forked lever.
Instead of the cylindrical band with internal conical surface for depressing the
tails of the pawls a band with conical external surfaces of less diameter, mounted
in the same manner, could be operated similarly to act on the under side of the
tails to raise the points of the pawls for the purpose above described. Instead
of the above with reference to Figure 6 claw or gab clutches and could be
cast or fixed to the sides of wheels C and C₁ respectively, which would engage
with their counterparts mounted loosely on a feather f on axle C2 so that
the counterpart could engage with the half clutch k on C, or the part with
the half clutch on C¹, or in mid position both the parts and would engage
with and respectively, and these counterparts and would be operated by
a forked lever.
For driving forward a half gab or friction clutch H will be keyed or fixed to
the counter shaft A¹, and this will also have a brake sheave D2 fixed to or cast
with it with a brake band for causing a backward drive.
With this arrangement of mechanism when a slow forward speed was desired,
the wheel I would be caused to engage the clutch H H and thereby drive the
O counter shaft A' in the same direction as D¹, both brake straps B would be left
loose, and both the central and outer annular wheels a³ and b would transmit
the motion given by the pinions a' mounted on the spindles of the disc A keyed
to the primary shaft A¹ by the toothed gearing to the wheels a and b¹ so that
these wheels would both be actuated together and transmit their motion to the
5 wheels C and C on axle or driven shaft C in which case the forward pawls C
and C would be allowed to engage but the backward set raised, or in the case
of the clutches shown on Figure 6 the counter parts and would be in mid

page_text: position and therefore engage in both wheels C and C¹. When a fast or inter-
mediatory speed between this and the slow speed was desired, the brake lever
would be operated and the brake strap tightly applied to one of the brake sheaves
while the brake strap of the wheel which is to convey its motion would be loose,
and this wheel would through the toothed gearing transmit motion to one of
the loose wheels C or C and through it to the ratchet wheel on the secondary
shaft C. The backward set of pawls on C¹ would at this time also be raised, or
in the case of the clutches the counter part and would be caused to engage
only with the wheel C or C which was being driven.
When the axle C is required to be driven in an opposite direction, the wheel D¹
will be moved towards the wheel at until the clutch H2 H3 is connected, and
the forward pawls on the wheel C will be lifted, and by applying the brake to
the brake sheave D2 the sprocket or toothed wheel b¹ will be caused to reverse
and convey the same motion to the shaft C by the backward pawls on the
wheels C. In the case of the clutches the counter part will be caused to
engage with on C¹. If the axle C is desired to be held or braked this can
be done in the case of the ratchets by applying the brake on b, and allowing
the backward pawls to be free, or in the case of the clutches by putting the
counter part and in mid position and applying any band D3 or B B. Or
when going backward by freeing brake band 12 and applying brake on b, with-
out altering the ratchets or clutches. When the wheel D is in mid position
the motor may run free and the gear and driven axle be at rest.
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:-
First. A driving gear embracing three degrees of variable speed constructed
and arranged substantially as herein described in reference to and shown in the
accompanying drawings.
Second. In variable speed gearing, the arrangement of discs a³ and b with
external and internal teeth respectively formed on same, in combination with
the disc A and spur pinion a', substantially as and for the purposes described.
Third. In variable speed gearing the arrangement of reversing clutch gear
substantially as set forth.
Dated the 29th day of June 1898
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.