Improved Differential Speed Gearing for, Bicycles, Tricycles, Motor Vehicles, and the like
Year: 1896

page_text: Date of Application, 4th Dec., 1896
Complete Specification Left, 5th Aug., 1897-Accepted, 4th Dec., 1897
PROVISIONAL SPECIFICATION.
"Improved Differential Speed Gearing for, Bicycles, Tricycles, Motor
Vehicles, and the like."
I, ALFRED GEORGE MELIUISH, of 208 Choumert Road, Peckham, in the County
of Surrey. Engineer. do hereby declare the nature of this invention to be as
follows:-
The object of this invention is to construct a differential speed gear for uso
in connection with Bicycles, Tricycles, Motor Vehicles, or moving shafts of any
description, whereby the said Vehicles may be caused to travel at any desired
speed without disconnecting one part of the gear to another, such as when a
pinion is slid along to engage in various sized wheels, and moreover in such a
manner that any desired speed from, say, zero to a given maximum may be
obtained without jolt or shock.
Briefly described, the gear consists of a worm or bevil wheel which is rotated
by engagement with a worm or bevil wheel of the Motor or other driving
mechanism, upon one of the arms of said driving wheel are two bevil wheels of
comparatively small diameter, these being connected to each other by a sleeve,
so that they rotate together. The worm or bevil wheel thus equipped is mounted
loosely on the shaft to be governed in such a manner that one of the small bevil
wheels is geared to a similar or smaller wheel fixed upon the shaft to be
governed while the other small bevil wheel is in gear with a large bevil wheel
which is so arranged in combination with a clutch mechanism that it may either
remain stationary under the action of a brako to give increase of speed to the
shaft to be governed, or it may turn at the same speed as the worm or bevil
wheel, and by its clutch pull the shaft round at a much reduced speed. Any
desired ratio between these two extremes may be had by allowing the large
wheel to slip more or less as the case may be.
If desired, the brake mechanism may be dispensed with and a friction disc may
be caused to bear against the driving disc at varying distances from its centre of
rotation, while the outer edge of said disc, or it may be a supplementary one, is
in positive gear by teeth with the worm or bevil wheel before described, so that
although the ratio of movement is determined by friction the main power is trans-
ferred in a positive manner.
When worm wheels are used I prefer to make the teeth in such a manner
that they rotate on pivots, studs, or ball bearings to reduce frictional waste.
Dated this 2nd day of December 1896.
ALFRED GEORGE MELHUISH.

page_text: Improved Differential Speed Gearing for Bicycles, Tricycles Motor
Vehicles and the like.
I ALFRED GEORGE MELHUISHI of 20 Hinckley Road East Dulwich late of
208 Choumert Rd, Peckham, London Engineer, 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:-
This invention relates to differential speed gearing, and in order that the same may
be thoroughly understood I now append a drawing which when taken together
with the hereinafter following description will convey a clear idea of the scope
and usefulness of my said invention, the novelty of the various parts and their
utility.
The gearing may be made in an alternative form as indicated & referred to
with regard to figs 5 & 6. Figs 1-2-3 & 4 being side sectional view, face view
and detail views respectively of the gearing referred to & fully described in my
provisional specification.
Referring more particularly to Figs 1-2-3 & 4 it will be seen that the wheel A
is mounted loosely upon the axle 13 upon the ends of which are fixed the driving
wheels of the vehicle. Upon one or more of the arms C of the wheel A is or are
loosely mounted a sleeve or sleeves D, having a bevil wheel E and F affixed
thereto at each end, the wheel E being in gear with a crown wheel G, which is
carried in separate bearings, G, G, this being one of the importantant features
of my invention. The other bevil wheel F is geared with a bevil pinion F1 fixed
to the driving axle B. The axle of the crown wheel G is surrounded by a brake
band H suitably connected to a foot, or hand lever I, which when it is desired
to check the rotation of the wheel G can be depressed to cause the band to bite
upon the axle with more or less pressure as desired.
If
Another important feature is the employment of a ratchet wheel J and fixing
it to the axle B, and causing a pawl K carried by the axle of the crown wheel G
to gear therewith. The spindle or pivot L of said pawl K is carried through the
axle of the wheel G to the outside end M & terminates in an inclined tangential
lever N which can be operated to lift the pawl K out of contact with the ratchet
wheel J, by moving inwards under the action of a lever P an inclined sleeve Q,
which lifts the tangential lever, preferably against the tension of a spring not
shewn, but which when released will return the pawl K to the teeth of the wheel J.
The wheel A is driven in any suitable manner from a motor or pedal gear, either
by direct spur gear, chain or worm gearing. in the direction of the arrows.
the ratchet be held out of gear, the wheel A will rotate without transferring
motion to the axle B, because the crown wheel can freely rotate. When however
it is desired to proceed slowly and positively such as when going up hill or along
a crowded thoroughfare, the conical sleeve Q is withdrawn by the lever P when
the wheels A, E, F, G & F, become locked together and cannot rotate indepen-
dently, but rotate with the wheel A to drive the spindle or axle B, by the
engagement of the pawl K with the ratchet wheel J. When it is desired to drive
the axle B at its maximum rate of speed, then the brake band H by the lever L
is caused to bite upon and hold the axle of the wheel G and prevent same from,
rotating, which will cause the wheel E to rotate upon its spindle, & also the
wheel F, to rotate the pinion F1, at a much faster rate than is the case when
the axle is driven direct as before explained. by. means of the ratchet wheel and
pawl In order that there may be no shock or jar when gearing up from the
minimum to the maximum rate the wheel G may be caused to stop gradually,

page_text: by regulating the pressure of the brake band upon the axle B. By mounting
the axle of the wheel G in separate bearings and allowing the axle B to pass
freely through it, there is no retarding strain put upon said axle B tending to
put extra work upon the motor or pedals. when the brake is put on. which in
other devices of the kind renders them impracticable. And by the use of the ratchet
wheel and pawl, I am enabled to proceed long distances at a maximum of power
with a minimum of speed without putting on the brake to check the speed of the
wheel G, the said brake being only required when changing from one speed to
another, therefore resulting in economy of power as well as considerably lengthen-
ing the life of the brake band. which by other methods would become worn by
slow speeds.
I do not confine myself to the use of bevil wheels, as I prefer an epicyclio
train of gearing as depicted in Figs 5 & 6, the functions of each wheel being the
same as in Fig 1, corresponding parts being denoted by like letters, it being
understood that the brake & ratchet gear being used in each case.
Or the brake
may be in some cases dispensed with and an equivalent employed such as a
friction clutch or positive clutch, but preferably that form of clutch that will
allow of a gradual pressure being applied.
I may duplicate the arrangement shewn in Figs 1 & 5 by adding a crown
wheel on the opposite side, in which case there would be two brakes and the
vehicle be driven backwards, according to the Brake band that was operated
and if both brakes were used at the same time the vehicle could be retarded
such as when going down hill.
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.
(1) In differential speed gearing the combination with a gear wheel mounted
loosely upon the axle to be driven, of bevil wheels loosely mounted upon one or
more arms of said wheel, in gear with a crown wheel carried in separate bearings,
and a bevil pinion fixed to the axle to be driven, and providing the axle of said
crown wheel with a brake band attached to a suitable lever; and a pawl for
engagement with a ratchet wheel fixed to the axle to be driven; said pawl being
retained in the teeth of the ratchet wheel by a spring & lifted therefrom by a
lever and a conical sleeve, all arranged and constructed substantially as shewn,
& operated in the manner and for the purpotes described with reference to
Figs 1-2-3 & 4 of the annexed drawings.
(2.) In differential speed gearing the employment of an epicyclic train arranged
as shewn in Figs 5 & 6, and the combination therewith of a brake axle mounted
in separate bearings and a ratchet wheel & pawl, as set out in claim 1 & as
described.
3. In differential speed gearing employing a brake and brake axle, and gearing
so that the vehicle remains stationary when the drum revolves freely and is
moved when the braked wheel is retarded; mounting said brake axle & wheel
independently of the other parts of the gearing and in such manner that no
strain or retarding effect is imparted to the gear as shewn & described.
4. In differential speed gearing of the kind set out in claim 3, the employment
of a pawl carried by the braked wheel, and a ratchet wheel fixed to the axle to be
driven the one being made to gear with the other & lifted therefrom in the
manner and for the purpose described all the parts being arranged substantially
in the manner shewn..
100
ALFRED GEORGE MELHUISH.