Improvements in Driving Gear for Cycles.
Year: 1897

page_text: Improvements in Driving Gear for Cycles.
I, CHARLES ERNEST BAXTER, of 240, New Spring Street, Brookfields, in the
City of Birmingham, Clerk, do hereby declare the nature of this invention to be
as follows:-
This invention has for its object, improved means whereby a cyclist may readily,
and preferably without dismounting, alter his driving gear so as to vary the
relative speeds of the driving axle and rear or driven wheel, in order that when
running uphill or against a strong wind he may be able to propel the machine
under more advantageous conditions than if the relative speeds of such axle and
wheel remained the same as in ordinary running.
The motion of the driving axle is conveyed to the rear wheel, according to this
invention, by means of one or other of two longitudinal spindles which are used
in lieu of the chain commonly employed for the purpose. Two toothed wheels
are fixed upon the driving axle, and two toothed wheels are formed with the rear
wheel hub or are rigidly connected with such wheel and have a common axis
therewith. Each longitudinal spindle has a toothed wheel fixed thereon at cach
end, and each spindle is capable of being moved endways. One of these spindles
may be moved into position endways to bring the wheel on its forward end into
gear with one of the wheels of the driving axle and at the same time bring the
wheel on its other end into gear with one of the toothed wheels of the rear wheel;
and the other of these spindles may be correspondingly moved to bring its wheels
into gear, respectively, with the other wheel of the driving axle and with the other
toothed wheel of the rear wheel. The means of moving these spindles are such,
however, that one spindle is first moved out of gear with the driving axle and rear
wheel before the other spindle is moved into gear therewith, and vice versa; and,
of course, if desired both spindles may be moved into position out of gear with
the driving axle and rear wheel. These means may consist conveniently of
forward bearings which are situated within a chamber which forms a rearward
extension of the bottom bracket and are capable of sliding endways within suit-
ably-shaped portions of such chamber, of right and left hand screws which are
screwed, respectively, through lugs of such bearings, and of light bevel gear and
spindles by means of which the two screws may be rotated in the same direction
from a handle situated immediately to the rear of the right side of the upper
portion of the steering socket, or in other position convenient for manipulation
by the rider. The longitudinal spindles are thus moved endways in opposite
directions to one another by moving their forward bearings, and they may either
slide endways through their rear bearings, or such, also, may be adapted to slide
endways in the framing. The toothed wheels through which the motion of the
driving axle is transmitted, by means of one of the longitudinal spindles, to the
rear wheel, are of course proportioned to give a different relative velocity between
such axle and wheel, to that which is given when driving by means of the other

page_text: longitudinal spindle; and this may be effected by simply making the two wheels
of the driving axle of different diameters.
The two longitudinal spindles may, pass, respectively, through the two tubular
back stays; and in such case, and preferably also even if the spindles are not
carried through such stays, the bottom bracket is adapted as to size and shape
for the wheels of the driving axle and the forward wheels of the spindles to work
therein, and also to hold a bath of oil within which such wheels work.
The toothed wheels through which the motion of the driving axle is transmitted
to the rear wheel may be bevel wheels, or the teeth of the driving wheel of each
pair may project sideways into the spaces between the teeth of the driven wheel,
and the teeth of such latter wheel be bevelled off or shaped towards the side at
which the teeth of the other wheel of the pair enter between them.
Dated this 3rd day of December 1897.
I, CHARLES ERNEST BAXTER, of 240, New Spring Street, Brookfields, Birming-
ham, in the County of Warwick, Clerk, 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:-
06
"
This invention relates to driving gear for propelling cycles of the "chainless"
type by which a two speed
gear is obtained in a very simple and effective
manner. Moreover by my particular construction of gear an adjustment of the
gear wheels with respect to one another can be easily effected so that all rattling
and backleash between the same is avoided, and the arrangement of the driving
wheels on the driving shaft is such that they lie centrally between the bearings
in the bottom bracket of the cycle, equal pressure and wear and sweeter running.
of the cycle being thus obtained. The arrangement of the gear on the driven
shafts is also such that it tends to "expand" in the same, direction at each end-
(the points of contact being all in line) thus ensuring the absence of cross strains
being set up in the machine's structure, and the main working parts of the gear
are such that can be neatly boxed in and hidden from view.
My improved driving gear is operated from the bottom bracket spindle of the
cycle in the ordinary manner. by pedalling by means of two driving wheels (of
unequal diameter) fixed and keyed on the said bottom bracket's spindle at. equal
distances from each other and the bracket's bearings. These driving wheels,
which are preferably bevelled, gear into two smaller bevelled wheels, which are
attached to shafts running along each side of the cycle, and are encased in the
chain. stays thereof, and which drive the cycle's back wheel by means of gear
wheels on their other and latter ends gearing into and.driving larger gear wheels
attached to the said rear wheel's axis.
Centrally situated within the framing in the bottom bracket of the cycle so
as to revolve therein are two small shafts or pins which are respectively screwed
in a right and left handed direction along their length. These externally screwed
shafts are mounted. to revolve within the bracket's framing, and are each fitted
with like internally screwed sleeves which have a horizontal travel upon them.
These differentially and internally screwed sleeves are each provided with a tooth-

page_text: like projection or lug on their outer side for the purpose of taking into and form-
ing, with coned-like parts fixedly attached to each of the driven shafts running
on each side of the cycle, bearings for the said shafts to rotate in. These pro-
jecting tooth-shaped portions or lugs lie clear of the rotating driven shafts holes
being bored in them for the shafts to rotate in, but they form ball races with the
coned-like parts of the bearings for anti-friction balls to rotate therein, so that
the said projecting teeth touch the balls on either side. The differentially-
screwed shafts carrying their screwed sleeves are rotated or put into motion by
means of a bevelled gear wheel disposed on a horizontal shaft genring into two
smaller bevelled wheels fixedly attached to their forward ends, and this bevelled
wheel is in turn driven by further gear wheels attached to vertical and diagonal
shafting from a toothed annulus gear wheel situated under. the lug connecting the
horizontal framing bar of the cycle to its front framing member or pillar. This
toothed annulus gear wheel is operated by hand by the cyclist when he or she
requires a higher or a lower gear, by turning the wheel in the one or the other
direction. The motion being transmitted through the various shafts. and gear
wheels to the horizontally disposed and differentially screwed pins which, in turn,
transmit the motion to their externally screwed sleeves and which latter, by
means of their projecting-tooth-like portions taking into the bearings on each side
of the driven shafts move the gear wheels attached to the latter into and out of
contact with the driving wheels; the driven shafts being supported in bearings
atieither end of the cycle for this purpose.
In the accompanying sheet of drawings Fig. 1: shows a plan of my improved
gear, Fig. 2 a sectional elevation thereof; and Fig. 3 a view of the upper part of
a cycle's framing fitted with my improved gear showing the means for operating
the two-speed gear from the cyclist's riding position on the machine.
The same letters of reference indicate corresponding parts in all the figures in
the-sheet of drawings.
The bottom bracket spindle a of the cycle runs in the ordinary bearings a³, a³,
and has fixedly connected upon it at equal distances from its bearings two driving
wheels of unequal diameter 61, 62. These driving wheels are driven by cranks c, c³,
in the ordinary manner by pedalling. These two driving wheels b₁; 62; gear or
mesh into smaller gear wheels d, da; fixedly connected to the ends of two hollow
shafts d, d, running along each side of the cycle's framing and encased and
hidden from view in the chain stays d¹³, d; thereof: These hollow shafts are
mounted in suitable bearings do, do, at the rear end of the cycle's framing and
also at their front ends by adjustable bearings do, do, and drive the cycle's rear
wheel by means of gear wheels ³, d¹, engaging and driving gear wheels e, c²,
situated on the back wheel's hub e³.
Centrally situated within a suitable framing f within the cycle's bottom
bracket at and mounted so as to rotate therein are two externally and differen-
tially screwed shafts or pins s¹, s2, secured by nuts n, n², to the framing fat
their inner ends, and having small gear wheels ³, 84, fixedly connected to their
other ends, for the purpose of engaging with a large gear wheel so fixedly mounted
upon a horizontal hollow shaft 9 rotating in the bracket's framing f. Mounted
to rotate and travel horizontally upon the externally and differentially screwed
shafts or pins s¹² are two internally screwed sleeves p¹, p², having tooth-like
projections or lugs 3 in one with their outer sides. These tooth-like pro-
jections. p, p, take, in conjunction with similar tooth-like projections p1, p18
working or travelling in slides 713 situated within the framing f, into and form
bearings with coned parts p5, 26, for the driven hollow shafts a, as, to rotate in.
The coned-like parts p, p, are fixedly connected to rotate upon the said driven
hollow shafts, and their inner coned surfaces 78 form with the coned-like
portions p10 of the tooth-like projections 73, 74, ball races wherein anti-friction
balls rotate, so that, when the screwed sleeves 71, 72, are rotated on their shafts
or pins s¹, s. they move, by means of their tooth-like projections ³, 11,
and p the gear wheels d', d², into or out of gear with their respective driving

page_text: shafts 61 62 a two speed gear being thus obtained. It should be understood that
the tooth-like projections or lugs are formed out of the one piece of metal, a hole
being bored in the middle for the driven shaft to take into.
The large gear wheel 5, situated upon the hollow shaft g in the bottom part
of the framing f, is driven by means of a small gear wheel so meshing into a gear
wheels on a vertical hollow shaft 2 also situated within the framing f. This
vertical hollow shaft g² is, in turn, driven by its gear wheel 8 engaging with a
gear wheel attached to the diagonal hollow shaft g³. This hollow shaft rotates
within the diagonal hollow framing member of the cycle, the said hollow
shaft being suitably mounted within the same. A further hollow shaft g
running parallel with the front framing member of the cycle, 2, drives this
diagonal hollow shaft g³ by means of its gear wheel sl engaging with the gear
wheels on the said diagonal shaft; the said hollow shaft g being let into the
lug of the cycle's framing for that purpose. Situated within reach of the
cyclist, at one side of the lug 4 connecting the horizontal framing member v5 of
the cycle with its front framing member 2, is a small toothed annulus turn or
wheel g', which is turned in the one or the other direction by the cyclist when
he or she desires to change the gear; the inner toothed face g6 of the turn or
wheel engaging with a small wheel s¹ on the hollow shaft g. This hollow
shaft and its gear wheels s¹1 512 may, if desired, work within the front framing
member 6 of the cycle.
It will be observed that an adjustment of the driving wheels 61 62 on the
bracket's spindle a and the driven wheels d¹, d, on the hollow shafts d', ds, with
respect to one another, so as to get a good surface contact and obviate all rattling
and back-leash, can be easily and simply effected by traversing one of the screwed
sleeves on the differentially screwed shafts or pins in a forward direction.
Access to the gear is had by means of a lid h, the same being connected to
the bracket's framing f by screws h². Wherever possible I construct the driving
and driven shafts hollow for the sake of lightness, and bevelled wheels are pre-
ferably used for transmitting the motion, although I may use toothed wheels of
any particular construction.
"
The means described for adjusting the hollow driven shafts in a longitudinal
direction (either the one way or the other) will be found of distinct advantage
in a single
chainless gear for effecting an easy adjustment of the driving and
driven wheels with respect to each other, and the same may be arranged in
any suitable position within the machine's framing.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
"
First. In "chainless" driving gear for cycles, characterised by a "two-speed
gear, the combination with the cycle's bottom bracket axis of driving wheels
of unequal size fixedly mounted thereon, hollow and longitudinally adjustable
driven shafts supported within suitable bearings at each of their ends and com-
municating motion to the rear wheel of the cycle by means of gear wheels disposed
at their respective ends, tooth-like projections taking into and constituting, with
fixed cone-like parts, adjustable bearings for the said driven shafts, screwed
sleeves for giving the said tooth-like parts a horizontal traversing movement within
the said bearings, differentially screwed shafts or pins for rotating the said sleeves
in a forward or backward direction, and the means for rotating the said differen-
tially and externally screwed shafts or pins from the head of the cycle,
substantially as and for the purpose described and set forth.
"
chainless gear for cycles characterised by a
<
Second. In C
the combination with the bottom bracket's framing of externally and differen-
two-speed" gear,
tially screwed shafts or pins s¹, 2, lying centrally and mounted to rotate therein,
internally screwed sleeves p¹, på, horizontally traversing the said shafts or pins,

page_text: projections or lugs p³, 2 on their outer sides for the longitudinal adjustment, with
corresponding projections 21, 212, working or travelling to and fro in slides p13
in the framing f, of the hollow shafts d, d, running through the said bottom
bracket's framing, substantially as described and set forth.
66
Third. In "chainless" driving gear for cycles characterised by a two-speed
gear the, mounting of the hollow shafts d', d8, in bearings do, do, so that the said
shafts are capable of a longitudinal adjustment in one or the other direction, sub-
stantially as and for the purpose described and set forth.
66
"
Fourth. In "chainless gear for cycles characterised by a two-speed gear,
the combination of cone-like parts 25, 26, having coned faces 17, 18, with tooth-
like projections 23, 24, to form an adjustable longitudinal bearing for the hollow
shafts d, d, and to give them a longitudinal adjustment in either the one or the
other direction, substantially as described and set forth.
Fifth. In "chainless" driving gear for cycles characterised by a
""
two-speed'
gear the means for operating and changing the gear from the cycle's head, sub-
stantially as described and set forth.
Sixth. In "
chainless" gear for cycles, the means for longitudinally adjusting
the hollow driven shafts in one or the other direction, consisting of screwed
sleeves,, traversed in a to and fro direction by screwed pins or shafts s', s2,
operated from the head of the cycle's framing, which said screwed sleeves have
projections or lugs p, p, engaging with fixed rotating parts 25, 26, on the hollow
driven shafts d', ds, and which constitute both a bearing for the shaft and a means
for effecting its easy adjustment in one direction or the other, substantially as
described and set forth.
<<
Seventh. In "chainless" driving gear for cycles characterised by a two-
speel" gear, the general arrangement, combination, and fitting of the parts,
substantially as described and set forth.
Dated this 5th day of September 1898.
W. P. THOMPSON Co.,
11, Burlington Chambers, New Street, Birmingham,
Also of Liverpool, Londoz and Manchester,
Patent Agents for the Applicant.