Improvements in Speed Changing Gear for Cycles, and the like.
Year: 1898

page_text: Date of Application, 20th Dec., 1898-Accepted, 28th Jan., 1899
COMPLETE SPECIFICATION.
Improvements in Speed Changing Gear for Cycles, and the like.
I, FRED PEARLY SNOW, of 15, Rockingham Street, in the City of Lynn, County of
Essex, in the State of Massachusetts, United States of America, Inventor, 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 :-
My invention relates to that class of gearing for bicycles, and other like vehicles,
by which the wheel is driven, at the pleasure of the rider, either at one or the other
of two predetermined rates of speed, relative to the rate of pedalling.
My object is to produce a good, practical, two-speed gear of this kind, compact and
not liable to get out of order. To accomplish this object I place in the hub of the
driving-wheel a gear-wheel which is united with the sprocket-wheel, a gear-wheel
which is locked to the sprocket-wheel and to the bicycle frame alternately, and a
gyratory pinion, which engages the gear-wheels, and is mounted upon a spider to
which the shell of the hub is made fast. The operation of the invention is such that
the driving-wheel to which it is applied may itself be driven either in unison with the
sprocket-wheel or in unison with such pinion-carrying spider, according to the
changing conditions of travel or the pleasure of the cyclist.
In the accompanying drawings I have shewn how my invention may be carried into
practice.
Figure 1 is a side view of a portion of a bicycle, and includes an end view of the
hub of the driving-wheel, all constructed in accordance with the requirements of my
invention.
Figure 2 is an axial section of Figure 1.
Figure 3 is a cross section of the hub, on line xx of Figure 2, and viewed in the
direction of the arrows in that figure and
Figure 4 is a like section of the hub on line y-y of Figure 2.
In these views the numeral 1 denotes the axle of the driving-wheel to which my
invention is applied. This axle is stationary, being part of the bicycle frame 2, or
rigidly attached to that frame, as indicated in Figure 1. On this axle is a rotary
sleeve 3, which is provided with a flange 4 and with a bevelled gear-wheel 5, the
latter being fixed stationarily upon the sleeve by means of checknut 18, as shown in
Figure 2. A similar gear-wheel 7 and the sprocket-wheel 6, which are either con-
nected rigidly with each other or are preferably united in one piece, are placed
rotatably upon the same sleeve. Between these gear-wheels is a rotatable spider 8,
upon which is journalled a pinion, or a pair of pinions, 9, duplicates of each other,
engaging the gear-wheels continually, and held down to their work by collars 31. The
external shell 10 of the hub is made fast to this spider by screws 11, and is provided
with an annular head 16, to which it is made fast by screws 17. Sleeve 3 is held in
position upon the axle by nuts 12 and 13 and by intermediate ball bearings 14 and 15.
In like
The same ball bearing 14 facilitates the rotation of the annular gear 16.
manner a duplex ball bearing 19 permits free rotation of spider 8 relatively to
the gear-wheels, and of the gear-wheels relatively to each other; while a ball-

page_text: bearing 20 reduces friction between the flanged shell or sleeve 3 and the
sprocket-wheel 6.
On the inner face of flange 4 are placed pawls 21, which are provided with
engagement springs 22, as shown in Figure 4, and are adapted to engage sprocket-
wheel 6 by means of notches 23 on the hub of that wheel. Pawls 21 are also provided
with pins 33, extending through slots 32 in flange 4: while on the outer face of the
same flange, as seen in Figure 1, is seated an annular cam 24, engaging said pawls
by means of said pins 33, and held to its seat by the heads 34 of said pins. For
locking purposes flange 4 and cam 24 are provided with peripheral notches 25
and 26, which are shown in full lines in Figures 4 and 1 respectively; while a
dog 28, having a tooth 29, adapted to enter those notches is pivoted to a hanger 27,
depending from axle 1. In order that dog 28 may be made to engage and to
disengage the flange 4 and the cam 24, some suitable mechanism for actuating
the dog, although not shown in the drawings, is connected with that dog by
rod 30, and is arranged within easy reach of the rider. It is to be understood
that the spokes of the driving-wheel, though not shown in the drawings, are attached
to shell 10 in some usual or convenient manner.
Such being the construction of my improved two-speed gear, its mode of operation
is simple and obvious. When dog 28 occupies a position of disengagement, as
shown in the drawings, the pawls 21, being actuated solely by springs 22, engage 1
the sprocket-wheel 6 by means of notches 23, as shown in Figure 4; then the
sprocket-wheel, being locked to flange 4, and so imparting its own rate of rotation to
sleeve 3, drives the hub in unison with itself. But whenever dog 28 is raised to its
position of engagement, not shown in the drawings, cam 24 is stopped by the
entering of tooth 29 into notch 26. By the consequent. raising of pawls 21 out of
notches 23, the described engagement between sprocket-wheel 6 and sleeve 3 is
released, while by the entrance of tooth 29 into one of the notches 25 on the
periphery of flange 4 the rotation of that sleeve is stopped. The consequent
rotation of the driving gear-wheel 7, relatively to the stationary gear-wheel 5,
imparts to pinion 9, which rolls between them, not only a rotary motion about
its own axis, but also an orbital motion around sleeve 3. By virtue of this orbital
motion, which is transmitted to shell 10 through spider 8, the hub is driven in
unison with the pinion, and the driving-wheel of the bicycle is revolved with an
angular velocity equal to one half that of the sprocket-wheel. So by the mere
manipulation of the mechanism that actuates dog 28 the rider of the bicycle is enabled
by this invention to impart to the driving-wheel of his vehicle either the full rate
of rotation of the sprocket-wheel or one half of that rate, as he may please, or as the
conditions of travel may require. This mode of operation presents the important
advantage that the gears are brought into operation only when the speed is reduced,
and consequently the friction is least when the speed is greatest.
The essence of the invention does not lie in the number of the gyratory pinions 9,
for the mode of operation would be the same, if the number of those duplicate
pinions should be increased or diminished; nor in the cogs that are cut upon
the gear-wheels and pinions, for obviously the same engagements might be effected
between them by other equivalent frictional mechanism.
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 :-
1. A stationary axle, "a sleeve and a gear-wheel, which are connected to rotate in
unison on said axle, a sprocket-wheel and a gear-wheel, which are connected to
rotate in unison on said sleeve, a rotary spider on said sleeve, and a pinion, which is
journalled on said spider, and continually engages both said gear-wheels, in com-
bination with a hub shell, which is made fast to the spider, and alternate locking
mechanism, whereby all the rotary parts of the hub may be fastened to revolve in
unison, and whereby the first-mentioned gear-wheel may be fastened so as not to
rotate at all, substantially as and for the purpose specified.

page_text: 2. In the driving-wheel of a bicycle or other like vehicles, an axle that is made
fast to the frame of such vehicle a sleeve which is rotatable on that axle, a sprocket-
wheel and a gear-wheel, which are united with each other, and are rotatable on said
sleeve, a stationary gear-wheel on said sleeve, a spider that is rotatable on said sleeve,
and a pinion, journalled on said spider, and continually engaging said gear-wheels,
in combination with a rotary cylindrical shell, made fast to said spider, and mechanism
for locking said sleeve alternately to the sprocket-wheel and to the frame of the
vehicle, substantially as and for the purpose specified.
3. A stationary axle, a rotary sleeve thereon, a sprocket-wheel and a gear-wheel,
connected to rotate in unison on said sleeve, a stationary gear-wheel on the same
sleeve, a spider that is rotatable on said sleeve, a pinion, journalled on said spider,
and engaging both said gear-wheels, a rotary shell, made fast to said spider, a
notched flange on said sleeve, and one or more pawls, mounted on said flange, and
adapted to engage the sprocket-wheel, in combination with a notched cam,
actuating said pawls, and a dog to catch said flange and said cam, substantially
as and for the purpose specified.
4. A stationary axle, a sleeve and gear-wheel, which are connected to rotate in
unison on said axle, a sprocket-wheel and a gear-wheel, which are connected to
rotate in unison on said sleeve, a pinion, which meshes continually with both
said gear-wheels, and a hub shell, to which the journal of said pinion is made
fast, in combination with alternate locking mechanism, substantially as and for
the purpose specified.
•
Dated this 20th day of December 1898.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.