Improvements in and relating to Chain Gear for Velocipedes and other purposes.
Year: 1896

page_text: Date of Application, 17th June, 1896
Complete Specification Left. 17th Apr.. 1897-Accepted. 12th June, 1897
PROVISIONAL SPECIFICATION.
Improvements in and relating to Chain Gear for Velocipedes and
other purposes.
I, TIMOTHY SHEPHERD, of Kenilworth, Oakfield Road, Birmingham, in the
County of Warwick, Engineer, do hereby declare the nature of this invention to
be as follows:-
My invention is designed to minimise the friction between the gear wheels and
the chain through which power is transmitted; to obtain a direct strain from one
wheel to another from the most suitable point, without having the driving strain
upon any of the links of the chain that are in motion out of the straight line as
for example in wrapping around the gear wheel; to provide means whereby a
number of gear wheels may be driven simultaneously with one chain; to enable
any of the said wheels to be taken out of gear without unfastening the links of the
chain; to enable driving and driven gear wheels of varying sizes to be employed
without variation of length of chain required; to arrange the chain in such a
manner that it can readily and cheaply be covered with a case to protect it from
grit and dust, and generally to effect the improvements hereinafter indicated.
In carrying my invention into practice I make the chain to pass around
drums or rollers instead of around the driving and driven wheels. These drums
or rollers I place immediately above, or otherwise in close proximity to, the driving
and driven gear wheels in such a manner that the chain will gear with the teeth
of the latter. These rollers may be plain on their peripheries or they may have
teeth or flanges and may be mounted on ball, roller, or plain bearings on a suitable
support near to the driving and driven wheels in such a way that the distance
between the roller and the said wheels may be regulated and adjusted both
vertically and horizontally with a view of bringing into gear the chain with the
adjacent wheels and also to enable the chain between the rollers to be tightened
and slackened at will.
It will be obvious that in this arrangement only one tooth of each wheel will
gear with the chain at one time, this being at the point where the roller on which
the chain rests and the wheel are nearest to each other, and that all the strain
will come direct from the driving wheel to the driven one in a straight line and
that none of the links of the chain around the rollers will have any strain whatever
upon them when rotating around the drums or rollers. It will also be obvious
that instead of half the number of teeth being geared with the chain on each wheel,
as is now usual, one only is in gear with this mechanism. And when a number
of wheels are to be driven in the same line the chain is simply extended to a
suitable length, with its supporting rollers over each wheel to be driven, the chain
only wrapping around the end rollers, so that any number of wheels can be driven
with one chain, each one having a direct pull and only one tooth gearing at one
time.
It will also be plain that on the raising of any of the rollers by means of the
vertical adjustment beforementioned, any wheel can be taken out of gear without
unfastening the chain. By this method of driving it is also obvious that any size
wheels can be used without correspondingly increasing the length of the chain, as
the rollers may remain the same size in every case and only come to the centre of
the wheels which always remains the same whatever the gear may be.

page_text: A suitable case is made to protect the chain and attached to the bearing of the
rollers already described or in any suitable manner. This case may have its back
solid with holes for the said bearings and with a ledge or moulding all around
excepting where the uppermost teeth of the wheels come into contact with the
chain. The front of the case is made with a groove or flange so as to slide into
the moulding and cover-in the whole of the chain and rollers. Or the groove or
flange may be put on the moulding, and the front be flat to slide into it, this
movable slide being arranged to get at the chain speedily when required. A drum
may also be put around each wheel and united to this chain case where it is
necessary to have the whole driving gear dust proof.
Dated this 17th day of June 1896.
A. F. SPOONER,
124 Chancery Lane, W.C., Agent for the Applicant.
Improvements in and relating to Chain Gear for Velocipedes and
other purposes.
I, TIMOTHY SHEPHERD of Kenilworth, Oakfield Road, Birmingham, in the
County of Warwick, 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:-
My invention relates to chain gear for velocipedes and other purposes, and is
designed to minimise the friction between the gear wheels and the chain through
which power is transmitted; to obtain a direct strain from one wheel to another
from the most suitable point, without having the driving strain upon a number of
the links of the chain that are in motion out of the straight line, as they usually
do when wrapped around the gear wheel; to provide means whereby a number of
gear wheels may be driven simultaneously with one chain; to enable any of the
said wheels to be taken out of gear without unfastening the links of the chain; to
enable driving and driven gear wheels of varying sizes to be employed without
variation of length of chain required; to arrange the chain in such a manner that
it can readily and cheaply be covered with a case to protect it from grit and dust,
and generally to effect the improvements hereinafter indicated.
In the accompanying drawing,
Figure 1 is a side elevation showing an application of my said invention to a
safety bicycle.
Figure 2 is a similar view to Figure 1 partly in section and drawn to an enlarged
scale showing an application thereof to the driving gear of a tandem bicycle.
Like letters indicate corresponding parts throughout the drawing.
A is the frame of the cycle, B is the driving sprocket or chain wheel, C the
driven sprocket or chain wheel, and D is the driving or pitch chain, which latter
may be of the roller, twin roller, block or any other suitable type.
In carrying my said invention into practice I make the chain D to pass around
drums or rollers E instead of around the driving and driven wheels as is usually
the case. The drums or rollers E are placed immediately above or otherwise in
close proximity to the driving sprocket or chain wheel B, and the driven sprocket
or chain wheel C, in such a manner that the chain D will gear with the teeth of
the latter. The drums or rollers E may be plain on their peripheries, or they may
have teeth, and are preferably provided with flanges as shewn in the drawing, and
are mounted on ball, roller, or other suitable bearings on suitable supports F brazed

page_text: or otherwise secured to the frame, near to the driving and driven wheels, in such
a way that the distance between the roller and the said wheels may be regulated
and adjusted both vertically and horizontally by means of slots as shown, or
otherwise, with a view of bringing into gear the chain with the adjacent wheels
and also to enable the chain between the rollers to be tightened and slackened
at will.
One or more teeth of each chain or sprocket wheel may be arranged to gear
with the pitch or driving chain D at one time. When one tooth only is in gear
this will be at the point where the roller on which the chaiu rests, and the chain or
sprocket wheel are nearest to each other, so that all the strain will come direct
from the driving wheel to the driven one in a straight line and that none of the
links of the chain around the rollers will have any strain whatever upon them when
the machine is driven in a forward direction.
When a number of wheels are to be driven in the same line, as in the case of
tandems, triplets, quadruplets, sextets and the like, the chain D is simply extended
to a suitable length, as shown in Figure 2, and an extra supporting roller E may
be placed over or otherwise in proximity to each additional driving wheel, or when
more than one wheel is driven by the same chain over or in proximity to each
additional wheel so driven, the chain only wrapping around the end rollers E, RO
that any number of driving wheels can be used or wheels driven with one chain,
each one having a direct pull.
Further advantages possessed by my improved chain gear is that on the raising
of any of the rollers by means of the vertical adjustment before mentioned and
illustrated in Figure 1 the driving wheel can be taken out and be replaced by
another of different gear, without unfastening the chain. In case of panetare,
moreover, the back wheel can be removed without touching the chain, or rollers
and thereby destroying the adjustment. It will thus be seen that any size wheels
can be used without correspondingly increasing the length of the chain, as the
rollers may remain the same size in every case and only come to or near the centre
of the wheels which always remains the same whatever the gear may be.
G is a case enclosing the rear portion of the chain D, and attached to the bearing
of the rear roller E or other convenient part, in any suitable manner. In some
instances I may extend the case throughout the entire length of the chain, and
I find it convenient to so construct the said case that its back will be solid, with
holes for the bearings, and with a ledge or moulding all around excepting where
the uppermost teeth of the wheels come into contact with the chain. The front of
the case may be made with a groove or flange so as to slide into the moulding and
cover-in the whole of the chain and rollers. Or the groove or flange may be put
on the moulding, and the front be flat to slide into it, this movable slide being
arranged to get at the chain speedily when required. A drum may also be put
around each wheel and united to this chain case where it is necessary to have the
whole driving gear dust proof.
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 !
claim is :-
1. In a chain gear, the provision of separate or independent wheels or rollers to
support or carry the driving chain, so that driving and driven, chain, sprocket, or
toothed wheels may be arranged to gear or engage therewith, substantially as set
forth.
2. The improved method of driving multicycles by means of one chain, which
may be supported by separate rollers at suitable points and attached to the
framework, and into which chain the teeth of two or a series of wheels engage on
the underside.
3. The improved gear case constructed substantially as described with reference
to Figure 2 of the accompanying drawing.
4. The improved means for permitting of the horizontal and vertical adjustment

page_text: -of-the-chain-supporting rollers-being effected, substantially as and for the purpose
-specified.
5. The improved chain gear constructed substantially as described with reference
to the accompanying drawing.
Dated this 15th day of April 1897.
A. F. SPOONER,
323, High Holborn, London, Agent for the Applicant.