Improvements in Driving-gear for Velocipedes.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Driving-gear for Velocipedes.
I, CHARLES WALTER VOSPER, of 3, Nelson Terrace, Newport Road, Barnstaple,
in the County of Devon, Engineer, do hereby declare the nature of this invention
to be as follows:-
-
My invention relates to improved driving-gear for velocipedes, and is chiefly
designed to provide for the use of multiplying-gear of the kind commonly known
as the "Crypto" gear in connection with the rear wheel of a bicycle, instead
of with the front wheel thereof as heretofore, without the necessity of employing
a chain. I thus combine all the advantages of a chainless safety-bicycle with
those afforded by the aforesaid multiplying-gear.
The so-called "Crypto" gear comprises a fixed internally-toothed ring which
is usually secured to the front fork of the machine, a toothed wheel fixed upon
the wheel-hub and concentric with the said ring, and a disc formed or fixed on a
crank-shaft extending through the said hub, which disc carries toothed pinions
that are geared both with the said toothed wheel on the hub and with the
said internally-toothed fixed ring.
Now in carrying my present invention into practice, I form or fix the said
toothed wheel on the hub of the rear wheel of the machine, and firmly attach
the said internally-toothed ring to the rear fork or back stay at one side of the
machine.
Instead of arranging the cranks of the said crank-shaft at an angle of one-
hundred-and-eighty degrees to each other as heretofore, I arrange them at a right
angle to each other. And I couple each crank of the said crank-shaft by means
of a connecting-rod or link, to a crank on the pedal-shaft, which is mounted
in bearings in a bottom-bracket as is usual in safety-bicycles. I find it advan-
tageous, in order to make the "tread" as narrow as practicable, to provide at
each end of the pedal-shaft, a bent double crank, that is to say, a pedal-crank
having a supplementary crank-pin between the pedal and the shaft, these cranks
being arranged at a right angle to each other and being coupled as above
mentioned to the cranks of the aforesaid multiplying-gear, and the webs of the
pedal-cranks being bent so as to bring the pedals diametrically opposite each
other or set them at the usual angle of one-hundred-and-eighty degrees to each
other.
I can,
if desired, use other suitable means for transmitting motion from the
pedal-shaft to the aforesaid disc carrying the toothed pinions. For instance I
sometimes connect the shaft on which the said disc is formed or fixed, to the
pedal-shaft by suitable gearing, such, for example, as wheels with teeth on the
periphery thereof set at a suitable angle, geared with crown-wheels or face-

page_text: wheels having teeth set at a corresponding angle. By changing these wheels,
I can, when desired, alter the speed or gear" of the machine.
Dated this 9th day of November 1897.
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements in Driving-gear for Velocipedes.
I, CHARLES WALTER VOSPER, of 3, Nelson Terrace, Newport Road, Barnstaple,
in the County of Devon, 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 improved driving-gear for velocipedes, and is chiefly
designed to provide for the use of multiplying-gear of the kind commonly known
as the "Crypto" gear, in connection with the rear wheel of a bicycle, instead
of with the front wheel thereof as heretofore, without the necessity for employing
a chain. I thus combine all the advantages of a chainless safety-bicycle with
those afforded by the aforesaid multiplying-gear.
*
The so-called Crypto" gear comprises a fixed internally-toothed ring which
is usually secured to the front fork of the machine, a toothed wheel fixed upon
the wheel-hub in the centre of the said ring, and a disc formed or fixed on a
crank-shaft extending through the said hub, which disc carries toothed pinions
that are geared both with the central toothed wheel on the hub and with the
concentric internally-toothed fixed ring.
Now in carrying my present invention into practice I form or fix the central
toothed wheel on the hub of the rear wheel of the machine, and I firmly attach
the concentric internally-toothed ring to the rear fork or back stay at one side
of the machine. And I couple each crank of the crank-shaft, by means of a
connecting rod or link, to a crank on a pedal-shaft mounted in bearings in a
crank-bracket or bottom-bracket situated between the front and rear wheels, as
is in a safety-bicycle, so that motion may be transmitted from the said pedal-
shaft to the aforesaid disc carrying the pinions. Instead of arranging the cranks
of the said crank-shaft at an angle of one-hundred-and-eighty degrees to each
other as heretofore, I arrange them at a right angle to each other.
I sometimes provide at each end of the pedal-shaft a bent double crank, that
is to say, a pedal-crank having a supplementary crank-pin between the pedal
and the shaft, these double pedal-cranks being arranged at a right angle to
each other and being coupled as above mentioned to the cranks of the aforesaid
multiplying-gear, and the webs of the said pedal-cranks being bent in their
plane of rotation so as to bring the pedals diametrically opposite each other or
set them at the usual angle of one-hundred-and-eighty degrees to each other. I
find it more advantageous, however, in order to make the "
tread " as narrow as
practicable, to provide a double pedal-crank at one end only of the pedal-shaft
and to employ an ordinary pedal-crank at the other end coupled by a rod or link
to a crank of equal length on the crank-shaft of the multiplying-gear.
In place of the said cranks and connecting-rods, I can, if desired, use any
known form of transmission-gear for communicating motion from the pedal-
shaft to the aforesaid disc carrying the toothed pinions.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.

page_text: Figure 1 is a plan, partly in horizontal central section through the hub of
the driving-wheel, and
Figure 2a side elevation of part of a velocipede having my improved driving-
gear fitted thereto.
Figure 3 is a plan, and
Figure 4 a side elevation, illustrating a modified arrangement of my improved
driving-gear.
66
A is the frame of the machine; B is the driving-wheel; C is the pedal-crank-
shaft; D is the hub of the driving-wheel which is arranged to turn in bearings Di
in the rear forks of the frame A. On the lower rear fork, concentrically with
the hub D, is secured an internally-toothed ring or internal gear-wheel E, and
on an extension of the hub, projecting through the corresponding bearing D',
is mounted a toothed wheel F, the relative numbers of teeth on the pinion F
and on the internal gear-wheel. E determining the multiplying effect or gear'
of the driving-mechanism. Passing through the hub D and turning in
bearings 2 therein, is an axle or shaft G on which is fixed a disc or carrier G¹
bearing four gear-wheels H turning on studs fixed in the said carrier, and
geared with both of the gear-wheels E and F, so that, by turning the said axle
or shaft G about its axis, the hub I will be rotated in the same direction at
an increased velocity depending on the relative numbers of teeth in the gear-
wheels E, F as above described. By arranging the disc G¹ so that it fits closely
in a recess in the exterior of the ring or gear-wheel E, dust can be practically
excluded from the interior of the latter.
Motion is imparted from the pedal-shaft C to the axle or shaft G through
cranks J fixed on the said shaft G at an angle of 90 degrees to each other and
coupled to a pair of similar cranks K on the crank-shaft C by means of con-
necting-rods or links L.
In the arrangement shown in Figures 1 and 2, crank-webs K2 bearing at their
ends the pedal-pins M, are rigidly secured on the outer ends of the crank-pins K',
the said crank-webs K2 being set at such an angle to the crank-webs K respec-
tively that the pedals will be diametrically opposite one another.
In the arrangement shown in Figures 3 and 4, an ordinary pedal-crank K³
is fixed on one end of the pedal-shaft C and is coupled by a rod or link L to a
crank J of equal length fixed on the shaft G. In this case, the pedal-crank-
web K2 is fixed at such an angle to the crank-web K as to set the pedals
diametrically opposite one another.
By arranging the cranks J, J at an angle of 90 degrees to each other and
employing one or two bent or double cranks on the pedal-shaft, I am enabled
to obviate dead points in the revolution of the driving-gear.
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. The improved driving-gear in which multiplying-gear of the kind herein-
before referred to, is arranged in combination with the rear driving-wheel and
is connected through suitable transmission-gear to a pedal-crank-shaft supported
in bearings between the front and rear wheels, substantially as hereinbefore
described, and for the purposes specified.
2. A bicycle provided with driving-gear constructed substantially as described
with reference to the accompanying drawings and operating as above specified.
Dated the 26th day of March 1808
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.