Improvements in Bicycles and Tricycles.
Year: 1890

page_text: Date of Application, 8th Dec., 1890
Complete Specification Left, 8th Sept., 1891-Accepted, 24th Oct., 1891
PROVISIONAL SPECIFICATION.
Improvements in Bicycles and Tricycles.
We ALBERT POHLMANN of Parkinson Lane, Halifax, in the County of
York, Mechanical Engineer, and LOUIS POHLMANN FOSTER, of Bank Chambers
Halifax, aforesaid, Solicitor, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in the driving mechanism of bicycles
and tricycles, whereby the use of cranks and the rotary motion of the pedals are:
dispensed with consequent reduction in weight is available.
Its
According to this our said invention we employ on the axis of the front or
back wheels a pulley and a stretcher wheel at a distance therefrom over which
the driving chain or strap runs. Attached to the side of the driving chain or
strap by a lug is a socket through which the upright arm of a bent lever passes.
The said lever is of form somewhat similar to the letter L (inverted 7).
lower extremity forms a centre on which it is free to rock whilst the other and
upper extremity carries the ordinary pedal and as the levers are worked to and
fro the socket slides along the lower limb of the lever thereof admitting the
required motion when passing from the lower to the higher position and over the
chain wheels.
The position of the 7 lever and its to and fro movement enables the operator
to apply pressure at advantage and also to obtain an increased movement or stroke
whereby the effective force is utilized.
In some cases in lien of the sliding sockets the connection between the levers
and the chain or strap may consist of a swivel link or bar which will admit of
the required play in passing over the pulleys.
Dated the 6th day of December 1890.
WALTER
BRIERLEY,
Central Chambers, Halifax, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Bicycles and Tricycles.
We ALBERT POHLMANN, of Parkinson Lane, Halifax, in the County of
York, Mechanical Engineer, and LOUIS POHLMANN FOSTER, of Bank Chambers
Halifax, aforesaid, Solicitor, 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 improvements in the driving mechanism of bicycles,
tricycles and velocipedes whereby the use of cranks, and the rotary motion of the
pedals is dispensed with, and a consequent reduction in the size, and weight of the
machine is obtained.
According to this our said invention we employ on the axis of the front, or back
driving wheel, or wheels a pulley, or chain wheel and a stretcher, or guide wheel,
or pulley at a short distance therefrom over which the driving chain, or strap runs.
Attached to each side of the driving chain, or strap by a lug or pin is a socket
through which the upright arm of a bent lever passes. The said lever is of form
somewhat similar to the letter L (inverted 7). Its lower extremity forms a centre
on which it is free to rock whilst the other, and upper extremity carries the
ordinary pedál, and as the levers are worked to, and fro the socket slides along one

page_text: mong the required motion from the pedals
to the driving wheel, and so propelling the machine.
The position of the lever, and its to and fro, or up and down movement enables
the operator to apply pressure at advantage, and also to obtain an increased
movement, or stroke whereby the effective force is utilized..
Such being the nature, and object of our said invention, the following is a
complete description of same reference.being had to the accompanying drawings in
which:-.
Fig. 1 is a view in elevation of a bicycle having our improved driving mechanism
applied thereto.
'4
or
Fig. 2 is a side elevation of bent or lever, socket, and part of driving chain,
strap drawn detached from the machine in order to more clearly shew its con-
struction.
Fig. 3. is a back view in elevation of our improved driving mechanism shewn
applied to one side only of the driving wheel of a bicycle.
Fig. 4 is a detail of upper end of bent or ☐ lever, socket, and part of driving
chain.or. strap.
Fig..5 is a plan view of Fig. 4.
According, to this our said invention on the axis of the front, or back driving
wheel 2. of a bicycle, tricycle, or other velocipede we mount a chain wheel, or
pulley 3.and at. a short distance from said wheel, or pulley 3 we mount a stretcher,
or guide wheel; or pulley 4 and by these two pulleys, or wheels 3. 4 a driving chain
or strap.5 is carried: Attached to each side of the driving chain, or strap 5 by
lug, or pin.6 is a socket 7. 8 through which the arm 9 of a bent or lever 10
passes; the arm 9.passing through the socket 7 on one side of the chain or strap 5,
and is then bent, or curved (see Fig. 3) and carried through the socket 8 on the
opposite side of the chain, or strap 5, an open space 94 being left in the arm 9 so as
to pass the axis 1.
The bent, or lever 10 is carried on a centre, or fulcrum 11
on which it is free to rock or oscillate, and such fulcrum, or centre is at. the
elbow, or angle of the lever 10 one arm 9 extending to the chain, or strap as,
above described, and the other arm 12 carries the ordinary pedal 13. 131. The
centre or fulcrum 11 of the lever 10 is fixed to the frame 14 of the machine, and
the stretcher or guide wheel, or pulley 4 is also mounted on the frame,14.
One bent or lever 10, and one complete, driving apparatus as above described,
is placed on each side of the driving wheel 2 though the machine can be driven
from one side only. The sockets 7. 8 are formed of a small plate of metal 15 on
which are mounted two, or four anti-friction bowls or runners 16, 16 between which
the arm 9 of the lever 10 passes; or ordinary ball, or roller bearings may be
employed with the sockets 7.-8-in order to reduce the friction between the said
arm 9 and the sockets to a minimum, the sockets being free, to move or rock on the
pin 6 by, which they are attached to the chain, or strap 5.
The
11.
4"
"
action IS as, follows When, pressure is applied by the rider to one of the
pedals: 13 the lever 10 is rocked, or moved on its centre, or fulcrum 11 and the
upper end, of the arm, or limb 9 will move forward, or towards the machine, (see,
Fig. 1) and carry with it the socket 7 and chain or. strap 5, at the same time the...
pedal, lever, and socket 8 on the opposite side of the machine, are moving in a
reverse direction.
T
As soon as the socket 7 has been moved to about the dead centre, or point A of the
stretcher wheel 4 the pedal 13' on the other side of the machine will be coming into
the effective part of its stroke and the motion is thus continued, the socket 7 passing
part around the guide or stretcher wheel 4 thence to, and part, around the chain
wheel 3' whereon the pedal 13 (having risen whilst the socket 7 was moving to the
chain wheel 3) is again depressed by the rider, the power expended by the rider
being more effective, than with an ordinary cycle motion owing to there, being
practically very little "dead centre" or points in the movement where neither
pedal is effectively operative."
During the movement of the chain, or strap 5 around the two wheels, 3. 4 the.

page_text: sockets 7. 8 will move up, and down the arm 9, and the runners 16, and pin 6
reduce friction, and prevent binding at any point.
The position of the lever 10 and its peculiar movement, the up, and down, and
slightly forward motion of the pedals 13 and the relative positions of the saddle 17
and rider, and driving mechanisin enables the operator to apply pressure, or power
at advantage, and also to obtain increased movement, or stroke whereby his
effective force is utilized, at the same time the machine looses none of its strength,
or rigidity, the driving mechanism being all carried on the driving wheel the
wheels of the cycle can be brought much nearer together, and consequently the
frame 14 and machine are lighter, and more compact, and the weight of the rider is
carried almost entirely on the driving wheel, and steering is facilitated.
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. The improvements in bicycles, and tricycles wherein is employed in com-
bination a socket attached to the driving chain the socket and chain being operated
by the arm of a lever as described and illustrated by drawings annexed.
2. The employment of a socket attached to the driving chain, a guide and
stretching pulley and operating lever all in combination as and for purpose herein
described.
Dated this 5th day of Santamban 1901
ALBERT POHLMANN.
LOUIS POHLMANN FOSTER.
By their Agent, Walter Brierley,
Bank Chambers, Waterhouse Street, Halifax.