Improvements relating to Driving and Brake Mechanisms for Velocipedes and the like.
Year: 1899

page_text: Date of Application, 17th June, 1899
Complete Specification Left, 19th Mar., 1900-Accepted, 5th May, 1900
PROVISIONAL SPECIFICATION.
"
Improvements relating to Driving and Brake Mechanisms for
Velocipedes and the like.
We, JOHN HAYTHORN, of Mansewood, Pollokshaws, in the County of Renfrew,
Engineer and JAMES RICHARD NISBET, of 19, Queen Street, Glasgow, Printer
and Publisher, do hereby declare the nature of this invention to be as follows:-
Our invention relates to mechanism for the transmission of power from one
shaft or pulley to another shaft or pulley and in which the driven shaft or pulley
is free to over-run the driver, the arrangement being such as to be capable of
being driven in the reverse direction the act of reversal checking the momentum
of the driven shaft or pulley and in some cases applying a positive brake.
Our invention is particularly adapted to the driving of velocipedes and by its
aid a rider is enabled (a) to propel his machine in the ordinary way of forward
pedalling (b) to cease pedalling and maintain his feet on the pedals without
hindrance to the progress of the machine (c) to preserve control of his machine
by back-pedalling and (d) in some cases to apply a positive brake by the act of
back-pedalling, and also to positively lock the parts of the gear together.
Our invention embodies a clutch of novel construction and comprises the other
improvements hereinafter indicated.
According to our invention the clutch is preferably applied to the driven wheel.
The said wheel is mounted free upon its spindle and it has a recessed hub into
which is loosely fitted a split ring. A cam is located at the split and is adapted
to expand the said ring against the internal walls of the recessed hub when the
cam is turned to either side of its normal central position. The cam has a tail
which preferably extends toward the spindle and enters a notch in the hub of a
sprocket wheel, which is also free to revolve on the said spindle or extended end
of the hub on which it is held by a nut or other suitable means. Forward
motion is imparted to the sprocket wheel by a chain or its equivalent which at
first moves the said sprocket wheel alone until the notch in its hub has canted
the cam sufficiently to expand the split ring against the internal walls of the
recessed hub, whereafter all the parts move together and as a result the machine
is driven. When the rider ceases to exert pressure upon the pedals the cam
returns to its central position under the influence of a spring, or of the split
ring which contracts by virtue of its own elasticity, and the hitherto driven
wheel is free to rotate by itself. In like manner when back pressure is exerted
on the pedals (back-pedalling) the cam is canted in the opposite direction ex-
panding the split ring and bringing it into frictional contact with the wheel
hub.
In adapting our improved mechanism to apply a positive brake by back-
pedalling, we use a split ring provided with two half bosses, each half being
supported by an arm extending inwardly from the sides of the ring and at
right angles to the splits. To the side of the split ring nearest the bottom of the
recessed hub we apply a brake surface consisting of a metal disc covered with
leather or other suitable material, while the split bosses are provided with

page_text: notches having inclined or helical outer edges adapted to co-operate with pro-
jections formed on the adjacent end of the sprocket wheel boss. Or the relative
positions of the parts may be reversed, and in this case when the sprocket wheel
is driven forward the projections on its boss enter the deepest end of the notch
allowing a spring to keep the brake surface clear of the bottom of the recessed
hub but on the motion being reversed the said projections rise up the inclines and
apply the brake.
In a modification the split ring is expanded by means of two inwardly pro-
jecting levers which are fulcrummed in the split ring one on each side of the
split. These levers are linked together at their outer ends while stops prevent
their inner ends from approaching each other. A tooth on the sprocket wheel
extends between the inner ends of these levers which are forced apart and their
fulcra separated thereby expanding the split ring when the sprocket wheel is
rotated in either direction.
According to a further modification the tail of the split ring expanding cam
is provided with a pin extending towards the bottom of the recess in the hub,
where it may be engaged by a slotted part adapted to lock the said cam to the
wheel hub and establish a positive connection between the driven wheel and the
sprocket wheel through the tail of the cam and the pin. This slotted part is
pivoted to the driven wheel hub at a point opposite the path of the said pin and
is adapted to be turned by a key through a suitable angle for which purpose it
is provided with limiting stops and a pointer.
In one of these positions the slotted portion inside the recessed hub has a
circumferential direction which freely allows the said pin to pass through it
without interference, but when it is desired to lock the parts together the said
pin is first moved, by the rotation of the sprocket wheel, into the said slotted
part which is then turned by means of the key to its other position thereby con-
fining the said pin between the walls of the slot which now have a radial
direction.
We may further modify the construction by providing other equivalent means
of operating the split-ring expanding cam or levers, such as by a pin fixed to
the sprocket wheel which enters a slot in the tail of the said cam or levers.
The above disconnecting and brake appliances may be adapted to bevel and
similar gear.
Improvements relating to Driving and Brake Mechanisms for
Velocipedes and the like.
We, JOHN HAYTHORN, of Mansewood, Pollokshaws, in the County of Renfrew,
Engineer and JAMES RICHARD NISBET, of 19, Queen Street, Glasgow, Printer
and Publisher, 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:-
Our invention relates to mechanism. for the transmission of power from one
shaft or pulley to another shaft or pulley and in which the driven shaft or pulley
is free to over-run the driver, the arrangement being such as to be capable of
being driven in the reverse direction the act of reversal checking the momentum
of the driven shaft or pulley and in some cases applying a positive brake.

page_text: Our invention is particularly adapted to the driving of velocipedes and by its
aid a rider enabled (a) to propel his machine in the ordinary way of forward
pedalling (b) to cease pedalling and maintain his feet on the pedals without
hindrance to the progress of the machine (c) to preserve control of his machine
by back-pedalling and (d) in some cases to apply a positive brake by the act of.
back-pedalling, and also to positively lock the parts of the gear together.
Our invention embodies a clutch of novel construction and comprises the other
improvements hereinafter indicated.
In the accompanying drawings, which are illustrative of our invention.
Figure 1 is a vertical section through the hub of the rear or driven wheel of
a bicycle.
Figure 2 is a side elevation thereof looking towards the left, the chain wheel
and clutch box cover being removed, and
Figure 3 is a side elevation of the removed parts, viewed from the opposite
direction.
Figure 4 is a similar view to Figure 1 but with the sprocket wheel h carried
on balls, and
Figure 5 is a view corresponding with Figure 3, illustrating a modification and
embodying a back-pedalling brake.
Figure 6 is a half sectional elevation, and
Figure 7 is a side elevation looking in the direction of the arrow in Figure 6,
of a further modification provided with means of converting the free-wheel clutch
into a positive driving gear.
Figures 8, 9, 10 and 11 illustrate a modification,
Figure 8 being a half-sectional side elevation, and
Figure 9 a plan, of the clutch ring, and
Figure 10 a side elevation, and
Figure 11 a partial plan of the co-operating portion of the chain wheel boss
and clutch box cover.
According to our invention the clutch is preferably applied to the driven wheel.
The said wheel, of which the hub a alone is shown, is mounted free upon its
spindle b the said hub a being recessed and provided with a loosely fitting split-
ring c.
A cam or pawl d is located at the split and is adapted to expand the said
ring c against the internal walls of the recessed hub a when the cam is turned
to either side of its normal central position. The cam has a tail e which pre-
ferably extends toward the spindle and enters a notch f in the hub g of a sprocket
wheel h which is also free to revolve on the said spindle or extended end of the
hub on which it is held by a nut i or other suitable means. Forward motion
is imparted to the sprocket wheel by a chain or its equivalent which at first moves
the said sprocket wheel h alone until the notch f in its hub has canted the cam d
sufficiently to expand the split-ring c against the internal walls of the recessed.
hub, whereafter all the parts move together and as a result the machine is driven.
When the rider ceases to exert pressure upon the pedals the cam returns to its
central position either under the influence of a spring not shown or of the
split-ring itself which contracts by virtue of its own elasticity, and the hitherto
driven wheel is free to rotate by itself. In like manner when back pressure is
exerted on the pedals (back-pedalling) the cam is canted in the opposite direction
expanding the split-ring c and bringing it into frictional contact with the wheel
hub.
C
In adapting our improved mechanism to apply a positive brake by back-
pedalling, (see Figures 4 and 5) we use a split-ring c substantially similar in form
to that shown in Figure 2. provided with two half bosses j, each half being
supported by an arm k extending inwardly from the sides of the ring and at
right angles to the splits. To the side of the split-ring nearest the bottom of
the recessed hub we apply a brake surface consisting of a metal disc / covered
with leather m or other suitable material, while the split bosses are provided with
projections adapted to co-operate with notches o having inclined or helical

page_text: outer edges formed on the adjacent face of the sprocket wheel boss. Or, the
relative positions of the parts may be reversed, and in this case when the sprocket
wheel is driven forward the projections n on the split boss j enter the deepest
ends of the notches o allowing a spring p to keep the brake surface clear of the
bottom of the recessed hub but on the motion being reversed the said projec-
tions rise up the inclined edges of the notches o causing the split boss and
11s supported, rim to be moved laterally towards the bottom of the recess,,so
as to force the brake pad m into contact with it.
In a modification, as illustrated by Figures 8, 9, 10 and. 11, the split-ring c
is expanded by means of two,inwardly projecting levers 7 which are fulcrummed
in the split-ring one on each side of the split.
These leyers occupy recesses t located near the split in the ring.c and are
rivetted or otherwise suitably secured between two discs r. These discs, con-
stitute the fulcra of the levers.q, and the said levers are journalled in bearings s
formed on both sides of the said recesses f. These levers q are connected together
at their outer ends by links while stops prevent their inner ends from
approaching each other. A tooth (see Figures 10 and 11) on the boss g of
the sprocket wheel h extends between the inner ends of these levers q which are
forced apart and their fulcra separated, so as to expand the split-ring, when the
sprocket wheel is rotated in either direction.
According to a further modification, as shown in Figures 6 and 7, the tail e
of the cam is provided with a pin extending towards the bottom of the
recess in the hub where it may be engaged by a slotted part y adapted to lock
the said cam to the wheel hub and establish a positive connection between the
driven wheel and the sprocket wheel through the tail e of the cam and the
pin z. This slotted party is journalled in the hub at a point
opposite the path of the said pin and is adapted to be turned by a key through
a suitable angle for which purpose it is provided with limiting stops 1 and a
pointer 2.
In one of these positions the slotted portion inside the recessed hub has a
circumferential direction as shown by dotted lines in Figure 7 which.. freely
allows the said pin to pass through it without interference, but when it is desired
to lock the parts together the said pin is first moved, by the rotation of the
sprocket wheel ; into the said slotted party which is then turned by means of
the key to its other position thereby confining the said pin between the walls
of the slot which now have a radial direction.
We may further modify the construction by providing other equivalent means
not shown for operating the split-ring expanding cam or levers, such as by a pin
fixed to the sprocket wheel which enters a slot in the tail of the said cam or levers.
The above disconnecting and brake appliances may be adapted to bevel and
similar gear.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:
1. The combination, in a. clutch-gear, of a recessed hub, a freely-mounted
sprocket wheel adjacent thereto and a split-ring provided with a can of pawl,
Eo arranged that the partial rotation of the sprocket wheel in either direction
cants the cam or pawl and expands the split-ring substantially as set forth.
2. The combination, in a clutch-gear of a recessed hub, a freely-mounted
sprocket wheel adjacent thereto, a split-ring provided with a cam or pawl
a brake-surface on one of the said parts and one or more inclines on the other of
the said parts, so arranged that the partial forward rotation of the sprocket wheel
cants the cam or pawl and expands the split-ring," whilst the partial backward
rotation of the said sprocket wheel in addition actuates the said brake substantially
as set forth.
3. In a clutch-gear, the device for establishing a positive connection between

page_text: the driven wheel and the sprocket wheel substantially as described with reference
to Figures 6 and 7 of the accompanying drawings.
4. In a clutch-gear, the split-ring expanding device substantially as described
with reference to Figures 8, 9, 10 and 11 of the accompanying drawings.
5. The clutch-gear constructed substantially as described with reference to
the accompanying drawings.
Dated this 17th day of March 1900
A. F. SPOONER,
323, High Holborn, London, Agent for the Applicants.