Improved Friction Chain and Disc Driving Gear for Velocipedes and General Light Machinery,
Year: 1898

page_text: Date of Application, 13th July, 1898
Complete Specification Left, 12th May, 1899-Accepted, 1st July, 1899
PROVISIONAL DIECIFICATION.
Improved Friction Chain and Disc Driving Gear for Velocipedes and
General Light Machinery,
We, EDWARD AUGUSTUS JEFFREYS, Mechanic, residing at "Highfields," Laurel
Road, Handsworth, in the County of Stafford, and ALFRED APPLEBY, of 124, Vyse
Street, in the City of Birmingham, Manufacturer, do hereby declare the nature
of this invention to be as follows:-
This invention is an improved friction chain and disc driving gear for cycles,
motor cars, and other light machines and vehicles. The said driving gear is in
one form, vi;-chain driving gear-characterised by a wheel or wheels, over
which the chain runs, having its or their peripheries formed with a circumferen-
tial coned groove or trough having inclined sides, and a chain whose points of
contact with the said groove or trough are of a partly spherical or other shapo
so that it shall tighten or wedge itself circumferentially in the said groove or
trough of the wheel, as aforesaid, but shall be free to leave the said groove radially
without jamming. The sides of the groove or trough are accurately machined
to form equal angles, making the bottom of the said groove or trough the smallest
in breadth. The points of contact upon the chain are preferably the partly
spherical heads of the cross rivets which connect the links forming the drive
chain together.
The said drive chain is preferably built up of opposite pairs and single links
of a flat plate construction, but the partly spherical points of contact thereof
may be formed from the sides of the pairs of links instead of from the heads of
the cross rivets.
The mouth of the groove or trough in the chain wheel is large enough to form
a lead thereto for the chain, and the chain fits into the said groove or trough
below the wheel's extreme face, and so that it grips the said wheel by coming in
contact with the groove's inclined walls or sides.
As a modification of this one form of the invention, instead of the points of
contact of the chain being rounded they may be flat but inclined to correspond
with and fit the sides of the trough.
According to another form of this invention, viz:-disc driving gear-which
is suitable for all light gearing where toothed gearing is now used, a wheel
having a coned groove, or a trough with inclined sides, sunken within its
periphery is constructed, and another wheel having its circumference formed
with partly spherical contacts, or the equivalent of those of the previous described
chain is fashioned to gear into this grooved wheel. The gear wheel with the
groove or trough within it is built up of sectional parts, that is to say, its sides
are two discs or plates which are spaced so as to form, when set up, an inclined
groove, and which are so carried that the width of the said groove can be adjusted
by bringing the said plates closer to, or at a greater distance from, each other.
This adjustment compensates for any wear in the contact surfaces of the fric-
tionally geared together wheels, and it allows of a very fine adjustment and a
locking thereof.
The wheel or disc with the partly spherical points of contact has its circum-

page_text: ference so nicely formed or shaped that although a radial friction is created when
driving there shall be no sticking or jamming of the contact parts as they come
to the point of leaving each other.
This friction disc driving gear can be set up as a high or low speed gear
exactly in the same way as is the majority of toothed gearing at present, and it
is very applicable for cycle driving.
Improved Friction Chain and Disc Driving Gear for Velocipedes and
General Light Machinery.
دو
We, EDWARD AUGUSTUS JEFFREYS, Mechanic, lately residing at "Highfields,"
Laurel Road, Handsworth, in the County of Stafford, but now of Thistlewood,"
Coppice Road, Moseley, in the City of Birmingham, and ALFRED APPLEBY, of
124, Vyse Street, in the City of Birmingham, Manufacturer, 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 is an improved friction chain driving gear for light vehicles
and machines, and comprises a drive chain of a particular construction as herein-
after described, and discs or pullies having their peripheries or circumferences
set up with annular grooves or troughs formed with inclined sides or taper, the
said chain being adapted to fit within the said grooves or troughs so that parts
of it frictionally engage their inclined sides and grip onto the wheel by wedging
themselves therein, the depth of the said grooves or troughs being sufficient to
allow of this wedging action.
To make the invention, clear and illustrate its practicability a sheet of draw-
ings is annexed showing the various forms of carrying the same into effect.
The chain according to Fig. 1 is built up of inner links a and outer links c,
cross rivets d jointedly connecting them, but the heads of these rivets are counter-
sunk below the sides c2 of the links c. One of these outer links is shown in per-
spective and bracketed to Fig. 1, from which it will be seen that the sides are
tapered or inclined at equal angles, making the bottom of the link the smallest.
Such a link could be formed from a metal blank by suitable dies. The links a, c,
are connected by the cross rivets in the centre of the links c.
A wheel or disc suitable for a chain according to this invention to work upon
is shown in Fig. 2, it having a coned groove or trough e, having inclined
sides e, of a depth greater than that of the chain, formed within its periphery.
The mouth e of the groove or trough is the largest part and forms a lead for the
chain, which fits the said groove or trough wedge-like by coming in contact with
the inclined sides, the sides of the links c and the groove or trough e being accu-
rately machined to similar angles for the purpose.
In Fig. 3 is a top view of a form of chain in which the points of contact with
the groove or trough e are partly spherical and formed from the ends d of the
cross rivets d which connect together jointedly the inner and outer links a, c.
In the chain according to this invention as shown respectively in side elevation,
underside plan, and end section in Figs. 4, 5 and 6, the points of frictional con-
tact with the sides of the groove or trough e of the wheel or disc are shown as
inclined ribs or facets, a², &, projecting respectively from the inner links a and
the outer links c which are coupled by cross rivets & in a similar manner as the

page_text: links of the chain in Figs. 1 and 3. Fig. 6 shows how the chain engages the
groove of the wheel. Fig. 7 shows a top, side and end view of one of the outer
links c in Figs. 4 to 6, whilst Fig. 8 shows like views of one of the inner links a,
the gripping surfaces of the ribs or facets a, e, in Figs. 4 to 8 being flat, but
they may be curved as illustrated in the end section Fig. 9, although a flat
formation is preferred.
It will be obvious that in gripping around a pulley the points of contact of
the chain must be as it were free or independent of each other in finding their
proper seating within the groove, and that their opposite gripping surfaces be
nicely machined to the angles of the sides of the groove.
The points of frictional contact need not be formed on each and every link of
the arrangement Figs. to 6; those on either links could be dispensed with, or
they could be formed on every second link, although too little gripping surface
is to be avoided in order to prevent any chance of the points of frictional contact
jamming in the groove of the wheel. It will be observed that the links in the
arrangement Figs. 4 to 6 are connected by the cross rivets at their middles, as
in the forms in Figs. 1 and 3. In Fig. 10 a diagram shows the application of
the invention in multiple or in a compound sense, that is to say, three chains
constructed according to this invention working in three grooves in the periphery
of a pulley, the said chains being either connected by a yielding band
as required.
g or not
Such a friction chain gear has considerable utility as a means for communi-
cating motion in light machines and mechanisms, especially where a non-slipping
driving band is desirable.
Contact points in the forms of chain Figs. 1, 4, 2, 8, and 9 are solid with the
links forming the drive chain which insures great strength.
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: -
First. A friction chain driving gear characterised by discs or pullies having
annular grooves or troughs formed with inclined sides or taper, and drive chain
constructed of jointed together parts or links carrying either directly or indi-
rectly on their sides points of contact which have a wedge action within the said
grooves or troughs when the chain is in position within them, substantially as
described.
Second. A chain formed of parts or links having taper or inclined ribs or
facets or similar points of contact upon their sides, and whose parts or links aro
jointedly connected in the centre or at their middles, substantially as and for
the purpose described.
Third. The combination with a disc or pulley having an angular groove or
trough formed with taper sides as set forth, of a chain with jointed links carry-
ing on their sides ribs, facets or similar contact points, substantially as set forth
in Figs. 4 to 8.
Fourth. A drive chain having its frictional contact points formed in the
manner substantially as set forth in Figs. 1 and 3 in combination with a pulley
or disc constructed in the manner set forth in Fig. 2.
Dated this fith day of May 1899.
W. P. THOMPSON & Co..
11, Burlington Chambers, New Street, Birmingham,
Also of Liverpool, London; and Manchester,
Patent Agents for the Applicants.