Improvements in Chain Wheels and Chains.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Chain Wheels and Chains.
I, WILLIAM PATON FRASER, of 1 South Drum Place, Leith, in the County of
Midlothian, Shopkeeper, do hereby declare the nature of this invention to be as
follows:-
This invention relates to chain wheels and chains such as are used to connect
together two spindles or shafts, and is especially adapted for use with cycles. It
consists of improved forms and arrangements of the wheel teeth and chains whereby
great smoothness of running is secured, and the friction between the chain and
wheels is reduced to a minimum.
The improved wheel has instead of a single row of teeth, two or more rows formed
round the whole of its periphery, these being so arranged that some of the teeth
coincide with the intervals between other teeth. Many modifications are obviously
possible; but typical forms are as follows.
Three rows of teeth arranged so that three teeth, one in each row coincide,
followed by two coinciding with one space, next a single tooth coinciding with two
spaces, and so on. Three rows consisting of two teeth having a coinciding space
between them followed by two teeth having a coinciding space on one side, or three
rows consisting of two teeth having a coinciding space between them followed by
three, or a "three in one tooth without any coinciding space on either side.
"
The improved chains are adapted to the particular class of wheel to which they
are applied, and are either joined by screws or nuts in the ordinary manner, or by
means of hooks and pins formed integrally with or rigidly attached to alternate
links.
In some cases the connection between two links is formed by triangular or other
shaped pins, which engage with hooks; thus securing a minimum of friction.
Dated this 4th day of January 1897.
WILLIAM J. MUNDEN,
75 Chancery Lane, W.C. Agent for the Applicant.
I, WILLIAM PATON FRASER of No 1 South Drum Place, Leith, Scotland. Shopkeeper,
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 chain wheels and chains such as are used to connect
together two spindles or shafts, and is especially adapted for use with cycles. It

page_text: consists of improved forms and arrangements of the wheel and chains whereby great
smoothness of running is secured and the friction between the chain and wheels is
reduced to a minimum.
The improved wheel has instead of a single row of teeth, two or more rows formed
round the whole of its periphery, these being so arranged that some of the teeth
coincide with the intervals between other teeth. Many modifications are obviously
possible, but typical forms are as follows:-Three rows of teeth arranged so that three
teeth, one in each row coincide, followed by two coinciding with one space, next a
single tooth coinciding with two spaces, and so on. Three rows consisting of two
teeth having a coinciding space beetween them, followed by two teeth having a
coinciding space on one side, or three rows consisting of two teeth having a coinciding
space between them, followed by three, or three in one teeth without any coinciding
space on either side.
In order that my invention may be clearly understood. I append drawings in
which-
Fig. 1 is one form of chain and chain wheel suitable for driving cycles. The larger
chain wheel would be fixed on the bottom bracket spindle, and the smaller on the
rear wheel hub.
Fig. 2 is a plan view of a number of the links shewn in Fig. 1.
Fig. 3 is an edge view of one of the chain wheels shewn in Fig. 1.
Fig. 3 is an elevation and plan of two links of a modified form.
Fig. 4, 5, and 6 shew modified forms of wheel teeth.
Figs. 4 5 and 6 shew three different forms of chains which I employ when
using wheels of the description shewn in Figs. 4. 5. and 6 respectively.
In Fig 4 the chain is shewn as being composed of metallic discs, pivotally con-
nected together at their ends, and preferably being of the shape shewn. The chain is
formed by arranging a link formed of one dise, between a link formed of two discs,
alternately, the single disc being arranged with its ends between the ends of the two
discs of the next link, and pivotally connected by means of pins or screws passing
through the holes in the three discs. At the sides of and between these discs are a
fixed V shaped recesses g arranged in the following order, viz. between the discs of a
double link g so as to enable the tooth a² to engage therewith; one on each side
of the single link g² so as to cause the teeth a¹ to engage therewith; one on each
side and also between the discs of the double link g* in such manner that the three
teeth a will engage therewith; and so on.
In Fig 5ª the chain differs only from that shewn in Fig 4ª in the following
details, viz, that no double links are used, the V shaped recesses being arranged
alternately on both sides, and one side only of the discs i and respectively.
Fig. 6 shews a different form of wheel which is composed of solid discs of different
thicknesses, the link h being of a thickness equal to three times that of h¹, and being
slotted at its ends to receive the ends thereof. These teeth are arranged alternately
so that the tooth c¹, Fig. 6, shall be caused to engage with the link h, and the two
teeth c to engage the disc h¹.
3
Referring to Figs. 1. 2. and 3. A are the toothed chain or sprocket wheels which
are formed of three plates a. a¹, a³, fastened together with screws, nuts, or rivets, a³ 4
to form a solid wheel. The separate plates are so arranged, that a tooth on the two
outer plates a, a coincide with a space between them, alternating with a tooth
formed on the middle plate a¹ coinciding with a space on either side of it and so
forth. B is the chain formed of links b which are provided with V-shaped recesses b¹
to engage the teeth of the chain wheel A. The chain consists of single and double 5
links. The single links consist of a plate with recesses 61 on either side, and the
double links are formed of two plates with recesses b¹ between them.
Referring to Fig. 3A a modified double link is herein shewn. To form the
V-shaped recess a piece e is inserted and fastened between the two side plates forming
the link. The single link is the same as that previously described.
In Fig. 4 the teeth are arranged as follows; one row consisting of three teeth a,
followed by two teeth a¹ having a coinciding space between them, next a single
5

page_text: tooth a² having a space on both sides, and so on. In Fig. 5 the teeth are arranged so
that one row, consisting of two teeth b, having a coinciding space between them, is
followed by two teeth 6¹ having a space on one side. In Fig. 6 the teeth are arranged
so that one row consisting of two teeth c having a coinciding space between them, is
followed by three, or three in one teeth c¹. This wheel may if preferred be formed of
one plate only as shewn.
66
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. An improved chain and sprocket driving gear consisting of a chain wheel made
up of two or more plates formed integral with each other, or fastened together, the
teeth of which are so arranged that some of the teeth_coincide with the spaces-
between-other-teeth-;-and a chain, made up of single and double links, provided with
recesses to engage the teeth of the chain or sprocket wheel, substantially as described
and shewn with reference to Figs. 1. 2 and 3.
2. For use in the improved chain and sprocket driving gear, the double and single
links provided with recesses to engage the teeth of the chain wheel, substantially as
described and shewn with reference to Figs. 1. 2. 3 and 3^.
3. For use in an improved chain and sprocket driving gear, the chain wheel A made
up of two or more toothed plates formed integral with each other, or fastened
together by rivets, screws or nuts a³, the teeth in which plates are so arranged that
the teeth in one of the plates coincide with a space or spaces between teeth formed
on the other plate or plates, substantially as described and shewn.
4. The improved chain and sprocket driving gear, substantially as shewn and
described with reference to Figs. 1. 2. and 3.
5. The improved chain and sprocket wheel having teeth formed substantially as
shewn and described with reference to Figs. 4, 5, and 6.
Dated this 24th day of Amanet 1907
WILLIAM J. MUNDEN,
75 Chancery Lane London W.C. Agent for the Applicant.