An Improved Driving Chain.
Year: 1891

page_text: Date of Application, 6th June, 1891
Complete Specification Left, 5th Mar., 1892-Accepted, 30th Apr., 1892
PROVISIONAL SPECIFICATION.
An Improved Driving Chain.
I, LOUIS GAUTIER of Saint Malo, France, Mechanician, do hereby declare the
nature of this invention to be as follows:
:-
This invention has reference to a construction of chain designed to transmit
rotary movement between two parallel shafts provided with gear wheels the teeth
of which enter the links of the chain.
My improved chain is of the type known as the "Galle" chain, but it differs
from such a chain in several important features.
In a
"Galle" chain the links are jointed by cylindrical pins accurately fitting
holes formed in the short connecting pieces constituting the links of the chain.
With this construction friction is produced over the whole surface of the pin by
rotary or rocking movements having an angular amplitude generally smaller
than 90°; wear is rapidly produced at the contacts which do not vary, so that a
lengthening of the chain is caused after the chain has been in use a short time;
and further, as the wear takes place in the parts subjected to strain, breakages
frequently happen with all the inconveniences and accidents that can result
therefrom.
With the object of rendering the friction as small as possible, and consequently
of diminishing the above mentioned wear of the parts in contact, they are
frequently and abundantly lubricated; but under such conditions it is difficult to
keep the chain clean; it soils the adjoining parts, and rapidly collects dust, mud,
and other foreign matters which form a greasy mass that considerably increases
the co-efficient of friction. If there be no lubrication, then seizing is liable to take
place in a still more quickly destructive manner, and the worn parts soon oppose
an enormous resistance to movement which frequently causes either compulsory
stoppages, or breakages.
In a chain constructed according to this invention the pivots or pins are of a
peculiar form and work with a rolling motion in links formed with corresponding
holes in such a manner that the parts in contact roll one on the other after the
manner of gear teeth. Thus the resistance to angular movement of the links is
due only to rolling action and not to rubbing friction, and what is of considerable
importance, lubrication can be dispensed with, and all the drawbacks resulting
from the use of lubricant consequently avoided.
The improved chain with rolling friction is applicable generally for transmitting
motion between two parallel shafts and it can be advantageously applied to
velocipedes as will be understood from the following description.
The chain is composed of links and of short connecting pieces, both links and
connecting pieces being formed at each end with holes. The holes in the links are
cach provided internally with a tooth-like projection, and through each of these
boles passes a transverse pivot or pin which also passes through the perforated ends
The pivots are
of the connecting pieces to which they are firmly rivetted.
formed on one side with a concave surface designed to roll upon the aforesaid
projection, and on the other side with a convex surface which works in the hole of
the link.
It will be understood that the jointed parts move upon one another after the
manner of gear teeth, and consequently with the least possible friction, by rolling
contacts and without the necessity of lubrication.
In some cases each of the links between two connecting pieces may be replaced
by a number of comparatively thin links placed side by side, such links being

page_text: readily cut out by means of a punch. Similarly, there may be two or more
connecting pieces, for each pair of consecutive links.
The links may be formed with a hole at both ends or at one end only. In the
latter case each link may be made in one piece with two branches or connecting
pieces or it may be made in two pieces each having a branch or part to carry a
pivot or pin. In this case those ends of the links that are provided with teeth or
projections for making contact with the pivots or pins rivetted to the ends of the
branches or connecting pieces, are encircled by a ring which covers the break
therein, and forms a rolling surface that readily passes over the teeth of the
wheels connected by the chain.
Dated this 6th day of June 1801
L. GAUTIER,
By L. W., per F. B.
COMPLETE SPECIFICATION.
An Improved Driving Chain.
I, LOUIS GAUTIER of Saint Malo, France, Mechanician, 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:
1
This invention has reference to a construction of chain designed to transmit
rotary movement between two parallel shafts provided with gear wheels the teeth
of which enter the links of the chain.
My improved chain is of the type known as the "Galle" chain but it differs
from such a chain in several important features.
In a
"Galle" chain the links are jointed by cylindrical pins accurately fitting
holes formed in the short connecting pieces constituting the links of the chain.
With this construction friction is produced over the whole surface of the pin by
rotary or rocking movements having an angular amplitude generally smaller
than 90° wear is rapidly produced at the contacts, which do not vary, so that
lengthening of the chain is caused after the chain has been in use a short time;
and further, as the wear takes place in the parts subjected to strain, breakages
frequently happen resulting in inconveniences and accidents.
With the object of rendering the friction as small as possible, and consequently
of diminishing the above mentioned wear of the parts in contact, they are frequently
and abundantly lubricated; but under such conditions it is difficult to keep the
chain clean; it soils the adjoining parts, and rapidly collects dust, mud and other
foreign matters which form a greasy mass that considerably increases the co-efficient
of friction. If there be no lubrication, then seizing is liable to take place in a still
more quickly destructive manner, and the worn parts soon oppose very considerable
resistance to movement which frequently causes either compulsory stoppages, or
breakages.
In a chain constructed according to this invention the pivot pins are of peculiar
form and work with a rolling motion in links formed with suitably shaped holes in
such a manner that the parts in contact roll one on the other after the manner of
gear teeth. Thus the resistance to angular movement of the links is due only to
rolling action and not to rubbing friction, and, what is of considerable importance.
lubrication can be dispensed with, and all the drawbacks resulting from the use of
lubricant consequently avoided.
The improved chain with rolling friction is applicable generally for transmitting
motion between two parallel shafts and it can be advantageously applied to veloci-
pedes as will be understood from the following description.
Referring to the annexed drawings
Figs. 1 and 2 are respectively a longitudinal vertical section and a plan partly in
section of part of a chain according to my invention.

page_text: Figs. 3 and 4 illustrate in section l elevation & plan respectively a chain suitable
for a bicycle.
Figs. 5, 6 and 7 illustrate a modification.
Referring to Figs. 1 to 4, as will be seen the chain is composed of links a and of
short connecting pieces c c', both links and connecting pieces being formed at each
end with holes. The holes in the links are cach provided internally with a
tooth-like projection d, and through each of these holes passes a transverse pivot
or pin which also passes through the perforated ends of the connecting pieces c cl
to which they are firmly secured. Each pivot is formed on one side with a
concave surface designed to roll upon the corresponding projection d and on the
other side with a convex surface f.
It will be understood that the jointed parts move upon one another after the
manner of gear teeth, and consequently with the least possible friction, by rolling
contact and without the necessity of lubrication.
In the arrangement shewn in Fig. 4 some of the links a between two con-
necting pieces are replaced by a number of comparatively thin links A placed side
by side, such links being readily cut out by means of a punch. Similarly, there
may be two or more connecting pieces c, for each pair of consecutive links. As
shewn in Figs. 5 and 6 each link instead of being formed with a hole at both ends
as in Figs. 1 to 4, has a hole at one end only. In this arrangement each link
may be made in one piece with two branches or connecting pieces cc', or it may be
made in two pieces each having a branch or part to carry the pivot or pin. In
this case those ends of the links a a' that are provided with teeth or projections d
for making contact with the pivots or pins rivetted to the ends of the branches or
connecting pieces e c', are encircled by a ring g which covers the break therein,
and forms a rolling surface that readily passes over the teeth of the wheels connected
by the chain.
Fig. 7 is a detached view of one of the pivots or pins f.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is:
1. A chain constructed with links cach formed with an opening or openings such
as or having an inwardly projecting tooth such as d against which a pin / of
concavo convex form works substantially as hereinbefore described for the purposes
specified.
2. The improved chain constructed substantially as hereinbefore described with
reference to and shown in Figs. 1 to 4 inclusive of the drawings annexed, or modified
according to Figs. 5 and 6.
Dated this 5th day of March 1892.
L. GAUTIER,
By L. W., per F. B.