IMPROVEMENTS IN CHAINS FOR DRIVING OR RECEIVING MOTION FROM WHEELS OR PULLEYS AROUND WHICH THE CHAINS ARE MADE TO PASS
Year: 1881

page_text: LETTERS PATENT to Francis Ley, of Derby, in the County of Derby, for
an Invention of "IMPROVEMENTS IN CHAINS FOR DRIVING OR RECEIVING
MOTION FROM WHEELS OR PULLEYS AROUND WHICH THE CHAINS ARE MADE
TO PASS."
A communication from abroad by James Mapes Dodge, of
Chicago, in the United States of America.
PROVISIONAL SPECIFICATION left by the said Francis Ley at the Office of
the Commissioners of Patents on the 28th January 1881.
FRANCIS LEY, of Derby, in the County of Derby. "IMPROVEMENTS IN
CHAINS FOR DRIVING OR RECEIVING MOTION FROM WHEELS OR PULLEYS AROUND
WHICH THE CHAINS ARE MADE TO PASS." A communication from abroad by
Jaunes Mapes Dodge, of Chicago, in the United States of America.
This Invention has for its object improvements in chains for driving or receiving
motion from wheels or pulleys around which the chains are made to pass.
It is usual in the use of driving chains to cause the chains to engage with teeth
or projections on the wheels or pulleys. In place of teeth I provide the wheels or
pulleys with V grooves in the periphery, and I provide corresponding projections
upon the links of the chain.
The link which I usually employ is of an open rectangular form, and is provided
at one end with a hook by which it engages with the cross bar of the link in front;
in a certain position of the links they can be hooked and unhooked at pleasure.
The projections to enter the V grooves of the wheels or pulleys I form upon the
under sides or the hooks of these links. In chains of large size each link may be
provided with two projections, one on either side.
The links carrying the inclined projections may be of other forms, and in some
cases the sides of the links may have the inclines upon them, the body of the chain
then entering into the groove of the wheel or pulley. In some cases the periphory
of the wheel or pulley may be formed with a taper projection or projections in place
of a groove or grooves, and in this case the links are provided with corresponding
inclined grooves or notches.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Francis Ley in the Great Seal Patent Office on the 27th July
1881.
FRANCIS LEY, of Derby, in the County of Derby. "IMPROVEMENTS IN
CHAINS FOR DRIVING OR RECEIVING MOTION FROM WHEELS OR PULLEYS AROUND
WHICH THE CHAINS ARE MADE TO PASS." A communication from abroad by
James Mapes Dodge, of Chicago, in the United States of America.
This Invention has for its object improvements in chains for driving or receiving
motion from wheels or pulleys around which the chains are made to pass.
It is usual in the use of driving chains to cause the chains to engage with teeth
or projections on the wheels or pulleys. In place of teeth I provide the wheels or
pulleys with V grooves in the periphery, and I provide corresponding projections
upon the links of the chain.
The link which I usually employ is of an open rectangular form, and is provided
at one end with a hook by which it engages with the cross bar of the link in front;
in a certain position of the links they can be hooked and unhooked at pleasure.
The projections to enter the V grooves of the wheels or pulleys I form upon the
undersides of the hooks of these links. In chains of large size each link may be
provided with two projections, one on either side.
The links carrying the inclined projections may be of other forms, and in some
cases the sides of the links may have the inclines upon them, the body of the chain
then entering into the groove of the wheel or pulley. In some cases the periphery
of the wheel or pulley may be formed with a taper projection or projections in
place of a groove or grooves, and in this case the links are provided with corre-
sponding inclined grooves or notches.
In the Drawings hereunto annexed I have shewn examples of driving chains
constructed according to this Invention. Figure 1 is a side view and Figure 2 is
a top or edge view of a drive chain and a pair of chain wheels arranged relatively
in a working condition and embodying the principle of the Invention.
Figure 3 is a vertical section at the line x, x, of Figure 1, and Figure 4 is an
edge view of two of the chain links detached and made on a larger scale for the
purpose of more clearly shewing the detailed construction thereof."
Figure 5 is a sectional view (similar to that seen at Figure 3) of a chain and
wheel, but shewing a modification of the Invention, in which the chain link is of a
different form from that shewn in the four preceding Figures, and in which the
face of the wheel used has two grooves instead of one, the portion of its periphery
embraced between its grooves forming a wedge shaped rib, as it were, that acts
between the adjacent edges of the two tapering lugs of the chain link.
Figure 6 is a bottom view, and Figure 7 is an end view of a link such as shown
in cross section at Figure 5.
At Figure 8 I have shewn a vertical cross section, still another modification of
the Invention, in which the face of the wheel has one very wide groove or
depression forming two tapering annular bearing ribs near the edges of said face,
adapted to receive the tapering lug like bearers on the opposite sides of the link of
a chain formed of alternate single and double-bar links.
Figure 9 shews in top view, and Figure 10 in edge or side view this form of
chain.
At Figures 1 to 4 inclusive, A and B are two wheels mounted in a usual manner
on their respective shafts C and D, and either of which may be assumed to be
that from which power and motion are to be transmitted to the other through the
medium of the drive chain E.

page_text: This chain, as shewn, is composed of detachable open links of rectangular
contour made after the fashion of what is well known in the market as the
"Ewart" detachable drive-chain.
Each of the said wheels has formed in its periphery or working face a sort
of V shaped groove or channel f running circumferentially of the wheel face, and
the working surface of the chain (that face of the chain which works against the
wheels) is formed or provided with a series of projections g, one to each link, each
of which is slightly tapering in form (in one direction) so as to correspond to the
taper of and to fit into the groove in the manner shewn (see Figure 3), without
having its end reached quite to the bottom or root of the groove f
It is desirable to have the plane of the lugs or projections g that work in the
groove finclined from a right angle to the plane of the link sufficiently to cause
said projections to lie when in the groove f in planes about coincident with the
radii of the wheels on which the chain is intended for.use.
Of course in cases like that illustrated, where the chain has to run on different
sized wheels, the inclination just referred to of the lugs g cannot be such as to
cause them to lie (while working in the grooves of the wheels) in planes exactly
coincident with the radii of both wheels, but they can be made to approximate to
this condition relatively to each wheel.
The essential conditions however of these tapering lugs g relatively to the
tapering groove fare, first, that the taper of the edges of the lugs and that of the
sides or walls of the groove shall, when the lugs are working in the grooves,
correspond sufficiently well, and that the bearing surface of each lug shall be
sufficiently narrow in the direction of the length of the chain to cause the lugs to
act with a proper wedge like tendency against the sides of the grooves and take a
bite therein, and that the grooves be somewhat deeper than the projections g
are long, so that the parts may wear away considerably (at their tapering surfaces)
without having the wedge like tendency or action of the lugs within the grooves,
and the grip of the edges of said lugs on the sides of said groove destroyed by an
abutment of the ends of the former against the bottom of the latter.
In practice the weight of the chain being comparatively so much greater than
that of an ordinary belt or pulley band, it has been found that with the drive
chain exceedingly slack (that is in a condition in which but for its gravity the
chain would not be taut enough to avoid a slip on the wheels), a sufficient grip of
the tapering lugs on the bearing surfaces of the V shaped groove is created to
render the contrivance successfully operative for most purposes.
The general operation needs little or no further explanation.
Either wheel being rotated the power and motion desired to be transmitted is
conveyed through the medium of the chain belt to the other wheel and its shaft;
and the shown and described principle of construction of chain may of course be
applied under a great variety of sizes and mere modifications of the details of the
parts composing the contrivance.
For instance, in lieu of the form of chain and wheel face shown at Figures 1 to 4
inclusive, and so far particularly described, the wheel and chain links may be
made, as seen at Figures 5, 6, and 7, where the face of the wheel has two
circumferential grooves at f³, f, and the chain link has two correspondingly
tapering lug like devices g², g², each of which engages with or takes hold in one of
said grooves.
In practice I have found this form of wheels and chain devices to work exceed-
ingly well even on large sized chain links, the edges of the biting lugs g², g², being
made quite narrow and their taper being comparatively slight.
Or under still another modification of my Invention the form of wheel, face, and
chain seen at Figures 8, 9, and 10, may be employed, wherein the face of the pulley
has two circumferentially arranged ribs h², h, the adjacent faces of which are
slightly tapering, as shown, having a broad groove or depression between them, and
in which the chain shown is composed of alternate single and double bar links, the

page_text: exterior sides of the bars of each double bar link having narrow lug like pro-
jections 2,2, adapted to have their tapering edges bear against and grip the
tapering surfaces (between which the link is wedged) of the ribs h³, h², of the
wheel.
In any of the various forms in which this Invention can be practiced, the lug
like devices, the narrow edges of which grip the bearing surfaces (of the wheel)
against which they are forced, may be applied singly or in pairs to each side or
edge of each link or only to some of the links of the chain according to the sizes of
the wheel and chain and as in the judgment of the constructor the designed
character of the work to be done may demand they should be arranged.
Other forms in which my Invention may be practiced and different modes of
carrying it out that have not yet occurred to my mind may of course be suggested,
but it will be fully understood from what is herein shown and described that the
essential character of my Invention rests in the employment on a metallic drive-belt
of devices having sufficiently narrow and slightly tapering bearing surfaces adapted
to wedge into and take a grip or bite on the tapering bearing surfaces (of the wheels'
face), between which said devices are wedged.
It will be seen that by reason of the inevitable (but practically unobjectionable)
slip now and then of the chain on the peripheries of the wheels and the practical
impossibility of running the parts together, so that the chain lugs will always bear
at precisely the same points along the line of the groove or bearing surfaces of the
wheel both the lugs and groove will wear away evenly together and maintain a
sufficient perfection of fit to each other to insure a continued perfection of operation
in the contrivance.
And it will be understood that the capacity of the chain and wheels periphery to
slip on each other under extraordinary or unusual strain really renders the con-
trivance exceedingly better than drive-chain and chain-wheel contrivances, in
which the parts positively interlock, since with the capacity created by this
Invention the chain (like an ordinary belt) can slip in case of undue strain, thus
preventing any injury to the machine; while in the use of drive-chains and wheels
as heretofore made and used, in case of any extraordinary strain on the con-
trivance, the chain or the sprocket-wheel (or both) must either be broken. or
otherwise injured.
I am aware of the fact that it has long ago been suggested to employ in
connection with wheels having V shaped grooves in their peripheries chain like
driving bands composed of metal links made wedge shaped all along their sides, or
having attached to them (in some cases at the sides and in others at the backs of
the links) wedge shaped devices composed of wood or leather or other analogous
materials, and adapted to engage by frictional contact with the tapering surfaces
of such grooves in said wheels, and that patents have been granted for such
contrivances.
All such contrivances differ materially from this Invention as well. in practical
operation and effect as in the mechanical principles involved.
Chain links formed according to this Invention have the wedge-like projections
formed in one piece with them, and the projections are made narrow, as their
effectiveness depends upon the reduction of the extent of the surfaces of contact
between them and the wheel to the smallest practical extent, the efficiency of action
depending upon having the surface of each tapering bearing lug of the chain so
narrow that it will occupy a space on the wheels' face so short in the direction of
the circumference of the wheel as will be practically a straight or flat surface.
Having thus described the nature of the Invention and the manner of performing
the same, I would have it understood that I claim,—
First. The construction of driving chains substantially as herein before described
and illustrated in the Drawings annexed.
Second. The construction of driving chains of links having projections standing
out from and formed in one piece with them, such projections being made narrow

page_text: as compared with and in the direction of the length of the link, and shaped to
enter into a V groove or grooves or fit over a V projection or projections formed
around the circumference of a wheel, substantially as herein before described.
In witness whereof, I, the said Francis Ley, have hereunto set my hand and
seal, this Twenty first day of July, in the year of our Lord One thousand
cight hundred and eighty one.
FRANCIS LEY. (L.S.)