Improvements in Eccentric or Crank Mechanism for Transmitting Motion or Power.
Year: 1897

page_text: Date of Application, 26th Oct., 1897-Accepted, 12th Feb.,
1898
COMPLETE SPECIFICATION.
Improvements in Eccentric or Crank Mechanism for Transmitting
Motion or Power.
I, SAMUEL WALKEY GILLETT, of the Firm of H. B. Barlow & Gillett, of 17,
St. Ann's Square, Manchester, Registered Patent Agent (which invention has
been communicated to me by John George Wagner, Junior, of 189, Brown Street,
Rochester, New York, U.S.A., Manufacturer, and Herman Samuel Searle, of
466, North Clinton Street, Rochester, aforesaid, 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 relates to devices for transmitting motion or power from one shaft
or revolving part to another without the use of chains, belts, shafts, toothed wheels,
or other similar intermediate devices commonly used for the purpose, it being such
also that there shall be no dead centres or points in a revolution where the applied
power is momentarily ineffective.
The invention consists in providing an eccentric or crank for the driving shaft
or revolving part, a similar bearing for the driven part, and a pivotal connector for
said bearings whereby when the driving part is made to revolve, by any means, the
driven part will also revolve in the same time but in the opposite direction.
as
3 in
The invention is hereinafter fully described and more particularly pointed out.
Referring to the accompanying drawings, Figure 1 is a side elevation of the
device, showing eccentric bearings, parts being broken away and other parts shown
Figure 2 is a similar
in various positions by full and dotted lines.
view with many parts omitted, the frame being in longitudinal section.
indicated by arrow
Figure 1.
seen
a plan,
Figure 3 is
Figure 4 is a transverse section on the dotted line 44 in Figure 1. Figure 5 is a
side elevation at the middle of the connector. Figure 6 is a transverse section
through the axis of the connector. Figure 7 is a side elevation showing crank
motions. Figure 8 is a plan, seen as indicated by arrow 8 in Figure 7. Figure 9
is a longitudinal section on the dotted line 99 in Figure 8, showing the connector.
Figure 10 is a transverse section on the dotted line 10 10 in Figure 8. Figures 11
and 12 show the manner of attaching rims of different kinds and diameters to the
main driven axle. Figure 13 shows the trunnion pin of the connector. Figures 14
and 15 show how a band pulley or a grooved pulley may be substituted in place
of the cogs.
According to this invention I form a frame A, preferably of steel, composed of a
long member d, and a short member c, held side by side by simple fasteners k.
Or, if preferable, the parts may be formed in one piece, as shown in Figures 7 and 8,
and connected by raised cross-ties k¹ k¹. A rotatory driving shaft or axle C, is
held transversely at one end of the frame and provided with an operating crank H.
Another shaft or axle, B, is held transversely at or near the other end of the frame
to be operated indirectly by the driving crank H, the axis of said shafts or axles
being parallel and in a plane.
The shaft C is provided with an eccentric bearing E, and the shaft or axle B is
provided with an eccentric bearing D, both eccentric bearings are in a plane

page_text: perpendicular to the axis of said axles C and B. Or, if cranks are used instead of
eccentrics, they are preferably made double, as shown at D' and B', in Figures 7
and 8.
F is a connector for the cranks or the eccentrics, provided with a central sliding-
head G, Figures 1-4, adapted to move longitudinally along parallel parts a a of
the frame and between the two members thereof. The sliding-head is commonly
formed of two parts, e e, joined, between which the connector is pivoted upon a
transverse pin f, Figure 6, the axis of which pin is parallel with the axis of the
axles B and C. The two parts of the sliding-head meet between the members of
the frame, at the line 1, Figures 3 and 4, one of their meeting faces being shown
at m, Figure 2. Simple screws or pins, n n, are employed to hold the parts of the
head together.
When the eccentrics are used the connector F is usually made in the form of an
open frame or truss, having a middle tie or cross-bar, o, Figures 4, 5 and 6,
spanning the space between the joined parts e e of the sliding-head.
The connector is joined to the eccentric bearings D and E, respectively, by
means of rings or end pieces g and h, held at the ends of said connector. These
end pieces may be joined to the main central part of the connector by simple means,
or they may be in one piece with the connector. It is more convenient, however,
to make the end pieces separate, as shown, and join them to the main piece.
It is preferable in most cases where the eccentrics are used, to supply the bearings
with balls, i, as shown in Figure 1, for the purpose of decreasing the friction
between the parts. These balls are introduced into the ball races, r, of the bearings
through openings p, in the end pieces g and h. These openings communicate
directly with the races, and when the end pieces are secured to their places on the
main part of the connector said openings are thereby closed so the balls cannot
escape.
connector may have both
Said head and pin serve
move backward and for-
shafts or axles C and B,
This pivotal motion of
dead centers" which
By means of the sliding-head G and the pivot pin f the
a sliding motion and a rocking motion upon the frame.
to control the middle part of the connector and hold it to
ward practically in a right line between the axes of the
while its ends turn in circles as the eccentrics revolve.
the connector prevents the occurrence of what is known as
commonly attend this class of machines or devices, in which rotatory and reciprocal
parts co-act.
In case the cranks B' D' are used instead of the eccentrics the connector may be
much smaller or narrower, as shown in Figures 8 and 9, the trunnion pin f being
held rigidly therein at the middle point of the connector. In this case the frame A
is formed with opposing longitudinal slots d¹ d¹, Figures 7 and 10, for the accom-
modation of the trunnion pin. The axis of this pin intersects at right angles the
axis of the connector, the pin projecting equally at either side through the
respective slots d'd in the frame. Preferably the projecting parts ¹ of
the trunnion pin are provided with anti-friction rollers, ff, adapted to roll in the
slots while the connector is moving longitudinally, said slots forming guides or
tracks for controlling the middle part of the connector. These slots are provided
with adjacent horizontal ledges, ol o¹, projecting at the sides of the frame, which
serve to broaden the surfaces of the tracks along which the rollers travel.
These rollers are held to place by means of screws, gl g¹, threaded in the ends of
the pin, retaining washers, h¹ h¹, being provided to control the rollers. The ends
of the pin are preferably reduced to receive the washers h¹¹, the screws serving to
hold the washers against the shoulders on the pin so as to leave the rollers free to
turn upon the pin. The trunnion pin thus provided and environed serves as a
fulcrum or pivot upon which the connector turns or rocks as its ends are carried
around in circles by the cranks.
The gear I, as appears in Figure 7, is preferably formed with a hub and arms ll¹
holding a detachable rim m¹. This rim may be toothed, as shown, or it may be
formed with a face upon which to receive a flat belt, as shown in Figure 14, or to

page_text: receive a cord, as shown in Figure 15. By these means motion may be con-
veniently communicated to other mechanisms or devices, as may be required. The
rim whatever its form or kind is secured to the arms by simple means, as bolts n¹,
the rim having inwardly projecting short arms to meet the arms . When the
device is used to propel a bicycle the latter may be geared at a high or low speed
by using toothed rims m¹ of a greater or less diameter secured to the arms, as
shown in Figure 11.
The pin b, Figures 7 and 9, of the crank D' is carried by a plate or block cl rigid
with the arms of the wheel or spider I, said plate or block and the associated arms
of the wheel constituting integral parts of the crank.
As to the actions of the various moving parts it will be noted that when the
driving crank H is horizontal, as shown in Figures 1 and 7, and the parts are all
in line, the connector F will, if the crank be moved downward, act momentarily
purely as a lever of the first order. But this lever-action of the connector will
gradually decline until the crank stands vertically downward when the connector
no longer acts as a lever but acts, rather, to deliver a direct endwise push or thrust
against the bearing at its opposite end. As the crank moves onward the thrust-
pressure or action of the connector declines, and wholly disappears when the crank
has made a half revolution. Continuing the motion of the crank the connector
again acts as a lever of the first order which characteristic wholly disappears again
when the crank reaches a vertically upward position.
Now as the crank moves
toward the starting point the connector will exert momentarily a direct endwise
pull at its farther end which pull declines and wholly disappears when the crank
again reaches its original position.
Or, briefly stated, at the beginning of the first quarter revolution the connector
acts as a lever; at the beginning of the second quarter it acts to deliver a direct
push at the beginning of the third quarter it again acts as a lever, and at the
beginning of the fourth quarter it exerts a direct pull.
From this it will be understood that the action of the driving upon the driven part
is continuously effective throughout a complete revolution and no dead centers can
occur, the pivotal actions of the connector serving to prevent them.
It is evident that any device may be connected with the driven axle B according
to the use to which the machine is put or the work to be done. As shown, a spur
gear I is made rigid with said driving axle and a pinion, K, in mesh with the gear,
the pinion being rigid on the shaft L which shaft may be, for example, the rear
axle of a bicycle.
The form of the frame A is not essential, its use being to hold the parts in place
the device, as shown, being more particularly adapted for use with bicycles for
the purpose of doing away with the ordinary chain. When applied to this use the
pedal-cranks are secured to the axle C, the direction of motion of said axle and the
pinion K being the same, while the motion of the gear I is opposite.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a device for transmitting motion or power, a rotatory driver formed with an
eccentric or crank bearing, and a rotatory driven part having a similar eccentric
or crank bearing in combination with a connector for said bearings and means for
supporting the connector at mid length in such manner that it is capable of a
pivotal oscillating as well as a reciprocal sliding motion whereby the action of the
driving upon the driven part is continuously effective throughout a complete
revolution.
2. In a device for transmitting motion or power, the combination with a rotatory
driver formed with an eccentric or crank bearing and a rotatory driven part having
a similar eccentric or crank bearing, of a connector for said bearings mounted and
supported so as to be capable of rocking and sliding movements whereby the con-
nector at the beginning of the first quarter revolution acts as a lever, at the beginning

page_text: of the second quarter it acts to deliver a direct push, at the beginning of the third
quarter it again acts as a lever, and at the beginning of the fourth quarter it exerts
a direct pull.
3. In a device for transmitting power or motion, a rotatory driver formed with
an eccentric bearing and a rotatory driven part having an eccentric bearing in
combination with a connector for said bearings having pivotal motion between
the bearings substantially as described.
4. In a motion or power transmitting device, a rotatory driver formed with an
eccentric bearing and a rotatory driven part having an eccentric bearing in com-
bination with a connector for said bearings and means to cause the middle part of
said connector to have a reciprocating sliding motion substantially as set forth.
5. In a device for transmitting motion or power in combination with a frame, a
driving crank and a driven crank held by the frame, a pivoted part connecting said
cranks, guides in the frame for said pivoted parts, and a wheel controlled by said
driven crank, formed with projecting arms or parts adapted to receive rims of
different diameters substantially as specified.
6. In a device for transmitting motion or power, the combination with a two-
part frame the central portion of which is provided with a parallel portion, a shaft
at each end of the frame provided with an eccentric, a head between the parts of
the frame, each part of said head being provided with means for engaging with the
parallel portions of the frame, a pin in the head an open frame connector provided
with a cross bar pivotally secured upon the pin the ends of the connector being
connected with the eccentrics substantially as set forth.
7. In a device for transmitting motion or power, the combination with a frame,
of a shaft journalled at each end thereof, an eccentric upon each shaft, a head upon
the central portion of the frame, a connector pivotally secured to the head and
having its ends connected with the eccentrics, each end of the connector having an
opening leading into the space between the eccentrics and the connector and balls
within the space substantially as set forth.
8. In a device for transmitting motion or power, the combination of a frame
having opposing longitudinal slots in the sides thereof and a double crank at each
end of the frame, a connector joining the two cranks, a pin through the connector
the ends of which are provided with projections and rollers upon the projections
within the slots, substantially as set forth.
9. In a device for transmitting power or motion, the combination with a frame,
of a double crank at each end thereof, a portion of the crank at one end being pro-
vided with a rim forming a wheel, and a connector joining at each end with the
cranks and movably connected with the frame at its centre substantially as set
forth."
10. The several combinations and arrangements of parts embodying the herein
described improvements in devices for transmitting motion or power substantially
as specified and as illustrated by the accompanying drawings.
Dated this 25th dose of Ontahan 1007
H. B. BARLOW & GILLETT,
Agents for Applicant, 17, St. Ann's Square, Manchester.