Improvements in and relating to Driving Mechanism especially suitable for Bicycles.
Year: 1898

page_text: Date of Application, 13th Sept., 1898-Accepted, 25th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in and relating to Driving Mechanism especially
suitable for Bicycles.
We, HOSER TUTTLE, of No. 613, Fifth Street, in the City of Cedar Rapids,
County of Linn and State of Iowa, United States of America, Mechanical Engineer,
and SHELLEY TUTTLE, of No. 959, East Second South Street, Salt Lake City, in the
County of Salt Lake and State of Utah, United States of America, Gentleman,
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:-
Our invention relates to mechanical movements intended mainly for the pro-
pulsion of bicycles, to take the place of the chain now generally used on safety
bicycles, and thereby reduce the expense and the amount of friction.
Although the construction of the movement can be used in connection with
other machines, it is shown in the drawing in connection with a bicycle, the
frame of which may be of any suitable form. It comprises cranks and crank-
pins on the axle of the hind-wheel, sprocket wheels on the axle of the pedal
shaft and forked connecting rods to unite said axles, but in this improvement
the location of the hind cranks is within the side frame, the interlocking sprockets
are provided with anti-friction rollers, and the ends of the forked connecting
rods are provided with hooked or open jaw connections adapted to rock in said
ends, each one of said hooked rocking connections having a segmental outer
periphery adapted to roll back and forth upon plane horizontal surfaces of the
frame acting as guides, or simply an arm provided with a pivotal support, the
rocking of the connections facilitating the noiseless entrance of the sprocket
rollers into said hooked connections and their issue therefrom, and also to com-
pensate for the inequalities of speed of the connecting rods due to the rear crank's
motion, and thus obtain uniform motion of the sprocket wheel. Other new
features will be described in connection with the accompanying drawings in
which
Figure 1 represents a side view of a bicycle provided with a mechanism con-
structed in accordance with our invention, but showing only one of the forked
connecting rods.
Figure 2 represents on a larger scale a top view partly in section of the
mechanism.
Figure 3 represents a side view of the mechanism on one side of the machine
with the casing of the sprocket wheel in section, the rear wheel crank being in
its rearmost position.
Figure 4 is a similar view, with the sprocket wheel omitted and the rear wheel
crank in its foremost position.
Figure 5 represents on a larger scale a transverse vertical section of the
mechanism on a line passing through the crank shaft.
Figure 6 is a horizontal section of the pedal crank shaft casing in a reversed
position, showing a portion of the mechanism therein.

page_text: Figure 7 represents on a still larger scale the upper bolt of the inner frame
carrying the links of the hooked or open jaw connections of the forked con-
necting rods.
Figure 8 is a section of one of the hooked or open jaw connections.
Figure 9 is a side view of the two sprocket wheels and their connecting hub
having T-headed arms to provide bearings for the friction rollers located on
one side 30° in the rear of the opposite side.
Figure 10 is an enlarged view of the upper half of Figure 3.
Figure 11 is an end view of the cranks of the rear wheel.
Figure 12 is a side view of one of the split eye bearings of the pedal crank shaft
and its clamping bolt.
Figure 13 is a transverse vertical section, of a construction slightly modified
from that shown in Figure 5.
Figure 14 is a side view on a smaller scale of the construction shown in
Figure 13, the casing being in section.
Figure 15 is a horizontal section through the rear end of one pair of the
forked or modified divergent connecting rods on one side of the machine.
Figure 16 is a horizontal section through the rear end of one member of
a pair of connecting rods.
Figure 17 is a vertical section of one of the open jaw connections used with
the modified construction shown in Figure 13.
Figure 18 is an enlarged view of the upper half of the frame and the parts
shown in Figure 14.
In said drawings A represents the forked seat-carrying standard of the frame
and A2 the braces between the crank shaft carrying the pedals 132 and also the
sprocket wheels C and C2, and the crank-axle d, which is tubular in part and
constitutes the hub of the hind wheel E, said axle d has its ends received in
ball-bearings a mounted in the rear ends of the braces A2 and protected by
caps a which are screwed upon the outer cone of said ball bearings and bear
against the frame A2 and thus serve also as a lock-nut for the ball-ways.
Each end of the axle d has a crank arm, and each end of the hub of the
wheel E has a similar crank arm e² but the arms are set at an angle of 90°
to each other. The arms d², e2 of each crank are united by a tubular crank pin D
having four lugs provided with side faces that are not radial but are parallel and
at right angles to each other, and are projecting from each one of its ends, that
are received in corresponding grooves formed at right angles to each other in
bosses on the arms d² e², and a bolt D2 passing through said arms and through
the crank-pin secures these parts together until it is desired to remove the
wheel E for repairs. The pin D is grooved circumferentially to obtain a ball-
bearing way to receive the inner face of the balls of the ball-bearing around it
and said balls are enclosed by the eye in the rear end of each forked connecting
rod.
The double sprocket wheel is located in the center of the length of the crank
shaft of the pedals and consists preferably of two skeleton triangular plates C
and C2, each having its angular ends or sprockets cat equal distances apart,
but the sprockets of one wheel are so timed relatively to the sprockets c of the
other wheel as to be about thirty degrees in the rear of each one of them. Between
the triangular plates, there is a carrying hub having three T-headed arms,
and the ends of said arms constitute one of the supports for the bearing pin of
each roller r, of the sprocket wheels while the arms of the sprocket wheels con-
stitute the other support for the end of said bearing pin, the ends of said arms
being outwardly bent for the accommodation of the rollers r. The hubs of the
sprocket wheels C C and of the middle hub-plates c2 constitute together a com-
pound sprocket wheel, which is secured with bolts to a circular collar projecting
from a sleeve 6 screwed on the inner ends of the two parts of the crank shaft b.
Said sleeve has secured upon each one of its ends the inner ring 7 of ball bearings.
while the cones 8 of the outer ring of said bearing are screwed to the inner face

page_text: of the eye or bearing box 9 uniting the braces A and A². The outer portion of
the bottom of said eye is split and its ends united together by a bolt 18 to clamp
the cone rings.
To the inner face of each eye 9 is secured a rectangular frame 10 of stout
sheet metal cut out of skeleton form, for lightness; the means of attachment
being an arm 11 extended radially from said eye 9, and a bolt 12 passing through
said arm and screwed into the frame 10. The two frames 10 in Figures 5 and 7
are connected to each other at each corner by means of bolts 13 passing through a
series of short sleeves 14 upon which one end of links 15 are pivotally mounted.
To the opposite end of each one of said links are pivotally attached the rocking
jaws feach one of which has a slot f to receive one of the rollers r of the sprocket
wheels.
To connect each rocking jaw f with the front ends of each branch of the forked
rods For G, each front end has a large eye within which ball bearings are
placed, and to the circular inner cone of said bearing is secured an arm which
is parallel with the jaw f2 and integral therewith but is at a short distance from
said jaw to permit the edge of the sprocket wheel to pass between them while
its roller, enters into the jaw. Each rocking jaw is supported by a link 15
as above stated. The outer periphery of each jaw is in the form of a segment
of a circle around which it rocks, upon the edge of horizontal guide plates 16.
The ends of said plates are mounted upon the bolts 13, and the inner faces of each
pair of guide plates serve as guides for the sides of the jaw f2. The rocking
edges on the sides of each jaw fare preferably made of hardened steel and are
of slightly less diameter then the segmental body of the jaw, and thus the back
of the jaw is well supported, both on its periphery and on its sides. For clearness
only one jaw is shown in engagement with the sprocket wheel in Fig. 5 and in
practice there is only one or a portion of two jaws; but the construction of ball
bearings and jaws is repeated for each branch of the forked connecting rods ou
both sides of the machine. The sides of the slot f of each working jaw are
lined with hard steel face plates dovetailed in said sides.
The distance between the front ends of the branches of the forked rod F
is maintained by a brace F2 uniting said branches and they are supported by
the segmental back of the jaw f2 and the latter by the links.15 and the guide
plate 16. The sprocket wheel and the parts adjoining are inclosed in a casing 3.
to keep out dust and dampness. Said casing may be of wood, metal, celluloid or
glazed leather or may be of oil cloth stretched over wires. Said casing has in
its rear edge two openings on each side for the passage of the forked connecting
rods For G, and said openings can be rendered dust-proof and damp-proof by
means of flexible diaphragms of thin rubber or textile material which may be
secured around each opening to the casing and its center made to clasp each branch
of the forked connecting rod. Surrounding the ends of the sleeve 6 of the pedal
shaft, within the outer cone-ring 8, felt-washers 17 are placed to prevent the
admission of dust at these points. Collars 5 upon the sleeve 6 prevents the ball-
bearings from spreading.
The double face sprocket wheel C C is secured to the collar surrounding said
sleeve 6 by means of three small bolts and the three parts from which said wheel
is made are bolted together at suitable points between the hub portion and the
ends of the arms carrying the rollers r, the relative position of the arms on one
side being about thirty degrees in the rear of each arm on the opposite side, and
as the double faced sprocket wheel is completely built before mounting it on the
shaft, there is no danger of defect of adjustment relatively to its proper position
on the shaft.
The frame of the machine is provided with a forward forked brace As located
as usual.
In the modified construction shown on Sheet 3, Figures 13 to 18, the two
frames 10 are bent inwardly and connected to each other at the top and bottom
by means of bolts 13 passing through said frames and screwed into the ends

page_text: of short sleeves 14, the inner periphery of which has ball-ways for the balls of
the ball-bearings carried in the pivoted outer ends of the body of the jaws f²
each one of which jaws has a slot f to receive one of the rollers r of the sprocket
wheel. Within the pivotal outer end of each jaw is fitted one member f* of the
inner cone, the other member fo being adjustably connected with the member f*
by a central screw f and a locking pin f.
The rear ends of each branch of each forked connecting rod For G are indepen-
dently pivoted on the crank-pins of the shaft of the rear wheel, and are part way
overlapping each other, as generally found at the hinge of scissors, to permit
them to have a slight amount of rotation at that point independently of each
other, to compensate for the slight curvature of the arc traveled by the swinging
jaws on their pivots.
In the operation of the machine the rocking up and down and also longitu-
dinally of the rear end of the connecting rod F or G causes the jaw connec-
tions at their front ends to be rocked upon their guide-plates 16 and their
slotted or jaw portion to be presented in the best positions to either receive one
of the rollers of the sprocket wheel, or to let one of said rollers escape from
engagement with the sprocket wheel, so that the engagement of the parts will
be noiseless.
As
As there must necessarily be some moments in which the rollers of one of the
sprockets on one side are not in working engagement with the slots of the rocking-
jaws (while entering and leaving them), a duplication of the mechanism is
required to actuate the rear crank axle during the intermediate movements.
there is only a little more than one roller of the sprocket-wheel, or a portion
of two rollers in engagement with the rocking jaws on the ends of the forked
connecting rods, the friction is reduced to the minimum possible.
The diameter of the sprocket wheels and the number of arms they are to carry,
or the diameter of the carrying wheels can be selected according to the speed
of motion that may be desired.
In our Patent Specification No. 21350 of 1897 we showed and described driving
mechanism with two separate sprocket wheels on the crank axle. The advantage
derived from having substantially only one sprocket wheel, and that, in the axial
line of the machine, is that there is no possibility of having the two separate sprocket
wheels dislocated relatively to each other at 30° upon the shaft, the pull on them
being alternate. And by having them in the axial line, the pull and push is
equal between the bearing boxes, and only one casing is required to protect the
parts from dust.
As the sprocket wheels are mounted on a sleeve having its ends
bearing directly in a bearing box, and it is in effect a solid piece with the cranks
screwed therein, the danger of springing the crank-shaft is materially removed,
and also the danger of springing the sprocket wheels.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is-
1. In a bicycle the combination of an axle carrying two crank-pins, a forked
connecting rod mounted at one end upon each crank-pin and having at the opposite
end open jaw connections pivotally mounted thereon, a frame and links supporting
said connections, and sprocket wheels having friction rollers for engagement
with the jaws of said connections, substantially as described.
2. In a bicycle the combination of the axle of one of the carrying wheels, two
crank pins carried by said axle, two branched connecting rods mounted at one
end upon each crank-pin and having at the opposite end two open jaw connections
pivotally mounted thereon, each jaw connection having a segmental outer periphery
guide plates having their edge serving as a track for the segmental periphery of
the jaw to rock upon and a frame' carrying said guide plates, substantially as
described.
3. In a bicycle the combination of the axle of one of the carrying wheels,

page_text: two crank-pins carried by said axle, two branched connecting rods mounted at one
end upon each crank-pin and having at the opposite end two open jaw connections
having a segmental outer periphery longer in its centre than on its cheeks,
guide plates having their inner faces guiding the sides of the jaw connections
and their edges guiding the edges of the cheeks of the jaw connections, and a
frame carrying said guide-plates, substantially as described.
4. In a bicycle the combination of the axle of one of the carrying wheels,
two crank-pins carried by said axle two branched connecting rods mounted at one
end upon each crank-pin and having at the opposite end an open eye, ball-
bearings in said eye consisting of outer cones, inner cones and interposed balls,
and an open jaw connection having a side arm secured to one of the inner cones,
substantially as described.
5. In a bicycle the combination of the axle of one of the carrying wheels, two
crank pins carried by said axle, two branched connecting rods mounted at one end
upon each crank-pin, an open jaw connection pivotally mounted upon each branch
of said rods, the pedal crank-shaft and a pair of sprocket wheels centrally mounted
upon said shaft, substantially as described.
6. In a bicycle the combination of the axle of one of the carrying wheels,
two crank-pins carried by said axle, two branched connecting rods mounted at
one end upon said crank-pin, an open jaw connection pivotally mounted upon
each branch of said rods, the pedal crank-shaft, a sleeve mounted upon said shaft,
and a pair of sprocket wheels mounted upon said sleeve centrally of its length,
substantially as described.
7. In a bicycle the combination of the pedal crank-shaft, a sleeve mounted
thereon, an inner cone ball-bearing mounted upon each end of said sleeve, a
series of balls, outer cone ball bearings, and the frame of the bicycle having
eyes receiving said outer cones, said eyes being split between lugs thereon and
said lugs bolted together, substantially as described.
8. In a bicycle the combination of the axle of the rear carrying wheel, two
crank-pins carried by said axle, two branched connecting rods mounted at one
end upon each crank-pin, the pedal crank-shaft, its sleeve, a pair of sprocket-
wheels upon said sleeve, the frame of the machine, a secondary frame on each
side of a pair of sprocket wheels, rods connecting together the secondary frames,
links pivotally mounted upon said rods, and open jaw connections mounted upon
said links, substantially as described.
9. In a bicycle, the combination of the axle of the rear wheel carrying two
crank pins, two divergent connecting rods mounted at one end upon each crank
pin, each having at the opposite end an open jaw connection pivotally mounted
thereon, a frame supporting said connections and a sprocket wheel having friction
rollers for engagement with the jaws of said connections, substantially as described.
10. In a bicycle, the combination of the axle of one of the carrying wheels,
two crank-pins carried by, said axle, two divergent connecting rods mounted
at one end upon each crank-pin, each having at the opposite end an open eye,
ball-bearings is said eye consisting of outer cones, inner cones, and interposed
balls, and an open jaw connection having a side arm secured to the inner cone,
substantially as described.
11. In a bicycle, the combination of the pedal crank shaft, a sleeve mounted
thereon, an inner cone ball-bearing mounted upon each end of said sleeve, a
series of balls, outer-cone ball-bearings, and the frame of the bicycle having eyes
receiving said outer cones, said eyes carrying two parallel arms A2 and two forked
arms A and A3, substantially as described.
Dated this 12th day of Contember 1892
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.