Improvements in Bicycles.
Year: 1898

page_text: Date of Application, 4th Feb., 1898-Accepted, 14th May, 1898
COMPLETE SPECIFICATION.
Improvements in Bicycles.
I, HENRY BIRKBECK, of the Firm of Tongue & Birkbeck, of 31, Southampton
Buildings, Chancery Lane, London, England, Fellow of the Chartered Institute
of Patent Agents, do hereby declare the nature of this invention (a communication
to me from abroad by Marion Lafayette Nichols, of 51, D Street, Southeast, in the
City of Washington, District of Columbia, United States of America, Inventor)
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
My invention relates to improvements in bicycles of the type commonly known
as the chainless safety, and it has for its object to improve the construction of the
bicycle throughout, and especially to provide an improved brake, improved means
for adjusting the handle bars, improved apparatus for operating the bell, improved
driving gear, and an improved lock. With these objects in view, my invention
consists in the constructions and combinations of parts as hereinafter described
and particularly set forth in the claims.
In the accompanying drawings,
Figure 1 is a side elevation shewing my improvements as applied to a lady's
tandem.
Figure 2 is a side elevation of a triplet.
Figure 3 is a side elevation of a man's single machine.
Figure 4 is a longitudinal central section through the handle bar head and
adjacent parts.
Figure 5 is a cross-section on the line 5-5 of Figure 4.
Figure 6 is a cross-section on the line 6-6 of Figure 4.
Figure 7 is a fragmentary view, partly in section, shewing the arm for operating
the brake.
Figure 8 is a side view of the bracket supporting the rear or driving wheel.
Figure 9 is a side view of the same, the bracket being shewn inverted and the
cover removed.
Figure 10 is a longitudinal section through the handle bar head shewing a
modified construction of the means for locating the handle bar in any one of several
possible positions.
Figure 11 is a horizontal, sectional view taken through the centre bracket, but
shewing part of the brake in full lines.
Figure 12 is a vertical section taken on the line 12-12 of Figure 11.
Figure 13 is a fragmentary view, partly in section, shewing a modified form of
the hand lever which operates the brake.
Figure 14 is a section upon the line 14-14 of Figure 15.
Figure 15 is a section on the line 15-15 of Figure 14.
Figure 16 is a view taken on the same plane as Figure 14, but shewing a modified
form of lock, and brake.
Figure 17 is a horizontal section shewing the means for driving the rear wheel.
Figure 18 is a horizontal section through the driving gear of the triplet, parts
being broken away.

page_text: Figure 1 is a detail view, partly in section, of the handle and connected parts
used in changing the gear.
Figure 20 is a plan view of the same.
Figure 21 is a horizontal, sectional view taken through the driving gear of a
candem, parts being broken away.
Figure 22 is a side view of the rear bracket of a tandem machine with the plate
removed.
Figure 23 is a side view of the same taken from the opposite side, the bracket
being inverted, and the side plate being removed.
Figure 24 is a side view on a smaller scale of a part of the same bracket, shewing
the connecting hinge.
Figure 25 illustrates a third form of lock.
Figures 26, 27, 29, 30 and 31 shew modifications of the brake.
Figure 28 is a cross-section through the steering fork, shewing the means for
preventing the front wheel from swinging more than half a revolution.
Figure 32 is a detail view of the centre bracket lock.
Figure 3 represents a side view of the centre bracket for a single machine,
shewing in dotted lines the hinged portion swung down.
Figure 34 is a top view of the same, parts being broken away, and shewing the
internal gearing.
Figure 35 is a side view of the same with the hinged portion removed and
provided with an additional socket, the whole being adapted for use in a tandem.
Figure 36 shews a modified form of the gearing for driving the rear shaft of a
tandem; it also shews a changeable gear, and means for shifting said gear.
Figure 37 is an end view of the shifting mechanism; and
Figure 38 is a side elevation of the same.
Referring especially to Figure 3, A represents the frame of the machine, B the
centre bracket, C the handle bar, and H the rear bracket. This frame is of the
diamond type, but obviously a drop frame might be used, as shewn in the front
half of Figure 1. The handle bar is mounted in a steering fork in the usual way,
except that by means of the device E, shewn in detail in Figure 28, the front
wheel is allowed to swing only one-half a revolution. The handle bar is adjustably
secured in the handle bar head, and held in various positions in the manner shewn
in Figures 4 and 10, in which C₁ represents the handle bar head with the handle
bar passing through it. The handle bar C is provided with slots C2. A pin C³
passes through the handle bar and through notches C16 (usually six in number,
as shewn in Figure 6, arranged in two symmetrical groups of three each) in one
end of the handle bar head.
Caps C and C³ are located at each end of the handle bar head, the cap C+ being
secured to the handle bar and handle bar head in such a way as to prevent the
handle bar sliding in the head, while allowing it to rotate a limited amount. The
amount of rotation is determined by the length of the slot C, (see Figure 5) in
which the screw C7 is free to play.
Referring now to Figure 4, the pin C3 has attached to it a link which in turn
is attached to the bell crank lever C8 which is supported by the pin C9 passing
through the handle bar and riveted thereto. The bell crank lever C8 is free to
move in a slot in the handle bar, and is usually in the position shewn in solid
lines in Figure 4. When it is desired to adjust the handle bar, the lever C8 is
thrown down into the position shewn in dotted lines, which draws the pin C³,
carrying with it the sliding collar C, out of the notches in the handle bar head.
The handle bar is then turned as desired until the pin C3 is opposite one of the
notches in the handle bar head, when the lever C8 is thrown back into its normal
position, and the adjustment is complete.
A modification of the means for operating the pin C is shewn in Figure 10,
in which a link Co is pivoted to the pin C³, and another link C is pivoted on a
pin riveted in the handle bar, and is also pivoted to the link C10 in such a way
that the two links form a toggle joint. A sliding pin C12 provided with a button Ci³

page_text: passes through the handle bar, and is connected with the pivot point of the two
links. By pressing the lower end of the pin C upward, the pin C3 and the sliding
collar C are drawn away from the handle bar head; otherwise, the operation is
as has been before described.
The handle bar head is provided with a screw-threaded extension C8 which in
turn is extended further and reduced in size, as at C, where it engages with an
enlarged portion C2 of the stem of the steering fork. A nut C provided with
an internal groove C10 engages with the part C8. A pin C engages the groove C
and passes through the stem. The extension C8 is provided with a slot C¹ in
which the pin C¹³ plays. By screwing up the nut C the handle bar head and stem
are firmly bound together.
The upper part of the steering fork is hollow, and the handle bar and handle
bar head are also hollow, and are provided with openings for the passage of a brake
cord F. This cord is attached to a brake which engages the crank shaft in the
centre bracket. This cord F is pivoted at its upper end to a swinging arm Fl
(see Figures 7 and 13) pivoted in the handle bar C at the upper part thereof, the
lower part extending through a slot in said handle bar, and provided with a
ring F
The brake cord or chain F and the bell cord C** may, if desired, be attached
directly to rings F* as shewn in Figure 3, omitting the pivoted arm.
Figures 7 and 13 are practically the same except in the manner in which the
arm F is pivoted.
The brake itself F³ is a strap, preferably of steel, supported upon a pin F4, screwed
into the rear part of the centre bracket and wound spirally upon the drum F5.
This drum is formed as follows:-The crank shaft G has an enlargement g Fig. 11
made integrally therewith and provided with a shoulder g² against which the gear
wheel G¹ is adapted to rest. The remainder of this enlargement is provided with
a screwthread, and the drum F5 is provided with an internal screwthread, so that
this drum has the double function of securing the gear wheel G¹ in place and of
providing a surface for engagement with the brake.
The other end of the strap, after passing two or three times around the drum,
is attached to a lever F6 by means of a loop, and to the other end of this lever the
cord or chain F is attached. It follows, therefore, that if the arm F is pulled
back, the cord F acting upon the lever F6 will tighten the strap upon the drum
and act as an effectual and easily operated brake.
A modified form of brake is shewn in Figures 14 and 15.
In this case, the cord F is pivotally attached to a lever F7 which is arranged
nearly at right-angles to the crank shaft. The brake itself consists of a wide
strap F8 passing around the drum F5 upon the crank shaft, and having its ends
attached at different points to the lever F7. The loop of the strap passes over a
pin F supported in arms F10 in the casting F". A coil spring F1 is centrally
mounted on the pin F and serves to hold the strap away from the crank shaft
until it is desired to apply the brake.
In Figures 26, 27, 29, 30 and 31 are shewn other modifications of the brake.
In Figure 26 an arm F21 provided with a curved face, is pivoted upon the pin Faz
To this arm is attached the brake cord. The coiled spring F23 bears against the
arm Fa, normally holding it out of contact with the drum F5.
In Figure 27 the cord is attached to an arm F2 pivoted on a pin F. The
arm F2 engages another swinging arm F25 provided with a curved face and
pivoted on the pin F26. The coiled spring F23 has already been described.
In Figure 29 the brake cord is attached to the swinging arm F28 pivoted on the
pin and provided with a curved face for engaging the drum on the crank shaft.
The face of the swinging arm is held with a yielding pressure, when the cord is
pulled against the drum F. This pressure is produced by the spring F" in the
arm F, the curved face being provided with an extension F29 sliding in an opening
in the arm F27. By means of nuts this-spring can be adjusted to any required
degree of tension,

page_text: In Figure 30 is shewn another form of brake constructed something on the
principle of ice tongs. In this case the brake consists of two jaws F30 nearly
encircling the drum F. These jaws are pivoted to links F31, which in turn are
pivoted to links 132, the whole forming a quadrilateral and the links F32 being
mounted on the pin F22. The brake cord is pivoted to a bent lever F33, which in
turn is pivoted to the link F4 and is also pivoted to one of the junctions of links F31
and F32 A pull on the cord obviously causes the jaws to grip the drum. A coil
spring F engages the links F32, serving to throw them apart and thereby dis-
engage the jaws from the drum when the cord is not pulled.
In Figure 31 the arrangements of the cord, links and spring is the same, the
only difference being that the curved face of the brake is driven directly against
the drum by the movement of the arms F31.
The bell is mounted in the usual way upon the handle bar, and is operated by
means of a cord passing through a slot in the handle bar and connected to one of
the arms F¹.
My invention also relates to means for locking the bicycle, means for which
are shewn in Figures 14, 16 and 25. In Figure 14 the casting F is provided
with a second pair of arms F12 in which is a sliding bolt F13, which is adapted to
slide into and out of notches in the main gear wheel in the centre bracket.
lock F14, of any desired construction, is let into the centre bracket, and the bolt F13
is operated by the turning of the key in said lock.
A
In Figure 16 is shewn a construction similar to that shewn in Figure 14, except
that the casting F has only one pair of arms, and the pin F15 serves not only as
a supporting pin for the brake strap, but also serves as the bolt which is operated
by the key in the lock.
In Figure 25 is shewn another form of lock which upon the whole is deemed
preferable. In this lock the bolt F17 is supported by two arms F16 of the casting Fu.
To this casting is pivoted a bell crank lever F18, the lower member of which is
pivoted to the bolt F", and the upper member is pivoted to the lock F. The
coiled spring F20 is arranged between the casing and the upper member of the
bell crank lever to prevent the bolt F17 from being moved by the jar of the machine.
When it is desired to lock the machine, the lock F¹ is pushed down until it is
flush or slightly below the outer surface of the bracket. When it is in this
position it is almost impossible to withdraw it except by the aid of a key.
Figure 28 shews a screw E passing through slots cut in the handle bar head and
stem, which slots usually extend about half way around.
The crank shaft is supported in a centre bracket B. This bracket is cast solid
except for the lower part B¹, which is hinged thereto, and is provided with two
rearwardly projecting, hollow bearings B2 in which are mounted the tubes B³
connecting the centre bracket by means of intermediate connections to the rear
wheel, and is provided with a hollow bearing B4 arranged near the centre of the
tube, and projecting slightly backwards, and with another hollow bearing B
arranged centrally near its front, which bearings receive two of the tubes of the
frame work. Bearings for the crank shaft are located about centrally of said
bracket.
The rear of the bracket B is provided with projections to which are pivoted
projections on the swinging portions B'. This part B₁ is arranged to be swung
up into position and secured by the spring lock 6 shewn in Figure 31 and in detail
in Figure 32. If desired, it may be so arranged that the same key may be used
for the lock b and for the lock which is used to engage with the main gear wheel
in the centre bracket.
The crank shaft G is supported on ball bearings of the usual type, screwed into
the bearings of the bracket B. This crank shaft is provided with a gear wheel G¹,
preferably of the form shewn in Figure 14. The body of the gear wheel is flat
but provided with teeth set at an angle of about 45° to the face of the gear wheel,
which is perforated at intervals to allow the passage of a bolt through one of said
perforations. This gear wheel is firmly fastened by the drum F5 on the crank

page_text: shaft & as herein before described which drum at the same time provides a surface
for engagement of the brake mechanism. This gear wheel meshes with a beveled
gear wheel G mounted in ball bearings located in the rear part of said bracket,
said gear wheel being mounted upon a shaft G³. The rear end of this shaft has
a beveled gear wheel G mounted in bearings in the rear bracket H.
This bracket is shewn in detail in Figures 8 and 9. The inner side, next the
wheel, is flat, as shewn at H¹, for the reception of a sheet metal cover H². The
front part of the bracket is elongated into a sort of a neck H³, into which is screwed
a bearing for the rear end of the shaft G³. Immediately behind this neck is an
enlarged chamber H in which the gear wheel G revolves. In the rear of the
space is a partition H³ provided on its rear with a thickened portion Ho, which
when bored out and with a sleeve inserted therein, forms a bearing for the shaft H7,
(see Figure 17) to one end of which is rigidly secured a two-faced gear wheel H8
one face of which is beveled and meshes with the gear wheel G. The other face
meshes with the gear wheel H secured to the hub of the rear or driving wheel. In
the rear part of the bracket is the solid portion H10 which, when bored out, serves
as a bearing for the axle H" of the rear wheel. A solid projecting portion H¹³
is located nearly above the portion H10, and serves for the reception of one of the
frame tubes. This projecting portion may be made hollow, if desired, or it may be
omitted altogether and the frame tube screwed directly into a hole in the rear
bracket. This rear bracket is cast in one piece, and of itself forms bearings for
the transmitting shaft G³, the connecting shaft H7, and the axle of the rear driving
wheel, thus affording decided advantages over the built up brackets now in common
use. I prefer to make this bracket, as well as the centre bracket, of aluminum,
but do not limit myself to this material. It is obvious, without further explanation,
that the movement of the crank shaft will through the medium of the gear
wheels G1, G2, G, H and H, cause the rear wheel to rotate about the axle H",
upon which it is mounted on ball bearings in the usual manner.
On the other side of the hub of the rear wheel and on the axle H is mounted
a part H4 with which one of the tubes B3 engages. In the enlargement H⁰ and
between it and the axle H is mounted an eccentric washer h. By turning this
washer, the gear wheel H³ may be adjusted towards or away from the gear
wheel H8.
In Figure 1, I have illustrated a tandem, and in Figure 21, I have shewn the
gearing for driving the same. In this case, the rear seat is mounted on a frame
work A & A the latter detachably supported directly by the rear brackets K³
see Figs. 1 and 21 while the bar A is detachably connected at A*** (by a clamping
screw) to the main frame A and thus the frame A* A* with the saddle thereon
and handle-bars C* can be readily removed to make a single bicycle by detaching
same at the points K and A*** and removing the rear cranks.
In the tandem the centre bracket is of the usual type but the rear bracket K
is modified as shown in Figs. 21–24.
The front part of the bracket K is shaped like that on the single machine and
the tube B³ shafts G³ and H7 and bearings therefor and gear wheels G' H³ and H⁹
and the cover H2 are as have already been described. In this case however the axle
of the rear wheel is rotatable and is provided with cranks. The rotatable shaft
is mounted in ball bearings on each side of the machine, said ball bearings on
one side of the machine being located in a sleeve in the circular slot K' in the
bracket K.
One end of the shaft H" has fastened to it the gear wheel H12 which meshes
with the gear wheel H13 on the shaft H. A flat cover K2 preferably of sheet metal
is used to enclose this gear wheel in connection with the bracket.
The rotation of the main crank shaft G through the medium of the gear
wheels G G and G drives the gear wheel H which in turn drives the gear
wheel H mounted on the hub of the rear or driving wheel which rotates on ball
bearings on the shaft H". This shaft is also driven by the rear rider who by
means of the gear wheels H2 and H13 also helps to rotate the shaft H.

page_text: In Fig. 36 is shown a modification of the driving gear used on the rear shart
of a tandem or triplet.
In this case the rear axle H instead of being provided with a spur gear wheel
as in Figure 21 meshing with another spur gear wheel on the shaft H is provided
with a bevelled gear wheel H* which meshes directly with the bevelled gear
wheel G¹.
In Figure 36 is shown also the means for shifting the gear and in Figs. 37
and 38 detailed means for this purpose are shown.
This bevel wheel G+ also meshes with the bevel gear T¹ of a compound spur and
bevel wheel TT2 and T3 all fixed rigidly together but free to revolve on the inter-
mediate shaft H-the spur wheel 12 meshing with the spur wheel T indepen-
dently mounted (loosely) on the hub of the rear wheel.
The spur wheel T3 meshes with the spur wheel T5 also independently mounted
(loosely) on the hub of the rear wheel.
V is a grooved collar fixed to the hub of the rear wheel but movable laterally
with respect thereto but always revolves with the hub.
This collar V carries two (or other number of) laterally extending locking arms
or keys U which have enlargements U and U2 respectively at either end thereof
and smaller part U thereinbetween.
This collar V is adapted to slide laterally on the hub of the rear wheel and such
movement is controlled by the forked device W which latter is oscillated or
operated by any suitable connection such as the rod or shaft W1 journalled in the
aforesaid bracket K see Figs. 36 to 38.
These arms U fit in grooves formed in the hub and act by the engagement of
either of the ends U¹ or U2 with either of the gears 14 or T5 (but not both) to hold
it engaged with the hub of the rear wheel while permitting the gear wheel T or T5
not engaged to run loosely; or by bringing the cut-away portion U* directly in
line with the two wheels T and T permit the latter both to run freely without
communicating motion to the hub or in other words throwing the gear entirely out
of action.
The shifting fork W is pivotally mounted in the bracket K with its ends
engaging the groove of the shifting collar V. This fork W is rigidly connected
to the pivotal shaft W₁. Suitable means for holding the shifting fork W in any
particular position is shown in Figs. 19 and 20 as hereinafter described.
The rear part K³ of the bracket K is fastened thereto by bolts or a hinge K
may be used at the top if desired instead of the bolts. (See Figure 24.)
This part is also provided with a perforated projection K5 for the attachment of
the rear part of the frame.
The tandem may readily be converted into a single machine when desired as
hereinbefore described.
In Figure 2 there is shewn a triplet, and in Figure 18 a broken section shewing
the driving gears for the same, which is moreover provided with means for
changing the gear. In this case, the front bracket L which is provided with a
brake already described, is nearly cylindrical in horizontal cross-section, being
provided with three projections for the reception of three parts of the frame, as
shewn clearly in Figure 2. A crank shaft in this bracket is provided with a
beveled gear wheel L' which meshes with the beveled gear wheel L2 on the shaft L³,
which connects with a gearing in the second bracket M.
To economize space
the brake strap instead of being wound as shewn in Figure 18, may be wound upon
an enlargement of the hub of the gear wheel L'. This would necessitate the
shaft L³ running not exactly parallel to the main frame of the machine, but at a
slight angle thereto. In the bracket M. is the beveled gear wheel M¹ carried by
the shaft L. This gear wheel meshes with one face of the beveled gear wheel M²
mounted on the crank shaft in this bracket. The other face of the gear wheel M³
meshes with the beveled gear wheel M³ mounted on the shaft M* which passes into
the rear bracket N, and has a gear wheel M5 thereon, said shaft being supported
in ball bearings in the rear bracket N. The rear bracket and gearing therein

page_text: are substantially the same as those shewn in Figure 21, and have already been
described in connection with a tandem, except that said rear bracket and hub of
the rear wheel are provided with a changeable gear and means for holding the
machine at a high gear or at a low gear or permitting it to run without any
gearing. These means are shewn in detail in Figures 19 and 20, in which Ŏ
represents a flat plate fixed to the frame just below the middle saddle. This plate
is in the shape of a sector of a circle provided with three depressions for the
reception of a spring operated catch, and provided also with projections 02 to
prevent the handle 03 from being swung too far. This handle 03 is hollow, and in
it is a rod O which is connected to the means such as the rod W₁ for shifting the
gear. A spring O is attached to the handle and to the rod 0. The handle is
provided with a projection 06 which is adapted to engage in the notches O¹.. By
pulling the handle outward against the tension of the spring 05, it may be swung
so that the projection 06 will engage with any one of the notches O³, as described,
in which position it will be retained by the spring 05.
The tandem and the triplet are provided with connections R, by which move-
ment of the rear handle bars may be connected to the steering fork. This is of
the usual type.
Means for adjustably securing the tubes B³ to the bracket B are shewn especially
in Figures 11 and 12. The rearward extensions 132 of the bracket B are screw-
threaded and reduced at their outer ends. Circular nuts Bu provided with holes B12
with which a wrench may engage, and having the outer part made smailer, are
arranged to fit over the reduced portions of the projections B2. When these nuts
are screwed home they hold the tube B3 firmly in the projection B2. Other
circular nuts 13 provided with holes B315 engage with screwthreaded portions of
the tubes B and serve as jam nuts.
Having thus particularly ascertained and described 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. The improved means for adjusting the handle-bar, as shewn in Figures 4, 5,
6 and 10.
2. The improved means for operating the bell, as shewn in Figures 3, 4, 7,
10 and 13.
3. The improved forms of brake, as shewn in Figures 4, 7, 10, 11, 12, 13, 14,
15, 16, 18, 21, 26, 27, 29, 30 and 31.
4. The improved lock for bicycles, as shewn in Figures 14, 16 and 25.
5. The improved means for preventing too great a swing of the front wheel, as
shewn in Figures 1 and 28.
6. The improved centre bracket, as shewn in Figures 11, 12, 14, 15, 16, 21, 26,
27, 31, 33, 34 and 35.
7. The improved rear bracket, as shewn in Figures 8, 9 and 17.
8. The improved rear bracket, as shewn in Figures 21, 22, 23 and 24.
9. The improved driving gear, as shewn in Figures 16 and 17.
10. The improved driving gear, as shewn in Figure 18.
11. The improved driving gear, as shewn in Figure 21.
12. The improved driving gear, as shewn in Figure 36.
13. The improved means for changing the gearing as shewn in Figures 18, 19,
20, 36, 37 and 38.
14. The improved construction of bicycles and combinations of parts thereof
as set forth in the description and illustrated in the drawings.
15. In a bicycle, the combination of a notched handle bar head, a slotted handle
bar passing through said head, a pin adapted to engage the notches in said handle
bar head, and means for causing the said pin to move into and out of engagement
with the notches of the handle bar head, substantially as described and shewn.
16. In a bicycle, the combination of a supporting bracket, a crank shaft passing
through said bracket, a gear wheel supported on said crank shaft, a sliding bolt

page_text: adapted to be brought into and out of engagement with said gear wheel, and means
for operating said bolt, substantially as described and shewn.
17. In a bicycle, the combination of a crank shaft provided with a drum, a
brake adapted to engage said drum, a cord attached to said brake and passing
up through the frame and means for operating said cord, substantially as described
and shewn.
1000
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.
TO fen Sawer