Improvements in Brakes for Velocipedes.
Year: 1897

page_text: Date of Application, 12th Feb., 1897
Complete Specification Left, 21st Oct., 1897-Accepted, 1st Jan., 1898
PROVISIONAL SPECIFICATION
Improvements in Brakes for Velocipedes.
I, THOMAS ALFRED HEARSON, of Cooper's Hill, Englefield Green, Surrey,
Professor of Engineering, do hereby declare the nature of this invention to be
as follows:-
This invention relates to brakes suitable for a bicycle or other velocipede in
which the brake aay be applied by the process of back-pedalling and consists,
firstly, of a special form of brake, and secondly, of methods whereby the same
brake which, when the foot is on the pedals, can be brought into action by back-
pedalling may, when the foot is off the pedals, be applied by the hand or other
means.
According to the first portion of my invention I secure to the frame of the
velocipede a hollow cylinder concentric to the axis of the driving wheel of the
velocipede the motion of which is required to be arrested, and fix it adjacent to
the hub chain wheel whereby the velocipede is urged. The hollow cylinder is
provided with one or more feather-keys which project inwards, and a number of
washers having corresponding key-ways cut on their outer peripheries are placed
within the hollow cylinder. Alternating with these washers, which are thus pre-
vented from revolving, another set of washers is provided small enough in
diameter to be capable of revolving within the space inside the previously
mentioned feather-keys, and which have key-ways cut on their inner peripheries
to fit over one or more feather-keys which form a part of, or are secured to, the
wheel the motion of which is required to be arrested.
In one construction the lock-nut employed to prevent the unscrewing of the
small chain wheel on the back driving wheel of a safety bicycle is formed with
feather-keys on its outside surface and carries the second set of washers. If by
any means the two sets of washers are pressed together a frictional resistance to
their relative motion will arise between each pair of surfaces which will act as a
retarding force to the velocipede. The washers may be pressed together by a
force applied to the washer at one end of the double set or at the other end, and
according to my invention the force is a applied to one of the end washers by
causing the chain-wheel, by the process of back pedalling, to unscrew to a small
extent away from a collar or stop against which it presses when the velocipede
is being urged forward. The unscrewing will produce a small lateral movement
of the chain-wheel and cause the washers to be squeezed together, and thus the
brake may be applied. Secondly by means of a screw, screws, wedges or cams the
other extreme washer may be forced laterally by an effort transmitted from a
hand-lever or from a lever to which the foot may be applied, and in this way the
brake may be brought into action when the foot is off the pedals.
Dated thin lfth day of Wah1007

page_text: Improvements in Brakes for Velocipede:.
I, THOMAS ALFRED HEARSON of Cooper's Hill, Englefield Green, Surrey,
Professor of Engineering do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
1
This invention relates to brakes suitable for a bicycle or other velocipede, and
consists: Firstly, of a special form of brake, and secondly, of methods whereby
the brake can be brought into action, either by the process of back-pedalling or
by a force transmitted from a hand-lever. According to the first portion of my
invention, I secure to the frame of the velocipede a hollow cylinder, concentric
to the axis of the driving wheel of the velocipede the motion of which is required
to be arrested, and fix it adjacent to the hub-chain-wheel whereby the velocipede
is urged. The hollow cylinder is provided with one or more feather-keys which
project inwards, and a number of washers having corresponding key-ways cut on
their outer peripheries are placed within the hollow cylinder. Alternating with
these washers, which are thus prevented from revolving, another set of washers is
provided small enough in diameter to be capable of revolving within the space
inside the previously mentioned feather-keys, and which have key-ways cut on
their inner peripheries to fit over one or more feather-keys which form a part of
or are secured to, the wheel the motion of which is required to be arrested.
In one construction the lock-nut employed to prevent the unscrewing of the
small chain-wheel on the back driving-wheel of a safety-bicycle is formed with
feather-keys on its outside surface and carries the second set of washers.
If by any means the two sets of washers are pressed together, a frictional
resistance to their relative motion will arise between each pair of surfaces, which
will act as a retarding force to the velocipede. The washers may be pressed
together by a force applied to the washer at one end of the double set, or at the
other end; and, according to my invention, the force is applied to one of the end
washers by causing the chain-wheel, by the process of back-pedalling, to unscrew
to a small extent away from a collar or stop against which it presses when the
velocipede is being urged forwards. The unscrewing will produce a small lateral
movement of the chain-wheel and cause the washers to be squeezed together, and
thus the brake may be applied. Secondly by means of a screw, screws, wedges or
cams the other extreme washer may be forced laterally, by an effort transmitted
from a hand-lever, or from a lever to which the foot may be applied, and in this
way the brake may be brought into action.
Both methods of applying the same brake may be provided, or only either the
back-pedalling method, or the hand arrangement.
Figures to 13 Sheet 1, show the details of the construction of the brake as
designed for a rear-driven safety-bicycle and the means for applying the brake by
back-pedalling.
In Figs 1 and 2 of the same sheet a construction is shown whereby the same
brake may be applied also by a force transmitted from a hand-lever. This portion
of the construction may be omitted, in which case the brake will be capable of
being applied only by back pressure on the pedals.
Figs 14 to 23 Sheet 2, show the modification of the construction which I propose
to adopt when it is intended that the brake should be applied only by hand.
Referring to Sheet 1, Fig. 1. is a sectional-back-elevation in which the upper
half is taken on the vertical radial plane indicated by V in Fig. 2, and the lower
half is taken on a radial plane indicated by W.
Fig. 2 is a side elevation, the upper half being a section taken on the transverse

page_text: plane indicated by T in Fig. 1.
The arrow shows the direction of rotation for
forward motion of the bicycle. Figs. 3 to 13, are various views of details of the
construction.
The hub H to which the brake is fitted is of an ordinary construction and is
provided with ball-bearings not shown in the figures, this portion not being drawn
in section. A me-pitched right-handed screw-thread R H is provided just as
would be required to receive an ordinary small chain-wheel and there is also a
fine-pitched left-handed screw-thread LH such as is ordinarily provided to receive
a lock-nut.
In this invention the outer surface of what does duty for the lock-nut LN,
Figs 3 and 1, is provided with four projections over which are fitted a number of
thin washers RW shown in Figs 4 and 1. These washers can move endways and
are compelled to rotate with the wheel of the bicycle. Any resistance which may
be offered to their rotation will both tend to tighten the lock-nut LN, and retard
the bicycle. FD. in Figs. 1, 2, and 6, is a fixed drum which is mounted con-
centrically with the axle, and, by means of the two flats F, and F, which fit in
the recess of the fork such as is ordinarily provided in the frame of a bicycle, this
drum is prevented from turning. The inner surface of this fixed drum is provided
with four inward projections, and a number of washers FW, Figs 5 and 1, are
provided, with recesses on their outer peripheries, which fit within FD. These
washers are thus capable of end motion but are prevented from revolving.
2
The fixed washers FW, and the revolving washers RW, are inserted into the
drum FD alternately with one another, and then the drum being threaded on the
axle, the R W washers will slide on to the lock-nut L N.
If by any means the several washers are squeezed together a considerable
frictional resistance will be offered to the rotation of the revolving washers RW
which will retard the bicycle.
To remove the danger of the metal surfaces of the washers seizing one another,
I interpose between each revolving washer RW, and fixed washer EW, a washer
cut out of very thinly rolled sheet copper or bronze which can either turn with the
RW washer, or remain at rest with the FW washer, or take an intermediate
speed.
There are two possible ways of putting on the squeeze, viz. one by thrusting the
left end washer to the right by back-pedalling; the other by thrusting the right
end washer to the left.
The back-pedalling process of putting on the squeeze is provided for as follows.
On to the fine-pitched right-handed screw-thread previously mentioned is screwed
a bush B, shown in Figs 10, 11 and 1, on the outer surface of which is formed a
quick-pitched double-threaded screw-thread, and on this the small chain
wheel CW, Figs 7, 8 and 9, is mounted. The bush B is constructed to receive and
hold fast two pieces S, one of which is shown in Figs 12, 13, 1 and 2. These
pieces $ firstly, provide stops or shoulders against which surfaces S, and S.,
Figs 7 and 8, formed on the chain wheel CW butt, when the bicycle is being
urged forward. The pieces S, secondly, are provided each with a spring-tail, the
end of which by dropping into one of several recesses formed on the chain-wheel
piece CW, Figs 7, 8 and 2, will be retained in that position until by the applica-
tion of a moderate pressure on the pedals, either forwards or backwards, the
position is changed. The chain-wheel C W has two gaps in its hub permitting it
to turn relatively to the bush B, and bicycle-wheel, from the position in which the
surfaces S, and S. butt against the stops S, backwards through nearly a right
angle. The first mentioned position is that occupied when the bicycle is being
urged forward. By back-pedalling the chain-wheel CW is turned backwards
relatively to the stops S, and the lateral motion derived from the quick-threaded
screw-thread puts a squeeze on the washers and the brake is thereby applied. By
the tail end of the springs S fitting the recess into which they have dropped, the
brake will be continued in action, without continued back-pressure on the pedals,
until a forward pressure is exerted sufficient to displace the springs from the

page_text: recesses,
and take off the squeeze. When pedalling forward the tail of S fit into
recesses and prevent an inadvertent application of the brake, unless the back-
pressure exceeds a determined amount.
To assist in holding the pieces S in place, and to protect the spring tails from
the dirt, a cover-plate CP, Figs 1 and 2, is provided, and the pieces S are secured
to it by screws. The squeeze may be put on, and the brake applied, also by
thrusting the right end washer to the left by means of two screws, only one of
which is shown in Figs 1 and 2. Small cranks on these screws are joined by a
link so that the two screws may be moved by equal amounts by a force trans-
mitted from a conveniently placed hand or foot lever. Also by means of these
screws the brake may be adjusted after wear.
On Sheet 2 are shown, Figs. 14 to 23, giving the details of the construction of
the brake I propose to adopt when it is intended that the brake should be applied
only by hand. In this case the brake may be fitted to the front steering wheel if
the hub and frame fork leave sufficient room, but the drawings on Sheet 2 show a
construction and proportion suitable for the hub of a rear wheel as ordinarily con-
structed. The side of the hub way from the chain wheel is in this case adopted
on account of the space which is available without any alteration in the
proportions of the bicycle.
Fig. 14. is a side elevation, the upper half being a section taken through a
transverse plane indicated by T in Fig. 15. The arrow shows the direction of
rotation for forward motion of the bicycle.
Fig. 15. is a back elevation, the upper half being a section taken on a vertical
plane through the axis of the wheel.
Figs. 16 to 23 show the details of the construction. The hub of the wheel, at
the part containing the ball-bearing, is provided with a right-handed screw-thread
on to which is screwed a piece L N formed just like the piece L N Fig 3. Sheet 1,
and a set of washers RW, formed like those previously described and shown in
Fig. 4, are threaded on to L N. The second set of washers FW, made like those
shown in Fig. 5, fit inside of a drum D, Figs. 18, 19, 14 and 15, which is
capable of end motion, but is prevented from turning by means to be afterwards
described. The drum D) is inserted within the fixed drum FD, Figs 16, 17 14
and 15. FD is held at rest concentrically to the axle just as described in the previous
construction Sheet 1. The drum D, Figs. 18 and 19, has on its outer surface two
quarters of each of two outwardly projecting rings so situated that, as viewed in
Fig. 18, the four quarters together appear to make nearly a complete ring, but as
seen in Fig. 19, which is partly in section and partly in plan, the two quarters of
the one ring are not in the same plane with the two quarters of the other.
The fixed drum FD) has two quarters of an inwardly projecting ring. If now
the drum D is applied with its open end to the open end of the fixed drum FD),
it may in one position be inserted within it a sufficient distance to allow it to be
rotated through a right angle, and, after this, it may be pushed further in, so that
the two quarters of the outer ring of D will with the two quarters of the inwardly
projecting ring of FD form a complete ring, and the butting of the edges of the
quarters will provide the means which will prevent D from turning. When 1)
is thus inserted within FD) the internal quarters of the ring of D will stand
opposite to the quarters of the ring of FD. By increasing the distance of these
opposite quarters from one another a squeeze will be put on the washers and by
diminishing the distance the squeeze will be relaxed and thus the brake may be
applied and released. To produce the required lateral movement of D relatively
to FD) a pair of hardened steel cam-pins P, and P₂ of elliptical section,
Figs. 20 14 and 15, are interposed between the opposite quarters of the before
mentioned rings. By turning the cam-pins through a right angle the extent of
the movement of I will be equal to the difference between the major and the
minor axes of the ellipse.
2
2
The two cam-pins P, and P, are caused to be turned through equal angles by
means of levers and a link L as shown in Figs. 20, 21, 14 and 15. To apply the

page_text: brake a pull is exerted on the link L by transmission from the hand-lever on the
handle-bar of the bicycle, and the brake is released by the backward pull of a
spring not shown in the drawings.
In order that the washers may be separated when the cam-pins regain their
normal position two springs made of steel wire, as shown in Figs. 22 and 23, and
tempered, are inserted in the two vacant spaces between D and FD. They are
first placed behind the quarters of F D and when D) is inserted and turned through
a right angle relatively to FD) the springs will be carried with it through a
quarter of a turn. Before inserting D within FD) the washers are fitted into D,
alternately an FW and an R W washer with an interposed washer of thin copper
or bronze.
In Figs 18, 19 and 15 a method is shown whereby the brake may be adjusted
after wear, by setting up the surfaces of the washers nearer one another.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1. The employment of an alternate series of revolving washers and fixed washers
which are capable of being squeezed together for the purpose of retarding the
motion of a velocipede.
2. A construction whereby an alternate series of revolving washers and fixed
washers may be squeezed together for the purpose of retarding the motion of a
bicycle by the lateral movement of a chain-wheel derived by causing it to be
partially unscrewed by back-pedalling.
3. A construction whereby an alternate series of revolving washers and fixed
washers may be squeezed together for the purpose of retarding the motion of a
bicycle by thrusting the washer at one end of the series towards the others by
means of screws or cams actuated either by the hand or by the foot.
4. The combination of both methods of putting on the squeeze described in
Claims 2 and 3.
5. Brakes for bicycles constructed substantially as described and shown in
Figs 1-13 Sheet 1.
6. Brakes for bicycles constructed substantially as described and shown in
Figs 14-23 Sheet 2.