A Friction-wheel. Brake.for Bicycles, Tricycles, and other ... Carriages.
Year: 1895

page_text: Date of Application; "11th Nov☺; 1995
..Complete; Specification Left, 11th Aug., 1896 Accepted, 7th Nov., 1896
PROVISIONAL SPECIFICATION.
A Friction-wheel. Brake.for Bicycles, Tricycles, and other
... Carriages.
I, WILLIAM JOSEPH SMITH, Clerk in Holy Orders, of Mortomley,, near
Sheffield, do hereby declare the nature of this invention to be as follows:-
Whereas the tyres of wheels of 'cycles and other carriages; composed of india-rubbor
or substitute therefor, are easily torn by the action of the brake, thereon, I claim
that by this my invention; such tyres are greatly saved from such injury.
My invention, to effect this purpose, consists in the: intervention, between the
brake and the carriage wheel, of an additional smaller wheel or roller. This
smaller wheel or roller is so placed; that its outer edge or tyre can be made to
press upon the tyre of the carriage wheel, in such: manner that. the revolution
of the carriage wheel shall cause the smaller wheel or roller also to revolve.... A
brake is arranged so that it can be made. to retard or impede the revolution of
the smaller wheel, and thereby retard: or impede the revolution of the carriage
wheel.
The wear caused by the brake is thus taken by the smaller wheel or roller,
which latter can be easily and cheaply replaced. The carriage wheels are thus
saved.
+
My invention'does not include any manner, of application of brake, nor any form
of brake, but applies only to the intervention of a smaller wheel or roller between
the brake and the carriage wheel, with the view of obtaining the action and effects
described above.
•
I wish to mention here that I find it useful to have the axle of the smaller wheel
running in slotted bearings..
1
T
...A Friction-wheel Brake for Bloyoles, Tricycles, and other
Le Carriages.
I WILLIAM JOSEPH SMITH Catholic Priest, Mortomley, near Sheffield do
heroby declare the nature of this invention and in what mannor the same is to
30 be performed, to be particularly described and ascertained in, and, by the following
_' statement -
This invention has reference to and comprises a new brake for oycles, cautocars
and other carriages, and has particular reference to such carriages as have their
wheels fitted with pneumatio tyres.
36 This brake consists of a smali wheel, herein called a friction-wheel sotfixed
that it can be readily interposed between a revolving wheel of a cycle or other
carriage and a brake, in such manner that ‘wheu so interposed it shall always be
revolved by friction with the carriage wheel, whilst at the same time the
revolution so given to it may always be retarded by friction with the brake.
DI

page_text: This retardation of the revolution of the friction-wheel, causes a retardation of
the revolution of the carriage-wheel, and thus the speed of the carriage is
controlled.
For the success of such a brake it is necessary that the friction-wheel shall
always revolve, and therefore that the force tending to revolve it, (the friction-
wheel,) be at all times greater than the force which tends to impede.its.revolution;
ie that the friction (which is the resistance to slipping) of the friction-wheel with
the carriage wheel be always greater than its friction with the brake. In other
words it is necessary to effect that the friction-wheel shall not slip upon the tyre
of the carriage wheel, which causes its revolution, but that it shall always slip under
the brake, whatever be the pressure it suffers therefrom. If this be not effected
the end in view of designers of rotary brakes is not gained, which end is the prevention
of injury to the tyres of 'cycles and other carriages, arising from the rubbing
thereof with a stationary brake.
.
The constant revolution of the friction-wheel is but imperfectly secured hy
covering its surface with india-rubber; because 1° when the india-rubber is wet
its co-efficient of friction with the tyre of the wheel is much diminished, and it
therefore more readily elips thereon; and 2° a slight obstruction, e.g. grit from
the road, occurring between the brake and the friction wheel is sufficient to
entirely stop the revolution of the former.
This invention, therefore, includes a mechanical application, whereby the
constant revolution of the friction-wheel is secured by causing its friction with the
carriage-wheel to be always greater than its friction with the brake. This
mechanical application consists in the use of a spring or springs, by the reaction
of which, when the brake is applied, the pressure of the friction-wheel upon the
carriage-wheel is made to be always greater than the pressure it receives from
the brake but inasmuch as friction varies directly with the pressure holding
the surfaces in contact, the friction of the friction-wheel upon the carriage wheel
is made to be greater than its friction with the brake: therefore the revolving
force which acts upon the friction-wheel is always greater than the retarding
force upon it, and its revolution becomes constant under every application of the
brake.
In order that this invention may be clearly understood and illustrated, drawings
are filed herewith.
Fig. 1 represents the application of such a friction-wheel brake to a bicycle. :
Fig. 2 represents its application to a carriage wheel.
In Fig. 1, A. B. C. represents the friction-wheel, which may be made of wood,
hard felt or other suitable material. A ring of india-rubber is cemented round the
rim thereof. The wheel is made to revolve truly round a spindle shewa.. KLN
represent a pair of brackets of steel wire which are attached to the forks of the
bicycle by the clips M. In these brackets an eye is formed at a.
DE is a band
of thin sheet steel attached at one end to the said brackets by the pin a, around
which it is turned, and which pin passes through the eyes above mentioned as
shewn. The other end of the steel band is also turned round a pin at b, which pin
passes at its centre through the rod H, thus connecting it with the brake rod R.
F G represent springs of best steel wire tempered. Near their centre they are so
turned as to form a bearing for the spindle of the friction-wheel. Their ends are
carried as shewn by the pins a and b.
The action of the brake is as follows. The brake-plunger R being depressed,
the band D.E is brought down upon the friction-wheel A B C, which is thus
made to press upon the tyre of the bicycle with a pressure equal to that which it
receives from the band brake D E. At the same time, by the downward
motion of the rod H, the springs FG are brought into action, and their reaction
: meets a resistance in the spindle of the friction wheel, which friction-wheel
pressed upon the tyre of the bicycle wheel with a pressure which is always distinct
from and in addition to the pressure derived from the band-brake. If the, bicycle
wheel be now] made to revolve, the friction-wheel A B C will suffer from two
thus

page_text: opposing influences, viz. -1° the influence of the friction with the revolving
carriage wheel tending to make it revolve, and 2° the friction with the stationary
brake D E tending to impede such revolution. Now friction varies with the
pressure as has been said above. Inasmuch therefore as the pressure of the
friction-wheel upon the tyre is always greater than' the pressure it receives from
the brake, owing to the re-action of the springs F G as explained therefore the
friction is also greater in the same proportion, and hence the revolving influence
upon the friction-wheel is always greater than the retarding influence upon it.
The revolution of the friction-wheel is thus secured under every application of the
brake.
The friction-wheels used are not mere rollers or cylinders whose diameters are
small compared to their axee, but they are wheels whose diameters are not less
than their axes. A convenient size for the friction-wheel of a bicycle is two inches
in diameter, and one and a half inches in axis.
Fig. 2 represents a friction-wheel brake applied to a carriage wheel. In this
case two friction-wheels are used as shewn at e. These are attached to the
spring d, which is made of tempered steel. When the brake is applied, the brake-
shoe e is moved in the direction of the carriage-wheel. First the friction wheels
come into contact with the tyre, and are revolved thereby. The spring e being,
weak, no sensible brake power is so far oxercised. The spring yields before the
continual pressure of the brake-shoe, until it (the latter) presses upon the friction-
wheels, and thus retards their revolution, and by so doing retards also the
revolution of the carriage-wheel. The constant revolution of the friction-wheels
is here secured by the reaction of the spring d, which by the pressure of its
reaction causes the friction-wheels to be always pressed against the carriage
wheel with a pressure in excess of the pressure it receives from the brake-shoe.
The revolving force upon the wheels is thus always greater than the force
retarding their revolution, and thus their constant revolution is secured.
Having now particularly described and ascertained the nature of my inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The use as a friction-wheel of a cylinder whose diameter is not less than its
axis, interposed between a revolving carriage wheel and a brake in such manner
that pressure from the brake may retard the revolution of the friction-wheel, and
thereby also retard the revolution of the carriage wheel. I limit this my claim to
the use of such a friction wheel, to such use as shall be in connection with some
application of the principle enunciated in No. 2 below.
2. Any application of this principle vie. -the revolution of any friction-wheel
or roller interposed between a revolving wheel and a brake is better secured by
introducing springs (or a spring) in such manner that by their reaction they shall
cause a pressure between the carriage-wheel and the friction-wheel independant of
and in addition to that pressure between them which arises from the pressure of
the brake upon the friction-wheel. I claim as a novelty the use of springs for the
purpose above described.
Dated this Eighth day of August 1896. ·