Improvements relating to Cycles.
Year: 1897

page_text: Date of Application, 16th June, 1897-Accepted, 7th Aug.,
1897
Improvements relating to Cycles.
I, LUCIEN STEPHEN CRANDALL, of 62 Moor Street, in the City of Birmingham,
Engineer, 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:-
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This Invention consists of improvements relating to cycles, my objects being_to
provide means whereby the rider on back pedalling can readily change the ratio
of the driving gear, and also to construct and arrange more simple and effective
brake mechanism operative by the act of back pedalling.
In order that my invention may be the more readily understood I append here
unto, two sheets of explanatory drawings, to be hereinafter referred to.
Figure 1, on sheet 1, is a diagram of a portion of a cycle illustrating the appli-
cation thereto of my combined gear changing and brake mechanism.
Figure 2 on sheet 2 is an end elevation and Figure 3 a sectional side elevation
on the line a b Figure 2 representing the combined gear changing and brake
mechanism, to a larger scale.
Figure 4 is a side elevation and Figure 5 a plan representing the brake mechan-
ism as used independently of the gear changing mechanism.
Figure 6 is an elevation representing the arrangement of the rear or driven
chain wheel of a chain geared cycle to adapt it for use with my improved brake
mechanism.
The same reference letters in the different views indicate the same parts
In the construction and arrangement of my combined gear changing and brake
mechanism as illustrated in the drawings, I braze or otherwise secure to the
bottom bracket A and the stay tubes B the girder or bridge bracket C. On the
upper side of such bracket C I form bearings or supports for the sliding brake
rod D having the brake block D¹ at its end adjacent to the rear wheel E. The
opposite end of the rod D is fitted with a pawl F which is retained by the action of
any suitable spring in contact with the cam collar or boss G formed upon the crank
axle H of the cycle. When the single cam or ratchet like projection of the cam
collar or boss G is in the position indicated in full lines at Figure 3, one of the
pedals will be in position for effective back pedalling, and if the rider then applies
a sufficient back force on such pedal the crank axle will be caused to turn slightly
in the reverse direction, or in the direction opposite to that indicated by the arrow,
and by the abutment of the projection against the pawl F the sliding rod D will
be moved against the action of the spring J, and thus the block D¹ will be forced
against the wheel E to brake or arrest its motion. When the axle runs in the for-
ward direction indicated by the arrow the projection 9 will slip under the nose of
the pawl F and no movement will be imparted to the rod D.
The mechanism for effecting a change in the ratio between the driving and
driven parts of the propelling mechanism, is especially applicable to the form of
gearing described in my Specification No. 10578 of 1897, which comprises an
eccentric mounted upon or secured to the crank shaft and arranged to oscillate a
variable lever in attachment with a pitman or rod connecting with the rear wheel.

page_text: Such mechanism is carried on the lower or under side of the bracket C, and it com-
prises the pawl lever K engaging with the ratchet wheel or ring L, the crank
plate M, and the rod N connecting with the arm by which the position of the
variable lever P connected with the pitman or rod is adjusted. The arm 0,
lever P, and rod Q form part of the hereinbefore named driving gear.
The ratchet wheel or ring Land the crank plate M are preferably formed to-
gether and in one piece with the central' and hollow trunnion or shaft on which
they are carried in the seating formed by the lower projection C from the brac-
ket C, and the cap C². The cap C2 is so arranged that it can be tightened on the
trunnion by the screws or studs c, and by such means I am enabled to set up suffi-
cient friction to prevent any movement of the ratchet wheel L and crank plate M
under the jolting or jarring of the machine when in motion.
When the projection g of the boss or collar G is in the position indicated by the
dotted lines at Figure 3, the pedal opposite to that by which the brake is actuated
as hereinbefore described, will be in position for back peaning, and if the rider
iuri slightly in the reverse direction, or in the direction opposite to that indicated
then applies a sufficient back force on such pedal the crank axle will be caused to
by the arrow, and by the engagement of the projection g with one end of the pawl
lever and the engagement of the opposite end of such lever with the ratchet
wheel L, the latter will be rotated a distance equal to one or more teeth and as
such motion is imparted to the lever P an adjustment in the ratio between the
driving and driven parts of the propelling mechanism will be effected. After the
wheel L has been advanced a distance of one or more teeth as described the pawl
lever K will automatically disengage itself, but under the action of any suitable
spring it will drop into the next tooth, and thus when the pedal is again in posi-
tion for back pedalling a further adjustment of the gearing can be effected.
By my combined brake and gear changing mechanism a rider by. the act of
back pedalling with one foot or on one side of the machine can readily apply a
simple and effective brake whilst on back pedalling with the other foot he is
enabled to change the ratio of the driving gear whilst the machine is in motion.
I sometimes employ my gear changing mechanism and brake mechanism inde-
pendently. Figures 4 and 5 are detail views of the brake mechanism when
employed independently, whilst Figure 6 illustrates an arrangement of ordinary
chain gearing suitable for use in combination with such mechanism, the rear
chain wheel being mounted upon rollers which lock or engage when the chain
runs in the forward direction, but which disengage when a back pedalling force
is applied to the chain, thus permitting of sufficient back movement of the crank
axle to enable the brake mechanism to be operated as hereinbefore described..
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is-
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1. In cycles, the use of a back pedalling force for the purpose of effecting a
change in the ratio of the driving gear substantially as described.
2. The combination of cycle pedals with means whereby by the application
of a back force to one pedal effects a change in the ratio of the driving gear and
the application of a similar force to the opposite pedal applies the wheel brake,
substantially as described.
3. The improved cycle brake operative by the act of back pedalling, compris-
ing a sliding rod and block having a ratchet like connection with the crank axle,
and means whereby the driving gear will disengage on the application of a back
pedalling force, substantially as described and as illustrated.
4. In cycles, the combination comprising a ratchet or pawl lever in connection
at one end with a ratchet like projection from the crank axle, and at the other end
with a ratchet wheel formed with or rigidly attached to a crank plate which is
connected with the driving or propelling mechanism, substantially as and for the
purposes described and as illustrated.

page_text: 5. The improved combination and arrangement of cycle gear changing and brake
mechanism substantially as described and as illustrated.
Dated this 14th day of June 1897.
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicant.