Improvements for Increasing the Speed of Velocipedes by the Aid of a Crank with an Extending Lever or Levers.
Year: 1891

page_text: Date of Application, 10th June, 1891
Complete Specification Left, 1st Dec., 1891-Accepted, 2nd Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements for Increasing the Speed of Velocipedes by the Aid
of a Crank with an Extending Lever or Levers.
THOMAS HENRY BROOKS 24, Handforth Road, Brixton Engineer in the Parish
of Lambeth, London, FRANK GEORGE HAMPSON 21 Doris Street, Kennington
Engineer in the Parish of Lambeth, London do hereby declare the nature of this
invention to be as follows :-
Our invention is a crank, with an extending lever or levers actuated by an
adjustable ball eccentric or camm.
In Fig. 1 the crank A has a lever B, attached with an adjustable ball joint, to
the other end of lever, is attached the pedal pin and one end of a connecting rod C,
with an adjustable ball joint, and knuckle joint arrangement, the other end of
connecting rod is attached to an eccentric strap D which by the action of pedaling
is caused to revolved round a fixed eccentric E, which is fixed to the frame of the
cycle and in some cases is intended to form part of the frame, the adjustable ball
bearings F for the pedal crank spindle are also contained within the eccentric.
Fig. 1 shews the pedal lever extended from the crank spindle, the dotted lines
shewing it returned,
Fig. 2 is the section of Fig. 1.
Fig. 3 is a camm G, A is the crank in this arrangement, the lever B is continued
at an angle beyond the pedal pin, at the extremity of the lever a pin is fixed upon
which a roller works which travels round the groove of the camm thus giving the
extension and return.
Fig. 4 is a camm in section.
Fig. 5 is a smaller camm H in this arrangement we attach another lever J to
the crank A. another lever K is attached to the levers B & J. a pin fixed to the
end of the lever J upon which a roller works which traveling round the groove
of the camm, thus giving the extension and retnrn.
Dated this 10th day of June 1891.
THOMAS HENRY BROOKS,
FRANK GEORGE HAMPSON,
Applicants.
COMPLETE SPECIFICATION.
Improvements for Increasing the Speed of Velocipedes by the Aid
of a Crank with an Extending Lever or Levers.
We THOMAS HENRY BROOKS 24 Handforth Road Brixton Engineer in the
Parish of Lambeth London FRANK GEORGE HAMPSON 21 Doris Street
Kennington Engineer in the Parish of Lambeth London 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 improvements in the crank mechanism of bycles
trycicles and similar vehicles and its object is to give the advantage of a long crank
during the down stroke of the pedal which in the case of cycles driven by a wheel
and chain mechanism will allow of a higher gearing than is practicable with the
ordinary crank and consequently an increase of speed is obtained and in the case
of cycles having their cranks fixed to the driving wheel spindle a greater crank
power is obtained while in each case the actual travel of the pedal is similar to
the ordinary crank and pedal arrangement. We will discribe our invention as
D

page_text: applied to a safety bicycle referring to the drawings left with the Provisional
Specification.
Fig. 1, E is a fixed eccentric with its full part looking forward and occupys the
position of the ordinary bottom brackett or crank spindle bearings, a strap D is
fitted to its outter diameter, the eccentric and strap being grooved to recive steel
ball for the purpose of reducing friction and is also made adjustable, the connecting
rod C engages with the eccentric strap D and the lever B by means of adjustable
ball joints, the other end of the lever B is attached to the crank A by means of
an adjustable ball joint, the pedal is attached to the same end of the lever B with
which the connecting rod engages, the eccentric being fixed in the manner shown
causes the pedal lever B and the pedal to extend from the crank spindle during
the down stroke and to return during the up stroke, thus giving the advantage of
a long crank the motion of the pedal experienced by the rider being similar to those
attached to ordinary cranks.
Fig. 1 shows the pedal lever B extended, the dotted lines indicate its return.
Fig. 2 is section of Fig. 1.
In Fig. 3 it will be seen that a large cam G may be employed instead of an
eccentric, the lever B having an adjustable ball roller fitted to it which, engaging
with the cam G gives the extention and return motion to the pedal lever as
discribed.
Fig. 4 is section of Fig. 3.
In Fig. 5 we employ a smaller cam H, another lever J is fitted to the crank A,
the lever or connecting link K engages with the levers B and J an adjustable ball
roller is pivoted at the joint which connects the levers K and J the said roller
engaging with the cam H, it will be seen by referring to the drawing that although
a smaller cam is used than is shown in Fig. 3 the arrangement of the levers B
and and K gives a similar extention and return to the pedal lever as discribed.
Referring to the drawings accompanying this Complete Specification Fig. 6
shows a tooth wheel L, which takes the place of either eccentric or cam and
contains within itsself the adjustable ball bearing for the crank spindle, M is a
simlar tooth wheel having the same number of teeth as the fixed wheel L and is
pivoted upon the arm of the crank so as to be propperly in gear with the wheel L,
the connecting rod C engages with the lever B and a pin which is fixed to and projects
from one side of the wheel M, by referring to the drawing it will be readily
understood that a similar extention and return is given to the pedal lever B as
befor discribed.
In Fig. 7 a sliding block N is substituded for the lever B and slides along the
arm of the crank and can be opperated by the wheels Land M or the cams G
and H or the eccentric E the wheels L and M can be pivoted eccentrically so as to
give a quick return to the pedal lever B or the sliding block N.
Having now particularly discribed and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what we
claim is
(1) The combination of a crank A having a lever B attached by means of an
adjustable ball joint said lever to extend from the crank spindle during the down
stroke and to return during the up stroke actuated by a fixed eccentric E in the
manner and for the purpose discribed.
(2) The combination of a crank A having a lever B attached and a cam G
containing the adjustable ball bearings for the crank spindle said lever opperated
by said cam in the manner and for the purpose discribed.
(3) The combination of a crank A having two levers B and J attached a lever
or link K engageing with the levers Band Ja cam H (Fig. 5) containing the
adjustable ball bearing for the crank spindle said levers opperated by said cam in
the manner and for the purposed discribed.
(4) The combination of a crank A having a lever B attached and two geared
wheel L and M (Fig. 6) the wheel L containing the adjustable ball bearing for

page_text: the crank spindle said lever actuated by said wheels in the manner and for the
purpose discribed.
(5) The combination of a crank A having a sliding block N (Fig. 7)
attached said sliding block opperated by the wheels L and M or the cams G
and H or the eccentric E in the manner and for the purpose specified.
Dated this 30th day of November 1891.
THOMAS HENRY BROOKS,
FRANK GEORGE HAMPSON,
Applicants.