Improvements in Bicycles and Tricycles.
Year: 1890

page_text: Date of Application, 3rd Mar., 1890
Complete Specification Left. 24th Apr., 1890-Accepted. 24th Mav. 1890
PROVISIONAL SPECIFICATION.
Improvements in Bicycles and Tricycles.
WILLIAM HENRY PRESTWICH Photographer High Road Tottenham' N. EDWARD
PERCIVAL PRESTWICH Photographer High Road Tottenham N. we do hereby declare
the nature of this invention to be as follows:-
The nature of our improvements consists in providing means to prevent the excessive
vibration which occurs in ordinary bicycles and tricycles, when travelling over
inequalities of the road.
We accomplish our improvements by fitting a lever joint in each leg of the fork of
wheel, near to the axele, the lever is prolonged forward bearing on the axle, and is
continued backward beyond the joint in a horizontal direction forming a cantilever,
to which we attach helical springs connecting the ends of said levers to a suitable
point of the legs.
Dated March 3rd 1890
WILLIAM HENRY PRESTWICH.
EDWARD PERCIVAL PRESTWICH.
COMPLETE SPECIFICATION.
Improvements in Bicycles and Tricycles.
We, WILLIAM HENRY PRESTWICH, and EDWARD PERCIVAL PRESTWICHI, both of
High Road, Tottenham, in the County of Middlesex, Photographers, 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 a device for preventing the excessive vibration which
occurs in bicycles and tricycles when travelling over rough and stoney roads.
We attain the object of our invention by fitting a lever at or about the centre of
its length to each prong or leg of the fork adapted to carry the wheel, and by
mounting the axle of the wheel on the forward ends of these levers and by con-
necting the other ends of the levers to the prongs of the fork by helical or equivalent
springs in the manner illustrated by the accompanying drawing, in which Figure 1. is
a broken view in side elevation of the steering wheel of a safety bicycle or a tricycle
fitted with our invention and Figure 2. is a view in transverse sectional elevation
through the said wheel.
I
Throughout these views similar parts are marked with like letters of reference.
On to the end of each prong or leg of the fork X adapted to carry the steering or
other wheel Z is fulcrated by a "rule" or similar joint a a lever A. The forward
ends of these levers are adapted to carry the axle z of the wheel Z, and the rear ends
are connected with the prongs or legs a. a. of the fork X by helical or other suitably
shaped springs B. B. The levers AA are arranged to be as nearly as possible in the
horizontal plane in their normal position, and the rear ends are provided with
notches a etc., or their equivalents, whereby the points of attachment of the
springs B. B. thereto may be varied so as to increase or diminish the leverage, and
thus increase or decrease the tension of the said springs according to the movement
required by the condition of the roads, or the weight of the rider.
It will be understood that the joint a is of such a construction that it restricts the
movement of the lever with respect to the prong of the fork within certain
limits.
It will be seen that this invention is readily applicable to existing machines, and that
it forms an effective antivibration device, as it allows the wheel to rise to pass over
obstacles without lifting the main frame and weight of the rider.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
1st. The improvement in bicycles and tricycles constructed specifically as set forth.
2nd. In a velocipede mounting the steering or leading wheel on levers fulcrated to
the ends of the prongs of the fork adapted to carry the said wheel,and controlling the
motion of the said levers by springs acting between the prongs of the fork and the free
ends of the said levers, and capable of adjustment at their points of connection there-
with, as and for the purpose set forth.
Dated this 21th day of Anril 1890
WILLIAM HENRY PRESTWICH.
EDWARD PERCIVAL PRESTWICH.