Improvements relating to Velocipedes.
Year: 1889

page_text: Date of Application, 17th Dec., 1889
Complete Specification Left, 17th Sept., 1890-Accepted, 18th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements relating to Velocipedes.
I, JOHN BOYD DUNLOP, of 50 Gloucester Street, Belfast, Ireland, Veterinary
Surgeon, do hereby declare the nature of this invention to be as follows:-
My invention relates to the employment of a yielding framework at the front portion
of velocipedes for minimising the vibration and shock usually experienced by riders
owing to the varying position of the front or pilot wheel-caused by the inequalities of
the road surface--and consequent vibration which is transmitted to the hands and arms
of the rider through the steering post or handle bar socket.
In accordance with my invention I make use of flexible flat bars of spring steel
or similar flexible metal or material which connect the steering post or handle bar
socket with the front wheel which latter is maintained a suitable distance in advance of
the steering post. The ends of the flexible flat bars-which latter are preferably
horizontal and placed one above the other on each side of the wheel with a space
intervening are bolted, rivetted or otherwise secured to vertically disposed stays or
supports which may be also of flexible metal or material; or, said stays or supports
may be rigid if so desired.
I wish it to be understood that I do not confine myself to the particular arrangement
or position of the flexible flat bars aforesaid as same may be varied without departing
from the main features of my said invention.
Dated this 17th day of December 1889
JAMES
STEVENSON,
20, High Holborn, London, W.C., Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Velocipedes.
1. JOHN BOYD DUNLOP of 50 Gloucester Street, Belfast, Ireland, Veterinary Surgeon,
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:
My invention relates to the employment of a yielding frame work at the front portion
of velocipedes for minimising the vibration and shock usually experienced by riders
owing to the varying position of the front or pilot wheel caused by the inequalities of
the road surface and consequent vibration which is transmitted to the hands and arms
of the rider through the steering post or handle bar socket.
In accordance with my invention I make use of flexible flat bars of spring steel or
similar flexible material which connect the steering post or handle bar socket with the
front wheel. The flexible flat bars are placed horizontally or inclined one above the
other, either above or on each side of the front wheel, with a space intervening, and
are bolted, rivetted or otherwise secured to lugs or brackets on vertically disposed
stays or supports.
In order that my invention may be the better understood I have appended the
accompanying sheet of drawings wherein Figure 1 is a side elevation of the flexible
flat bars arranged above the front wheel and Figure 2 a side elevation of same
disposed on each side of the front wheel. Figure 3 is a plan of the arrangement shewn
at Figure 1 and Figure 4 a plan of that shown at Figure 2.
In Figures 1 and 3, H is the steering post connected to the front fork F by
the flat bars of spring steel S. These flat bars are arranged in pairs, one above the
other the ends of the bars being bolted, rivetted or otherwise secured to lugs a on the
steering post H and lugs on the front fork F.

page_text: In addition to the first above referred to pair of spring bars S, I employ another
pair S2 parallel to the first pair S and at any suitable distance from same, this second
pair being similarly disposed, and secured in position by riveting or bolting to the
lugs or brackets a, b, of the steering post H and front fork F.
In Figures 2 and 4, F is the front fork, FL the steering post having a forked
extension, B; S is the lower pair of spring bars each bar being disposed on each side
of the wheel and bolted to the lugs a on the steering post extension B and to the lugs b
on the front fork F. The upper pair of spring bars S is arranged in a similar manner
parallel to the lower pair S and at a suitable distance therefrom. The front fork or
vertical support F may be either rigid or it may consist of spring steel or like flexible
material.
From the foregoing it will be seen that the flexible spring bars S, S², whilst
possessing sufficient lateral strength to ensure perfect steering, will allow a certain
amount of rise and fall of the front fork corresponding to the vertical motion of the
front wheel, thereby intercepting the vibration which otherwise would be communicated
to the steering post H. Moreover by the employment of this arrangement of spring
bars, the steering post H is maintained under all conditions parallel to the front fork F.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I wish it to be understood
that I am aware it has already been proposed, prior to the date of my invention to
employ bars of spring steel for intercepting vibration from the front wheel and I
therefore make no claim in respect thereof per se but what 1 claim, is:-
First. In velocipedes the combination of a steering post with or without a forked
extension, flexible or rigid fork carried upon the axle of the front wheel, parallel spring
bars arranged n pairs at suitable distances from cach other and secured to lugs or
brackets on the steering post or extension and front fork substantially as and for the
purposes herein set forth.
Secondly. The improvements in velocipedes substantially as herein set forth and
shown in the accompanying drawings.
JAMES STEVENSON,
Gray's Inn Chambers, 20, High Holborn, London, W.C., Agent for Applicant.