Improvements in Bicycles and other Wheeled Vehicles.
Year: 1896

page_text: Date of Application, 1st May, 1896
Complete Specification Left, 29th Jan., 1897-Accepted, 1st May, 1897
PROVISIONAL SPECIFICATION.
Improvements in Bicycles and other Wheeled Vehicles.
I DENIS DOYLE Workhouse Youghal Co. Cork Workhouse Master do hereby
declare the nature of this invention to be as follows:-
Its object is to reduce jolting or vibration in moving on a rough or ordinary
road. This is effected by the attachment of an easier spring than those hitherto
in use between the frame & axle. This spring is preferably pneumatic being a
cushion, or a number of cushions placed one above another & held in position by a
pillar erected on said axle & passing up through a hole in frame in which it works
freely up & down. The cushions to be in the form of rings round this pillar,
communicating one with another & with a large air chamber fitted in a convenient
place in the frame. Instead of cushions a single tube may be brought round the
said pillar in spiral form and connected as before with an air chamber. The use
of this air chamber is to make the spring easier; that is to have a more uniform
resistance for a given extent of pressure. Thus without the chamber if
I press the spring suppose 3 inches the resistance increases from 150 to 280 lbs.
while with the chamber it increases only to 154 lbs. In the latter case a wheel
would descend into a rut without the rider scarcely perceiving it, whilst in the
former case the jolt would be considerable.
The strength of spring to be regulated by the air pump & this may be so
attached as to work automatically by the vibration when a certain degree of
slackness is attained & to remain at rest when the cushion is sufficiently inflated.
Dated this 29th day of April 1896.
I DENIS DOYLE Youghal Co. Cork, Workhouse Master 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 :-
Its object is to reduce vibration or jolting to a minimum by attaching pneumatic
or vacuum springs as hereinafter described.
The springs used in cycles and other wheeled vehicles may be classed into two
kinds viz. (1) those acting by tension & which sustain the weight of vehicle & load
by suspension (2) those acting by compression such as is used in carriages &
railway cars generally.
For the steel springs of the first class I substitute a vacuum spring shown ia
Fig. 1. It is formed like a bellows, made perfectly airtight by the leather of the
sides being covered over with a skin of india rubber, & held in proper shape by
the rings R R placed internally. By attaching an air pump to the valve V the

page_text: air can be almost entirely exhausted which causes both ends to be drawn together
by the force of atmospheric pressure: The area of the heads or ends, or the
sectional area of chest must be made large-in proportion to the weight to be
sustained so that the weight may be counterbalanced by the pressure of the
atmosphere in its lightest state. Thus if 4 stones is to be sustained the area of
head must be a little over 4 inches. This vacuum spring is mounted like an
ordinary spiral steel spring by inserting the hooks of frame in the eyes [ I at
-either end.
For the second kind of spring I substitute a cushion of compressed air
shown Fig. 2. It is constructed similar to the foregoing except that the
rings are fitted externally round the leather 11 of sides an india rubber
chamber being fitted internally to secure against the escape of air. The chest or
cushion communicates through opening O to chamber C in frame F..F. This
chamber is necessary to give the cushion the required degree of resiliency. It
may be as shown in the hollow of the frame or in any other convenient part of
the vehicle the larger it is the more resilient will be spring of cushion. By
attaching an inflator to valve V in frame F F the cushion can be inflated to the
required degree. This mounted on a bicycle (spring frame) where compression
springs are used or mounted on any other vehicle in place of the existing steel
springs will be a vast improvement in reducing vibration to a minimum: The
cushion must be inflated hard enough to suit load.
Having now particularly described and ascertained the nature of my said inven-
tion & in what manner the same is to be performed I declare that what I
claim is :-
1. The combination with a spring frame cycle or other wheeled vehicle of an
air cushion connected with an air chamber for increasing resiliency of same
substantially as described above.
2. The combination with a spring frame cycle or other wheeled vehicle of a
vacuum spring substantially as above described.
Dated 7th day of Januar 1002