Improvements in or relating to Valves for Pneumatic Tyres.
Year: 1897

page_text: Date of Application, 3rd May, 1897-Accepted, 25th Sept., 1897
Improvements in or relating to Valves for Pneumatic Tyres.
A communication from GERARDO DA PRATO, of Pescantina, Province of Verona,
in the Kingdom of Italy.
I, ALFRED JULIUS BOULT, of 111 Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The present invention relates to valves in connection with the tyres of cycles
and other vehicles, which enables an air-tight closing of the valve to be effected.
In the acompanying drawings
Fig. 1 is an elevation partly in section of a valve according to the present
invention applied to a pneumatic tyre.
Fig. 2 is an inverted plan, the right hand half of the disc D being omitted.
Fig. 3 is an elevation partly in section of the cap closing the valve.
Fig. 4 is an elevation partly in section of a nut for connecting the pump-tube
to the valve.
Fig. 5 is an elevation partly in section of the nut connecting the valve to
the rim.
Fig. 6 is an elevation partly in section and a plan of the nut for fixing the valve
to the rubber tube and keeping it in place.
Fig. 7 is an elevation and plan of the metallic plate serving as a washer.
The improved valve is elegant in appearance and easy to apply to the air
chamber of the tyre, and has the further advantage of enabling air to be intro-
duced into the pneumatic tyre with a very slight effort.
This is effected in almost the same manner as in other valves with the difference
that in the present valve there is practically no resistance or back pressure to the
operation of the pump, and that by pressing a small tube the inner pressure can
be regulated enabling the desired amount of air to escape.
In the above figures A represents the cylindrical tube of the valve screw-threaded
on its outside throughout the whole of its length and terminating at the bottom in
a flange or enlarged portion recessed on its under side and having a raised upper
portion a B represents a circular disc or core of elastic rubber or the like placed
in the above mentioned recess of the part A; C represents a cylindrical tube intro-
duced into the inner tubular part of the lower portion of A and serving to hold in
place by its flanged extremity the rubber disc or washer B, 1) is a dise with a
flanged edge and is supported in an annular crown or dise E, which has inclined
sides, and is provided with a circular central opening and with a series of small
holes on its circumference. This crown is secured between the inner edge of the
lower flange of the part A and the rubber dise B and retains in its interior the
metal-disc D. F is a tube placed in the interior of the outer tube X and is pro-
vided at its lower end with a flange and two lateral openings f having the shape of
a conic section. This tube serves to maintain the disc D against the edge of the

page_text: annular crown E when the pressure of air in the interior of the tyre pushes it
against the rubber packing.
G is a metal plate serving as a washer between the tyre P and the nut H, of
Fig. 6. I is a nut serving to secure the valve to the rim of the wheel. L is a cap
for closing the valve, and M is the screw nut for connecting the pump-tube to the
valve. r is the rim of the wheel.
The working of the valve is as follows:-
Air, introduced by means of a pump, enters through the upper portion of e
tubes A and F and presses down the disc 1) into the position shown in Fig. 1.
Owing to the descent of the disc the injected air enters the tyre P' through the
series of holes in the annular crown E. As soon as the pump ceases working, owing
to the reaction or back pressure of the air in the tyre, the disc D is immediately
pressed upwards towards the top and strongly compresses by its edge the rubber
washer B; thereby effectually closing the valve against escape of air from the
tyre.
If it is desired to deflate the tyre, it is sufficient to press on the tube F, and cause
the disc D to descend, and the air will immediately escape from the interior of the
tyre through the holes of the annular crown, E.
a the
The invention therefore chiefly relates to the automatic closing of the valve, by
means of the internal air-pressure alone, and consists in placing the closing device
in the interior of the tyre and in providing the device with a raised edge
back of the enlarged portion or flange of the tube A, which enlarged portion
enable the immediate attachment of the valve to the tyre to be effected by means
of the metal plate G and nut II.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondent and in what manner the
same is to be performed, I declare that what I claim is :-
1. A valve for pneumatic tyres closing automatically by the internal air
pressure, substantially as described.
2. In a valve of the character described, a closing device arranged in the interior
of the tyre substantially as described.
3. In a valve of the character described, a coupling nut such as M for connecting
the tube of the pump, with the valve, substantially as described.
4. In a valve of the character described, a tube having an enlarged portion or
flange, recessed in its under surface and provided with a projecting part such as a
on its upper face, to enable the valve to be directly applied to the tyre by means of
a metallic plate and a nut, substantially as described.
5. In a valve of the character described, the combination of tubes such as I'
and C, an annular crown such as E, and elastic washer such as B with a disc such
as D, substantially as described.
6. The combination and arrangement of parts constituting the complete valve
for pneumatic tyres, substantially as described and illustrated in the accompanying
drawings.
BOULT & WADE,
Agents for the Applicant.