An Improved Valve Cap for Pneumatic Tyres, and other Pneumatically-inflated Capacities.
Year: 1897

page_text: Date of Application, 17th Aug., 1897-Accepted, 25th Sept., 1897
COMPLETE SPECIFICATION.
An Improved Valve Cap for Pneumatic Tyres, and other
Pneumatically-inflated Capacities.
1, JOHN ADAM STEURER Physician of 229, Broadway, New York, in the
County and State of New York, United States of America; 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 closures for valve stems and has reference more par-
ticularly to efficiently closing the stems of valves used with pneumatic wheel tyres.
To this end my Invention consists in the construction hereinafter set forth and
claimed.
My invention will be understood by referring to the accompanying drawing in
which Figure 1 is a central vertical section of a valve apparatus embodying my
Invention. Figure 2 is a detail sectional view of the cap. Figure 3 is a detail
sectional view of the valve. Figure 4 is a face view of the portion of the valve
which comes against the valve seat; and Figure 5 is an enlarged central vertical
section similar to the section shewn in Figure 1 but illustrating the parts on an
enlarged scale to more clearly bring out the Invention.
Heretofore caps for bicycle tyre valves have been provided with a rubber
facing inside, which is rigid therewith, and consequently when the cap is turned,
rotates with the cap, and is thereby cut and worn to such an extent as to rapidly
deteriorate so that after a short season of use the cap becomes valueless to seal the
valve and is especially dangerous to use by reason of the fact that when the
valve-seat comes into the rubber, the rubber, when the cap is screwed down,
extends so far into the valve-seat as to touch the rod or stem which operates the
inner valve, so that the tyres so provided with these defective valve-caps become
after a short time very insecurely sealed, thereby leaking rapidly. My invention
is designed to obviate these defects by providing the cap with a loosely fitting
removable valve which will not turn with the cap when the same is screwed
down, and consequently will not cut or wear away to such an extent as to render
it leaky or bring it in contact with the stem of the inner valve.
In the drawing, a is the ordinary tube or hollow stem leading from the
d is
pneumatic tyre, and is provided with the usual seat b and screw-thread c.
the cap which is provided with a screw-thread e and above the topmost screw-
thread is enlarged laterally to form an enlarged chamber f in which the valve
can freely oscillate. The cap is pierced at the top with an aperture 9 for the
passage of the valve stem. The valve is shown as consisting of a head h faced
with a soft packing i of caoutchouc or other material, and provided with a rear-
wardly extending stem ; whose end k is preferably milled. The head h with its
facing of rubber is of considerably less diameter than the diameter of the recess
or chamber f, leaving small spaces between its edge and the inner face of the
wall of the chamber f. The head and its facing are, however, small enough to
pass through the portion of the cap wherein the screw-threads e are formed and
are preferably made as shown of just sufficient size for the rubber when it has
been well seated by pressure to engage the lands of the screw-thread, so that when
it is desired to remove the valve to replace it with rubber, it can be readily done

page_text: by forcing it downward through the cap and at the same time turning it so as to
engage the rubber with the screw-thread, thus screwing it out. When the valve
is in place in the head, the cap may be removed and by reason of the fact that the
uppermost screw-thread forms a sort of ledge the valve will not fall out of the
cap and the cap may be shaken about or dropped or otherwise handled without
ejecting the said valve from the cap, the most efficient means of taking out the
valve being to seize the stem, press the stem downward, and at the same time
rotate it so that the rubber will engage the screw-thread and thus screw the valve
out of the cap. With valves constructed as described and shown, it is wholly
unnecessary to provide any other means for retaining the valve in the cap than
the slight ledge afforded by the screw-threads, and consequently a considerable
space may be left around the valve stem between the valve stem and the sides of
the aperture g, so that the valve may freely vibrate in the head and will be thereby
more apt to catch on the ledge.
When it is desired to close the tube or stem a after pumping air therein, the cap
is placed upon the said stem and screwed down, and as soon as the facing of the
valve comes against the valve seat, the valve will remain stationary, and the head
being turned, will bear the valve down firmly upon its seat, thereby sealing the
stem.
I am aware that it is not new to provide a valve cap with an enlarged recess
above the screw-threads. I am likewise aware that it is not broadly new to
provide a valve stem with a cap containing a faced valve which is secured therein
by forming a shoulder on its stem. I am likewise aware that it is not new to
provide a valve cap with a reciprocating valve secured in place by a nut on the
stem, and consequently I do not claim such structures.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare, that, what I
claim is:-.
T
A
1. In an apparatus for sealing hollow valve stems, the combination of a cap
for engaging with the said stem provided with an internal ledge and an aperture,
of a valve located in the said cap above the ledge and provided with a stem
extending through the aperture, the said valve being freely movable in the said
cap and being wholly unsupported therein save by the ledge aforesaid, substantially
as described.
2. In an apparatus for sealing valve stems, the combination of a cap provided
with means for engaging with the stem, and provided with a ledge and aperture,
of a valve located in the cap and provided with a stem extending through the
aperture, the said valve being freely rotatable and vibratable in the said head and
sufficiently small to pass through the head at the place where the ledge is located
and being wholly unsupported in the said cap save by impingement upon the said
ledge.
3. In a means for sealing valve stems, the combination of a cap provided with
screw-threads for engaging with the valve stems and with a recess above the screw-
threads of greater diameter than the internal bore of the cap where it is screw-
threaded, and a valve freely movable in the said head and wholly unsupported
therein except when it impinges against the screw-threads.
Dated this 17th day of August 1897.
A. M. & WM. CLARK,
53 Chancery Lane, London, Chartered Patent Agents.