Improvements in Apparatus for Inflating Pneumatic Tyres.
Year: 1896

page_text: Date of Application, 9th June, 1896
Complete Specification Left, 9th Mar., 1897-Accepted, 15th May, 1897
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Inflating Pneumatic Tyres.
We, BENJAMIN RATCLIFFE ADKINS, of 14 Albion Road, College Park,
Lewisham, in the County of Kent, Engineer, and CHARLES WINDSOR, of
Tressillian Road, Brockley, in the County of Kent, Gentleman, do hereby declare
the nature of this invention to be as follows:-
This invention has reference to that kind of apparatus for automatically
inflating a pneumatic tyre and maintaining a practically constant pressure therein
during the rotation of the wheel to which the tyre is applied, according to which
air is drawn past a suction valve into a pump cylinder attached to the wheel rim
and is delivered into the pneumatic tyre past a delivery valve by a piston the rod
of which extends partly through the tyre and is attached to the outer peripheral
or tread portion thereof, the arrangement being such that whilst the tyre is only
partly inflated, the piston will be moved inward in its cylinder and air therein will
pass to the outer side of the piston, each time the portion of the tread of the tyre
to which the outer end of the piston rod is attached, is moved inward by pressure,
against the ground upon which the wheel runs and the air that has thus passed to
the outer side of the piston will, upon further rotation of the wheel, be forced into
the pneumatic tyre past the delivery valve by the outward movement of the
piston caused by the pressure of the air in the tyre acting against a larger
area than that of the piston, the supply of air automatically ceasing when the
tyre has been sufficiently inflated. The terms "inner" and "outer" as herein
used in connection with the pump cylinder, piston and piston rod, have relation to.
the centre of the wheel to which the apparatus is applied.
Now this invention has reference to various improvements in inflating apparatus
of the kind referred to, designed to simplify the construction thereof and improve
its efficiency and working.
According thereto the pump cylinder is provided at its closed inner end with
an air inlet nozzle controlled by a suction valve consisting of a perforated piece of
sheet material such as leather or india rubber that is located within the cylinder, is
formed with perforations out of line with the bore of the nozzle and is held against
the inner end of the cylinder by a holding device that is fixed within the cylinder
without the aid of screws, or like fastenings, extending to the exterior thereof. In
one arrangement the suction valve is formed of a triangular shaped piece of
leather formed with three perforations having their axes in a circle concentric to
but at some distance from the air inlet opening, the valve being held in place by a
triangular shaped metal frame fixed in place by forcing its three ends into an
undercut recess in the corresponding end of the pump cylinder. Their inlet
nozzle, which is externally screw threaded to enable an ordinary air pump or
inflator to be screwed thereto for partly inflating the tyre if necessary at starting,
is normally provided with a screw-cap formed at one end with inclined air passages
that are arranged about the axis of the cap and communicate with the interior
thereof. Between the screw cap and the cylinder is a packing ring of suitable
material such as leather or india-rubber. Upon the cap is screwed an adjustable
air closure and filtering device that is preferably made in the form of an internally
screw threaded nut with a transverse division that is perforated at the centre and

page_text: which divides the interior of the nut into two compartments. The compartment
next the screw cap is provided with a washer of packing material which when the
nut is tightened up, is compressed between the division in the nut and annula
ridges on the exterior of the screw cap so as to then effectually close the air
inlet passages in the latter. The outer compartment through which the air draw
into the purap cylinder on the suction stroke of the pump piston passes, is charged
with filtering material such as cotton wool that is retained in place by a removable
perforated metal dise forced in the onter compartment. The nut is prevented from
leaving the screw cap by metal clip picces that may advantageously be formed in
one piece with the said perforated dise and has its free ends extending into an
annular groove in the screw cap.
The outer end of the pump cylinder is screwed into a valve box and abuts
against a packing ring in a perforated valve plate that is also screwed in the valve
box and between which and the outer end of the valve box is clamped the main air
or delivery valve which consists of a ring of material such as leather or india
rubber provided at its central part with a tubular portion fitting the piston rod
which works through it and the valve plate. The valve plate and valve are each
formed with air passages, those in the valve being arranged between those in the
plate and with their axes in a circle of different diameter to that containing the
axes of the holes in the plate so that the holes in the one can never be accidentally
placed over the holes in the other. The holes in the valve are opposite an annular
recess in the end of valve box which is provided with a tubular extension with
which the said recess communicates by inclined air passages.
The air pump cylinder with valves as described is connected to a pneum itic tyre
and a wheel rim by being screwed upon the inner end of a tubular stem whica
passes through the wheel rim and is provided at its outer end with a heal between
which and a metal washer thereon, the air tube of the tyre, or simply the tyre in
the ease of a single tube tyre is tightly clamped by a ut, a tight joint being
produced between the stem and valve box by a packing ring. The pamp piston is
constructed with a cupped leather ring held in place by a nut screwed in a boss
on the piston in which is screwed the inner end of the piston rod which extends
outward through the tubular stem which it fits and in which are air ways in com-
tnunication with the interior of the tyre. At its outer end the piston rod is
connected to a stem that extends inwardly through the outer periphery of the
air tube and is formed on a plate that is curved both longitudinally and
transversely and between which and a washer the portion of the air tube is
tightly clamped preferably by rivetting or flanging the edge of the boss tightly
over the washer which may also be curved in a longitudinal and a transverse
direction.
To enable the piston rod to move and accommodate itself to longitudinal and
transverse movements of the part of the tyre to which it is attached, the piston
rod is hinged or jointed to the plate clamped to the outer periphery of the tyre so
that it can turn relatively thereto in the longitudinal direction, and the tubular
stem connected to the inner periphery of the tyre and the valve box and cylinder
connected to such stem are so mounted and arranged that they can rock in all
directions on the wheel rim. The outer end of the piston rod may for the purpose
mentioned be connected to the stem of the plate to which it is attached by a
tongue and groove joint through which passes a pivot pin one end of which is
screwed into the stem and then rivetted over or expanded to prevent it becoming
loose. To enable the stem carrying the valve box and attached parts to rock it is
provided at the inner periphery of the wheel rim with a screw nut having a
spherical outer surface that bears against a washer of suitable elastic material for
example india rubber interposed between it and the wheel rim and on the corre-
spondingly formed surface of which it can rock, the side of the nut that serves to
clamp the said tubular stem to the air tube, being also made of rounded or convex
form on the side next the wheel rim to permit it to rock thereon, and the hole
in the wheel rim through which the stem passes, being made sufficiently large

page_text: to enable the stem to cant in any direction. The said stem may be formed
with flats at two opposite parts to facilitate screwing together of various parts.
ณ
As will be obvious some of our improvements may be used without the others,
and some of the parts may be modified to adapt them to different constructions of
pneumatic tyres. Thus in the case of a single tube tyre the plate connected to the
other peripheral portion of the tyre may be arranged to be embedded in the
fabric of the tyre during the formation thereof. In all cases where it is desired
to clamp a packing ring, valve, air' tube or the like of yielding material air tight
between two metal parts, it is advantageous to provide one of the metal parts
with a ridge or ridges. The other metal may be provided with a corresponding
groove.
Improvements in Apparatus for Inflating Pneumatic Tyres.
We, BENJAMIN RATCLIFFE ADKINS, of 14 Albion Road, College Park,
Lewishamn, in the County of Kent, Engineer, and CHARLES WINDSOR, of
71 Tressillian Road, Brockley, in the County of Kent, Gentleman, 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:-
In the Specification of another application for Letters Patent filed by us dated
16 April 1896, No. 8045 we have described an apparatus for automatically inflating.
a pneumatic tyre and maintaining a practically constant pressure therein during
the rotation of the wheel to which the tyre is applied, wherein air is drawn past a
suction valve into a pump cylinder attached to the wheel rim and is delivered into
the pneumatic tyre past a delivery valve by a piston the rod of which extends
partly through the tyre and is attached to the outer peripheral or tread portion
thereof, the arrangement being such that whilst the tyre is only partly inflated,
the piston will be moved inward in its cylinder and air therein will pass to the
outer side of the piston each time the portion of the tread of the tyre to which the
outer end of the piston rod is attached, is moved inward by pressure against
the ground upon which the wheel runs and the air that has thus passed to the
outer side of the piston will, upon further rotation of the wheel, be forced into
the pneumatic tyre past the delivery valve by the outward movement of the piston
caused by the pressure of the air in the tyre acting against a larger area than that
of the piston, the supply of air automatically ceasing when the tyre has been
sufficiently inflated. The terms "inner" and "outer" as herein used in connection
with the pump cylinder, piston and piston rod, are employed to indicate the
position of these parts relatively to the centre of the wheel to which the apparatus
is applied.
Now this invention has reference to various improvements in inflating apparatus
of the kind referred to, designed to simplify the construction thereof and improve
its efficiency and working, as we shall now proceed to explain by reference to the
accompanying drawings wherein
Fig. 1 is a longitudinal section on. the line vv of Fig. 2, and Fig. 2 an end
elevation partly in section on the line ww of Fig. 1, showing to an enlarged scale,..

page_text: inflating apparatus of the kind referred to applied to a wheel rim and embodying
our present improvements.
Figs. 3, and 5 are cross sections on the lines xx; yy; and 2 z respectively of
Fig. 1.
According to this invention, the pump cylinder 1 is provided at its closed inner
end with an air inlet nozzle 2 controlled by a suction valve 3 consisting of a
perforated piece of sheet material such as leather or india rubber that is located
within the cylinder, is formed with perforations 3 out of line with the bore 2 of
the nozzle and is held against the inner end of the cylinder by a holding device
that is fixed within the cylinder without the aid of screws, or like fastenings,
extending to the exterior thereof, so as to avoid all liability of air leakage. In
the arrangement shown the suction valve 3 is formed of a triangular shaped piece
of leather formed with three perforations 3ª having their axes in a circle concentric
to but at some distance from the air inlet opening 2 (Fig. 3), the valve being held
in place by a triangular shaped metal frame 4 fixed in place by forcing its three
ends 4 into an undercut recess 1" in the corresponding end of the pump cylinder.
The air inlet nozzle 2, which is externally screw threaded to enable an ordinary
air pump or inflator to be screwed thereto for partly inflating the tyre if necessary
at starting, is provided with a screw-cap 5 formed at one end with inclined air
passages 5" that are arranged abcut the axis of the cap and communicate with the
interior thereof. Between the screw cap 5 and the cylinder 1 is a packing ring 6
of suitable material such as leather or india rubber. Upon the cap is screwed an
adjustable air closure and filtering device 7 that is preferably made in the form of
a screw threaded nut with a transverse division 7 that is perforated at the
centre 7 and which divides the interior of the nut into two compartments. The
compartment next the screw cap 5 is provided with a washer 8 of packing material,
which, when the nut is tightened up, is compressed between the division 7a in the
nut and annular ridges 5 on the adjacent end of the screw cap 5 so as to then
effectually close the air inlet passages 5" in the latter. The other compartment
through which the air drawn into the pump cylinder 1 on the suction stroke of the
pump piston passes, is charged with filtering material 9 such as cotton wool,
retained in place by a removable perforated metal disc 10 which is forced into the
said compartment. The nut 7 is prevented from leaving the screw cap 5 by metal
clip pieces 10 that may, as shown, be formed in one piece with the said perforated
disc 10 and which have their free ends 10 extending into an annular groove 5° in
the screw cap 5.
The outer end of the pump cylinder 1 is screwed into a valve box 11 and abuts
against a packing ring 12 in a perforated valve plate 13 which is also screwed into
the said valve box and between which and the outer end portion of the valve box
is clamped the main air or delivery valve 14. This valve consists of a ring of
material such as leather or india rubber provided at its central part with a tubular
portion 14 that fits the piston rod 15 which works through it and the valve
plate 13. The valve plate 13 and valve 14 are formed with air holes or passages 13ª
and 14 respectively (Fig. 4) those (14) in the valve being arranged between
those (13) in the plate and with their axes in a circle of different diameter to that
containing the axes of the holes 13 so that the holes in the one can never be
accidentally placed over the holes in the other. The holes 14ª in the valve 14 are
opposite an annular recess 11 in the end of the valve box.11.which is provided
with a tubular extension 11 with which the said recess communicates by inclined
air passages 11º.
The air pump cylinder 1 with valves 3 and 14 as described is connected to a
pneumatic tyre 16, 16 and a wheel rim 17 by being screwed upon the inner end of
attubular stem 18 which passes. through the wheel rim and is provided at its outer
end with a head 18" between which and a metal washer 18 thereon, the air tube 16
of the tyre, or simply the tyre in the case of a single tube tyre, is tightly clamped
by a nut 19. A tight joint is produced betwee the stem 18 and valve box 11 by
atpacking ring. 20..

page_text: The pump piston 21 is constructed with a capped leather ring 22 held in place
by a nut 23 screwed on a boss 21 on the piston. The inner end 15 of the piston -
rod 15 is serewed into the said boss, the rod extending outward through the
tubular stem 18 which it fits and in which are air ways 18° (Fig. 5) in communication
with the interior of the tyre. At its outer end the piston rod 1 is connected to a
stem 24 that extends inwardly through the outer periphery of the air tube 16
and is formed on a plate 24 that is curved both in a longitudinal direction and
in a transverse direction, as shown, and is as heretofore, of larger area than
the pump piston 21. Between this plate 24 and a washer 25 the air tube 16
is tightly clamped, as hy riveting or flanging (as shown) the edge 24° of the
boss 24 carrying the stem 24, tightly over the washer 25 which may also be
curved in a longitudinal and transverse direction when the plate 24 is so
curved.
The connection between the piston rod 15 and the air tube 16 is covered by the
tyre cover 16 which may he of any suitable construction. 26 and 26" are pieces
of canvas secured to the air tube to strengthen it where it is secured to the stem 18
and plate 24 respectively.
To enable the piston rod 15 to move and accommodate itself when in use, to
longitudinal and transverse movements of the part of the tyre to which it is
attached, its outer end is hinged or jointed to the plate 24 that is clamped to the
outer periphery of the tyre so that it can turn or move relatively to such plate in
the longitudinal direction, and the tubular stem 18 carrying the valve box 11 and
attached parts is so mounted and arranged that it can rock or oscillate in all
directions on the wheel rim 17. The outer end of the piston rod may, for the
purpose mentioned, be connected to the stem 24 of the plate 24 by a tongue and
groove joint as shown at 27 (Fig. 2) through which passes a pivot pin 28 one end
of which is screwed into the stem and then riveted over or expanded to prevent
it becoming loose. To enable the stem 18 to rock or oscillate on the wheel rim, it
is provided at the inner periphery of said rim with a screw nut 29 having a
spherical outer surface that bears against a washer 30 of 'suitable elastic material
for example india rubber, which is interposed between it and the wheel rim and on
the adjacent surface of which it can rock or oscillate in any direction. The side
of the nut 19 that serves to clamp the said tubular stem to the air tube 16, being
also made of rounded or convex form on the side next the wheel rim so as to permit
it to rock thereon, the hole 17 in the wheel rim 17 through which the stem passes,
being made sufficiently large to enable the stem to oscillate in any direction, to the
required extent. The said stem 18 may be formed with flats at two opposite parts
to facilitate the screwing together of the various parts.
With the arrangement described, it will be seen that when the wheel is in motion
and the tyre is partly deflated, the pisten will be alternately moved inward by
pressure of the tyre against the ground and immediately afterwards will be forced
outward by the pressure of the air within the tyre acting against the pedal plate 24,
so that assuming the enp 7 to have been partly unscrewed, air drawn into the
pump cylinder during one outstroke of the piston will be forced to the outer side
of the piston on the next instroke thereof and will then be forced into the tyre on
the next outstroke by the pressure of the air in the tyre acting on the pedal
plate 24, which is of greater effective area than the piston. This action will
continue until the tyre is fully inflated and only a slight inward movement of the
tyre is produced at the point of contact with the ground, whereupon further entrance
of air into the tyre will automatically cease after which the nut 7 can be screwed up
tight against the cap 5 to prevent any leakage of air at this point. To deflate the
tyre, all that is necessary is to parily unscrew the valve chamber 11 from the
stem 18. The volume of the air space, can be varied by using on the piston 21
nuts 23 of different diameters.
As will be obvious some of our improvements may be used without the others,
and some of the parts may be modified to adapt them to different constructions of
pneumatic tyres. Thus in the case of a single tube tyre the plate 24 connected to

page_text: the outer peripheral portion of the tyre may be arranged to be embedded in the
fabric of the tyre during the formation thereof. In all cases where it is desired to
clamp a packing ring, valve, air tube or the like of yielding material in an air
tight manner between two metal parts, it is advantageous to. provide one of the
metal parts with a ridge or ridges 5 that will become embedded in the yielding
material when the parts are pressed together. The other metal part may be
provided with a corresponding groove or not, as desired..
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. Tyre inflating apparatus of the kind herein referred to wherein the air pump
is adapted to be pivotally connected to a wheel rim so that it can rock or oscillate
thereon and the pump piston rod extending through the outer end of the pump
cylinder is hinged or jointed to the plate or device by which it is secured to the
outer peripheral or tread portion of the tyre, the arrangement being such that the
piston rod can accommodate itself to longitudinal and transverse movements of
the part of the tyre to which it is attached, substantially as described.
2. In tyre inflating apparatus of the kind herein referred to, the combination with
the hollow stem 18 that serves to carry the pump cylinder and connect the same
with a pneumatic tyre, of the nuts 19 and 29 having their adjacent ends of spherical
or rounded form, and the interposed washer 30, substantially as herein described
for the purpose specified.
3. In inflating apparatus of the kind herein referred to, a suction valve 4
consisting of a flat piece of elastic or flexible material formed with perforations out
of line with the bore of the air inlet nozzle and held at its edges against the inner
end of the cylinder by a holding device such as 4 that is fixed within the cylinder
without the aid of fastenings extending to the exterior thereof, substantially as
described and shown.
4. Apparatus of the kind herein referred to wherein the perforated air delivery
valve located at the outer end of the air pump and formed with a tubular portion 14*
is clamped in place between the grooved outer end portion of the valve box 11 and
a perforated valve plate 13 which is screwed into the said valve box and against
which the outer end of the pump cylinder bears, substantially as described and
shown.
5. The improved apparatus substantially as described and shown for inflating
pneumatic tyres.
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.