Improvements in Pneumatic Wheel-centres
Year: 1897

page_text: Date of Application, 11th Dec., 1897
Complete Specification Left, 7th Oct., 1898-Aocepted, 3rd Dec. 1898
Date of Application, 11th Dec., 1897
Complete Specification Left, 7th Oct., 1898-Accepted, 3rd Dec. 1898
PROVISIONAL SPECIFICATION.
Improvements in Pneumatic Wheel-centres."
We, JOHN EVANS, of Cleveland House, Grange Town R.S.O., in the County of
York, and ROBERT WILLIAM HEALEY, Draughtsman, of 11, Middlesboro' Road,
South Bank, Yorkshire, do hereby declare the nature of this invention to be as
follows:
This invention consists of improvements in pneumatic wheel centres and has
for object to impart to wheels provided with solid or cushion tyres all the advan-
tages that result from the use of pneumatic tyres whilst ensuring them against
the disadvantages, such as side slipping and punctures, attendant thereon.
Although the invention is specially designed for use in bicycles and tricycles, it
is also applicable to other vehicles.
A pneumatic wheel centre according to this invention comprises a hub to
which the spokes or their equivalents are secured and which has a large central
aperture at each end; a casing around which the hub is intended to rotate and
which has also a large aperture at each end through which passes a spindle,
which can fall and rise therein and which is secured, so as to be incapable of
rotation, to the frame of the vehicle and is provided with a bore extending for
a short distance from one of its ends and containing an air valve; means for
preventing the casing and hub from moving laterally on the spindle and for pre-
venting the casing from rotating about the spindle; and a pneumatic
tube surrounding the spindle, supporting it within the casing, and connected
with the bore of the spindle so that when necessary it can be inflated through
the valve. Means may also be provided whereby the casing can be rigidly se-
cured to the axle in case the pneumatic tube burst and no fresh tube be available.
The hub may consist of two somewhat conical end pieces connected together by
a cylindrical piece and each having a central aperture of large diameter around
which is formed a race for bearing balls. The internal casing, which is prefer-
ably made of nickel steel, may also be cylindrical with conical end walls termi-
nating in cylindrical portions having right and left handed screw threads. The
other portion of the bearing for each set of balls is formed by a flange of suit-
able material such as case hardened steel, which is screwed upon the corres-
ponding end of the casing and which has an outer surface perpendicular to the
axis of the hub and is provided with an outwardly projecting pin, hereinafter
referred to.
The spindle may either be approximately straight or bent or cranked so that
when the spindle is in its highest possible position within the internal casing,
the middle of the spindle, around which the air-tube fits is centrally within the
casing. One end of the spindle may have a part made square in cross section
and the other be screw threaded and have fixed upon it a square nut, so that the
spindle will be prevented from rotating when these parts are fitted into the limbs
of the fork or corresponding portions of the frame of the vehicle, which should be
similarly formed.

page_text: On the part of square section and the nut of the spindle there may also be
fitted two cheeks stamped or otherwise tormed out of suitable material such as
case hardened steel, each of which has a vertical plane surface perpendicular to
the axis of the hub and adapted to fit close against the vertical surface of the
corresponding flange, whose pin may engage in a vertical slot in the cheek.
These cheeks may be limited as to inward movement by flanges secured to or
formed in one with the spindle; these flanges may be received in recesses in
the cheeks and have their inner faces flush with the inner faces of the cheeks,
but in the case of the driving wheel of a bicycle it is preferred to form the recess
for the flange at the chain-wheel end of the spindle, in the corresponding flange
of the casing. In order to enable the distance between the cheeks to be ad-
justed, the flange of the spindle adjacent to the aforesaid square nut is preferably
formed by a flanged or unflanged nut which is screwed upon the spindle before
the square nut is placed thereon. The cheeks and the vehicle frame may be
rigidly secured on the spindle by nuts, which force the cheeks tightly against
the flanges of the spindle.
The air or pneumatic tube is preferably made of such a shape, when the spindle
is practically straight, that, when it is inflated and, the bicycle or other vehicle
being unloaded, the spindle is in its highest possible position within the casing,
the lower part of the tube is of considerably larger cross section than the upper
part when, however, the spindle is bent or cranked as herein before described,
the tube may be such as to be, with the spindle in the position just referred to,
of equal cross section in its upper and lower parts. The tube may be constructed
in any suitable manner; e.g., it may be a tube of rubber with an outer casing
of strong thin fabric, a tube of rubber with inner and outer casings of fabric, a
tube of fabric coated outside with rubber, or a tube of fabric coated inside and
outside with rubber. The tube preferably fits tightly on the middle portion of
the spindle, which is preferably of such a cross section as to prevent the tube
from creeping or slipping round it. For this purpose its middle portion may
he concavo-convex with the convex surface either at the top or at the bottom,
the edges being suitably rounded; or its middle portion may have upper and
lower concave surfaces and somewhat resemble in cross section a double-headed
railway-rail placed on its side, the portion of the rear head below the axis of the
spindle being somewhat larger than the upper portion and projecting somewhat
rearwardly and the centre of the section being somewhat in front of the axis
of the spindle; again, the middle portion of the spindle may be somewhat tri-
angular in cross section, having a front surface being approximately vertical,
a lower surface being slightly concave and slightly inclining upwards, and an
upper surface with, a considerable downward inclination and forming with the
lower surface a sharper edge than the two other edges; furthermore, and
ticularly when the spindle is bent as hereinbefore described, the middle portion
may as a whole be somewhat downwardly and forwardly inclined and its upper
surface may have a flat or convex front portion and a concave or flat rear portion
and its lower surface a flat or concave portion and a concave or flat rear portion,
the upper and lower surfaces being joined by rounded surfaces.
par-
As an additional precaution against creeping a sheath of suitable material
such as steel and adapted to fit the middle of the spindle tightly may be built
in or secured to the pneumatic tube.
The connection between the interior of the pneumatic tube and the bore of the
spindle may be made in various ways. According to one construction there is
secured in the tube during its construction a short screw threaded pine having
on it two nuts, or a nut and a disc, and an intermediate washer: the disc or
corresponding nut is rigidly fixed on the end of the pipe and is fixed permanently
in position in the tube whilst the tube is being made, the wall of the tube being
clamped between it and the washer by the other nut. The outer end of the pine
is enlarged and externally screw threaded. Another pine, which may be flexible
or not, is screwed into or otherwise secured to the spindle its outer end is pro-

page_text: vided with a flange and a box-nut which is screwed upon the enlarged end of the
other pipe and produces a tight joint between it and the outer end of the spindle
pipe by means of an interposed piece of vulcanized rubber or soft metal or the
like.
According to another construction a flexible pipe is secured to the air tube and
terminates in a tubular and angular piece of suitable hard material such as metal
to which is pivoted a bridle shaped lever and which has a reduced free end form-
ing a shoulder. In the spindle there is secured a tubular piece, which has a
hole communicating with its bore and surrounded by a recess and which has an
outer end so curved that when the outer end of the piece attached to the flexible
pipe is inserted into the hole and the lever is forced down along the curved
surface a rubber washer placed on the outer end of the latter piece will be com-
pressed by the said shoulder so as to form an air tight joint. A notch is pro-
vided in the spindle piece, in which a projection on the lever engages when moved
into its extreme position.
According to another construction a flexible pipe permanently secured at one
end to the pneumatic tube is secured at its other end over the outer end of a
nipple secured in the spindle, the flexible pipe being wrapped with fine wire,
twine, or other suitable material and thereby forced into an annular groove or
annular grooves in the nipple. India-rubber solution may be used in making
the joint air tight.
The construction is preferably such that, when desired, on deflating the air
tube and removing the wheel centre from the frame and the cheeks from the
spindle the connexion between the bore of the spindle and the air tube can be
undone and the air-tube removed and another one put into its place through
one of the end apertures in the casing.
In order to enable the cheeks to be rigidly secured to the casing so as to render
the wheel serviceable when the air tube has burst and no duplicate is available,
each cheek may be provided with set screws and the adjacent flange with corre-
sponding tapped holes.
The valve employed in the spindle may be of any suitable kind. According
to one construction it comprises a cylindrical body that fits loosely in a recess in
the corresponding end of the spindle is tapped out to suit the screwed end of the
nozzle of an inflator and contains a piece of vulcanized rubber or soft metal such
as lead, tin, or white composition metal, shaped to allow the tapered end of the
nozzle to bed itself therein on being screwed up and thereby to form an air tight
joint. A plug may be normally screwed into the hole intended for the nozzle
and be attached to the adjacent cheek by a chain. A milled box-nut is screwed
on the outer end of the spindle and presses it may be by means of an annular
projection, against the valve and thereby forces it into its place. A hole is made
through this nut to allow the nozzle of the inflator to pass through. From the
cylindrical body there extends a tubular portion having near its outer end a
flange which fits in a larger portion of the bore of the spindle and between which
and the cylindrical body there is a rubber ring which is forced, by the said box-
nut, against a shoulder in the spindle, whereby an easily breakable air tight joint
is produced. Over the inner, and major part of the tubular portion there is
stretched an elastic tube, which is closed at its inner end, there covering the end
of the bore of the projecting tubular portion, and is secured at its outer end by
strong fine twine, wire or other suitable material wound round the tube in a
groove formed between the cylindrical body and an annular projection formed
on the projecting tubular portion. The elastic tube is perforated between its
inner end and the said annular projection, so that when air is pumped into
the valve it passes through the small hole at the inner end of the tubular portion,
under the elastic covering and out at the perforations, but is prevented from re-
turning by the back pressure on the elastic tube, which is pressed on to the
tubular portion and forms an air tight joint.
The ball bearings and bearing parts of the cheeks and the corresponding

page_text: flanges of the casing may be protected from dust by means of thin plates suitably
secured, as by brazing, over the slots in the cheeks, and of guards, which may be
made of vulcanite, ebonite, or other light material but are preferably made of
transparent celluloid. Two pairs of guards are provided, each consisting of a
guard secured to a cheek and another secured to the corresponding flange. The
outer guard of each pair extends around its cheek and has two flanges which
are arranged on opposite sides of the cheek and are perpendicular to the axis of
The
the hub and through one of which pass screws securing it to the cheek.
other guard is a disc fastened to the flange by means of screws bearing against
the inner flange of the guard just described and provided with a flange that
surrounds the last mentioned guard at a sufficient distance to allow of the move-
ment of the spindle within the hub; it will, however, be understood that the
The inner guard
outer guard may overlap the inner one instead of vice versa.
may also have a flange passing round and fitting the adjacent end of the casing
to keep the ball bearing free from dust; this flange may be dispensed with where
a chain driving wheel is secured on the end of a hub, as in that case the end of
the hub preferably extends considerably beyond the ball bearing and fits over a
correspondingly long boss on the flange of the casing.
For oiling the pins of the inner casing and the slots in which they work simple
holes, normally closed by plugs, may be provided in the cheeks at the upper
ends of the slots; or there may be screwed into each cheek at the same place an
oil cup having a removable cap.
Any suitable means may be provided for oiling the ball bearings. For ex-
ample, each end wall of the hub may have an oil hole in it and this hole may
be normally closed by a cover which may have a piece of soft rubber secured to
it to enter the oil hole and make a tight joint therewith and which is normally
pressed against the end wall of the hub by a spring, which may be secured at
one end to the wall by screws that also fasten the cover in place; or there may be
provided an internally screw threaded cylindrical oil cup which is provided with
a removable cap and in which fits an externally screw threaded and centrally
perforated piston or false bottom, from which extends a tubular stem that ex-
tends through the end of the cup remote from the cap and is screwed at its outer
end into a cross piece, which may be secured by means of a set screw and a small
plate to two of the spokes and from which one or two branch pipes may lead to
one or both of the ball bearings. With this device the oil is contained between
the piston and the cap and when it is desired to supply oil to the bearing or
bearings the cup is screwed round the piston so as to move the latter nearer to
the cap, whereby oil is forced through the perforation in the piston and along
the stem to the place required; again, there may be provided for each ball bear
ing a small tube arranged radially between the end wall of the hub and the end
wall of the inner casing, and secured to the cylindrical portion of the hub at its
outer end, where there may be attached to it a capped oil cup.
Improvements in Pneumatic Wheel-centres.
We, JOHN EVANS, of Cleveland House, Grange Town R.S.O., in the County of
York, Engineer, and ROBERT WILLIAM HEALEY, of 11, Middlesboro' Road, South

page_text: Bank, Yorkshire, Draughtsman, 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:-
This invention consists of improvements in pneumatic wheel centres and has
for object to impart to wheels provided with solid or cushion tyres all the advan-
tages that result from the use of pneumatic tyres, whilst insuring them against
the disadvantages, such as side slipping and punctures, attendant thereon.
Although the invention is specially designed for use in bicycles and tricycles, it
is also applicable to other vehicles.
A pneumatic wheel centre according to this invention comprises a hub to
which the spokes or their equivalents are secured and which has a large central
aperture at each end; a casing around which the hub is intended to rotate and
which has also a large aperture at each end through which passes a spindle,
which can fall and rise therein and which is secured, so as to be incapable of
rotation, to the frame of the vehicle and is provided with a bore extending for
a short distance from one of its ends and containing an air valve; means for
preventing the casing and hub from moving laterally on the spindle and for pre-
venting the casing from rotating unduly about the spindle; and a pneumatic
tube surrounding the spindle, supporting it within the casing, and connected
with the bore of the spindle so that when necessary it can be inflated through
the valve. Means may also be provided whereby the casing can be rigidly se-
cured to the axle if the pneumatic tube burst and no fresh tube be available.
Figs. 1 to 6 inclusive of the accompanying illustrative drawings represent the
centre of the front wheel of a rear-driving bicycle constructed according to this
invention: Fig. 1 being a longitudinal view thereof, principally in axial section
but partly in elevation; Fig. 2 a broken elevation of the left-hand end of the
wheel-centre, the valve and its plug and box-nut being removed; Fig. 3 half a
section corresponding to the line a band half a section corresponding to the
line of Fig. 1; Figs. 4 and 5 respectively partial longitudinal sections drawn
to a larger scale of the left-hand and right-hand ends of the wheel centre, an
inflator having been substituted for the plug shown in Fig. 1; and Fig. 6 a
partial elevation of the right-hand end of the wheel centre drawn to the same
scale as Figs. 4 and 5. Fig. 7 is a section of a hub of modified form. Figs. 8, 9,
and 10 represent the centre of the rear wheel of a rear-driving bicycle constructed
according to this invention; Fig. 8 being a longitudinal section thereof with
the pneumatic tube omitted, Fig. 9 a partial left-hand end elevation of the wheel
centre with the step removed, and Fig. 10 a partial right-hand elevation of the
wheel centre with the right-hand fork and mud-guard removed. Figs. 11 and 12
show respectively in longitudinal section and medial cross section modified forms
of the pneumatic tube and the spindle. Figs. 13, 14, and 15 show in medial
cross section other forms that may be given to the spindle. Figs. 16 to 21 inclu-
sive represent a connexion between the bore of the spindle and the pneumatic
tube, Fig. 16 being a longitudinal section, Figs. 17 and 18 partial front and rear
elevations thereof, Figs. 19 and 20 elevations taken at right angles to each other
of a part thereof, and Fig. 21 a perspective view of the hard or metal portion
thereof. Fig. 22 is a section illustrating another connexion between the bore
of the spindle and the pneumatic tube. Figs. 23 and 24 are respectively a sec-
tion and an elevation of a lubricating device. Figs. 25 and 26 are two sections
taken at right angles to each other of an alternative lubricating device. Fig. 27
) is a section illustrative of a third lubricating device. Figs. 28 to 31 inclusive
represent the centre of the front wheel of a rear driving bicycle with some of the
parts slightly modified; Fig. 28 being a longitudinal sectional view thereof;
Fig. 29 a side elevation of one of the side cheeks to be referred to; Fig. 30 a
section corresponding partly to the line e f of Fig. 28: and Fig. 31 a side view
5 of a detail. Figs. 32 and 33 illustrate the centre of the rear wheel of a rear-
driving bicycle showing modifications somewhat similar to those represented in
Figs. 28 to 30; Fig. 32 being a longitudinal section partly in elevation, and

page_text: Fig. 33 a left hand end view thereof with some of the parts removed and the
spindle in section
The hub may consist of two somewhat conical end pieces 1 (Figs. I and 8)
connected together by a cylindrical piece 2 and each having a central aperture 3
of large diameter around which is formed a race + for bearing balls 5.
Figs. 1 and 8 show the hub provided with flanges 6 for the attachment of
spokes 7, as is preferred, and Fig. 7 represents the hub adapted for radial
spokes 7, the end piece 1 being provided with cavities 8 for the reception of the
latter. The internal casing 9, which is preferably made of nickel-steel, may also
be cylindrical with conical end walls 10 terminating in cylindrical portions 11
having right and left handed screw-threads. The other portion of the bearing
for each set of balls 5 is formed by a flange 12 of suitable material, such as case-
hardened steel, which is screwed upon the corresponding portion 11 of the casing
and which has an outer plane surface 12ª perpendicular to the axis of the hub
and is provided with an outwardly projecting pin 13 (hereinafter referred to)
that may either be formed in one with the flange 12 (see Figs. 1 and 8) or be
screwed or riveted thereto as shown in Figs. 28 and 32 respectively; for further
safety in preventing the parts 11 and 12 from becoming unscrewed there may be
provided a fixing screw 11" as shown in Figs. 31 and 33.
The spindle 16 may either be approximately straight, as shown in Figs. 1
and 8, or be bent or cranked, as shown in Figs. 11 and 12, so that when the
spindle is in its highest possible position within the internal casing (see Figs. 11
and 12), the middle of the spindle, around which the air-tube 17 fits, will be
centrally within the casing 9. One end of the spindle may have a part 18 (Fig. 4)
made square in cross section and the other 19 (Fig. 5) be screw-threaded and have
fixed upon it a square nut 20, so that the spindle will be prevented from rotating
when these parts are fitted into the limbs 21 of the fork or corresponding portions
of the frame of the vehicle, which should be correspondingly formed.
On the part 18 of square section and the nut 20 of the spindle there may also
be fitted two cheeks 22 stamped or otherwise formed out of suitable material
such as case-hardened steel, each of which has a vertical plane surface 22ª per-
pendicular to the axis of the hub and adapted to fit close against the vertical
surface 12 of the corresponding flange 12, whose pin 13 engages in a vertical
slot 23 in the cheek 22. Although only one pin 13 is shown at each side, in some
cases another pin may be provided diametrically below and a corresponding slot
formed in the cheek 22, as indicated by dotted lines in Figs. 28, 29 and 31. The
slot in the lower part of the cheek should be wider than the diameter of the pin
that engages therein, in order that the hub may rock relatively to the frame
with the upper pins 13 as pivots, the lower pins and slots serving to limit the
rocking movement. The cheeks are suitably strengthened by means of ribs 22b
(Fig. 2), or sometimes the ribs may be dispensed with and the web gradually
thickened towards the centre as shown at 22 in Fig. 28. The cheeks 22 may be
limited as to inward movement by flanges 24 secured to (Fig. 5), or formed in
one with (Fig. 4), the spindle 16; these flanges may be received in recesses 24"
in the cheeks 22 and have their inner faces flush with the inner faces 22ª of the
cheeks; but in the case of the driving wheel of a bicycle it is preferred to form
the recess 24 for the flange 24 at the chain-wheel end of the spindle, in the
corresponding flange 12 of the casing 9 (Fig. 8) the boss of which is made speci-
ally long to accommodate the chain-wheel. In order to enable the distance
between the cheeks 22 to be adjusted, the flange 24 adjacent to the square nut 20
is preferably formed by a flanged nut (Fig. 5) or unflanged nut (Fig. 8) which
is preferably milled and is screwed upon the spindle before the square nut 20
is placed thereon. The cheeks 22 and the vehicle frame may be rigidly secured
on the spindle 16 by nuts 25, which force the cheeks 22 tightly against the
flanges 24 of the spindle.
The air or pneumatic tube 17 is preferably made of such a shape, when the
spindle 16 is practically straight (Figs. 1 and 8), that, when it is inflated, and,

page_text: the bicycle or other vehicle being not loaded, the spindle is in its highest possible
position within the casing, the lower part of the tube is of considerably larger
cross section than the upper part, as shown in Fig. 1; when, however, the
spindle 16 is bent or cranked as herein before described, the tube may be such
as to be, with the spindle in the position just referred to, of equal cross section
in its upper and lower parts, as shown in Figs. 11 and 12. The tube may be
constructed in any suitable manner; e.g., it may be a tube of rubber with an
outer casing of strong thin fabric, a tube of rubber with inner and outer casings
of fabric, a tube of fabric coated outside with rubber, a tube of fabric coated
inside and outside with rubber, or a tube of rubber with a separate outer cover
of fabric. The tube preferably fits tightly, as shown in Figs. 3, 12, and 30, on
the middle portion of the spindle, which is preferably of such a cross section as
to prevent the tube from creeping or slipping round it. For this purpose its
middle portion may be concavo-convex with the convex surface 16 either at the
top, as shown in Fig. 3, or at the bottom, as shown in Fig. 13, the edges being
suitably rounded; or its middle portion may, as shown in Fig. 14, have upper
and lower concave surfaces 16 and 16 and somewhat resemble in cross section
a double-headed railway-rail placed on its side, the portion 16d of the rear head
below the axis 16° of the spindle being somewhat larger than the upper por-
tion 16 and projecting somewhat rearwardly and the centre 16% of the section
being somewhat in front of the axis 16° of the spindle; again, the middle portion
of the spindle may, as shown in Fig. 15, be somewhat triangular in cross section,
having a front surface 16h approximately vertical, a lower surface 16 slightly
concave and slightly inclining upwards rearwardly, and an upper surface 16
with a considerable downward inclination and forming with the lower surface
a sharper edge than the two other edges; furthermore, and particularly when the
spindle is bent as hereinbefore described, the middle portion may as a whole (see
Fig. 12) be somewhat downwardly and forwardly inclined and its upper surface
may have a flat or convex front portion 16 and a concave or flat rear portion 16'
and its lower surface a flat or concave front portion 16" and a convex or flat rear
portion 16, the upper and lower surfaces being joined by rounded surfaces; or
the middle portion may, as shown in Figs. 30 and 33, be of approximately
uniform thickness with its front and back edges turned upwards and downwards
respectively, its cross section showing a long central portion disposed horizontally
below the axis of the ends of the spindle.
As an additional precaution against creeping, a sheath of suitable material,
such as steel, and adapted to fit the middle of the spindle tightly may be built
in, or secured to, the pneumatic tube.
The connexion between the interior of the pneumatic tube 17 and the bore 26
of the spindle 16 may be made in various ways.
According to one construction (see Figs. 1 and 11) there is secured in the tube
a short screw-threaded pipe 27 having on it two nuts 28 and 29, or a nut and a
dise, and an intermediate washer 30: the disc or corresponding nut 29 is rigidly
fixed on the end of the pipe 27 and is fixed permanently in position in the tube 17
whilst the tube is being made, the wall of the tube being clamped between it and
the washer 30 by the nut 28. The outer end of the pipe is enlarged and exter-
nally screw-threaded. Another pine 31, which may be flexible or not, is screwed
into or otherwise secured to the spindle 16: its outer end is provided with a
flange 32 and a box nut 33. which is screwed upon the enlarged end of the other
pipe 27 and produces a tight joint between it and the outer end of the pipe 31 by
means of an interposed piece 34 of suitable material such as vulcanized rubber
cr soft metal.
According to another construction (see Figs. 16 to 21) a flexible pipe 35. suit-
ably secured to the air-tube, terminates in a tubular and angular piece 36 of
suitable hard material such as metal, to which is pivoted at 37 a bridle-shaped
lever 38 and which has a reduced free end forming a shoulder 39. In the
spindle 16 there is secured a tubular piece 40, which has a hole 41 communi-

page_text: cating with its bore 42 and surrounded by a recess 43 and which has an outer
end surface 44 so curved that when the reduced outer end of the piece 36 is in-
serted into the hole 41 and the lever 38 is forced down along the curved sur-
tace 44, a rubber washer 45 placed on the outer end of the piece 36 will be
compressed by the shoulder 39 so as to form an air-tight joint. A notch 46 is
provided in the piece 40, in which a projection on the lever 38 engages when the
lever is moved into its extreme position shown in Figs. 16, 17 and 18. Instead
of being angular, as shown in Fig. 16, the piece 36 may be straight as in the
modified construction shown in Fig. 30.
According to another construction (see Fig. 22) a flexible pipe 47 permanently
secured at one end to the pneumatic tube 17 is secured at its other end over the
outer end of a nipple 48 secured in the spindle 16, the flexible pipe 47 being
wrapped with fine wire, twine, or other suitable material and thereby forced into
an annular groove 49 or annular grooves in the nipple. India rubber solution
may be used in making the joint air-tight.
The construction, as in all the examples shown, is preferably such that, when
desired, on deflating the air-tube 17 and removing the wheel centre from the
frame and the cheeks 22 from the spindle 16, the connexion between the bore 26
of the spindle and the air-tube 17 can be undone and the air-tube removed and
another one put into its place, through one of the end apertures 3 in the casing 9.
In the bicycle wheel centres shown by way of example, to undo the connexion
the valve end of the spindle is drawn back with the hub so as to allow the hand
to pass in through the corresponding opening 3.
In order to enable the cheeks 22 to be rigidly secured to the casing 9 so as to
render the wheel serviceable when the air-tube has burst and no duplicate is
available, each cheek may be provided with a set-screw 50 and the adjacent
flange 12 with a corresponding tapped hole 51, the parts of the flange surround-
ing the holes being preferably made thicker to provide a better hold for the
screws, as shown in Fig. 28. In order to prevent the screws 50 from entering
the holes 51 when not required, a washer 50* suitable thickness is placed upon
each of the said screws; these washers can be removed when it is desired to secure
the parts 9 and 22 together. When lower guide slots and pins are used, as here-
inbefore mentioned and indicated by dotted lines in Figs. 29 and 31, an exten-
sion 51 is formed on each flange 12 and provided with a tapped hole 51' in lieu
of the hole 51 and a corresponding tapped hole 51* is formed in the adjacent
cheek 22 to receive the set screw 50.
The valve employed in the spindle may be of any suitable kind. According
to one construction (see Figs. 1 and 4) it comprises a cylindrical body 52 that
fits loosely in a recess in the corresponding end of the spindle 16, is tapped out
to suit the screwed end of the nozzle 53 of an inflator, and contains a piece 54
of vulcanized rubber or soft metal such as lead, tin, or white composition metal,
shaped to allow the tapered end of the nozzle 53 to bed itself therein on being
screwed up and thereby to form an air-tight joint. A plug 55 may be normally
screwed into the hole intended for the nozzle 53 and be attached to the adjacent
cheek 22 by a chain 56. A milled box-nut 57 is screwed on the outer end of
the spindle 16 and presses it may be by means of an annular projection 58-
against the valve and thereby forces it into its place. A hole is made through
this nut to allow the nozzle 53 of the inflator to pass through. From the cylin-
drical body there extends a tubular portion 59 having near its outer end a flange 60
which fits in a portion of the bore of the spindle and between which and the
cylindrical body there is a rubber ring 61 which is forced, by the box nut 57,
against a shoulder 62 in the spindle, whereby an easily breakable air-tight joint
is produced. Over the inner and major part of the tubular portion 59 there is
stretched an elastic tube 63, which is closed at its inner end 64, there covering
the end of the bore of the projecting tubular portion 59 and is secured at its
outer end by strong fine twine, wire, or other suitable material wound round the
tube in a groove 65 formed between the flange 60 and an annular projection 66

page_text: formed on the projecting tubular portion. The elastic tube is perforated at 67
and 68 between its inner end and the annular projection 66 so that when air is
pumped into the valve it passes through the small hole at the inner end 64 of
the tubular portion 59, under the elastic covering (3 and out at the perforations
at 67 and 68, but is prevented from returning by the back-pressure on the elastic
tube, which is pressed on to the tubular portion and forms an air-tight joint.
The ball-bearings and bearing-parts of the cheeks 22 and the flanges 12 of the
casing 9 may be protected from dust by means of thin plates 69 (Figs. 1 and 8)
suitably secured, as by brazing, over the slots 23 in the cheeks, and of guards,
which may be made of suitable light material such as vulcanite or ebonite, but
are preferably made of transparent celluloid. Two pairs of guards are provided
in the example shown in Figs. 8, 9, and 10; each consisting of a guard 70 secured
to a cheek and another 71 secured to the corresponding flange 12. (The guards
are shown in section in Fig. 8 and indicated by chain-lines in Fig. 9). The
outer guard 70 of each pair extends around its check and has two flanges 70" and
70 which are arranged on opposite sides of the cheek and are perpendicular to
the axis of the hub and through the outer one of which pass set-screws 72 se-
curing it to the cheek. The other guard 71 is a disc, which is fastened to the
flange 12 by means of screws engaging in holes 71" in the flange, bears against
the inner flange 70% of the guard 70, and is provided with a flange 73 that sur-
rounds the guard 70 at a sufficient distance to allow of the free movement of the
spindle 16 within the hub; it will, however, be understood that the outer
guard 70 may overlap the inner one 71 instead of rice versa. The inner guard 71
may also have a flange 74 passing round and fitting the adjacent end 1 of the
hub to keep the ball-bearing free from dust: this flange may be dispensed with
where a chain driving wheel 75 is secured on the end of a hub (see right hand
portion of Fig. 8) as in that case the end of the hub preferably extends, as shown,
considerably beyond the ball-bearing and fits over a correspondingly long boss
on the flange 12 of the casing 9.
In the modified construction shown in Figs. 28 to 31 the part of the conical
end piece 1 that forms the race for the bearing balls is formed with a flange 4"
(Fig. 28) adapted to rotate concentrically within and close to another flange 12b
(Fig. 31) formed on the inner face of the flange 12 and thereby to form an effec-
tive dust-guard for the ball bearings. In the example of a driving wheel centre
shown in Fig. 32, the chain wheel 75 and the corresponding end 1 of the hub
are formed in one piece and from the former projects a flange 4 which extends
over a cylindrical portion of the boss of the corresponding flange 12.
Any suitable means may be provided for oiling the ball bearings. For ex-
ample, each end wall of the hub may have an oil-hole 76 (Figs. 1 and 23) in it
and this hole may be normally closed by a cover 77 (Figs. 23 and 24), which may
have a piece of soft rubber 77" secured to it to enter the oil-hole and make a
tight joint therewith and which is normally pressed against the end wall 1 of
the hub by a spring 78, which may be secured at one end to the wall by two
screws 79 that also fasten the cover in place; or there may be provided an in-
ternally screw-threaded cylindrical oil-cup 80 (Fig. 25), which is provided with
a removable cap 81 and in which fits an externally screw-threaded and centrally
perforated piston 82 from which extends a tubular stem 83 that issues through
the end of the cup remote from the cap 81 and is screwed at its outer end into a
cross piece 84 (see also Fig. 26) which may be secured by means of a set-screw 85
and a small plate 86 to two of the spokes 7" and from which one or two branch-
pipes 87 (two are shown) may lead to one or both of the ball-bearings. With
this device oil is contained between the piston 82 and the cap 81 and when it is
desired to supply oil to the bearing or bearings the cup 80 is screwed round the
piston 82 so as to move the latter nearer to the cap 81, whereby oil is forced
through the perforation in the piston 82 and along the stem 83 to the place
required: again, there may be provided for each ball bearing a small tube 88
(Figs. 27) arranged radially between the end wall 1 of the hub and the end

page_text: wall 10 of the internal casing, and secured to the cylindrical portion 2 of the hub
at its outer end, where there may be attached to it an oil-cup 89 having a
removable cap 89.
For oiling the pins 13 of the flanges 12 and the slots 23 in which they work,
simple holes, normally closed by plugs 90 (Figs. 1, 2, and 8) may be provided
in the cheeks 22 at the upper ends of the slots 23; or there may be screwed into
each cheek at the same place an oil-cup having a removable cap similar to that
shown in Fig. 27 and provided with an inwardly projecting tube like it.
It will be seen that in a wheel having a pneumatic centre according to this
invention the wheel's proportion of the weight of the vehicle will be borne by
the pneumatic tube 17, the lower portion of which will consequently be de-
pressed, allowing the ends of the spindle 16 to assume a more or less central
position within the apertures 3, and that should the wheel strike against a stone
or other obstacle, the hub and internal casing would swing backwards, with the
pins 133 as pivots, relatively to the frame of the vehicle and raise itself over the
obstruction the pneumatic tube being compressed in its forward portion and
allowing the frame to travel for ward with little hindrance until the obstruction
be passed, whereupon the hub and internal casing would swing forward, with
the pins 13 as pivots, into their normal position. The use of the pneumatic
annular tube 17 and the swinging connexion of the internal casing with the
frame by means of the slots 23 and the pins 13 thus presents a considerable ad-
vantage over pneumatic wheel centres in which the internal casing is allowed
only up and down movement in relation to the frame but no backward and
forward movement in relation thereto.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. A pneumatic wheel centre comprising a hub mounted to rotate freely upon
an internal casing in which a spindle rigidly secured to the frame of the vehicle
is supported within the said casing by an annular pneumatic tube surrounding
the spindle and prevented from rotating thereon and the casing is allowed both
an upward and downward and also a limited backward and forward movement
in relation to the spindle but is prevented from unduly rotating thereabout, sub-
stantially as herein before described.
2. A wheel centre of the kind referred to in the preceding claim, in which in
order to prevent the internal casing from unduly rotating about the spindle and
from moving laterally in relation thereto, the spindle is provided with fixed
cheeks 22 having slots 23 and the casing has flanges 12 with pins 13 that engage
in the said slots, substantially as described and shown.
3. A pneumatic wheel centre of the kind referred to in Claim 1, in which the
spindle is provided at one end with a non-return valve controlling a passage
within the spindle, between which passage and the pneumatic tube there is a con-
nexion capable of being readily undone, substantially as hereinbefore described.
4. In a pneumatic wheel centre of the kind referred to in Claim 2, means sub-
stantially as described whereby the internal casing can be rigidly secured to the
cheeks when required.
5. A pneumatic wheel centre of the kind referred to in Claim 1, in which the
pneumatic tube fits the spindle tightly and the latter is so formed as to prevent
the tube from creeping or slipping round it substantially as described and shown,
whether or not the pneumatic tube have built in it, or secured to it. a metallic
sheath that fits the spindle.
6. In a pneumatic wheel centre of the kind described, means for connecting
the bore of the spindle with the interior of the air tube constructed, arranged, and
operating substantially as described with reference to and shown in Figs. 16
to 21, or modified according to Fig. 30 of the accompanying drawings.
7. A pneumatic wheel centre of the kind referred to in Claim 2, in which dust

page_text: or mud guards are provided substantially as hereinbefore described with reference
to and shown in Figs. 8 and 9 of the accompanying drawings.
8. A pneumatic wheel centre constructed, arranged, and operating substan-
tially as hereinbefore described with reference to and shown in Figs. 1 to 6 in-
clusive; or modified according to Figs. 8, 9, and 10, or to Figs. 11 and 12, or to
Figs. 28 to 31 inclusive, or to Figs. 32 & 33, of the accompanying drawings.
For the Applicants,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.