Improvements in Wheels for Velocipedes and other Vehicles.
Year: 1892

page_text: Date of Application, 3rd May, 1892
Complete Specification Left. 2nd Feb., 1893-Accepted, 4th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in Wheels for Velocipedes and other Vehicles.
I, JOHN MABRY MCMAHAN, of 15, Park Row, New York City, United States
of America, Electrical Engineer, do hereby declare the nature of this invention to
be as follows:-
:-
My invention relates to wheels for velocipedes, perambulators, cabs and other
vehicles, and is designed to provide improved means for diminishing the vibration
of such vehicles when travelling over rough or uneven roads.
In the Provisional Specification filed with my former application, No. 6813
dated 9th April 1892, I have described an invention which consists in providing
the wheels of vehicles with pneumatic hubs for the purpose of diminishing the
vibration of such vehicles.
According to one part of my present invention, I make a vehicle-wheel with a
pneumatic hub comprising any suitable number of hollow balls or spheres of
india-rubber filled with air either at atmospheric pressure or compressed to any
desired higher pressure. These balls or spheres together form a very efficient
pneumatic cushion, and are effectually protected against injury by the metal portions
of the hub.
In carrying my said invention into practice I find it advantageous to proceed as
follows, viz. I provide the hub proper, that is to say, the part that fits upon the
axle, with a flange or disc at each end thereof, one or both of such flanges being
removable. Between this hub and an annular piece or casing which I term an
idle hub and to which the spokes are attached in any convenient manner, I arrange
the india-rubber balls or, spheres, the aforesaid flanges or discs and the said idle
hub forming a box in which the said balls or spheres are enclosed, sufficient space
being left to permit the required lateral expansion of the said balls when
compressed.
I provide suitable means for ensuring the rotation of this idle hub with the
balls or spheres and with the hub proper, whilst permitting the said idle hub to
move relatively to the axle so as to compress the balls or spheres or permit the
reaction thereof as may be necessary. For this purpose I sometimes sink the
said balls or spheres into recesses or depressions in the exterior of the hub proper
and in the interior of the idle hub. And I find it advantageous to make each ball
or sphere with projections or lugs which extend into or through openings or cavities in
the idle hub and in the hub proper, and which may be secured in such openings
by means of split pins or in any other convenient manner.
•
In some instances I use a single circular series of my spherical cushions or
balls. In other instances, I employ two or more series of such balls or spheres ;
I thus obtain the advantages that a smaller idle hub can be used, and a larger
number of the said balls or spheres will be in compression when the hub proper is
moved radially relatively to the idle hub, than would be possible with a single
series of balls. When I use more than one series of balls or spheres, I prefer to
so arrange the same that the centres of the balls of one series are in line with
the points of contact of the balls or with the spaces between the balls of the
other series.
It may be advantageous to form grooves, recesses, or holes in the aforesaid
discs or flanges so as to afford additional space for the lateral expansion of the
balls when compressed.
If compressed air is to be used in the hollow balls or spheres, I provide each
ball or sphere with a suitable opening and valve to permit the introduction of
compressed air into the ball or sphere, and its retention therein, and I provide

page_text: suitable apertures through the idle hub to permit such introduction of compressed
air into the balls without the necessity for removing them from the hub.
I sometimes connect the balls with each other by tubes so that the air can be
forced through one into another, and so on throughout the entire series; in which
case, only a single opening provided with a valve is required for the introduction
of the air.
It is obvious that I can somewhat modify the construction of the improved
wheel without departing from the nature of my said invention. For instance I
can use other convenient means for connecting the balls or spheres with the metal
portions of the hub so as to prevent relative rotation of these parts.
My invention affords the great advantage that the hollow balls or spheres
containing the air are surrounded by the metal of the hub, and are, therefore, not
exposed to injury from the exterior. The idle hub can slide freely between the
aforesaid discs or flanges so as to bring the balls into action whenever a shock or
jar is imparted to the rim of the wheel, the said flanges serving as guides for the
said idle hub.
When no load is on the vehicle, the hub and idle hub are concentric or approxi-
mately so; with a load on the vehicle or when the wheel comes in contact with
an obstruction, the said hub and idle hub become excentric to each other and some
of the balls are compressed. The mere weight of a rider causes but a slight
amount of excentricity, and this excentricity continually varies when the machine
is travelling over rough roads.
If desired, I provide my improved wheel with an ordinary solid or other india-
rubber tire secured upon the wheel in any well-known manner.
Instead of using hollow spherical cushions or balls, I sometimes employ solid
india-rubber balls arranged as hereinbefore mentioned.
Dated the 3rd dow of Mar 1900
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Wheels for Velocipedes and other Vehicles.
I, JOHN MABRY MCMAHAN, of 15 Park Row, New York City, United States of
America, Electrical Engineer, 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 wheels for velocipedes, perambulators, cabs and other
vehicles, and is designed to provide improved means for diminishing the vibration
of such vehicles when travelling over rough or uneven roads.
In the Specification of former Letters Patent dated 9th April 1892, No. 6813,
I have described an invention which consists essentially in making a wheel for a
velocipede or other vehicle with a pneumatic hub, that is to say, with one or more
air-cushions suitably arranged between the axle or the hub and the spokes, for
the purpose of diminishing the vibration of the vehicle.
The pneumatic hub which I have more particularly described in my said former
Specification, consists of a single air-cushion of annular form arranged between
the hub proper and an idle or subsidiary hub to which the spokes are attached,
and which is fitted to slide towards and away from the axle between guiding discs,
flanges or the like attached to the hub proper, so as to alternately compress and
permit the reaction of the said cushion.
According to one part of my present invention, I make a vehicle-wheel with.a
pneumatic hub comprising one or more circular series of hollow balls or spheres of
india-rubber or similar material filled with air either at atmospheric pressure or
compressed to any desired higher pressure, and suitably arranged between the axle

page_text: or the hub' proper and the said idle or subsidiary hub. These balls or spheres
together form a very efficient pneumatic cushion, and are effectually protected
against injury from the exterior, by the metal of the said idle or subsidiary hub
and of the guides therefor.
My present invention, moreover, comprises other improvements hereinafter set forth.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a longitudinal central section showing part of a wheel with my present
improvements applied thereto.
Figure 2 is a side elevation of the same, some of the parts being removed.
Figure 3 is a sectional elevation showing the relative positions of the hub and
idle or subsidiary hub when the lowermost balls are compressed.
Figure 4 is a longitudinal central section, and
Figure 5 a side elevation, some of the parts being removed, showing another
form or modification of my invention.
Figure 6 is a front elevation, partly in longitudinal central section, showing
details of construction.
Figure 7 is a side elevation, some of the parts being removed, showing another
arrangement of my improved pneumatic hub.
of
Figure 8 is a front elevation,
Figure 9 a longitudinal central section,
Figure 10 a section on the line x, x Figure 8, illustrating a further modification
my said invention.
Figure 11 is a front elevation illustrating details of construction.
Figures 12 and 13 are diagrams showing two forms of cushions in which the
balls are connected so that they can be all inflated through a single inlet-tube.
Like letters indicate corresponding parts throughout the drawings.
A is the hub proper; B is the idle or subsidiary hub surrounding the same and
to which the spokes are secured. C, C are the guiding discs or flanges attached
to the said hub A, the disc C¹, or both of the said discs, being so arranged as to be
readily removable in case of need. E, E are the hollow india-rubber balls or
spheres which serve as the air-cushions. The discs or flauges C, C' are so arranged
as to permit the requisite lateral expansion of the said balls E when the latter are
compressed by the movement of the hub A towards the subsidiary hub B.
The weight of the rider is transmitted from the axle to the hub A and
through the balls E to the idle or subsidiary hub B and thence to the tire
through the spokes H, the lowermost balls of the series being compressed and
the hub A becoming eccentric with the subsidiary hub B. In the rotation of
the wheel, the balls E are thus compressed in succession. To permit the required
relative radial movement of the hub A and subsidiary hub B, the said subsidiary
hub is accurately fitted between the flanges or discs C, C¹ so that it can slide freely,
the said subsidiary hub being either made of sufficient thickness to form a suitable
guiding surface as shown in Figures 1, 2 and 3, or being provided with internal
flanges B¹ as shown in Figure 4 or in Figure 9.
When the wheel strikes an obstruction on the road, the lowermost balls of the
series will be still further compressed, and will subsequently react, so that no
heavy shock or jar will be communicated to the rider. In the arrangements shown
in Figures 1, 2 and 3, and in Figures 4, 5 and 6, the disc C is formed integrally
with the hub A and the disc C₁ is screwed upon the said hub and bears against a
shoulder A¹ thereon. In the arrangement shown in Figures 8 to 11, both of the
aid discs C, C₁ are screwed upon the hub A.
To prevent relative rotation of the hub A and subsidiary hub B, thereof, I
sometimes sink the balls E into recesses or depressions in the exterior of the hub A
and in the interior of the subsidiary hub B as shown in Figures 1, to 3. I find it
more advantageous, however, to form or fix on the hub A, driving arms or pro-
jections F, Figures 4, to 11 the shape of which may be varied according to the
size and number of the balls employed, and which may either be made of separate

page_text: pieces of sheet-metal, brazed or otherwise suitably secured to the outside of the
hub A, or may be formed integrally with the said hub; and to provide the
subsidiary hub B with similar driving arms or projections G.
In some instances, I use a single circular series of my spherical cushions or balls
as shown in Figures 4, 5 and 6, and in Figure 7. In other instances, I employ
more than one series of such balls or spheres as shown in Figures 1, 2, and 3 and
in Figures 9 and 10; 1 thus obtain the advantage that a smaller subsidiary hub
can be used with any given number of balls, and a larger number of the said balls
will be in compression when the hub A and subsidiary hub B are moved radially
relatively to each other. When I use more than one series of balls or spheres, I
prefer to so arrange the same that the centres of the balls of one series are in line
with the points of contact of the balls of the other series, or with the spaces
between these balls.
By arranging the balls as shown in Figure 7, I provide for enabling the
uppermost ball to turn about its axis in its seat, when the hub A becomes
eccentric with the subsidiary hub; this action takes place with each ball once
in each revolution of the wheel, and prevents a permanent set being given to
the balls.
I sometimes form grooves or recesses C², Figures 4 and 6, or suitable holes,
in the discs or flanges C, C¹, so as to afford additional space for the lateral
expansion of the balls when compressed by the movement of the hub A relatively
to the subsidiary hub B.
If compressed air is to be used in the said hollow balls, I sometimes provide each
ball with a suitable opening or inlet and valve to permit the introduction of com-
pressed air into the ball and to retain it therein, and I provide suitable apertures
through the subsidiary hub to permit such introduction of compressed air into
the balls without the necessity for removing them from the wheel. In such
case, however, I prefer to connect the balls with each other by tubes J as
shown in Figure 12 or in Figure 13 so that the air introduced through a single
inlet-tube E can be forced through one ball into another and so on throughout the
entire series.
My invention affords the great advantage that the hollow balls or spheres
containing the air are surrounded by the metal of the subsidiary hub B and
guides C, C, and are therefore not exposed to injury from the exterior.
When no load is on the vehicle, the hub A. and subsidiary hub are concentric
or approximately so as shown in Figures 1 and 2; with a load on the vehicle or
when the wheel comes in contact with an obstruction, the said hub and subsidiary
hub become eccentric to each other as shown in Figure 3 and some of the balls
are compressed. The mere weight of a rider causes but a slight amount of
eccentricity and this eccentricity continually varies when the machine is travelling
over rough roads.
It is obvious that I can somewhat modify the construction of the improved wheel
without departing from the nature of my said invention. For instance I can use
other convenient means for preventing relative rotation of the hub A and subsidiary
hub B.
If desired I provide my improved wheel with an ordinary solid or other
india-rubber tire or with a pneumatic tire, secured upon the wheel in any well-
known manner.
Instead of using hollow spherical cushions or balls, I sometimes employ solid
india-rubber balls arranged as hereinbefore described.
Having now particularly described and ascertained the nature of my Baid inven-
tion, and in what manner the same is to be performed I declare that what I
claim is
First. A pneumatic hub for a vehicle-wheel, comprising one or more series of
hollow elastic balls, substantially as hereinbefore described and for the purpose
ancsified

page_text: Second. A cushion for a pneumatic hub, comprising one or more series of hollow
balls connected in such a manner that they may be simultaneously inflated, substan-
tially as, and for the purposes, herein before described.
Third. The combination of the hub provided with the discs, flanges or other
guides, the idle or subsidiary hub arranged to slide between such guides towards
and away from the axle, and the elastic balls or spheres arranged between the
said hub and the idle or subsidiary hub, substantially as, and for the purposes,
hereinbefore described.
Fourth. A wheel provided with a pneumatic hub comprising one or more series
of india-rubber balls and so constructed that, when the lowermost balls are com-
pressed, the uppermost ball will be free to turn about its axis, substantially as
hereinbefore described.
Fifth. A wheel provided with my improved pneumatic hub constructed
substantially as described with reference to the accompanying drawings, for the
purposes specified.
Sixth. The modification of my invention wherein I employ solid masses or balls
of india rubber, substantially as herein before described.
Dated the 2nd day of February 1893
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.