IMPROVEMENTS IN RAILWAY CAR WHEELS
Year: 1884

page_text: I SYDNEY PITT of Sutton in the County of Surrey Gentleman do hereby
declare the nature of my Invention for "IMPROVEMENTS IN RAILWAY CAR
WHEELS 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 that class of car wheels which I term composite, in
which the tire and body of the wheel are of different materials and has among its
objects to which I would draw attention in the beginning-
1. To securely attach the tire to the wheel-body in a convenient and inexpensive
manner, so that accidental lateral fractures of the tire in use will be less likely to
be disastrous.
2. To construct the wheel so that it will be to a proper extent elastic in use so
as to prevent the tire from becoming loose when heated and expanded by applying
the brakes, and to increase the durability of the wheel.
3. To provide for the expansion of the axle and hub, (in use occasioned by hot
journals,) without causing a dangerous strain on the wheel-body or tire.
4. To so construct the body and tire that the latter may be quickly and cheaply
attached, or removed and replaced by another tire.
These objects are well accomplished, for example in the particular form of my
Invention illustrated in Figs. 1 and 2 of the accompanying Drawings, to which
I will first exclusively refer-
Figure 1 being a diametrical section showing part of my improvements; and
Figure 2 a side elevation of the same, partly in section.
For the purpose of securely attaching the tire to the body of the wheel, the
tire is made with an internal flange or ring, which method of construction I am
aware is not broadly new, because such a ring has heretofore been made both
integral with the tire and also of a continuous single piece or hoop.
But when this internal ring is made integral with the tire its cost is greatly
increased on account of the difficulty of hammering or rolling to the required
shape.
Again, when it is made of a separate continuous attached piece, the difficulty and
cost of construction and union with the tire are very considerable and the result is not
Price 8d.1

page_text: satisfactory. Therefore I make my internal ring in curved sections and dovetail it
and key it into an annular dovetail groove in the inner face of the tire, which
I find is an improvement of great practical importance. But the section of the
ring and the annular groove is not strictly confined to the dovetail form, for it
may be of equivalent tongue and groove section as will appear further on.
In my improved wheel the only increased cost over a plain tire is for the
internal ring as a soparate structure, and for the dovetail or equivalent annular
groove in the tire in which it is held, and the very trifling cost of securing the
ring into the groove in the tire.
In point of safety the sectional ring is greatly superior to the solid ring or
flange, because steel tires almost invariably fracture laterally and the break is liable
to extend through the depending ring also if it be integral with the tire. With
the built up sectional ring this cannot occur and the fractured piece will be held
securely by its fitting the dovetail or equivalent formed ring.
The required elasticity and provision for expansion of the tire and also of the
axle and hub are obtained by the shape and material of the side plates or disks
which form the body of the wheel, and their mode of connection with the tire.
My improved wheel, as illustrated in Figs. 1 and 2, consists of a hub A,
preferably of wrought iron, having an annular projection B forming shoulders for
the reception of the side-plates C and D.
The hub may however be of malleable cast iron, or of steel or other metal. The
side plates are preferably of sheet iron of suitable thickness, or of steel.
The forms or contours of the side plates may be varied, but I prefer the forms
shown for this particular composite wheel. They are similar circular disks with
flanged rims, and, viewed from the exterior of the wheel, raised central portions,
substantially as illustrated.
E indicates the tire, which is preferably of steel, and has an annular dovetail
groove F in its inner face, from which projects inwardly a suitable distance a safety
ring G.
This ring is preferably of steel or wrought iron in sections or segments and
made to fit tightly into the dovetail groove of the tire. It is composed of two
sectional side pieces g with dovetail finish, as illustrated, so as to fit the dovetail
of the tire, and a sectional center piece or key g², which serves to hold them firmly
in place. In building up this ring in place in the tire the sections should be made
to break joints.
H indicates bolts or rivets passing through the side-plates and the ring, and I, I'
bolts or rivets passing through the side plates and the annular projection of the
hub.
The manner of manufacturing my improved car-wheel, as illustrated in Figs. 1
and 2, is as follows-
The hub and tire are formed by forging or casting in any usual manner, and the
dovetail groove in the inner face of the tire is turned or otherwise formed, and the
remaining portion of the inner surface of the tire is also made true by turning or
otherwise. The ring is then formed in the dovetail groove of the tire of suitable
pieces which have preferably been rolled to the required section and bent to the
required circle, the holes for the bolts being either punched or drilled.
The circular pieces forming the sides of the ring not having their ends welded,
or otherwise joined in the groove of the tire, but merely being in contact, may be
inserted in place by overlapping their ends sufficiently and then springing the
circular pieces into place in the dovetail groove in the tire. The central piece or
key is then afterwards put in in a similar manner, which forces the side pieces to
fit snugly in the dovetail portions of the groove. The ends of the key may be cut
tangentially if desired, or in the line of a suitable curve, so that the key may be
made to fill the entire space in the tire groove between the side-pieces, or the ring
may be put in in segments if desired. The foregoing is the simpler and the

page_text: preferred method of building up the ring within the groove of the tire, but there
are other methods.
The tangential lines in Fig. 2 indicate how in each set of sections forming one-
third of a ring there may be one piece cut tangentially at both ends, and the
adjoining pieces may be "correspondingly cut at one end to enable the ring to be
readily built up. Each plate or third of the ring may be composed of two or more
segmental pieces, as may be desired, and the ring may be built up in place in the
way suggested, or otherwise as preferred.
The hub having been properly bored and turned, or otherwise made true, and
the bolt holes drilled, the hub is next centered with the tire, and the side plates
having been formed of the proper size with bolt holes corresponding to those in
the ring and hub, they are forced by hydraulic pressure, or otherwise, into place so
as to bear, by their inner edges and outer bearing surfaces, firmly against the tire
and hub as illustrated, all the bolt holes being in coincidence. The flanged rims of
the plates form a more extended bearing surface for the tire than would their
edges alone, and, with the form of their central portion, give them, in connection
with the tire, the elasticity required in a car-wheel of the best type.
Side plates or disks of this construction may also be used to advantage where
the internal ring or depending flange is integral with the tire, but not with so
good effect in all respects.
Finally the plates are bolted to the ring and to the hub which completes the
wheel. The ring will hold all parts of the tire together in case of breaking or
cracking of the tire when the wheel is in use, and thus serious accidents that
sometimes happen from such causes will be averted.
Figures 3, 4, 5, 6, and 7 are diametrical sections of my improved composite
car-wheel, showing respectively slight modifications, all relating to mere elective
variations in the mode of connecting the wheel-body and the tire having a sectional
ring inserted centrally in the inner face of the tire.
For the purpose of securely attaching the tire to the body of the wheel it will
be seen from the Figures last referred to, to which exclusive reference will now be
made for a time, that the tire is formed with annular grooves or recesses in the
inner portion of its sides of dovetail, tongue and groove, or equivalent section.
The annular inward projection thus left constitutes the seat of the body of the
wheel, and in or about the center of its inner surface is an annular groove also of
dovetail, tongue and groove, or equivalent section, which contains the built up ring
of corresponding section.
I am aware that tires have been formed with annular grooves or recesses in their
sides for the purpose of securing them to the bodies of wheels, and I do not claim
them per se.
The body of the wheel is preferably formed in two parts, each with projections
corresponding in shape and dimensions to the grooves in the sides of the tire, and
when the parts forming the body of the wheel are secured together these projections
interlock with the annular inward tire projection, and like the inserted ring prevent
the tire from flying off in case of fracture.
Referring to the letters on Figs. 3, 4, 5, 6, and 7 of the Drawings it will be seen
that my improved wheel consists of the tire A, preferably of forged steel formed
with the annular inward projection B, having its sides of dovetail, or tongue and
groove outline, Figures 3 and 7 showing the dovetail, and Figures 4, 5, and 6
showing the tongue and groove form.
In or about the center of this annular inward projection of the tire is an annular
groove B¹ of dovetail section as shown in Figures 3, 4, 5, & 7, and of tongue and
groove section, as shown in Figure 6, these two forms, wherever they occur in the
construction of my wheel, being the same in substance and practical effect. Within
this groove B¹ the ring R is inserted.
C and D are disks, either of which may or may not have a portion or all of the
hub integral therewith. They are preferably of cast steel, but they may be of
wrought iron, or of malleable cast iron, or of the cast iron commonly used for car-

page_text: wheels. The forms of these disks may be varied, but I prefer the form shown.
Their flanged rims form a seat for the tire, and the return flanges of the rims form
annular projections or rings which enter the annular grooves in the edges of the
annular projection of the tire. The projecting rims may be strengthened if desired
by brackets E, F. Where the hub is separate from the disks a portion of the hub
extends radially outward a sufficient distance so that the bolts G may pass through
solid metal. In Fig. 5 I show the disks made in two parts, which is only a formal
modification.
H indicates bolts or rivets passing through the side plates and the ring K and
securing them together. In Fig. 7 I show annular projections P on the sides of
the ring R which enter into corresponding annular grooves in the disks and serve
to better connect the disks and ring.
The manner of manufacturing my improved car-wheel in the modified form just
described is as follows-
The tire is formed in any usual manner, as above stated, and its inner face and
the annular grooves are made true by turning or otherwise. The castings or
forgings forming the side plates are then bored and turned or otherwise made true,
and the holes for the bolts are drilled. The disks or side plates are then forced by
hydraulic pressure or otherwise into place in the tire, the inner portions of the
rims fitting the annular projections of the tire and the return flanges entering the
corresponding grooves in their sides. Finally the bolts G and H are put in place,.
which completes the wheel.
One side plate might be dispensed with and the annular web or ring bolted or
otherwise secured to a single plate, or a single side plate might be used combined
with one or two annular rings, or a tire having an annular web or ring integral
therewith might be used, combined with my improved side plates or with the
rings above named; although all these methods of construction are greatly inferior
in strength and security to my improved wheel, as above described.
Composite car-wheels are made with the wheel-body formed separately from the
tire, which is usually of steel, for the purpose of obtaining greater durability and
safety than is possible with the common cast wheel; but to obtain the durability
necessary to make wheels thus constructed ultimately cheaper than those of cast
iron, tires of a considerable degree of hardness, with a corresponding loss of
toughness, must be used.
As wheels are allowed to remain in use as long as it is considered their tires are
not liable to fracture, by miscalculation of their reduced strength after being worn
serious accidents have happened, and they have happened also through the tires
receiving unusual strains, or when the metal of which they were made possessed
less toughness than was expected, so that in order to insure safety with durability,
other means than the strength of the tire itself must be resorted to. For this
purpose a form of tire is used with my improved wheel, which holds in place the
main portions of a tire that may be fractured in use; thereby affording the greatest
possible safety, while permitting the use of metal of a fair degree of hardness, with
the durability resulting therefrom.
In the construction shown by the diametrical section, Fig. 8 of the Drawings,
two rings are inserted in the inner face of the tire, near its sides, thereby removing
the grooves with which they interlock to points where they do not reduce the
metal exposed to wear, with the additional advantage of supporting the sides of
the tire and reducing liability of circumferential fracture, as well as securing the
tire to the wheel-body by two annular webs or rings.
This method of construction further allows a more elastic tire seat than can be
obtained with any form of either single plate wheel, or of one having the
wheel-body formed of flat disks.
The still greater security gained by my arrangement of the rings on both sides
of the wheel-body, which also carries the annular grooves to points on the tire
.beyond the portion exposed to wear, is clearly shown by Fig. 8, as well as the

page_text: support given the tire when it is worn thin, by placing the rings in the position
shown.
A structure exposed to the excessive shocks and strains which a car-wheel
receives when carrying heavy loads, must possess a great margin of strength in
order that the elastic limit of the metal shall not be exceeded, so that while it is
desirable that a car-wheel shall be less rigid than the common cast wheel, it must
not be elastic to the extent of the axle and tire ever being sensibly other than
concentric. In my improved wheel the tire rests, as shown in Fig. 8, on the
flanged rims of the side plates, so that while their arched form gives a tire seat of
great strength, shocks are not communicated to the axle with the directness and
force that accompanies a rigid connection between rim and hub. While the flanges
forming the arch are directly over the rail, and thus bring it in the best position
to receive shocks, the side-plates are prevented from springing laterally by the
rivets passing through the plates and inserted rings of the tire, and holding the
edges of the flanges firmly in contact, forming in effect a continuous structure.
This construction further allows a tire having one inserted ring in place to be
put on the wheel-body or removed therefrom without removing the side-plates from
the hub.
Referring to the letters on the Drawing, Fig. 8, it will be seen that my improved
wheel consists of the tire A, having the sectional rings B, b, inserted in the annular
tire grooves C, c. The manner of forming and inserting the sectional rings is
already described.
D is the hub, which, with the side plates E, F, form the body of the wheel.
The side plates are secured to the hub by the rivets g, and the annular rings are
secured to the side-plates by the rivets h, which extend through the plates, and
hollow distance-pieces K. The distance-pieces, while supporting the side-plates,
allow their flanged rins to be drawn firmly together by the rivets, so that when
the wheel is completed, the tire is carried on what is practically a continuous
structure.
The manner of manufacturing my improved wheel, as shown in Fig. 8, is as
follows-
The hub may be, as in any other case, a forging or a casting of steel or strong
cast iron; the latter is the cheaper metal, and may be made amply strong.
The heavy forged band shown at M is added to prevent cracking the hub, should
the wheel be fitted too tightly on the axle.
The hub is bored for the axle and the outside and the sides of the annular
projection are turned, so as to insure the side plates fitting accurately, and the rivet
holes bored, all as in other cases.
The side plates are by preference formed of flanged steel plates, and as rolled
plates are of a uniform thickness, the completed wheel is balanced. They may
however, be made of steel castings, or of other suitable metal.
The rivet holes which coincide with those in the wheel hub are bored to insure
their being true, and the outside and edges of the flanged rims are made true by
turning or otherwise and the outer rivet holes formed; the distance from the edge
of the flanges to the inner face of the plates being made uniform. If suitable
appliances are used for flanging the plates, the outside of the flanges which form
the tire-seat can be made so nearly true that very little further finishing is
required.
The distance-pieces K, by preference, are short pieces of gas pipe or similar.
tube.
The tire is formed by casting, or forging, and rolling in any usual manner,
and its inner face with the annular grooves therein are made true by turning or
otherwise.
The inserted rings are by preference formed of rolled steel and are finished and
inserted in the manner already described.
In completing this form of my improved wheel after the different parts have
been finished as described, including the drilling of the rivet holes, the side plates
.

page_text: are first slightly heated, which expands the hole and allows them to be ensily
put in place on the hub, and one is first put on and allowed to cool in place.
Temporary pins are then put through the outer holes in this plate, on which are
placed the distance-pieces. The second side-plate is then put on the hub, the
temporary pins serving as guides to get the holes opposite, as well as retaining the
distance-pieces in place. The plates may now be riveted to the hub.
The tire with one of its inserted rings in place, is put on the wheel-body either
by hydraulic pressure or by heating it sufficiently, so as to allow it to be easily
put on, the temporary pins in the wheel-body forming guides to bring the holes
in the ring opposite those in the plates. The second ring is then inserted when
the outer row of rivets may be put in, each temporary pin being driven out as a
rivet is put in, so that the distance-pieces cannot get out of place. The hub-band
may be shrunk on either before or after the tire is put in place, which completes
the wheel.
A wheel thus constructed possesses every requisite for a first-class car-wheel.
Experience has shown that the greatest source of danger in the use of steel tired
wheels has been from broken tires, and however strong these may be at first, they
are continued in use until reduced in thickness so that they are no longer considered
safe. This point could of course soon be learned, were it possible to make metal
of uniform strength, but as unexpected defects are always possible, safety cannot
he secured by relying on the strength of a tire that is continually growing thinner.
Cast wheels, however made, are equally as liable to be imperfect, and where means
can be used to guard against unexpected defects, steel tires that have been properly
manufactured give the greatest mileage in proportion to their cost.
The body of my improved car-wheel, as shown in Fig. 8, is so constructed that
it forms a complete structure from which worn out tires can be removed and new
ones put on, so that a wheel capable of the same service as at first is obtained at
the cost of the tire only. The form of the wheel-body and the elastic material
of which it is made prevent vibration, and as the hub is turned true and the side
plates formed of sheets, each of a uniform thickness, the completed wheel is
perfectly balanced, a result practically impossible with wheels formed of cast
metal.
Experience has shown that cars cannot run smoothly with imperfectly balanced
wheels, and they are equally injurious to the track.
The metal wheel-body allows hot rivets to be used, which hold the different
portions without danger of their becoming loose, thereby avoiding the risk
inseparable from the use of bolts and nuts.
The first cost of my improved wheel-body is less than for the forged wheels
formed with radial arms joined by a continuous outer rim; it is more durable and
ultimately much cheaper; because the elasticity secured by its form and the metal
of which it is made prevent vibration and the crystallization shown by the
fractured arms of spoke wheels, even when these are made in the best manner.
The rigidness of the spoke wheels results also in greater shocks to the axle,
rendering them more liable to fracture, and when the tires are put on, they are
subjected to severe strains by the comparatively rigid spokes and rim; a result
so fully recognized that railways using this form of wheel are obliged to use
comparatively soft tires in order to obtain greater strength. The elasticity
resulting from my improved construction relieves the tire from this excessive
strain, and the inserted rings being made to fit securely in the dove-tails, (a result
cheaply secured by their construction,) they possess all the holding power required
to prevent the tire from being loosened by the brakes, while their power of
retaining fractured portions of a tire, by clamping its inner surface, allows harder
and much more durable tires to be used with greater safety than obtained by using
the softer tires with the present forms of wheels and retaining rings.
While the manner of constructing my improved wheel with two inserted rings in
its tire is the best for the purpose, as above described, it would be possible to
construct a wheel differing in some respects without departing from the spirit of

page_text: my Invention; such as constructing the wheel-body of plates in segments, whereby
some of the waste of metal resulting from cutting circular from square plates
would be avoided; or constructing the wheel-body of side-plates the flanges of
which did not quite abut against each other; or without flanges, the tire seat being
formed of an annular band or support, or reinforcement of the tire; or a wheel-
body of the same shape might be cast in one piece; or the arched plates might be
cast in one piece without the hub portion; or one of the tire rings might be formed
integral with the tire or separate but not inserted in the tire; or neither of the
outside tire rings might be inserted in the tire or separate from it so far as one
object of my Invention is concerned; but all would be formal and undesirable
modifications, and the wheel so constructed would be inferior to my improved
wheel when constructed in the best manner, but I do not limit myself to the exact
form of construction shown or described.
Having thus described my Invention, what I claim as new and desire to secure
by Letters Patent is―
1. The combination with a tire for a car-wheel having a dovetail annular groove
in its inner face, of a sectional dovetail ring secured in such groove, substantially as
set forth.
2. The combination with a hub of a car-wheel and its tire, provided with a
sectional dovetail ring, of side plates or disks pressed between the hub and tire and
bolted to the hub and ring, substantially as set forth.
3. In a car-wheel the combination with a hub and tire provided with a sectional
dovetail ring, of side plates or disks having flanged rims and bolted to the hub and
ring, substantially as set forth.
4. In a car-wheel, the combination with a hub, and a tire provided with an
internal sectional dovetail ring, of side plates or disks with rims curving outwardly
from the depending flange and bearing against the tire and bolted to the ring and
hub, substantially as set forth.
5. A tire for a car-wheel, having an inserted ring in its inner face, and grooves
or recesses of dovetail, tongue and groove, or equivalent sectional form in its sides,
substantially as set forth.
6. The combination with a tire for a car-wheel, having an inserted ring in its
inner surface, and grooves or recesses in its sides, of side plates or disks forming
the body of the wheel, substantially as set forth.
7. The combination with a tire for a car wheel having an inserted ring in its
inner surface, and grooves or recesses in its sides, of side-plates or disks with rims
curving outwardly and with return flanges interlocking with the grooves in the
sides of the tire, substantially as set forth.
8. In a composite cur-wheel, the combination with side-plates or disks having
flanged rims or rims curving outwardly, of brackets supporting said rims,
substantially as set forth.
9. The combination with a tire for a car-wheel having a ring inserted and secured
in its inner surface of side plates or disks recessed or grooved to interlock with
projections on the sides of the inserted ring, substantially as set forth.
10. In a car-wheel, the combination of the tire having annular grooves in its
sides, and the body of the wheel composed of one or more disks, the same being
flanged at the periphery for the purpose of forming a tire seat, of a ring or rings
on the wheel-body, and formed so as to interlock with the grooves in the sides of
the tire, substantially as set forth.
11. In a car-wheel, the combination of the tire having annular grooves in its
sides and an annular ring in its inner surface, with a wheel-body composed of one
or more disks, the same being flanged at the periphery for the purpose of forming
a tire seat, of a ring or rings on the wheel-body and formed so as to interlock with
the grooves in the sides of the tire, substantially as set forth.
12. In a car-wheel, the combination with the tire having an annular web or ring
in its inner surface and annular grooves in its sides of dovetail or tongue and groove
sectional form, of side plates or disks forming the body of the wheel with rims

page_text: curving outwardly from the annular web or ring and forming the tire seat, and
having return flanges interlocking with the annular grooves in the sides of the tire
and securing the tire to the wheel-body, substantially as set forth.
13. A car-wheel having its body-portion formed of plates with flanged rims, the
flanges being preferably in contact, so as to form a tire seat, or arch between the
side plates, substantially as set forth.
14. A car-wheel having its body portion formed of plates with flanged rims and
dish-shaped centers, the flanges being towards each other, and preferably in contact,
so as to form a continuous structure, substantially as set forth.
15. A car-wheel having its body portion formed of side-plates connected by an
exterior rim, which may be either a separate piece or solid with the plates, so as to
form a tire-seat or support between the side-plates, substantially as set forth.
16. The combination in a car-wheel of a tire having two annular rings on its
inner face; one or both of which are inserted and on the outside of the wheel-
body, with a wheel-body composed of side-plates connected by an exterior rim so
as to form a tire-seat between the side-plates, substantially as set forth.
17. The combination in a car-wheel of a tire having two annular rings on its
inner face, both being on the outside of the wheel-body, and a body portion formed
of dish-shaped side-plates connected by an exterior rim, or of dish-shaped side-
plates having their flanged rims in contact so as to form a continuous structure for
the tire-seat, substantially as set forth.
18. The combination in a car-wheel of a tire having one or more inserted annular
rings on its inner face, and a wheel body formed of side plates having flanged rims,
the Banges being preferably in contact, substantially as set forth.
19. The improvements in composite car-wheels herein described and illustrated
in the appended Drawings.