An Improvement in or Applicable to the Driving Wheels of Locomotives.
Year: 1889

page_text: COMPLETE SPECIFICATION.
An Improvement in or Applicable to the Driving Wheels of
Locomotives.
I, THOMAS VERNON BELL, at present residing at Parkhurst's Private Hotel,
71, Euston Square, in the County of Middlesex, Doctor of Medicine, do hereby
declare the nature of this invention (a cominunication to me from abroad from
Charles Edwin Swinerton, of the City of New York, United States of America,
President of the Swinerton Locomotive Driving Wheel Company) and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
The present invention relates to locomotive driving wheels, and its object is to
produce a driving wheel having a certain improved feature of construction whereby its
efficiency and value are materially increased.
In the accompanying drawings, Fig. 1 represents in vertical section a portion of a
driving wheel embodying the present improvement; Fig. 2 being a corresponding
side elevation partly in vertical section. Fig. 3 is a view intended for comparison
with Fig. 1.
In the specification to Letters Patent of the United Kingdom granted to my
present correspondent and dated 28th April, 1887, No. 6214, is described and claimed
a driving wheel having a tread provided with plane facets, which collectively form a
polygon. According to the present improvement, the wheel, instead of being made
with plane facets, is made with concave facets; that is, facets which, in the plane of
the wheel axis, are concave in cross section. This method of construction is
represented at A in Fig. 1.
As is well known, the tread or upper surface of the rails now in ordinary use is or
a convex form substantially as represented in Figs. 1 and 3. It follows that by
forming the tread of the wheel with facets which, transversely to the tread, are concave,
the efficiency of the wheel as a driving wheel is increased. The distance from angle
to angle of the concave facets may be equal to the distance from angle to angle of the
plane facets described in the specification to the aforesaid prior Patent.
As will be seen by comparing Fig. 1. with Fig. 3,-the latter representing substan-
tially the extent of contact between an ordinary rail and a wheel constructed according
to the previous specification, whilst the former represents the increased extent of
contact between a similar rail and a wheel embodying the present improvement-the
new construction affords a material increase in the extent of the surfaces in contact.
While it is obvious that the concave facets, the subject of the present invention,
may be formed upon the tread of the wheel by any suitable mechanism, it is preferred
to employ for such purpose a rotary cutter, the blades of which have a convexity
substantially corresponding with the convexity of the rail-head. In this way, the
several facets of different wheels having the same degree of concavity may be
expeditiously produced. Such a cutter is, however, a well known implement in metal
working and is operated in the usual mauner.
Having now particularly described and ascertained the nature of this invention,
as communicated to me by my foreign correspondent, and in what manner the same is
to be performed, I claim :-
A locomotive driving wheel having a bearing face or tread composed of a series
of facets substantially as and for the purpose herein described, the bearing surface
of each facet being concave in section transverse to the tread.
Dated this 15th day of October 1889
G. G. M. HARDINGHAM,
Agent for the Applicant.