Road Rollers, Tramcar and other Road Locomotive Engines.
Year: 1887

page_text: Date of Application, 7th Mar., 1887
Complete Left, 7th Dec., 1887
Complete Accepted, 13th Jan., 1888
111
Road Rollers, Tramcar
and other Road Locomotive Engines.
We, SYLVANUS EDDINGTON and JOHN EVAN STEEVENSON of New Street fron
Works, Chelmsford, in the County of Essex Engineers do hereby declare the nature
of this invention to be as follows:-
Our Invention relates to Traction Engines, tramcar, and other road locomotive
engines; and has for its object to enable springs to be interposed between the travelling
wheel axle on the one hand, and the driving gear and frame on the other hand, for the
purpose of neutralizing shocks in travelling over rough ground, the springs being so
applied and the construction of the parts being such that no relative change of position
can occur between the axes of the different gear wheels which would cause a variable
motion of the driving gear, or would cause the teeth of such wheels to mesh more or
less deeply as takes place when the springs are applied to the bearing of the travelling
wheel axle.
By our Invention, we obtain the effect obtained by the use of an elastic-tyred
travelling wheel which is expensive and heavy.
In carrying out our Invention, the main driving spur wheel is mounted to rotate on
a hollow trunnion fixed to the frame of the engine and through which the travelling
wheel axle passes with sufficient clearance to allow for the play of the axle consequent
on the roughness of the road. Between the rim of this spur wheel and the dise or
frame carrying the bevel pinions of the usual balance or compensating gear, or a
driving boss keyed on the main axle, we interpose series of springs which may be
applied to act either in tension or in compression (or both), said springs transmitting
the weight at this side of the engine, and also transmitting the rotary strain of the
driving gear. This pinion frame or disc is loose upon the travelling wheel axle and
alone transmits the weight thereto, the axle at this end not having any other bearing.
The compensating bevel gear wheels are fast on the axle and boss of the travelling
wheel respectively and gear with the compensating pinions mounted between them in
the aforesaid disc or frame in the usual manner.
Dated this 7th down of Mar 1987

page_text: COMPLETE SPECIFICATION.
An Improvement in Traction Engines and Road Rollers, Tramcar
and other Road Locomotive Engines.
WC SYLVANUS EDDINGTON and JoпN EVAN STEEVENSON of New Street. Iron
Works, Chelmsford in the County of Essex, Engineers, 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:-
Our invention relates to traction engines, tramcar engines, and other road locomotive
engines and has for its object to enable springs to be interposed between the axle of
the driving travelling wheels on the one hand and the driving gear and frame on the
other hand, for the purpose of neutralizing shocks to the gearing in travelling over
rough ground, the springs being so applied and the construction of the parts being
such that no relative change of position can occur between the axes of the different
gear wheels which would cause a variable motion of the driving gear or would cause
the teeth of such wheels to mesh more or less deeply, as takes place when the springs
are applied to the bearing of the travelling wheel axle.
Reference is to be had to the accompanying drawings forming part of this speci-
fication wherein the invention is illustrated as applied to a traction engine, the
application to a tramcar engine or road locomotive being similar and sufficiently
evident without special illustration.
Figure 1 is a transverse vertical section of a traction engine taken in the plane of
the driving wheel axle. Figure 2 is a horizontal section and figure 3 a sectional side
elevation, showing the bearings for the said axle. Figure 4 is a face view of part of
the balance gear wheel to which the springs are applied.
A A¹ are the driving travelling wheels and B their axle. The wheel A is connected
to the axle through the usual locking pin a engaging with a disc on the end of a sleeve
fast on the axle. The wheel A' is loose on the axle and is connected by a similar
locking pin a with the compensating bevel gear wheel which turns loose around
the boss of the disc or frame D. The other compensating bevel gear wheel C is fast
on the axle B which rotates in bearings in a sleeve E whereon the engine frame is
hung by straps and springs FF1 which latter permit free up and down play of the
axle with regard to the engine frame, as caused by inequalities of the road."
In order to admit of this movement of the axle at the driving gear end, the main
driving spur wheel G which is driven in the ordinary way, is mounted to rotate on a
hollow gudgeon a fixed to, and projecting from, the side of the engine frame and
through which the axle passes with sufficient clearance above and below to permit of
said up and down play, the bearing E being guided in this movement by vertical
slides formed in the gudgeon g in which it works as in a horn plate. Between the
rim of this spur wheel G and the disc or frame D carrying the bevel pinions c of the
usual balance or compensating gear CC we interpose series of spiral springs H which
alone transmit motion from the wheel G to the pinion disc or frame D so that all

page_text: driving strain must pass through them. The pinion frame or disc D is loose upon the
boss of the wheel A' and therefore partakes in the up and down motion of this end
of the axle B, this motion of the axle B and disc D independently of the wheel G
being permitted by the springs H. These springs which are spiral are approximately
tangential to the disc D that is to say, they are arranged between rims of the wheel G
and disc D in such positions at equal distances, entirely around the circle, as best to
transmit the driving strain. For this purpose, their opposite ends are respectively
pivoted to lugs on the periphery of disc D and lugs within the rim of the wheel G,
as shewn in figure 4. A second series of similar springs inclined in the opposite
direction may be used, the one set acting in compression and the other set in tension.
Instead of the dise D carrying the pinions of the compensating gear, it might be
simply keyed on the axle B to serve only as a connoction for the springs. In order to
prevent endwise movement of the axle B a pair of radius links I placed transversely
across the engine are pivoted by one end i to one side of the engine frame and by the
other end to a gudgeon on the bearing E at a point near the opposite side of the
engine, the pivotal centres of these links being horizontal, so as to permit free
independent motion of the axle in the vertical plane. In order to permit this motion
of the axle but prevent independent motion of the axle in the horizontal plane at the
end opposite to the driving gear, a radius link K is pivoted at k to the side of the
engine frame and has an eye at its free end embracing the bearing E, this radius link
lying in a fore and aft direction.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, we would observe that we are aware
that it has heretofore been proposed to interpose two springs between the driving
and driven wheels, as described in the specification of a patent granted to
H. and J. McLaren dated the 22nd day of July 1886 and numbered 9516, and we do
not therefore, claim broadly the interposition of springs; but we declare that what we
claim is
1. In a traction or other engine of the kind specified, the interposition between the
driving spur wheel and the axle or wheel to be driven, of springs arranged sub-
stantially as herein described in a circle entirely around the latter and forming the sole
connection whereby rotary motion is transmitted between the driving and the driven
wheel or axle, the driving wheel being mounted to rotate about the axis of the driven
wheel or axle in such manner that relative changes of position of their two axes is
permitted, substantially as herein specified.
2. In a traction or other engine of the kind specified, the combination of the circle
or series of springs arranged as herein described for transmitting the driving motion
of the driving spur wheel, with the balance or compensating gear, the parts being
arranged and applied substantially as herein described and illustrated in the drawings.
Dated this 7th day of December 1887