Improvements in Tramway Locomotives.
Year: 1896

page_text: Date of Application, 23rd June, 1896-Accepted, 25th July, 1896
COMPLETE SPECIFICATION.
Improvements in Tramway Locomotives..
I, ROBERT HARDIE, of Rome, Oneida County, in the State of New York, United
States of America, Mechanic, 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 the construction of tramway locomotives as I shall describe
referring to the accompanying drawings.
Fig. 1 is a plan of the motor truck, Fig. 2 is a cross section on the line x x of
Figs. 1 and 3, looking towards the right; and Fig. 3 is a side elevation:
a a¹ are the axles and wheels on which is mounted the truck frame, the lower
side-bars, 6' the upper side-bars, 62 uprights, and 68 cross-bars. The upper side-
bars 6 converge beyond the axles and are extended till they meet. The side
frames may be suitably braced and trussed to give the necessary rigidity.
The engine cylinders c are formed with bed-blocks c, each filling the space
between the upper and lower side-bars to which the cylinder with its bed block
is bolted thus serving to reinforce and bind the side-bars together. The valve-chest c²
projects inwards. Each piston rod c³ is connected to a cross-head c' which is guided
on the top bar 6 this having steel-liners c, on which the crosshead slides, its
bearing surfaces being tightened by keys c. The cross-head c is connected by a
rod to a pin c, on a rocker c¹0, which is journalled in a long bearing clon
the lower frame-bar b. Outside pins e on the rockers 10 are connected by rods c¹³
to side rods c, which connect crank-pins on the wheels a¹ the cranks on the
one side being at right angles to those on the other side.
Thus the engines are situated between the two axles and inside the wheels and
the motion is transmitted to the wheels without the use of a rotating crank-shaft,
or as it may be stated, inside cylinders are arranged with outside connections to
the wheels or drivers, the connecting rods receiving their motion from rockers and
taking hold of the side rods. The advantages of this arrangement, are that the
engines are placed at points most suitable for distribution of the weight and for
economy of space, while at the same time the stroke of the piston is long
relatively to the diameter of the wheels, the engines also are out of the way and
form parts of the truck frame. As the engines are inside the lines of the wheels
and near the level of the axles, the weight is distributed in such a manner as to
prevent swaying motion. The arrangement of the engines also allows the top bars
of the frame to be used as the guides for the cross-heads; and involves a comparatively
cheap and simple construction. The absence of a rotating crank-shaft, gives free
space for the accommodation of the air reservoirs, water-heater and other appliances
which are not shewn, but are intended to be carried on the truck, for supplying the
engines with compressed air, heated and charged with moisture, as motive fluid.
The main slide valve has its rod cle, and a cut-off valve on the back of the main valve
has its rod e¹7 both of which can be worked by any suitable gear from the rear axle.
This locomotive or motor truck, is especially designed for tramways or street
railways, compressed air being employed as the motive fluid, and a passenger
car-body being carried on the truck.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. The combination with front and rear wheels, of an engine arranged between the

page_text: axles and inside the wheel base, a side rod connecting cranks on the wheels, a rocker
receiving motion from a crosshead worked by the engine piston and a main rod
connecting the rocker to the side rod, substantially as and for the purposes set forth.
2. In combination with the wheels and axles, the pair of engines having their
cylinders forming parts of the sides of the frame, their cross-heads guided on the top
side bars of the frame the rockers co; the inside rods c connecting the rockers with
the cross-heads, the side rods c" connecting the cranks on the wheels and the main
rods connecting the rockers with the side rods, all substantially as and for the
purposes set forth.
Dated this 23rd day of June 1896
ABEL & IMRAY,
Agents for the Applicant.