IMPROVEMENTS IN TRAMWAY LOCOMOTIVES
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Louis Constant Uhler and François
Frédéric Simonet at the Office of the Commissioners of Patents on the 31st
January 1880.
LOUIS CONSTANT UHLER and FRANÇOIS FRÉDÉRIC SIMONET, of Neuilly-sur-Seine,
in France. "IMPROVEMENTS IN TRAMWAY LOCOMOTIVES."
The locomotive, the subject of this Invention, is characterized by the following
appliances, which we claim as new :-
First. Application of superheated steam by means of a superheating apparatus
receiving the radiant heat of the furnace.
Second. A particular application of Wolff's principle, that is to say, four
cylinders, two of which release the steam into two larger cylinders of special and
extremely simple construction; the small cylinders are fixed directly to the large
ones, and overhang without necessitating the lengthening of the frame to support
them. The hermeticity between the two cylinders is obtained by a double hemp
packed piston (the axis of which is square with the axis of the rod of the pistons),
or by other packing, such as metallic spring band packing.
Third. Condensation of the steam by means of a tubular condenser acting by air
contact, in which condenser the vacuum is produced by air pump worked from one
of the axle trees of the locomotive. This condenser is of a particular construction,
in order to provide a large cooling surface (of from 880 to 1320 square feet) of
small weight, and taking up very little space.
The movement of the steam within the condensing tubes is obtained by means
of a case divided into two compartments, into one of which is received the
extremities of the cooling tubes, and the other the small pipes placed in the
interior of these tubes.
The steam on coming out of the cylinders passes through a purifier (before
entering the condenser) to cleanse it of oil and grease, in order that the con-
densation water may be used without inconvenience for feeding purposes.
Fourth. Application of driving straps for transmitting the power of the engine
to the axles, with the arrangement of all working parts at hand, and under the eye
of the driver, that is to say, out of the way of dust, water, and mud.
In short this new tramway locomotive transmits its force by straps, is worked by
superheated steam on Wolff's principle and with condenser.
The transmission of the force to the axles being made by straps there is no
shocks or vibration produced upon the engine, but if any only in but slight degree,

page_text: it is expended upon the fly wheels, which is as useful in these machines as well as
in all fixed machines. We apply also to our locomotives a speed regulator to
preserve a uniform speed, notwithstanding the irregularity of the gradients of the
road, and also to prevent any excess of the regulated speed; this regulator works a
valve connected to the small cylinder.
The principal advantages of this tramway locomotive are as follows:-
First. Absence of noise produced by escaping steam, or by the coupling cranks,
these two causes being entirely suppressed.
Second. Complete suppression of the water, being carried away by the escaping
steam, and by the suppression of forced draught.
Third. Regularity of working free from frequent accidents.
Fourth. No necessity of carrying a fresh supply of feed water, the same being
re-employed.
Fifth. The ability of producing the necessary power at a nominal pressure of
16 to 24 lbs. per square inch (instead of 40 to 60), on account of the employment
of straps permitting the machine to work at a convenient speed, whatever may be
the diameter of the wheels.
This enormous decrease in the pressure is on account of the means employed to
produce the steam in an economic and useful manner.