IMPROVEMENTS IN SPEED GAUGES AND MILEAGE INDICATORS
Year: 1884

page_text: I WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co. Patent Agents
Southampton Buildings in the County of Middlesex do hereby declare the nature
of said Invention for "IMPROVEMENTS IN SPEED GAUGES AND MILEAGE
INDICATORS" and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This Invention relates to speed gauges and mileage indicators, and consists
partly in the peculiar construction and arrangement of the means employed for
equalizing the atmospheric pressure in the fluid tube of the speed gauge whereby a
more positive action of the fluid is obtained under the centrifugal force of an
archimedian screw; and partly in the peculiar construction, arrangement, and
combination of the various parts as more fully hereinafter set forth.
In the accompanying Drawing, the improved combined device is shown in
sectional elevation, the speed gauge and mileage indicator being adapted to be
driven by the same power.
A indicates the axle of the forward truck of a locomotive, which is provided
with a worm B, which drives a pinion C, properly journalled upon a shaft D, in
the casing E, secured to the truck.
Findicates a flexible shafting, one end of which is secured to one end of the
shaft D, while the opposite end is secured. to one end of the shaft I, properly
journalled in the head of a standard R, rising from the top of the vessel or
chamber G, which is designed to be located at any convenient point in the tender
of the locomotive. Within this vessel G is properly supported the vertical shaft L,
carrying an archimedian screw M, the upper end of which shaft projects through a
stuffing box S and carries a bevel pinion K which engages with a similar pinion J
upon the end of the shaft I.
Communicating with the interior of the vessel G, and near the bottom thereof, is
a tube O, and from the top of the vessel rises a syphon tube P, a glass tube T being
secured between the free ends of the tubes P and O, as shown, affording a
continuous passage or communication between the bottom and top of the vessel
and outside thereof. Back of the glass tube T is secured a speed board N
graduated into miles, similar to a thermometer. The vessel G is designed to be
filled, or nearly so, with glycerine or other suitable fluid.

page_text: The action of the screw M, when the locomotive is in motion, is to drive the oil
or fluid up the tubes O, T, while at the same time the air in the tube P is drawn
down or syphoned into the vessel, relieving the atmospheric pressure in advance of
the rising fluid, and allowing the latter to act positively under the action of the
the fluid rising or falling in the tube T according to the velocity of the
screw, indicating to the engineer the rate of speed at which his engine is being
driven.
screw,
V indicates a bevel gear wheel arranged to be driven by the pinion J upon the
shaft I, and connected with a train of gearing of the mileage indicator dial W,
which is provided with a mile hand, a ten-mile hand, a hundred-mile Land, and so
on, as may be desired. If the axle A makes 700 revolutions in a mile, the
archimedian screw is arranged to travel at the same rate, while the mile hand of
the mileage indicater is so geared that it will make one circuit of its dial during
the same time. By this arrangement of devices the engineer can at a glance see
how far he has travelled from a starting point, and at what rate per hour.
I am aware that various speed gauge and mileage indicators have been invented
and patented wherein a fluid is caused to rise in a tube under the centrifugal force
of a screw or flutter wheel, but in all these the tubes have been open or closed at
the top, and not provided with a continuous passage or communication between the
top and bottom of the fluid chamber; hence they have been very unsatisfactory in
their operation being compelled to overcome atmospheric pressure in one case, and
to compress the air in the other, the devices therefore being practically inoperative,
while with the improved construction these objections are obviated, in tha: the air
is syphoned out of the tubo in advance of the rising fluid, equalizing the
-atmospheric pressure within the vessel and tube, and allowing the fluid to rise and
fall positively and sensitively under the action of the screw.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is-
First. A speed gauge, consisting of a vessel G provided with an index tube T,
the ends of which are provided with tubes 0, P communicating respectively with
the bottom and top of the vessel G, within which an archimedian screw or other
suitable wheel is arranged to operate, substantially in the manner, and for the
purposes, de-cribed.
Second. In a speed gange the combination of the vessel G provided with a
proper screw or wheel M and a tube O carrying an index tube T, with the return
bend tube P affording communication between the upper end of the tube T and
the top of the vessel G, substantially as, and for the purposes, specified.
Third. A speed gauge and mileage indicator combined, wherein the latter is
driven from the gearing which gives motion to the speed gauge substantially as
described.
And
HASELTINE, LAKE & Co.,
For the Applicant.