IMPROVEMENTS IN STEAM TRAPS
Year: 1884

page_text: I, JOHN AULD, of the city of Glasgow, in the county of Lanark, Engineer, do
hereby declare the nature of my said Invention for "IMPROVEMENTS IN STEAM
TRAPS," to be as follows:-
This Invention relates to improvements in the construction of steam traps.
The improved steam trap comprises a close vessel or casing to which the steam
pipe is connected and which has a discharge or outlet pipe fitted with a double
beat or other balanced valve. Within the close casing is fitted an open vessel or
"float" into which water of condensation is discharged from the steam pipe, and
this open vessel is suspended by a rod or link to a lever fitted with a counter
balancing weight, the balancing lever being either fitted outside or inside the trap
casing. When the balancing lever is fitted outside, the rod or link which connects
the inner vessel or float to the lever passes out through an opening in the top of
the casing. A tube extending from the top of the casing is fitted to surround the
rod and extends down into the water or the open vessel or float, so that the pressure
of steam entering the trap drives up the water to the top, but the steam itself
cannot escape. The discharge valve is in this case also fitted in the outlet tube
outside the casing, and is operated by a rod attached to the lever at the opposite
side of its oscillating centre. A stuffing box may be dispensed with at the opening
through which the valve rod enters the valve casing, and where the float rod passes
through the trap casing by fitting a washer and weight over the openings, any
leakage through the latter opening being carried off by a tube leading from a small
casing over the opening to the discharge pipe. When the balancing lever is fitted
within the trap casing the double beat outlet valve is also fitted within the casing
in an outlet near the bottom and is operated by the lever, or the balanced lever
may be carried through the casing into a close tube in which the valve rod may be
fitted. When the water of condensation overflows the inner open vessel it rises in
the trap casing and buoys up the inner vessel or float. The balancing lever is
thereby tilted, and its opposite end acting through the valve rod opens the balanced
valve, and allows a portion of the water to escape. When the water level is thus
lowered, the float falls again, and the valve rod being raised the outlet valve is
closed.

page_text: In this case in which the balancing lever is fitted outside the trap casing, the
weight of the "float" or inner vessel is balanced by a weight hung on the lever, or
by a spring. When the lever is fitted inside the casing, a rod on it may be carried
through the casing, and be acted on by adjustable weights or springs outside, or the
weights or spring may be fitted inside. Or a balancing weight and lever may be
dispensed with by forming the float or a part of it hollow, and maintaining it full
of air and free from water by fitting a flexible tube from the bottom to the outside
of the casing.
Dated this Twentyninth day of January 1884

page_text: I, JOHN AULD, of the city of Glasgow, in the county of Lanark Engineer,
do hereby declare the nature of my said Invention for " IMPROVEMENTS IN
STEAM TRAPS," 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 improvements in the construction of steam traps.
Several modifications of the improved steam trap are illustrated in vertical section
in figures 1, 2, 3 and 4 of the accompanying drawings.
The improved steam trap comprises a close vessel or casing A to which the steam
pipe B is connected and which has a discharge or outlet pipe C fitted with a double
beat or other balanced valve D. Within the close casing is fitted an open vessel or
float E into which water of condensation is discharged from the steam pipe B, and
this open vessel E is suspended by a rod or link F to a lever G fitted with a
counter balancing weight G¹, the balancing lever being either fitted outside the trap
casing, as in figure 1, or inside as in figure 2.
When the balancing lever G is fitted outside, the rod or link F which connects
the inner vessel or float E to the lever passes out through an opening in the top of
the casing.
A tube H extending from the top of the casing A is fitted to surround the rod F
and extends down into the water in the open vessel or float, so that the pressure of
steam entering the trap by the pipe B may drive up the water to the top, but the
steam itself cannot escape. The discharge valve D is in this case also fitted in the
outlet tube C outside the casing, and is operated by a rod I attached to the lever G
at the opposite side of its oscillating centre J. A stuffing box may be dispensed
with at the opening through which the valve rod I enters the valve casing K, and
where the float rod F passes through the trap casing, by fitting a washer and
weight over the openings, any leakage through the latter opening H being carried
off by a tube M leading from a small casing M¹ over the opening to the discharge
pipe C. When the balancing lever G is fitted within the trap casing the double
beat outlet valve D is also fitted within the casing K in an outlet C near the
bottom, and is operated by the lever G; or the balanced lever G may be carried
through the casing A into a close tube K¹ as in figure 2 in which the valve rod I
may be fitted. When the water of condensation overflows the inner open vessel E
it rises in the trap casing A and buoys up the inner vessel or float E. The
balancing lever G is thereby tilted, and its opposite end acting through the valve
rod I opens the balanced valve D and allows a portion of the water to escape.
When the water level is thus lowered, the float F falls again, and the valve rod I
being raised the outlet valve D is closed. In the case in which the balancing lever
is fitted outside the trap casing (as in figure 1) the weight of the "float" or inner
vessel E is balanced by a weight G₁ hung on the lever, or by a spring. When the
lever is fitted inside the casing, as in figure 2, a rod on it may be carried through
the casing A and be acted on by adjustable weights or springs outside, or the
weights or spring may be fitted inside as shown.
Figure 3 shows an arrangement in which the double beat valve D is operated by
the float E without the intervention of a lever. In this case the water of con-
densation falls within the casing A and outside the float E into which it overflows
and causes the float E to sink and open the valve D, whereupon the steam entering
the casing forces the water up the tube H and out through the valve D.
A balancing weight and lever may be dispensed with by forming the float E or
a part of it hollow, as in the example shown in vertical and horizontal section in

page_text: figures 4 and 5, and maintaining it full of air and free from water by fitting a
flexible discharge tube N from the bottom to the outside of the casing A. The
valve D which is attached to the float is in this case fitted directly over the outlet
opening C, and it may be a double beat or balanced valve.
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. The arrangement or combination of parts forming the improved steam
traps with double beat valves substantially as herein described and illustrated in
the drawings.
Second. A steam trap consisting essentially of a closed casing and a float
operating a lever connected to a balanced valve on the outlet, substantially as
berein described and illustrated in figures 1 and 2 of the drawings.
Third. In combination with the closed float F of a steam trap, the flexible pipe N
for drawing off water therefrom, substantially as herein described and illustrated
in figures 4 and 5 of the accompanying drawings.
Dated this Twenty seventh day of October 1884