IMPROVEMENTS IN STEAM TRAPS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said James Gillies at the Office of
the Commissioners of Patents on the 29th March 1883.
JAMES GILLIES, of Glasgow, in the County of Lanark, " IMPROVEMENTS IN STEAM
TRAPS,"
This Invention relates to improvements in the arrangement or combination of
parts of steam traps for drawing off condensed steam or water from steam pipes
or vessels, and comprises also improvements in the construction of valvular details,
whereby the action of the trap or siphon is rendered extremely sensitive.
According to one modification; the improved steam trap consists of a close tank
or vessel of any convenient shape and size, into which is an inlet opening, commu-
nicating with the steam pipe or vessel from which the condensed steam or water is
to be drained, and provided with the usual. back pressure valve. Within this close
tank or vessel is fitted a
"float "
or light vessel, which may be of the same general
contour as the outer close tank, and of nearly the same size with merely sufficient
space between the two vessels to contain water for floating the inner vessel. In the
bottom of the outer tank of the trap is screwed or otherwise fitted an outlet tube
which passes up through the bottom of the float and extends up within it to a
considerable distance; and at or near the upper end of this tubular outlet is formed
or fitted a duplex valve, the seats of which are annular and are carried by a tube
attached to the float and fitting closely round the outlet tube. The valves are
enclosed by a dome extending down and attached to the valve tube, or to the
bottom of the float, and in the lower end of this dome, aperatures are formed for
the outlet of water from the inside of the float to and through the valves to the
outlet of the trap. Small apertures are also cut in the valve tube below the lower
of the two valve seats, and when the valves are open, the water entering by these
apertures in the tube, passes up through the lower valve, while the water has at
the same time free access through the upper valve from above.

page_text: An opening or openings are formed between the valves through which the
water passes to the inside of the outlet tube on which the valves are formed or
fitted.
When the trap is in use, the outer close vessel is full of water or condensed
steam, and the water overflows into the inside of the float which is open at the
top. The water accumulates in the float until the weight of the float, and of the
water within it balances the buoyancy or power of floatation of the float in the
water of the outer case. Until then the valve seats of the duplex valve which
are rigidly connected to the float, are kept up against the fixed valves; but when
the balancing point is passed, i,e, when the accumulation of water in the float
causes it to sink, the valve seats drop away from the fixed valves and allow the
water within the float to be forced by the pressure of steam within the trap,
through the aperpures in the dome and through the valves to the outlet which
discharges downwards. When part of the water within the float is forced out in
this way, the float is immediately buoyed up and the valves thereby closed; and
the valves remain so closed until further accumulation of water by condensation of
steam causes the float to sink again.
The two valve openings are made of the same area, or nearly the same area, so
that the pressure tending to open the one valve is counterbalanced by the pressure
tending to close the other; and a very slight extra accumulation of water in the
float, causes it to open the valves. The openings to the valve outlet are made at
same height within the float and the valve tube, so that there may be no tendency
to draw off the water altogether from the outer casing by siphonic or capillary
action through between the outlet tube.and the valve tube fitting over it.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Gillies in the Great Seal Patent Office on the 28th September
1883.
JAMES ĠILLIES, of Glasgow, in the County of Lanark
TRAPS
"
"IMPROVEMENTS IN STEAM
My said Invention relates to improvements in the arrangement or combination
of parts of steam traps for drawing off condensed steam or water from steam pipes
or vessels, and comprises also improvements in the construction of valvular details,
whereby the action of the trap or siphon is rendered extremely sensitive.
The Invention is illustrated by the accompanying drawings in which figure 1 is
a vertical section of a modification of the iniproved steam trap; and figure 2 is a
sectional elevation of the outlet valve arrangement.
*
The improved steam trap consists of a close tank or vessel A of any convenient
shape and size, into which is an inlet opening a communicating with the steam
pipe or vessel from which the condensed steam or water is to be drained, and
which may be provided with the usual back pressure valve. Within this close
tank or vessel A is fitted an open float or light vessel B, which may be of the same
general contour as the outer close tank and of nearly the same size with merely
sufficient space between the two vessels at b to contain water for floating the inner
vessel B. In the bottom of the outer tank A of the trap is screwed or otherwise
fitted an outlet tube C which passes up through the bottom of the float and
extends up within it to a considerable distance; and at or near the upper end of
this tubular outlet is formed or fitted a duplex valve c, c, the seats c', c, of which
are annular and are carried by a tube D attached to the float B, and fitting closely
round the outlet tube C which forms with the tube D a guide for the flo
The valves c, c, are enclosed by a dome E extending down and ttached by
screwing to the valve tube D, or to the bottom of the float B, and in the lower
end of this dome, apertures e, e, are formed for the outlet of water fm the inside
of the float B to and through the valves c, c, to the outlet C of thtrap. Small
apertures d, d, are also cut in the valve tube D below the lower the two valve
seats c', c¹, and when the valves are open, the water entering by these apertures in
the tube may pass up through the lower valve, c, while the water has at the same
time free access through the upper valve c from above.
An opening or openings c² are formed between the valves c, c, through which
the water passes to the inside of the outlet tube C on which the valves c, c, are
formed or fitted. The valve seat c¹, c', is formed in two pieces, so that it may be
fitted over the duplex valve.
When the trap is in use, the outer close vessel A. is full of water or condensed
steam, and the water overflows into the inside of the float B which is open at the
top. The water accumulates in the float B until the weight of the float and of
the water within it balances the buoyancy or power of floatation of the float B in
the water of the outer case A. Until then the valve seats c¹ c¹ of the duplex
valve, which are rigidly connected by the tube D to the float B, are kept up
against the fixed valves c, c,; but when the balancing point is passed i,e, when the
accumulation of water in the float B causes it to sink, the valve seats c', c', drop
away from the fixed valves c c, and allow the water within the float B to be
forced, by the pressure of steam within the trap, through the apertures e in the
dome E and in the tube D and through the valve openings c, c², to the outlet C,
which discharges downwards or through the outlet aperture C. When part of the
water within the float B is forced out in this way, the float is immediately buoyed

page_text: up and the valves c, c, thereby closed. The valves remain so closed until further
accumulation of water, by condensation of steam, causes the float B to sink again.
The two valve openings or seats c¹, c¹, are made of the same area or nearly the
same area, so that the pressure tending to open the one valve is counterbalanced
by the pressure tending to close the other, and a very slight extra accumulation of
water in the float B causes it to open the valves. The openings d and c² to the
outlet are made at some height within the float B and the valve tube C, so that
there may be no tendency to draw off the water altogether from the outer casing A
by siphonic or capillary action through between the outlet tube C and the valve
tube D fitting over it.
.
For the purpose of admitting air to the steam pipes to destroy the vacuum that
would be formed by condensation of the steam when the pipes are not in use, and
to permit of the escape of such air when the apparatus is again used, an air
valve F may be fitted in the top of the casing. A, and on its spindle fis fitted a
float or inverted cup G. When the apparatus is out of use, the weight of the
cup G draws down the valve from its seat, but when steam is admitted to the
pipes, the water lying in the pipes flows to the trap casing A, floats up the cup G
and closes the valve F against its seat. The pressure of the steam when it enters
the trap casing A. retains the valve in its closed position after the level of the
water is lowered to the normal point.
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 combination of parts forming the improved steam trap, substantially
as herein described and illustrated.
Second. In a steam trap, the combination of the duplex valve c, c, and valve
Beats c¹, c¹, actuated by a float B within the trap casing, substantially as herein
described and illustrated, and for the purpose set forth.
Third. In a steam trap, the arrangement in the water outlet, of a duplex valve
and valve seats, the pressure on which is balanced, or nearly balanced to render
the trap extremely sensitive, substantially as herein described and illustrated.
In Witness Whereof, I the said James Gillies, have hereunto set
hand
and seal, this Twenty Sixth day of September, in the year of our Lord, One
thousand eight hundred and eighty three.
my
THERA ALLTrna
Witness
WALLACE FAIRWEATHER. C.E.
Fel. Inst. Patent Agents
Glasgow.
JAME
ALLTrna