IMPROVEMENTS IN LEVER AND EXPANSIVE METAL STEAM TRAPS
Year: 1881

page_text: LETTERS PATENT to Henry Lancaster, of Pendleton, near Manchester, in
the County of Lancaster, Engineer and Millwright, for an Invention of
"IMPROVEMENTS IN LEVER AND EXPANSIVE METAL STEAM TRAPS."
PROVISIONAL SPECIFICATION left by the said Henry Lancaster at the
Office of the Commissioners of Patents on the 5th January 1881.
HENRY LANCASTER, of Pendleton, near Manchester, in the County of Lancaster,
Engineer and Millwright. "IMPROVEMENTS IN LEVER AND EXPANSIVE METAL
STEAM TRAPS."
The object of this Invention is to construct lever and expansive metal steam
traps in a more economical, simple, and efficient manner than has hitherto been
attained. In each trap I use a comparatively short tube having at one end an inlet
box or chamber, and at the other end a valve placed in a valve box provided with
an outlet passage or nozzle, the tube being made of a metallic alloy capable of
expanding and contracting according to the temperature of the contents of the
tube, the alloy being composed of four parts of copper to one of tin, or thereabouts.
Instead of the equilibrium valve hitherto used in this class of steam traps, I use a
single surface valve corresponding with one seating, the valve surface and seating
having such an angle as to ensure a perfect closure, and thereby prevent leakage
and uncertainty of action, and for allowing the valve to be changed when required
it is held by a screw and nut to the valve spindle.
For enabling the valve to be worked by the expansion and contraction of the
metallic tube, I employ a double lever working on a fulcrum held in a bracket cast
to the valve box, the lever having a short arm connected to a rod held by an
adjusting screw and nut to the inlet box, and a longer arm with its end passed
through a slot in the valve spindle, the screw being of such a length that the valve
can be fully opened for blowing through as often as may be required. When the
tube expands by the heat of the steam in the tube, the valve is closed to prevent
. .

page_text: the steam from escaping; but when the tube contracts by the lessened temperature
of the tube arising from the water of the condensed steam, the valve opens to allow
the water and air to escape, and again closes when the tube expands by the heat,
and to prevent the tube from bending or being injured by accidental blows, and
also to keep up its temperature, I encase it in a metal casing of slightly lesser
length, so that the two can work together in a telescopic manner, and when desired
I employ a stay encircling both the exterior metal casing and the connecting rod to
prevent the rod from springing.
These improved steam traps allow the air and water from condensed steam to
escape from steam pipes without loss of steam, and are applicable to steam engines,
steam hammers, drying cylinders, steam presses, and to all descriptions of engines
and apparatus in which air and the water of condensed steam has to be discharged.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Lancaster in the Great Seal Patent Office on the 5th July
1881.
HENRY LANCASTER, of Pendleton, near Manchester, in the County of Lancaster,
Engineer and Millwright. "IMPROVEMENTS IN LEVER AND EXPANSIVE METAL
STEAM TRAPS.".
These lever and expansive metal steam traps are used in connection with drying
cylinders, slashing frames, steam pipes, steam presses, steam engines, steam hammers,
and all descriptions of engines and other apparatus in which air and the water of
condensed steam have to be discharged without loss of steam; and the object of
this Invention is to construct this description of steam traps in a more economical,
simple, and efficient manner than has hitherto been attained. In each trap I use a
comparatively short tube, having at one end an inlet box or chamber, and at the
other end a valve, placed in a valve box provided with an outlet passage or nozzle,
the tube being made of a metallic alloy capable of expanding and contracting
according to the temperature of the contents of the tube. Instead of the
equilibrium valve hitherto employed in this class of steam traps, I use a single
surface valve corresponding with one seating, the valve surface and seating having
such an angle as to ensure a perfect closure, and thereby prevent leakage and
uncertainty of action, and for allowing the valve to be changed when required, it is
held by a screw and nut to the valve spindle. On the accompanying Sheet of
Drawings Fig. 1 is a side view with part in section, Figs. 2 and 3 end views, and
Fig. 4 a plan of one of my improved lever and expansive metal steam traps drawn
to a reduced scale; and in the Figures a represents the valve box; b, the inlet
box; c, the valve; d, the valve spindle; e, the expanding and contracting tube; and
f, the discharge or outlet passage. For enabling the valve c to be worked by the
expansion and contraction of the metallic tube e, I employ a double lever g, h,
working on a pin or fulcrum i, held in a bracket / cast to the valve box, the short
arm h of the lever being connected to a rod held by an adjusting screw m and
nut in the bracket n cast to the inlet box, and the longer arm g having its end
passed through a slot in the top of the valve spindle, the screw m being of such a
length that the valve can be fully opened for blowing through as often as may be
required. When the tube expands by the heat of the steam in the tube, the valve
closes to prevent steam from escaping, but when the tube contracts by the lessened
temperature of the tube arising from the water of the condensed steam, the valve
opens to allow the water and air to escape and again closes when the tube expands
by the heat, and to prevent the tube from bending or being injured by accidental
blows, and also to keep up its temperature, I encase it in a metal casing o of
slightly lesser length, so that the two can work together in a telescopic manner;
and when desired I employ a stay encircling both the exterior metal casing and
the connecting rod / to prevent the rod from springing. In Figs. 1 and 4 the
expanding and contracting tube is made straight, but it may be formed of a spiral,
helical, or other coiled shape, in order to obtain great length in a comparatively
small space, and one example, enclosed in a metal case, is shewn in Fig. 5, and in
Fig. 6 I shew an inlet box having four openings or nozzles, one u to which the
tube e is connected, and one of the others for the inlet passage, and in this
arrangement the valve is capable of being adjusted, and the passages blown through
by means of the screw v and nuts w.
Having now described the nature and particulars of my said Invention, I desire
it to be understood that in lever and expansive metal steam traps I claim, the

page_text: single surface valve c, Fig. 1, and the mode of fastening and removing it by means
of a screw and nut, the bracket cast to the valve box, the screw m with its
hand-wheel for adjusting the valve and enabling the tube and passages to be blown
through, and the arrangement of the four nozzles shewn in Fig 6, combined with
the screw. and nut for enabling the valve to be adjusted and the passages blown
through.
In witness whereof, I, the said Henry Lancaster, have hereunto set my
hand and seal, this Fourth day of July, in the year of our Lord One
thousand eight hundred and eighty one.
Witness,
CHARLES W. COLLINS,
Manchester.
HENRY LANCASTER. (L.S.)