IMPROVEMENTS IN THE COFREDUCTION OF STEAM BOLLERS AND THEIR APPLIANCER
Year: 1874

page_text: LETTERS PATENT to Francis Jackson, of Whinlatter, Keswick, in the
County of Cumberland, for the Invention of "IMPROVEMENTS IN THE
COFREDUCTION OF STEAM BOLLERS AND THEIR APPLIANCER"

page_text: As a further means of preventing too quick a rush of steam through
the pipe, into the steam dome, a valve is suspended in a cage below the
orifice of the pipe, and so arranged that so long as the steam passes
through at the ordinary rate it remains in the bottom of the cage, but
any undue speed of the steam would cause the valve to lift and close
the opening. The safety valve lever works on knife-edge centres
immersed in mercury, which prevents the steam from rusting them and
at the same time serves to lubricate them. The float is attached to a
lever, the fulcrum of which carries a quadrant on which rests a weighted
lever. When the float falls (owing to a deficiency of water) the other
end of this lever opens a small valve beneath, the weight on the safety
valve lever causing the weight to lift and open the safety valve, and
at the same time a quadrant attached to the lever raises a valve or
plug in the feed pipo orifice, and so stops the supply of water to the
boiler.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Francis Jackson in the Great Scal Patent Office
on the 16th October 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANCIS
JACKSON, of Whinlatter, Keswick, in the County of Cumberland, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of April, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto I, the said Francis Jackson, Her special license
that I, the said Francis Jackson, my executors, administrators, and
assigns, or such others as I, the said Francis Jackson, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF STEAM BOILERS AND THEIR APPLIANCES," upon the con-
dition (amongst others) that I, the said Francis Jackson, my exccutors

page_text: the boiler, the ends of the said tubes not meeting each other, but being
closed. Inside the fire space b, b, from end to end passes an inner
longitudinal water tube or space e, e, closed at the rear or chimney end,
but connected to the outer body of the boiler by a terminal water
space at the forward end of the boiler. If preferred this water
space e, e, may be reversed, that is, closed at the furnace end, and con-
nected to a terminal water space at the rear or chimney end. The front
section of the boiler forms a fire box, and in the lower portion (which
extends below the body of the boiler) the furnace bars 9, 9, are placed,
the fuel being supplied by an opening through the terminal water space.
The separate sections of the boiler are all connected to each other by
means of curved pipes h; h, those at the sides for the water and at the
top for the steam, and the water is applied (by preference) to the
section furthest from the furnace.
The steam dome i, i, is connected to the steam space of the boiler by
means of a pipe k, k, and is provided with an equilibrium valve 1, 1,
through which the steam passes out to the engine. This equilibrium
valve is connected to a small piston m, m, working in a cylinder n, n,
the upper part of which communicates direct with the steam space of
O the boiler by means of a small tube o, o, provided with a tap h.
If the engine commences to take steam too rapidly the pressure in the
steam dome i, i, diminishes, and that above the small piston m, m, being
the full pressure of the boiler forces down the piston and closes tho
valve 1, 1. As the valve 1, 1, closes the pressure of the steam in the
5 steam dome i, i, becomes equal to that above the small piston when the
latter is raised by the action of the weighted lever q, q, and reopen the
valve, and by these means the action of the engine is regulated without
any necessity for a governor." The number of revolutions per minute
which the engine shall be allowed to make before the valve closes is
Oregulated by opening or closing more or less the tap h, h, in the
tube o, o, leading to the small cylinder n, n.
As a further means of preventing too quick a rush of steam through
the pipe into the steam dome i, i, a valve r, 1, is suspended in a cage 8, 8,
below each orifice of the pipe k, k, and so arranged that so long as the
3 steam passes through at the ordinary rate it remains in the bottom of
the cage, but any undue speed of the steam would cause the valve to
lift and close the opening. There is also a similar valvo placed under

page_text: the openings of each of the curved pipes h, h, so that in the event of
the explosion of one section the steam from the other sections will not
escape; and thus injury by the scalding steam in case of an explosion
will be greatly lessened. The safety valve lever t, t, works on knife-
edge centres immersed in mercury, which prevents the steam from
rusting them and at the same time serves to lubricate them. The
float u, u, is attached to a lever v, v, the fulcrum of which carrics a
quadrant 10, 20, on which rests a weighted lever x, x. When the
float u, u, falls (owing to the deficiency of water) the other end of this
lever x, x, opens a small valve y, y, beneath, the weight on the safety
valve lever t, t, causing the weight to lift and open the safety valve z, z,
and at the same time an excentric 1, 1, attached to the lever x, x, raises
a valve or plug 3, 3, in the orifice of the feed pipe 4, 4, and so stops the
supply of water to the boiler.
Fig. 3 is a section showing the application of my Invention to a
vertical boiler. The sections of the boiler are connected together
at a, a, b, b, is the outer water space; c, c, the inner water space; and
d, d, the terminal water space; e, e, is the fire-box; f,f, the fire space
outside the water space c, c; and 9, 9, are tubes connecting the same
with the fire-box; h, h, are similar tubes leading from the fire space ƒ,f,
to the flue or chimney (see also Fig. 4, which is a section through the
line C, D, in Fig. 3); i, i, is the fire-door.
In order to prevent the accumulation of mud or sediment in the lower
part of the water space c, c, I make the bottom thereof dished or funnel-
shaped; and from the lowest central part thereof I have a tube k, k,
which descends through the fire-box e, e, and conveys all sediment into
a vessel 7, 1, below. There is also a pipe m, m, leading into this vessel
from the bottom of the outer water space b, b.
Fig. 5 shows a modification of my improved self-regulating throttle
valve differing but slightly from that shown in Fig. 1. In this arrange-
ment the equilibrium valves 1, 2, are attached to a lever j, j, the other
end of which carries a valve m, m, which is képt open by the weighted
lever q, q.
When the rush of steam to the engine becomes too great it
raises the valve m, m, and causes the lever j, j, to close the valves 1, 1;
but as soon as the equilibrium is restored the weighted lever q, q,
brings the valve m, m, into its original position and opens the
valves 1, 1.

page_text: Fig. O is a still simpler modification. The valves 1, 1, are attached to
a lever j, j, which is balanced by a pendulum weight m in such a way
as to hold the valves open to the desired extent, but when the rush of
steam to the engine increases the pressure on the valve A (which is
larger in area than the valve ), and the decreased pressure in the pipe k¹
causes them both to close, and as soon as the equilibrium is restored the
weight m opens the valves.
.
Fig. 7 is a modification of the improved safety valve which is
weighted by an interior weight 1. The longer arm of the valve lever t, t,
rests on the spindle of the valve y. The weighted lever v, v, is held up
by means of a catch x, x. u, u, is a hollow float attached to the end of
a lever w, w; as soon as this float falls, a tappet at the upper end of
the lever w, w, forces out the catch x, x, and allows the weighted end of
the lever v, v, to fall, and its other arm raises the valve y and closes the
plug 3 in the feed pipe 4. As soon as the valve y is opened, the steam
lifts the piston 5, 5, in the cylinder 6, 6, and causes the lever t, t, to
open the valve z, z. The steam passes out of the cylinder 6, 6, by the
openings 7, 7, and escaping by the pipe 8, 8, raises the weight 9, 9,
which closes the damper by means of a cord or chain 10 passing over a
pulley 11, the steam escaping through the pipe 12.
In another modification, shown at Fig. 8, is provided with two
weights, 1 and 2, the former being above the water and the latter
immersed in it to a certain depth. So long as the water line remains at
its normal level, the weight 1 being above the water, keeps the valve y
closed; but as soon as the water level recedes below the weight 2, that
weight being heavier and not supported by the water opens the valve y
and admitting steam under the piston 5, 5, opens the safety valve z; on
the other hand if the water rises so high as to reach and partly support
the weight 1, the other weight 2 then being the heavier causes the safety
valve to rise. It also blows off if the steam gets up to too high a
pressure. w is a blow-off tap, by opening which the engineer can at
any time admit stoam below the piston 5 and thus ascertain whether his
safety valve is in proper working order.
Having now described the nature and object of the said Invention,
together with the manner in which the same is to be or may be per-
formed or carried into practical effect, I wish it to be understood, that I
claim as my Invention;---