CERTAIN IMPROVEMENTS IN STEAM ENGINES
Year: 1823

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JACOB
PERKINS, late of Philadelphia, in the United States of America, but now of
Fleet Street, in the City of London, Engineer, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of His United Kingdon, bearing
date at Westminster, the Fifth day of June 1823, in the fourth year of His
reign, give and grant unto me, the said Jacob Perkins, my exors, adñiors,
and assigns, His especial licence, full power, solo privilege, and authority,
that I, the said Jacob Perkins, my exors, adññiors, and assigns, during the
term of years therein mentioned, should and lawfully might make use,
exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, and also in all our Colonies and Plantations abroad, the
Invention of "CERTAIN IMPROVEMENTS IN STEAM ENGINES," in my possession,
in consequence of communications made to me by a Foreigner residing
abroad, and discoveries by myself; in which said Letters Patent there is
contained a proviso, that if I, the said Jacob Perkins, shall not particularly
described and ascertain the nature of the said Invention, and in what manner
the same is to be performed, by an instrument in writing under my hand and
seal, and cause the same to be inrolled in His Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
Letters Patent, that then the said Letters Patent, and all liberties and
advantages whatsoever thereby granted, shall utterly cease, determine, and
become void, as in and by the same, relation being thereunto had, will more
fully and at large appear,

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Jacob Perkins, do hereby declare my said improvements to consist,―
First, of an improved rotary valve.
Second, of a new valve to serve as a throttle valve.
Third, of a new application of a loaded valve.
Fourth, of a new arrangement of rings for metallic stuffing.
Fifth, of a new condensing apparatus.
And that the nature of my said first improvement of an improved rotary
valve doth consist in reducing the friction caused by the action of the steam
on the upper surface of the revolving plate now in use in rotary valves by
substituting a revolving plug in lieu thereof, and opening the upper surface
of such plug to the atmosphere. It should here be stated, that when I say
the upper surface of the plate or plug, I suppose the valve to be in a horizontal
position. And that the nature of my second improvement of a new valve to
serve as a throttle valve, doth consist in opening and closing the passages for
the steam by means of the elasticity of a metalic plate acted upon indirectly
by the governor. And that the nature of my said third improvement, of a
new application of a loaded valve, doth consist in creating pressure upon the
steam generated for the purposes of the ongine, which pressure must be over-
come by such steam itself before such steam can act upon the piston or
reach the cylinder. And that the nature of my said fourth improvement, of
a new arrangement of rings for metallic stuffing, doth consist in keeping
the expanding opening of the flexible ring steam-tight by means of eccentric
and non-expanding rings. And that the nature of my said fifth improvement,
of a new condensing apparatus, doth consist in condensing the steam in the
eduction pipe as it leaves the cylinder by forcing the supply water, cold
or at a low temperature, round and along a considerable surface of the said
eduction pipe in such manner as to keep such supply water always under
pressure. And in further compliance with the said proviso, I, the said Jacob
Perkins, do hereby describe the manner in which my said several improve-
ments are to be performed, by the following descriptions thereof, reference
being had to the Drawings and Figures annexed, that is to say :-
As regards my said first improvement of a new rotary valve, it is described
by the Drawing marked A. Figure 1 is a plan of the main or fixed plate of a
rotary valve now in use, a representing the situation of the induction, and the
situation of the eduction pipe, and c, e, the channels leading in and out of the
cylinder. Figure 2 is a section of my improvement which I substitute for the
revolving plate now in use, and is, in fact, a revolving plug furnished with my
improved metalic stuffing, herein-after more particularly described. f, g, h, are

page_text: b
the three rings of the said metalic stuffing, and are kept up to the rim e, e, at
the top of the plug by means of the support ring c, c, which is acted upon
by the spiral springs shewn under it. d, d, d, d, are screws to fasten down
the collar c, e; a, b, are two channels for the steam, which, by the rotary
motion of the plug, are opened alternately to those openings shewn in Figure
1 at c and e. One of the principal properties of this plug is, that by its pecu-
liar construction, the steam which, in the revolving plate now in use, presses
wholly on the upper surface, and thus creates an increased friction accord-
ing to the force of the steam, is allowed in my improved valve to pass from the
induction pipe round the outside of the plug, filling the space J, J, Figure 4;
from this space it finds its way through the holes at r through the passage
into the passage C, and so into the cylinder. Having performed its duty in
the cylinder, the steam passes out of the cylinder by the passage e into the
passage d, and thence through the holes a, s, s, into the chamber G, whence
it escapes into the eduction pipe . Figure 6 is a plan of the under surface
of the said plug; a, b, are the two passages for the steam, and it will be
seen that the passage a communicates with the centre space or circular
chamber G by means of holes at s, s, s, and that the outside of the plug
communicates with the passage by means of holes at r, r, r. By this
arrangement it will be seen that the steam in the chamber a and the
chamber G will be pressing the plug upwards while the steam that is
suffered to enter into the space J, Figure 4, on its way into the passage b,
passes round the outside of the plug, but is still confined in the outer casing
of the plug, and will therefore press the plug downwards by acting on that
part of the plug immediately under the support ring c, c, in an equal
proportion, or nearly so, as the steam in the chamber G and passage a is
pressing it upwards, thus destroying, or rather neutralizing, the excess of
friction which would otherwise be created by an increase of force in the
steam. The plug receives its rotary movement through the medium of the
shaft P, which is furnished with a cogged wheel or other apparatus for that
purpose. Fig. 5 is a plan of Figure 3, and Figure 7 is a section of Figure 1,
and Figure 3 is a section of the outer casing of the plug or stuffing box
shewn by itself; and the outer casing or stuffing box being open at its upper
surface, it will be seen that the upper surface of the revolving plug, passing
through and above it, is of course open to the atmosphere, and subject therefore
to the pressure of atmospheric air only and not of steam, as is the case in the
upper surface of the revolving plate now in use in rotary valves.
And as regards my said second improvement of a new valve to serve as a
throttle valve, it is described by the Drawing marked B. Figure 1 is a section

page_text: of the side valve; d is a screw, acted upon by the governor, and working
in the screw plug h, h, the bottom of which plug, it will be observed, is
concave; b, b, is a thin flexible plate of steel or other metal, acted upon
by the end of the screw d, which action presses the steel plate so tightly
down upon the flat surface e, e, that no steam can escape from the passage a
while it remains in this position. When the action of this screw is removed
from the plate b, b, it rises from the flat position which it assumes in this
Figure up into the concavity at the bottom of the screw plug; a, 9, are
passages connected with the steam pipe, and f, f, is a circular communication
passage, by which the passage q is fed when the steel plate 6, 6, rises. By
this arrangement it will be seen that in the position which the steel plate
b, b, is represented in this Figure to assume, all cominunication is stopped
between the passages a and 7; but if the screw & were raised, the steel plate
b, b, would immediately rise by the under action of the steam, and a commu-
nication would be once formed between passes a and 7 by means of the
circular passage f, f. Figure 2 is a sectional plan of part of my said second
improvement, showing more clearing the relative situations of the passages
a, q, and f, f.
:
And as regards my my said third improvement, of a new application
of a loaded valve, it is described in the Drawing marked C. In this
Drawing, A represents a patent generator with its loaded valve V, and
B, B, the steam pipe communicating with such valve at one end, and
with the cylinder C at the other end. At D, in the steam pipe, is a
loaded valve, the nature of which is sufficiently explained by the Drawing,
except that it is necessary to state that the rod or plunger R. fits sufficiently
loosely in the tube T to allow of water rising round it in the tube to its
upper extremity, or nearly so. This water, being pressed upon by the steam
above it, will keep the leather or other collar at e, e, tight or close round
the lower extremity of the rod R, which is so long as to prevent the water
getting sufficiently heated to destroy the leather. It will be seen by this:
arrangement that the steam generated by the generator before it can pass
into the cylinder must force open the loaded valve at D by its own power,
and cause this pressure upon or interruption of the steam previous to its
entering the cylinder, being in fact the substance of my said third improvement.
It will be proper here to state the application of a loaded valve interposed a
between the steam chamber of an ordinary steam boiler and the cylinder,
will answer the same purpose. My said third improvement therefore does
not embrace any novelty that may be in the particular loaded valve described
in the said Drawing marked C.

page_text: And as far regards my said fourth improvement, of a new arrangement of rings
for a metalic stuffing, it is described by the Drawing marked D. Figure 1 is
an elevation of a piston, with my improved metalic stuffing, B being the flexible
expanding ring now used for metalic stuffing, and C, D, the two inflexible and
non-expanding rings which constitute my said fourth improvement. Figure 2
is a section of Figure 1, and Figures 3 and 4 are sections of the different
parts of the piston head shown separately. Figure 5 is a plan of the flexible
expanding ring now in use for metalic stuffing. By an examination of this
ring it will be seen that there is an opening at d, and to prevent the escape
of steam at this opening I place the two rings marked C, D, in Figure 1, one
on each side of the flexible ring. Figure 6 is a plan of one of the said
two rings, which will be sufficient to explain, as they are both alike. n is a
guide pin, on which the knotch cut in the ring at e moves loosely; c, c, are
two spiral springs, which press the side of the ring to which they are attached
reccentrically from the piston. When these two rings are fitted on the
piston, the part 7 should be arranged to come directly over the open part
d of the flexible expanding ring; and it will be seen by this arrangement
that when the piston is put into the cylinder these two eccentric rings C and D,
Figure 1, will press against that part of the cylinder immediately above and
below the opening in the elastic ring B, and will thereby supply the deficiency
occasioned in the piston by such opening in the clastic ring, and reversing
the action of the parts above described, the same may be equally well
applied as a stuffing for the piston rod.
And as regards my said fifth improvement, of a new condensing apparatus,
it is described in the Drawing marked E. In this Drawing A is a patent
generator or steam boiler, with its loaded valve; B, is an induction pipe
leading from the patent generator to C, which is supposed to be the cylinder;
D, is an eduction pipe, which passes through the tube T, and thence into a
reservoir or well R. This reservoir or well feeds the forcing pump P. The
pipe marked W is a pipe leading from the forcing pump into the tube T, and
the pipe marked Y, being a continuation of W and T, is the supply pipe to
feed the said patent generator. With this apparatus the operation of con-
densing is performed in the following manner (that is to say):-The steam
generated by the said patent generator passes by the induction pipe B into the
cylinder C at a very high temperature, and leaves the cylinder after having
performed its duties there at nearly the same temperature by the eduction
pipe D. While the steam is passing through that part of the pipe which
is encircled by the tube T, cold water from the reservoir or well R is puniped
through the tube in a contrary direction by means of the forcing pump P. The
effect of this operation will be, that the steam in the eduction pipe will be

page_text: condensed, and will run, in the form of water, into the well or reservoir R,
while the cold water, by passing through the tube T, becomes heated, and
in that state passes out of the tube T by the pipe Y, and thence into the
said patent generator.
Now whereas I do not claim to be intitled to exclusive privilege to any
such parts of machinery or apparatus as are described in my several de-
scriptions of the Drawings hereunto annexed to be now in use, nor to the
said generator and loaded valve therein described to be patent, but a rotary
valve so improved as aforesaid, and also a valve to serve as a throttle
valve on the principle aforesaid; and also my said new application of a
loaded valve, constituting an apparatus for the purpose of creating pressure
on the steam generated for the purposes of the engine, which pressure
must be overcome by such steam itself before such steam can act upon
the cylinder or reach the piston; and also an arrangement of rings for
metallic stuffing, on the principle aforesaid; and also a condensing apparatus
on the principle aforesaid, being every and each of them, to the best of
my knowledge and belief, entirely new, and never before used in these
Kingdoms, nor in any of His Majesty's Colonies or Plantations abroad, I do
hereby declare this to be my Specification of the same, and that I do verily
believe this, my said Specification, doth in all respects, fully and without reserve
or disguise, comply with the said proviso in the said in part recited Letters
Patent contained, and I do therefore hereby propose to maintain my exclusive
right and privilege to the same.
In witness whereof, I, the said Jacob Perkins, have hereunto set my
hand and seal, this Fifth day of December, in the year of our Lord
JACOB
(L.S.)
MAINS.
AND BE IT REMEMBERED, that on the Fifth day of December, in the
year of our Lord 1823, the aforesaid Jacob Perkins came before our said Lord
the King in His Chancery, and acknowledged the Specification aforesaid, and
all and every thing therein contained and specified, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute made for that purpose.
thousand