IMPROVEMENTS IN THE CONSTRUCTION OF ROTARY AND RECIPROCATING ENGINES
Year: 1878

page_text: LETTERS PATENT to James Eglinton Anderson Gwynne, of Essex Street Works,
Victoria Embankment, in the City of Westminster, and County of Middlesex,
Civil Engineer, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF ROTARY AND RECIPROCATING ENGINES."
Sealed the 12th November 1878, and dated the 15th August 1878.
PROVISIONAL SPECIFICATION left by the said James Eglinton Anderson
Gwynne at the Office of the Commissioners of Patents on the 15th August 1878.
JAMES EGLINTON ANDERSON GWYNNE, of Essex Street Works, Victoria Embank-
"IM-
ment, in the City of Westminster, and County of Middlesex, Civil Engineer.
PROVEMENTS IN THE CONSTRUCTION OF ROTARY AND RECIPROCATING ENGINES."
My Invention consists in the means of securing greater steadiness in the flow of
gas or other fluids to and from the machine or machines now used to exhaust or
force them, and preventing the oscillation in the pressure which the very best form
of mechanical exhausters now in use produces.
Referring to the Specification of Letters Patent granted to me and Benjamin Beal,
and dated the Twentieth December, One thousand eight hundred and seventy-one,
No. 3449, and to the machines therein described, I find that even when I fix two
of the rotary engines there described at right angles to each other, so that one is in
full action when the other is nearly out of action, considerable inequality in the
pressure of the gas being pumped or exhausted still exists; and the object of my
present Invention is to remove this inequality in the pressure, and to secure a
steady flow of the gases to or from the exhausting or forcing machines. This I
effect in several ways.
As the inequality in the pressure or vacuum is caused by the unequal quantity
of gas or other fluid passed through the machine or machines at various points of
their revolutions, I secure steadiness and equality in the pressure by introducing,―
First. A revolving cock or by-pass driven from the shaft of pumping machine,
which permits during its rotation of the escape from the rotating or pumping or

page_text: exhausting cylinder, of a quantity of gas or other fluid sufficient to equalize the
pressure at various points of the revolution, the gas or fluid which the revolving
cock or by-pass permits to leave the cylinder of the machine finds its way into the
suction main from which the gas is being removed, and no portion escapes. The
revolving cock or by-pass I construct so that the area of the openings or outlets
is quickly regulated and varied as desired.
Second. equalize the pressure by cutting holes of the required area in the slides of
the exhausting or pumping machine, which holes come into action only at certain
points in the revolutions of the exhauster, constructed as described in the Specifi-
cation of Letters Patent, No. 3449, of 1871; these openings permit a fixed quantity
of gas or other fluid to pass back to the non-pressure side of the exhauster, and thus
equalize the inequality of the pressure in the cylinder, and therefore in the mains.
Third. I secure equality in the pressure by pumping a quantity of gas from the
suction main into the discharge main, or from the suction into the pressure side of
the exhauster at the moment in the proportion of the inequality produced, and
I thus secure steadiness in the pressure and vacuum.
Fourth. I secure steadiness in the pressure by the use of a metallic or other disc or
piston connected with both suction and discharge side of the exhausting machinery;
by moving the dise or piston up- or down at the required moment the pressure is
relieved or increased as required on either side of the exhausting or pumping
cylinder, and the inequality of pressure in the gas or fluid being pumped or forced
is removed.
Fifth. I obtain equality by having an opening communicating with the suction and
discharge sides of the cylinder or cylinders, such opening or openings being regu-.
lated by a piston or slide which may be driven by an eccentric or otherwise from
the cylinder shaft, or the piston or slide may be stationary, and the openings may
be regulated as desired.
And, Sixth. By introducing a groove or opening in the side of the cylinder,
graduated as required, the admission of gas from one side to the other of the ex-.
hauster can be obtained.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said James Eglinton Anderson Gwynne in the Great Seal Patent Office on the
11th February 1879.
JAMES EGLINTON ANDERSON GWYNNE, of Essex Street Works, Victoria Embank-
ment, in the City of Westminster, and County of Middlesex, Civil Engineer. "IM-
PROVEMENTS IN THE CONSTRUCTION OF ROTARY AND RECIPROCATING ENGINES."
The said Invention relates to certain means of preventing oscillation in mechanical
exhausters or other rotary or reciprocating machines, for the purpose of securing a
steady and even flow of gas or other fluid.
The Invention consists in certain peculiar arrangements by which the surplus gas
or other fluid is allowed to slip or flow back at the desired point and moment, or
the necessary quantity may be forced forward as desired. These results are effected
in several ways.
My Invention consists in the means of securing greater steadiness in the flow of
gas or other fluids to and froin the machine or machines now used to exhaust or
force them, and preventing the oscillation in the pressure, and consequent variation
in the pressure or vacuum gauges, which the very best form of mechanical exhausters
now in use produces.
Referring to the Specification of Letters Patent granted to ine and Benjamin
Beal, and dated the 20th day of December 1871 (No. 3449), and to the machines
therein described, I find that when I fix two of the rotary engines described at
right angles to each other, so that one is in full action when the other is nearly out
of action, considerable inequality in the pressure of the gas being pumped or
exhausted still exists, and the object of my present Invention is to remove this
inequality in the pressure and vacuum, and to secure a steady flow of the gases to
or from the exhausting or forcing machines. This I effect in several ways.
As the inequality in the pressure or vacuum is caused by the unequal quantity of
gas or other fluid passed through the machine or machines at various points of their
revolutions, I secure steadiness and equality in the pressure by introducing,-
First. A revolving cock or by-pass (driven from the shaft of exhausting or
pumping machine, which permits during its rotation of the escape from the rotating
or pumping or exhausting cylinder of a quantity of gas or other fluid sufficient to
equalize the pressure at various points of the revolution; the gas or fluid which the
revolving cock or by-pass permits to leave the cylinder on the pressure side of the
machine finds its way into the suction main, from which the gas is being removed.
or exhausted, and no portion of the gas or other fluid escapes. The revolving cock
or by-pass I construct so that the area of the openings or outlets is quickly regulated
and varied as may be desired.
Second. I equalize the pressure or vacuum by cutting holes of the required area
in the slides of the exhausting or pumping machine, which holes can come into
action,only at certain points in the revolutions of the exhausters, which may be
constructed as described in the Specification of Letters Patent, No. 3449 of 1871,
before referred to; these holes or openings allow a fixed quantity of gas or other fluid
to pass back to the non-pressure side of the exhauster, and thus equalize the
inequalities of the pressure in the cylinder, and therefore in the exhausting and
pressure side of the mains.
:
Third. I secure equality in the pressure by pumping or forcing a quantity of gas
or other fluid from the suction or exhausting main into the discharge or pressure
main, or from the suction into the pressure side of the exhauster, at the moment and
in the proportion the inequality is produced, and I thus secure steadiness in the
pressure and vacuum.
--
:
Fourth. I secure steadiness in the pressure by the use of a metallic or other disc
or-piston connected with both the suction and discharge sides of the exhausting
machinery; by moving the disc or piston up or down at the required moment the

page_text: pressure is relieved or increased as required on either side of the exhausting or
pumping cylinder or cylinders, and the inequality of pressure in the gas or fluid
being pumped or forced is removed or equalized.
Fifth. I obtain equality by having an opening communicating with the suction
and discharge sides of the cylinder or cylinders, such opening or openings being
regulated by a piston or slide, which may be driven by an eccentric or otherwise
from the cylinder shaft, or the piston or slide may be stationary, and the openings
may be regulated as desired.
And, Sixth. By introducing a groove or opening in the side or segment of the
cylinder, graduated as may be required, and by which the admission of gas or other
fluid from one side to the other of the exhauster or exhausters can be obtained."
>
And in order that the said Invention may be more easily understood I more par-
ticularly describe the principal methods by which I may accomplish the same, and
for that purpose I shall refer to the several Figures on the Sheet of Drawings
hereunto annexed; the same letters of reference indicate corresponding parts
throughout.
. Figures 1, 2, and 3 of annexed Sheet represents the revolving by-pass or cock
which may be attached to the exhauster or exhausters, or reciprocating or rotary
pumps, for the purpose of preventing oscillation.
Figure 1 is a longitudinal section.
Figure 2, a cross section through X¹, X².
And Figure 3, a cross section through Z¹, Z²
It will be seen the by-pass consists of an outer cylinder or case E connected by
means of the pipes F and G cast with same, which pipes are connected to the inlet
and outlet pipes of the exhauster; inside this cylinder slides backward and for-
ward (not rotating) an inner cylinder B, the motion being actuated by hand wheel
and screw I. Within this cylinder B is the revolving cylinder J, with its proper
ports or openings..
It will be seen that when the exhauster is started the necessary quantity of gas
which is required to slip or flow back so as to prevent oscillation immediately
passes through the ports K from the outlet to the inlet side, and this quantity
increases exactly as is required until the blades of the exhauster have arrived at
about of their revolution, when the greatest amount of gas or other fluid has to
pass back, then the ports or openings in the by-pass commence to close in the ratio
required, and so the pressure on the suction and delivery main is kept at an even
guage. Should it be necessary to vary the pressure against which the exhauster is
working, the dimension of the ports in the revolving by-pass must also be varied
in a relative proportion, and this I accomplish by moving the cylinder B so as to
open or close the ports the required distance.
To enable this arrangement to be more easily understood I shew a complete view
at Figures 4 and 5 of the engine, with exhauster and revolving by-pass and pipes,
arranged in working order, in which A' and A2 are the exhausters and B¹ the
revolving cock; C is the connecting pipes.
Figure 6 and 6a shews my Invention when applied to exhausters not requiring
variation in the openings' area, and which is one of the simplest arrangements by
which my objects can be secured. Z is the cylinder of the exhauster; Y, the drum;
X, the slides, and in these slides I cut the openings or holes W, W, of the required
size and shape for passing the necessary quantity of gas, and thus equalizing the
pressure.
Figure 7 is the method I employ when forcing forward the required quantity of
gas or other fluid instead of allowing it to pass back. A¹ is the exhauster; D' is
the supplementary exhauster worked by the helical wheels E¹ in such a method
and at such a speed as to equalize the pressure in the large exhausters. The
small supplementary exhauster D¹ is made on the same principle as the large
exhauster A¹.
Figure 8 is an application of a metallic disc or piston connected with the suction
and discharge of the exhausting machinery. The disc is worked by means of a cam

page_text: or a link E', but I do not confine myself to working the piston by a link, as I
employ any suitable motion.
Figure 9 and 9a shews the method I employ of having a moving or sliding piston
or panel in the end plate or cover of the exhauster. The holes F1 are cut in the end
plate the required shape and size, and valves G connected by a screw and hand
wheel H regulate the dimension and shape of the holes F' as the varying quantity
and pressure of the gas requires; I is the loose cover, by which arrangement this
modification can be applied to any exhauster. I fix a valve on both ends of the
exhauster as required.
Figures 10 and 10a are views of the arrangement I use for allowing the gas to
pass back by means of a groove or opening in the cylinder of the exhauster; the
groove is shewn at K.
Figures 11 and 11a are views of an arrangement by which I regulate the pressure
of the exhauster by cutting holes the required shape and dimensions in the segments
of the exhauster, connecting same by pipes with the inlet or outlet as may be
desired; the holes are shewn at A and the pipes B are the pipes alluded to.
In reciprocating exhausting and pumping engines I employ similar modifications
to those I have described, and any experienced mechanic can arrange the parts so
as to secure the desired results, and obtain the advantages of my Invention. The
openings or outlets, however arranged, being graduated and of such proportions as
to secure equality of pressure or vacuum.
Having now described the nature of my said improvements, and in what manner
the same may be carried out, I desire it to be understood that I do not confine
myself to the exact details as herein described, as the same may be varied without
departing from the Invention, nor do I claim the rotary engine or engines here
described as new Inventions, but what I do claim is,―
First. The system or mode of equalizing the pressure and vacuum in gas and
other rotary and reciprocating exhausters and pumping machines, by means of a
revolving cock, cocks, or by-passes, substantially as herein-before described, and
shewn in Drawings.
Second. The arrangement of openings or holes in the slides or shutters of
exhausters or like machines for the purpose herein-before described.
Third. The mode of forcing or pressing the gas or other fluid forward by means
of supplementary machinery, as and for the purpose herein-before described.
Fourth. The mode of equalizing or balancing the pressure of the gas or other
fluid on either side of the exhausting or pumping machinery by means of discs or
pistons, as and for the purpose herein-before described.
Fifth. The modes of working a valve or slide in the end plate or plates or cylinder
covers of such machinery, as and for the purpose herein-before described.
And, Sixth. The introduction of groves or openings in the cylinder or cylinders
of such exhausting or pumping machinery, or in the segments of the same, as and
for the purpose herein-before described.
In witness whereof, I, the said James Eglinton Anderson Gwynne, have
hereunto set my hand and seal, this First day of February, in the year of
our Lord One thousand eight hundred and seventy-nine.
J. EGLINTON A. GWYNNE. (L.S.)