Improvements in Valve Gearing for Duplex Pumping Engines.
Year: 1892

page_text: Date of Application, 22nd Apr., 1892
Complete Specification Left, 21st Jan., 1893-Accepted, 18th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in Valve Gearing for Duplex Pumping Engines.
I PHILIP FRANCIS ODDIE of 12 Rossetti Mansions, Chelsea, in the County of
Middlesex, Engineer do hereby declare the nature of this invention to be as
follows:-
This invention has reference to improvements in the construction and arrange-
ment of the parts of the valve gear of duplex pumping engines, to simplify their
operation and economise cost of construction and maintenance.
In carrying out the invention I employ a double piston, the respective heads
being rigidly connected or constructed so that in operation they partake of the
same reciprocations within a double cylinder or cylinder formed of appropriate
double length to allow of sufficient traverse of each head and provide intermediately
space for a recess or recesses in which to form, or locate removably, a valve face or
plate. The ports of the valve of one double cylinder are covered and uncovered
by means of an inclined part or parts formed on or attached to the double piston
actuating the valve and the stream or other fluid admitted to or emitted from the
other double cylinder of the duplex pumping engine is controlled by the movements
of this valve and correspondingly the admission and emission of steam or fluid to
the first double cylinder is similarly controlled by a valve similarly operated in
this second double cylinder.
Or, instead of the valve being formed with a cooperating face having ports
parallel to the plane of motion of the piston rod the ports may be formed inclined
and be closed and opened by an inclined part attached to or formed with the double
pistons which part itself becomes the valve.
Dated the 22nd day of Anril 1892.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Valve Gearing for Duplex Pumping Engines.
I, PHILIP FRANCIS ODDIE, of 12 Rossetti Mansions, Chelsea in the County of
Middlesex, Engineer do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:—
This invention has reference to improvements in the construction and arrange-
ment of the parts of the valve gear of duplex pumping engines, to simplify their
operation and economise cost of construction and maintenance.
In carrying out the invention I employ a double piston, the respective heads
being rigidly connected or constructed so that in operation they partake of the
same reciprocations within a double cylinder or cylinder formed of appropriate
double length to allow of sufficient traverse of each head and provide intermediately
space for a recess or recesses in which to form, or locate removably, a valve face or
plate. The ports of the valve of one double cylinder are covered and uncovered by
means of an inclined part or parts formed on or attached to the double piston
actuating the valve and the steam or other fluid admitted to or emitted from the
other double cylinder of the duplex pumping engine is controlled by the movements
of this valve and correspondingly the admission and emission of steam or fluid to
the first double cylinder is similarly controlled by a valve similarly operated in
this second double cylinder.

page_text: Or instead of the valve being formed with a coöperating face having ports
parallel to the plane of motion of the piston rod the ports may be formed inclined
and be closed and opened by an inclined part attached to or formed with the
double pistons which part itself becomes the valve.
DESCRIPTION OF THE DRAWINGS.
Figure 1 shews a transverse sectional view of a duplex pumping engine pair of
cylinders and cooperating parts arranged according to my invention, taken on the
line 1-1 of Figs. 2 and 3.
Fig. 2 is a longitudinal section of one of the cylinders and parts, taken on the
line 2–2 of Figs. 1 and 3 but with the piston portions in full for the better
comprehension of their construction.
Fig. 3 is a sectional plan view of the same taken as regards the cylinders and
certain parts on the lines 3-3 of Figs. 1 and 2.
Fig. 4 shews a detail being a view of the side of one of the double pistons a-a
in order more clearly to indicate the form of the inclined plane e for actuating
the valve f.
Fig. 5 is side view of the part of the valve f which faces the incline e and
the slot of which f¹ receives within it the said inclined plane or fin, and is
thereby moved in a partially rotative direction.
Figs. 6, 7, and 8 are three views taken on the lines 1-1 of Figs. 2 and 3
shewing in section the valve f in three different positions or stages of the move-
ment imparted to it by the longitudinal motion of the incline e, Fig. 6 indicating
the valve in the cylinder A (say) whilst it is at commencement of its stroke
Fig. 7 its position midway and Fig. 8 its position at the end thereof or when
respectively the portion 4, 5 and 6 of the incline (see Fig. 4) are operating the
valve f.
a a are each pistons in pairs mounted on the hollow stem a² and connected by
the rod a³ to the pump to be worked thereby.
Each double piston a, a' reciprocates within the parts b, b¹ of the double
cylinder A or B, as the steam pressure is caused to act upon the outer faces of the
said pistons a, a, the supply of steam being controlled as regards its ingress and
egress to and from the cylinder A by the incline e of the double piston in the
cylinder B and the supply to the cylinder B by the corresponding incline on the
other double piston actuating the corresponding valve to the steam passages of
the cylinder A. c is a recess around each cylinder A and B in which is located
the valve face provided with the ports i for the steam and these ports, one set to
each cylinder, are each covered by a valvef and this valve is operated to cover and
uncover these ports by means of the incline e already described.
In order whilst permitting longitudinal motion to the pistons, a, a¹ to prevent
their rotation, each pair are connected by a slotted bar a into the slot of which
passes the end of a pin g secured in the casing of the recess c of each cylinder and
by corresponding screw threading these pins are capable of being adjusted to the
slotted bars, and these pins 9 take a guiding hold in these slots.
The shafts or rods a³ of the pistons a, a² are at a packed by means of suitable
packing enclosed within the gland a which gland has a screw threaded sleeve a²
which engages a screw threaded collar a fixed in the cover be of the pump end 6*.
a is a block nut engaging the sleeve a' and serving to fix it in its adjusted
position.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In valve gearing for "duplex" pumping engines, the combination or arrange-
ment and use of an inclined guide way or part integral with the double pistons

page_text: of steam to the companion or duplicate cylinder substantially as and for the
purpose hereinbefore described and shewn.
2. The combination or arrangement and use with the double piston, in each
cylinder, of a "duplex" pumping engine of an inclined plane or guiding part
-as e, integral with said piston, and serving as the means for actuating the
valve of the steam ports controlling the direction of flow of steam, to the com-
panion or coöperating double piston of the duplex pumping engine substantially
as set forth.
Dated the 21st day of January 1893
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.