Year: 1887

page_text: Date of Application, 16th Mar., 1887
Complete Left, 10th Dec., 1887
Complete Accepted, 13th Jan., 1888
WILLIAM DONALDSON Civil Engineer 2 Westminster Chambers Victoria Street
Westminster London do hereby declare the nature of this invention to be as
follows
The securing of large portholes for the inlet and exhaust of fluid from the working
cylinder with the least possible amount of expenditure of work in overcoming friction
and in the simplest way.
The improvement refers to the way in which the portholes for the admission of the
motive fluid are opened and closed by a single cylindrical piston valve actuated by the
pressure of the motive fluid admitted through the ports which are opened and closed
by the plunger piston or piston rod without the aid of tappets.
The motor may be either single or double acting.
The accompanying drawings are sectional plans which shew substantially the general
arrangements of the working parts.
Fig. I shews the double motor, P 2 is the piston, Pi the piston rod, which contains
the two passages p. i. for the admission of the fluid to move the valve, and the two
passages p. e. to allow of its escape. V is the valve pierced by the two passages p.
The passages I are the inlet ports, and E the exhaust ports of the cylinder. The
ends of the valve chamber are put in communication with the motive fluid, and the
exhaust by means of the pipes i, and e, respectively or by some other suitable
passages. When the passage p. i. is opposite the pipe i, the passage p. e, at the
other end of the motor is opposite the pipe e. The pressure fluid then enters the
valve chamber, and moves the valve, till the passages p, are opposite, one to the inlet
port I, and the other to the exhaust port E, which communicates with the opposite
end of the cylinder. The pressure fluid then enters the cylinder through the port I
and moves the piston P 2, until the other passage p is opposite the other pipe i.
The valve is then moved in the opposite direction and so the action goes on.
Fig. II shews two single acting motors working together. The plunger piston P 2
contains one passage p. i. for admitting high pressure fluid into the valve chamber
›

page_text: and one passage p, e, for allowing it to be discharged. The valves of the two motors
are connected by the rod R, which may be a C link attached as shewn on a straight
rod working through stuffing boxes. The rest of the letters refer to the same parts
in both figures. When one passage p. i, is opposite one pipe i or other suitable
passage the port p. e. of the other engine is opposite the pipe e, and the high
pressure water enters one valve chamber and moves the valve, the valve of the second
engine being moved by the rod R, until the passage p, in the first motor is opposite
the inlet port I and the passage p, of the second motor is opposite the port E. The
two plungers are connected by the rod P 1. The double acting engine may also be
worked with two separate valves connected by a rod. The motor may be used
either for direct pumping or driving a crank shaft.
Dated this 16th day of March 1887.

page_text: I-WILLIAM DONALDSON Civil Engineer 2 Westminster Chambers Victoria Street
Westminster London 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 :-
The securing of large portholes for the inlet and exhaust fluids from the working
cylinder with the least possible amount of expenditure of work in overcoming
friction and in the simplest way. The improvement refers to the way in which the
portholes for the admission of the motive fluid are opened and closed by a single
cylindrical piston valve actuated by the pressure of the motive fluid admitted through
ports which are opened and closed by the plunger piston or piston rod, without the
aid of tappets. The motor may be either single or double acting.
Fig. (1) is a longitudinal and fig. (2) a transverse sectional elevation of the
motor. The motive fluid is supplied to the inlet ports I, leading to the motive
cylinder C through the passage S and through the passage R which is in connection
with the passage S to the inlet ports i leading to the cylindrical valve chamber.
E are the exhaust ports from the motive cylinder Cand e the exhaust ports from
the valve cylinder c. The passages connect the inlet ports i and exhaust ports e
with the valve chamber c. The valve V is provided with two annular or other shaped
passages O. P is the piston and p the piston rod. The piston rod p is provided
with four annular or other shaped passages D.
In the figure the piston P has just completed its full stroke from left to right and
has brought one of the passages D opposite one of the passages on the right and
another of the passages D opposite one of the passages e on the left. During the opening
of these passages the motive fluid has passed through the passage R and the port i and
passage D on the right to the passage and thence to the valve chamber C, and has in
this interval moved the valve V from right to left, the fluid, which had moved the valve
from left to right escapes through the exhaust port e on the left. This motion of the
valve V brings the right hand passage O opposite the right hand inlet port I and
the left hand port O opposite the left hand exhaust port E. The motive fluid now
enters the motive cylinder on the right and moves the valve from right to left, the
fluid to the left of the piston escaping through the exhaust port E. In a similar
way the piston is again moved from left to right.

page_text: Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is :-
The mode of actuating the valve of a double acting motor, the motive cylinder of
which is provided with inlet and exhaust ports opened by two ports in the valve,
by means of the direct admission and exhaust of the motive fluid through ports in
the piston rod, substantially as described in the specification and in the drawings
which accompany the specification.
n
WILLIAM DONALDSON.