Improvements in and connected with Hydraulic Pumps.
Year: 1899

page_text: Date of Application. 2nd Mar.. 1899
Complete Specincation Lert, 4th Dec., 1899-Accepted, oth Jan., 1900
PROVISIONAL SPECIFICATION.
Improvements in and connected with Hydraulic Pumps.
We, HUGH HOLMES MACTAGGART, of 53, Dudley Avenue, Leith, and ROBERT
GRIGOR SCOTT, of 13, Dryden Place, Edinburgh, Scotland, Engineers, do hereby
declare the nature of our invention to be as follows:-
Our invention relates to improvements in and connected with hydraulic pumps
whereby certain advantages are obtained.
In order to render the description of our invention clearer we have appended
a sheet of drawings in which
Figure 1 is a sectional elevation.
Figure 2 is a plan.
Figure 3 is a sectional elevation of the valve employed, while Figure 4 is a
true section in another plane of the said valve.
The drawings appended show one form of the invention.
In the drawings A is the motor cylinder and it will be noticed that in the form
of pump shown in Figure 2 three of these are used or in other words the pump
shown is threefold.
The motor cylinders A are so formed as to constitute the plungers of the pumps
and pass through the stuffing boxes of the pump barrels.
The pressure water is admitted by means of the balance slide valve, to be
hereafter described, to the motor cylinders through the interior of the fixed
pipes B. These pipes pass through the packed glands and stuffing boxes of the
motor cylinders and form as it were the fixed rams of the cylinder A.
It is to be noted that although the motor cylinders or plungers are shown in
the drawing as being formed in one piece the plungers can, when found desir-
able, be formed of cylindrical pieces of greater or less diameter than the exterior
of the water cylinder bolted or otherwise suitably attached to the motor cylinders.
It would be practicable to have another fixed pipe or ram with sliding cylinder
coupled or otherwise connected to the sliding cylinder A but projecting in the
opposite direction. The said combination of ram and cylinder to be essentially
the same as that shown by A and B in Figures 1 and 2 and to have the motive
power water distributed and regulated as described for the single combination
of A and B.
The motor cylinders A have attached to them gudgeon pins a as shown which
work in the heads 6 of the forked connecting rods. These connecting rods are
in turn connected to the equidistant cranks e of the crank shaft d. By this
means the working or forward stroke of one or more of the motor cylinders
causes the exhausting or back stroke of the other or others.
The valve for distributing and regulating the motive power water to the motor
cylinders shown in the drawings is of the balance slide type.
It consists essentially of a casing D with a valve spindle E passing through
suitable packing glands and stuffing boxes. The spindle is bridled and through
the eye of the bridle there passes a cylindrical piece F on which is mounted the

page_text: small ring valve G packed with leather as shown. Through F there is a channel
or opening shown in dotted lines in Figure 4.
The ring G receives the to-and-fro motion of the spindle and is moreover free
to rotate on the piece F. The ports for this valve are arranged as shown with
their edges similarly curved to the cut-off and exhaust edges of the valve ring G.
The port which leads to the cylinders is set on one side as shown in Figure 3
and is curvilinear as shown in this figure, so that the frictional differences on
opposite sides of the valve axis may tend to cause its slight rotation on the
cylindrical piece F whereby any wear of the valve face may be adjusted.
The valve is balanced by having an exactly similar valve ring G¹ on the other
end of the cylindrical piece F and, as has been before pointed out, by having a
passage through F communicating with the interior of both rings.
The distributing action of the valve is preferably obtained from the radial
motion of the connecting rods.
The valves just described are bolted or otherwise fixed to the pipe branches C
and the valves are actuated as required by means of the side rods e¹ which are
in turn coupled to the connecting rods f
It will be clear to those skilled in the art that the particular form of our
invention which we have herein described and illustrated might be altered to
a considerable extent without departing from the spirit of our invention.
As an example; it is clear that instead of three coupled pumps we might
employ fewer or more according to requirements.
It is further clear that the plungers might have a tail-ram or extension piece
of less diameter passing through a packing gland and stuffing box in the extreme
end of the pump casing and it is also obvious that another form of valve or
valves and a different method of actuating than that described might be
employed.
improvements in ana connected with hyuraum umps.
We, HUGH HOLMES MACTAGGART, of 53, Dudley Avenue, Leith, and ROBERT
GRIGOR SCOTT, of 13, Dryden Place, Edinburgh, Scotland, Engineers, do hereby
declare the nature of our invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
Our invention relates to improvements in and connected with hydraulic pumps
whereby certain advantages are obtained.
In the drawings left with the Provisional Specification
Figure is a sectional elevation.
Figure 2 is a plan.
Figure 3 is a sectional elevation of the valve employed, while Figure 4 is a
true section in another plane of the said valve.
The drawings appended show one form of the invention.
In the drawings A is the motor cylinder and it will be noticed that in the form
of pump shown in Figure 2 three of these are used or in other words the pump
shown is threefold. It is not an essential part of our invention that the pump
should be threefold as we could employ a greater or smaller number of cylinders.

page_text: The motor cylinders A are so formed as to constitute the plungers of the pumps
and pass through the stuffing boxes of the pump barrels.
The pressure water is admitted by means of the balance slide valve, to be
hereafter described, to the motor cylinders through the interior of the fixed
pipes B. These pipes pass through the packed glands and stuffing boxes of the
motor cylinders and form as it were the fixed rams of the cylinder A.
The fixed pipes B are for convenience attached to the sole plate casting or
to other casting or castings attached thereto thus permitting ready access and
removability if necessary.
The construction of the motor cylinders just described avoids the necessity
of a passage cast in the side to admit the motive water a system which necess-
arily contracts the area of the passage and weakens the castings.
It is to be noted that although the motor cylinders or plungers are shown in
the drawing as being formed in one piece the plungers can, when found desir-
able, be formed of cylindrical pieces of greater or less diameter than the exterior
of the water cylinder bolted or otherwise suitably attached to the motor cylinders.
It would be practicable to have another fixed pipe or ram with sliding cylinder
coupled or otherwise connected to the sliding cylinder A but projecting in the
opposite direction. The said combination of ram and cylinder would be essentially
the same as that shown by A and B in Figures 1 and 2 and would have the motive
power water distributed and regulated as described for the single combination
of A and B.
It is further clear that the plungers might have a tail-ram or extension piece
of less diameter passing through a packing gland and stuffing box in the extreme
end of the pump casing.
The motor cylinders A have attached to them gudgeon pins a as shown which
work in the heads of the forked connecting rods. These connecting rods are
in turn connected to the equidistant cranks e of the crank shaft d. By this
means the working or forward stroke of one or more of the motor cylinders
causes the exhausting or back stroke of the other or others.
One form of valve that we use for distributing and regulating the motive
power water to the motor cylinders is shown in the drawings and is of the
balanced slide type.
It consists essentially of a casing D with a valve spindle E passing through
suitable packing glands and stuffing boxes. The spindle is bridled and through
the eye of the bridle there passes a cylindrical piece F on which is mounted the
small ring valve G packed with leather as shown. Through F there is a channel
or opening shown in dotted lines in Figure 4.
The ring G receives the to-and-fro motion of the spindle and is moreover free
to rotate on the piece F. The ports for this valve are arranged as shown with
their edges similarly curved to the cut-off and exhaust edges of the valve ring G.
The port which leads to the cylinders is set on one side of the spindle as shown
in Figure 3 and is curvilinear as shown in this figure, so that the frictional
differences on opposite sides of the valve axis may tend to cause its slight rota-
tion on the cylindrical piece F whereby any wear of the valve face may be
adjusted.
The valve is balanced by having an exactly similar valve ring G¹ on the other
end of the cylindrical piece F and, as has been before pointed out, by having a
passage through F communicating with the interior of both rings.
The distributing action of the valve is preferably obtained from the radial
motion of the connecting rods.
The valves just described are bolted or otherwise fixed to the pipe branches C
and the valves are actuated as required by means of the side rods c¹ which are
in turn coupled to the connecting rods f
It will be clear to those skilled in the art that the particular form of our
invention which we have herein described and illustrated might be altered to
a considerable extent without departing from the spirit of our invention.

page_text: Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
(1) In hydraulic pumps the arrangement and combination of movable motor
cylinders actuated through connecting rods by equidistant cranks with fixed
pipes forming the motor ram substantially as described and illustrated.
(2) In hydraulic pumps the arrangement and combination of parts whereby
the motor water is admitted through the interior of the fixed pipes forming the
motor rams.
(3) In hydraulic pumps as above described and illustrated a valve of the
balanced slide type wherein the valve ring has a curvilinear port communicat-
ing with the cylinder set on one side of the axis whereby the frictional differ-
ences on the opposite sides of the valve axis tend to cause a slight rotation of
the ring thus equalizing the wear.
Dated the 1st day of December 1899.
For the Applicants,
LORRAIN & PURVIS,
53, York Place, Edinburgh.