AN IMPROVED PUMPING ENGINE.
Year: 1879

page_text: LETTERS PATENT to John McInnes, of Glasgow, in the County of Lanark,
North Britain, Engineer, for the Invention of "AN IMPROVED PUMPING
ENGINE.'.
Scaled the 27th January, 1880, and dated the 30th July 1879.
PROVISIONAL SPECIFICATION left by the said John McInnes at the Office
of the Commissioners of Patents on the 30th July 1879.
"
JOHN MCINNES, of Glasgow, in the County of Lanark, North Britain, Engineer.
AN IMPROVED PUMPING ENGINE."
This Invention, which relates to a new or improved pumping engine, has for its
objects the production of an, engine for compressing air or gas, or for pumping
liquids, in which the valves for admitting and exhausting the steam to and from
the steam cylinders operate noiselessly, or nearly so, and by which improvements
stuffing boxes for the exhaust and admission valves are dispensed with. This
object is effected by providing the steam cylinder with a tappet at either end
passing through the cylinder cover, and so situated that the piston of the engine
forces them outwards at the termination of each stroke.
These tappets are
connected to the stem of reversing valves, being carried moveably in brackets-
attached to that stem so that the action of the piston upon these tappets reverses
the valves at the termination of each stroke. The object of these reversing valves
is to lead some of the steam alternately to pistons on opposite ends of a rod between
which are carried four other pistons or their equivalents for opening and closing
admission and exhaust ports in the cylindrical casing in which these valves are
contained. By this arrangement there are six pistons on a common stem, the two
end ones being preferably of larger area than the intermediate ones. The end
pistons have respectively a chamber above and below them wherein the cushioning
of their strokes at their termination is effected...
VI.
The foregoing description applies to an engine, placed vertically, but it is to be
understood that the arrangement is the same when the engine.is placed horizontally
i

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John McInnes in the Great Seal Patent Office on the 29th January
1880..
"
JOHN MCINNES, of Glasgow, in the County of Lanark, North Britain, Engineer.
AN IMPROVED PUMPING ENGINE."
..
My said Invention relates to pumping engines of the kind used for pumping or
compressing air or other gas or a liquid, in a direct manner without a rotating
shaft, and the principal objects, aimed at in designing my improved engine are the
obtainment of an improved, arrangement of valves operated without external
connections, the avoidance of stuffing boxes, and the diminution of noise in the
working of the valves.
In carrying out the Invention the cylinder has fitted at each end of it a tappet
to be moved by the piston when completing its stroke; and the two tappets
alternatively move. a pair of valves which admit the steam or other motive fluid
to act alternately on two pistons fixed on the opposite ends of the main valve
spindle so as to move that spindle. The spaces in which the end pistons of the
main valve work communicate with the exhaust pipe or atmosphere by passages
which are covered by the pistons before completing their strokes, in consequence of
which a quantity of steam or air is confined so as to act as a cushion to stop the
motion of the main valve without noise.
And in order that my said Invention and the manner of performing the same
may be properly understood I hereunto append a Sheet of Explanatory Drawings
to be hereinafter referred to, and representing my improved pumping engine. In
these Drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
Figures. 1, 2, and 3 of the accompanying Drawings are different longitudinal
sections of the cylinder and valve passages of the pumping engine; and Figure 4 is
a cross section. In an enlargement at one side of the cylinder there are formed
parallel to the cylinder three cylindrical bores 5, 6, 7, which are closed by end
covers or plugs after the internal parts are completed, and of which one, 5, contains
the main valve, and another, 6, the auxiliary valve, whilst the other, 7, is a passage
communicating with the exhaust pipe 8. In the main-valve bore or chamber 5
cylindrical lining pieces are fixed, which have various ports and passages con-
veniently formed in them, and which diminish the area of the bore excepting at
the ends. Cylinder passages 9, 10 (Figure 3), communicate with passages formed
round the valve-chamber lining pieces and thence through several small holes
with the interior of the valve chamber. In Figure 1 the section is taken
through the exhaust passage 7 and the auxiliary-valve chamber 6; in Figure 2
the section is through the main-valve chamber 5 and the auxiliary-valve
chamber 6; and in Figure 3 it is through the main-valve chamber 5, and the
cylinder passages 9, 10.
The main valve consists of a spindle having fixed on it four small pistons 11, 12,
13, 14, working inside of the lining pieces of the valve chamber 5 and two larger
pistons 15, 16, working in the larger end parts of the chamber. The two innermost
pistons 12, 13, constitute the valve, the other small pistons 11, 14, merely serving
to divide the spaces between them and the larger pistons 15, 10, which object might
be attained by substituting fixed diaphragins with provision for the spindle to work
through them with as little leakage as possible. The several pistons are packed

page_text: passage
with elastic rings, and are fixed in their proper places on the spindle by means of
interposed tubular distance pieces and screw nuts at the ends. The steam or other
motive fluid supplied by a passage 16 (Figure 4) has access to the middle space
between the two innermost valve pistons, 12, 13, and with the parts in the positions
in which they are represented in the Figures, passes thence by the cylinder
9 to the underside of the piston 17. On the piston 17 reaching the upper end of
its stroke it will push up a tappet spindle 18, the bottom end of which then projects
into the cylinder. This tappet spindle 18 has on it two collars which fit and work
easily in a cylindrical bore formed for the purpose in the cylinder.end.or.cover, and
the inner collar closes the opening into the cylinder through which the inner end
of the spindle projects when the spindle is in its innermost position. The bore in
which the tappet spindle 18 works communicates by a lateral slot with the end of
the auxiliary-valve chamber or bore 6, and through this slot there projects a gab
or fork 19 which embraces the tappet spindle 18 between its collars, and which is
formed on a partly cylindrical block 20 fixed on the auxiliary-valve spindle 21.
At the other end of the cylinder and auxiliary-valve bore 6 there are similar parts,
namely, a collared tappet spindle 22, gab 23, and block 24; the last fixed on the
other end of the spindle 21. On the valve spindle 21 there are fixed two small
valve blocks 25, 26, externally cylindrical, but made with cavities like ordinary
slide valves, which cavities are always in communication by ports 27, 28, with the
exhaust passage 7. The space between the valves 25, 26, receives steam by a
passage 29 communicating with the middle of the main-valve chamber 5. Near
the ports 27, 28, ports and passages 30, 31, communicate with the spaces 32, 33,
between the large pistons 15, 16, and the small pistons 11, 12, on the main valve
spindle; and the movements of the auxiliary valve spindle 21 produced by the
tappet spindles 18, 22, put these ports 30, 31, alternately in communication with
the steam inlet 29 and one or other of the outlets 27, 28. With the parts in the
positions delineated the next movement of the auxiliary valves will be upwards,
and will cause steam to enter under the upper large valve piston 15 so that the
main-valve spindle will be raised, and steam will in consequence have access to the
upper cylinder passage 10 instead of the lower one 9. The space above the valve
piston 15 is closed, excepting a passage 34 leading to the exhaust passage 7 or to
the atmosphere; this passage 34 is however covered by the piston 15 before the
latter reaches the end of the space and air or steam is in consequence confined in
the space so as to act as a cushion and arrest the motion of the valve spindle
without noise. On the return stroke the other valve piston 16 acts in a similar
way, the space beneath it having an outlet 35 which the piston covers before
reaching the end of the space. When the engine is placed vertically as shown in
the Drawings the upper valve piston 15 is made larger than the lower one 16 in
order to compensate for the weight of the valve pistons and spindle; and a small
loose pin 36 passing through a stuffing box at the bottom end of the main-valve
chamber 5 is provided for raising the main valve.for starting the engine if required.
The exhaust of the main cylinder takes place through one or other of the passages
9, 10, in the ordinary way, through the spaces between each innermost valve piston
12, 13, and the next outer pistons 11, 14, thence through holes in the lining pieces,
and through passages 37, 38, into the exhaust passage 7.
Having thus particularly described my said Invention, and the manner of
performing the same, I have to that I do not restrict myself to the precise
details herein described or delineated; but that what I believe to be.novel and
original and claim as the Invention secured to me by and in terms of the herein-
before in part recited Letters Patent is,-
1. The arranging or combining together of the valve apparatus of pumping
engines substantially in the improved manner hereinbefore described.
2. The combination of parts comprising the main-valve details with the actuating
istons and passages substantially as hereinbefore described.

page_text: 3. The combination comprising the auxiliary-valve details with the tappet spindles
substantially as herein before described.
In witness whereof; I, the said John McInnes, have hereunto set my hand and
seal, this Twenty-seventh day of January, in the year of our Lord One
thousand eight hundred and eighty..
1
"
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JOHN MINNES. (L.S.)