IMPROVEMENTS IN AND CONNECTED WITH MOTIVE- POWER ENGINES, ALSO, APPLICABLE TO WATER METERS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Allan Andrews, junior, at the Office
of the Commissioners of Patents on the 24th December 1880.
ALLAN ANDREWS, junior, Brittania Engine Works, Kilmarnock, in the County
of Ayr, North Britain. "IMPROVEMENTS IN AND CONNECTED WITH MOTIVE-
POWER ENGINES, ALSO, APPLICABLE TO WATER METERS."
This said Invention has reference to special new or improved constructions or
arrangement and combinations of the valves and their fittings for reversing the
action of reciprocatory motive-power engines and fluid meters, such as non-rotative
or direct-acting steam pumps, direct-acting air compressing or blowing steam
engines, or other direct-acting reciprocating steam engines for other purposes, such
as for working the air-pumps of larger engines, and the water circulating and feed
pumps for these, or for steam hammers, stampers, and such like direct-acting steam
engines, or water engines and meters; and which improvements will make such
engines or meters more efficient and regular in their action at any desired speed,
with less liability to stoppage and derangement from the displacement of their
controlling steam valves and gear, and more permanently durable against the effects
of wear and tear than other engines of this class heretofore.
In the new or improved combinations of this Invention, the construction and
arrangement of the steam cylinder and its ordinary slide (or other equivalent
reversing) steam valve and its casing, with the inlet and exhaust steam ports to
the cylinder, may all be constructed and fitted in any of the ordinary ways
heretofore used or adopted and preferred; and the construction and arrangement
of the frame, and that of the pump, compressor, hammer, or other machines or
apparatus to be driven by the engine or its piston, and the mode of attachment of
these several parts may all be as heretofore, or as convenient for the purpose to
which the engines are to be applied, but by the improvements of this Invention,
the main reversing steam slide valve is worked or reciprocated to and fro direct by
a small piston working steam-tight, preferably in a close ended steam cylinder
fitted at one end of the casing, so that the rod of this piston may work through a
stuffing box or stuffing boxes fitted between them direct into the casing of the
main steam or slide valve, so as to be attached thereto and work it. An essential
feature of novelty of the Invention and all the arrangements or combinations of it,
consists in the construction and arrangement of an oscillating nearly cylindrical or
slightly tapered (preferably hollow) valve, working steam-tight in a corresponding
7

page_text: hollow steam chest, preferably supplied with steam from the main steam casing
and fitted with a screwed on end cover, and formed or fitted at one side of the
small cylinder with the piston, the action of which it controls, so as to work the
main slide valve. The face plate or side of the small cylinder is formed with an
inlet and an exhaust port, angled from the opposite ends of the cylinder to the
working face of the casing, the former led from the extreme ends of the cylinder
towards the ports in the face of the valve, and the latter at such a distance from
the ends of the cylinder as to leave and enclose sufficient of the exhaust steam
beyond these ports as to cushion the piston at each end after it passes and cuts off
the further escape of the steam through these exhaust ports. The inside of the
central working parts or faces of the valve and its casing.are formed with their
exhaust ports or chambers opposite each other, the latter with the usual escape
branch, and with a short transverse bearing face between the central chamber and
the adjacent angled exhaust ports from the cylinder, and also the inlet ports
properly divided, while the oscillating circular valve face is formed with a
corresponding broad bearing face on each side of its central close exhaust chamber,
properly closing or covering the two ports from opposite ends of their cylinder
when set in its central or mid position. The valve is formed with a segmental
inlet steam space or recess on each side beyond these bearing faces, to which the
steam is or may be admitted, either from the central chamber of the valve when it
is made hollow, or from either end of the valve case when made solid, and
admitted by a branch from the steam pipes, or from the main valve casing, as
desired; all so that as this valve of the small cylinder is oscillated by the
reciprocatory action of the piston of the engine (or its rod or tappet passing out
through the end of the engine cylinder) as it nears either end of its stroke; this
admits the steam to that end and exhausts it from the other end of the small
cylinder and its piston, which works the engine steam valve, so as to reverse it
and the main piston at the proper time, alternately and respectively from either
corresponding end as the piston approaches, and before it reaches to strike the ends
of the cylinder. Several arrangements of fittings may be used for so actuating or
oscillating the round valve of the small cylinder and piston for working
the steam slide valve of the engine cylinder, one of which arrangements
consists in fitting a long tappet rod within the piston rod made hollow for that
purpose with a tappet head on its inner end, and having the other end working out
through the back end of the piston, and a stuffing box in that end of the cylinder
cover within a fixed hollow protecting case or trunk, and having rack teeth formed
on one side of this rod gearing into the corresponding teeth of a segmental rack
formed round the central part of the circumference of the round valve on the opposite
side to that of its working face and exhaust and steam passages or ports, all so
as to turn or oscillate the valve to the required distance to and fro, to open and
close its opposite steam and exhaust ports, and so reverse the engine by the action
of its piston as it nears the opposite ends of its stroke. On the outward. stroke
the bottom of the hollow piston rod strikes and pushes out the tappet rod to move
the valve, while on the extreme inner stroke of the piston, a coller plate on the
outer end of the piston catches a shoulder on the inner end of the tappet
rod and pulls it in to move the valve, all otherwise substantially as hereinbefore.
described, to reverse the main steam slide valve and piston at each end of its
stroke, which is there cushioned by enclosing a portion of the exhaust steam at
each stroke to prevent the piston striking the ends of the cylinder.
In this new combination of small cylinder with its controlling oscillating circular
steam valve and casing (worked by a tappet rod from the piston of the engine
cylinder, all for working its main slide valve) under one arrangement, the small
cylinder and its steam valve casing and trunk for the tappet valve rod working in,
might all be cast in one piece on the end cover of the engine cylinder, or that and
its casing combined, or with the stuffing box piece of these only, all so that the
stuffing boxes with their bushed recesses.could be accurately bored in line for their
piston, valve, and tappet rods, to work truly through, and also so that the flanges

page_text: and screw bolts of the end covers would carry the whole without other framing or
bracket attachments, or in some cases, as for larger sizes, a double stuffing box
piece could be cast separately with its end flanges forming the covers of the engine
cylinder, and its slide valve casing on one end, and the end covers of the small
cylinder and trunk pipe for tappet rod on the other end, and so secure the whole
without other carrying attachments. In either arrangement a steam passage
could be cast in the solid piece between the two valve casings to lead the steam
from the main casing to the casing of the oscillating valve; and for small horizontal
steam pumps of this description the small steam cylinder and its oscillating valve
could be fitted either at the outer free end of the steam cylinder of the engine, or
the end next or between it and the end of the pump, cylinder, or barrel; in which
case they might be cast in one with the intermediate end piece or casting, having
the covers and stuffing boxes of the cylinder and pumps formed on it, and in this
case the cylinder and pump would be set a little further apart for this purpose,
and have a short tappet rod working through stuffing boxes in both the cover of
the cylinder and pump barrel, so as to be moved in one direction by the piston of
the cylinder at the end of its instroke and in the other direction by the piston
of the pump barrel at its instroke, and so reverse the oscillating valve of the
small cylinder by the toothed rack on the tappet rod gearing into the toothed
segment on the valve, all otherwise substantially as herein-before described by the
central tappet end working in the hollow rod of the steam piston. But instead of
the toothed rack and segmental wheel on the valve, a single strong lateral projection
might be formed on the tappet rod working into a steel faced gap in the back face
of the oscillating valve, fitting it freely with very little lateral play or vibration. Or
otherwise by another arrangement the oscillating valve might be formed with a
spindle working out through a stuffing box in the end of its steam casing and
with the lever and spanner fixed on it outside, the free end of which would project
down into a slot or gap formed between pushing heads on the tappet rod in the
middle part between its stuffing boxes in the adjacent end covers of the steam and
pump cylinders; or these tappets might work separately in their stuffing boxes,
having the outer pressing heads acting against the free end of the oscillating lever of
the valve, which would thus be actuated to admit the steam to and exhaust the steain
from the small cylinder, and reverse the main slide valve and engine, all otherwise
substantially as described in reference to the other modifications. Other equivalent
arrangements of tappet rods might be devised to work the new oscillating steam
valve of the small cylinder and piston from the motion of the engine piston or
pump or other rod moved by it, all for reversing its slide valve and the engine at
each end of the stroke of its piston, but these would all require to act substantially
as and in the manner of the several tappet motions herein described.
For small direct-acting steam pumps the whole combination would be self-
contained and portable without other framing than a broad flanged stool cast on
the side of the steam cylinder and oue on the barrel of the pump, by which the
whole could be secured with screw bolts to a suitable foundation or strong wall,
or equivalent horizontal or vertical beams of wood without other fixtures or
framing.