Year: 1887

page_text: Date of Application, 29th June, 1887
Complete Left, 29th Mar., 1888
Complete Accepted, 18th May, 1888
We, JAMES GRIFFITHS, of 28 Caroline Street, Newport, in the County of
Monmouth, sailmaker, and JOSEPH MONTESQUIEU ANTHONY, of Sneyd Park, in the
County of Gloucester, merchant, do hereby declare the nature of this invention to be
as follows:-
:-
The improved equilibrium slide valve in which this invention consists is composed
of a pair of pistons contred at a requisite distance apart on a spindle which with the
pistons is contained within a peforated tube situated over the ports of the cylinder.
The ports are governed by the pistons. The perforated tube is partially enclosed in a
chest which is itself contained within a second or outer chest. The second chest is
divided into compartments corresponding to the ports of the cylinder. The perforations
in the tube are arranged in series of which one series is situated, midway in the
length of the tube and lies over the exhaust port. Two other groups or series of
perforations lie over each of the supply ports respectively and beyond these there
is further towards each end of the tube a series of similar perforations. The tube
is preferably inserted at the extremities in recesses or openings formed in the ends
of the outer chest.
Steam is admitted to the outer chest from a steam pipe and passes thence into the
tube by the perforations situated, as aforesaid, towards the ends thereof. The steam
consequently acts against both pistons which are therefore in equilibrium. As, by
its actuation by the eccentric, the spindle is reciprocated in the tube and the pistons
are removed from and re-presented to the perforations therein the steam is admitted
to the supply ports in regular turn through the perforations situated above them and
is exhausted through the perforations above the exhaust port. Similarly with motive
agents other than steam. The pistons may consist each of a single disc furnished with
a packing ring or of a group of such discs. They are adjustable on the spindle by
nuts or other means.
If, instead of being admitted to the tube in the way above mentioned, the steam be
supplied directly to the perforations in the tube which are situated above the
exhaust port, the steam is alternately supplied and exhausted through the end
ports. It is then exhausted into the outer chest and forms a steam jacket to the
inner chest.

page_text: By thus diverting the course of the steam an engine may be reversed without the
employment of ordinary reversing gear, a four-way cock governing the steam and
exhaust pipes being alone necessary.
With steam pipes of large diameter the direction of the steam or other motive agent
may be changed by applying a valve and perforated tube thereto similar in construction
to those above described.
W LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicants.
COMPLETE SPECIFICATION.
An Improved Equilibrium Piston Slide Valve.
We, JAMES GRIFFITHS, of 28, Caroline Street, Newport in the county of
Monmouth, sailmaker, and JOSEPH MONTESQUIEU ANTHONY of Sneyd Park in the 1
county of Gloucester, merchant, 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 improved equilibrium valve in which this invention consists is composed of a
pair of pistons centred at a requisite distance apart on a spindle which with the
pistons is contained within a perforated tube situated over the ports of the cylinder.
The perforated tube is partially enclosed in a chest which is itself contained within a
seconil or outer chest. The inner chest is divided into compartments corresponding to
the ports of the cylinder. The perforations in the tube are arranged in groups or
series one of which is situated midway in the length of the tube and lies over the
middle port. Another group or series of perforations lies over each of the end ports
respectively, and beyond these there is, further towards each end of the tube, a series
of similar perforations. The tube is preferably inserted at the extremities in apertures
formed through the ends of the outer chest.
Steam is admitted to the outer chest from a steam pipe and passes thence into the
tube by the perforations situated, as aforesaid, towards the ends thereof. The steam
consequently acts against both pistons which are therefore in equilibrium. As, by its
actuation by an eccentric on the driving shaft, the spindle is reciprocated in the tube,
ihe steam is admitted to the end ports in regular turn through the perforations situated
above them and is exhausted through the tube by way of the perforations above the

page_text: middle port.
Similarly with motive agents other than steam. The pistons may
consist each of a single disc furnished with a packing ring or of a group of such
discs. They are adjustable on the spindle by nuts or other means. Consequently
provision is made for adjustment of "cut-off."
If, instead of being admitted to the tube in the way above mentioned, the steam
be supplied directly to that series of perforations in the tube which is situated above
the middle port, the steam is then admitted by the end ports alternately to the
cylinder and is also exhausted through the said end ports. The exhaust steam from
the end ports passes out through the end perforations in the tube into the outer chest
where it forms a steam jacket to the inner chest.
By thus diverting the course of the steam an engine may be reversed without the
employment of ordinary reversing gear, a four-way cock governing the steam and
exhaust pipos being alone necessary.
With pipes of large diameter the direction of the steam or other motive agent
may be changed by applying a valve and perforated tubo thereto similar in construc-
tion to those above described.
Referring to the accompanying sheet of illustrative drawings, Fig. 1 thereon
represents a vertical section of a cylinder fitted with an improved valve constructed and
arranged in accordance with this invention. Supported at each end in bearings in
the ends of the outer steam chest a and at different points throughout its length in an
inner steam chest is a tube perforated towards each end and above the middle
port d and e and above the middle port f. Fig. 2 represents a plan of the chests a
and 6 with the covers removed. The chest is divided into compartiments
corresponding to the ports of the cylinder. !
Extending through the tube c is the valve spindle on which are centred a pair
of pistons and fitting the tube. The valve pistons and jare represented at Fig. 1
of the drawings as screwed on the spindle h, but they may be otherwise secured
upon it.
Steam admitted to the outer chest a by the pipe 9 circulates about the exterior of
the inner chest and passes into the tube through the perforations at each end
thereof. The steam acts equally against both pistons i and j, and as the spindle is
reciprocated in the tube by the action of an eccentric connected thereto and carried
on the driving shaft, the valve pistons i and admit and exclude the steam to and from
the ports d and e in regular succession.
The steam is exhausted through the said ports and e alternately and thence through
the tube e into the middle port which communicates with the exhaust or blast pipe
as ordinarily. Similarly with motive agents other than steam; compressed air, for
instance.
to
The valve pistons and jare represented in the drawing as composed of two separate
discs, each fitted with packing rings. The discs are adjustable on the spindle
admit of adjustment of "cut-off" and they may be locked at any desired point on
the spindle or apart from one another by lock nuts or other equivalent means. More
than two of such discs may be used and they may bear one against the other or be⚫
adjusted apart by washers or nuts interposed between them.
If, instead of being admitted to the outer chest a, as herein before described, the
steam be admitted through the pipe which is in communication with the middle port,
and which constitutes in the arrangement above described the exhaust pipe, the
steam entering the tube through the perforations situated midway therein is thereby
supplied to the ports d and alternately from the space between the inner faces of the
valve pistons and j, and, on being exhausted through the said ports d and
passes into the outer chest a by the perforations at the ends of the tube c.
P
it
Thence it passes out through the pipe which, in the arrangement first before
described, is that by which the steam is supplied.
By thus diverting the steam, an engine may be reversed at will, as the pressure of
the steam is transferred from one side of the piston of the steam cylinder to the other,
and, by means of a four-way cock controlling the two pipes communicating with the
outer and inner chests and fitted with an exhaust pipe common to both, the steam or

page_text: other motive agent may be directed to the inner or outer chest and the motion of the
driving shaft of an engine reversed accordingly as desired.
The valve may be itself used as a equilibrated cock for diverting steam or other
motive agent at will from one channel, pipe or conduit to another.
Having now particularly described and ascertained the nature of this invention,
and in what manner the same is to be performed, we declare that what we
claim is :-
1. The improved valve, for steam and other engines, consisting of a tube such as c
perforated towards each end and above the working cylinder ports and containing
pistons such as i and j, against which the steam or other motive agent acts equally on
both sides, and carried on a spindle such as h, reciprocated by an eccentric on the
driving shaft, or by other means, the said perforated tube being passed through an
inner chest such as contained within an outer chest such as a, the parts being
constructed and arranged for the supply and exhaust of the motive agent to and from
the working cylinder, such agent being admitted to the tube either by the end perfora-
tions or by the perforations situated at or about midway therein, substantially as herein-
before described with reference to the accompanying sheet of illustrative drawings.
2. The valve piston discs adjustable to and from each other on the valve spindle h
and constituting the adjustable valve pistons and for opening and closing the end
ports of the working cylinder, substantially as herein before described.
3. The improved valve constructed, arranged and operating substantially as herein-
before described, by a lever or other means, as a cock for diverting the direction from
one pipe or channel to another of steam or other motive agent passing or flowing
through such pipes or channels.
Dail
1 1000