Year: 1889

page_text: Date of Application, 14th Oct., 1889
Complete Specification Left, 19th May, 1890-Accepted, 20th Sept., 1890
Description 1st. Slide valve is swung by the centre of each end attached to the
centre of a pair of levers attached to moveable links fixed at one end of said levers
and to a fixed pin in side of steam chest or independent frame and to the other end
of levers by another pair of links to a moveable crosshead spanning across steam chest
working in suitable guides at each end of crosshead fixed to side of steam chest or
frame.
Links attached to ends of levers vice-versa as in a motion.
Balance piston rod or rod passing through gland on steam chest cover or balance
cylinder cover, said rod is attached to centre of said crosshead by a double eye and
bolt with direct action bell crank or geared wheels by indirect action to allow cross-
head free action to act on levers when drawn or acted on by the balance piston or
rod passing through gland and through adjustable wedges up through a bow seated
on balance cylinder or steam chest cover as the case may be, thence through a spiral,
buffer or other spring taking a screwed nut, wheel or handle mounted on said spring
or buffer protected by suitable washers to be acted on at will by screwing nut, wheel
or handle and automatically by steam pressing on balance piston fixed to aforesaid rod or
piston rod. When throttle valve is opened and the block or wedge withdrawn by the
rod thence allowing rod or piston rod to act on crosshead. Crosshead on levers through
links and levers on slide valve.

page_text: On balance cylinder is placed a small drain cock behind piston leading to L.P. steam
chest or condenser.
2nd. Pins to be of iron or steel fixed or moveable. Links to be iron or steel
bushed with steel brass, phosfor bronze, or other metal to be adjustable by cotters,
bolts and nuts or otherwise or non-adjustable.
Levers and crosshead to be of iron or steel wrought or cast. Where apparatus is
used in water to be of gun metal, brass or phosfor bronze.
3rd. Said apparatus to be applied to a slide valve of any description to ease or
minimise friction for steam water or any other engine.
Slide valve not claimed, only apparatus in connection therewith.
Dated this 12th day of October 1889.
PETER WRIGHT,
4, Mariners' Cottages, South Shields, 1st Class Marine Engineer.
COMPLETE SPECIFICATION.
Improvements relating to Steam, Water, or Motive Engine Slide
Valves.
I PETER WRIGHT, 20 Eleanor Street South Shields, 1st Class Marine Engineer,
"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::
'This invention relates to apparatus to be connected with the slide valve chest of
steam water or other motive power engines for the purpose of easing the frictional
contact of the slide valve with the cylinder face.
The apparatus may act automatically and so tend to separate the slide valve from
'the cylinder face the more as the pressure at which the engine is worked increases
and less in proportion as it decreases; or the automatic arrangement may be dispensed
with and the tendency to separate the slide valve from the cylinder face may be
regulated periodically by hand as required according to the varying pressures at
which the engine may be worked; or the two arrangements may be combined so that
the action may be automatically controlled and may be further regulated by hand if
desired.
In order that the slide valve may not be forced or drawn from its seating when the
pressure in the slide valve chest is reduced after closing the throttle valve of the
engine, I provide a system of adjustable wedges acted upon by an adjustable rod
obtaining its motion from that of the throttle valve. By this means when the throttle
valve is closed the valve relieving apparatus is locked and the slide valve is therefore
maintained in close contact with the cylinder face. The throttle valve is bowever
capable of partially opening before the system of wedges is disturbed, as occurs by
the further movement of the throttle valve, and thus the valve chest is recharged to
the required pressure before the valve relieving apparatus is allowed to come into
action again.
In the accompanying drawings in all the figures of which the same part is indicated
by like reference letters
Figure 1 is a sectional elevation of the slide valve chest provided with the valve
relieving apparatus arranged to be automatically controlled or periodically.regulated
'by band.
Figure 2 is a similar sectional view showing the valve relieving apparatus 'arranged
to be periodically regulated by hand only.
Figure 3 is a plan of the slide valve chest partly in section its cover with its
attachments being removed.
Figure 4 is an end view of Figure 1 with details of the wedges L'W and A W´in
plan and section and of the bow B in plan, section, and elevation.
Figures 5, 6 and 7 are respectively a sectional elevation, a plan and an end view

page_text: of similar apparatus with the addition of bell crank levers consequent upon placing
the automatic balance cylinder of the valve relieving apparatus on the top or end of
the valve chest in a line parallel with the traverse of the slide valve.
The slide valve SV is swung by pins placed centrally at each end of the slide
valve and engaging with a pair of levers L L connected at one end with movable
links LL' capable of vibrating upon a fixed pin in the side of the valve chest or in
an independent frame made to fit within the valve chest. The levers L L are connected
at their other ends by another pair of links LL2 with a movable crosshead CH
spanning across the valve chest, working in suitable guides CH G fitted to the side of
the valve chest, or upon the independent frame hereinbefore mentioned, to engage each
end of the crosshead. The links LL2 hang in a direction opposite to that of the
links LL' to suspend the levers L L in the manner adopted in the well known parallel
notion. The crosshead CH is connected with a piston rod PR when the automatic
arrangement is adapted or with a hand rod HR when the apparatus will be
controlled entirely by hand. The piston rod PR or hand rod HR as the case
may be passes through a gland on the cover of the automatic balance cylinder A B C
or upon the valve chest cover. The connection of the piston rod PR or hand
rod HR with the crosshead CH is made by means of a double eye and bolt to
allow freedom of action upon the levers when the crosshead CH is drawn by the
balance piston BP or by hand pressure exerted upon the spiral spring SP by means
of the hand wheel fitted as a nut upon the piston rod PR or hand rod HR as the
case may be. The washers W W are placed one at each end of the spiral spring S P
to facilitate the movement of the hand wheel which may be readily turned in either
direction to act as a nut upon the screw rod which passes through the spiral spring
and the hand wheel. Upon the piston rod PR or the hand rod HR as the case may
be I provide a check nut CN, by means of which the position of an A W may be
regulated to allow more or less play between this wedge and a lock wedge L W when
the latter is withdrawn. The lock wedge L W is governed by an adjustable rod LW
deriving motion from the throttle valve TV of the engine in a manner to close the
wedges L W and A W in contact when the throttle valve TV of the engine is closed
thus preventing the slide valve S. V. being drawn off the cylinder face by the action
of the spring S P, or in the case of a steam or other condensable fluid motor, by the action
of the spring assisted by the partial vacuum formed in the valve chest when the engine
is stopped.
The slotted hole SH shown in the engaging end of the lock wedge L W allows
the throttle valve TV to be partially opened before the lock wedge LW is withdrawn
and thus the valve chest is recharged to the required pressure before the valve relieving
apparatus is allowed to come into action again.
The lock wedge LW passes through suitable_slots in the bow piece B. The
projecting horn forming part of the bow piece B provides a guide for the lock
wedge LW.
The automatic balance cylinder ABC is provided with a drain cock DC from
which a pipe may conveniently be carried to a low pressure steam chest or condenser.
When the automatic balance cylinder A B C is placed upon the top or end of the
valve chest the movement of the piston rod PR is communicated to the valve relieving
apparatus as shown in Figures 56 and 7 by means of the bell cranks BC through
links BCL and the piston rod link P R L.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. Mounting the slide valve of a motive power engine within a swinging frame
capable of regulation to ease the frictional contact of the slide valve with the cylinder
face substantially as described.
2. The employment of a balance cylinder to control a swinging frame in which a
slide valve is carried for the purpose of easing the slide valve from contact with the
cylinder face proportionately to the pressure at which the engine is worked.

page_text: 3. In apparatus for easing the frictional contact of a slide valve with the cylinder
face, the adjustable lock wedges A W and LW controlled by the throttle valve
substantially as and for the purpose described.
1
10th
Mo 1800
AYRTON & THOMAS,
Agents for the Applicant.