provements in Means for Working the Valves and Controlling the Speed of Motive Power Engines.
Year: 1896

page_text: Date of Application, 3rd July, 1896
Complete Specification Left, 5th Apr., 1897-Accepted, 12th June, 1897
PROVISIONAL SPECIFICATION
Improvements in Means for Working the Valves and Controlling
the Speed of Motive Power Engines.
ANDERSON
We JÖRGEN BJÖRNSTAD, Engineer and EASTON
& GOOLDEN
LIMITED both of Erith Iron Works Erith Kent do hereby declare the nature of this
invention to be as follows:-
The object of this invention is to provide improved mechanism. for working the
valves on motive power engines more especially "Corliss valves" which combines
simplicity of construction, minimum wear and tear, easy means for automatically
varying the cut off and reduced weight of the moving parts, thus admitting
of a greater number of revolutions of the engine than is usual' with sneh gears.
According to this invention the valve at each end of the cylinder is connected
through a lever arm and a connecting link to a piston working in a cylinder or
dash pot. The piston has a spring on one side which tends to shut the valve while
the cylinder on the other side of the piston forms an air buffer to prevent knocking
or jarring occurring when the spring sends the piston. towards the cover.
or towards the end of the cylinder are small, holes. formed. so. that the resistance
against the spring is increased towards the end of the stroke which causes the piston
(and consequently also the valve) to travel quickly until the valve is shut and then
move slowly up against the cover of the dash pot.
Near to
On the top of the dash pot is, a boss which forms a fulcrum for a double lever the
lower end of which is connected to and oscillated by an eccentric mounted on the
crank shaft of the engine. From points on the said double lever level with the centre.
line of the dash pot run two side links connected to a. crosshead which slides. on the
links already described connecting the valve and dash pot piston.
A flat spring with a catch at its outer end is fixed. to the under side of this
crosshead directly underneath the centre line of the first named connecting link and
extends beyond the end bearing, of the link working on. the pin of the valve lever
arm. The end of this bearing is provided with a hardened steel catch. which works
against the catch on the spring already described..
The same bearing is also provided with a projection on its outer end above the
catch which fornis a fulcrum for a small tripping lever worked from the
governor..
One end of this lever is placed in. different positions by the governor and as the
dash pot connecting link catches and the valve moves towards the centre line of
the cylinder this tripping lever is moved relatively to the catches and when the lower
part of the lever comes into a vertical position it depresses the spring with its catch
below the catch on the bearing and thus allows the spring behind the dash pot piston
to push the valve back and close it..
At the next stroke the eccentric rod moves the spring outwards and when its catch
passes the catch on the bearing it springs up and on. the next return stroke pulls the
bearing and the valve with it until at a certain position. it. again.is disengaged by the
tripping lever worked by the governor.
The tripping levers. situated one at each end of the cylinder are each worked from
a lever mounted above the centre of the dashpot, the latter lever being, connected to
the governor by a link. On the end of the pin on which this lever oscillates. is

page_text: fixed a pointer travelling over a scale which shows at a glance the exact point at which
the steam is cut off.
In the aforesaid valve gear each supply valve is supposed to be worked by
mechanism such as herein before described while the exhaust valves are worked in
the ordinary manner, but the invention is not limited to the precise details given.
The mechanism described can be used for flat slide valves, grid valves, or double beat
valves by connecting the end bearing by suitable levers or links to the respective
valves.
Dated this 3rd day of July 1896
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Means for Working the Valves and Controlling
the Speed of Motive Power Engines.
We, JÖRGEN BJÖRNSTAD, Engineer, and EASTON, ANDERSON AND GOOLDEN
LIMITED, both of Erith Iron Works, Erith, Kent, 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 object of this invention is to provide improved mechanism for working the
valves of motive power engines, more especially "Corliss valves," which mechanism
combines simplicity of construction; minimum wear and tear, and easy means for
automatically varying the cut off and reduced weight of the moving parts, thus
admitting of a greater number of revolutions, of the engine than is usual with such
gears.
We will describe the invention with reference to the accompanying drawings of
which
Figure 1 is a side elevation of a steam cylinder having Corliss valves combined
with our improved controlling mechanism, which is shewn partly in section, Figure 2
is a transverse section of the same.
Figure 3 is a detail in side elevation, and partial section, of a modification of the
mechanism,
The invention is of course not limited to the precise details illustrated.
According to this invention each of the valves A at the respective ends of the
cylinder B is connected, through a lever arm C, and a connecting link D, to a
piston E both these pistons working in a cylinder or dash pot F. The pistons E
a spring G between them so as to act on one side of each of the said pistons
the said spring tending to shut the valves, while air contained in the space in the
cylinder or dash-pot on the other side of each piston forms a buffer to prevent knocking,
or jarring, occurring when the spring sends the pistons towards the covers. Near to,
or towards, each end of the cylinder or dash-pot F are small holes H formed for the
passage of air so that the resistance against the spring is increased towards the end
of the stroke which causes each piston (and consequently also the valves) to travel
quickly until the valve is shut and then move slowly up to the cover of the cylinder or
dash-pot F.
On the top of the cylinder or dash pot F is a boss or bracket I which carries a
fulcrum for a double lever, or arms, K, the lower ends of which are connected together
by a tie-rod K' the said double lever being oscillated from the crank-shaft of the
engine by an eccentric, or the like, connected to the double lever tie-rod K' at k.
From points 2 on the said double lever K in the same horizontal plane as the centre
line of the dash-pot F extend two pairs of side links M, respectively connected at

page_text: their other ends to crossheads N, which slide on the links D connecting the valves and
dashpot-pistons E.
A flat spring O, with a catch o at its outer end, is fixed to the under side of each
of the crossheads N, underneath the connecting link D, and extends beyond the end
bearing d of the link working on the pin a² of the valve lever arm C. The end of
each bearing d is provided with a hardened steel catch which works against the
hardened steel surface carried by the catch o on the spring O.
Each bearing d is also provided with a projection d on its outer end above the
catch which projection forms a fulcrum for a tripping lever e worked from the
governor.
Each levere is turned on its fulcrum into different positions by the governor
through the rod R and connections R' as shewn and, in each case, as the dashpot
connecting link catch b and the valve arm C move towards the centre line of the
cylinder B, the tripping lever e is moved relatively to the catches 6 and o and, when
the lower part of the lever comes into a vertical position, it depresses the spring O
with its catch o below the catch b on the bearing d, and thus allows the spring G
between the dashpot pistons E, to move the valve back and close it.
At the next stroke the eccentric rod P moves the crosshead N and spring O
outwards and, when its catch o passes the catch on the bearing d, it springs up
and, on the next return stroke, pulls the bearing and the valve with it until, at a
certain position, it again is disengaged by the tripping lever worked by the governor.
The tripping levers e, situated one at each end of the cylinder, are worked from a
lever p mounted in brackets Q above the centre of the dash-pot, the lever p being
connected to the governor by the link, or rod, R. On the end of the pin which carries
the lever is fixed a pointer q, travelling over a scale r, which shews at a glance
the exact point at which the steam is cut off.
Instead of the catches being carried on blade springs O as shewn in Figure 1,
the arrangement illustrated in Figure 3 may be employed, consisting of a bracket,
or arm, S, secured to the cross-head N, and having hinged thereto an arm S²,
carrying the catch o.
One end of a helical spring O contained in a thimble T bears on the underside
of the arm S the thimble being carried by the bracket, or arm, S, and being
provided with an adjusting screw t by which the power of the spring O can be
regulated as required.
In the aforesaid valve-gear each valve A is worked by mechanism such as
herein before described. The exhaust valves A2 can be worked in the ordinary
manner.
The mechanism described can be used for flat slide valves, grid valves, or double
beat valves, by connecting the end bearings d, by suitable levers, or links, to the
respective valves.
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 :-
The combination and arrangements of parts constituting the improved means
for working the valves, and controlling the speed of, motive power engines;
substantially as herein before described, and illustrated by the accompanying drawings.
Dated this 5th day of Auril 1897.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.