Year: 1898

page_text: I, JOHANN STUMPF, of 19, Lessing Strasse, of Berlin, Kingdom of Prussia, German
Empire, Profesor, do hereby declare the nature of this invention to be as follows:-
This invention relates to Corliss-gear for steam engines and has for its object
various improvements in the construction of the same.
Corliss gear for steam-engines as hitherto employed, possesses various disadvan-
tages. The oscillating driving disc (as usually mounted), only allows steam-fillings
of 0-0.4, .e. very small in extent.
Moreover, in the Corliss-gear hitherto used the slides are usually kept con-
stantly moving and mostly under a full load. In consequence of this, the known
humming of the slides takes place, more especially in the case of the modern
high-pressure engines.
Furthermore the lubrication also occasions peculiar difficulties, so that, should
a good lubricating oil not be used, frequent stoppages or the like may be looked
for, by, or in consequence of the bearings running hot. Furthermore the journal-
ling of the oscillating driving discs is difficult, as the heat produced by the steam-
mantle may also quickly cause the parts to run hot and bind.
The Corliss-gear forming the subject of this invention has the object of obviating
these disadvantages; the characteristic feature of the invention residing in the
employment of an especial organ, a mechanism, or actuating device for the slides,
said device revolving or moving in a circular, elliptic, or in any case, in a closed
path.
When employing my improved mechanism, every optional filling of steam from
0, to nearly full can be obtained. Furthermore my improved driving-device does
not at all come into contact with the cylinder, so that an injurious overheating
cannot possibly take place. Besides this the device can conveniently be so
arranged, that the slides are moved with almost no load at all upon them.
My improved device is advantageously actuated by an eccentric on the machine.
shaft with the aid of an eccentric rod guided at a suitable point either in a straight
direction, or,.
the said eccentric rod may be supported by another rod or the like.
If the before mentioned eccentric rod, be arranged to travel in a straight path,
the end of the same opposite to the eccentric, will then perform an exactly circular
path. For the practical carrying out of my invention however it suffices to
support the eccentric rod approximately at its centre, by a guiding rod, so that the
free end of the slide actuating mechanism would then describe a curve in the form
of an ellipse.
One form of carrying out my invention and also modifications are shown in the
accompanying drawings, in which similar views denote similar parts.
The engine shown in side-view in Figure 1 is so arranged, that the movement

page_text: of the eccentric 6, keyed to the shaft, is conveyed by the rod e to a cross-head d,
which is so actuated at the side of the cylinder e, that its several points describe
the approximately circular path shown in Figure 2.
A guiding-rod c¹ is pivoted at 2 upon the machine-frame, and supports at c³, the
eccentric rod c approximately at its centre, Figure 1.
The cross-head d carries at its lower end two fixed studs d (Figure 2) which
engage with the driving rod g of the outlet slides h. The rods i of the inlet-slide k
are not rigidly connected to the cross-head d, but have their free ends suspended
by rods from the crank level 1, said crank-lever being connected by the rod 12
with the governor.
The free ends of the rods also carry or are provided with, slanting circular-
bearing-surfaces ¹ corresponding to the slanting-surfaces 2 on the cross-head.
The modus operandi of this mechanism is at once apparent.
The outlet slides are always regularly actuated from the cross-head, whilst the
extent of the inlet-slide movement, varies according to the length of the time during
which the bearing-surfaces 2 of the cross-head act upon the corresponding surfaces i¹
of the driving-rod i, the height of the latter being influenced by the governor.
The inlet valves are opened by the contact-surfaces of the cross-head; the same
are closed under the influence of air-buffers m, which come into action, as soon as
the rods are free from the cross-head. The air-buffers are connected by rods m¹
with the inlet-slide-cranks.
In the case of cylinders not influenced by the action of the governor, as for
instance, low-pressure cylinders of compound and treble expansion steam-engines,
the driving-rods i instead of being suspended at their ends from the crank-lever
actuated by the governor, may be directly connected with the pin in a similar
manner as is the case with regard to the outlet-slides. (Figure 4.)
It has been herein before mentioned, that the slides in my improved construction
are moved almost entirely free of any load, this being a factor of especial
importance.
The slide movement of the diagram shown in Figure 6 is as follows;
The outlet slide is set in motion at A and again released at B; the short
distances A A¹ and B B¹ represent the time occupied in running over the lap, said
lap, as is apparent being necessary to keep the slides steam-tight.
During the transcribing of the lines of the diagram of B to A the outlet slide remains
at a stand-still, that is to say, at the time, when the same is at full load. From
A to B the slide however, has no load, the movement of the slides only taking
place during the formation of this portion of the curve.
The inlet slide comes into action at the point C of the diagram. The
distance C C serves to run through the lap; at 1) the shunting out takes place,
and up to 11 the lap is again run through.
From DC the inlet valve is again in a position of rest.
I have therefore attained, that both the inlet and outlet slides are only moved
or actuated when bearing no load, whilst by the normal Corliss gear, almost the
entire or at any rate a very large portion of the said movement takes place with
great differences of pressure, over and under, the slide.
In my improved construction, I have succeeded in obtaining an unvarying and
equal pressure or tension (or approximately so) on both sides of the slides.
Furthermore by means of my improved gear another important advantage is
attained viz., that the angle of lead of the outlet valve, can with ease be regulated
for the purpose of altering the compression.
Figure 2 shows two further recesses d² on the cross-head , so that when the
studs d¹ of the driving rods g for the outlet slides, are placed within said recesses d²,
the angle of lead is hereby increased to the extent of the angle ẞ.
The compression can thus be changed without any alteration in the position of
the chief or main driving eccentric having been necessary. This is very important
for engines, which are operated partly as exhaust motors, and partly with con-

page_text: densation, in connection with which motors an alteration of the compression is
consequently, for the reason above stated, desirable.
The modification shown in Figure 4 represents an alteration or another improved
method of the driving-gear of the inlet valve. The contact surfaces on the
cross-head d have here movable parts 24, arranged upon the stud ³, the said movable
parts being held concentrically to the contact surfaces i¹ or to the studs n¹ by
steerings rods n movable or sliding in recesses of the slide crank pins or studs n¹.
Figure 3 shows this modification in side view.
The mechanism is somewhat more complicated than that shown in Figures 1 & 2.
In the latter the contact surfaces ¹ and do not always come concentrically one
over the other.
I, JOHANN STUMPF, of 19, Lessing Strasse, of Berlin, Kingdom of Prussia, German
Empire, Professor, 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 Corliss-gear for steam-engines and has for its object
various improvements in the construction of the same.
Corliss-gear for steam-engines as hitherto employed, possesses various disadvan-
tages. The oscillating driving disc (as usually mounted), only allows steam-fillings
of 0, to 04, i.e. very small in extent.
Moreover, in the Corliss-gear hitherto used the slides are usually kept con-
stantly moving and mostly under a full load. In consequence of this, the known
humming of the slides takes place, more especially in the case of the modern
high-pressure engines.
Furthermore the lubrication also occasions peculiar difficulties, so that, should
a good lubricating oil not be used, frequent stoppages or the like may be looked
for, by, or in consequence of the bearings running hot. Furthermore the journal-
ing of the oscillating driving discs is difficult, as the heat produced by the steam-
mantle may also quickly cause the parts to run hot and bind.
The Corliss-gear forming the subject of this invention has the object of obviating
these disadvantages; the characteristic feature of the invention residing in the
employment of an especial organ, a mechanism, or actuating device for the slides,
said device revolving or moving in a circular, elliptic, or in any case, in a closed
path.
When employing my improved mechanism, every optional filling of steam from
0, to nearly full can be obtained. Furthermore my improved driving-device does
not at all come into contact with the cylinder, so that an injurious overheating
cannot possibly take place. Besides this, the device can conveniently be so
arranged, that the slides are moved with almost no load at all upon them.
My improved device is advantageously actuated by an eccentric on the machine-
shaft with the aid of an eccentric rod guided at a suitable point either in a straight
direction, or, the said eccentric rod may be supported by another rod or the like.

page_text: If the before mentioned eccentric rod, be arranged to travel in a straight path,
the end of the same opposite to the eccentric, will then perform an exactly circular
path. For the practical carrying out of my invention however, it suffices to
support the eccentric rod approximately at its centre, by a guiding rod, so that the
free end of the slide actuating mechanism would then describe a curve in the form
of an ellipse.
One form of carrying out my invention and also modifications are shown in the
drawings, filed with the Provisional Specification, in which similar letters denote
similar parts.
The engine shown in side-view in Figure 1 is so arranged, that the movement
of the eccentric b, keyed to the shaft, is conveyed by the rod c to a, cross-head d,
which is so actuated at the side of the cylinder e, that its several points describe
the approximately circular path shown in Figure 2..
A guiding-rod is pivoted at c³ upon the machine-frame, and supports at 3, the
eccentric rod e approximately at its centre, Figure 1.
The cross-head carries at its lower end two fixed studs d (Figure 2) which
engage with the driving rod g of the outlet slides h. The rods i of the inlet-slide k
are not rigidly connected to the cross-head d, but have their free ends suspended
by rods from the crank lever 1, said crank-lever being connected by the rod 12
with the governor.
The free ends of the rods i also carry or are provided with, slanting circular-
bearing-surfaces corresponding to the slanting-surfaces on the cross-head.
The modus operandi of this mechanism is at once apparent.
The outlet slides are always regularly-actuated from the cross-head, whilst the
extent of the inlet-slide-movement, varies according to the length of the time during
which the bearing-surfaces of the cross-head act upon the corresponding surfaces i¹
of the driving-rod i, the height of the latter being influenced by the governor.
The inlet valves are opened by the contact-surfaces of the cross-head; the same
are closed under the influence of air-buffers m, which come into action, as soon as
the rods i are free from the cross-head. The air-buffers are connected by rods m¹
with the inlet-slide-cranks.
In the case of cylinders not influenced by the action of the governor, as for
instance, low-pressure cylinders of compound and treble expansion steam-engines,
the driving-rods i instead of being suspended at their ends from the crank-lever
actuated by the governor, may be directly connected with the pin in a similar
manner as is the case with regard to the outlet-slides. (Fig. 1.)
It has been hereinbefore mentioned, that the slides in my improved construction
are moved almost entirely free of any load, this being a factor of especial
importance.
The slide movement of the diagram shown in Figure 6 is as follows:-
The outlet slide is set in motion at A and again released at B; the short
distances A A and B B represent the time occupied in running over the lap, said
lap, as is apparent being necessary to keep the slides steam-tight.
During the transcribing of the lines of the diagram of B to A the outlet slide remains
at a stand-still, that is to say, at the time, when the same is at full load. From
A to B the slide however, has no load, the movement of the slides only taking
place during the formation of this portion of the curve.
The inlet slide comes into action at the point C of the diagram. The
distance CC serves to run through the lap at 1) the shunting out takes place,
and up to D¹ the lap is again run through.
:
From DC the inlet valve is again in a position of rest.
I have therefore attained, that both the inlet and outlet slides are only moved
or actuated when bearing no load, whilst by the normal Corliss-gear, almost the
entire or at any rate a very large portion of the said movement takes place with
great differences of pressure, over and under, the slide.
In my improved conctruction, I have succeeded also in obtaining an unvarying
and equal pressure or tension (or approximately so) on both sides of the slides.

page_text: Furthermore by means of my improved gear another important advantage is
attained, viz., that the angle of lead of the outlet valve, can with ease be regulated
for the purpose of altering the compression.
Figure 2 shows two further recesses d² on the cross-head d, so that when the
studs d' of the driving rods g for the outlet slides, are placed within said recesses d³,
the angle of lead is hereby increased to the extent of the angle ẞ.
The compression can thus be changed without any alteration in the position of
the chief or main driving eccentric having been necessary. This is very important
for engines, which are operated partly as exhaust motors, and partly with con-
densation, in connection with which motors an alteration of the compression, is,
consequently, for the reason above stated, desirable.
The modification shown in Figure 4 represents an alteration or another improved
method of the driving-gear of the inlet valve. The contact surfaces on the
cross-head d have here movable parts, arranged upon the stud 23, the said movable
parts being held concentrically to the contact surfaces 23 by steering rods n. The
driving rods have extensions 5 upon which extensions, the steering rods provided
with suitable sliding sockets, are movable.
Figure 3 shows this modification in side view.
The mechanism is somewhat more complicated than that shown in Figures 1 & 2.
In the latter the contact surfaces 2 and 3 do not always come concentrically one
over the other.
Having now particularly described the nature of my said invention, and in what
manner the same is to be performed, I declare that what I claim is :-
1. An improved Corliss-gear, in which the organ actuating the slides instead of
moving to and fro, is arranged to move in a closed curve, whereby steam-fillings
from 0 to nearly 1 are obtained, and the time for the opening and closing of the
slides caused to be independent one of the other, substantially as described.
2. A modification of the Corliss gear characterized in Claim 1, in which the
slide-rods i org are actuated by a cross-head (d), which by means of an eccentric
rod guided at a suitable point, or by means of an eccentric rod (e) supported by
another rod, is caused to move in a closed curved path, substantially as described.
3. An improved Corliss-gear as characterized in Claim 1, in which the inlet
valve-rods i, from time to time, influenced by the action of the governor, come in
contact with the slanting surfaces (22) of the driving organ (d), substantially as
described.
4. A Corliss gear as characterized in Claim 1, in which for the purpose of changing
the angle of lead, and hereby also the compression, the driving-rods (g) of the outlet-
slide (h), are arranged adjustable upon the cross-head (d), substantially as
described.
Dated this 2nd day of August 1898.
GEO. THOS. HYDE,
No. 1, Broad Street Buildings, Liverpool Street, E.C.,
Agent for Applicant.