Year: 1886

page_text: We HERMANN MOEHRING, engineer and ALBERT PFLÜGER, engineer both of'
Frankfort on the Main in the Empire of Germany do hereby declare the nature'
of this invention and in what manner the same. is to be performed, to be par-
ticularly described and ascertained in and by the following statement :-
It is well known that in order to obtain economy in the use of steam or any
elastic fluid in steam engines or motors, the steam or elastic fluid must, be cut off
when a small part of the stroke has been performed, thus allowing it to work
expansively during the remainder. That furthermore the best method of obtaining
a uniform speed of the engine under variable resistance or variable pressure of the
steam or elastic fluid, is to vary the point of cutting off, in accordance therewith,.
either by hand, or as in most cases' preferable or necessary by mechanism influenced
by a governor.
It is also necessary in many cases that the direction of the notion of the engine
can be readily reversed, as in locomotives, engines for steam vessels and other
classes of engines.
The object of our invention is to accomplish the above in a more simple and.
perfect manner than has been bitherto attained. It consists in giving a peculiarly
constructed valve, two motions, one a longitudinally backward and forward
motion, the other either a rotary oscillating. (when the face of the valve is con-
structed cylindrical) or a transverse backward and forward motion (when the valve
is made flat) the valve and cylinder baving such passages or ports and construction
that by one of its above described motions the valve performs the functions of the
ordinary slide valve in giving admission and eduction, whilst by the other it acts.
as an expansion or cut-off valve.
Our invention further consists in attaching or placing an eccentric or an eccentric
pin on its driving shaft obliquely to or at an inclination to the latter. The
eccentric in revolving will then give two motions to the eccentric-rod, one the
usual backward and forward" longitudinal motion due to the eccentricity of the
CD 0.71

page_text: •
eccentric (such as eccentrics placed on their shafts in the usual manner employed
up to now give to their rods) the other being a part of a rotation in one direction
and then again returning the amount of rotation being due to the greater or less
inclination of the eccentric or eccentric pin to its shaft, and the period when this
motion takes place relative to the period of the longitudinal motion being due to
the position of the inclination.
Our invention further consists in so constructing the eccentric or eccentric pin
and mounting it on its driving shaft that the position of its inclination can bo
readily altered either by hand or by the influence of a governor and, where
desirable, the position of the eccentric also so altered by a suitable reversing gear
that the motion of the valve becomes reversed and the engine driven in consequence
backward.
Figure 1 is a sectional view of the cylinder ports, valve, valve rod, eccentric rod,
eccentric and shaft of an engine.
Figure 2 is an end view of the eccentric with its eccentric strap or hoop and rod.
Figure 3 is a side view of the eccentric in section showing its attachment to its
shaft. Figure 4 is a side section through the valve and ports of an engine.
Figure 5 is an end view in section through the valve and cylinder valve face.
Figure 6 is a top view of a portion of the valve and Figure 7 a top view of
a portion of the vaive face of the cylinder, both considered as if unrolled or laid
out flat. Figure 8 is a section through the eccentric and its attachments to a
governor and section through latter showing a manner of varying position of the
inclination of the eccentric by means of a governor. Figure 9 is an end view, the
governor attachments being removed. Figure. 10 shows a sectional top view of
the eccentric with a reversing gear attached; Figure 11 a side view of the same
and Figure 12 an end view of the eccentric and its shaft to illustrate the two
positions for forward and reverse motion of the engine. Figure 13 is a section
and Figure 14 a top view of the valve, when constructed with a flat instead of a
curved face. Figure 15 is a partly sectional and Figure 16 an end view of the
arrangement for giving the two movements to an eccentric rod, when it is
preferred to use an eccentric pin or crank pin as an equivalent for, or instead of,
an eccentric, and showing moreover a manner of altering the position of the
inclination of said eccentric pin by means of a governor..
Similar letters refer to similar parts throughout the several views.
In Figures 1, 4 and 5, C represents a steam cylinder with the usual steam
passages, and exhaust or eduction port ². Its valve face (see also Figure 7)
has furthermore the passages d. d. d. communicating at their ends respectively
with the channel ways h. . which latter are open to the steam chest E. It has
furthermore the depressions or cavities f. f. f. f. This valve face is represented
curved being a segment of a cylinder of which the centre line corresponds with the
centre line of the valve rod D, and the valve face of the valve V is made to
correspond and fit exactly thereto. These valve faces may be however. made flat
instead of cylindrical as we shall describe further on.
The valve V has on its face the transverse covered passages or cavities a and b. b.,
also on each side a number of longitudinal covered passages or cavities c. c. c. c.
which communicate with bb and also a number of passages e. e. e. through the
valve.
The valve receives as already mentioned two motions, the one being the usual
longitudinal backward and forward motion of a slide valve, the other being, when
the valve face is curved or cylindrical, a partial revolution and a return motion
(oscillation) and when the valve is constructed with a flat surface, being a back-
ward and forward motion transverse to the longitudinal motion of the valve.
The valve being in the position as shown by the drawings it is apparent that
steam admitted into the steam chest E can freely pass through the passages h. d. c.
and b. and also through e. f. c. and b, on one side of the valve to the passage.r and
thence to the forward end of the cylinder; the steam from the other end of the

page_text: cylinder escaping freely through the passage r¹ to the cavity a of the valve and
thence to the exhaust or eduction passage r³.
The described passages being the same on both sides of the valve and cylinder
valve face, when the valve is moved forward the steam will in. a similar manner
be admitted to the back end of the cylinder through passage whilst it escapes
from the forward end through passage to the eduction port 2. Thus if the
valve were moved merely longitudinally backward and forward as usual in an
ordinary slide valve, it would distribute the steam and change its admission to,
and eduction from, the two ends of. the cylinder in the usual manner in which
slide valves act, but as mentioned above we give the valve another motion
transverse to the longitudinal one. This motion closes the passages d. c. b. and e.
f. c. b. thus cutting off the admission of steam, whilst it does not interfere with the
free discharge of the steam from the other end of the steam cylinder, and moreover
the period at which this motion. cuts off the admission of steam relative to the
position of the piston of the engine, can be made fixed or variable either by hand
or by the influence of a governor as will be shown further on.
We have found that by this construction of the valve and particularly by giving
it the two motions described, we obtain a very free, admission and eduction of
steam and a very rapid cutting off of the same the period of which is easily
adjusted or controlled.
We also avoid the well known disadvantages resulting from the employment of
a valve with merely one motion and consequently imperfect action or of a number
of valves involving great complication and consequent liability to disarrangement
and repair.
It is obvious that we could increase or decrease the number of the passages cc c,
dd d, e, e, e and fff; slow running engines not requiring large passages may be.
made with less, whilst engines with high speed of piston should have an ample
number to give sufficient area for the rapid passage of steam to the cylinder,
without being obliged to make the passages of large size and necessitating thereby
an inconveniently large motion to the valve. We have mentioned that the valve
and cylinder faces may be made flat instead of cylindrical. This modification is
clearly shown by Figures 13 and 14 wherein we have also shown a method of
giving the transverse motion by means of the toothed sectors xx working in the
racks yy. In engines with long stroke where it is desirable to shorten the
admission passages and ¹ to the cylinder two valves connected together so that
they are near the ends of the cylinder may be used in the usual and well known
manner in which this is done with the usual slide valves.
We have described above that the longitudinal motion of our valve performs
certain functions, whilst the transverse or oscillating motion performs others; it is
obvious that we can reciprocally substitute these motions one for the other, the
position and direction of the steam passages in the valve faces being modified
accordingly.
Referring now to the second part of our invention it will be seen on Figures 1, 2
and 3 that we do not place or mount our eccentric on its driving shaft in the
manner hitherto done, but at an inclination or obliquely to the same. A represents
the eccentric, B is the eccentric rod, the fork of which is attached to the eccentric
hoop by hinges l. l.
The line M, N, shows the inclination of the eccentric to the shaft. Where it is
merely desirable that the degree of expansion with which the engine is to work be
fixed or invariable, the eccentric can be fixed or keyed fast to the shaft at the
proper inclination and in the proper position, and the shaft on being revolved will
give the two motions to the eccentric rod already described, the one a longitudinal
motion being due to the eccentricity of the eccentric, and the other being the,part
of a rotation and return motion or oscillation, due to the inclination of the
eccentric to its shaft and the relative periods to one another at which these
motions take place, will depend on the position of the inclination of the eccentric.

page_text: These motions being conveyed by the eccentric rod B and valve rod D to the
valve V will give the latter the proper movements which we have already described
in this specification.
But where it is desirable as in nearly all cases, to have the degree of expansion
variable the eccentric is not rigidly fast on its shaft, but mounted so that the
position of its inclination can be readily changed or altered; a mode of doing this
is the following:-
Figures 2 and 3 show two pins or trunnions m m fastened to the shaft at a
proper angle to the same and on these the eccentric is swung. The angle which
the line passing through the centre line of the trunnions makes with the centre
line of the shaft is thus fixed or invariable, but by turning the eccentric on the
trunnions the position of its inclination is changed. This change however produces
a change of the relative periods of the two motions or in other words, the
⚫ transverse or oscillating motion will commence sooner or later relatively to the
longitudinal motion, according to the direction in which the eccentric is turned on
its trunnions m m.
These motions communicated to the valve, will cause a sooner or later cutting
off of the steam, and consequently its greater or less degree of expansion in the
cylinder, whilst the lead of the valve and the eduction remains constant and
uninterfered with.
From the above it will be readily seen that by attaching to any part of the
eccentric (for example g) an appliance for moving it on its trunnions m m either
by hand or by the influence of a governor we accomplish a variable expansion
gear, variable by hand or by a governor.
In Figures 8 and 9 another mode of constructing and mounting our eccentric on
its shaft, and connecting it to a governor is shown.
The governor, in this instance, is of the kind wherein weights hung on pins on
the face of a wheel R are impelled outwards towards the periphery by their centri-
fugal force, which latter is controlled according to the speed desired by suitable
springs. By reference to Figure 16 the construction of this governor is more easily
seen, T, T, are the weights a part of which are prolonged to form the toothed
segments u u which gear into or with the pinion t.
In Figure 8 this pinion t t is shown attached to or forming part of an eccentric
wheel or disc W, mounted on the shaft S so that it can revolve on the same.
The face of this eccentric W is inclined to or forms an angle with the shaft S and
its periphery is is bevelled or conical and fits to the similarly formed portion w. w. of
the eccentric A which in this case is mounted on a spherically formed portion S³
of the shaft S. A pin p working in the slot s prevents the eccentric A from
turning on the shaft but does not prevent other motion, so that A would be free
to change its position of inclination if it were not held or controlled by the position
of W. But as we have described above, the pinion is attached to or forms part
of W, and gears into the toothed segments u u of the weights T, T, therefore any
movement of these weights on their pins. or pivots, will be communicated to W
causing it to move around the shaft.
It is manifest that such a movement of W will change the position of the
inclination of the eccentric A, and we have shown above that such a change will
cause a corresponding change in the relative periods of the two motions produced
by the eccentric, one to the other, and this change will cause the valve to cut off
the steam sooner or later as the case may be.
The weights are so adjusted, and their centrifugal force for any desired normal
or constant speed 80 counterbalanced by springs of suitable tension that, at the
normal speed of the engine they occupy a position between the extremes of their
motion towards the periphery and towards the centre of the wheel to which they
are attached, and our eccentric is mounted on the shaft at such an inclination
and in such a position of the same, that our valve will cut off the steam at the
point or period when the desired proportion of the stroke of the engine has been
accomplished.
+

page_text: Should the engine accellerate its speed, the greater centrifugal force of the
weights created thereby, will move them outwards, causing thereby a rotative
motion of the pinion t and consequently of the eccentric wheel or disc W. This
movement of W changes the position of the angle of the eccentric A and causes
the proper motion of the valve to take place sooner, thus cutting off the steam,
when a less proportion of the stroke has been performed. The reverse of this takes
place if the engine diminishes its speed, the centrifugal force of the weights being
then less, the springs will force them to move inwards reversing the motion of W
just described and changing the position of the inclination of the eccentric A so
that the valve will cut off the steam at a later period, or when a greater proportion
of the stroke has taken place.
The form or kind of governor may be any other than the one we have described.
Any governor which will turn the disc W in the proper direction when its speed
is accellerated, and reverse this motion when its speed is diminished may be
employed.
We have mentioned that by employing a suitable reversing gear the position of
our eccentric can be readily altered so that the engine may be driven forwards or
backwards as desired.
Figures 10, 11 and 12 show a proper arrangement for this purpose.
The shaft S is flattened on two opposite sides as shown in Figure 12.
The eccentric having its proper angle to the shaft as shown in Figure 10 and
having its hub of a suitable shape, as shown in Figure 11 is mounted on this
flattened portion of the shaft, so that its position can be changed by the action of
the double armed lever H which turns on its fulcrum L. By moving the hub or
sleeve K on the shaft by means of the lever K and its screw and hand wheel K³
and K the link I will communicate the motion to the double armed lever H, which
being connected with the eccentric, will change the position of the centre of the
eccentric, its inclination and the position of the same. Supposing now that when
the centre of the eccentric is at the point marked O Figure 12 the engine would
go ahead, then by moving the levers by the hand wheel towards the centre line of
their movement, the centre of the eccentric will be so moved that the valve will
cut off the steam shorter and shorter until the centre of the eccentric arrives at the
centre line of the engine when the steam will be cut off altogether and the engine
brought to stop. On continuing the motion the centre of the eccentric will proceed
towards the point 0¹ the engine will change its direction and go backwards, and
the cut off motion of the valve will take place later and later as the movement
progresses.
We have mentioned that where we prefer to use an eccentric pin instead of an
eccentric in carrying out our invention; we can readily do so. Figure 15 shows
this very clearly. Z is the eccentric pin the axial line of which is inclined to the
axial line of the shaft just as we have described is the case with our eccentric.
This eccentric pin is fastened to or forms a part of the small shaft the axis of
which is parallel to the axis of the shaft, but which has the suitable eccentricity to
give the longitudinal motion desired to the rod B. The amount of inclination of
the pin Z is determined by the amount of the other motion required as we have
described whilst explaining our eccentric. The shaft passes through shaft S, and
has attached to it the pinion t. This pinion t being turned will alter the position
of the inclination of the pin Z and cause a corresponding change in the relative
periods of the two motions, one to the other, which the pin gives to the rod B, as
we have also explained in describing the action of the eccentric.
We remark that where, in this specification we have spoken of steam or steam
engines, we do not limit our invention merely thereto.
Our invention applies also to all engines or motors using any elastic fluid, air
or gas, in the same manner as steam engines use steam. We also remark that the
shaft S on which our eccentric or eccentric pin is placed is not necessarily the
main shaft of the engine or motor, as where it is desirable it may be placed on a
secondary or supplimentary shaft.

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim is :-
1. A valve having such passages and ports and two motions at right angles to
each other imparted thereto by a single valve rod, a single eccentric rod and a
single eccentric, that by one motion it performs the functions of the simple slide
valve in giving admission to and eduction from the cylinder of an engine using
steam or any elastic fluid, gas or air, whilst by the other motion it acts as an
expansion or cut-off valve substantially as described.
2. An eccentric or an eccentric pin placed or mounted on its driving shaft at an
inclination to the same, substantially as and for the purpose described.
3. So constructing and mounting an eccentric or an eccentric pin, inclined to its
shaft, on the same, that the position of the inclination can be readily altered by
hand or by a governor, substantially as and for the purpose described.
4. So constructing and mounting an eccentric, or an eccentric pin, inclined to its
shaft on the same, that its positions can be readily changed by a reverse gear
substantially as and for the purpose described.
5. A cylinder valve face having besides admission and eduction ports, a number
of passages communicating with the steam chest and also a number of cavities or
depressions substantially as and for the purpose described.
6. The combination of a valve seat provided with steam and exhaust ports, and
with cavities f and passages d a slide valve having transverse covered passages a
and b and longitudinal passages c, and e and mechanism communicating longi-
tudinal and transverse movements to the said slide valve substantially as and for
the purpose set forth.
7. The combination of a slide valve, a revolving shaft an eccentric disc or pin
revolving with the said shaft and mounted at an inclination to the same, and a rod
pivotally connected to the said eccentric disc or pin, and to the slide valve, so that
the said valve receives longitudinal and transverse movements, substantially as
and for the purpose set forth.
8. The combination of a valve seat, provided with steam and exhaust ports and
with cavities and passages d, a slide valve having transverse covered passages a
and b and longitudinal passages cand e a revolving shaft, an eccentric disc or pin
revolving with the said shaft and mounted at an inclination to the same, and a rod
pivotally connected to the said eccentric disc or pin and to the slide valve so that
the said valve receives longitudinal and transverse movements substantially as and
for the purpose set forth.
9. The combination of a valve gear of a revolving shaft having trunnions
projecting from it at an inclination to its, axis, and an eccentric pivoted on the
said trunnions and adapted to transmit a longitudinal and an adjustable transverse
movement to the valve, substantially as and for the purpose set forth.
10. The combination in a valve gear, of a revolving shaft, an eccentric mounted
on the said shaft at an inclination to its axis, and a pin connecting the eccentric
with the shaft, so that the position of the inclination of the eccentric to the axis of
the shaft may be varied, substantially as and for the purpose set forth.
11. The combination of a slide valve, a revolving shaft, an eccentric mounted on
the said shaft at an inclination to its axis, a pin connecting the eccentric with the
shaft so that the position of the inclination of the eccentric to the axis of the
shaft may be varied, a rod pivotally connected to the eccentric and to the slide
valve so that the said valve receives transverse and longitudinal movements from
the eccentric, and a speed governor connected to the eccentric for automatically
varying the position of its inclination, and the transverse movement of the valve,
substantially as and for the purpose set forth..
12. The combination of a slide valve, a revolving shaft provided with the
spherical portion S¹ and slot S, and eccent: c mounted on the said spherical portion
at an inclination to the axis of the shaft and provided with the conical bevelled
face W, the pin, p, connecting the eccentric, with the slot in the shaft, a rod

page_text: pivotally connected to the eccentric and to the slide valve, the eccentric disc, W,
having the concentric pinion, t, secured to it and a speed governor, connected to the
said concentric pinion for automatically varying the position of the inclination of
the eccentric, and the transverse movement of the valve without altering its
longitudinal movement substantially as and for the purpose set forth.
13. The combination in a valve gear of a revolving shaft, an eccentric mounted
on the shaft at an inclination to its axis, and adapted to transmit longitudinal and
transverse movements to the valve, and a rocking lever pivotally connected to the
eccentric, for changing the position of its centre and its inclination so that the
direction of the movements transmitted by, it to the valve may be reversed,
substantially as and for the purpose set forth.