Improved Reverse and Variable Cut Off for Portable and other Engines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improved Reverse and Variable Cut Off for Portable and other
Engines.
I, JOHN ABELL, of 48, Abell Street, in the City of Toronto, in the County
of York, and the Province of Ontario, Canada, Manufacturer, do hereby declare the
nature of this invention to be as follows:-
The object of this invention is to devise a reverse and variable cut off which will
permit of the widest possible range and accuracy of cut off, which will reverse
quickly and which is simple in construction and reliable in operation, and it
consists essentially in operating the valve connecting rod from a crank pin on
a slide adjustable on a suitably driven crank disc and provided with means
whereby its position on the disk may be changed at will while the parts are in
motion, substantially as hereinafter more specifically described.
Figure 1, is a plan view of a portable engine provided with my improvements.
Figure 2, is an enlarged sectional elevation of the reverse and cut off.
Figure 3, is a perspective view of the movable sleeve.
Figure 4, is an end view of the slide and the disk on which it is movable.
In the drawings like letters of reference indicate corresponding parts in the
different figures.
A, is the valve chest of the engine, and B, the valve rod running in the guides
in the usual manner. C, is a connecting rod pivotally connected at one end with
the valve rod, and at the other journalled upon the wrist pin D, on the slide E.
This slide is dove-tailed to fit within a dove tailed groove formed in the face of
the disk F, one side of the groove being formed with an anti-friction lining
which may be removed or adjusted to take up wear. A rack G, is formed upon
The disk F, is carried by a sleeve H, suitably
the inner surface of the slide.
journalled on the top of the engine.
A gear wheel I, is also formed on or connected to the disk F, and meshes with
a gear wheel J, upon the main shaft K, of the engine. Extending through the
sleeve H, is the shaft L, having upon the one end a pinion M, meshing with the
rack G. Its other end extends out beyond the sleeve H, and has a sleeve N,
secured thereon, which sleeve is suitably journalled as indicated. The sleeve
and shaft are preferably connected by means of a set screw a so that their position
in regard to one another can be altered.
Surrounding the sleeves H, and N, is a longitudinally movable sleeve O, pro-
vided with a collar b. Surround this collar is a babbit lined shifter P,
pivotally connected with one arm of the bell crank lever Q, suitably pivoted on
the frame of the machine. The other arm of this bell crank lever is connected by
a suitable rod c with the hand lever R, by means of which the bell crank lever
may be moved as required to shift the sleeve O, and to hold it as moved.
Cut in the sleeve N, are the oppositely inclined slots d with which engage
blocks a preferably pivotally connected to the sleeves H, and N.
From the construction described it follows that by shifting the sleeve O, that

page_text: a rapid movement of rotation will be given to the shaft L, relative to the sleeve H,
and that consequently the position of the slide E, upon the face of the disk F,
will be altered as such a shifting of the slide moves its wrist pin with respect
to the centre of the disk, it is evident that the travel of the valve connecting rod
will be altered and consequently the cut off of the valve. The cut off may be
thus varied to admit live steam for the full length of the stroke, or to permit of
expansion as may be desired up to six-tenths of the stroke. As by moving the
slide the position of the wrist pin may be instantly reversed, it is evident that
the engine will be also reversed so that the operation of the engine is entirely under
control by the operator at the hand lever R.
I do not wish to confine myself to the exact construction shown, as the disk F,
might be differently driven, and different arrangements provided for shifting the
relative position of the sleeve H, and the shaft L, while the engine is in motion.
It will be seen that I have devised a very simple and effective reverse and variable
cut off which gives to the engineer the greatest possible control over the engine,
and enables him to secure the maximum amount of work from the engine in
proportion to the fuel and water used.
Improved Reverse and Variable Cut Off for Portable and other
Engines.
I, JOHN ABELL, of 48, Abell Street, in the City of Toronto, in the County
of York, and Province of Ontario, Canada, Manufacturer, 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, refer-
ence being had to the drawings accompanying my Provisional Specification filed
in connexion with this application:-
The object of this invention is to devise a reverse and variable cut off which will
permit of the widest possible range and accuracy of cut off, which will reverse
quickly and which is simple in construction and reliable in operation, and it
consists, essentially, in operating the valve connecting rod from a crank pin on
a slide adjustable on a suitably driven crank disk and provided with means
whereby its position on the disk may be changed at will while the parts are in
motion, substantially as hereinafter more specifically described and then definitely
claimed.
Figure 1, is a plan view of a portable engine provided with my improvements.
Figure 2, is an enlarged sectional elevation of the reverse and cut off.
Figure 3, is a perspective view of the movable sleeve.
Figure 4, is an end view of the slide and the disk on which it is movable.
In the drawings, like letters of reference indicate corresponding parts in the
different figures.
A, is the valve chest of the engine, and B, the valve rod running in the guides
in the usual manner. C, is a connecting rod pivotally connected at one end with
the valve rod, and at the other journalled upon the wrist pin D, on the slide E.
This slide is dove-tailed to fit within a dove-tailed groove formed in the face of
the disk F, one side of the groove being formed with an anti-friction lining

page_text: which may be removed or adjusted to take up wear. A rack U, 1s 1ormed upon
the inner surface of the slide. The disk F, is carried by a sleeve H, suitably
Journalled on the top of the engine.
A gear wheel I, is also formed on or connected to the disk F, and meshes with
a gear wheel J, upon the main shaft K, of the engine. Extending through the
sleeve H, is the shaft L, having upon the one end a pinion M, meshing with the
rack G. Its other end extends out beyond the sleeve H, and has a sleeve N,
secured thereon, which sleeve is suitably journalled as indicated. The sleeve
and shaft are preferably connected by means of a set screw a so that their position
in regard to one another can be altered.
Surrounding the sleeves H, and N, is a longitudinally movable sleeve O, pro-
vided with a collar 6. Surrounding this collar is a babbit lined shifter P,
pivotally connected with one arm of the bell crank lever Q, suitably pivoted on
the frame of the machine. The other arm of this bell crank lever is connected by
a suitable rod c with the hand lever R, by means of which the bell crank lever
may be moved as required to shift the sleeve O, and to hold it as moved.
Cut in the sleeve N, are the oppositely inclined slots & with which engage
blocks e preferably pivotally connected to the sleeves H, and N.
From the construction described it follows that by shifting the sleeve 0, that
a rapid movement of rotation will be given to the shaft L, relative to the sleeve H,
and that consequently the position of the slide E, upon the face of the disk F,
will be altered as such a shifting of the slide moves its wrist pin with respect
to the centre of the disk, it is evident that the travel of the valve connecting rod
will be altered and consequently the cut off of the valve. The cut off may be
thus varied to admit live steam for the full length of the stroke, or to permit of
expansion as may be desired up to six-tenths of the stroke. As by moving the
slide the position of the wrist pin may be instantly reversed, it is evident that
the engine will be also reversed so that the operation of the engine is entirely under
control by the operator at the hand lever R.
I do not wish to confine myself to the exact construction shown, as the disk F,
might be differently driven and different arrangements provided for shifting the
relative position of the sleeve H, and the shaft L, while the engine is in motion.
It will be seen that I have devised a very simple and effective reverse and variable
cut off which gives to the engineer the greatest possible control over the engine,
and enables him to secure the maximum amount of work from the engine in
proportion to the fuel and water used.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:--
1. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk having
guides thereon in which the said slide may move, a suitably journalled sleeve on
which the said disk is fast, means for revolving the said sleeve from some moving
part, a shaft within the sleeve, a connection between the shaft and the slide where-
by the latter may be moved by the turning of the shaft, and means for turning
the said shaft, substantially as and for the purpose specified.
2. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk
having guides thereon in which the said slide may move, a suitably journalled
sleeve on which the said disk is fast, means for revolving the said sleeve from
some moving part, a shaft within the sleeve, a pinion on the shaft, a rack on the
slide with which the said pinion engages, and means for turning the shaft, sub-
stantially as and for the purpose specified.
3. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk having
guides thereon in which the said slide may move, a suitably journalled sleeve on

page_text: which the said disc is fast, means for revolving the said sleeve from some moving
part, a shaft within the sleeve, a connection between the shaft and the slide
whereby the latter may be moved by the turning of the shaft, a sleeve secured on
the shaft at the end of the first-mentioned sleeve, a longitudinally-movable sleeve
embracing the said sleeves and provided with oppositely inclined slots engaging
the said blocks, substantially as and for the purpose specified.
4. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk having
guides thereon in which the said slide, may move, a suitably journalled sleeve on
which the said disk is fast, means for revolving the said sleeve from some moving
part, a shaft within the sleeve, a connection between the shaft and the slide
whereby the latter may be moved by the turning of the shaft, a sleeve adjustably
secured on the shaft at the end of the first-mentioned sleeve, a block projecting
from each sleeve, a longitudinally movable sleeve embracing the said sleeves and
provided with oppositely inclined slots engaging the said blocks, substantially
as and for the purpose specified.
5. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk having
guides thereon in which the said slide may move, a suitably journalled sleeve on
which the said disk is fast, means for revolving the said sleeve from some moving
párt, a shaft within the sleeve, a connection between the shaft and the slide
whereby the latter may be moved by the turning of the shaft, a sleeve secured
on the shaft at the end of the first-mentioned sleeve, a block projecting from
each sleeve, a longitudinally movable sleeve embracing the said sleeves and pro-
vided with oppositely inclined slots engaging the said blocks, a collar formed on
the said sleeve, a bell crank lever adapted to engage the said collar and means
for moving the said lever and holding it as moved, substantially as and for the
purpose specified.
6. In mechanism for the purpose described, a slide having a wrist pin thereon
on which is journalled the valve connecting rod in combination with a disk having
guides thereon in which the said slide may move, a suitably journalled sleeve
on which the said disk is fast, means for revolving the said sleeve from some
moving part a shaft within the sleeve, a pinion on the shaft, a rack on the slide
with which the said pinion engages, a sleeve secured on the shaft at the end of
the first-mentioned sleeve, a block projecting from each sleeve, a longitudinally
movable sleeve embracing the said sleeves, and provided with oppositely inclined
slots engaging the said blocks, substantially as and for the purpose specified.
7. In mechanism for the purpose described the combination of a slide having
a wrist pin thereon on which is journalled the valve connecting rod, a disk having
guides thereon in which the said slide may move, a suitably journalled sleeve on
which said disk is fast, gearing between the said sleeve and the main shaft of
the engine, a shaft within the sleeve, a connection between the shaft and the slide
whereby the latter may be moved by the turning of the shaft, a sleeve secured
on the shaft at the end of the first mentioned sleeve, a block projecting from each
sleeve, a longitudinally movable sleeve embracing the said sleeves and provided
with oppositely inclined slots engaging the said blocks, and means for adjusting
the said sleeve while the engine is in motion, substantially as and for the purpose
specified.