CERTAIN IMPROVEMENTS IN STEAM ENGINES
Year: 1876

page_text: LETTERS PATENT to Joseph Musgrave, of the Globe Iron Works, Bolton, in the
County of Lancaster, and ADAM SMITH, of the same Place, Draughtsman, for
the Invention of "CERTAIN IMPROVEMENTS IN STEAM ENGINES."
Scaled the 23th September 1876, and dated the 10th May 1876.
PROVISIONAL SPECIFICATION left by the said Joseph Musgrave and Adam
Smith at the Office of the Commissioners of Patents on the 10th May 1870.
JOSEPH MUSGRAVE, of the Globe Iron Works, Bolton, in the County of Lancaster,
and ADAM SMITH, of the same Place, Draughtsman. "CERTAIN IMPROVEMENTS IN
STEAM ENGINES."
Our Invention consists in an improved arrangement of parts for actuating the cut-
off valves of steam engines.
The front or lifting rod is raised by a tappet as usual, and to the upper end of
this rod is jointed a steel finger the upper end of which comes in contact with the
vertical arm of an elbow lever, the horizontal arm of which is connected to the
governor. As the lifting rod rises the finger is released from the vertical arm of
the elbow lever, and the moment the finger is released the lifting rod drops by its
When
own gravity, thereby acting on the cut-off valve and shutting off the steam.
the lifting rod drops the finger falls again into its original position under the end of
the vertical arm of the elbow lever, either by its own gravity or assisted by a spring.
The position of the elbow lever is varied according to the load on the engine by
the governor in the usual manner.
The above arrangement is exceedingly simple and it may be applied with facility
to existing steam engines.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Musgrave and Adam Smith in the Great Seal Patent Office
on the 3rd November 1876.
JOSEPH MUSGRAVE, of the Globe Iron Works, Bolton, in the County of Lancaster,
"CERTAIN IMPROVEMENTS IN
and ADAM SMITH, of the same Place, Draughtsman.
STEAM ENGINES."
Our Invention consists in an improved arrangement of parts for actuating the
cut-off valves of steam engines.

page_text: The front or lifting rod is raised by a tappet as usual, and to the upper end of
this rod is jointed a steel finger, the upper end of which comes in contact with the
vertical arm of an elbow lever, the horizontal arm of which is connected to the
governor. As the lifting rod rises the finger is released from the vertical arm of
the elbow lever, and the moment the tinger is released the top part of the lifting
rod drops by its own gravity, thereby acting on the cut-off valve and shutting off
the steam. When the cam allows the bottom part of the lifting rod to drop the
finger falls again into its original position under the end of the vertical arm of
the elbow lever either by its own gravity or assisted by a spring
The position of the elbow lever is varied according to the load on the engine by
the governor in the usual manner.
The above arrangement is exceedingly simple, and it may be applied with facility
to existing steam engines.
And in order that our Invention may be full understood we will proceed to
describe the accompanying Sheet of Drawings, reference being had to the figures
and letters marked thereon.
Fig. 1 represents a vertical section of the release or cut-off apparatus as applied
on the valve spindle of double beat or Cornish valves; Fig. 2 is a front elevation;
and Fig. 3 is a sectional plan of the same.
a is a box with its bottom end cottered on the valve spindle. In this box is
the loose block b, in which is a slot hole to receive the lifter projecting from the
lifting rod which is raised by a cam or tappet as usual; is a finger with its bottom
end resting in the block b, and its top end pressing against the bottom end of the
vertical arm of the elbow lever d, which when raised by the lifter lifts the valve.
The end of the horizontal arın of the elbow lever is connected to the governor by
the rod c, and when the bottom end of the vertical arm of the elbow lever d slides
off the top end of the finger f the valve closes by its own weight. As the
governor rod e falls or rises the valve closes sooner or later, according to the speed
of the engine, the block b then comes down into its former position.
In existing engines where the space is too limited to adinit of the releasing
apparatus shewn in Fig. 1, the finger f may be dispensed with, and the elbow
leverd made in two parts, as shewn in Figs. 4, 5, and 6. In this plan the mode
of operation is exactly the same as in Fig. 1, but the construction is slightly
different. Figs. 5 and 6 shew the two parts of the lever d detached. The top
end of the block b acts in the same manner as the finger f, and raises the valve
by pressing against the bottom end of the vertical arin of the lever d, which
vibrates or slides off the corner of the block b, and the valve closes as before
described.
Fig. 7 is another modification of our improved apparatus, shewn in Fig. 1. Jn
this case it is applied in the front rod, the rod being made in two parts; the
top end of the bottom part of the rod forms the block b, on which rests the
finger f.
Fig. 8 is a front elevation of the same with the front plate removed, shewing
the two sides which form part of the square box a, in which slides the top end b of
the bottom part of the front rod; p is a small air cylinder which is introduced
when the rods are very heavy to ease their fall.
Figs. 9 and 10 represent a modification of the same apparatus as it is applied to
flat valves. This apparatus can be worked by levers or cams. The long arm of
the elbow lever d is connected to the governor as in the previous Figures. The
finger is like that shewn in Fig. 1.
Figs. 11 and 12 represent the apparatus applied in the same manner as in Figs. 9
and 10, but the lever d is shewn in two parts, as shewn in Figs. 13 and 14, and
in Figs. 5 and 6.
The above apparatus is exceedingly simple, and may be applied with facility to
existing steam engines.
Having thus fully described the nature of our said Invention, and shewn the
manner in which the same can be applied and practically carried into effect, we

page_text: claim the improved self-releasing expansion apparatus for regulating the speed of
steam engines by the direct action of the governor, and particularly the application
of the finger f, or its equivalent, acting in combination with the lever d, as shown
and described.
To witness whereof, we, the said Joseph Musgrave and Adam Smith, have
hereto set our hands and seals, this Second day of November, One
thousand eight hundred and seventy-six,
JOSEPH MUSGRAVE. (LS)
ADAM SMITH.
(L.S.)