A NEW OR IMPROVED FORM OF AUTOMATIC EXPANSION APPARATUS FOR APPLYING TO WINDING ENGINES
Year: 1877

page_text: LETTERS PATENT to John Lloyd, of Priors Lee Hall, near Shifnal, Shropshire,
for the Invention of "A NEW OR IMPROVED FORM OF AUTOMATIC EXPANSION
APPARATUS FOR APPLYING TO WINDING ENGINES."
PROVISIONAL SPECIFICATION left by the said John Lloyd at the Office
of the Commissioners of Patents on the 26th September 1877.
JOHN LLOYD, of Priors Lee Hall, near Shifnal, Shropshire. "A. NEW OR IMPROVED
FORM OF AUTOMATIC EXPANSION APPARATUS FOR APPLYING TO WINDING
ENGINES."
According to this Invention a disc is set in motion by a shaft connected with the
drum shaft by a worm, screw, bevel gearing, or other arrangement, so that the disc
shall make one complete revolution while the drum shaft makes the requisite number
of revolutions to perform the up or down journey in the pit shaft. On each side of
the circumference of the disc a number of cut-off plates are bolted, each having a
certain amount of taper. As the disc revolves the cut-off plates are brought in
contact with catches which raise a lever connected to an equilibrium valve placed
between the steam valves of the engine cylinder; or, if a slide valve, at the back of
same, or in any other convenient position. This valve cuts off steam according to
the varying taper on the cut-off plates. One of the catches falls into gear for the up
journey, and the other catch for the down journey. Both these catches are bolted
together, and so balanced as to fall into gear automatically according as the disc
revolves. A lever works on a fixed pin, and is fitted with two stops which prevent
On the other side
the catches, when reversed by disc, from falling over too far.
of disc the taper plates are arranged with the taper running the contrary
way.
The taper in the cut-off plates can be made more or less so as to cause any desired
degree of expansion. I arrange a shaft with levers and links connected with a lever

page_text: worked by hand or foot, so that the engine man at any time may throw it out of
gear, or himself regulate the expansion by hand independently of the automatic cut-
off gear.
A balance weight is attached to the last-mentioned lever to equalize friction and
the weight of levers and rods. After the automatic cut-off gear has been thrown
out, as described above, it may be again applied during any part of journey, as the
shaft on which the disc is fixed always continues to revolve. The disc is provided
with a plain part periphery, on which the catches are caused to act without shifting
the expansion valve when the engine first starts.
The worm may be upon a shaft arranged to work into a worm wheel upon the
disc shaft.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Lloyd in the Great Seal Patent Office on the 26th March
1878.
JOHN LLOYD, of Priors Lee Hall, near Shifnal, Shropshire. "A NEW OR IMPROVED
FORM OF AUTOMATIC EXPANSION APPARATUS FOR APPLYING TO WINDING
ENGINES."
This Invention relates to a new or improved form of automatic expansion
apparatus for applying to winding engines, and will be clearly understood by the
following description with reference to the annexed 2 Sheets of Drawings.
A is a disc set in motion by shaft B, which is connected with the drum shaft by
a worm, screw, bevel gearing, or other arrangement, so that the disc A makes one
revolution or part of a revolution while the drum shaft makes the requisite number
of revolutions to perform the up or down journey in the pit shaft. On each side of
the circumference of the disc a number of cut-off plates C are bolted, varying in
length. As the disc A revolves the cut-off plates C are brought in contact with
catches E and E', which raise the lever D, which is connected to a valve F placed
between the steam and exhaust valves of the engine cylinder, where equilibrium
valves are used; or, if a slide valve, at the back of same, or in any other convenient
position. This valve F cuts off steam according to the varying length of plane on
the cut-off plates. Catch E falls into gear for the up journey and catch E for the
down journey. Both these catches, E and E¹, are bolted together, and so balanced
Lever D works
as to fall into gear automatically, according as the disc A revolves.
on a fixed pin L and is fitted with two stops, O and O', which prevent the catches
E and E', when reversed by disc A, from falling over too far. On the other side of
disc A, the plates C are arranged with the "cut-off" the contrary way.
The length of planes on the cut-off plates C can be made more or less so as to cause
any desired degree of expansion. Shaft G, with levers H and links K, are connected
with a lever worked by hand or foot, so that the engine man at any time may throw
it out of gear, or himself regulate the expansion by hand independently of the
automatic cut-off gear.
The balance weight N is attached to lever D to equalize friction and the weight
of levers and rods. After the automatic cut-off gear has been thrown out, as described
above, it may be again applied during any part of journey, as the shaft P on which

page_text: the disc A is fixed always continues to revolve. The disc is provided with a plain
part on its periphery, on which the catches are carried or slide without shifting the
expansion valve for one or more revolutions, so that there may be the full pressure
of steam on the pistons throughout the stroke for starting the load.
The worm may be upon a shaft arranged to work into a worm wheel upon the
disc shaft P.
Having now described the nature of my said Invention, and in what manner the
same is to be performed, I declare that I claim,―
First. The general arrangement and combination of parts constituting my new
improved form of automatic expansion apparatus for applying to winding engines,
as herein-before described, and substantially as shown in the annexed Drawings.
Secondly. The employment of the disc A, fitted with a number of cut-off plates C,
in combination with the catches E, E¹, and lever D, for the purposes set forth, and
as shown in the Drawings.
In witness whereof, I, the said John Lloyd, have hereunto set my hand and
seal, this Twenty-third day of March, One thousand eight hundred and
seventy-eight.