IMPROVEMENTS IN LIME AND CEMENT KILNS
Year: 1877

page_text: LETTERS PATENT to James Hall, of Wray's Horley, in the County of Surrey,
and John Medworth, of 47, Bartholomew Road, Kontish Town, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN LIME AND CEMENT
KILNS"
Scaled the 6th July 1877, and dated the 26th January 1877.
PROVISIONAL SPECIFICATION left by the said James Hall and John
Medworth at the Office of the Commissioners of Patents on the 20th January
1877
JAMES HALL, of Wray's Horley, in the County of Surrey, and JOHN MEDWORTH,
IM-
of 47, Bartholomew Road, Kentish Town, in the County of Middlesex
PROVEMENTS IN LIME AND CEMENT KILNS"
In the Specification of a former Patent granted to one of us, No 346, in the
year 1875, was described an arrangement of kiln for allowing measured quantities
In this
of lime or cement to be withdrawn from time to time from the kiln
arrangement the contents of the kiln are ordinarily supported upon a gid, below
the grid is a chamber provided at the bottom with tiap doors, the doors are
closed at the commencement of the drawing operation and the grids are drawn
back allowing the chamber to fill, afterwards the grids are replaced and the trap
doors opened to drop the measured quantity of lime o cement into a wagon
With this arrangement it is necessary to draw back the grids suddenly or the
centre of the material in the kiln will run down in the first instance instead of
dropping equally all over the kiln The lime in the kiln is therefore allowed to
drop, and is consequently broken The concussion on the doors and works below is
also great.
According to our present Invention we obviate these inconveniences by the use
The box is so mounted that its bottom can be raised
of a rising and failing box
close up to the fire-bars or grid and remain there whilst the grid 18 smoothly and
The box can
quietly withdrawn by right and left handed screws or otherwise
then be lowered at any desired speed and the contents of the kiln will descend
uniformly with it When the box has descended to the extent required the grid
is replaced and the doors at the bottom of the box are opened to drop the material
which has been withdrawn from the kiln into a wagon. The box can be raised and

page_text: lowered by chains, which also control the opening and closing of the doors To
effect this the ends of the lifting chains may be coupled by other short chains to
the two doors which form the bottom of the box When the chains are raised
they close the doors and then lift the box When the chains are lowered the box
descends until it is arrested by stops, any further lowering of the chains will then
allow the doors to open The position of the stops will govern the amount that is
withdrawn from the kiln at each withdrawal
To raise and lower the lifting chains they may be conducted over guide pulleys
to a rollei, on to which they can be wound or unwound The roller may be free to
move endwise in its bearings, so that the chains may be wound uniformly on to it
A long pinion may be employed to transmit motion to a toothed wheel on the
roller so as always to remain in gear, notwithstanding that the roller moves
endwiso
In place, also, of forming the hood of the kiln in two parts which can be moved
away sidewise to allow of feeding in limestone or material we make the hood in
one piece, which can be lifted up clear of the top of the kiln, and we form a
cncular line of railway around the upper part of the kiln On this circular railway
we place a trolly, on to which a truck carrying the material to be fed into the
furnace can be iun The trolly can then be moved round on the cucular railway
to either side of the kiln to allow of the contents of the truck being discharged into
the kiln from any desired point By this means uniformity in the charging of the
kiln can readily be obtained
In place of the above arrangement we may make the hood itself with hoppers
(for limestone and fuel respectively), the whole of which can be made to revolve
and mechanically discharge their contents
"
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Jaines Hall and John Medworth in the Great Seal Patent Office on
the 26th July 1877
"IM-
JAMES HALL, of Wiay's Horley, in the County of Surrey, and JOHN MEDWORTH,
of 47, Bartholomew Road, Kentish Town, in the County of Middlesex
PROVEMENTS IN LIME AND CEMENT KILNS"
In the Specification of a former Patent granted to one of us, No 346, in the
year 1875, was described an arrangement of kiln for allowing measured qualities
of lime or cement to be withdrawn from time to time from the kiln In this
anangement the contents of the kiln are ordinarily supported upon a grid, below
the gid is a chamber provided at the bottom with trap doors, the doors are
closed at the commencement of the drawing operation and the grids are drawn
back allowing the chamber to fill, afterwards the guds are replaced and the tiap
doors opened to drop the measured quantity of lune o cement into a wagon
With this arrangement it is necessary to draw back the grids suddenly or the
centre of the material in the kiln will run down in the first instance instead of
dropping equally all over the kiln The lime in the kiln is therefore allowed to
drop, and is consequently broken The concussion on the doors and works below is
also great
According to our present Invention we obviate these inconveniences by the use
of a rising and falling box The box is so mounted that its bottom can be raised
close up to the fire-bais or grid and remain there whilst the grid is smoothly and
quietly withdrawn by night and left handed screws or otherwise
The box can
then be lowered at any desired speed and the contents of the kiln will descend
uniformly with it When the box has descended to the extent required the grid is
replaced and the doors at the bottom of the box are opened to drop the material
which has been withdrawn from the kiln into a wagon The box can be raised and

page_text: lowered by chains, which also control the opening and closing of the doors To
effect this the ends of the lifting chains may be coupled by other short chains to
the two doors which form the bottom of the box When the chains are raised they
close the doors and then lift the box When the chains are lowered the box
descends until it is arrested by stops, any further lowering of the chains will then
allow the doors to open The position of the stops will govern the amount that is
withdrawn from the kiln at each withdrawal
In placo, also, of forming the hood of the kiln in two parts, which can be moved
away sidewise to allow of feeding in limestone or material, we make the hood in
one piece, which can be lifted up clear of the top of the kiln, and we form a
circular line of railway around the upper part of the kiin On this cucular railway
we place a trolly, on to which a truck canying the material to be fed into the
furnace can be run The trolly can then be moved round on the encular railway
to either side of the kiln to allow of the contents of the truck being discharged into
the kiln from any desued point By this means uniformity in the charging of the
kiln can readily be obtained
In the Drawings hereunto annexed we have shewn various views of a lime and
cement kiln constructed as above described.
Figure 1 is a front view and Figure 2 a vertical section of the kiln, Figure 3 18
a horizontal section shewing the moveable grids.
A, A, is the moving box, which can be raised so as to bring its bottom close up
to the grids B, B, C, C, are the doors forming the bottom of the box, they are
hinged to the plates A, and at thoir ends aro connected to chains D, by which they
can be opened and closed
The bars forming each of the guids are at their rear fixed to the frame of a small
truck E, which can be moved to and fro by screws F which extend from front to
back of the kiln, and have a right-handed thu cad cut at one end and a left-handed
thread on the opposite end, so that when the screws are turned the grids are moved
in opposite duections The screws work into nuts carried by the truck, and when
the guds are to be moved inwards or outwards they are revolved by turning the
crank handle G When the screws are to be thus turned the toothed wheel H on
the axis of the crank handle G is brought into gear with the wheel J on an axis K
On this axis are worms L which gear with worm wheels on the screws The
chains D by which the doors forming the bottom of the box A are opened and
closed are led over guide pullies M, and are attached to rollers N On the axis of
these rollers is another roller N₁ having a chain attached to it, which chain caries
a counterbalance P When the doors are to be opened or closed the axis of the
rollers N is turned by the crank handle G. To allow of this the axis of the crank
handle is slidden endwise to bring the small pinion Q on the axis of the mank
handle into gear with a toothed wheel R on an axis S, as shewn at Figure 1,
which axis by a pinion gives motion to a toothed wheel on the axis of the rollers N
T is a hinged catch, which is moved aside whenever the axis of the crank handle
1s to be slidden endwise, but which at other times forms an obstruction for a collar
on the axis to rest against, and so holds this axis in either of its positions, either
for moving the grids in or out, or for opening and closing the doors of the box A
The lower part of the kiln is composed of an iron casing U, as shewn, the lower
part of which serves as a guide for the rising and falling box A. When the
grids have been drawn back the box A is allowed to descend a distance from
the position shewn at Figure 2 The grids are then again moved forward and the
box is lowered further until the lower edge of the plates A come againt the stops V
The sides of the box being thus arrested the doors commence to open, and the lime
or cement resting upon them is discharged into the arch below The doors are
then again closed by winding up the chains D, and are in the same way lifted until
they come close up to the bottom of the grids
On the axis S is a brake wheel with a brake strap around it, which can be
tightened by a screw and hand wheel W. On this axis are also ratchet wheels

page_text: with teeth in opposite duections, and pawls engaging with these teeth, which lock
the axis whenever desired and keep the doors and box in any desired position.
Other auangements than those above described may be adopted for closing and
for raising and lowering the doors forming the bottom of the box A, and for
moving the grids in and out, but the arrangement shewn is well adapted for the
purpose
At Figures 4, 5, and 6 we have shewn on a smaller scale the way in which we
facilitate the feeding of materials into the top of the kiln X is the circular line
of railway around the top of the kiln, Y, a trolly running on same, on to which a
truck carrying the material to be fed into the furnace can be run, Z is the hood,
which can be lifted up clear of the top of the kiln and retained in any position by
counterbalance weights, as shewn
Having thus described the nature of our Invention and the manner of performing
the same, we would have it understood that we claim as our improvements in lime
and cement kilns,—
1st The combined anlangement, substantially as herein described, for with-
drawing from time to time measured quantities of line or cement from the bottom
of the kiln
2nd The combined arrangement of lifting hood and continuous tramway around
the top of a kiln, with truck running thereon for facilitating the uniform feeding of
material into the kiln, substantially as described
In witness whereof, I, the said James Hall, have hereunto set my hand and
seal, this Twenty-fifth day of July, in the year of our Loid One thousand
eight hundied and seventy-seven
'
JAMES HALL. (LS)
2