Improvements in Apparatus for Purifying and Grinding the Residue of Portland Cement.
Year: 1892

page_text: Date of Application, 26th May, 1892
Complete Specification Left, 22nd Mar., 1893-Accepted, 26th July, 1893
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Purifying and Grinding the Residue
of Portland Cement.
I, JOHN HOYLE, of Cliff House, Swanscombe, Kent, Assistant Manager of
Cement Works, do hereby declare the nature of this invention to be as follows:-
In the grinding of Portland cement much of the hardest and best material fails
to be reduced during the first passage through the mill to the fineness necessary to
enable it to pass through the prescribed sieve. It is now usual to pass this residue
back to the mill from which it came and there to grind it again together with
fresh clinker.
Now I have found that the residue can be much more advantageously dealt with
separately by regrinding it without admixture with new material and in an apparatus
specially designed for this purpose.
A leading feature in the apparatus which I employ is that the grinding is
effected between conical surfaces made of a stone like composition containing a
large proportion of emery nevertheless grinding surfaces of other stone may be
employed.
be
The apparatus consists of coned rings mounted upon a vertical axis and revolving
within other stationary cone rings so that the surfaces are in close proximity. The
cement residue is caused to pass between the grinding surfaces but before doing so
it is made to pass over magnet poles arranged so that any particles of iron may
retained whilst the rest of the material is delivered to the uppermost pair of
grinding rings by which it is to some extent reduced. The residue descends from
the first pair of rings to another pair immediately below and is further reduced and
I may use as many pairs of emery rings as may be necessary in each case
to effect the object. The several pairs of rings may be on the same axis or upon
separate axes as may be preferred.
so on.
Dated thin 26th day of Mor 1002
CARPMAEL & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Purifying and Grinding the Residue
of Portland Cement.
I, JOHN HOYLE, of Cliff House, Swanscombe, Kent, Assistant Manager of
Cement Works, 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 :-
In the grinding of Portland cement much of the hardest and best material fails to
be reduced during the first passage through the mill to the fineness necessary to
enable it to pass through the prescribed sieve. It is now usual to pass this residue
back to the mill from which it came and there to grind it again together with
fresh clinker.
Now I have found that the residue can be much more advantageously dealt with
separately by regrinding it without admixture with new material and in an apparatus
specially designed for this purpose.
A leading feature in the apparatus which I prefer to employ is that the grinding
is effected between conical surfaces made of a stone like composition containing a
large proportion of emery nevertheless grinding surfaces of other stone or of iron
or steel may be employed.

page_text: The apparatus consists of coned rings mounted upon a vertical axis and revolving
within other stationary cone rings so that the surfaces are in close proximity. The
cement residue is caused to pass between the grinding surfaces but before doing so
it is made to pass over magnet poles arranged so that any particles of iron may be
retained whilst the rest of the material is delivered to the uppermost pair of
grinding rings by which it is to some extent reduced. The residue descends from
the first pair of rings to another pair immediately below and is further reduced and
80 on. I may use as many pairs of emery rings as may be necessary in each case
to effect the object. The several pairs of rings may be on the same axis or upon
separate axes as may be preferred.
DESCRIPTION OF THE DRAWINGS.
It is
Figure 1 is a front elevation (partly in section) of the machine for removing
particles of iron and Figure 2 is a vertical section of the same on line x x Figure 1.
a is a hopper for supplying the partly ground cement to the sieve b of ordinary
construction supported by the springs and shaken by the rod b². This sieve has
a tray of perforated steel or zinc through which the residue is able to pass.
merely a grating to intercept any large foreign substances that might accidentally
drop into the residue. c is a hopper which receives the sifted material and delivers
it by the two doors or openings c¹ on to the incline c² and magnets d. The latter
are ordinary permanent horse shoe magnets screwed to a wooden roller and the
interstices filled with Keen's cement. Their inoperative parts that is to say their
bends are covered by the wood lagging d¹ (Figure 1). The roller is mounted on
the axis d and rotated by the pulley d³. e is a cylindrical brush driven in the
opposite direction to the magnets by the pulley el on its axis. This brush sweeps
off any particles of iron arrested by the magnets into the shoot whilst the cement
falls into the shoot g and is delivered by the elevator g' and shoot g² into the
hopper of the grinding mechanism which is shown at Figures 3, 4 and 5 ;
Figure 3 being an end elevation, Figure 4 a side elevation and Figure 5 a section
of one pair of cone rings to a larger scale.
The material passes from the hopper / to the hopper ' through the first pair ; of
cone rings and by the shoot j' to the second pair k and from thence by the shoot k
to the third pair l. In some cases sieves or separators are placed between the
successive pairs to remove the dust or fine cement and so increase the output of the
machine.
In Figure 5 m is the upper cone ring which is fixed, its height being adjusted by
the packing rings m³. is the lower cone ring connected by the plates n' to the
axis 2 to whose lower end is fixed the bevel pinion n³ (Figures 3 and 4) gearing
with the bevel pinion o' on the shaft O.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In apparatus for grinding the residue of Portland cement the combination of
two or more pairs of conical grinding surfaces operating in succession substantially
as described.
2. The combination with apparatus such as is referred to in Claim 1 of the
magnetic separator substantially as described.
3. Apparatus for purifying and grinding the residue of Portland cement
substantially as described and shown in the drawings.
Dated this 15th day of March 1893.
J. HOYLE.

page_text: Date of Application, 26th May, 1892
Complete Specification Left, 24th Feb., 1893-Accepted, 26th July, 1893
PROVISIONAL SPECIFICATION.
Improvements in Purifying and Grinding the Residue of
Portland Cement.
JOHN HOYLE Cliff House Swanscombe Kent Assistant Manager of Cement
Works, do hereby declare the nature of this invention to be as follows:-
In the grinding of Portland cement much of the hardest and best material fails
to be reduced during the first passage through the mill to the fineness necessary to
enable it to pass through the prescribed sieve. It is now usual to pass this residue
back to the mill from which it came and there to grind it again together with fresh
clinker.
Now I have found that the residue can be much more advantageously dealt with
separately by regrinding it without admixture with new material and in an
apparatus specially designed for this purpose.
A leading feature in the apparatus which I employ is that the grinding is
effected between conical surfaces made of a stone like composition containing a
large proportion of emery, nevertheless grinding surfaces of other stone may be
employed.
The apparatus consists of coned rings mounted upon a vertical axis and
revolving within other stationary cone rings so that the surfaces are in close
proximity. The cement residue is caused. to pass between these grinding surfaces
but before doing so it is made to pass over magnet poles arranged so that any
particles of iron may be retained whilst the rest of the material is delivered to the..
uppermost pair of grinding rings by which it is to some extent reduced. The
residue descends from the first pair of rings to another pair immediately below and
is further reduced and so on. may use as many pairs of emery rings as may be
necessary in each case to effect the object. The several pairs of rings may be on
the same axis or upon. separate axes as may be preferred.
Dated this 26th day of May 1892..
CARPMAEL & Co.,
Agents.
COMPLETE SPECIFICATION..
Improvements in Purifying and Grinding the Residue of
Portland Cement.
I, JOHN HOYLE, Cliff House, Swanscombe, Kent, Assistant. Manager of Cement
Works, 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 :-
In the grinding of Portland cement much of the hardest and best material fails
to be reduced during the first passage through the mill to the fineness necessary to
enable it to pass through the prescribed sieve. It is now usual to pass this residue
back to the mill from which it came and there to grind it again together with fresh
clinker.
Now I have found that the residue can be much more advantageously dealt with
separately by regrinding it without admixture with new material and in an
apparatus specially designed for this purpose.
A leading feature in the apparatus which I prefer to employ is that the grinding
is effected between conical surfaces made of a stone like composition containing
a large proportion of emery nevertheless grinding surfaces of other stone or of iron
or steel may be employed.

page_text: The apparatus consists of coned rings mounted upon a vertical axis and revolving
within other stationary cone rings so that the surfaces are in close proximity. The
cement residue is caused to pass between the grinding surfaces but before doing so
it is made to pass over magnet poles arranged so that any particles of iron may be
retained whilst the rest of the material is delivered to the uppermost pair of
grinding rings by which it is to some extent reduced. The residue descends from
the first pair of rings to another pair immediately below and is further reduced and
So on. I may use as many pairs of emery rings as may be necessary in each case
to effect the object. The several pairs of rings may be on the same axis or upon
separate axes as may be preferred.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a front elevation (partly in section) of the machine for removing
particles of iron and Figure 2 is a vertical section of the same on line x x
Figure 1.
a is a hopper for supplying the partly ground cement. to the sieve 6 of ordinary
construction supported by the springs and shaken by the rod b². This sieve has
a tray of perforated steel or zinc through which the residue is able to pass. It is
merely a grating to intercept any large foreign substances that might accidentally
drop into the residue. c is a hopper which receives the sifted material and delivers
it by the two doors or openings c¹ on to the incline e² and magnets d. The latter are
ordinary permanent horse shoe magnets screwed to a wooden roller and the
interstices filled with Keen's cement. Their inoperative parts that is to say their
bends are covered by the wood lagging d¹ (Figure 1). The roller is mounted on the
axis d² and rotated by the pulley de is a cylindrical brush driven in the opposite
direction to the magnets by the pulley e¹ on its axis. This brush sweeps off any
particles of iron arrested by the magnets into the shoot whilst the cement falls into
the shoot g and is delivered by the elevator g' and shoot g² into the hopper of
the grinding mechanism which is shewn at Figures 3, 4 and 5; Figure 3 being an
end elevation, Figure 4 a side elevation and Figure 5 a section of one pair of cone
rings to a larger scale.
The material passes from the hopper / to the hopper through the first pair ; of
cone rings and by the shoot j' to the second pair k and from thence by the shoot k¹
to the third pair 1. In some cases sieves or separators are placed between the
successive pairs to remove the dust or fine cement and so increase the output of the
machine.
In Figure 5 m is the upper cone ring which is fixed, its height being adjusted by
the packing rings m¹. n is the lower cone ring connected by the plates n' to the
axis n² to whose lower end is fixed the bevel pinion n³ (Figures 3 and 4) gearing
with the bevel pinion o¹ on the shaft O.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
In the manufacture of cement the combined process of first grinding and sifting
the clinker then passing the residue over magnets and again grinding it substantially
as described.
Dated this 22nd day of 1002
JOHN HOYLE.