IMPROVEMENTS IN PULVERIZING MACHINES BAD CENT MINERALS AND OTHED SUBSTANONG ANT IN DIST COLLECTING PROVISIONAL SPECIFICATION
Year: 1880

page_text: LETTERS PATENT to Wilhelm Michaëlis, of 15, Friedenstrasse, Berlin, in the
Kingdom of Prussia, at present of Royal Hotel, Blackfriars, in the City of
London, for an Invention of "IMPROVEMENTS IN PULVERIZING MACHINES
BAD CENT MINERALS AND OTHED
SUBSTANONG ANT
IN DIST COLLECTING
PROVISIONAL SPECIFICATION left by the said Wilhelm Michaëlis at the
Office of the Commissioners of Patents on the 11th October 1880.
WILHELM MICHAËLIS, of 15, Friedenstrasse, Berlin, in the Kingdom of Prussia,
at present of Royal Hotel, Blackfriars, in the City of London. IMPROVEMENTS
IN PULVERIZING MACHINES FOR CEMENT, MINERALS, AND OTHER SUBSTANCES,
AND IN DUST COLLECTING CHAMBERS FOR THE SAME’
"
My improved pulverizing machine consists of an iron circular box, in which a
steel disc provided with beaters and fanblades rotates with great velocity. The
material which is to be pulverized is introduced by means of a hopper and an
archimedian screw through near the centre of one side of the box. The feed is
regulated from the shafting of the apparatus. The material is thrown against the
periphery of the box, which periphery is lined with hardened iron or steel plates,
where the material is kept by the motion of the disc till it is pulverized.
The fine dust is carried away by means of the current generated by the disc, or
by a separate blowing apparatus from the pulverizer into a dust, chamber. The
dust chamber is a spacious structure, inside of which in the upper part there is
another chamber covered with cloth. This cloth allows the air to pass, but not the
dust, and is shaken by mechanical means to prevent its being clogged by the dust.
In order to reduce the pressure of the air in the dust chamber, a part of the air is
carried back through a tube into the pulverizing apparatus. This return is
regulated by means of a valve. The pulverized material, which is collected at the
bottom of the dust chamber is carried away by means of an archimedian screw or
by other means.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Wilhelm Michaëlis in the Great Seal Patent Office on the 11th April
1881.
WILHELM MICHAELIS, of 15, Friedenstrasse, Berlin, in the Kingdom of Prussia,
and late of Royal Hotel, Blackfriars, in the City of London. "IMPROVEMENTS IN
PULVERIZING MACHINES FOR CEMENT, MINERALS, AND OTHER SUBSTANCES, AND
IN DUST COLLECTING CHAMBERS FOR THE SAME."
My improved pulverizing machine consists of an iron circular box, in which a
steel disc provided with beaters and fanblades rotates with great velocity. The
material which is to be pulverized is introduced by means of a hopper, and an
archimedian screw through an opening near the centre of one side of the box. The
feed is regulated from the shafting of the apparatus. By the motion of the disc
the material is thrown, against the periphery of the box, and kept there till it is
pulverized, the periphery being lined with hardened iron or steel plates. The fine
dust is carried away from the pulverizer into a dust chamber by means of the
current generated by the disc, or à separate blowing apparatus. The dust chamber
is a spacious structure, inside of which in the upper part there is another chamber,
a framework covered with cloth. This cloth allows the air to pass, but not the
dust, and is shaken by mechanical means to prevent its being clogged by the dust.
In order to reduce the pressure of the air in the dust chamber, a part of it is carried
back through a tube into the pulverizing apparais This return is regulated by
means of a valve. The pulverized material, which is collected at the bottom of the
dust-chamber is carried away by means of an archimedian screw or by other
means.
Having set forth the nature of this Invention, I will now further explain the
same by means of the accompanying Drawing, in which like letters designate
like parts.
Fig. 1 in the Drawing is a vertical section through the pulverizer.
Fig. 2 is an elevation of the same.
Fig. 3 is a plan of the same.
Fig. 4 is an elevation of the pulverizing chamber with the upper half removed
to show the inside arrangement.
Fig. 5 is a vertical section through the dust chamber showing the whole
arrangement.
Fig. 6 is a plan of the same.
The
The pulverizing apparatus consists of a cast iron circular box O, in which a steel
dise R provided with a number of beaters P and fan blades Q, say, eight of each,
rotates with great velocity, say, 1000 or 1050 revolutions per minute.
material which is to be pulverized is put into the hopper S and pushed on by
the archimedian screw T into the pulverizing chamber. It passes the beating
bars U made of steel, which crush such pieces as are too thick. The material is
then struck by the beaters P, and by them thrown against the periphery of the
circular box, which periphery is lined with smooth or grooved plates of steel or
chilled cast iron. Here it is worked upon between the dise and these hard surfaces
till it becomes dust, and is carried away by the air current created by the fan-
blades Q through the further centre of the pulverizing chamber, and through the
tube X into the dust collecting chamber. The tube X may be rising, horizontal,
or falling.
The dust, collecting chamber is a structure A made, say, of wood or brickwork,
d has in its upper part a chamber B, which can be mechanically shaken to
pret the cloth of which the sides are formed from being clogged by the dust.
The chher B is shown as a suspended chamber in Fig. 5. The cloth-sides are of

page_text: a suitable texture to let the air pass through, but little or no dust. Such dust or
powder which is too coarse is caught by the inclined plane C, the incline of which
may be regulated, and is carried away by the archimedian screw D, and may then
be put again into the pulverizer. The air in the upper dust-chamber is partly
carried back to the pulverizer through the tube Y, thus the pressure in the dust
chamber may be reduced to a minimum; a valve regulates this return. The fine
dust in this returning air is prevented from falling amongst the coarser particles in
the trough C by the superposed trough g. The screw F clears the trough g through
the tube H.
Sometimes a separate blowing apparatus may be added, the dimensions of which
are regulated by the desired fineness of the dust.
Having now described the nature of the Invention, and in what manner the
same is to be performed, I claim,―
First. The pulverizing apparatus with the continuous feeding arrangement,
substantially as above described.
Second. The arrangement of the circulation of the air from the dust chamber to
the pulverizing chamber, substantially as above described.
Third. The arrangement of the dust collecting chamber, substantially as above
described.
In witness whereof, I, the said Wilhelm Michaëlis, have hereunto set my hand
and seal, this Sixth day of April, in the year of our Lord One thousand
eight hundred and eighty one.