IMPROVEMENTS IN MILLS FOR GRINDING PAINTS OR OTHER SUBSTANCES
Year: 1877

page_text: LETTERS PATENT to Arthur John Berger, of Water Lane, Homerton, in the
County of Middlesex, a Partner in the Firm of "Lewis Berger & Sons," of
Homerton aforesaid, Paint, Color, &c., Manufacturers, for the Invention of
"IMPROVEMENTS IN MILLS FOR GRINDING PAINTS OR OTHER SUBSTANCES."
A communication from abroad by John W. Masury, of Brooklyn, in the County
of Kings, and State of New York.
Sealed the 10th May 1878, in pursuance of an Order of the Lord Chancellor, and
Sealed the 10th May 1878, in pursuance of an Order of the Lord Chancellor, and
dated the 18th October 1877.
PROVISIONAL SPECIFICATION left by the said Arthur John Berger at the
Office of the Commissioners of Patents on the 16th October 1877.
ARTHUR JOHN BERGER, of Water Lane, Homerton, in the County of Middlesex,
a Partner in the Firm of "Lewis Berger & Sons," of Homerton aforesaid, Paint,
Color, &c., Manufacturers. "IMPROVEMENTS IN MILLS FOR GRINDING PAINTS OR
OTHER SUBSTANCES." [A communication from abroad by John W. Masury, of
Brooklyn, in the County of Kings, and State of New York.]
The object and effect of such improvements, as herein-after set forth, is to over-
come a difficulty which has been considered insurmountable, that is to say, the re-
duction of hard pigments, wet with oil, to an impalpable fineness, because of the
great heat generated by the close contact of the grinding surfaces.
The following is a description of the construction of such improved mill-Upon
a cast-iron table are bolted three columns, which support the upper millstone bed.
Below is the lower millstone bed fastened to a hollow shaft. Both stone beds are
cast hollow. Upon these stonebeds rest thin annular millstones. The lower mill-
stone bed is rigidly fastened to a vertical hollow shaft, and receives its motion
through bevel gears from a horizontal shaft revolved by a pulley. This shaft is also
used to give motion to gear wheels, which revolve an arm in a cylindrical vessel
called a mixer, fixed upon and over the upper stone bed. The lower stone is raised

page_text: and brought in contact with the upper by means of a hollow screw step and wheel.
The upright driving shaft slides through the gear wheel in the same manner as the
vertical spindle of an upright drill.
The great object of the upper and lower millstone beds being cast hollow is in
order to circulate a constant stream of cold water through the chambers above and
below the stones.
The water which is used to cool the stones enters through a pipe in the upper
stone bed, circulates through the hollow space, and passes through a pipe into the
lower stone bed. After cooling the lower stone, the water passes through the
hollow shaft, to which is fastened the lower millstone bed, and is conveyed away by
suitable pipes.
The operation of the mill is as follows:-The material to be ground is put into
the mixer before mentioned, and gradually is fed into the mill by and through a
small valve. Here, after being thoroughly ground during its passage from the
centre to the circumference, it escapes at a discharge spout. The stones are pressed
into close contact by means of a screw wheel. The heat necessarily evolved by the
friction of surfaces in such perfect contact, instead of being imparted to the mixture,
is carried off by the constant stream of water running through the chambers above
and below the stones. The result is that paint comes from the mill with no
inaterial increase in temperature, being at the same time ground to a fineness never
before attained or deemed possible.
By a slight change in form, this mill is rendered available for grinding grain,
feed, and all kinds of dry materials. When so changed it is driven by a pulley on
the vertical shaft at a high rate of speed, and the material escapes at the circumfer-
ence in the same manner as from the ordinary millstone. In place of the standards
a circular cast-iron box with a spout is substituted. The only limit of the speed of
such a stone is the quantity of water that can be run through the mills; whereas in
all millstones heretofore constructed there has been a limit to such speed on account
of the heating of the substances.
As the temperature must necessarily be varied for different substances it is
proposed to do this by using either cold or hot water or steam, according to the
requirements of the substances under treatinent.
Having fully described such improvements, I claim as new, the hollow upper and
lower millstone beds, which said stone beds are cast hollow in order that a constant
stream of cold or hot water or steam may be circulated through the chambers
above and below the stones for the purpose of controlling the temperature of the
stones and the substance to be ground.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Arthur John Berger in the Great Seal Patent Office on the 10th May
1878.
ARTHUR JOHN BERGER, of Water Lane, Homerton, in the County of Middlesex, a
Partner in the Firm of "Lewis Berger & Sons," of Homerton aforesaid, Paint,
Color, &c., Manufacturers. "IMPROVEMENTS IN MILLS FOR GRINDING PAINTS OR
OTHER SUBSTANCES." [A communication from abroad by John W. Masury, of
Brooklyn, in the County of Kings, and State of New York.]
The object and effect of the improvements, herein-after set forth, is to overcome a
difficulty which has been considered insurmountable, that is to say, the reduction of
hard pigments, wet with oil, to an impalpable fineness, is a most difficult matter
because of the great heat generated by the close contact of the grinding stones,
which is in many cases injurious to both the stones and the paint, for which reason
it is highly necessary to control the temperature, which should be varied for
different substances, which can be effected by the said improvements by using hot
or cold water or steam, according to the requirements of the substances under treat-
ment.
The Drawing accompanying this Specification is a sectional elevation of a paint
mill constructed according to the said improvements. A reference thereto and to
the following description particularly describes and ascertains the nature of the
said improvements, and the manner in which the same are to be performed.
The alphabetical letters of reference used hereafter in this Specification, and upon
the sectional elevation Drawing, indicate corresponding parts.
Upon "A," "A," a cast-iron table are bolted three columns "B," "B," which
support the upper millstone bed. Both stone beds are cast hollow, the spaces being
represented by "G," "G," "G," "G." Upon these stone beds rest the thin annular
millstones, which are shewn in " 'F," F." The lower millstone bed is rigidly
fastened to the hollow shaft "J," and receive its motion through the bevel gears
"K," "K," from the horizontal shaft, which is revolved by the pulley G. This shaft
is also used to give motion to the gear wheels “E,” “E," which revolve an arm in
the mixer "M." The lower stone is raised and brought into contact with the upper
by means of the hollow screw step "S" and the wheel "W." The upright driving
shaft slides through the gear wheel in the same manner as the vertical spindle of an
upright drill.
The water which is used to cool the stones enters through a pipe in the upper
stone bed, circulates through the hollow space "G," "G," "G" "G," and passes
through the pipe "I" in the direction of the arrows into the lower stone bed. After
cooling the lower stone, the water passes through the hollow shaft "J," and is con-
veyed away by suitable pipes through the outlet "O."
The operation of the mill is as follows:-The material to be ground is put into
the mixer "M," and gradually is fed into the mill through the small valve re-
presented in the Drawing. Here, after being thoroughly ground during its passage
from the centre to the circumference, it escapes at a scraper, such as is ordinarily
used for delivering the ground paint. The millstones are pressed into close contact
by means of the screw wheel "W." The heat necessarily evolved by the friction of
surfaces in such perfect contact, instead of being imparted to the paint or mixture,
is carried off by the constant stream of water running through the spaces or
chambers "G," "G," "G," "G," above and below the stones. The result is that the
paint comes from the mill with no material increase in temperature, being at the
same time ground to a fineness never before attained or deemed possible.
By a slight change in form, this mill is rendered available for grinding grain,
feed, and all kinds of dry materials, and by any suitable pipe connections, a circula-
tion of cold or hot water or steam can be maintained for controlling the tem-

page_text: perature of the stones, and the substance being ground, according to the nature and
requirements of the substances under treatment.
I do not therefore limit myself to the employment or application of my improve-
ments specifically for paint mills, but claim protection for their adaptation or
application to mills for grinding all kinds of wet and dry substances.
When the mill is changed in form to render it available for grinding grain, feed,
or other kinds of dry materials, it can be driven by a pulley on the vertical shaft at
a high rate of speed, and the material escapes at the circumference in the same
manner as from the ordinary millstone. In place of the standards a circular cast-
iron box with a spout is substituted.
37 24
Having thus described my Invention, I claim as new, and desire to secure by
Letters Patent, the combination with the hollow shaft "J" to which the lower
millstone bed is rigidly fastened, of the hollow upper and lower millstone beds,
forming the spaces "G," G," "G," "G," to allow of a stream of water entering
through a pipe in the upper stone bed, circulating through the hollow spaces "G,"
"G," "G," "G," through the pipe "I" into the lower stone bed, thence through
the hollow shaft "J," substantially as set forth.
In witness whereof, I, the said Arthur John Berger, have hereunto set my
hand and seal, this Tenth day of May, in the year of our Lord One thousand
eight hundred and seventy-eight,
ARTHUR JOHN BERGER. (L.S.)