A Stirring Device to Overcome the Formation of Skins or Films in the Storing or Keeping of Lacquers, Varnishes, Oil Colours, and other Substances Liable to Form a Skin or Film on the Top.
Year: 1899

page_text: Date of Application, 2nd Aug., 1899-Accepted, 2nd Sept., 1899
COMPLETE SPECIFICATION.
A Stirring Device to Overcome the Formation of Skins or Films in
the Storing or Keeping of Lacquers, Varnishes, Oil Colours, and
other Substances Liable to Form a Skin or Film on the Top.
I, HEINRICH WILHELM NICOLAUS AHRENS, of 4, Hafenstrasse, Elmshorn, Ger-
many, Merchant, 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:.
-
It is very objectionable that lacquers, varnishes, oils colours and other sub-
stances form a film or skin on top when stored or kept in vessels, which film
becomes thicker and thicker with time. This formation of the skin or film is
based upon a continuous oxidising process, which causes the lacquers, varnishes,
&c., to become thick and resinous, and cannot be avoided by the exclusion of
air, because materials rich of oxygen, contained in the varnishes, lacquers, oil
colours, etc., such as oxide of lead, oxide of manganese, etc., easily yield their
oxygen and thus cause continuous slow oxidation. When such lacquers, varnishes,
or oil colours, are used for painting, the firm skin like particles render the painted
surfaces uneven, and the removal of all such skin like particles, occupies too much
time. Further there is a considerable loss of material caused by the removal of
the thick or skin like particles, particularly when the paints &c. are kept for some
time.
This invention relates to apparatus which is designed to obviate these disad-
vantages and thus to render the painting and similar work better and to effect a
saving of material. This is effected by mixing the thick particles with the other
material, so as to render their removal unnecessary and to avoid their waste,
the quality of the material remaining unimpaired.
The apparatus consists essentially of a frame fixed to a rotary vertical axle in
the vessel containing the oil point or similar material. The frame has vertical
ribs of a triangular cross section arranged at both sides of the axle, so that the
least possible resistance is offered to the passage of such ribs through the material.
The ribs near to the sides of the vessel are arranged so that very little free space
is left between the wall of the vessel and the side of the rib turned towards it
The lower end of the ribs are provided with plough like continuations. When
the device is rotated, the skin or film is disintegrated into very minute particles
and mixed intimately with the rest of the material by the peculiar arrangement
of the ribs.
The accompanying drawings illustrate how this invention may be carried into
effect.
Figure 1 is a vessel with the mixing device arranged therein.
Figure 2 shows a transverse section through the mixing frame and vertical ribs.
Figure 3 is a view of one of these ribs with the plough like continuation.
A vessel a contains an axle b resting in suitable bearings and carrying a frame c
with vertical connecting ribs d, which are in the form of triangular prisms and
arranged at both sides of the axle in such a manner that the edges cutting through
the material rotate in the same direction and receive very little resistance. The

page_text: ribs d may be provided in any suitable number according to the shape and size of
the vessel. These ribs which are not close to the side of the vessel have con-
veniently isosceles or equilateral triangular cross section. The ribs close to the
side of the vessel are formed so that the space between the side turned to the
vessel and the latter is as small as possible, and they are so close to the side of
the vessel as to rub the small pieces of film or skin into the same consistency
as the paint etc. The lower ends of the ribs have plough like projections to stir
the material at the bottom and to assist in the rubbing of the film or skin.
The effect of the use of the apparatus is as follows:.
The vessel a is closed as tightly as possible, whereby the formation of film or
skin is counteracted to a great extent. Before withdrawal of any of the contents
of the vessel through the orifice f, a crank is attached to the square g of the
axle and the latter is rotated, the contents of the vessel being thoroughly worked
up and the film ground up and mixed intimately with the material by the ribs
and plough like projections. If the contents are only seldom used, it is preferable
to stir them up occasionally and thus to rub up the film and mix it to prevent the
film becoming too thick.
To allow of the removal of the rotary device from the vessel for repairing or
cleaning the vessel, the latter is preferably cylindrical and has a tight fitting
cover. If the vessel has a conical top, the latter should be connected with the
cylindrical part so that the conical top can be removed or attached with ease.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim is:-
A mixing device for preventing the formation of films or skins in keeping
lacquers, varnishes, oil paints, and similar substances, consisting of a vessel a,
having a pivotted axle b, carrying a frame c, provided with a suitable number of
triangular prismatic ribs, having plough like projections, and arranged in rows
at two sides of the axle; so that when the axle is rotated, the ribs are rotated all
in one direction, and that the ribs close to the side leave little space between
themselves and the side of the vessel, substantially as described.
Dated this 2nd day of August 1899.
FELL & JAMES,
Agents for the Applicant.