IMPROVEMENTS IN MACHINES FOR SIFTING OR STRAINING PAINTS OR COLORS
Year: 1883

page_text: LETTERS PATENT to John Clayton Mewburn of 169 Fleet Street in the City
•
of London, Patent Agent and Consulting Engineer for an Invention of
"IMPROVEMENTS IN MACHINES FOR SIFTING OR STRAINING PAINTS OR
COLORS" communicated to him from abroad by Jean Charles Matter of
1 Boulevard St Denis Paris France
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn
at the Office of the Commissioners of Patents on the 25th September 1883.
JOHN CLAYTON MEWBURN of 169 Fleet Street in the City of London Patent
Agent and Consulting Engineer "IMPROVEMENTS IN MACHINES FOR SIFTING OR
STRAINING PAINTS OR COLORS" [communicated to him from abroad by Jean
Charles Matter of 1 Boulevard St Denis Paris France]
The main object of this invention is to construct a machine for effecting the
sifting or straining of paints or colors such as now done by hand labor.
The process of sifting as effected by hand labor being long and expensive and
injurious to the workmen, various attempts have been made to invent a suitable
machine for the purpose, but those hitherto employed such as apparatus for sifting
by means of vacuum and by means of a piston have not been successful so far as
the product obtained is concerned. The colors or paints sifted thereby have been
found in much the same state as before the sifting, the grains or lumps not being
broken as they are by the action of the brush worked by hand. The operation
when performed by hand however necessitates frequent renewal of the sieves which
soon get worn owing to the blows of the brushes operated by the workman.
The machine which forms the subject of the present invention combines the
economical advantages of mechanical work with those of manual labor.
The invention is chiefly characterized by the movement of the brush in the
reverse direction to that of the sieve and with an amplitude such that every point
of the sieve comes successively in contact with the brush; by the elasticity of the
pressure of the brush upon the sieve; and by an arrangement forming an integral
part of the machine whereby the sieve bottoms can be readily removed and
replaced.

page_text: The machine is generally constructed double, that is to say, with one driving
shaft to two sieves, but it can be made with a single sieve or with more than two
sieves. The shaft has a fast and loose pulley and by bevel gearing drives a vertical
shaft for each sieve. To one end of this shaft is keyed a crank the pin of which
engages a lever for communicating a circular motion to the brush. The brush is
jointed to the end of a red movable around a given point and passing through a
ring at the end of the lever; the brush thus participates in the movement of the
lever and the articulated mounting allows it to move in all directions and to be in
a manner flexible and elastic. A counterweight regulates the pressure of the brush
on the bottom of the sieve. The sieve rests on a toothed base which is driven by
a pinion in a reverse direction to the brush. The machine thus realizes the
advantages due to manual sifting viz :-continuity and regularity of work and
equality of pressure.
The bottom of the sieve which is formed of wire gauze or metallic cloth is fitted
between two rings at the base of the trough; one of the rings is placed within a
frame supported by uprights and the other ring is placed on another. frame which
can be moved vertically by means of a screw and hand wheel. The gauze or cloth
is placed between the two rings while the under one with its frame is lowered and
the under ring is then raised by means of the screw until the edge of the gauze is
held firmly between the two rings.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed,
by the said John Clayton Mewburn in the Patent Office on the 20th March
.
1884.
JOHN CLAYTON MEWBURN of 169 Fleet Street in the City of London Patent
Agent and Consulting Engineer 'IMPROVEMENTS IN MACHINES FOR SIFTING OR
STRAINING PAINTS OR COLORS" (A communication to me from abroad by Jean
Charles Matter of 1 Boulevard St Denis, Paris, France)
The main object of this invention is to construct a machine for effecting the
sifting or straining of paints or colors such as is now done by hand labor.
The process of sifting as effected by hand labor being long and expensive and
injurious to the workmen, various attempts have been made to invent a suitable
machine for the purpose, but those hitherto employed such as apparatus for sifting
by means of vacuum and by means of a piston have not been successful so far as
the product obtained is concerned.
The colors or paints sifted thereby have been found in much the same state as
before the sifting, the grains or lumps not being broken as they are by the action
of the brush worked by hand-The operation when performed by hand however
necessitates frequent renewal of the sieves which soon get worn owing to the blows
of the brushes operated by the workmen.
The machine which forms the subject of the present invention combines the
economical advantages of mechanical work with those of manual labor.
The invention is chiefly characterized by the movement of the brush in the
reverse direction to that of the sieve and with an amplitude such that every point
of the sieve comes successively in contact with the brush; by the elasticity of the
pressure of the brush upon the sieve; and by an arrangement forming an integral
part of the machine whereby the sieve bottoms can be readily removed and
replaced.
Figure 1 of the annexed drawings is an elevation and Figure 2 a plan of a
machine constructed according to this invention.
The machine is generally constructed double that is to say with one driving shaft
to two sieves but it can be made with a single sieve or with more than two sieves.
A A¹ is the driving shaft; it has a fast and loose pulley P P¹ and by bevel
gearing a a¹ drives a vertical shaft B and B¹ one for each sieve. To one end of this
shaft B or B¹ is keyed a crank C or C₁ the pin of which engages a lever D for
communicating a circular motion to the brush. The brush E or E¹ is jointed to the
end of a rod Ğ or G' movable around a point b and passes through a ring c or c² at
the end of the lever D; the brush thus participates in the movement of the lever
and the articulated mounting allows it to move in all directions and to be in a
manner flexible and elastic.
A weight H or H' regulates the pressure of the brush on the bottom of the
sieve. The sieve rests on a toothed base I or I¹ which is driven by a pinion d in a
reverse direction to the brush. The machine thus realizes the advantages due to
manual sifting viz:-continuity and regularity of work and equality of pressure.
The bottom of the sieve which is formed of wire gauze or metallic cloth is fitted
between two rings at the base of the trough; one of the rings is placed within a
frame K supported by uprights L L and the other ring is placed on another
frame M which can be moved vertically by means of a screw N and hand wheel O.
The gauze or cloth is placed between the 2 rings (while the under one with its
frame is lowered) and the under ring is then raised by means of the screw until
the edge of the gauze is held firmly between the two rings

page_text: Having now described the nature of the said invention as communicated to me
and in what manner the same is to be performed I declare that I claim :-
Constructing machines for sifting or straining paints or colors substantially as
herein before described and represented in the accompanying drawings.
In witness whereof I the said John Clayton Mewburn have hereunto set my
hand and seal this nineteenth day of March One thousand eight hundred and
eighty four.