IMPROVEMENTS IN AND RELATING TO DUST-COLLECTORS FOR MILLS, WAREHOUSES, AND INDUSTRIAL WORKS
Year: 1882

page_text: LETTERS PATENT to Pieter Van Gelder of Sowerby Bridge in the County
of York Milling Engineer for an Invention of "IMPROVEMENTS IN AND
RELATING TO DUST-COLLECTORS FOR MILLS, WAREHOUSES, AND INDUSTRIAL
WORKS"
PROVISIONAL SPECIFICATION left by the said Pieter Van Gelder at the
Office of the Commissioners of Patents on the 6th February 1882.
PIETER VAN GELDER of Sowerby Bridge in the County of York Milling
Engineer "IMPROVEMENTS IN AND RELATING TO DUST-COLLECTORS FOR MILLS
WAREHOUSES AND INDUSTRIAL WORKS"
The dust which collects in mills and other places is not merely a serious nuisanco
but is sometimes a danger as it is apt to forin an explosive mixture with the air.
Even in coal inines it is found that air laden with dust will explode with a much
Emaller percentage of gas than air-not dust-laden.
In flour mills it is customary to bring the exhaust air from purifiers and other
machines to a special stive room.
Now my Invention is designed to supersede that stive room. It consists in an
air filtering apparatus so arranged that the currents of air shall bend sharply round
allowing the larger particles to separate by their impetus at this point also causing
the dusty air to pass through corrugated air filters of any ordinary or desired con-
struction armed with shaking or knocking mechanism. Through these filters the
air passes in an upward direction. Several (an indefinite number) of these filters
are superimposed and preferably connected to the same entrance and exit passages.
The machinery or train of gearing that actuates the knocking or shaking mechanisin
of all the filters also shuts off (and afterwards turns on) in succession and at stated
intervals both the entrance and exit of each of these filters. The same valves that
turn off the entrance and exit also at the same instant open and afterwards close
two air passages which supply a current of clean air traversing down through the
filter and in the contrary direction to that taken by air to be filtered. This air
current aided by the shaking or knocking cleans the insterstices of the filtering
surface.

page_text: Below the filtering surface is a revolving curved scraper or its equivalent which
travelling round on the floor under the filter pushes the dust out through a side
hole. In order to make the pressure of air uniform, the exit exhaust fan and the
fans causing the air to enter the apparatus are so regulated that there shall be
almost exactly the same barometric pressure on both sides of the filter notwith-
standing the friction of the pipes and filter. This is done by making the exhaust
fan a little the more powerful also the dusty air brought from the various machines
descends through a vertical sleeve to near the bottom of a box with gauze sides
and out through an orifice at the top to the filters. The coarsest and heaviest
particles are left in the bottom of the box while the air entering through the gauze
or escaping out through the same causes a constantly uniform pressure to be
maintained in the entrance to the filtering chamber. The stive is removed by an
Archimedean screw and is pressed by it through a horizontal passage sufficiently
long to form an air lock

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Pieter Van Gelder in the Great Seal Patent Office on the
5th August 1882.
PIETER VAN GELDER of Sowerby Bridge in the County of York, Milling
Engineer. "IMPROVEMENTS IN AND RELATING TO DUST COLLECTORS FOR MILLS,
WAREHOUSES, AND INDUSTRIAL WORKS"
The dust which arises in mills and other places, such as warehouses and industrial
works, is not merely a serious nuisance but is somtimes a danger as it is apt to
form an explosive mixture with the air.
In coal mines it is found that air laden with dust will explode with a much
smaller percentage of gas than air not dust-laden.
In flour mills it is customary to bring the exhaust air, from purifiers and other
machines to a special stive room.
Now my Invention while particularly designed to supersede that stive room, will
also be found of great value in warehouses and industrial works where dust laden
air is required to be purified.
The Invention will be best understood by reference to the accompanying Sheets
of Drawings which illustrate the improvements as applied to a flour mill in placo
of the above mentioned stive room.
Fig: 1 is an elevation, partly in section, of the apparatus. Fig: 2 plan of
same.
Fig: 3 is an enlarged elevation partly in section of mechanism for actuating
filters and valves hereafter described. Fig: plan of same. Figs: 5 and 6
diagrams of valves.
The Invention consists in an air filtering apparatus so arranged that the currents
of air to be purified shall bend sharply round allowing the larger particles to
separate, by their impetus, at this point; also in causing the dusty air to pass
through corrugated or other air filters A, of any ordinary or desired construction,
armed with shaking or knocking mechanism, the Drawings show a shaking
mechanism.
Through these filters A the air passes in an upward direction. Several (an
indefinite number) of these filters are superimposed, as shown, and preferably
connected to the same entrance and exit passages C and D, as shown.
The machinery or train of gearing that actuates the knocking or shaking
mechanism of all the filters, shown in Figs: 3 and 4 and hereafter described, also
shuts off (and afterwards turns on) in succession and at stated intervals both the
entrances E and exits F simultaneously to each of these filters.
The same exit valves, shown in Figs: 5 and 6 and hereafter described, that turn
off the entrance and exit, also at the same instant open, and afterwards close the
air-passages which supply a current of clean air, (preferably heated to prevent con-
densation) traversing down through the filter and in the contrary direction to that
taken by air to be filtered. This air current aided by the shaking or knocking,
cleans the interstices of the filtering surface.
Below the filtering surface is a revolving curved scraper G, or its equivalent,
which travelling round on the floor, under the filter pushes the dust out through a
side hole H; by a narrow opening fitted with a self closing valve.
In order to make the pressure of air uniform the exhaust fan I and the fans J
causing the air to enter the apparatus are so regulated that there shall be almost
exactly the same barometric pressure on both sides of the filter A notwithstanding
the friction of the dust laden air against the pipes or passages and the filter.

page_text: This is done by making the exhaust fan a little the more powerful whether the
entrance fans be special or simply forming parts of the machines producing the
dust.
The dusty air brought from the various machines is preferably made first to
descend through a vertical sleeve K to near the bottom of a box B with gauze sides,
and out through an orifice L at the top to the filters. The coarsest, and heaviest
particles are left in the bottom of the box while the air entering through the gauze,
or escaping out through the same causes a constantly uniform pressure to be
maintained in the entrance to the filtering chamber.
The mode of action is as follows. The dusty air coming from one or more
machines, one is shown in the Drawings, passes through passages M and descends
through the vertical sleeve K to near the bottom of the box B, in so doing the
coarsest and heaviest particles drop to the bottom of the box from whence they are
removed by means of an archimedean screw into the spout O by way of passage N,
this passage is made so long in a horizontal direction that the stive banks up in
front of the archimedian screw, and thus forms an air lock. The air freed of the
heavier particles passes in the direction of the arrows through orifices L into
entrance passage C. From this passage the air enters through numerous inlet
valves E into boxes P, the air descends in the direction of the arrows, through a
hole made in the bottom of each box and by a central sleeve Z through the centre
of the filter and surrounds the lower part of filter A. The dust or other matters
in the air adheres to the outside of filter while the pure air passing through the
filter enters, by way of orifices R and exit valves F, the exit passage D from
whence it is removed by exhaust fan I.
As the dust or other matter accumulates on the outside of the filter it drops
off into the bottom of the filter from whence it is removed by scraper G into
spout. H.
In course of time the filters, the sides of which are preferably of silk or flannel
would become clogged and would no longer act efficiently, the mechanism shown
in Figs: 3 and 4 is therefore used.
This mechanism consists in a series of chain wheels T made to revolve by chain
gearing as afterwards explained, each of these in turn actuate a worm U on its
shaft, which gearing into cam plate V causes the latter to revolve. As this cam
plate revolves the small roller throws the lever W from the position shown in
dots to that shown in full lines, the arm w of the lever W then brings the clutches X
into connection and motion is communicated to shaft Y. The tappet wheels a
then revolve and alternately elevate and depress the pivotted levers band c. These
levers actuate two rods, that is, the lever b actuates the rod d, and the lever c
actuates the rods e. To the end of lever W are attached the rods d' and e¹ which
are respectively connected to the entrance and exit valves E and F of the filter and
the rods de connected to the underside of the filter..
To effect the clearance of the filter the chain wheels T are set in motion by a
continuous chain turning in and out among them or preferably a wheel on each
axle is driven by a chain from the wheel on the axis immediately below by means
of chains S and through the intermediation of these wheels the rods d and e and
d' and e' are set in motion as above described. As the rods d', e¹, are actuated
they bring the entrance and exit valves to the positions shown in Figs. 5 and 6,
that is the valve E is closed to the entrance of any more dusty air and the valve F
is brought against the seating f, the opening g is then uncovered and allows the
entrance of air from fans J. This air traversing through the filters in a direction
opposite to that taken by the dusty air clears the filters of the adhering matter
being aided in so doing by the rods de which as they move raise and lower the
bottom of the filter, thus shaking its filtering surface.
The chain wheels T and their mechanism are so arranged that only one filter
can be operated on for cleaning at one time and when large numbers of filters
are used the mechanism is so regulated that the moment one filter is thrown
into work the next in course is thrown out for cleaning. By this means the

page_text: filtering is made uniform whereas in all other machines for this purpose that I
know of a large part of the filtering surface is periodically thrown out for
cleaning and consequently the working of the machine is made inefficient and
irregular.
Having now described my Invention and the best mode known to me of carrying
it into effect I claim under the Letters Patent:-
First The herein described preliminary stive or dust accumulator armed with
archimedean screw or other pushing apparatus and a passage sufficiently level and
long to form an air lock by the accumulation of dust in front of the pushing
apparatus for the purposes described.
Second In a dust collector the application of distinct valves for inlet and for
outlet with inlet and outlet fans arranged substantially as described.
Third. The application of a current of clean and preferably warm air caused to
enter and pass through the filter in a contrary direction to that taken by the dust
laden air while the filter is being shook so as to assist the cleaning substantially as
and in the manner described.
Fourth The manufacture of dust collectors having an intermittent shaking
apparatus and so arranged that the ordinary inlet and exit for dust laden air
shall be closed and an entering current of clean air admitted simultaneously with
the bringing into action of the intermittent shaking apparatus substantially as
described.
Fifth The arrangement or combination of air filtering apparatus having
numerous air filters in one apparatus, and cleaning mechanism arranged so as to
automatically clean each filter in succession there being always except when in the
act of changing the entire number of filters at work filtering except the one being
cleaned.
Sixth The manufacture of air filtering apparatus consisting of numerous
superimposed filters with their adjuncts-the whole arranged and constructed
substantially as herein described.
In witness whereof I the said Pieter Van Gelder have hereunto set my
hand and seal this Fourth day of August in the year of our Lord One
thousand eight hundred and eighty two.
P. YAN GELDEK, (LS.)