IMPROVEMENTS IN FILTER PRESSES."
Year: 1877

page_text: LETTERS PATENT to John Derbyshire, of Marsh Street, Longton, in the
County of Stafford, Engineer, for the Invention of "IMPROVEMENTS IN FILTER
PRESSES."
PROVISIONAL SPECIFICATION left by the said John Derbyshire at the
Office of the Commissioners of Patents on the 27th August 1877.
JOHN DERBYSHIRE, of Marsh Street, Longton, in the County of Stafford, Engineer.
"IMPROVEMENTS IN FILTER PRESSES."
This Invention has for its object improvements in filter presses.
Heretofore filter presses have been formed of a series of grooved wooden surfaces.
with filter bags between them, into which the liquid to be filtered has been forced
under pressure, and each grooved wooden surface has been surrounded at its edge
by a strong wooden rim. The rims of the adjacent wooden frames have butted one
against the other and formed supports for the extremities of the bags to rest against,
and they have been held between two end wooden frames, which have, been drawn
together by strong bolts.
In place of thus using grooved wooden surfaces to separate the filter bags one
from the other, I employ a corrugated sheet of brass, galvanized iron, or other metal
not liable to oxidize or corrode, and I retain this sheet metal at its edges in a metal
frame, the inner side edges of which are slotted to form a groove into which the
edges of the corrugated sheet metal are received; the slot is also cut entirely through
the bottom end of the frame to allow the sheet of metal to be slipped into its place,
and also to allow the liquid which flows from the filter bags to pass.down the
corrugations and escape at the bottom; the two ends of the frame have also
handles cast on or attached to them, by which they can be lifted and moved.
The end plates between which the several frames are received and held I also
form of metal; one of them is fixed in an upright position, above two supporting
beams, whilst the other plate can be moved to and from along these beams towards
or away from the fixed plate, and the two plates can be drawn and held together
177
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page_text: by bolts in the ordinary manner, so as to grip between them the frames which
contain the bags. The back of each end plate is strengthened by ribs across it at
intervals, and I also form the ribs with side flanges along their outer ends. Through
the top of the rim of each frame is a recess or recesses for the uniou pipe or pipes
attached to the fabric of the filter bag to lie in. Ordinarily I provide each bag with
two or more such union pipes in place of with one only, as heretofore, so as to give
a free supply of liquid to the bags when filtering. The ends of the pipes passing
from the bags are to be coupled up to branch pipes from a main supply pipe,
as is usual.
Filter presses constructed in the manner above described occupy less space than
filter presses as heretofore constructed. The moveable frames which support the filter
bags are also lighter, so that the press may more quickly and readily be taken
apart to empty the bags, and can also be more quickly set up again to filter a fresh
quantity of liquid. The frames will also be much more durable than those hereto-
fore used.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Derbyshire in the Great Seal Patent Office on the 26th
February 1878.
JOHN DERBYSHIRE, of Marsh Street, Longton, in the County of Stafford, Engineer.
"IMPROVEMENTS IN FILTER PRESSES."
This Invention has for its object improvements in filter presses.
Heretofore filter presses have been formed of a series of grooved wooden surfaces.
with filter bags between them, into which the liquid to be filtered has been forced
under pressure, and each grooved wooden surface has been surrounded at its edge
by a strong wooden rim. The rims of the adjacent wooden frames have butted one
against the other and formed supports for the extremities of the bags to rest against.
and they have been held between two end wooden frames, which have been drawn
together by strong bolts.
In place of thus using grooved wooden surfaces to separate the filter bags one
from the other, I employ a corrugated sheet of brass, galvanized iron, or other metal
not liable to oxidize or corrode, and I retain this sheet metal at its edges in a metal
frame, the inner side edges of which are slotted to form a groove into which the
edges of the corrugated sheet metal are received; the slot is also cut entirely through
the bottom end of the frame to allow the sheet of metal to he slipped into its place.
and also to allow the liquid which flows from the filter bags to pass down the
corrugations and escape at the bottom; the two ends of the frame have also handles
cast on or attached to them by which they can be lifted and moved.
The end plates between which the several frames are received and held I also
form of metal; one of them is fixed in an upright position, above two supporting
beams, whilst the other plate can be moved to and fro along these beams towards
or away from the fixed plate, and the two plates can be drawn and held together
by bolts in the ordinary manner, so as to grip between them the frames which
contain the bags. The back of each end plate is strengthened by ribs across it at

page_text: intervals, and I also form the ribs with side flanges along their outer ends. Through
the top of the rim of each frame is a recess or recesses for the union pipe or pipes
attached to the fabric of the filter bag to lie in. Ordinarily I provide each bag with
two or more such union pipes in place of with one only, as heretofore, so as to give
a free supply of liquid to the bags when filtering. The ends of the pipes passing
from the bags are to be coupled up to branch pipes from a main supply pipe, as is
usual.
Filter presses constructed in the manner above described occupy less .space than
filter presses as heretofore constructed. The moveable frames which support the
filter bags are also lighter, so that the press may more quickly and readily be taken
apart to empty the bags, and can also be more quickly set up again to filter a fresh
quantity of liquid. The frames will also be much more durable than those hereto-
fore used.
The Drawings hereunto annexed shew various views of a filter press constructed
according to my Invention.
Fig. 1 shews a plan view, and Figure 2 an end view of the press when closed.
Figures 3 and 4 shew similar views of the press when open.
Figure 5 is a front view, and Figure 6 a back view of the press.
Figure 7 shews a section, full size, of part of two adjoining frames where the pipe
by which the bag placed between the frames is to be filled passes out through
recesses in the frames.
Figure 8 shews, on a smaller scale, a section through one of the frames, shewing
the slot and grooves into which the corrugated plate is to be introduced.
Fig. 9 shews a transverse section taken through the corrugated plates of part
of two adjacent frames.
a are the frames; 6 are the corrugated metal plates, the edges of which are received
into grooves in the frames, as above described; the plates are retained by small
screws or pins, not shown in the Drawing; c, c, are two supporting beams, upon
which the frames rest when set up in place, and as shown at Figure 3; the frames
are formed with projections to come on either side of these beams; by this means
the frames are easily set up in correct position one behind the other; d, d, is a fixed
plate standing up at one end of the beams to serve as an abutment for the frames
to rest against: e, e, is the moveable plate which is held by long bolts f against the.
outermost frame when the press is closed. The way in which these plates are
formed with flanged strengthening ribs at the back is clearly shown by the Drawing.
The holes in the fixed plate through which the bolts of pass are made oval, so that
when the nuts upon them are slackened the lower bolts may slightly drop whilst
the upper ends can be somewhat lifted and slid back so as to be out of the way, as
shown at Figure 4. The moveable plate is thus left free to be turned down into
the position shown at Figure 4, and is then supported in a horizontal position, or
nearly so by legs e jointed to it, as shown, so that it may serve as a table or
support on to which the frames may be laid. The frames can then be laid one by
one on to this table, and the filtering bags or cloths in them opened out and emptied,
and the bags be either again folded down in the ordinary manner into the frame or
fresh ones put in their place.
The manner in which the filter cloths or bags are folded into the frames is to a
certain extent shown at Figure 3; it is however done in the ordinary way, so that
it is not necessary to give any description of it.
0
When all of the frames have thus been again got ready for use, they are stood up
one behind the other against the fixed plate d; the moveable plate is then turned
up so as to rest against the outermost frame, and is secured by the bolts f, as shown
at Figure 2. Fluid under pressure is then supplied to the interior of all the bags
through nozzles g on a moveable branch of a supply pipe h. To facilitate this I
employwashers i of vulcanized india-rubber, as shown in the full size view, Figure 7.
The smaller diameter of the washer fits a hole in the cloth or fabric, and passes out
through a circular opening formed by the meeting of two semicircular recesses in
the edges of two adjoining frames. When the frames have all been set up in place,

page_text: the moveable branch 1 of the supply pipe is brought down by the lever k, and the
filling nozzles upon it are caused to enter the flexible washers secured to the filter
bags or cloths. The lever handle is then held down by a screw nut ³ swivelled to
it, being screwed on to screw rods 7 carried by the moveable end plates, as shown
at Figure 5. The moveable branch is capable of sliding up and down on the supply
pipe, so that it can be raised or lowered, as described, by the lever 7.
As will be seen, there are two supply nozzles to each filter bag so as to give to it
a free supply of the liquid to be filtered. Each nozzle is furnished with a tap by
which the supply of liquid can be shut off, the main supply pipes are also
provided with taps for the same purpose.
.
Having thus described the nature of my Invention, and the manner of performing
the same, I would have it understood that I claim as my improvements in filter
.presses,-
First. The construction of the frames which are to retain the filter bags of filter
presses, substantially in the manner herein-before described.
Second. The construction of filter presses, substantially as herein-before described
and shown by the Drawings annexed.
In witness whereof, I, the said John Derbyshire, hereunto set my hand and
seal, this Twenty-second day of February, in the year of our Lord One
thousand eight hundred and seventy-eight.
JOHN DERBYSHIRE. (L.s.)