Improvements in Apparatus for Separating Dust from Air.
Year: 1885

page_text: Improvements in Apparatus for Separating Dust from Air.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings in the County of Middlesex 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 :-
This invention relates to improvements in that class of machines which are
employed in flour mills, factories, and other industrial establishments for separating
the dust from the air which is drawn from grinding mills, middlings purifiers,
grain cleaners, and other machines; the separation being effected by filtering the
dust-laden air through bags of flannel or other cloth. The object of the said
invention is to provide efficient means for keeping the filter cloth clear and free
from accumulated dust, and to remove the separated dust in a simple manner.
In the accompanying drawings,
Figure 1 is a side elevation of my improved dust collector, shewing one of the
filter bags elevated and the other lowered.
Figure 2 is a top view or plan of the machine.
Figure 3 is a vertical cross section of the machine.
Figure 4 is a longitudinal section of a portion of the machine drawn to a reduced
scale, shewing one bag lowered and the other elevated.
Figure 5 is a longitudinal sectional elevation of the pulleys and connecting parts
of the mechanism whereby the bags and valves are moved.
Figure 6 is a cross section on the line x, x Figure 1.
Figure 7 is a cross section on the line y, y Figure 1.
Figure 8 is a cross section on the line 2, 2, Figure 1.
Figure 9 is a detached sectional view shewing a device for jarring the bag as it
s raised and lowered.
Figure 10 is a vertical section of a modified construction of the bag.
Figure 11 is a top view or plan of the same.
Like letters of reference refer to like parts in the several figures.
A represents the stationary frame of the machine, A' the hopper shaped dust
eceptacles arranged in the lower part of the frame A side by side; A² the air
runk through which the dust-laden air is conducted to the machine, and a the
openings leading from the air trunk A' into the dust receptacles A¹
B represents the conveyor trough arranged lengthwise underneath the dust
eceptacles A¹, B¹ the conveyor screw arranged in the trough B, and b the openings
eading from the dust receptacles A¹ into the trough B.
CC represent the filter bags secured with their lower ends, to the dust
eceptacles A¹ so as to communicate therewith and having free upper ends which

page_text: can be lowered for reversing the bags and dislodging the dust which adheres to the
inner side of the same. CC represent open frames to which the upper ends of
the bags are secured and which are covered with filter cloth to increase the
separating area, & represents a band cord or chain attached to each frame C¹ and
running over a guide pulley d¹ for raising and lowering the bags.
e represents a horizontal driving shaft arranged lengthwise on the front side
of the machine and supported in bearings e¹ which are secured to the frame A.
E represents a band pulley mounted loosely on the shaft e and having one end of
the band d attached to its face, so that by turning the pulley in one or the other
direction the band d is wound upon the pulley or unwound therefrom, thereby
raising or lowering the bag, f represents a band, cord or chain attached to the
face of the pulley E on one side of the band d and running around the pulley in an
opposite direction. F is a weight attached to the lower end of the band ƒ and
adapted to counterbalance the larger portion of the weight of the bag. When the
pulley E is released the bag descends by gravity and the weight F is raised and
retards the downward movement of the bag. The face of the pulley E is prefer-
ably provided with projecting rims, as shewn, whereby the bands d and ƒ are
separately guided on the pulley.
G represents a band pulley mounted loosely on the shaft e on one side of the
pulley E and adjacent to the band d. g is a band secured with one end to the face
of the pulley G and provided at its opposite end with a weight g¹ which is
.sufficiently heavy to raise the bag quickly. The bag 9 runs around the pulley G
in the same direction in which the band fruns around the pulley E.
H represents an arm or carrier secured to the shaft e to rotate therewith in the
direction of the arrow in Figure 8 and provided with a pivotted pawl h, which
engages with a nose i on the hub of the pulley G in such manner as to cause the
pulley to rotate with the shaft e, thereby winding the band g upon the pulley G
and raising the weight gl. J. represents a stationary ring or circular frame
adjacent to the outer side of the pulley G and provided with an arm whereby it is
secured to the frame A concentric with the shaft e. j represents a stop secured to
the ring J and adapted to trip the pawl and disengage it from the nose i of the
pulley G, thereby disconnecting this pulley from the shaft e and permitting the
weight g to run down and rotate the pulley in a direction opposite to that in
which the shaft e rotates.
I represents a pawl pivotted to the inner side of the pulley G and engaging with
a nose on the hub of the pulley E in such manner as to cause the pulley E to
rotate with the pulley G, when the latter is rotated by the weight g¹ thereby
causing the bag to be elevated by the heavy weight attached to the pulley G
together with the light weight attached to the pulley E, both running down
simultaneously on the same side of the pulleys E and G. 7 represents a detent pawl
pivotted to the frame A and engaging in a notch in the rim of the pulley E in
such manner as to prevent the pulley from being rotated by the weight of the bag.
1 is a projection or cam formed on the rim of the pulley G in such a position as to
clevate the pawl and disengage it from the pulley E when the bag is required to
be lowered.
m represents a sliding valve which opens and closes the aperture a through
which the dust-laden air passes from the air spout A' into the dust receptacle A¹,
and n is a similar sliding valve whereby the aperture 6 leading to the conveyor
trough is opened and closed. The valves m and n move in inclined ways and are
made sufficiently heavy to descend by gravity, when released. The conveyor
valve n is arranged in the ways below the air spout valve m and is attached to
the latter by a slotted connection m¹ which permits the valve n to close before the
valve m has fully opened the opening a of the air spout. The closing movement
of the valve m is very quick, as it is produced by the descent of a weight P, while
its opening movement which is produced by the rotation of a pulley O in raising
the weight P, is comparatively slow in order to prevent a violent reaction on the
air currents in the purifiers or other machines with which the dust collector is

page_text: connected. On the downward movement of the valves the conveyor valve n
descends with the air spout valve m, thereby fully closing the conveyor aperture b
first and before the air spout opening a is fully opened, as the movement of
the air spout valve m continues after the valve n is closed as far as the slotted
connection m³ permits.
The pulley O, whereby the valves are operated, is connected with the upper
valve m by a cord o¹ running over a guide pulley o'. The pulley O is mounted
loosely on the shaft e on one side of the pulley E, and the cord of is so connected
with the pulley O that upon rotating the latter, in the direction to wind the
band o¹ upon the pulley, the valves m and n are raised. The pulley O is rotated
in this direction by the weight P which is attached to the pulley by a cord p in
such manner that the weight P in running down will unwind the cord p from the
pulley O and wind the cord o¹ upon the same. q is a detent pawl pivotted to the
frame A and engaging against a recessed shoulder q on the pulley O in such
manner as to prevent the pulley from being rotated by the weight P. Q is an
arm secured to the shaft e on one side of the pulley O and adapted to lift the
pawl out of engagement with the pulley when the weight P is required to run
down. The detent q is provided on its side with a nose qª which is lifted by the
arm Qin rotating the shaft e.
•
R represents an arm or carrier secured to the shaft e on one side of the pulley O
and provided with a pivotted pawl which engages with a nose formed on
the hub of the pulley O, so as to rotate the pulley in the direction in which
the weight P is raised. S is a ring or circular frame arranged on one side of the
pulley concentric with the shaft e and provided with an arm by which it is
secured to the frame A. 8 is a stop secured to the ring S in such a position as to
trip the pawl and disengage it from the pulley O when the weight P has been
elevated and the detent q has engaged with the pulley.
The shafte is rotated slowly by any suitable means, a speed of about one
revolution every two minutes being suitable for the devices represented in the
drawing. When the bag has been in its elevated position the predetermined
length of time, the arm Q lifts the detent q out of engagement with the pulley O,
whereby the weight P is permitted to run down and caused to rotate the pulley O
so as to wind up the cord o² and close the air-spout valve m and open the
conveyor valve n."
The blast is thus shut off from the bag preparatory to clearing
the same and the opening of the conveyor trough is opened to receive the
accumulated dust. The cam on the pulley G now lifts the detent pawl and
disengages the latter from the pulley E, whereby the upper end of the bag C' is
permitted to descend and the bag is reversed. The small weight F is at the same
time raised and retards the downward movement of the upper end of the bag,
which movement continues until the nose ¹ of the pulley E strikes the pawl k
of the pulley G. The pawl h of the carrier H is now tripped by the stop j and
disconnected from the nose i of the pulley G, thereby disconnecting the latter
from the shaft e and permitting the pulley to be rotated by the weight g¹. The
pulley G turns the pulley E by means of the pawl k and nose k¹, and the weight F
descends at the same time and assists in turning the pulley E in such manner as
to elevate the upper end of the bag C by the band d¹. This movement of the
pulley E continues until the upper end of the bag C has reached its highest
position and the bag has been fully distended. While the bag is being distended
the outer air flows into the bag and supplies the partial vacuum created in the
same, and in so doing assists in dislodging the dust particles which may adhere to
the inner side of the bag. The pawl r of the carrier R next engages with the
pulley O and rotates the latter in such direction as to raise the weight P and
unwind the cord o¹, thereby permitting the valves m and n to descend, thus closing
the conveyor valve n and opening the air spout valve m, so that the blast is again
admitted to the bag C. This movement of the pulley O continues until the pawl.r
is tripped by the stop 8. The bag remains elevated until the predetermined period
of time has passed, when the operations of raising the valves, lowering the bag,

page_text: raising, it and lowering the valves are repeated in the above described manner.
Several bags are connected with the same blast spout A' side by side, and each
is provided with separate mechanism for actuating the valves and the bag, but all
are driven by the same shaft e, and the actuating mechanisms of the several bags
are so timed that the air current is shut off from only one bag at a time.
By duplicating the actuating devices on diametrically opposite sides of the shaft e
the bag, can be dropped twice and through half the distance for every revolution of
the shaft. The band d is made of about half the ordinary length in this case.
་
In the construction represented in Figure 9, the pulley.to which the strap dis
attached is provided with a rim t having alternating projections and depressions
which oscillate a lever T. The latter bears upon the strap d and jars. the same,
thereby jarring the bag, which materially assists in dislodging or detaching the
dust which adheres to the bag..
:
In the modified construction represented in Figures 10 and 11, the bag. C is
provided with an inner auxilliary bag U. for the purpose of increasing the filtering
surface. The inner bag U is secured with its lower and narrow end to a plate or
bridge which is attached to the hopper A¹ and with its upper wide end to
the frame C. The latter is, constructed in this case with openings u¹ for the
escape of the air which filters through the inner bag U.
.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated
to me by my foreign correspondent I declare that what I claim is
First. In a dust collector, the combination with the air spout, of a dust receptacle
connected therewith by an aperture, a valve applied to said aperture and opened
and closed automatically, and a filter bag having its lower fixed end communicating
with said dust receptacle and having a movable upper end which is lowered to
detach the dust from the bag and deliver it into the dust receptacle, substantially
as set forth.
Second. In a dust collector, the combination with the air spout and the dust
receptacle provided with a dust discharge opening, of a filter bag having one end
rigidly secured and the other end movable, and a valye whereby the dust discharge.
opening is automatically opened and closed, substantially as set forth.
Third. The combination with the air spout and the dust receptacle provided
with a dust discharge opening, of the filter bag having one end rigidly secured and
the other end movable, a valve whereby the connection between the air spout and
the filter bag is automatically opened and closed, and a valve whereby the dust
discharge opening is automatically opened and closed, substantially as set forth.
Fourth. The combination with the air spout and dust receptacle, of. a filter bag
having its lower end rigidly secured and its upper end made movable, and a lifting
mechanism, substantially as described, attached to said movable end, whereby the
same is raised and lowered, substantially as set forth.
Fifth. The combination with the air spout and dust receptacle, of a filter bag
having a movable upper end, an air valve interposed between the air spout and
the dust receptacle, a dust discharge valve, and mechanism, substantially as
described, whereby said valves are automatically opened and closed, substantially
as set forth.
HASELTINE, LAKE & Co.,
For the Applicant.