Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to an automatic bag opening apparatus,
and method and more particularly to an apparatus and method for opening bags con-
taining material harmful to humans.
It has recently come to the public's attention that certain construc-
tion materials, e.g., asbestos, can cause severe respiratory problems when humans
are exposed to it.
To eliminate exposure from such building materials, it is advantageous
to open bags of such material (asbestos) automatically and to have the environ-
ment around the automatic bag opener continually evacuated to eliminate particles
of the material released during the bag opening operation from the area surround-
ing the automatic bag opener.
The principle object of the present invention is to provide an appara-
tus and method for automatically opening a bag of material.
In accordance with the present invention, there is provided an appara-
tus for automatically opening a bag comprising: (a) a frame, (b) a conveyor for
transporting the bag into the apparatus, (c) means operably associated with the
conveyor for automatically removing the bag from said conveyor and for supporting
and maintaining stationary said bag when said bag has reached a predetermined
position on said conveyor, wherein said removing and supporting means comprises
2Q a first table operably associated with said conveyor for removing, supporting and
maintaining stationary bags from said conveyor, and a second tab.le positioned
adjacent and rectilinearly aligned with said first table, and means for moving
said bag from said firs:t table to said second table, (d) means operab.ly associated
with the removing and supporting means:for cutting the bag, wherein said cutting
means:comprises at least one cutting wheel pivotally mounted to the apparatus and
adapted to contact s.aid b.ag when said hag is on aaid tahle, and (e) means operably
as.s~ci.~ated ~.ith b.~th s.aid ~emoying Rnd supporting ~eans. and the cutting meana for
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automatically gripping and moving said bag into and through said cutting means
and automatically releasing said bag after said bag has moved Lhrough said cut-
ting means.
In accordance with the present invention, there is further provided
a method for au~omatically opening a bag which comprises: (a) transporting the
bag on a conveyor, (b) automatically removing said bag from the conveyor, (c)
supporting said bag stationarily on a first table, (d) automatically gripping
said bag supported on the first table, (e) moving said bag rectilinearly from
said first table onto and across a second table aligned with the first table,
(f) cutting the bag while said bag is moving across said second table, (g) releas-
ing said bag, and (h) venting the area above both said first and second tables.
In drawings which illustrate the invention,
Figure l is a side elevational view, partially in phantom, of the auto-
matic bag opener apparatus of the present invention.
Figure 2 is a view taken along lines 2-2 of Figure l.
~ Figure 3 is an end view of the apparatus taken along lines 3-3 of
- Figure l.
Figure 4 is an enlarged elevational view of the bag gripping and moving
means and the drive mechanism associated therewith.
Figure 5 is a view taken along lines 5-5 of Figure 4.
Figure 6 is an enlarged end view of the bag gripping and moving means
of the present invention taken along lines 6-6 of Figure 4.
Figure 7 is a view of the hag gripping and moving apparatus of the
present invention, taken along line& 7-7 of Figure 6.
Fi~ures 8, 9, lO, ll, 12 and 13 are a series of schematic views illus-
trating the operation of the automatic bag opening apparatus of the present
inventi~n.
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The function of the apparatus of the present invention is to receive
bags of material and automatically open and remove the bagged material therefrom.
The present invention is specifically designed for use with bags containing
material which may be harmful to humans, e.g., asbestos.
Referring now to the drawings and particularly to Figure 1, there is
shown an automatic bag opener 50 of the present invention. The automatic bag
opener consists generally of a main frame 52 which includes vertical supports or
legs 54 and hori70ntal connecting members 56 and 58. Shafts 70 are rotably
mounted to the two side supports, by bearings 72, or the like.
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A plurality of sprockets 74 are rigidly mounted to shafts 70.
These sprockets rotate with the rotation of shafts 7U to convey bags of
material placed thereon into the apparatus. A suitable conventional drive
means, e.g., an electric motor, (not shown) drives shafts 70.
As illustrated in Figure 2, a vertically movable first table 80
is normally positioned below the upper~most periphery of sprockets 74' and
above shafts 70. This table contains apertures 82 through which sprockets
74', located within the boundary of the table, rotate. The structure of
table 80 permits the sprockets to engage and convey bags of material to
a position immediately above the table, as shown in Figure 10.
As previously stated, table 80 is vertically movable to a posi-
tion-above the outer-most periphery of the sprocket conveyor. The table is
moved vertically by any suitable conventional power source ~not shown) e.g.,
a hydraulic cylinder, etc. The power source is activated by limit switches,
shown in Figures 11 and 12. These switches, described hereinbelow, acti-
vate the power source for the table thereby raising the table from its
lower position seen in Figures 8 and 9, above sprockets 74' causing the bag
to be removed from the conveyor and supported on the table.
Prior to being completely removed from sprockets 74 of the
conveyor, the bag has traveled to a position above the first table so as to
contact limit swi~ch 420, (shown in Figure 11). This limit switch con-
trols the operation of the conveyor and stops the conveyor thereby stopping
the bag at this point.
The normal at rest position of the gripping and moving means is
illustrated in Figures 8 and 13. As shown in Figures 7, 8 and 9~ the
downwardly extending arms 96 of the gripping and moving means are adapted
to pivot upwardly around shaft 138 as indicated by arrow A, in Figure 7, to
permit an incoming bag of material to pass therebelow as it proceeds
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backward to begin the c~cle.
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The components of the gripping and moving means are illustrated,
specifically, in Figures 4, 5~ 6 and 7. A carriage 100 includes a trolley
lOl having a bottom plate 102 on which the horizontal moving power source
90 for the gripping and moving means is mounted. A housing 103, shown in
Figure 1, is mounted to the bottom plate and extends upwardly therefrom. This
housing encloses the electrical control components so that particles released
from opened bags will not interfere with the operation.
The horizontal drive consists of motor 104 of any suitable *ype,
e.g., an electric motor, etc. This motor is connected to a conventional
90 gear box 106 which has a horizontally disposed output shaft 108
extending theref~om. A sprocket 110 is mounted to shaft 108 so that rota-
tion of the shaft will be directly imparted to the sprocket. Two shafts
112 and 114 are rotatably mounted to plate 102 by means of brackets 115.
Pairs of gears 116 and 117 are mounted to either end of shafts 112 and 114,
~only one gear of each pair being shown). Also rigidly mounted to shaft 112
is sprocket 118. This sprocket has drive chain 120 positioned therearound,
while the other end of chain lZ0 is positioned around and driven by sprocket
110 .
Sprocket 118 is rotated through drive chain 120 thereby also rota-
ting shaft 112 and sprocket 116. Carriage 100 also includes a pair of rails
or tracks 122 having legs 124 mounted to and extending upwardly from main
frame members 56, only two of the four legs 124 are shown in Figure 1. The
rails 122 extend over the first table and through the automatic bag opening
apparatus. The rails have attached to the bottom surface a gear rack 126
over which gears 116 move. The rails also have a smooth upper surface 128
on which guide wheels 130 move. The wheels 130 have stub sha~ts 132 which
are rotatably mounted in bearing 134.
The trolley portion of carriage 100 is therefore supported by wheels
`-: 132 which are free to roll over the smooth top surface lZ8 o~ the rails. The
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motive force for the trolley comes from the ro~a~ion of driven sprockets 116,
mounted to driven shaft 112, through the lower notched portion 126 of the
rails.
A pair of clevises 135 are mounted by nuts and bolts or the like,
to the bottom surface of plate 102. Shaft 138 extends through and is free
to rotate within clevises 135. The center portion 139 of shaft 138 is flat-
tened, as shown in Figures 6 and 7.
Do~nwardly extending arms 96 are mounted to shaft 138. These arms
consist of two triangular-shaped end members 142 which are rigidly mounted
to shaft 138 by means of pins 143. Front plate 144 is secured ky welding
or the like to members 142 and extends vertically downwardly therefrom. The
front plate contains apertures lA5 and 146. As illustrated in Figure 6,
apertures 145 are positioned above apertures 146 A plurality of clevises
148 are mounted to the rear face 149 of front plate 144. Shaft 150 is
rotatable mounted in clevises 148. The shaft is secured within the clevises
by cotter pins 151 and 15~ which pass through the respective ends of shaft
150.
Guide brackets 154 and 156, respectively, are secured by screws
158 to front plate 144. These brackets contain guide members 159 which
retain and guide the vertlcal .. movement of plate 160. The rear ends 161
of guide members 159 are rigidly secured to a flat mounting plate 163
which is in turn rigidly secured to a J-shaped rear plate 165. Plate 160 is
generally rectangular in shape and contains two U-shaped openings 162 and 164,
respectively, in its lower portion. Stub shafts 166, 168, 170 and~172 extend
into the U-shaped openingsj~as illustrated in Figure 6. Guide brackets 174
and 176 are secured by screws 177 to plate 160. These brackets contain
guide portions 179 which retain and guide vertical plate 180 while retaining
the plates 160 and 180 in juxtaposition to each other, see ~igure 7
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Plate 180 has a generally U-shaped opening 181 positioned in its
bottom portion. This opening contains stub shafts 185 and 187 which extend
into the opening. Plate 180 also contains stub shafts 183 and 189 which
extend outwardl~ from the bottom sides of the plate towards members 142.
A dual action hydraulic cylinder 140 is mounted to both plates
160 and 180. The cylinder contains piston 145 onto which is threaded
clevis 182. This clevis is secured by lock nut 184 to the piston. The
clevis is mounted to plate 160 by means of mounting bracket 191. This
bracket has one end 187 rigidly secured by welding or the like, to plate
lO160. The other end 186 of bracket 191 con~ains an aperture which is aligned
with the ~perture in clevis 182 and through which shaft 188 passes. This
shaft rotatably secures the bracket to the clevis. A pair of cotter pins 189
pass through the respective ends of shaft 188 thereby maintaining the shaft
in the position illustrated in Figure 6.
A second mounting bracket 190 interconnects plate 18~ to barrel
portion 141 of the cyllnder. The second bracket is secured by bolts or the
like to both the barrel and plate 180 The upper portion of the barrel of
the cylinder is also mounted to plate 180 by welding or the like. The~upper
portion of plate 180 rests against the flat portion 13~ of shaft 138 and is
free to move vertically relative to the shaft.
Therefore, as illustrated in Figures 6 and 7 and discussed herein-
above, cylinder 140 is mounted to plates 160 and 180 which plates are mounted
for vertical movement relative to each other by means of brackets 154, 156, ~ -
174 and 176.
~As previously described, arms 96 contain shaft 150 which is
;rotatably mounted in clevis 148. Rotatably mounted to shaft 150 are a plural-
ity of arcuate shaped fingers 200~ 202, 204, 206 208, 210, 212 and 214. These
fingers are positioned along the length of shaft 150, as is shown in Figure 6.
Each of these ~ingers contain an aperture 201 therethrough. ~hese aper-
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tures are round in shape and are adapted to receive stub shafts 166J 183~
185, 168, 170, 187, 189 and 172 O~ plates 160 and 180. Shafts 166, 168, 170
and 172 of plate 160 are positioned through apertures contained in fingers
200, 206, 208 and 214. These fingers (200, 206 208 and 214) are disposed
on shaft 150 SO that the pointed end 220 of these fingers will be aligned
with the lower apertures 146 of plate 144. Shafts 183~ 185~ 187 and 189
are positioned through the apertures of fingers 202~ 204~ 210 and 212.
These are disposed on shaft 150 SO that pointed end 220 of the fingers will
be aligned with the upper apertures 145 of plate 144.
The solid line position of the fingers illustrated in Figure 7
depicts the normal "at rest" position of the fingers relative to each other.
In this position (i.e., at rest) the fingers are in their fully retracted
position. As cylinder 140 is activated, the piston 145 moves downwardly
to a predetermined position, as indicated by arrow B in Figures 6 and 7J
causing plate 160 and its associated stub shafts 166, 168, 170 and 172 to
move downwardly within apertures 201 of fingers 200~ 206, 208 and 214.
This movement of the shafts within the respective apertures causes the
pointed end 220 of these fingers to move through the lower openings 146 of
plate 144.
When the piston has moved downward through a predetermined stroke,
fingers 200~ 206, 208 and 214 are in the position illustrated in phantom
lines in Figure 7. Once the piston has reached the end of its predeter-
mined stroke the barrel portion 141 secured to plate 180 begins to move
upward, as illustrated by arrow C in Figures 6 and 7. This upward movement
of plate l80 will result in movement of shafts 183, 185, 187 and 189 UP-
wardly within the apertures in fingers 202, 204~ 210 and 212 thereby moving
these fingers from the solid line positions illustrated in Figure 7 to the
phantom line positions.
~; ~ It will be apparent from an examination of Figures 6land 7 that
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when fin~ers are fully retracted (i.e. at rest) their pointed ends are
abutted against the respective openings in plate 1~. This positioning is
accomplished by reversi-ng the flow of the fluid in cylinder 140 ~not shown)
which bias the piston and the cylinder into the position illustrated by
full lines in Figure 7.
Referring specifically to Figures ~ 9, 1 an~ 2, after an incoming
bag has been removed from the conveyor and is supported by first table 80
its ~the bag's) rear-most end R engaged by the fingers of the gripping and
moving means, it is then moved from table 8a onto a second table 250. This
second table is rigidly mounted to frame 52. The table is disposed at an
elevation equal to the raised height of the first table to facilitate move-
ment of the bag from the first to the second table. Table 250 contains a
plurality of rails 251. These rails support the bag of material as it is
moved over the table thereby further facilitating the movement of the bag of
material over the table.
As the bag of material proceeds over the second table, it contacts
a pair of cutting wheels 260. These wheels are rotatably mounted at the end
of arcuate shaped arms 261 and 262. These arms are biased by any suitable
means, into the center of table 250, as illustrated in Figures 2 and 3,
Cutting wheels 260 are driven by any suitable power source, e.g., a pneumatic
drive. The cutting wheels are overlapping and set at an angle to assure
cutting of the bag of material as it moves through the cutters. The end R
of the bag of material which is engaged by the fingers of the gripping and
moving means remains engaged to the fingers, even after the bag is cut and
opened.
The opened bag of material lS moved over table 250 until it reaches
a material receiving hopper 270. This hopper is positioned immediately at
the end of the second table 250.
-~` Positioned across the far side of hopper 270 is a cy~ nder 275
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over which the cut bag proceeds~ see Figure 13. The opened ends of the
bag are pulled across the cylinder to remove any ma~erial which may not have
fallen immediately into hopper 270. After the bag has moved over hopper
270 it is dropped into a second bag hopper 280. This second hopper is
positioned adjacent the material receiving hopper and directs the empty bags
of material into a bag bailing chamber 290. A hydraulic cylinder, the
piston of which is shown in Figures 1 and 2, acts to compress a predeter-
mined number of empty bags within chamber 290.
Mounted above the first and second tables and the material and
bag hoppers 270 and 280 is a hood 300. This hood encloses both of the
tables and both of the hoppers. A suitable vacuum pump,~not~ shown7~ is
connected to opening 31Q to evacuate the area above the tables and the
hoppers. It is important to maintain suction over these areas especially
when bags containing material harmful to humans ~e.g. asbestos~ are being
opened. Additional suction devices may be supplied at various positions
within the apparatus. For e~ample, in Figure ~, suction openings 320 and 330
are positioned on either side of the second table. These suction openings
are interconnected by suitable ducts (not shown) which ma~ be vented direct-
ly to the atmosphere or connected to the main suction duct connected to
opening 310.
The automatic operation of the automatic bag opener of the present
invention is illustrated schematically in Figures 8-13.
A bag of material is transported by a loading conveyor ~not shown)
to the sprocket conveyor. During the automatic operation the gripping and
moving means is in position P', shown in Figure 8, when a bag enters the
apparatus. The first bag continues on the sprocket conveyor until it con-
tacts switch 400 at which time the loading conveyor ~not shown) automatically
stops. ~hen the first bag moves off switch 400 the loading conveyor advances
a second bag until ît reaches switch 410. The first bag continues to move
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on the sprocket conveyor until it (~hc bag) contacts switch 420 which stops
the sprocket conveyor. Meanwhile~ the gripping and moving means is moving
from position P' to position Q along rail 122. During this movement the
car~iage of the gripping and moving means trips and resets switch 430. This
switch controls the operation of cylinder 140 of the gripping and moving
means. Wh~n the gripping and moving means reaches position Q, it trips
switch 440 which signals the raising of the first table, activates the
pneumatic drive of the cutting wheels, and reverses the horizontal drive
of the gripping and moving means.
On its return trip through the bag opener, as indicated by arrow
F, in Figure 8, switches 450 on trolley 101 is tripped by cam 455 which
signals the extension of the gripping finger. The gripping and moving
means continues through the apparatus over the second ~able 250 and the
bag is cut and opened. When the gripping and moving means reaches and
contacts switch 430 a signal is sent through the circuit to stop the cutting
wheels, to lower the first table, and to stop the carriage for a predeter-
mined amount of time over the hopper 270. After the predetermlned time
has elapsed, the gripping and moving means continues across rails 122 until
switches 450 contact cam 460. At this time the cylinder 140 is deactivated
withdrawing the gripping fingers and releasing the emptied bag of material
into hopper 28Q. When the gripping and moving means reaches switch 470 the
cycle repeats. Switch 470 also activates a counter which may be pre-set ?
to any number of trips, which will correspond to the number of empty bags
deposited in hopper 280. When the desired number of empty bags are in
hopper 280 a signal is generated by the counter activating the bailer
cylinder, the piston of which is shown in ~igures 1 and 2.
If the bag contains material harmful to humans, the vent may be
activated thereby venting the area above the automatic bag opener and remov-
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ing particles of the material which may be released during the bag opening
process from the immediate vicinity.
~ hile the preferred structure in which the principles of the
present invention have been incorporated is shown and described above, it is
to be understood that the invention is not to be limited to the particular
details, shown and described above, but tha~J in factl widely different
means may be employed in the practice of the broader aspects of the inven-
tion.
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