U.S. patent number 3,673,759 [Application Number 05/030,681] was granted by the patent office on 1972-07-04 for bag hanger apparatus.
This patent grant is currently assigned to Bemis Company, Inc.. Invention is credited to Richard H. Ayres, Gaylerd M. Lieder.
United States Patent |
3,673,759 |
Ayres , et al. |
July 4, 1972 |
BAG HANGER APPARATUS
Abstract
For filling bags, a V-trough conveyor to receive a filled bag
from a hopper assembly, a longitudinally elongated bag magazine to
hold spaced stacks of bags in an inclined condition, a first piston
cylinder combination to reciprocate vacuum cups and a break rod to
abut against one bag side wall and to partially open the bag mouth
as said cups and rod are retracted, a second piston cylinder
combination to rotate the first combination between a bag pick up
position and a hopper assembly transfer position and a third piston
cylinder combination to relatively move a bag clamp and a hopper
jaw from a hopper jaw closed position to receive a partially opened
bag from the cups when the second combination is in the transfer
position and a bag release position.
Inventors: |
Ayres; Richard H. (Minneapolis,
MN), Lieder; Gaylerd M. (Minneapolis, MN) |
Assignee: |
Bemis Company, Inc.
(Minneapolis, MN)
|
Family
ID: |
21855452 |
Appl.
No.: |
05/030,681 |
Filed: |
April 22, 1970 |
Current U.S.
Class: |
53/459; 53/386.1;
53/573; 198/468.4; 198/597; 271/91 |
Current CPC
Class: |
B65B
43/26 (20130101); B65B 43/18 (20130101); B65B
39/08 (20130101) |
Current International
Class: |
B65B
39/00 (20060101); B65B 39/08 (20060101); B65B
43/00 (20060101); B65B 43/18 (20060101); B65B
43/26 (20060101); B65b 043/18 (); B65h 003/08 ();
B65g 043/08 () |
Field of
Search: |
;53/190,386,29
;214/1BV,8.5D ;271/26 ;294/65 ;198/106 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Condon; Theron E.
Assistant Examiner: Abrams; Neil
Claims
What is claimed is:
1. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a longitudinal elongated frame, a plurality of
vacuum cups including a first vacuum cup and a second vacuum cups,
first means for applying a vacuum to said cups and alternately
discontinuing the application of vacuum to the cups, second means
for abutting against the bag side wall intermediate the bag mouth
and the opposite end thereof, third means for mounting the vacuum
cups and second means to be engageable with said side wall and
moving the vacuum cups to act in cooperation with the second means
to at least partially open the bag mouth as the cups and second
means are moved away from the magazine, fourth means for mounting
the third means and moving the third means between a first position
that the vacuum cups and second means are substantially spaced from
the bags on the bag magazine, a second position that the vacuum
cups engage the side wall of a bag in a flat folded condition on
the magazine, and a third position that the bag gripped by the
vacuum cups in at least a partially opened condition has the hopper
jaws extended into the bag mouth, and fifth means for controlling
the application of vacuum by the first means to apply the vacuum to
the cups prior to the cups being moved to the second position and
discontinue the application of vacuum after the cups have been
moved from the second position to the third position, said third
means including fifth means for mounting the second means and first
and second cups for limited movement relative one another,
resiliently retaining said cups and second means in a datum
condition relative one another and mounting the first cup relative
the second means in a position engageable with said side wall
intermediate the second means and the bag mouth and the second cup
in a position relative the second means in a position engageable
with said side wall intermediate the second means and the bag
opposite end.
2. The apparatus of claim 1 further characterized in that the
fourth means comprising a first piston cylinder combination having
an elongated cylinder and a piston rod mounting the third means for
reciprocating the third means between a retracted position and an
extended position relative the cylinder, and sixth means mounting
the cylinder on the frame and moving the cylinder between a
position that the cylinder extends toward the magazine and a second
position that the cylinder extends generally in a direction toward
the hopper assembly.
3. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a longitudinal elongated frame, a plurality of
vacuum cups, first means for applying a vacuum to said cups and
alternately discontinuing the application of vacuum to the cups,
second means for abutting against the bag side wall intermediate
the bag mouth and the opposite end thereof, third means for
mounting the vacuum cups and second means to be engageable with
said side wall and moving the vacuum cups to act in cooperation
with the second means to at least partially open the bag mouth as
the cups and second means are moved away from the magazine, fourth
means for mounting the third means and moving the third means
between a first position that the vacuum cups and second means are
substantially spaced from the bags on the bag magazine, a second
position that the vacuum cups engage the side wall of a bag in a
flat folded condition on the magazine, and a third position that
the bag gripped by the vacuum cups in at least a partially opened
condition has the hopper jaws extended into the bag mouth, and
fifth means for controlling the application of vacuum by the first
means to apply the vacuum to the cups prior to the cups being moved
to the second position and discontinue the application of vacuum
after the cups have been moved from the second position to the
third position, the third means including a transverse first pivot
member, sixth means for mounting the pivot member on the fourth
means to extend generally parallel to the marginal edges that
define the bag mouths of the bags on the bag magazine, elongated
seventh means having one end portion pivotally mounted on the pivot
member and an opposite end portion mounting a first vacuum cup a
greater distance from the pivot member than the second means,
eighth means connected to the seventh means for resiliently urging
the seventh means to pivot about the pivot member in one angular
direction and limit the pivotal movement of the seventh means in
said one angular direction to a preselected position.
4. The apparatus of claim 3 further characterized in that the third
means includes an elongated member having one end portion mounted
on the sixth means and an opposite end portion on the opposite side
of the pivot member from the first vacuum cup and ninth means for
mounting a second vacuum cup on said elongated member opposite end
portion.
5. The apparatus of claim 4 further characterized in that the
second means includes an elongated break member parallel to the
pivot member and tenth means for mounting the break member on the
pivot member and resiliently urging the break member toward and in
engagement with the bags on the bag magazine when the fourth means
has moved the third means to its second position and when the
fourth means is in the first position and no bag is being gripped
by the cups to a given position relative the pivot member.
6. The apparatus of claim 5 further characterized in that the sixth
means includes a second pivot member parallel to the fist pivot
member, said elongated member first end portion being pivotally
mounted on said second pivot member and that the third means
includes means for limiting the angular movement of the elongated
member in one direction to a given position and eleventh means
connected to at least one of the second vacuum cup and elongated
member for resiliently retaining the elongated member in the last
mentioned given position.
7. The apparatus of claim 6 further characterized in that the ninth
means includes a third pivot member mounted on the elongated member
opposite end portion, that said second vacuum cup has a tubular
portion that has one side thereof pivotally mounted on said third
pivot member and a diametric opposite side having the eleventh
means connected thereto, said eleventh means comprising an
elongated spring.
8. The apparatus of claim 7 further characterized in that the tenth
means mounts the break member generally between the first and
second vacuum cups and that the third means includes an elongated
control arm member having one end portion fixedly joined to the
seventh means and an opposite end portion abuttable against a bag
on the opposite side of the first pivot member from the first
vacuum cup in the fourth means second position to hold the seventh
means away from the preselected position, said seventh means
including an elongated first vacuum cup mounting member having a
first end portion fixedly attached to said control arm member.
9. The apparatus of claim 8 further characterized in that the
fourth means includes elongated twelfth means for reciprocating the
sixth means along the elongated axis thereof between an extended
position and a retracted position, said axis extending generally
perpendicular to the bags on the bag magazine in the third means
second position, that the sixth means has an advanced surface
portion extending more remote from the twelfth means in the
direction of extension thereof that the remainder of the sixth
means, and that the said given positions for the break member and
second vacuum cup are on the opposite side of a plane perpendicular
to said axis and through the advance surface portion from the
twelfth means.
10. The apparatus of claim 9 further characterized in that the
preselected position of said first vacuum cup is on the same side
of said plane as the twelfth means.
11. The apparatus of claim 7 further characterized in that the bag
magazine includes a magazine frame, a pair of transversely spaced
rolls mounted by the frame in parallel relationship at a
substantially inclined angle to the horizontal, a conveyor belt
mounted by said rolls and driven by at least one of said rolls,
said belt having an upper run of a length to have several spaced
stacks of bags placed thereon with the bag side walls extending
generally parallel to the upper run, said upper run having a lower
edge, a transversely elongated bottom wall fixedly mounted on the
magazine frame adjacent the lower edge to extend generally parallel
to the upper run and twelfth means for driving one of said rolls in
an angular direction to move the stack of bags into underlying
relationship to the vacuum cups in the third means first position,
the magazine frame having one portion underlying the vacuum cups in
the third means first position.
12. The apparatus of claim 11 further characterized in that the bag
magazine includes an end wall member mounted on the magazine frame,
said end wall member having a generally vertical portion in
overhanging relationship to the upper run, extending generally
perpendicular to the upper run and the bottom wall, and located in
a position to limit the movement of a stack of bags on the upper
run to position to be picked up by the vacuum cups, and that the
control means includes means for sensing the absence of bags
adjacent the end wall vertical portion and then automatically
actuating the drive means for a period of time that the upper runs
move a stack of bags adjacent said end wall vertical portion.
13. The apparatus of claim 12 further characterized in that the
angle of inclination of the rolls is about 20.degree. to
30.degree..
14. For grippingly engaging a side wall of a paper bag in a flat
folded condition on a bag magazine, transferring the gripped bag to
a hopper spout assembly having openable jaws and at least partially
opening the bag mouth portions sufficiently during the transfer
operation to have the hopper spout assembly jaws in a closed
condition extendable into the at least partially opened bag mouth,
bag transferring apparatus comprising a longitudinally elongated
frame, a transverse shaft rotatably mounted on the frame, operable
bag pick up mechanism for grippingly engaging one side wall of a
bag on the bag magazine and at least partially opening the bag
mouth as the gripped side wall is moved, said bag pick up mechanism
including means for bending said side wall about axes generally
parallel to the bag mouth to at least partially open the bag mouth
as the gripped side wall is being moved away from the magazine,
operable first means mounted on the frame to rotate the shaft
between a bag pick up position and a bag transfer position,
operable elongated second means mounted on the shaft to rotate
therewith for mounting the bag pick up mechanism and moving the bag
pick up mechanism relative the shaft between a first position to
pick up a bag when the shaft is in its bag pick up position and a
second position more closely adjacent the shaft than said first
position, and control means for operating the first means to move
the shaft from the bag transfer position to the bag pick up
position, the second means to move said pick up mechanism from
adjacent its second position to its first position and then back
toward its second position while the shaft is in the bag pick up
position, and then the first means to move the shaft from its bag
pick up position toward its bag transfer position and to operate
the bag pick up mechanism to grippingly engage the bag side wall of
the bag on the magazine when both the shaft is in its bag pick up
position and the bag pick up mechanism is in its second position
and to release the gripping engagement with the picked up bag when
the first means has been operated to move the shaft from its bag
pick up position to its bag transfer position.
15. The apparatus of claim 14 further characterized in that the
hopper assembly has bag clamps and means for mounting the bag
clamps and bag jaws for relative movement between a bag clamped,
jaw open third position and a bag clamp open, jaw closed fourth
position, and that there is provided operable third means on the
frame for relatively moving the bag clamps and jaws between the
third and fourth positions and that the control means includes
means for operating the third means to the fourth position while
the shaft is out of the bag transfer position and the second means
to move the pick up mechanism to its first position while the shaft
is being operated from the bag pick up position to the bag transfer
position.
16. For grippingly engaging a side wall of a paper bag in a flat
folded condition on a bag magazine, transferring the gripped bag to
a hopper spout assembly having openable jaws and at least partially
opening the bag mouth portion sufficiently during the transfer
operation to have the hopper spout assembly jaws in a closed
condition extendable into the at least partially opened bag mouth,
the hopper assembly having bag clamps and means for mounting the
bag clamps and bag jaws for relative movement between a bag
clamped, jaw open third position and a bag clamp open, jaw closed
fourth position, and operable third means on the frame for
relatively moving the bag clamps and jaws between the third and
fourth positions, bag transferring apparatus comprising a
longitudinally elongated frame, a transverse shaft rotatably
mounted on the frame, operable bag pick up mechanism for grippingly
engaging one side wall of a bag on the bag magazine and at least
partially opening the bag mouth as the gripped side wall is moved,
operable first means mounted on the frame to rotate the shaft
between a bag pick up position and a bag transfer position,
operable elongated second means mounted on the shaft to rotate
therewith for mounting the bag pick up mechanism and moving the bag
pick up mechanism relative the shaft between a first position to
pick up a bag when the shaft is in its bag pick up position and a
second position more closely adjacent the shaft than said first
position, and control means for operating the first means to move
the shaft from the bag transfer position to the bag pick up
position, the second means to move said pick up mechanism from
adjacent its second position to its first position and then back
toward its second position while the shaft is in the bag pick up
position, and then the first means to move the shaft from its bag
pick up position toward its bag transfer position and to operate
the bag pick up mechanism to grippingly engage the bag side wall of
the bag on the magazine when both the shaft is in its bag pick up
position and the bag pick up mechanism is in its second position
and to release the gripping engagement with the picked up bag when
the first means has been operated to move the shaft from its bag
pick up position to its bag transfer position, the control means
including means for operating the third means to the fourth
position while the shaft is out of the bag transfer position and
the second means to move the pick up mechanism to its first
position while the shaft is being operated from the bag pick up
position to the bag transfer position, and the bag pick up
mechanism including a pair of transversely spaced vacuum cups for
gripping the bag side wall adjacent the bag mouth and a third
vacuum cup for gripping the bag side wall further remote from the
bag mouth than the pair of cups, said cups having rim portions for
forming a fluid seal with a bag, a transverse break member between
the pair of cups and third cup, fourth means for mounting the cups
and break member on the second means for movement relative one
another, and fifth means connected to the fourth means and the cups
and the break member for resiliently urging the break member and
one of the pair of cups and the third cup to positions more closely
adjacent the bags on the bag magazine than the other of said pair
of cups and third cup when the shaft is in the bag pick up position
and the bag pick up mechanism is in the second position while
permitting the vacuum cups and the break member moving to positions
that the vacuum cup rim portions and break member are closely
adjacent a plane that is generally parallel to the bags on the bag
magazine.
17. The apparatus of claim 16 further characterized in that the bag
magazine includes a magazine frame, an endless conveyor belt having
a horizontally, transversely elongated upper run of a length many
times greater than the width of a bag, sixth means for mounting the
belt on the frame and drivable moving the belt about axes
substantially inclined to the horizontal, said upper run having an
upper edge and a lower edge, and a bottom wall mounted on the
magazine frame adjacent the belt lower edge to extend generally
perpendicular to the upper run and being elongated in the direction
of elongation of the upper run.
18. The apparatus of claim 17 further characterized in that there
is provided seventh means for driving the sixth means for driving
the belt to move the upper run in a given direction, that the bag
magazine includes an end wall mounted on the magazine frame in
overhanging relationship to one end portion of the upper end to
limit the movement of stacks of bags on the upper run in the last
mentioned direction.
19. The apparatus of claim 18 further characterized in that control
means includes means for actuating the seventh means to drive the
sixth means to move the upper run when no bags are adjacent the end
wall and discontinue the actuation of the seventh means when bags
are adjacent the end wall and preventing the first means being
operated to move the shaft from the bag pick up position to the bag
transfer position while the seventh means is actuated.
20. For grippingly engaging a side wall of a paper bag in a flat
folded condition on a bag magazine, transferring the gripped bag to
a hopper spout assembly having openable jaws and at least partially
opening the bag mouth portions sufficiently during the transfer
operation to have the hopper spout assembly jaws in a closed
condition extendable into the at lease partially opened bag mouth,
bag transferring apparatus comprising a longitudinally elongated
frame, operable bag pick up mechanism for grippingly engaging one
side wall of a bag on the bag magazine and at least partially
opening the bag mouth as the gripped side wall is moved, openable
first means mounted on the frame to rotate the shaft between a bag
pick up position and a bag transfer position, operable elongated
second means mounted on the shaft to rotate therewith for mounting
the bag pick up mechanism and moving the bag pick up mechanism
relative the shaft between a first position to pick up a bag when
the shaft is in its bag pick up position and a second position more
closely adjacent the shaft than said first position, and control
means for operating the first means to move the shaft from the bag
transfer position to the bag pick up position, the second means to
move said pick up mechanism from adjacent its second position to
its first position and then back toward its second position while
the shaft is in the bag pick up position, and then the first means
to move the shaft from its bag pick up position toward its bag
transfer position and to operate the bag pick up mechanism to
grippingly engage the bag side wall of the bag on the magazine when
both the shaft is in its bag pick up position and the bag pick up
mechanism is in its second position and to release the gripping
engagement with the picked up bag when the first means has been
operated to move the shaft from its bag pick up position to its bag
transfer position, the bag pick up mechanism including first and
second vacuum cups transversely spaced from one another, a
transverse break member, a third vacuum cup, each of said cups
having a rim portion for abutting against a bag, third means
mounting the first and second cups and break member for angular
movement about a first transverse axis, resiliently urging the
break member and the first and second cups in opposite angular
directions and limiting the angular movement of the break member
and first and second cups to datum positions, and elongated fourth
means for mounting the third vacuum cup generally on the opposite
side of the break member from the first and second cups, said third
and fourth means mounting the cups and break member to have the rim
portions and the break member to abut the bag side wall when the
shaft is in the bag pick up position and the second means has been
operated to move said pick up mechanism to the first position, and
said control means including means for applying and alternately
discontinuing the application of vacuum to the cups.
21. The apparatus of claim 20 further characterized in that the
third means includes a transverse pivot member, mounting means
pivotally mounted on the pivot member and having one end portion
for mounting the first and second vacuum cups on the opposite side
of the pivot member from the break member, fifth means connected to
the mounting means and extending on the opposite side of the pivot
member from the first and second cups for abutting against the bag
side wall as the second means is operated to move the pick up
mechanism from its second position to its first position when the
shaft is in the bag pick up position to move the mounting means to
move the first and second cups about the pivot member in one
angular direction and resiliently urge the mounting means to move
the first and second cups to move in an angular direction opposite
said one angular direction.
22. The apparatus of claim 21 further characterized in that fourth
means includes sixth means for mounting the third vacuum cup for
limited movement relative the pivot member between a third position
and a fourth position more closely adjacent the pivot member than
the third position and resiliently urging the third vacuum cup to
the third position.
23. The apparatus of claim 22 further characterized in that the
sixth means includes a mounting member, an elongated arm member
having one end portion mounted on the mounting member for pivotal
movement about a second transverse axis parallel to the pivot
member and an opposite end portion mounting the third vacuum cup
for pivotal movement about a third transverse axis, a stop member
connected to the arm member to limit the pivotal movement of the
arm member about the second transverse axis in one direction to a
limit position, and resilient means connected to third vacuum cup
and the mounting member to pivot the arm member about the second
transverse axis in the one direction and the third vacuum cup about
the third transverse axis to its third position when the arm member
is in its limit position.
24. The apparatus of claim 20 further characterized in that the
control means includes means for automatically applying a vacuum to
said cups as the first means has moved the shaft from the bag
transfer position toward and closely adjacent the bag pick up
position and fifth means to automatically initiate the operation of
the second means to move the bag pick up mechanism from its first
position to its second position upon the rim portions abutting
against the side wall of a bag on the bag magazine.
25. The apparatus of claim 24 further characterized in that the
fifth means includes means to automatically recycle the operation
of the second means to move the bag pick up mechanism between the
first and second positions upon the bag pick up mechanism moving
from its first position to its second position when one of the cups
in returning the bag pick up mechanism to its second position is
out of fluid sealing engagement with the bag side wall and block
operation of the first means to move the shaft from the bag pick up
position to the bag transfer position until all the cups are in
fluid sealing engagement with the bag side wall.
26. The apparatus of claim 24 further characterized in that the
control means includes means for applying air under pressure to the
vacuum cups as the first means moves the shaft from the bag
transfer position to the bag pick up position and discontinue the
application of air under pressure through the cups prior to the
shaft moving to the bag pick up position.
27. The apparatus of claim 26 further characterized in that the
second means includes a two way piston cylinder combination having
a cylinder keyed to said shaft and a piston rod to move the pick up
mechanism between the first and second positions, and that the
control means includes valve means operable between a first
position to apply air to one end of the cylinder to operate the
piston rod to its first position and a second position to apply air
to the opposite end of the cylinder to operate the piston rod to
its second position, and that the vacuum applying means includes a
source of vacuum, first vacuum lines for connecting the source of
vacuum to said cups, a control valve in said first vacuum lines to
block the application of vacuum from the source to the cups and
alternately fluidly connect the source of vacuum to said cups, a
second vacuum line in fluid communication with the first vacuum
lines between the control valve and the cups and fluidly connected
to the valve means for applying a vacuum thereto to operate the
valve means to its second position and a check valve in the second
line to block the application of vacuum through the second line to
the valve means until a substantial negative pressure has built up
in the first lines.
28. The apparatus of claim 27 further characterized in that the
control means includes fifth means to operate the control valve to
fluidly connect the source to the cups when the shaft is in the bag
pick up position and to block the application of vacuum to the cups
after the shaft has been moved from the bag pick up position to the
bag transfer position, and that there is provided means in the
second line between the check valve and the valve means to block
the application of vacuum to the valve means when the shaft is
moved from its first position.
29. The apparatus of claim 28 further characterized in that the
first means includes a second two way piston cylinder combination
having a cylinder pivotally connected to the frame and a piston rod
connected to the shaft to rotate the shaft as the piston rod is
moved between an extended position and a retracted position, that
the hopper assembly includes bag clamps and means mounting the bag
clamps and jaws for relative movement between a jaw closed, bag
clamp open fifth position and a jaw open, clamp closed sixth
position and that there is provided a third two way piston cylinder
combination for relatively moving clamps and jaws between the fifth
and sixth position and that the control means includes means to
operate the third combination to relatively move the clamps and
jaws to their sixth position as the shaft is moved closely adjacent
its bag transfer position.
30. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening the bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a frame, bag pick up mechanism having a
plurality of vacuum cups for abutting-against a bag on the bag
magazine to grip a bag on the magazine and at least partially open
the bag mouth as the bag is removed from the magazine, operable
reciprocal first means for moving the bag pick up mechanism between
an extended first position and a retracted second position,
operable second means mounted on the frame for mounting the first
means and moving the first means between a third position that the
bag pick up mechanism in its first position abuts against a bag on
the magazine and a fourth position that the first means is adjacent
the hopper assembly, and control means for operating the second
means to move the first means from the fourth position to the third
position, the first means to move the pick up mechanism from
adjacent its second position to its first position and then back
toward its second position when the first means is in its third
position, then operate the second means to move the first means
from its third position to its fourth position, and operate the bag
pickup mechanism to grippingly engage the bag side wall when both
the first means is in its third position and the bag pick up
mechanism is in its first position and to release the gripped bag
after the first means has been operated from the third position to
its fourth position, the control means including a source of
vacuum, and third means for automatically applying a vacuum to said
cups after the second means moves the first means from its fourth
position toward the third position and fourth means to
automatically initiate the operation of the first means to move the
bag pick up mechanism from the first position to the second
position, said fourth means including means to automatically
recycle the operation of the bag pick up mechanism between the
first and second positions upon the bag pick up mechanism moving
from its first position to its second position when one of the cups
in the return of the bag pick up mechanism to its second position
is out of fluid sealing engagement with the bag side wall and block
the operation of the second means from the third position to the
fourth position until all cups are in fluid sealing engagement with
the bag side wall.
31. The apparatus of claim 30 further characterized in that the
first means includes a two way piston cylinder combination having a
piston rod mounting the bag pick up mechanism and in an extended
position relative the cylinder positioning the bag pick up
mechanism at the first position and in a retracted position
relative the cylinder, positioning the bag pick up mechanism at the
second position.
32. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening the bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a frame, bag pick up mechanism having a
plurality of vacuum cups for abutting against a bag on the bag
magazine to grip a bag on the magazine and at least partially open
the bag mouth as the bag is removed from the magazine, operable
reciprocal first means for moving the bag pick up mechanism between
an extended first position and a retracted second position, the
first means includes a two way piston cylinder combination having a
piston rod mounting the bag pick up mechanism and in an extended
position relative the cylinder positioning the bag pick up
mechanism at the first position and in a retracted position
relative the cylinder, positioning the bag pick up mechanism at the
second position, operable second means mounted on the frame for
mounting the first means and moving the first means between a third
position that the bag pick up mechanism in its first position abuts
against a bag on the magazine and a fourth position that the first
means is adjacent the hopper assembly, and control means for
operating the second means to move the first means from the fourth
position to the third position, the first means to move the pick up
mechanism from adjacent its second position to its first position
and then back toward its second position when the first means is in
its third position, then operate the second means to move the first
means from its third position to its fourth position, and operate
the bag pick up mechanism to grippingly engage the bag side wall
when both the first means is in its third position and the bag pick
up mechanism is in its first position and to release the gripped
bag after the first means has been operated from the third position
to its fourth position, the control means including a source of
vacuum, first vacuum lines for connecting the source of vacuum to
said cups, a control valve in said first lines for permitting the
application of vacuum from said source to said cups when the first
means is operated from its fourth position to its third position
and also when the first means is in its third position, and to
discontinue the application of vacuum to said cups after the first
means has moved to its fourth position, the control means including
valve means operable between a first position for applying air
under pressure to one end of the cylinder to move the piston rod to
its extended position and a second position for applying air under
pressure to the other end of the cylinder to move the piston rod to
its retracted position, a second vacuum line fluidly connected to
the first vacuum lines between the control valve and the vacuum
cups and to the valve means for applying a vacuum thereto to
operate the valve means to the valve means second position, and
third means in the second line to block the application of vacuum
therethrough to the valving means until the negative pressure
therein has reached a preselected measurement, and permit the
application of vacuum to the valving means after the negative
pressure has reached said preselected measurement.
33. The apparatus of claim 32 further characterized in that the
control means includes a vacuum limit switch in the second line
between the third means and the valving means for blocking the
application of vacuum to the valving means after the first means
has been operated from the third position toward the fourth
position, and means for operating the valving means to its first
position after the first means has been operated from the fourth
position to the third position.
34. The apparatus of claim 33 further characterized in that hopper
assembly includes bag clamps, means for mounting the bag clamps and
jaws fro relative movement between a jaw closed, clamp open fifth
position and a jaw open, clamp closed sixth position and operable
fourth means mounted on the frame for relatively moving the jaws
and clamps between the fifth and sixth positions, and that the
control means includes fifth means for operating the fourth means
to relatively move the jaws and clamps to the sixth position to
receive the partially open bag from the bag pick up mechanism when
the bag pick up mechanism is in its first position and the first
means is in the fourth position, and as the first means is operated
to its fourth position, open the received bag to receive a charge
from the hopper assembly and support the opened bag, and to operate
the control valve to block the application of vacuum through the
first lines after the jaws and clamps are in the sixth
position.
35. The apparatus of claim 34 further characterized in that there
is provided a conveyor beneath the hopper assembly for receiving a
charged bag therefrom and moving the charged bag away from beneath
the hopper assembly, and that the control means includes means
mounted on the conveyor for blocking actuation of the second means
to move the first means from the third position to the fourth
position until the conveyor has moved the charged bag a preselected
distance away from beneath the hopper assembly, and as the charged
bag moves said preselected distance, permit actuation of the second
means, and that the fifth means includes means operated by the
second means moving the first means from the fourth position to the
third position to operate the fourth means to move the jaws and
clamps to the fifth position to release the charged bag.
36. In a method of transferring a flat folded tubular paper bag
having side walls and a bag mouth from a bag magazine to a hopper
assembly comprising the steps of pneumatically grippingly engaging
one bag side wall at a pair of spaced locations adjacent the bag
mouth and at a third location more remote from the bag mouth than
said pair of locations and removing the bag that is gripped at the
three locations from the magazine including bending the gripped
side wall about axes generally parallel to the bag mouth and
intermediate the pair of gripped locations and the third location
for separating the side wall portion that is gripped at said two
locations from the adjacent side wall portion of the other bag side
wall to at least partially open the bag mouth as the bag is removed
from the magazine and contacting the gripped side wall at said axes
as it is being bent.
37. The method of claim 36 further characterized in that the
removing step including initially moving the bag portion at the
pair of gripped locations away from the magazine prior to the side
wall portions at the third location.
38. In a method of transferring a flat folded tubular paper bag
having side walls and a bag mouth from a bag magazine to a hopper
assembly comprising the steps of pneumatically grippingly engaging
one bag side wall at a pair of spaced locations adjacent the bag
mouth and at a third location more remote from the bag mouth that
said pair of locations, bending the gripped side wall about axes
generally parallel to the bag mouth and intermediate the pair of
gripped locations and the third location for separating the side
wall portion that is gripped at said two locations from the
adjacent side wall portion of the other bag side wall to at lease
partially open the bag mouth, and removing the gripped bag from the
magazine, the removing step including initially moving the bag
portion at the pair of gripped locations away from the magazine
prior to the side wall portion at the third location and the
bending step including exerting a mechanical force intermediate the
pair of gripped locations and the third location that opposes the
removal of the bag from the bag magazine during the initial removal
of the bag from the bag magazine.
39. The method of claim 38 further characterized in shifting the
gripped side wall in a direction that the location of the
application of the mechanical force to the gripped side wall is
applied more remote to the bag mouth as the bag is initially
removed from the bag magazine.
40. In the method of transferring a flat folded tubular bag having
a first side wall, a second side wall and a bag mouth from a bag
magazine to a hopper assembly, comprising grippingly engaging the
first side wall at a first portion remote from the bag mouth, then
grippingly engaging the first side wall at a second portion
adjacent the bag mouth and applying a bag removal force at the
gripped portions to remove the gripped bag from the bag magazine
initially oppositing the removal force to the first bag side wall
intermediate the first and second portions to partially open the
bag mouth as the bag is being removed from the magazine.
41. The method of claim 40 further characterized in that the steps
of applying the removal force and opposing the withdrawing force
includes bending the first portion relative to the second portion
to move the part of the first portion most closely adjacent the bag
mouth away from the corresponding adjacent portion of the second
bag side wall.
42. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a longitudinal elongated frame, a plurality of
vacuum cups including a first vacuum cup and a second vacuum cup,
first means applying a vacuum to said cups and alternately
discontinuing the application of vacuum to the cups, second means
for abutting against the bag side wall intermediate the bag mouth
and the opposite end thereof, third means for mounting the vacuum
cups and second means to be engageable with said side wall and
moving the vacuum cups to act in cooperation with the second means
to at least partially open the bag mouth as the cups and second
means are moved away from the magazine, fourth means for mounting
the third means and moving the third means between a first position
that the vacuum cups and second means are substantially spaced from
the bags on the bag magazine, a second position that the vacuum
cups engage the side wall of a bag in a flat folded condition on
the magazine, and a third position that the bag gripped by the
vacuum cups in at least a partially opened condition has the hopper
jaws extended into the bag mouth, and fifth means for controlling
the application of vacuum by the first means to apply the vacuum to
the cups prior to the cups being moved to the second position and
discontinue the application of vacuum after the cups have been
moved from the second position to the third position, the fourth
means including a piston cylinder combination having a two way
piston cylinder combination, said combination having a cylinder and
a piston rod movable relative the cylinder between an extended
position to move the third means to said second position and a
retracted position to move the third means to a fourth position
that when the cups grip a bag the bag is spaced from both the
hopper jaws and the bag magazine, the third means including a
support member fixedly mounted on the piston rod, a transverse
shaft fixedly mounted by the support member, a first elongated
resilient mounting member having one end portion mounting the first
cup, a second elongated resilient mounting member having one end
portion mounting the second cup, said mounting members having
opposite end portions, sixth means for pivotally mounting the
opposite end portions on the shaft in transverse spaced
relationship and pivoting said mounting members in one angular
direction to move the first and second cups relative the support
member toward the bag magazine as the piston rod moves toward and
closely adjacent the third means second position, means for
resiliently urging the sixth means in the opposite angular
direction to a limit position, and seventh means for moving the
mounting members to position the first and second cups generally
transversely more closely adjacent one another as the third means
is moved toward and adjacent its second position and permitting the
mounting members moving the first and second cups transversely away
from one another as the third means is moved away from its second
position.
43. The apparatus of claim 42 further characterized in that the
mounting members comprise leaf springs having width dimensions in
planes generally perpendicular to the axis of pivotal movement of
the members relative the shaft and that the seventh means includes
bearing members having one end portions fixedly mounted on the
shaft.
44. In bag pick up mechanism, a support member, a transverse shaft
fixedly moved by the support member, a first, a second and a third
vacuum cup having a rim portion, first means for pivotally mounting
the first and second cups on the shaft in transverse spaced
relationship generally on one side of the shaft, a transversely
elongated break member having an axis of elongation, second means
for mounting the break member parallel to the shaft, resiliently
retaining the break member in a datum position, and permitting the
break member being pivoted in one angular direction relative the
shaft, third means for pivotally mounting the third cup on the
support member on generally the opposite side of the shaft from the
first and second cups, fourth means for resiliently retaining the
first and third means in limit positions that the first and second
cup rim portions are on one side of a plane of the axis of the
break member and passing through the third cup rim portions and
permitting movement of the first and third means to a bag pick up
position that the rim portions and break member are in a common
plane.
45. The apparatus of claim 44 further characterized in that the
first means includes a pair of elongated, transversely spaced leaf
springs each having one end portion mounting the first vacuum cup
and second vacuum cup respectively, resiliently retaining the first
and second cups in a preselected transverse spaced relationship and
permitting the first and second cups being moved transversely more
closely adjacent one another, and that there is provided means
mounted on the shaft to move the leaf springs to position said cups
transversely more closely adjacent one another as first and third
means are moved from their limit positions to their bag pick up
positions.
46. The apparatus of claim 1 further characterized in that said
plurality of vacuum cups includes a third vacuum cup and that said
fifth means includes means for mounting the third cup for
engagement with said side wall between the bag mouth and second
means and in spaced relationship to the first cup.
47. The apparatus of claim 1 further characterized in that said
second means includes a transversely elongated break member having
an axis of elongation, that the first and second cups each have a
rim portion and that the fifth means includes means for resiliently
retaining the first and second cups and break member in a datum
limit position that the first cup rim portion is on one side of a
plane of the axis of the break member and passing through the
second cup rim portion and permitting movement of the first and
second cups and break member to a bag pick up position that the rim
portions and break member are in a common plane.
48. For grippingly engaging a side wall of a bag in a flat folded
condition on a bag magazine, transferring the gripped bag to a
hopper spout assembly having openable jaws and at least partially
opening bag mouth portions sufficiently during the transfer
operation to have the hopper jaws in a closed condition extendable
into the at least partially opened bag mouth, bag transferring
apparatus comprising a longitudinal elongated frame, a plurality of
vacuum cups, said plurality of vacuum cups including a first and
second cup, first means for applying a vacuum to said cups and
alternately discontinuing the application of vacuum to the cups,
second means for abutting against the bag side wall intermediate
the bag mouth and the opposite end thereof, third means for
mounting the vacuum cups and second means to be engageable with
said side wall and moving the vacuum cups to act in cooperation
with the second means to at least partially open the bag mouth as
the cups and second means are moved away from the magazine, fourth
means for mounting the third means and moving the third means
between a first position that the vacuum cups and second means are
substantially spaced from the bags on the bag magazine, a second
position that the vacuum cups engage the side wall of a bag in a
flat folded condition on the magazine, and a third position that
the bag gripped by the vacuum cups in at least a partially opened
condition has the hopper jaws extended into the bag mouth, and
fifth means for controlling the application of vacuum by the first
means to apply the vacuum to the cups prior to the cups being moved
to the second position and discontinue the application of vacuum
after the cups have been moved from the second position to the
third position, said third means including a pair of elongated,
transversely spaced leaf springs each having one end portion
mounting the first and second cups respectively, resiliently
retaining the first and second cups in a preselected transverse
spaced relationship and permitting the first and second cups being
moved transversely more closely adjacent one another, said leaf
springs mounting the first and second cups for engagement with said
side wall intermediate the second means and the bag mouth, and
means to move the leaf springs to position said cups transversely
more closely adjacent one another as the cups are moved from said
first position to said second position.
49. For conveying a plurality of spaced stacks of flat folded bags
to a position to be transferred to a hopper assembly and
transferring bags to the hopper assembly, a bag magazine comprising
a transversely elongated frame having first and second end
portions, a drive roll mounted on the frame one portion and a
driven roll mounted at the frame other end portion, said rolls
being mounted by the frame generally parallel to one another and at
a substantial inclined angle to the horizontal, an endless conveyor
belt mounted by said rolls that has an upper run, a platform
mounted by the frame to support said upper run intermediate the
rolls, said upper run having a lower edge, a transversely elongated
bottom wall mounted along the lower edge in a fixed position by at
least one of the platform and frame, an end wall member mounted at
least in part by at least one of the frame, bottom wall and the
platform, said end wall member having a vertical wall portion in
overhanging relationship to the upper run to extend generally
perpendicular to the bottom wall and the upper run to limit
movement of the stacks of bags in one direction, means to drive
said drive roll to move the upper run in said one direction and
first means to selectively actuate the drive means and deactuate
the drive means and bag transfer apparatus having a second frame
mounting the hopper assembly at a higher elevation than the bag
magazine, operable bag pickup mechanism for grippingly engaging
only one side wall of a bag on the magazine and at least partially
opening the bag mouth as the bag is removed from the magazine, a
two way acting piston cylinder combination having an elongated
cylinder and a piston rod mounting said bag pick up mechanism and
moving the bag pick up mechanism between an extended first position
relative the cylinder and a retracted second position relative the
cylinder and operable second means mounting cylinder and moving the
cylinder between a third position that the cylinder extends
generally perpendicular to the upper run and at a location that the
bag pick up mechanism in the first position abuts against a bag on
the stack of bags adjacent the end wall vertical portion and a
fourth position that the bag pick up mechanism in the first
position transfers the picked up bag to the hopper assembly, and
control means for operating the bag pick up mechanism to its first
position with the cylinder in its third position to grippingly
engage the bag side wall.
Description
BACKGROUND OF THE INVENTION
A bag hanger assembly having vacuum cups to grip a flat folded bag
and transfer the bag from a bag magazine to a hopper assembly.
In the prior art it is old to use vacuum cups to first grip one
side wall of a bag to remove it from a bag magazine and then grip
the opposite bag side wall to at least partially open the bag and
transfer the partially opened bag, for example see U.S. Pat. No.
3,050,918; and it is old to use a combination of vacuum cups and
blowing air under pressure to partially open a bag. However such
prior art apparatus is quite complex and expensive; and in the case
of larger size bags, for example 50 to 100 pound size bags, the use
of a jet of air to open a bag relatively frequently does not result
in the bag being at least partially opened. In order to overcome
problems such as the above, as well as others, this invention has
been made.
SUMMARY OF THE INVENTION
Bag hanger apparatus having a plurality of vacuum cups and a break
member to abut one side wall of a bag and at least partially open
the bag mouth as the bag is retracted from the bag magazine, vacuum
cup and break member mounting mechanism to move the cups and break
member relative one another to partially open the bag mouth as the
bag is moved away from the magazine, and a power assembly for
moving the mounting mechanism between a retracted first position,
an extended second position and a third position remote from the
magazine where the bag is transferred onto a hopper spout assembly
to be supported thereby for dumping a charge into the bag.
One of the objects of this invention is to provide new and novel
bag pick up mechanism for grippingly engaging a bag and at least
partially opening the bag mouth as the bag is moved away from the
bag magazine. In furtherance of the above mentioned object, it is a
further object to provide new and novel mechanism that at least
partially opens a bag mouth while grippingly engaging only one bag
side wall.
Another object of this invention is to provide new and novel
apparatus for grippingly engaging the side wall of a bag on a bag
magazine adjacent the bag mouth and moving one gripped side wall
portion relative the other gripped side wall portion to partially
open the bag while removing the bag from the magazine. A further
object of this invention is to provide a new and novel bag magazine
to convey a plurality of stacks of bags in inclined conditions
successively to a given location to be picked up by bag pick up
mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the apparatus of this invention showing
the hopper assembly in a position for receiving a bag and the bag
pick up assembly in a position that the bag pick up mechanism is in
a retracted condition adjacent the bag magazine;
FIG. 2 is a fragmentary enlarged view of a portion of the structure
of FIG. 1, said view showing the hopper assembly in solid lines, in
a bag clamped, bag filling position, and the bag pick up mechanism
in solid lines in a rotated, retracted position after it has moved
a bag onto the hopper assembly; said view also showing in dotted
lines portions of the hopper and pick up assemblies in positions
that the bag has just been moved onto the hopper spout in a closed
position;
FIG. 3 is a still further enlarged fragmentary view of the bag pick
up mechanism in a position that the lower vacuum cup thereof has
just been moved into engagement with a bag on the bag magazine and
showing the vacuum cups and break member in their datum positions
relative the block that mounts said cups and break member;
FIG. 4 is a view of the bag pick up mechanism generally taken along
the line and in the direction of the arrows 4--4 of FIG. 5 other
than no bag is shown;
FIG. 5 is a side view of the bag pick up mechanism in a position
that all the vacuum cups are engaging a bag on the magazine, said
view being generally taken along the line and in the direction of
the arrows 5--5 of FIG. 4;
FIG. 6 is a fragmentary view of a portion of the structure shown in
FIG. 3 to more clearly illustrate the mounting of the bottom vacuum
cup, said view being generally taken along the line and in the
direction of the arrows 6--6 of FIG. 4;
FIG. 7 is a front view of the bag magazine, said view being
generally taken along the line and in the direction of arrow 7--7
in FIG. 1;
FIG. 8 is a side view of the bag pick up mechanism in a position
just after it is initially started retracting a bag from the bag
magazine;
FIG. 9 is a fragmentary view of the structure of FIG. 8 to
demonstrate the general positions of the vacuum cups after the bag
gripped thereby had been moved completely out of engagement with
the bags of the bag magazine;
FIG. 10 is a diagrammatic view showing the mouth end of a bag that
is being held by the vacuum cups in the position of FIG. 9;
FIG. 11 is a schematic showing of the air control circuitry and
components of the apparatus of this invention;
FIG. 12 is a fragmentary side view of the bag pick up assembly
cylinder and guide rod in a retracted position and the mounting of
the limit vacuum switch that is operated thereby;
FIG. 13 is a diagrammatic showing of the mounting of a plurality of
limit vacuum switches and the cams for operating said switched;
and
FIG. 14 is a fragmentary showing of the bag jaw operating piston
cylinder combination and the limit vacuum switch operated
thereby.
Referring now in particular to FIG. 1 there is illustrated a bag
hanger assembly, generally designated at 10, for removing a bag
from the bag magazine, generally designated at 11, opening the bag,
and after the bag has been filled, depositing the filled bag on the
V-trough conveyor, generally designated 12. As the conveyor 12 is
of a conventional construction, it will not be described.
The bag hanger assembly includes a frame, generally designated 15,
having a pair of transversely spaced, vertical, front uprights 17;
a pair of rear uprights 16; a pair of longitudinal, tranversely
spaced longitudinal channels 18, each channel 18 being connected to
the top ends of uprights 16 and 17 to extend forwardly of the
uprights 16 in over-hanging relationship to the V-trough conveyor;
vertically spaced, longitudinally elongated lower channels 19 that
extend between and have opposite ends joined to adjacent uprights
16 and 17; and transverse channels 20 extending between and joined
to uprights 18.
A bag pick up assembly, generally designated 22, includes a
transverse shaft 23 that extends between and has its opposite ends
pivotally mounted by the intermediate portions of channels 19 to be
in overhanging relationship to one end portion of the magazine 11.
To pivot the shaft 23 about its axis, one end of an arm 24 is
clamped to the shaft while the opposite end is pivotally connected
at 25 to the piston rod 26 of a piston cylinder combination that
includes a cylinder 27. The end of the cylinder remote from pivot
26 is pivotally connected at 28 to a bracket that in turn is
mounted on the rear transverse channel 20.
An elongated bracket 32 has one end portion secured to intermediate
portion of shaft 23 to rotate therewith. The cylinder 33 of a
piston cylinder combination 33, 34 is fixedly attached to bracket
32 to extend parallel to said bracket; the aforementioned
combination also including a piston rod 34 that mounts a block 35
to move therewith. One end of a guide rod 36 is fixedly attached to
block 35 so that the guide rod extends away from the block in the
same direction as the piston rod, the guide rod being slidably
extended through spaced guides 37 that in turn are mounted on a
bracket 38 that is attached to bracket 32 (see FIGS. 3 and 4).
The bag pick up mechanism , generally designated 42, includes a
transverse pivot shaft 43 that has its intermediate portion mounted
by block 35 in a fixed angular position relative the block (see
FIGS. 4 and 5). On each transverse side of the block there is
pivotally mounted a top vacuum cup pick up assembly, generally
designated 44. Since each assembly 44 is the same construction
other than they are asymmetrically mounted on the shaft, primarily
only one assembly 44 will be described. Each assembly 44 includes a
bag 46 that has one end fixedly clamped to the shaft 43, an
elongated bracket 47 having one end portion transversely spaced
from the bar 46 and clamped to the shaft in a fixed axial position
and a control arm 48 having a boss portion that is pivotally
mounted on the shaft intermediate the bar and bracket. A transverse
pin 49 is mounted by bar 46 to extend into the path of movement of
the control arm to limit the pivotal movement of the arm in one
direction (opposite arrow 256). Further, a coil spring 50 has one
end mounted by the other end of a bar 46 and has an opposite end
mounted by the intermediate portion of a bar 51 to resiliently urge
bar 48 to move in a direction opposite arrow 256 to a position to
abut against pin 49; bar 51 being welded to the control arm
adjacent shaft 43 to extend at right angles to the control arm. The
outer end of the control arm 48 mounts a transverse shaft 52 which
in turn mounts a roller 53 to rotate about an axis parallel to
shaft 43.
Fixedly attached to the arm 51 is an elongated leaf spring 56 that
extends generally parallel to the control arm in a direction
opposite that which the major portion of the control arm extends
away from arm 51. The opposite end of the leaf spring mount a
member 57 which in turn mounts the shaft 58a of a top vacuum cup 58
in a fixed position relative said opposite end portion. Mounted on
shaft portion 58a is the resilient cup portion 58b having a
circular rim to form a fluid seal with a bag; portions 58a, 58b
having an internal vacuum channel 59 in fluid communication with a
line 173.
The thickness direction of the springs 56 are transverse whereby
the top vacuum cups may be relatively easily moved in a transverse
direction; however are relatively rigidly mounted in a direction
perpendicular to the direction of elongation of arm 51 and the
transverse direction. A transverse bag 61 has one end mounted on
the radial outer end of bracket 47 and an opposite end that mounts
a bearing 62 in a position to force the adjacent leaf spring to
move the vacuum cup 58 mounted on said leaf spring a short distance
transversely toward the other vacuum cup 58. That is, as arm 51 is
moved in the direction of arrow 256 from the limit position
abutting against pin 49, the intermediate portion leaf spring 56
moves into abutting engagement with the adjacent bearing 62 to
force the leaf spring to move its vacuum cup in the aforementioned
manner.
Referring to FIGS. 4 and 6, the bottom vacuum cup pick up assembly,
generally designated 64, includes a pair of bars 65 that have one
ends pivotally connected at 66 to the guide rod 36 to pivot about
an axis parallel to the axis of elongation of shaft 43; pivot
member 66 being located adjacent to block 35. The opposite ends of
the bars 65 mount a pivot member 67 which in turn mounts a first
tab that is fixedly secured to the shaft portion 68a of the rear
(bottom) vacuum cup 68; shaft 68a being located closely adjacent
pivot 67 and intermediate pivot 66 and 67. Secured to the shaft 68a
diametrically opposite the first tab is a second tab 70, a coil
spring 71 having one end attached to tab 70 and an opposite end
attached to a bracket 72 that is secured to block 35. A bar 73 is
mounted by bars 65, the bar 73 mounting an adjustment screw 74 in a
position to abut against block 35 to limit the pivotal movement of
bar 65 about pivot 66 in a direction of arrow 76. The coil spring
71 through members 67 and 70 resiliently urge bars 65 to pivot
about pivot member 66 in the direction of the arrow 76; and
additionally resiliently urge the bottom vacuum cup to a position
that the coil spring 70 lies in a straight line between pivot 67
and the connection of the spring to bracket 72.
The bottom vacuum cup also includes a resilient cup portion 68b
that is mounted on the shaft portion 68a, the vacuum cup having an
internal channel (not shown) for applying vacuum to the cup
portion.
A break bar assembly, generally designated 79 includes a collar 80
on each end of the shaft 43 that is retained in place on the shaft
by a set screw, a bracket 82 having one end portion pivotally
mounted on the respective end portion of the shaft and a torsion
spring 81 that is coiled about the shaft. Each torsion spring has
one end secured in an appropriate aperture in the adjacent collar
80 and an opposite end extending into an aperture in the bracket
82. Thus the torsion springs resiliently urge the brackets 82 to
extend outwardly from the shaft 43 at a given angle. The end
portions of the brackets mounted on shaft 43 are generally at right
angles to the opposite end portions of said brackets, the opposite
end portions of the brackets being attached to the break rod 83 to
mount the break rod to extend parallel to the shaft 43. The shaft
43 through the above described structure is resiliently retained in
a position on the opposite side of the block 35 from the cylinder
33 and generally intermediate the top vacuum cups and shaft 43 such
as shown in FIG. 2.
Referring now to FIGS. 1 and 2, the hopper assembly, generally
designated 90 is mounted by a pair of transverse frame members 91,
92 longitudinally forward of uprights 16 and in a position to
receive a bag from the bag pick up assembly. The hopper assembly
includes a hopper body 93 that has a fixed jaw 94 joined to the
body to depend therefrom. The fixed jaw has side wall portions 94b
that are of a generally triangular shape and a web portion 94a.
Dependently secured to frame members 91, 92 on either side of the
hopper and spaced therefrom are longitudinal plates 95. The plates
95 pivotally mount transverse shafts 97, 98, one on either
longitudinal side of the hopper. The legs of a generally U-shaped
bracket 99 have their upper ends fixedly attached to the shaft 97
and their lower ends joined to a web portion 99b that mounts to a
bag clamp 100 in position to clamp one side wall of a bag against
the lower end portion of the web 94a.
In order to move the bag clamp 100 between the solid line bag
clamping position of FIG. 2 and dotted line open position, a
bracket 101 is fixedly attached to web portion 99b and pivotally
connected at 102 to the piston rod 103 of a piston cylinder
combination 103, 104. The cylinder 104 of the aforementioned
combination is pivotally connected at 105 to a bracket 106 that is
mounted by a channel 20.
Pivotally connected at 110 to tabs joined to the legs of bracket 99
are the one ends of the links 111, the opposite ends of the links
being pivotally connected at 112 to the lower ends of bars 113. The
upper ends of the bars are fixedly attached to shaft 98 to pivot
said shaft at the same time the bracket 99 is pivoted. The bars 113
are secured to the side walls 115a of the movable hopper jaw 115;
the upper end of the spout jaw 115 being adjacent shaft 98. As
indicated in FIG. 2, the web portion 115b of jaw 115 extends to a
lower elevation than side walls 115a of jaw 115.
The upper ends of the legs of the generally U-shaped bracket 116
are dependingly welded to plates 95; the web portion of the bracket
mounting a bag clamp 117 in a position to be abuttable against the
web portion 115b of jaw 115. At the time bag clamp 100 is moved to
clamp a bag side wall against jaw 94, the web portion of jaw 115 is
moved to clamp the opposite bag side wall against bag clamp 117.
Preferably the bag clamps have resilient pads abuttable against the
jaw web portions.
The bag magazine 11 includes a frame having a pair of transversely
elongated, longitudinally spaced channels 119, 120 with the channel
120 being mounted at a substantially higher elevation than channel
119 (see FIGS. 1 and 7). The one end of the channels mount in drive
roller 121 to be at a substantial angle relative the horizontal
such as indicated in FIG. 1, the drive roller being driven through
a chain 123 extended over a sprocket keyed to roller 121 and a
sprocket keyed to the reducer shaft of the motor-reducer
combination 124. The opposite ends of channels 119, 120 mount a
driven roller 125 that is parallel to roller 121 and inclines at
the same angle.
A pair of spaced conveyor belts 126, 127 are extended around
rollers 121, 125 with the upper runs of the belts slidably
extending over the top surface of the platform 128 that is mounted
by the channels 119, 120 intermediate rollers 121, 125. The lower
runs of belts 126, 127 are extended over tensioning idler rollers
129 that are mounted by the aforementioned channels.
A plurality of frame members 130 are secured to channel 19 to
extend perpendicular to the top surfaces of the upper runs of belts
126, 127; a bottom wall 131 being mounted by frame members 130 to
have a smooth surface adjacent the lower edge of the upper run of
the lower belt 127.
An end wall 133 is in part mounted by platform 128 and in part by
the bottom wall 131 to have a vertical surface portion 133a between
rollers 121, 125 and more closely adjacent roller 121 than roller
125. Surface portion 133a is located such that when a stack of flat
folded tubular bags 134 abuts thereagainst, stack 134 is aligned
with the bag pick up assembly to have the uppermost bag removed by
said assembly. The end wall also includes a top surface portion
133b on which there is mounted a motor stop limit switch and a no
bag control limit switch 136, 137, respectively. Switches 136, 137
respectively have operating spring arms 138, 139 that extend
downwardly into platform slots 128a to be forced closely adjacent
surface portion 133a by bag stack 134 being moved against wall
portion 133a.
The upper runs of the conveyor belts 126, 127 that move over
platform 128 are of a sufficient length to have a number of spaced
stacks of bags positioned thereon. Further the belts 126, 127 are
inclined at an angle that bottoms (closed ends) the bags in each
stack slidingly bear against the adjacent surface of bottom wall
131.
Referring now to FIG. 11, the control circuitry, generally
designated 150, includes a main air line 151 having a plurality of
junctions 152-158 thereon. Junction 152 is connected to a source of
pressurized air 160 by an on-off switch 159; and to a first port
161 of an air operated valve 163. Valve 163 also includes a port
162 that is fluidly connected to the control port of the vacuum
control valve 164. Further valve 163 includes a port 165, a port
166 and a valve member 167. When air under pressure is applied to
port 165, valve member 167 either remains in, or moves to a
position to permit air flow between ports 161, 162; while, when air
under pressure is applied to port 166, the valve member 167 moves
to a position blocking air flow through ports 161, 162. The valve
member 167 remains in one position until air under pressure has
been applied to the respective one of ports 165, 166 to move the
valve member to its other position.
Vacuum control valve 164 is provided in line 171 intermediate the
vacuum source 170 and junction 172. When air under pressure is
applied to control port of valve 164, the vacuum source is in fluid
communication with junction 172 while when no pressure is applied
to the control port, junction 172 is no longer fluidly connected to
the vacuum source. Lines 173 fluidly connect the junction 172 to
the fluid passageways in the vacuum cups. Connected in series
between junctions 172 and 176 are a check valve 174 and a switch
177. The check valve is of a construction that when the vacuum has
dropped to a preselected negative pressure, then the vacuum is
applied at switch 177. When switch 177 is in a closed position, the
check valve is in fluid communication with junction 176, and when
in an open position, the application of vacuum through switch 177
is blocked.
A limit vacuum switch 180 is fluidly connected across junction 153
and a first inlet port 181 of a valve 184, a restrictor 185 being
fluidly connected across junction 186 and a second inlet port 183
of said valve 184. The valve 184 has an outlet port 182 connected
by an air line to junction 176. Valve 184 is of a construction that
has a ball to block port 183 when air under pressure is applied at
port 181, block port 181 when air under pressure is applied at port
183, and to permit free flow of air from the unblocked inlet port
to the outlet port.
A limit valve switch 189 is connected across junctions 154, 190,
junction 190 being fluidly connected to port 166 of valve 163 and
to the inlet port 191 of valve 192. A manually operated on-off
switch 195 is fluidly connected across junction 155 and a second
inlet port 194 of valve 192, valve 192 having an an outlet port
193. Valve 192 is of the same construction as valve 184.
A valve 197 has a valve member 198 that is movable between two
positions and remains in one of said positions until air under
pressure is applied to the appropriate end to move the valve member
to its second position. Valve 197 includes a port 196 fluidly
connected to junction 176 such that when air under pressure is
applied at port 196, the valve member is moved for applying air
under pressure to port 33b of cylinder 33 and exhaust air under
pressure from port 33a; while when air under pressure is applied to
port 199 of valve 197, the valve member 198 is moved to apply air
under pressure to port 33a and exhaust air from port 33b. Port 199
is fluidly connected to port 193 of valve 192.
A valve 205 that is of the same construction as valve 197 has a
valve member 208, a port 207 at one end that is connected to
junction 190, and a port 206 at the opposite end that is connected
to the output port 272 of a valve 209 that is of the same
construction as valve 184. When air under pressure is applied at
port 207, valve member 208 moves to apply air under pressure to
port 27a of cylinder 27 and exhaust air from port 27b; while when
air under pressure has been applied to port 206, the valve member
208 moves to position that air under pressure is applied at port
27b. A switch 211 that is resiliently retained in an open position
is fluidly connected across junction 156 and a first inlet port 271
of valve 209 to upon the switch 211 being manually depressed,
fluidly connect said junction to said port. Connected in series
across junction 212 and the second inlet port 270 of valve 209 are
a pair of limit valve switches 213, 214; junction 212 being fluidly
connected to junction 186. A limit valve switch 137 is connected
across junctions 212, 216 while a limit valve switch 217 is
connected across junctions 157, 216.
A limit valve switch 215 is connected across junction 158 and a
port 219 that is at one end of valve 220, valve 220 being of the
same construction as valve 197. Valve 220 has a second port at the
opposite end connected to junction 216 and a valve member 221 that
when air under pressure has been applied to port 222, the valve
member is moved to a position that air under pressure is applied to
port 104b of cylinder 104 and exhausted from port 104a whereby the
piston rod 103 is moved to a retracted position. When air under
pressure is applied at port 219, valve member 221 moves to its
opposite position for exhausting air from port 104b and applying
air under pressure at port 104a to extend the piston rod.
A limit valve switch 225 is connected between junction 158 and the
control port of a valve 226, the valve 226 having a valve member
(not shown) that is spring urged to a closed position, but that
when air under pressure is applied to the control port, applies air
under pressure to the lines 173 of the vacuum cups for purposes to
be set forth hereinafter.
To be mentioned is that each of valves 197, 205 and 220 are
connected across air lines (under pressure) that are utilized to
supply air under pressure to the respective end of cylinders 33, 27
and 104, arrows pointing toward the respective valves indicating
the pressurized air line and the arrow pointing away from the
respective valve indicating the exhaust line. Further each of
switches 180, 189, 195, 211, 217, 215 and 225 is of a type that
when in an open condition, air from the line 151 cannot escape
through the switch, but air can escape from the lines connected to
the switches on the side opposite that to which line 151 is
connected. When a vacuum is applied at port 182 from valve 174, the
ball of valve 184 moves to block port 182. When no air under
pressure is applied to the inlet ports of valve 209, both switches
211 and 214 exhaust air from port 272 to the atmosphere, provided
switches 211, 214 are not in a closed position.
Referring to FIG. 13, a transverse channel 230 has its opposite
ends mounted by frame members 19 at a location adjacent shaft 23.
The limit switch valve 215, 217, 225, 180 and 177 are mounted on
the channel in transverse spaced relationship to have their
actuator members in a position to be operated by the cam members
234 to 238 respectively that are retained on shaft 23 in selected
angular position by set screws (not shown). The shape of the cam
members are such to accomplish the actuation of the valves in the
manner to be described hereinafter. Valve member 214 is mounted on
channel 230 in a position to have its actuator operated by the
guide rod 36 to close said valve when both the guide rod is in a
retracted position and the piston cylinder combination 26, 27 is in
an extended position. A limit vacuum switch 189 is mounted by a
block 240 that in turn is mounted by the cylinder 104 to move
therewith. Block 240 mounts switch 189 in a position that its
actuator will be operated by the operator 241 on the piston rod 103
as the piston rod moves to its extended position.
Limit switch 213 is mounted on a V-trough conveyor in a position
transversely spaced from a bag that is being moved from the
magazine to the hopper, and a filled bag dropping onto the
conveyor; however, in a position to have its spring actuator arm
213a operate the switch to a closed position after the V-trough
conveyor has moved the bag a short distance from the location that
the bag is deposited on the conveyor by being dropped from the
hopper.
For purposes of describing the operation of the apparatus of this
invention, it will be assumed that a stack of bags 132 are on the
magazine abutting against wall portion 133a and accordingly the
actuator 139 retains switch 137 in a closed position. Further, it
is assumed that the piston rods 26 and 34 are in extended positions
and that piston rod 103 is in a retracted position. As a result the
vacuum cups abut against the top bag on stack 134. At this time
limit switches 217 and 177 are in closed positions (due to the
angular position of shaft 23) and limit switch 214 is in an open
condition due to the guide rod being remote from said switch.
Further, switch 189 is in an open condition.
Now, as soon as switch 159 is moved to closed position, air under
pressure is applied through port 222 of valve 220 whereby valve
member 221 is retained in a position that piston cylinder
combination 103, 104 remains in (or moves to) its retracted
position. Since limit switches 217, 137 are in a closed position,
air under pressure is applied at junction 186 to pass through
restrictor 185 and subsequently to port 196 of valve 197 whereby
valve member 198 remains in (or moves to) a position that cylinder
33 is extended. Also the application of air under pressure at
junction 186 is applied through port 165 whereby the valve member
167 remains in (or moves to) a position that air under pressure is
applied to the control port of the vacuum control valve 164. This
results in a vacuum being applied from the vacuum source to
junction 172 and thereby to the vacuum cups. Further, the vacuum
applied at junction 172 is applied at check valve 174. Since the
cups abut against the uppermost bag, insufficient air is drawn into
the cups to prevent a rapid decrease of pressure at junction 172.
The increasing negative pressure builds up until it is below the
selected point for check valve 174 and thereupon the check valve
permits the vacuum to be applied from junction 172 to and through
limit switch 177 and thence to junction 176. The pull of the vacuum
at junction 176 is sufficiently greater than that of the
application of air under pressure from port 182 to junction 176
that valve member 198 is drawn by the vacuum toward port 196
whereby air under pressure is applied at port 33a to retract the
bag pick up mechanism. Upon the bag pick up mechanism being moved
to its retracted position, the guide rod operates limit valve
switch 214 to a closed position.
Assuming that in the initial retraction of the vacuum cups one of
the cups did not form a vacuum grip with the bag, then air would
flow through the cup and the respective line 173 to junction 172
whereby the negative pressure at junction 172 would decrease, and
as a result check valve 174 is resiliently urged to a closed
position. The closing of check valve 174 results in the application
of air under pressure through restrictor 185 gradually building up
at port 196 sufficiently to move the valve member 198 to adjacent
port 199. Accordingly, air under pressure is applied to cylinder 33
at port 33b to move its piston rod 34 to an extended position.
Thus, the vacuum cups are again moved to the lower position to abut
against the bag to permit air being drawn in through the vacuum
cup, and thereafter the vacuum cups are retracted in a manner
described in the preceding paragraph. If the cups again fail to
properly vacuum grip the bag, the cycle of extension and retraction
of piston-cylinder combination 33, 34 is repeated until an operator
stops the reciprocating action of the cups, or until all cups form
a sealing engagement with the bag.
Assuming that the bag was properly gripped by all cups, nothing
further will happen during the first cycle of operation of the day
until either switch 213 is manually operated to a closed position;
or switch 211 is manually depressed. Normally switch 211 would be
manually depressed, this resulting in air under pressure being
applied to port 206 of valve member 205 to move it away from port
206 whereby air under pressure is applied to port 27b to retract
piston rod 26. This rotates cylinder 33 and shaft 23 about the axis
of shaft 23 in the direction of arrow 450. The first few degrees of
rotation of shaft 23 results in vacuum limit switch 217 moving to
an open position and shortly thereafter limit valve switch 177 to
an open condition.
After the bag gripped on the bag pick up mechanism has been
angularly moved sufficiently about the axis of shaft 23 so that the
bag will clear the bags on the bag magazine, limit switch 180 is
operated to a closed position to apply air under pressure at inlet
181 and thereby through junction 176 to port 196 to operate the
valve member 198 to its position adjacent port 199. As a result,
air under pressure is applied to piston cylinder combination 33, 34
to move the bag pick up mechanism to an extended position. It is to
be noted that limit switch 180 is only operated to a closed
position during the short increment of angular movement of the
shaft in the direction of the arrow 450, but is not operated to a
closed position when the shaft is rotated in the opposite
direction. Piston cylinder combination 33, 34 is in its fully
expanded condition prior to the time shaft 23 has been rotated
sufficiently to move said combination to a horizontal
condition.
Just prior to the time piston cylinder combination 33, 34 is moved
to horizontal condition, limit vacuum switch 214 is operated to a
closed condition to apply air under pressure to port 219 to valve
220. As a result, valve member 221 is moved to a position that air
under pressure is applied to piston cylinder combination 103, 104
to operate it to its extended condition. As combination 103, 104 is
being operated to its extended condition, one bag side wall is
moved between bag clamp 100 and jaw 94a while the opposite side
wall is moved between bag clamp 117 and jaw 115. The bag clamp 99b
in moving toward a position to abut against jaw 94 results in jaw
115 moving the other bag side wall to a more fully opened condition
and thence clamp it against bag clamp 117.
Just prior to the piston rod being moved to the fully extended
stroke of combination 103, 104, switch 189 is actuated to a closed
position and at the end of said extending stroke, switch 189 opens.
Switch 189 is of the type that is actuated to a closed position
only during the extension stroke of combination 103, 104, not
during the retraction stroke.
The duration of closure of switch 189 is sufficient that air under
pressure is applied to junction 190 and thence to port 166 to
operate valve member 167 to an open condition whereby the vacuum
control switch 164 disconnects the application of vacuum from the
vacuum source to junction 172. As a result, the vacuum cups release
their gripping engagement with the bag which is then fully
supported by the hopper assembly 90. Also, the application of air
under pressure at junction 190 results in valve member 208 being
operated to its position adjacent port 206 whereby air under
pressure is applied to piston cylinder combination 26, 27 to
initiate the extending movement thereof, port 27a having a
restrictor therein to act as a time delay whereby a second bag is
not moved to the hopper assembly until the bag thereon has been
filled, deposited on conveyor 12 and moved thereby out of the path
of movement of the second bag. Further, the application of air
under pressure at junction 190 results in air under pressure being
applied at port 199 of valve 197 to operate the valve for applying
air under pressure to piston cylinder combination 33, 34 to move
the piston rod 34 toward its retracted position.
The hopper assembly is provided with conventional switches (not
shown) that actuate the scale dump mechanism thereof to dump a
charge, provided both bag side walls are properly clamped on the
hopper assembly.
The initial movement of combination 26, 27 toward its extended
condition in rotating shaft 23 a few degrees in the direction
opposite arrow 450 results in switch 215 resiliently returning to
an open condition. Also, the initial movement of shaft 23 in the
direction opposite arrow 450 momentarily actuates limit valve
switch 225 to a closed position (switch 225 not being operated to a
closed position when shaft 23 rotates in the direction of arrow
450) which in turn operates valve 226 to apply air under pressure
to lines 173 for purposes of blowing dust and other debris out of
the vacuum cups, switch 225 opening prior to the time that piston
cylinder combination 26, 27 is operated to its fully extended
condition. After switch 225 opens, and prior to piston rod 26 being
moved to its fully extended position, limit valve switch 177 is
moved to a closed position; and upon piston rod 26 being moved to
the fully extended condition, limit switch 217 is operated to a
closed condition. The closing of switch 217 results in air under
pressure being applied at junctions 186, 216 whereby valve 220 is
operated to apply air under pressure to the port 104a of cylinder
104, air under pressure is applied to vacuum control valve 164 to
open said valve whereby vacuum is applied to junction 172; and air
under pressure is applied at junction 176. As a result of applying
air under pressure at junction 176 (there being no substantial
decrease of pressure at check valve 174 due to the cups being
spaced from the bags), valve member 198 moves so that air under
pressure is applied to port 33b whereby the vacuum cups are moved
to abut against the second bag in the stack on the magazine; and
thereafter the operation continues in the manner previously
described with the exception that switch 211 does not have to be
operated to a closed position. The aforementioned exception results
from the fact that at the time air under pressure is applied at
port 222 of valve 220, the piston cylinder combination 103, 104 is
operated to a retracted condition whereby the bag is dropped from
the hopper. The filled bag in dropping on the V-trough conveyor is
moved by the conveyor to abut against arm 213a and thereby actuate
switch 213 to form a closed circuit through switches 217, 137, 213,
214 to junction 209 to apply air under pressure to port 206. In
this connection there is a restrictor provided in cylinder 27 (port
27a) to delay the movement of the cylinder to its fully extended
position sufficiently that the bag pick up devices are moved to
pick up a bag and retracted (guide rod 36) to close switch 214 just
prior to the closing of switch 213. Thus, the operation of
automatic.
It is to be noted that once the last bag of stack 134 has been
removed from the magazine, switch 137 moves to an open position to
prevent the application of air under pressure to junction 212 until
the magazine has advanced a stack of bags (stack 135) to close the
switch. At the same time switch 137 opens, the removal of the last
bag also results in the sensor finger 138 of switch 136 actuating
motor 124 to drive the conveyor belts 126, 127 until the second
stack of bags 135 abut against wall portion 133a. The second stack
of bags 135, in being moved to abut against wall 133a operate
switches 136, 137 to respectively de-energize motor 124 and close
switch 137.
With the aforementioned controls, after switch 211 has been closed
upon the initial raising of the first bag from the magazine at the
start of the day's operation, the apparatus of this invention will
continue functioning automatically as long as bags are placed on
the magazine to be moved thereby to abut against wall 133a.
It might be mentioned that in the event that the bags on the
magazine are not properly aligned, or that the vacuum cups are not
functioning properly to pick up a bag, switch 195 is operated to an
on position to complete an air circuitry between junctions 155 and
junction 194. This operates valve 197 to a condition that piston
cylinder combination 34, 33 is moved to and retained in a retracted
condition (even if air under pressure is applied at junction 176;
i.e. due to the provision of restrictor 185) until switch 195 is
again moved to an open position.
The general operation of the apparatus of this invention having
been described, the operation of the bag pick up assembly will now
be described in greater detail. For purposes of describing the
operation of the bag pick up mechanism, it will be assumed that it
is in the position shown in FIG. 1. As the piston rod 34 is moved
in the direction of arrow 255, vacuum cup 68 initially makes
contact with the top bag 134a in the stack 134. At the time cup 68
initially makes contact, the various member of the bag pick up
assembly are in the relative positions such as illustrated in FIG.
3. As piston rod 34 and block 35 further advances in the direction
of arrow 255, vacuum cup 68 is prevented from being moved further
in the same direction and this results in arm 65 pivoting about
pivot member 66 in the direction opposite arrow 76. Thereafter,
rollers 53 abut up against bag 134a, and the further movement of
block 35 in the direction of arrow 255 results in vacuum cups 58
being pivoted about shaft 43 in the direction of the arrow 256,
this being against the resistance of springs 50. At the time the
cup portions 58a are brought into engagement with bag 134a, the
break rod 83 is also brought into engagement with said bag. Due to
the resiliency of the cups the block 35 is permitted to move
further in the direction of arrow 255, this resulting in the break
rod being pivoted about shaft 43 in the direction of arrow 257 to
tension torsion springs 81. The cups in contacting the bag blocks
the in flow of air into the cups and this, through the controls
previously described, results in piston rod 34 being retracted.
Just prior to the initial retraction, the rims of the vacuum cups
lie in approximately the same plane as the break rod, such as shown
in FIG. 5.
Once the cups form a vacuum gripping engagement with the bag, the
spacing of vacuum cups 68b from the vacuum cups 58a is
substantially fixed, i.e. other than for the resiliency of the cups
and for slight relative movement permitted by springs 56. During
the initial retraction of the cups, the spring 71 urges the bar 70
to pivot about pivot 67 in the direction of arrow 260 and thereby
arm 65 to pivot about pivot member 66 in the direction of arrow 76;
the torsion springs urge the break rod to pivot about shaft 43 in
the direction opposite arrow 257, and spring 50 urges the vacuum
cups 58 to pivot about shaft 43 in the direction opposite arrow
256. As a result the bag is moved slightly in the direction of
arrow 265 relative to block 35 (FIG. 8) and the portion of the
gripper bag side wall between vacuum cup 68 and the break rod is
retained in one plane while the portion between the break rod and
vacuum cups 58 are moved to extend at an angle to the first
mentioned bag side wall portion such as shown in FIG. 8 for the
initial retracting movement of piston rod 34. Since the opposite
side wall is not grippingly engaged, the second mentioned bag side
wall portion of the bag is pulled away from the second bag side
wall and is in a position such as shown in FIG. 9 after the bag has
been moved away from the magazine. As a result, the bag is
initially broken open in the area of its bag mouth (see FIG. 10).
In this connection it is to be noted that the vacuum cups
grippingly engage, for example, a 50 pound bag, about 2 inches from
the marginal edges that in part define the bag mouth. Thus, the bag
pick up mechanism moves the two portions of one side wall relative
the other, non-gripped, side wall to partially open the bag mouth
sufficiently to have the hopper jaws extend thereinto as the bag is
swung up to the hopper as previously described, the bag mouth being
partially opened during the retraction of the piston rod 34 in the
direction opposite arrow 255 at the time piston rod 26 is in an
extended condition.
To be mentioned is that as block 35 is initially moved from the bag
pick up position of FIG. 1 (direction opposite arrow 255), the leaf
spring is pivoting relative to shaft 43 in the direction opposite
arrow 256, the leaf springs move out of abutting engagement of
bearings 62 and thus the vacuum cups 58 are resiliently urged to
more transversely spaced positions. As a result, any wrinkles in
the gripped side wall portion of the bag between cups 58 are
removed. As an example, the vacuum cups 58 may move about
one-fourth inch further apart as the leaf springs are moved
relative the bearings from the bag pick up position of FIG. 5 to
their limit position wherein bar 51 abuts against pin 49 (assuming
no bag is being gripped by the cups).
At the time the vacuum is released, the cups and the break rod
return to their datum positions relative block 35, the datum
positions relative the block 35 being shown in FIGS. 1 and 3. That
is, spring 50 pivots cups 58 in the direction opposite arrow 256
until rod 49 abuts against arm 51; spring 71 pivots bars 65 about
pivot member 66 in the direction of arrow 76 until stop 74 abuts
against block 35 and vacuum cup 68 pivots about pivot 67 in the
direction opposite arrow 260 until the spring 71 extends in a
straight line between pivot 67 and the connection of the spring to
bracket 72; and the break rod 83 is pivoted about the shaft 43 in
the direction opposite arrow 257 to relieve the tension in the
torsion springs.
Through the utilization of the break rod and the mounting of the
vacuum cups, the bag mouth is broken open by only grippingly
engaging one side wall 134a of the bag, and without the use of
separate mechanism, for example, air injection or vacuum cups to
grippingly engage the other side wall. Further, with the apparatus
of this invention the bags are not stacked on end, but are inclined
at an angle that helps in retaining them on the line with the
other, for example at an angle of 20.degree.-30.degree. relative
the horizontal.
To be mentioned is that the top vacuum cups are the ones that grip
the bag closely adjacent the bag mouth while the bottom cup is the
one that grips the bag more remote from he bag mouth than the top
cups. Thus with reference to the cups "top" and "bottom" is not
necessarily meant to refer to the relative elevations of the
cups.
Also, it is believed apparent that paper bags are stacked on the
magazine in a flat folded condition with the bag mouths at a higher
elevation than the opposite ends of the bags; the stacks are spaced
a few inches apart to permit proper operation of switches 136, 137
and the bags on one stack interferring with the removal of bags by
the bag pick up mechanism from the adjacent stack; and the magazine
supports the bags with the bag mouths more closely adjacent the
hopper assembly than the opposite ends of the bags. The apparatus
of this invention can be used for removing gusseted, pinch bottom
and relatively wide mouth non-gusseted paper bags from the
magazine, and partially opening such bags as they are removed by
the bag pick up mechanism from the magazine. In being used with
nongusseted paper bags, the vacuum cups have to be spaced a
substantial distance from the adjacent side edge of the bags in
flat folded conditions.
* * * * *