Note: Descriptions are shown in the official language in which they were submitted.
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MULTI-ACCESS STORAGE SYSTEM
SPECIFICATION
In order to meet a progressively increasing need
for the stoxage of hundreds, and in some instances,
thousands, of individual articles in a manner suitable
for retrieval of any of them by automatic means, there
has been an attempt to provide motorized storage racks.
The object of motorized racks has been to provide the
capability of delivering individual storage containers to
an unloading and loading station in response to a
computerized call system. Motorized racks of the kind
made reference to currently available are exemplified ~y
U.S. Patent No. 4,422,5S4.
Although such motorized racks have been a
notable advance in identifying and accelerating the
delivery of assorted parts from storage, some limitations
have been experienced, chief among which has been the
need for stopping the rack while a container is being
unloaded and continued holding of the rack in stopped
position for reloading. The time involved in a procedure
of this kind is appreciably exaggerated under
circumstances where unloading and loading has to take
place at the same location.
Another circumstance adding to the problem is
the need to have a constant record kept of the location
of containers reloaded on the motorized rack so that they
can again be identified accurately when needed. The
objectionable time delay becomes exaggerated to a
material degree when a multiple number of such motorized
racks are stacked one above the other in the interest of
taking full advantage of storage space available.
When it is borne in mind that on some occasions
containers can ~be relatively small for the storage of
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numerous inventory items of especially small dimensions, while
on other occasions large containers may be needed to store an
adequate number of relatively larger inventory items, the time
interval during which the motorized rack must be stopped for
unloading and loading can become critical.
Therefore, there is a need for a multi-access storage
system wherein the unloading of containers from the motorized
storage conveyor, and subsequent reloading, can take place
while the motorized rack continues traveling.
According to one aspect, the present invention
provides a multi-access storge system comprising: an endless
rack assembly including a plurality of vertical connected
racks each having a multiplicity of side-by-side load accommo-
dating stations, the racks being mounted for travel in a
horizontal plane about an endless loop that passes an extraction
site, the endless loop having a pair of elongated parallel
straight reaches and a pair of opposing end portions for forming
said straight reaches; conveyor attachment means at each of
said stations; a multiplicity of containers having complementary
container attachment means thereon for engagement with said
conveyor attachment means to releasably secure a particular
container individually to a particular station; an extraction
assembly adjacent said conveyor for extracting selected con-
tainers from the conveyor at said extraction site, said
extraction assembly including disengagement means for dis-
engaging the selected containers from the corresponding conveyor
attachment means at said extraction site, said disengagement
means including a diverting mechanism at said extraction site
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having a first operating position clear of said containers and
a second operating position wherein the diverting mechanism is
in potential engagement with said containers during travel of
said containers on said conveyor and wherein said diverting
mechanism is adapted, to effect disengagement of the selected
container from the conveyor while t:he conveyor remains in
continuous motion about the endless loop.
According to another aspect, the present invention
provides a multi-access storage system comprising: an endless
conveyor having a multiple number of load accommodating stations
mounted for travel in a horizontal plane about an endless loop,
the endless loop having a pair of elongated parallel straight
reaches and a pair of opposing end portions for forming said
straight reaches; conveyor attachment means at each of said
stations; a multiplicity of containers each having complemen-
tary container attachment means thereon for engaging said
conveyor attachment means to releasably secure individual
containers to said conveyor; an insertion assembly adjacent said
conveyor, the insertion assembly including insertion means
including an approach for directing said containers onto the
conveyor and having a first operating condition for inserting
containers onto said conveyor while said conveyor is in con-
tinuous motion about the endless loop, and guide means for
advancing a particular container to an insertion position
relative to a selected empty station passing the insertion site
and for moving the containers to a position wherein said con-
tainer attachment means engages the conveyor attachment means
of the selected empty station during travel of the corresponding
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station past the insertion site.
According to a further aspect, the present invention
provides a multi-access storage system comprising: an endless
conveyor rack assembly having a multiple number of load accom-
modating stations and mounted for travel in a horizontal plane
about an endless loop; container support means at each of said
stations; a multiplicity of containers having complementary
container support means thereon for engagement with said
conveyor support means to releasably mount containers indivi-
dually on said conveyor; an unloading assembly adjacent saidrack for unloading containers from the rack while said rack
remains in eontinuous motion about the endless loop, said un-
loading assembly including disengagement means for disengaging
the container support means of selected containers from their
corresponding conveyor support means, disposal means for
directing unloaded containers away from the rack, and elevating
means for selectively engaging the container to direct movement
of the container support means to a position free of said con-
veyor support means; and a loading assembly adjacent the rack
ineluding means for loading containers on the rack while said
rack remains in motion about the endless loop, said loading
assembly eomprising an approaeh for direeting partieular
eontainers onto the raek, and plaeement means for advaneing a
seleeted eontainer to a loading position relative to a seleeted
empty station and for moving the eontainer support means of the
seleeted eontainer to a position wherein said seleeted eontain-
er support means engages the eonveyor support means of the
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selected empty station.
IN THE DRAWINGS:
FIG. 1 is a plan view of a multiple motorized storage
rack installation illustrating one location at which unloading
and loading assemblies may be installed.
FIG. 2 is a fragmentary elevational view, partially
in section, on the line 2-2 of FIG. 4.
FIG. 3 is a fragmentary cross-sectional view on the
line 3-3 of FIG. 2.
FIG. 4 is a plan view of the unloading assembly and
applicable portion of the motorized rack.
FIG. 5 is a plan view of a part of the loading
assembly and applicable portion of the motorized rack.
FIG. 6 is a cross-sectional view of a clutch on the
line 6-6 of FIG. ll.
FIG. 7 is a side elevational view of the clutch
device.
FIG. 8 is a cross-sectional view on the line 8-8 of
FIG. 7.
FIG. 9 is a view similar to FIG. 6 showing the
clutch device in a different attitude of operation.
FIG. lO is a fragmentary plan view, similar to FIG. 5,
but showing a successive step in the loading operation.
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FIG. 11 is a cross--sectional view on the line
11~11 of FIG. 10.
FIG. 12 is a fragmentary plan view of portions
of the unloading and loading assemblies with the loading
assembly in still a further advanced stage of operation.
FIG. 13 is a fragmentary plan view similar to
FIG. 12, but showing a still further advance in the
operation.
FIG. 14 is a fragmentary cross-sectional view on
the line 14-14 of FIG. 13.
FIG. 15 is a fragmentary vertical sectional view
on the line 15-15 of FIG. 14.
DETAILED DESC~IPTION
In an embodiment of the invention chosen for the
purpose of illustration there is shown in FIG. 1 two
endless conveyor racks 10 and 10' in parallel
relationship on each of which is a multiple number of
containers 11, each mounted at its container station 12.
The container stations travel in parallel legs between
opposite ends 13 and 14. In the embodiment chosen, there
is at each end 14 an unloading assembly 15 and a loading
assembly 16. It will be appreciated that, space
permitting, there can be virtually any number of conveyor
racks in such side by side relationship and also that
racks can be arranged in tiers, one above the other, as
suggested in FIG. 11. Further, in the chosen embodiment,
it may be assumed that the endless conveyor racks 10,
10', etc., are traveling in a clockwise direction and may
be so motorized as to be capable of continuous travel at
every level. Although, as illustrated, there is a
container 11 at every station 12, except the left end
station, the conveyor rack is operable in the same
fashion, although additional stations might, on
occasions, be empty.
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THE UNLOADING A',SEMBLY
For the purpose of illustration, it may be
assumed that a container 11' of the endless conveyor rack
lO, at the left end station 12' of the lower leg is
approaching an unloadiny operation to be performed by the
adjacent unloadiny assembly 15.
A loading operation can be presumed to be
imminent by which a container 11'' will be moved into
position to be ultimately loaded on an empty station
12''
To understand the unloading operation, it should
be appreciated that the container 11' is in a sense hung
on the conveyor rack 10 by use of bracket means in the
form of pegs 17, rigidly mounted on side walls of the
container 11' which are received by complementary bracket
means in the form of flanges 18, anchored to columns 19
- of the conveyor. Shelves 20 at the respective stations
12 are for guidance only and not for support of the
containers. Although the containers are shown hung on
the rack, shelf support for the containers would be an
acceptable alternative.
When the container 11' reaches the endmost
position, it will ride over an elevating platform 21, as
shown in FIG. 2 and in plan view in FIG. 4. For lifting
the elevating platform 21 so as to disengage the
container from the conveyor, a lifting cylinder 22
mounted on an adjacent beam 23 is provided with a piston
24 acting against a bracket 25 of the elevating platform,
action of which results in lifting the left edge of the
container 11' high enough for the peg 17 on that side to
clear the corresponding flange 18. Although essentially
a clockwise tilting motion is provided, there will be a
degree of lift for the right-hand wall of the container
11', sufficient to loosen engagement of the corresponding
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peg 17 from its flange 18.
To accentuate the tilt, there may be provided a
substantially vertically extending shaft 26 mounted on
the beam 23, having a bent portion 27 at its upper end.
A lower set of casters 28 are adapted to ride upwardly on
a vertical portion of the shaft 26 while an upper set of
casters 29 ride along the bent portion 27. The net
result of the casters rolling upwardly on the shaft 26 is
to lift the left-hand peg 17, clear of the corresponding
flange 18, sufficient to disengage the container 11' from
its corresponding station 12' so that the container can
be moved clear of the conveyor rack and advance to the
broken line position of FIG. 4. It should be appreciated
that it is unnecessary to lift the right-hand peg 17
clear of its corresponding flange 18 because the
corresponding shelf 20 will be continuing its motion in a
clockwise direction while the lifting is taking place,
the result of which is having the wall of the shelf 20
push the container in a direction from right to left of
FIG. 4 far enough so that upon automatic lowering of the
elevating platform 21, the right-most power actuated
horizontal roller 30 will be engaged by the bottom of the
container 11' and progressively moved in a direction from
right to left, with the help of additional power actuated
horizontal rollers 31, 32, 33, etc., acting as a conveyor
for the unloading assembly 15. The same discharge
disposition of the container would apply under
circumstances where, in the alternative, both rear
corners were released simultaneously instead of by the
tilting expedient.
Synchronization between the travel of the
endless conveyor rack 10, the unloading assembly 15 and
the loading assembly 16, is accomplished, in the
embodiment chosen, by means of a mechanical drive
interconnecting the various moving parts, as illustrated
1~46~
advantayeously in FIG. 4. A common drive shaft 35,
emanating from a conventional source of power, has
mounted thereon a sprocket 36 from which a chain 37
extends to enyagement with a sprocket 37' mounted on a
shaft 38 of the endless conveyor rack. A second sprocket
39 has a chain 40 in engagement with it, the chain 40
being a portion of the endless drive for the conveyor
rack lO. One or more tension sprockets 39' may be
employed to set the tension of the chain 37.
A separate motor 41 mounted on the beam 23 is
provided with shaft 42 which drives a sprocket 43 which
in turn motivates a chain drive assembly 47 for the
rollers 30, 31, 32, 33, etc., which in this fashion
comprise a conveyor for the containers 11 as they are fed
to it by the unloading assembly. Moreover, by an
appropriate selection of sprocket sizes and chain drive
assembly 47, the rollers 30, 31, 32, 33, etc., can be
made to rotate rapidly enough to move the container 11'
along the disposal conveyor at a speed more rapid than
the speed of approach of comparable containers while
being carried by the approaching leg of the endless
conveyor rack. Accordingly, the containers can be moved
out of the way for disposition at a rate faster than they
are unloaded from the conveyor rack. Although a single
common drive shaft 35 has been shown in the chosen
embodiment for operating all levels of the conveyor rack,
there could, where preferred, be a separate motor for
each level.
The same common drive shaft 35, by use of the
chain 37 in engagement with a sprocket 49 on a shaft 50,
can be used for driving appropriate parts of the loading
assembly 16.
THE LOADING ASSEMBLY
If desired, loading of containers on stations of
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the conveyor rack can proceed while unloading is taking
place as well as before or after that operation. For
loading, the containers 11, shown in phantom in FIGS. 5,
lO and 11, for example, may be advanced along an approach
conveyor 56 with the assistance of a set of idler rollers
57. Since the unloading and loading structure and
operation are independent of each other, they could be at
opposite ends, or at both ends, or even at the sides
under acceptable circumstances.
To be certain that each container in turn
reaches loading position with respect to the conveyor
rack at a proper time, there is provided an impeller arm
58 in response to rotation of the shaft 50. In order to
have the impeller arm act at a proper time interval,
there is provided an intermittently actuated clutch 55,
the details of which are shown in FIGS. 6, 7, 8 and 9.
Containers 11 are placed upon an approach conveyor 56
where, riding on idler rollers 57, the container passes
within reach of the impeller arm 58 mounted on the shaft
50. By properly timing manipulation of the clutch 55,
the impeller arm 58 rotates in a clockwise direction, as
viewed in FIGS. 5, lO and 12, to advance the container 11
under power to the loading position of FIG. 12. During
this movement, a caster 59 at the free end of the
impeller arm 58 moves to a position of engagement with
the trailing wall of the container 11, as shown in FIG.
lO, ultimately moving the container to the loading
position of FIG. 12.
As an alternative expedient, by way of example,
a belt type conveyor could be used instead of the idler
rollers 57 to move the container into the proper
position.
The shaft 50, as previously described, is gear
timed in synchronized rotation with respect to travel of
the conveyor rack lO by means of rotation of the shaft
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38. As can be observed in FIG. 4, rotation of the shaft
50 may be made at a rate slower than the rate of travel
of container stations on the conveyor rack. Once the
impeller arm 58 is set in mot:ion by action of the clutch,
it will advance the container at the desired speed to
synchroni~e its arrival at the loading station of FIG. 12
with arrival of the empty station, exemplified by the
shelf 20.
To actuate the clutch, there is provided, as
shown in FIGS. 6 and 8, a solenoid 60, a plunger 61 of
which is projected into engagement with one arm 62 of a
dog 63 so as to move the arm 62 from the clear position
of FIG. 6 to engaged position of FIG. 8 with a cam 64.
In that the dog 63 has its stub shaft 65 in engagement
with the impeller arm 58, the cam 64, being non-rotatably
anchored to the continuously rotating shaft 50, causes
the impeller arm to be moved in a clockwise direction, as
heretofore described. Motion of the impeller arm 58 acts
to build up energy in a torsion return spring 66.
At the end of angular movement of the impeller
shaft 58, as shown in FIG. 12, a camming roller 67, shown
in FIGS. 6 and 9, acting on an arm 68 at the opposite end
of the dog 63, serves to disengage the arm 62 from the
cam 64. ~eleased as described, the return spring 66 acts
to return the impeller arm 58 from the extended position
of FIG. 12 to the initial position of FIG. 5. Once the
dog has been returned to disengaged position by action of
the camming roller 67, a second smaller torsion spring 69
serves to hold the arm 62 out of engagement with the cam
64 until it is again depressed by action of the solenoid
60.
The synchronization between the conveyor rack 10
and the loading assembly 16, together with the unloading
assembly 15, is assured, in the chosen embodiment, by the
endless chain structure which joins the sundry container
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stations of the conveyor rack exemplified by the shelves
20. As can be observed in FIGS. 4 and 13, for example,
links 75 are pivotally connected to adjacent shelves 20
on opposite ends by pins 76. As a result, there will
always be a station on the conveyor at the end of the
loading side opposite a comparable station at the end of
the unloading side, separated by a station facing
endwardly toward the unloading and loading assemblies.
The correct positioning can be assured by the
synchronized timing heretofore made reference to.
Once the container 11 has reached the loading
position, as shown in FIGS. 12, 13 and 14, a transversely
acting mechanism 77 forming part of the loading assembly
16 is called upon to place the container in position on
the appropriate station 12 of the endless conveyor rack
10 .
As the container, after traveling along the
approach conveyor 56, reaches approximately the phantom
position of FIG. 10, the empty station, exemplified by
the shelf 20, will have reached approximately the
position shown in FIG. 10. In this position, the inside
corner of the leading edge of the container will commence
to closely approach the empty station 12, exemplified by
the shelf. As the container continues to be pushed into
the loading position by action of the impeller arm 58,
the shelf 20 will continue turning until it reaches the
position of FIG. 12. At the same time, the container 11
will have been pushed into the position shown in phantom
by pressure of the caster 59 of the impeller arm 58, but
the peg 17 at the inside corners of the container will
not have as yet engaged with the flanges 18 of the
conveyor rack. Engagement is accomplished by action of
the transversely acting mechanism 77.
THE TRANSVERSELY ACTING MECHANISM
Essential portions of the mechanism 77, shown in
plan view in FIGS. 12 and 13 and in substantially a
sectional view in FIG. 1~, are embodied in a power
cylinder 78 pivotally mounted on a horizontal beam member
87, a plunger 79 of which is secured to a bracket 80
attached to a loading bar 81. The loadiny bar is
provided with a loading tray 82 adapted to slide under
the outside of the container 11 to make certain that it
can be lifted to the proper position for ultimate loading
at the selected station. To provide for accurate
movement of the loading tray 82, there are provided two
linkages, on respectively opposite sides of the power
cylinder 78. On the left side, a central link 83 is
attached by a short link 85 to the loading bar 81 and by
another short link 86 to a stationary horizontal beam
member 87. Similarly, on the right side, as viewed in
FIG. 12, a central link 84 is attached by means of a
short link 88 to the loading bar 81 and by a second short
link 89 to the horizontal beam member 87. The
parallelogram effect of the two sets of links maintains
the loading bar 81 and loading tray 82 in a proper
position of alignment as the loading bar and loading tray
are pushed from the position of FIG. 12 to the position
of FIGS. 13 and 14. Further, by reason of tilting the
25 transversely acting mechanism 77 obliquely upwardly, as
shown in FIG. 14, the outside edge of the container 11 is
lifted from the broken line position of the loading tray
82 to the solid line position of the same tray 82, thus
providing an upward tilt for the outside edge of the
30 container 11.
As the outside edge is being lifted in the
manner shown, the container at the same time is being
moved in a direction from left to right, as viewed in
FIG. 14, from the broken line position to the solid line
position. Movement as described causes the pegs 17 to
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11
first engaye a camming slope 90 of the respective flange
18 so that the pegs will ride over the camming slope and
lodge behind the flange 18 in each case in the manner
shown in FIG. 14. Once behind the flange, the container
can drop to a position of engagement with a ledge 95
where it is positioned by a stop 96.
By the procedure just described, the container
11 is hung in proper position on the empty station 12 of
the conveyor rack which has been provided for it. The
loading tray 82 is then withdrawn by reverse action of
the power cylinder 78 so as to be receptive of the next
container 11 which becomes moved to loading position for
a succeeding empty station.
In the chosen embodiment of the invention pegs
17 and flanges 18 have been relied upon as a simple
effective expedient for attaching the container to the
rack at the proper location. It should be appreciated
that what is important to the invention is to have the
attachment a releasable attachment, irrespective of the
expedient chosen. Various alternatives may be preferred
as, for example, making use of a spring actuated flange,
or instead a spring activated peg. Another alternative
is one in which a movable hook may be employed on the
rack to releasably engage an appropriate hole in a rim 97
f the container, or other comparable structure on the
container.
It should be borne in mind in connection with
the operation for loading just described that the shelf
20 is continuously moving, first around the end of the
conveyor rack to the loading position, and thereafter
immediately in a direction from left to right along the
corresponding leg of the rack. The container arrives at
the loading position in advance of arrival of the empty
station by a sufficiently brief time span to make certain
that there is proper alignment when the power cylinder 78
4~i2X
is triggered to push the container into the station and
engage the peys 17 with the flanges 18. It should be
appreciated in this context that when the container
arrives at the loading position, the inside edge of the
container is only a short distance from the conveyor rack
so that the distance can be immediately closed and
engagement accomplished in a very brief span of time.
As an additional assurance that the entry will
be timely, there may be provided tapered edge sections 91
and 92 at the ends of the shelf 20 for guidance.
Although reference has been made to the
containers 11 in a manner directing attention to the
inside edge of the container as being provided with pegs
17, it should be noted that comparable pegs 17 are also
provided at outside ends of the side walls and pegs 17'
at opposite ends of both the front wall and back wall of
the container. Having the container equipped in this
fashion with multiple sets of pegs 17, a square container
can be loaded on and carried by appropriate stations 12
of the conveyor rack in any one of four orientations,
since all pegs 17 and also the pegs 17' will engage with
the flanges 18 in the same fashion. The pegs as shown
are located beneath the rim 97 which extends around the
top of the container.
While a particular embodiment of the present
invention has been shown and described, it will be
obvious to those skilled in the art that changes and
modifications may be made without departing from the
invention in its broader aspects and, therefore, the aims
of its appended claims are to cover all such changes and
modifications as fall within the true spirit and scope of
this invention.
Having described the invention, what is claimed
as new in support of Letters Patent is as follows:
