Apparatus for palletizing pressings

Apparatus for palletizing the pressings being delivered in succession by a transfer press system either individually or in closely positioned pairs. Included are separators for separating each closely positioned pair of pressings away from each other while they are being transferred along a predetermined path from the final press station to a stacking station. At the latter station the successive pressings are deposited on a carriage to form one or two stacks thereon. The carriage transports the stack or stacks of pressings to a pickup station, where the stack or stacks are picked up from the carriage by a loader or loaders, thereby subsequently carried to a loading station or stations, and loaded on a pallet or pallets. As disclosed, the apparatus further comprises a system of conveyors for transporting empty pallets to, and loaded pallets from, the loading stations.

BACKGROUND OF THE INVENTION 
This invention relates in general to apparatus for loading articles on 
pallets, and in particular to apparatus suitable to be incorporated with a 
transfer press system for automatically palletizing the pressings being 
delivered thereby. 
As is well known, the transfer press system is a streamlined machine having 
a succession of press stations through which workpieces are transferred 
one after another for the continuous fabrication of various panel 
products. The palletization of the pressings of varied shapes and sizes 
made by the transfer press system requires apparatus specially designed to 
this end. 
A difficulty arises in connection with the palletization of the pressings 
as each workpiece may be either wholly processed into a single pressing or 
split into a pair of pressings by the transfer press system. Further the 
workpieces may be split either longitudinally or transversely with respect 
to their traveling direction through the press line. Each closely 
positioned pair of pressings, formed by the severance of a workpiece, must 
be spaced away from each other preparatory to palletization. 
SUMMARY OF THE INVENTION 
The present invention provides apparatus for efficiently palletizing the 
pressings made by a transfer press system, with facilities for separating 
each closely positioned pair of pressings prior to palletization. 
Broadly the palletizing apparatus in accordance with the invention is 
intended for use with a transfer press system which fabricates and 
delivers a succession of pressings either individually or in closely 
positioned pairs. The palletizing apparatus includes transfer means for 
transferring the pressings along a predetermined path to a stacking 
station. Disposed on the path of the pressings are means for separating 
each closely positioned pair of pressings away from each other as 
required. At the stacking station the transfer means deposit the 
successive pressings on a carriage to form one or two stacks thereon. The 
carriage transports the stack or stacks of pressings to a pickup station. 
Loader means pickup the stack or stacks of pressings from the carriage at 
the pickup station and transport the same to a loading station or stations 
for loading on a pallet or pallets. 
Other features and advantages of the present invention will become 
apparent, and the invention itself will best be understood, from the 
following description and appended claims taken together with the attached 
drawings showing a preferred embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The palletizing apparatus embodying the principles of the invention is 
generally designated 10 in FIGS. 1 and 2 and is therein shown appended to 
the output end of a known transfer press system 12. The transfer press 
system is conventionally equipped with a work indexing mechanism 
comprising a pair of parallel spaced transfer bars 14 extending 
longitudinally of the press system. Also as is well known, the work 
indexing mechanism has means, not shown, for moving the pair of transfer 
bars up and down, toward and away from each other, and back and forth. By 
the repetition of these motions in a prescribed sequence the transfer bars 
act to transfer successive workpieces W through a series of press stations 
designated A, B, C, D and E. Further the transfer bars function to feed 
the workpieces one by one into the press line from their piles indicated 
at W' in FIG. 2, and to deliver the completed pressings P from the final 
press station E to the palletizing apparatus 10 of this invention. 
The palletizing apparatus 10 in accordance with the invention has six 
processing stations in series arranged posteriorly of the press stations A 
through E. These are: 
1. First and second separating stations I and II, immediately following the 
final press station E, where each closely positioned pair of pressings are 
separated from each other. 
2. A stacking station III where the pressings P, including those which have 
been separated at the separating stations, are stacked on a carriage 16. 
3. A pickup station IV where the stack or stacks of pressings on the 
carriage 16 are picked up by a loader or loaders 18. 
4. Two loading stations V and VI where the stack or stacks of pressings are 
loaded by the loader or loaders 18 on a pallet or pallets 20. 
An inspection of FIGS. 1 and 2 will indicate that the pair of transfer bars 
14 of the transfer press system 12 has leftward extensions 14'. The 
transfer bar extensions 14' terminate at, or just beyond, the stacking 
station III. The pressings P are transported from first separating station 
I to stacking station III by the transfer bar extensions 14'. 
As seen in FIGS. 3A, 3B and 3C, a set of skid bars 22 are disposed at the 
two separating stations I and II. The skid bars 22 lie between the pair of 
transfer bar extensions 14' and extend along the same in parallel spaced 
relation to each other. An oppositely threaded rod 24 extends across the 
skid bars 22 and is threadedly engaged therewith. One end of the threaded 
rod 24 is coupled to a reversible electric motor 26. Thus, upon rotation 
of this motor in opposite directions, the spacings between the skid bars 
22 are infinitely variable to adjust to the transverse dimension of the 
pressings P or to the distance between the pair of transfer bar extensions 
14' when these are moved toward each other. 
FIGS. 3A through 3C are also explanatory of the manners in which various 
types of pressings travel through the separating stations I and II. If the 
pressings P have been fabricated by the transfer press system 12 each from 
one workpiece W, as in FIG. 3A, then such pressings are just carried 
through the separating stations I and II to the stacking station III by 
carriers 28 affixed to the transfer bar extensions 14', without in any way 
being processed while being so transferred. 
In FIG. 3B are shown a separator mechanism 30 and carriers 28a attached to 
the pair of transfer bar extensions 14' for use with closely positioned 
pairs of pressings P each formed by transversely splitting a workpiece at 
the final press station E as will be seen by referring back to FIG. 1 or 
2. The separator mechanism 30 comprises a pair of grippers 32 on each 
transfer bar extension 14' which are movable toward and away from each 
other in the longitudinal direction of the transfer bar extension. Gripped 
by the two pairs of grippers 32, each closely positioned pair of pressings 
are separated a required distance away from each other while being 
transferred from final press station E to first separating station I. 
After landing on the set of skid bars 22 at the first separating station 
I, the successive separated pressings P are carried through the second 
separating station II to the stacking station III by the carriers 28a on 
the transfer bar extensions 14'. 
Each workpiece may be split at the final press station E into a pair of 
pressings longitudinally with respect to its traveling direction. Each 
closely positioned pair of pressings thus formed must be transversely 
separated away from each other. FIG. 3C shows at 30a a separator mechanism 
used to that end. The separator mechanism 30a comprises a pair of grippers 
32a mounted on the respective transfer bar extensions 14' for movement 
toward and away from each other. The grippers 32a move each closely 
positioned pair of pressings away from each other to a required degree at 
the first separating station I. Then the transversely separated pairs of 
pressings are carried through the second separating station to the 
stacking station III by carriers 28b on the transfer bar extensions 14'. 
As will be seen by referring back to FIG. 2 in particular, the successive 
pressings P are to be stacked on the carriage 16 at the stacking station 
III. FIG. 4 illustrates the carriage 16 in more detail. It is wheeled as 
at 34 for rolling along a pair of horizontal rails 36 between stacking 
station III and pickup station IV. Mounted on the carriage 16 are a 
plurality of parallel spaced bars or plates 38 on which the pressings are 
to be deposited from the pair of transfer bar extensions 14'. The spacings 
between these bars are variable by a threaded rod 40 rotated by a motor 
42, as required by the size of the pressings to be stacked thereon. 
Disposed under the carriage 16 at the stacking station III is a lifter 44 
for lifting the carriage to a predetermined level prior to the 
commencement of the stacking of the pressings thereon. As the successive 
pressings are deposited on the carriage 16 from the transfer bar 
extensions 14', the lifter 44 gradually lowers the carriage in order that 
each pressing may fall the same distance from the transfer bar extensions 
onto the pressings already stacked on the carriage. Thus is formed one or 
two stacks of pressings P on the carriage 16. 
When loaded fully, the carriage 16 is lowered by the lifter 44 into rolling 
engagement with the pair of rails 36. Then the carriage 16 transports the 
stack or stacks of pressings from stacking station III to pickup station 
IV. 
The transfer press system 12 continues the fabrication and delivery of 
pressings while the carriage 16 is away from the stacking station III. The 
pressings being released from the transfer bar extensions 14' at the 
stacking station during this period of time must be received and held by 
means other than the carriage 16 pending its return to the stacking 
station. 
FIG. 4 also shows a fork assembly 46 provided for the above purpose. Lying 
just under the transfer bar extensions 14', the fork assembly is thrusted 
by a fluid actuated cylinder 48 to a working position at the stacking 
station III upon full loading of the carriage 16. The pressings 
subsequently released from the transfer bar extensions 14' are stacked on 
the fork assembly 46. When the carriage 16 returns unloaded from the 
pickup station IV and is raised by the lifter 44, the fork assembly 46 
reloads the stacked pressings on the carriage. Thereafter, with the 
contraction of the cylinder 48, the fork assembly moves to a retracted 
position, allowing the subsequently released pressings to stack on the 
carriage 16. 
FIG. 5 is a detailed illustration of the loaders 18 for transferring the 
stacked pressings P from the carriage 16 at the pickup station IV onto the 
pallets 20 at the loading stations V and VI. Each loader comprises a 
wheeled, self-propelled carriage 50 movable along a pair of rails 52 laid 
horizontally at a required height above the plant floor. Depending from 
the opposite sides of the carriage 50 are a pair of arms 54 which are 
jointly movable up and down relative to the carriage by a fluid actuated 
cylinder 56 and at least one of which is further movable toward and away 
from the other by a bidirectional electric motor 58. The pair of depending 
arms 54 have foldable end members 60 mounted on their bottom ends for 
pivotal motion between vertical and horizontal positions by fluid actuated 
cylinders 62. 
If only one stack of pressings is formed on the carriage 16 at the stacking 
station III and thereby carried to the pickup station IV, as in the case 
of the pressings explained in connection with FIG. 3A, then one of the 
loaders 18 is sent to the pickup station for picking up the stack of 
pressings P from the carriage 16 by the pair of depending arms 54, with 
their end members 60 folded inwardly as depicted by the solid lines in 
FIG. 5. The loader 18 subsequently travels back to either of the loading 
stations V and VI to load the stack of pressings P on a pallet 20. 
If two stacks of pressings are formed on the carriage 16 at the stacking 
station III, both loaders are caused to travel to the pickup station IV 
for picking up the respective stacks from the carriage. The loaders may 
then be moved to the loading stations V and VI for loading the stacks of 
pressings on pallets 20. 
The present invention further contemplates the provision of a conveyor 
system for the transportation of empty pallets to, and of loaded pallets 
from, the two loading stations V and VI. FIG. 6 illustrates the conveyor 
system in detail. Generally designated 64, the conveyor system comprises 
an infeed conveyor 66 and a delivery conveyor 68 disposed in parallel 
spaced relationship to each other on opposite sides of the pair of rails 
52, FIG. 5, along which the loaders 18 reciprocate between pickup station 
IV and loading stations V and VI. As the names imply, the infeed conveyor 
66 function to carry successive empty pallets 20 toward the loading 
stations V and VI, and the delivery conveyor 68 to carry loaded pallets 
away from the loading stations for storage or shipment. 
Arranged between the infeed 66 and delivery 68 conveyors are a first branch 
conveyor 70 extending across the first loading station V and a second 
branch conveyor 72 extending across the second loading station VI. At the 
junctions of the infeed conveyor 66 and the two branch conveyors 70 and 72 
there are provided turn conveyors 74 and 76 of short extent on respective 
platforms 78 and 80 for the right-angular change of direction of the empty 
pallets from the infeed conveyor to the branch conveyors. Similar turn 
conveyors 82 and 84 are mounted on respective platforms 86 and 88 at the 
junctions of the delivery conveyor 68 and the two branch conveyors 70 and 
72 for the right-angular change of direction of the loaded pallets from 
the branch conveyors to the delivery conveyor. 
Thus the successive empty pallets 20 travel to the right on the infeed 
conveyor 66. At its junctions with the branch conveyors 70 and 72 the turn 
conveyors 74 and 76 transfer the empty pallets from the infeed conveyor 
onto the respective branch conveyors. The branch conveyors 70 and 72 carry 
the empty pallets to the respective loading stations V and VI. On being 
loaded with the pressings at these stations in the above described manner, 
the pallets travel on the branch conveyors 70 and 72 toward the delivery 
conveyor 68 and ride thereon with the aid of the turn conveyors 82 and 84. 
Then the delivery conveyor 68 transports the loaded pallets toward a place 
of storage or shipment. 
The foregoing disclosure will have made clear that there has been invented 
apparatus which will greatly expedite the palletization of the pressings 
made by a transfer press system. The apparatus lends itself to automation, 
as will be readily recognized by the specialists. A variety of 
modifications and alterations may also be contemplated and resorted to by 
one skilled in the art without departing from the spirit or scope of the 
invention as expressed in the following claims.