Note: Descriptions are shown in the official language in which they were submitted.
BAC~GRo~1ND OF THE INVE~lT:ION
The present invention relates to means for sequentially
transferring a group of articles in an article manufacturing
operation from one conveyor to another. ~ore particularly,
it relates to a means for ef~iciently and effectively
transferring articles in sequence from a straight line
conveyor moving at one speed in one direction to a row
conveyor moving in a differing direction and at a differing
speed.
The manufacture of metallic objects including closure
cap covers and the like has normally used certain steps
in their manufacture to trans~er the articles from one
conveyor to another. Such transfers have previously been
accomplished for example, by physically engaging the articles
with guides or plungers or other transfer means to push the
articles from one conveyor to another conveyor, Certain
articles are transferred only with considerable difficulty
by these prior devices, and in particular, relatively flat
articles are not effectively transferred by known apparatus,
Also, present transfer devices do not handle articles with
wet or uncured gaskets or coatings on thPir surfaces without
damaging these coatings or gaskets~ A closure cover which
is relatively flat and which also has a ring-like gasket on
its upper surface and which is normally transferred duxing
cap manufacturing from a single line conveyor to an oven
row conveyor while the gasket is still liquid, is
illustrated, for example, in United States Patent 3,913,771
dated October 21, 1975.
The apparatus of the present invention provides for
an effec-tive and rapid sequential trans~er of such articles
from one conveyor to another conveyor and par-ticularly from
single line conveyors to row-type conveyors.
This transfer is made by the improved apparatus of the
present invention by means which magnetically and sequentially
engages and lifts a group of articles from one conveyor and
which then moves them to the second conveyor along a path and
at a velocity which matches that of the article receiving
conveyor. The second conveyor, for example, may be a row
conveyor for an oven or other article treating means which
cures or otherwise treats the gasket portion or other portions
of the transferred articles.
~n improved transfer apparatus is described for intermitt-
ently transferring rows of magnetically engageable articles
from a straight line conveyor to a row conveyor comprising
the combination of means for movably supporting a plurality
of electromagnets, and means for mounting and for driving
said supporting means for movement on a path from a posi-tion
~0 above one said conveyor to a position above the other said
conveyor.
Said driving means comprises a drive motor operatively
coupled to said electromagnet support means for moving it
:Erom one of said positions to the other. Said eletromagnet
support means is an elongated member with said electromagnets
being mounted in spaced relation in a row thereon with ' `
circuit means for sequentially energizing said elec-tromagnets
including means for detecting the first arriving article
on said straight line conveyor and for energizing the second
electromagnet in the row of electromagnets and with means
for detecting said late arriving articles and for
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sequentially energizing said additional electromagnets in
the row.
BRIEF DESCRIPTION OF T~E
DRAWINGS
A preferred embodiment of the invention has been
chosen for purposes of illustration and description and
is shown in the accompanying drawings, forming a part of
the specification, wherein:
FIGS. 1 and 2 are top plan views of the preferred
embodiment of the transfer apparatus of the present invention
in the cap pick-up and release positions, respectively.
FIGS. 3 and 4 are side elevational views of the
transfer apparatus of FIGS. 1 and 2 in the successive
positions.
FIG. 5 is a schematic diagram of the electrical control
system for the transfer apparatus of the present invention.
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6~;5
FIG, ~ is a loyic diagram for the control system
of the present invention.
DESCRIPTION OF THE PREFERRED EMBoDIr5ENT
_
The drawings illustrate à preferred embodiment of
the invention for transferring metallic objects such as
closure cap covers from a straight line conveyor to a
row conveyor. The particular example illustrated shows
an apparatus 1 for transferring metal closure covers 2 having
ring-like gaskets 3 on their upper surfaces from the gasket
applying station ~ to a gasket-curing oven-8. The closure
covers 2 are carried to the transfer means 1 on the straight
line conveyor with random spacing and with the gasket 3
still soft and uncured.
The transfer apparatus 1 periodically removes the
endmost group of closure covers 2 from the single line
conveyor 5 and carries them to a broad belt or row conveyor
7 ofa gasket curing oven 8. On the row conveyor 7, spaced
rows of closures are advanced through the curing oven ~.
The transfer means includes an elongated transfer
bar 9 mounting a number of electromagnets 10, The transfer
bar 9 is slidably mounted on transverse bearing rods 11 to
permit the magnet transfer bar 9 to be moved from the pickup
positiGn illustrated in FIG. 1 to the release position above
the row conveyor 7 as illustrated in FIG. 2. The movement
of the transfer bar 9 between these two positions is done
by a suitable drive cylinder such as the air operated
cylinder 14.
An electrical system is provided which energizes
the magnets 10 in a sequential ~anner under the control of
the arriving closure covers 2. This system, which wi.ll be
further described below, has proximity detectors 12 at each
electromagnet. As the endmost closure cover 2 on the
straight line conveyor 5 reaches the endmost electromagnet
10 its proximity sensor detectors 12 activate that magnet 10.
At the same time this sensing circuit then energizes the
second electromagnet detecting system so that the arrival
of the next closure~-cover-2 at the second electromagnet 10
proximity detector 12 energizes it. This proceedure
occurs successively or sequentially for:each of the suFceeding
electromagnets 10 until a closure cover 2 is detected and
engaged by the last electromagnet 10, When the last losure
cover 2 has been detected and engaged the circuit energizes
the power cylinder 14 which moves the transfer bar 9 from
the single line conveyox at the position illustrated in FIGS,
1 and 3 to the release position lllustrated in FIGS. 2 and 4,
The transfer bar 9 is mounted on a pair of spaced
slide bearings 15 on slide rods 11. This permits the transfer
bar 9 to be moved from a position above the straight line
conveyor 5 as illustrated in FIGS. 1 and 3 to a position
above the row conveyor 7 as illustrated in FIGS. 2 and 4,
The transfer bar 9 has a bearing 15 mounted at each end
which slidably supports the transfer bar on the spaced
slide rods 11. The drive cylinder 14 is mounted on a suit-
able support frame 17 and its piston 18 is pivotally
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attached at l9 to the tra~sfer bar 9.
The straight line conveyor 5 continues to present
the closure cap covers 2 to a transfer position below the
transfer bar 9. During the transfer cycle, the tra~sfer
bar 9 returns from a prior cover transfer to its pickup
position before the endmost cap cover 2 is moved on conveyor
5 beneath the end magnet lO on the transfer bar 9. When this
cover 2 arrives at a transfer position on the straight line
conveyor 5 and adjacent to the end magnet lO on the transfer
bar 9, it is detected by the proximity detector 12 for
energizing the related electromagnet closure cap pickuplO.
The following closure caps moving on the single line conveyor
5 successively activate the second and third and the additional
eleetromag~Qts lO in the same manner.
When a closure~cap cover 2 has activated the last
deteetor 12 on the transfer bar 9, that closure cap cover 2
is engaged by a related electromaqnet lO and the transfer
bar 9 is moved by the drive cylinder 14 to carry all of
the engaged closure cap covers 2 from the straight line
conveyor 5 to the cap release poirt above the row conveyor 7,
When the transfer bar reaches this point it operates the
elosure eover release switchLS2 to deactivate all of`the
eleetromagnets lO and to drop all of the transferred closure
covers 2 to the row conveyor 7 for movement through the
curing oven 8.
THE ELECTRO.~AGNET CONT~OL
CIRCUIT
The electromagnet control circuit 21 for the cap
transporting magnets 10 is illustrated in PIG. 5 and the
related logic diagram is shown in FIG. 6.
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The magnet control circuit 21 is powered by a
regular commercially available power circuit such as a 115 volt
A.C. circuit 22. This power circuit includes an on-off switch
23, and a fuse 24 and an indicator lamp 37. A number of control
amplifiers 25 and a D.C. rectifier 26 are illustrated connected
across the power circuit 22.
The rectifier control circuit 26 converts the 115
volt A.C. power supply to a 24 volt D.C. power source for the
cap transfer magnets 10.
Described generally, the control circuit 21 operates
as follows. Each of the amplifiers 25 controls one of the cap
piekup magnets 10. When the transfer bar 9 is adjacent to the
straight line conveyor 5, a fixst ampl1fier 25 is energized
so that its sensor 12 closes the relay contacts 27 for activating
the next-amplifier 25 and contacts 28 for connecting the first
pickup magnet 10 across the 24 volt D.C~ rectifier output. With
the second amplifier 25 now activated, its sensor 12 upon
detecting the next closure cap 2 in line, closes the relay
contacts 29 to activate the third~amplifier 25 and contacts 30
to energize the seeond cap pickup magnet 10. This action
continues for eaeh of the suceessive ampliflers 25 and the asso-
eiated cap pickup magnets 10. The last amplifier 25 in the line
operates the control relay CRl for closing the air motor 14
eontrol valve 31 for advancinq the transfer bar 9 to its cap
release position over the row conveyor 7. The advancement of
the transfer bar 9 to this position opens switehes LS2, L53 and
LS4 to deactivate the magnets 10 for releasing the caps 2 and
to open the air motor control valve 31 while elosing the second
return control valve 32 causing the air motor 14 to return the
transfer bar 9 to its cap pickup position above the qtraight
line conveyor 5.
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The above circuit and its operation will now be
described in greater detail with reference to the schematic
diagram FIG. 5 and the related logic diagram FIG. 6.
Refer~ing to the upper left hand corner of FIG. 6 and
to the identified components of FIG. 5, the sequence is
initiated with the transfer bar 9 at its pickup position above
the straight line conveyor 5~ At this point, the limit switch
Lsl is closed through contact with the transfer bar 9. Limit
switches LS2, LS3 and LS4 have normally closed contacts which
remain closed for this position of the transfer bar 9. This
position of these limit switches energizes the first amplifier 25
and the associated sensor 12 so that it is in a position to
detect the first closure cap 2 to arrive on the straight line
conveyor 5. Upon the detection of the first closure cap 2 the
contacts 27 in the first amplifier 25 are closed causing the
next amplifier 25 to be activated and causing the first pickup
magnet 10 to be energized by being coupled to the output of
the rectifier 26. A similar amplifier activation and pickup
magnet energizing now occurs successively for the number of
amplifiers used which corresponds to the number of pickup magnets
illustrated as eleven in FIG. 1, When the sensor 12 for the
last amplifier 25 detects a cap 2, it energizes the last
pickup magnet 10 and, since li~it switches LS3 and LS4 are
close~, its contact 29 activates both the air mo~or advance valve
31 and relay CRl~ The transfer bar 9 is now moved by the air
motor 14 to its cap release position over the row conveyor 7
at which position limit switch LSl reopens and limit switches
LS2, L53 and Ls4 are opened, This opens the relay CR2 to turn
off the amplifiers 25 to release the closure caps 2 from the
transfer har 9, and closes the valve 32 for again returning
the transfer ~ar 9 to its position above the straight line
conveyor 5 for the next transfer cycle,
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The magnets may have a small reverse current bias
effective when the plus 24 volts is removed to insure a quic~
cap release or a small negative voltage may be applied at the
release time by the rectifier 26.
It will be seen that an improved cap transfer device
has been described as advantageous for use with caps arriving
on one conveyor with random spacing, such as a straight line
conveyor, and for transferring them to a second conveyor,
where the caps are aligned in regular rows. The i~proved
transfer device, including its control circuit, is relatively
simple yet reliable and effective for continually performing
such a cap transfer.
As various changes may be made in the form,
construction an-d arrangemen-t of the parts herein without
sacrificing any of its advantages, it is to be understood that
all matter herein is to ba interpreted as illustrative and not
in a limiting sense.
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