Note: Descriptions are shown in the official language in which they were submitted.
1~8~438
Improvements Relating to the Handling of Sheet
Materials
05 This invention relates to the handling of sheet
materials, and more particularly conce~ns the handling
of indi~idual sheet artic}es such as labels~ tickets,
coupons or the like by appropriate maohinery in order
to transport and transfer the sheet materials from o~e
surface or location to another.
In, for exampleq the application of individual labels
to bottle~ or articles in a mechani~ed process, there
arises freq~ently the need to handle and transfer the
labels from one location to anotherD Specifically, in
an area in which we are interested, individual ~abels
are cut from a web of material leaving a skeletal
wast0. and the labels are held by mean$ of a drum or
plate which moves so as to moYe the cut labels in a
path whioh is dif~erent from the path of travel of the
~keletal waste~ Sub~equently, the :Labels are re~oved
from this oarrier and are either applied directly to
articles or are kransferred by an intermedi~te carrier
to a loaation where they are applied to said articles.
z5 In this connection, one face of the labels ~ay be
provided with an ~dhesiYe which is either pre-aPplied
or subsequently appliedO The form o~ adhesiYe is ~ot
of particularly ~nate~rial considera~ion in rel~tion to
the present invention, but i~ may be for example
30 pressure sensitive adhesive or heat activated adhesive
or indeed water activated adhesive and will be to the
outer surfaee of the label in relation to the carrier
which transports the label.
In our European Patent Application No. 8230~5057 we
have set forth one method of detaching labels from a
rotary vacuum drun~. The labels are held to the drum~
~2~3X~3~3
'
surface 'chrough suitable ports to which a Yacl1um is
app~!iedq but when the label reaches a posi~ion wbereat
detachment is required. air under pressure is applied
through some of 'chese p~rts in an attempt t~ blow the
05 label from the drum surface and directl~ onto an
artiele moving in synchronism with the drum~ It has
been found in experimenting with ard developing such a
sy~stem that because of the por'c design size of
aperture. in fact there is no blowing away OI the label
from the drum, but rather what appears to ~appen is
that a film or layer of air exist~ under t~e label in
'che region of the ports through which the pressure air
i5 blown. and the label simply lifts from the drum
surfac~, to a very small extent i~e. of the order ~f' 1
15 mm. and is not physically blown ah~ay ~rom the drum
~urface~ which indeed is what is require~.
In con~equenae., in some cases where the labels should
leave the drum. and it should be borne in mind that the
20 drum may be handling labels at 'che rate o~ 200 per
minute, such labels do not leave the drum and
consequently there is fouling and severe ~lockage of
the apparatu~.
.
The present ln~ention was made in an eîfort t~ overcome
~this diffi~ulty~ and whilst its i0mediate ~se will be
in relation to the apparatus in which we are interested
i.e. the handling of labels by rotary vaouum drums~ it
will be appreciated that it is not neces ary that the
39 invention should be so limited to suoh speoific
appl i cati on D
Varlous experiments and trials were conduc~ed before
the present invention was finally reached. In
35 particular~ in a f irst experimenS, the ports through
which the air blast was conducted were surrounded by
annular ports through which low pressu~e air was
'~LZ~3Z'~
conducted in an effort more positively to detach the
labelsO but this experiment produced no lmproYed
effect~ Seco~dly, instead of utilising apertures to
form the ports, the said ports were defined by sintered
05 metal plugs in an effort to provide greater air
distribution, but again this experim~nt ~Jas
unsuccessful~ ~hirdly, a channel was formed around
the exi~ port~ in an effort to provide a body of
pres~ure air ir. free space, but again this development
proved ~nsuccessf~1.
The presen~ invention however has shown itself to be
extre~ely useful for the purpose. and in accordance
with the present invention the method comprises
detaching a sheet element from a support surface having
a plurality of apertures therein throug~ which pressure
air oan be supplied in order to detach at least one
edge of the sheet, the method residing in that pressure
air is supplied to porting in a region which is
inwardly spaced of the edge of the she!et material to be
detached, followed by injection of higher pressure air
through porting which the edge to be detached overlies,
This arrangement has been shown to work extremely well
insofar as when the lower pressure air is applied to
the sheet inwardly of the edge thereo~, the sheet lifts
from the surfaoe at that point, and when the subseq ue nt
blast of air is applied to the portlng oo~ered by the
edge, then that edge is positively and clearly blown
away from the surface. Once the edge of the shcet
material is thus separated from the sur~ace, it then
becomes a relatively easy matter to control the
positive displacement of the entire sheet from the
surface. For example~ a paring knife edge can engage
under the detached sheet edge preventing it from
returning to the said surface.
~2~3Z~38
4 -
In speci~ic application, the said surface supporting
the sheet will be movable, and preferably will be a
rotary drum to which individual sheets are applied in
- turn and are removed i n turn, and i n one exampla the
said drum co~prises a vacuum drum provided with a
plurality of rows of vacuum ports to which vacuum can
be applied in order to hold the sheets thereto whilst
the ~heet3 travel between an application location and
the detachment location, but which at the detachment
10 location can become the ports which are pressuri~ed in
accordance with the method of the prssent invention.
In a ~peci~ic example, if one consider~ that the drum
is handling labe~ and the labels ~or simpllci~y!s ~ake
l~ are re¢tangular with the loDger side~ exte~ding ax~lly
of the drum, each label in relation 1;o the direction oP
. rotation of the drum will havs ~ ~sading edge and a
trailing edge. In the specific applicat;ion o~ the
~ethod of the invention, the leading edge will be the
20 edge which is detached in accc,rdance with the
invention, and the first ro~ of pOl't3 which is under
the leading edge of the label will ~t the appropriate
time have the inJection o~ air under pressure, but the
second row w~ll be provided with air under presqure
~rst/ and at a difPerent ~lower ar higher) pre~sure~
Suitable coupl~ng porting must be provided on the
mo~t~g~ ~or the drum to ensure t:hat thi~ happen~
because in 'che operation of th~ particular apparatus,
normal ly the port~ will be connec~ed to a source of
vacuum ln order that the la~el3 will be held to the
drum as they ~ravel between the application location
and the detachment looation, but when thè ~irst and
second rows of ports reach the application location,
air under pres~ure is to be supplied thereto a~
described above. Equally, the third and subsequent
rows of ports covered by the label are coupled to the
~ource of pre~sure a~ kh_ said rows pass the
~2824~8
app~ication location.
The inventio also provides apparatus constructed to-
operate in accordanae with the method.
û5
The method has show n itself to be extremely use~ul in
high speed label application situations. especially
when a rotary drum is used f or the transport of the
labels between attachment and detaohment location~
10 spaced relative to the drum periphery.
The method may be used ln coniuncSion with suitable
knife means to assist the detachment cf the labels ~rom
~he surface~ and such knife means m~y comprise a
15 mechanical knife member. or for exan~ple an air knife
ar~angementO
It will be appreciated that the invention can be
applied for the handling of other sheet elements apart
20 ~rom labelsO a~d also ~hat the labels to be handled can
be of any size and configuration. ~'he labels may be
the so-called patch labels or wrap round labels the
latter being of a type to be wrapped completely round
the articles to which they are to he app~iedi
The method of the invention can be utilised for the
handling of sheet materials which are ~elicate and
flimqy as the vacuum and positiYe pres~ures can be
controlled as desired. Also. as air will be the most
30 likely gas to be used for the creation of the vacuum
and air pressure. it is to be appreciated that any
gaseous medium can be used.
An embodiment of the invention will now ~e described,
35 by way of exampleO with reference to the accompanying
diagrammatic drawings. wherein:-
~ ~8Z438
FigD 1 is a perspective vi ew of an arranger~en~according to the present invention;
Figo 2 is a development Yiew show ing the vacuum drum,
05 and the valve drum in opened out condition; and
Figs~ 3 and 4 show how a label is separated from tbe
va~uum drum in aocordance with the ~ethod of the
inY enti os~ D
Referring to the drawings. in Fig~ 1 there is shown a
vacuum drum îU which co-operates w:ith a die cutting
drum 12. khese drums being rotatable as indicated by
the arrows~, and defining there-between a outting lip
15 ~hrough which a web '14 having labels 16 defined thereor,
pass~ B .
The web 16c is as disolosed in our European Patent
Application No. 82~065057 and has pressure sensitive
adhe~ive on side 18. and a re~ease ooat on ~de 20 so
that tbe release coat in faet covers the label printin~
16 and enableY the web 14 to be wound intu roll form
without the use of a backing web. AdditionalIy.
although lt formg ~lO part of the present invention, the
25 s~eb 14 has sprocket drive apertures .~2 along the edges
' 'chere~fD
As the web passes through the nip between drums 10 and
12. the web moving in the direotion of arrow 24. the
30 indi~idual labels 16 are cut from the web 14 so as to
leave a skeletal waste 14A whioh is taken away from the
nip for disposalq the labels 16 bein~ held to the drum
10 by 'che applicatlon of a vacuum to ports 26 ln the
cylindrlcal surfa~e thereof to which the labels 16 are
35 he~dO When the labels 16 are so. held to drum 10. the
adhesive surfaces are outermost enablin~ the labels to
be applied directly to articles which ~ove into clo~e
~2l3Z43~3
proxi~ity with the surface of the drum 10 at an
application location (region A in Fig. 1) so that the
labels 16 oan be transferred from the drum to the
articles. The eDtire prooess is a s~ontinuous process
05 in tha'c the web-14 is fed continuously and the drums 10.
and 12 are adhered continuously. thereby achieving high
speeds although a step by step arran~ément can also be
utilisedO
lO The running of such machinery at high speeds as can be
appreciated brings problems of effici.ently separating
the labels 16 from the vacuu~ drum 1(~ and the Present
invention provides a method for aohiellin~ the reliable
separation of the labels from t~e vacuum drum. This
15 i5 achieved in the ~ollowing manner. It will be
roticed that the ports 26 are arranged in row~ 26A. 26B
.. . . .. .. .. . . .. ... . . . . . . . . . . . . . . ..
~r)d 50 ~r~. extending axially of t~e periphery of ~he
drum 10 and arranged in parallel rela'..ionship. and the
vacuum is applied to these ports ~hrough vacuum lines
20 30 in a vacuum valve blook 32 which remains stationary
as drum 10 rotates. The vacuum l~l applied to the
ports 26 between the location of ~he nip and th0
separation location A ~o that the labels 16 will be
held to the drum 10 as shown. but when the leadin~ edge
16A o~ each label 16 reaches the location A~ the
'leading ports s~ch as 26A and Z6~ are supplied. instead
o~ with vacuum. with air un-der pressure in order to
blow the leading edge 16A away fro~ the surface of the
drum 10~ and as ~he further rows of ports 26C pass the
30 release station A. so ~uch rows of ports pro~ressively
are supplied with air under pres~ure in order thak
there will be a continuous blowing of the label 16A
away from the drum surface throughout the arcuate
extent to which the label 16 over}aps the drum 10.
In accordance w~th the present invention however. the
~equence of blowing is controlled so as to give
positive displacelDen'c of the leadin~ edge 16A of the
label away fro~ the drum surface. and this can best be
explained by referring to Figso 2~ 3 and 4.
05 In ~ieO 2 it is seen that the ports 26A are suPplied
from an inlet 34 lying relatively close to the
periphery of drum ~0. and ports 26C to 26N are supplied
by inlet~ 36 which are on the same patch circle as port
340 However~ ports 26B l,e. the second row of ports
lO are suppl~ed from an inlet 38 which is loaated on a
smaller pitch circle than ~he ports ~4 and this i5 to
provide tbat air under pressure will be supplied to the
ports 26B in faot fraotionally before i~ is ~upplied to
the ports 26A when l~he leading edge 1fiA of 'che label ~6
15 is ~o be removed ~roo~ ~he dru~. The mek~od o~
achieYing th~s oan also be understo~d from Fig. 2 in
$ah~ch the under ide of the lJalYe blook ~2 ls shown. and
it will be ~e0n that there is a firs~ air pre~sure port
40 and a second air pressure port 42 these also belng
20 shown ln Fig. 10 por'c 40 lying on a pitoh oircle of 'che
blook ~2 which registers with tl.ie pitch circle
containing the inlets 34 and 36 in the drum 10. whilst
port 42 lies on a~pitch oircle which r~glsters with the
pitch ~ircle ~ontaining inlet 38 in drum 10. On the
25 undersurface of the valve bl~ck 32 there is a gallery
41l leading fro~ port 42 and extendin~ circumferen'cially
of blook 32. This gallery ~4 ls arranged to register
with khe inlet 38 before port ~ r~aister~ with inlet
34 when the valve block ~2 and drum 10 are
30 operationally arranRed as shown in Flg. 2.
.
As a result. when tbe machine operates. the pres~ure
air supplled through inlet port 42 in the valve blook
will be supplied to the inle'c 38 and ports 26B before
35 air under pre~sure is supplied throu~h Port 40 to inlet
~4 and even'cually to ports 26A. FurtherlDore. the
pressure of air ~upplied to the port~ 2S~ is from a
~;
~2~3Z438
g
regulated source and will be lower than that supplied
to the ports 26A.
Figs. ~ and 4 show what happens as the gallery ~4
05 registers with inlet 30h and when port 40 registers
with inlet 34.
In Fig. 3. which shows in cross sectional plan leadin~
edge 16A of the label lying on the drum 10 at the
I0 detachment location A~ and tbe gallery 44 has
registered with port 38 and has supplied air under
pressure through ports 26~. The leadin~ edge t6~ ~f
the label 16 has llfted from the surface of the drum 10
but only to a very s~all extentO for examPle of. ~he
l~ order of 1 mm. and would remain in this condition were
it not for the subsequent application of higher
.. ..... . .. .. . .. . . .. . .. .. . . .. .. ... . .. . . . . .. . .. . . ... . .. . .. .
pressure air blast through the inlet 34~ and th~ 5 i~
achieved when the port 40 registers with inlet 34 to
provide the condition ~hown in Fig. ~. The high
20 pressure air blast indicated by arrow 4B in Fig. 4 in
is~uing through port~ 26A ca~ses the leading edge
portion 16B in fact to hinge sharPly away ~rom the
surface of the drum 10 as ~hown in Fi8. 4. enabling for
example the insertion of a mechanlca~. par1ng knife 50
25 in~o a location between the label leading edge 16A and
,the surface of the drum 10. Continued rotation of the
drum 10 ~eans ~hat the subsequent lnlets ~6 are appl~ed
in turn with air under pressure pro~ressively to detach
the label 16 from the drum surface.
The system as de~or~bed works excellently under test.
oonditions~ and will provide a means whereby the labels
oan be detached positively and effectively and at hiBh
speed so that they can be applied reliably to the
35 articles which move in synchronism therewith.
