Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~8Z3~1
In the course of time, returnable bottles are rendered un-
attractive by scratches around the upper and lower edges of the cylindrical body
of the bottle. Bottlers, to whom the appearance of a bottle is of great import-
ance, segregate such bottles although they are other~ise perfectly satisfactory.
It is known to provide bottles with a coating of synthetic
material, both for protection and for decorative purposes. The coating is in-
tended to protect the glass from being scratched and to prevent the walls of
the container from being weakened by scratching. The coating is furthermore
to ~e such as ~ill withstand stresses arising from repeated re-use of the
bottles. It is true that in this case the bottle itself is protected, but not
the coating of synthetic material. Frequent re-use of the bottles renders the
coating unsightly.
In order to extend the life of the bottle and retain its
pleasing exterior, a special design of bottle has been proposed having a narrow,
prajecting impact collar at the top and bottom of the cylindrical part thereof.
Although these collars become scratched in use, the scratches, being confined
to t~o narro~ strips, do not render the bottle as unsightly as scratches dis-
tributed over a large, unconfined area of the smooth surface of the bottle.
It is also known to apply soluble or decomposable coatings of
synthetic materials to bottles by printing in a conventional cleaning lye. Such
coatings are intended to be decorative and to replace labelling with printed
foil or paper labels.
It is the purpose of the present invention to provide a way of
achieving a longer life for bottles in danger of being scratched.
According to the invention, this purpose is achieved ~ith a
method for repairing surface-damaged glass containers, more particularly scratch-
ed glass. hottles, in that the depressions and/or scratches in -the surface-
--1--
~23~
damaged area are filled ~ith a synthetic material which penetrates thereinto asa result of its lo~ surface--tension. This filling is preferably carried out in
such a manner that at least the surface-damaged areas are covered with a thin
~up ~o 10 ~) film of synthetic material.
~ hereas in the case of known methods, the glass container has
been protected from scratches by the coating of synthetic material, the invention
follows a totally different path, in ~hat it accepts the scratches, but elimin-
ates them ~ith a thin coating of synthetic material, thus restoring the pleasing
exterior of the bottle. Since it is not intended to protect the bottle from
scratches, but only to render the scratches invisible, the coating needed is
relatively very thin. Nor is there any need for the synth tic material to be
highly scratch-resistant, since the coating will preferably be renewed at each
re-use. Although the ~ottle will normally be completely re-co~ted, local
coating of areas su~jected to scratching is sufficient.
The dura~ility of ~he film of synthetic material applied to the
bottle may be improved by applying the said film in a ~aterproof thickness. This
reduces the danger of premature detachmen-t at the edges.
~ la~ever, since the film of synthetic material is porous, water
may cause detachment over practically the whole surface. The danger of detach-
nlent can in this case be reduced, of course, by using a suitably adhesivesynthetic material.
According to another development of the invention, the synthe-
tic material used cannot be detached in water, but is soluble, detachable or
decomposable in a cleaning lye. In this case the film is removed simultaneously
~ith the cleaning of the container, which is necessary in any event.
Satisfactory results have been obtained with a synthetic
material ~hich hardens under ultra-violet radiation
--2--
~Z3~
In order to prevent the surface of the container from being
rendered unsightly by handling after the synthetic material has been applied,
the material used is preferably resistant to mechanical stresses such as impact
and scratching. Ho~ever, as already indicated, the demands to be met need not
be particularl~ high since the coating will preferably be renewed each time the
bottle is recycled.
5ince the synthetic material will not, as a rule, be required
to alter the appearance of the bottle, but only to render the scratches in-
vi~ible, the material used ~ill be colourless or of the same colour as the con-
tainer.
The coating of synthetic material may be applied in various
uay~, for example by sublimation with a gaseous synthetic material condensing
on the container, by spraying or rolling a liquid synthetic onto the container,
by imm~xsing the container in a bath of liquid synthetic, or by pouring the
synthetic over the container. Synthetic material in the form of a paste may
also be applied by rolling or paintir.g.
Prior to the application of the synthetic material, the bottle
Will be cleaned and dried, preferably under heat, so that the material may be
applied to the ~hole surface, and ~ill be smooth and free from bubbles.
If the required thickness of syn~hetic material coating is not
o~tained upon application, it may be adjusted by draining, blo~ing, doctoring
or ~craping. After the coating has been applied and adjusted for thickness, it
is preferably dried, more particularly by ultra-violet radiation.
An apparatus for carrying out the method is characterized by
conveyor means ~hich move the containers individually through a plurality of
consecutive treatment sections, the first comprising means for drying the sur-
face of the bottle and the second a mechanism for applying the coating of synthe-
--3--
2~
tic material. This second section may be follo~ed by a section comprising means
for drying and hardening the coating.
The drying means in the first section is preferably in the form
of air-nozzles. In order to eliminate any moisture remaining on the surface of
the bottle to be coated, provision is made, according to one configuration of
the apparatus, for heated rollers to be arranged at the end of the section, uponwhich the cylindrical containers roll.
~et container~ may be pre-dried particularly effectively by
means of wipers applied to the surfaces thereof. This pre-drying is preferably
carried out prior to the blo~-drying with air. Ths wipers are preferably leaf-
shaped and are applied to the surface of the container in parallel with the axisof the c~lindrical container. Associated ~ith the containers is a drive which
causes them to rotate about their own axes so that the whole surface i5 covered
hy ~he ~ipers. The ~ipers and air nozzles may be arranged upon an inlet spider
and may rotate there~ith.
The conveying means~ in the first treatment section may be in
the form of conveyor worms followed by an inlet spider. A turntable ( a rotat-
ing table ~ith pick-up locations for the containers at is periphery) may be
used as a conveying means for the second treatment section.
In order that the containers may be coated on the move, ~he
application mechanism is synchronized ~ith the movement of the containers, and
may consist of a plurality of spray heads. In order to be able to apply the
coating to the surface of the containers, each spray head comprises nozzles
known per se ~hich can be pulsed on and off, the said nozzles being triggered
individuall~ or in groups (Siemens ~eitschrift, 51st Year, Volume 4, April 77,
pages 219-221). Each spray head may be in the form of a bar extending over the
height of the container to be coated, a drive, more particularly a rotary head
--4--
or plate, being associated with the container and causing it to rotate about its
o~n axis, as a result of which the whole surface is coated. The spray head may
also be in the form of a ring adapted to travel over the height of the container
to ~e coated.
Instead of being sprayed, the synthetic material m~y ba rclled or
pressed on. In this case, the application mechanism consists of a belt extend-
ing along the treatment section. However, it is aiso possible to design the
said application mechanism in the form of a labelling station, with moving
rollers or segments applying the synthetic material to the containers.
The drying means arranged in the third section are preferably
radiators, more particularly ultra-violet radiators.
The combination with a labelling machine is particularly satis-
factory. In this case, no additional conve~ing means need be provided. Existing
conveying means, especially thc turntable, convey the bottles to the labelling
machine.
The invention is explained hereinafter in greater detail in
conjunction ~ith the drawings attached hereto, l~herein:
Figure 1 is a diagrammatical plan vie~Y of an apparatus for
repairing glass bottles;
Figure 2 is a plan view of an inlet spider;
~igure 3 is an axial section through the inlet spider according
to ~igure 2;
~igures 4 to 7 sho~s various designs of applicatlon mechanism;
and
Figure 8,on the same sheet as Figure 4, shows a drying and
~ardening unit.
A row of bottles 1, to be repaired, is fed on a plate conveyor
--5--
23~
belt 2 to a first treatment section. In the first part of this section, the
feed means is in the form of a conveyor worm 3 which spaces the bottles apart.
The feed means in the second part of the first treatment section is in the form
of an inlet spider 4 followed by a turntable 5, i.e. a rotating table having a
plurality of bottle pick-up locations. The bottles leave the unit on an outlet
spider 6 followed by a plate conveyor belt 7.
The basic design of this apparatus is known from bottling
unitS. It is also known from these units that the bottles may stand upon turn-
tables and may be gripped by heads which cause them to rotate about their own
axes. This known design renders a detailed description unnecessary, especially
since it i5 not essential to the method and apparatus according to the invention.
In the embodiment illustrated in Figure 1, a blowing box 8, 9
is arranged on each side of the conveyor section, from which air is blown from
nozzles lQ,ll onto the bottles to be dried, after which the said bottles pass
to inlet spider ~. The latter comprises a pluralitr or rotatable, heated rol-
lers 12 ~Yith yielding surfaces upon which the bottles roll, supported externally
b~ a guide 13. The bottles are thus heated and any residual moisture is removed
from the surfaces thereof. This heating also ensures that no moisture condenses
on the surfaces of the bottles before the synthetic material is applied.
Turntable 5 is arranged under a hood 14 to which air is
supplied from blowing box 8. Volatile solvents from the synthetic coating
n~terial leave the hood~ with the air supplied, through an outlet 15.
Means other than blowing boxes 8,9 and air nozzles 10,11 may
be used for drying wet bottles. In t'ne embodiment according to Figures 2 and 3,a special inlet spider ~a is provided and comprises lower and upper pairs of
supporting rollers 16,17 for the bottles. The said rollers pressing the bottles
against an outer guide 18. As the spider rotates, the bottles rotate abou~
--6--
23~
their o~n axes. Associated ~ith each bottle pick-up location is a leaf-shaped
~iper 19 which wipes the liquid from the surface of the bottle. The bottles
thus predried then pass into the range of air nozzles 20 which complete the
drying operation. The said nozzles may be supplied with hot air to heat the
bottles. This produces the same effect as heated rollers 12 mentioned herein-
before.
After leaving the inlet spider, the bottles pass to second
treatment section 21 equipped ~ith the application mechanism illustrated in
Figures 4-7.
The mechanism according to Figure ~ comprises a plurality of
flat spra~-heads 23 circulating on a closed track 22 along the path of travel
o~ the bottles. The said spray-heads are synchronized with the movement of the
bottle pick-up locations. Bottles 1, caused to rotate about their o~n axis by
a turnta~le 26, kno~n per se, remain ~ithin the range of the spray-heads until
each ~ottle has rotated through 360. Thq spra~-heads are connected, through
a line 24 to a common supply 25 of synthetic material.
The application mechanism according to Figure 5 differs from
that sho~n in Figure 4 in the matter of the spray-heads. Spray-heads 27 in
Figure 5 are annular and are moved over the height of the bottles by a lifting
c~linder 2~. As in the design according to Figure 4, the spray~heads may
circulate on a closed stationary track, moving with the bottles along a part of
their path of travel. It is also possible, ho~ever, to provide each bottle
pick-up location with a spray-head. With annular spray-heads, there is no need
for tKe bottles to rotate about their o~n axes.
In the design according to Figure 6, the application mechanism
consists of a resilient belt 31 running over rollers 29,30, with the bottles 1
rolling on the said belt. As in the case of the gluing rollers in labelling
--7--
~23~
machines, the synthetic material is applied to belt 31 by an applicator-roller
32, the thickness of the coating being adjusted by scraper 33.
The design of the application mechanism according to Figure 7
~orresponds largely to that of a labe~ g machine. Applicators 34, having
curved surfaces are mounted to rotate or oscillate in a ro-tating carrier 35,
and they roll on a roller 36 which is supplied ~ith synthatic material after
the manner of a gluing roller. The said applicators, With their surfaces thus
coated with synthetic material, then roll on bo-ttles 1, which rotate about their
o~n axes, thus coating the said bottles. As is known from labelling machines,
the whole surface of the bottle may be coated, with or withou~ relative move-
ment bet~een the bottle and the surface of the applicator, by means of a non-
uniform drive, appropriate curvature of the coated surface of the applicator,
and an appropriate mounting. This produces a coating of uniform thickness.
The bottle, coated by one or the other of these mechanisms,
then passes to third treatment section 37 on each side of which are arranged
radiators 38 (Figure 8~, preferably ultra-violet radiators, for the purpose of
dr~ing and hardening the coating of synthetic material. The length of this
section depends upon the period of residence needed for drying.
As shown in Figure 1, turntable 5 also has a final treatment-
section 39, in ~hich one or more conventional labelling machines 40 may bearranged.