|Title of Invention||
"A CROWN CLOSURE"
|Abstract||A crown closure comprising a top portion, a cylindrical wall portion extending downwardly from said top portion characterized by defining a fluted skirt or a flange, and a sealing member/liner provided at the inner periphery of said top potion wherein the angle between said flange and the base thereof is not more than 12° and said flange is formed from said cylindrical wall at a radius not more than 1 mm.|
|Full Text||The present invention relates to an improved crown for use in covering beverage
In the beverage industry one of the most important aspects has been the need for crowns. A conventional crown is made of tinplate shell and a plastic liner to form a seal between the shell and the bottle mouth. A tin plate shell suffers from the draw back of rusting. This problem is overcome by aluminium crowns. The previous attempts to make crowns from a harder alloy of aluminium failed as the top portion used to separate from the body of the crown. Furthermore, the prior art crowns used to pop off from bottles during transportation and handling. It also at times used to pop off while storage-posing a serious safety threat to the consumers. In addition, the prior art crowns showed very little to no deformation on opening and thus could be re-applied, offering poor tamper evidence. While aluminium crowns show better tamper evidence, steel crowns also provide equally good tamper evidence.
The manufacture of beverages can be basically divided into the following stages - manufacture of the concentrate or syrup; manufacture of the liquid beverage; bottling; carbonation and finally delivery to the retailer. Of these stages, the stage of bottling is very important since the liquid beverage should not lose its carbonation content before sale to the consumer. The bottled beverage should also be tamper proof.
In the prior art emphasis has always been on steel - tinplate crowns because of their resistance to damage. However, steel crowns suffer from the defect of rusting. Under the peculiarly high humid conditions prevailing in most tropical countries like India, the steel crowns used could leave rust marks on the bottle. Moreover, the crowning process using conventional steel crowns requires stoppage of the plant for equipment maintenance at regular intervals and thus renders the entire process more expensive.
A search was on to discover new metal alloys which could help avoid the abovementioned problems. During the early 1960's aluminium was tested to manufacture such crowns. Such prior art aluminium crowns has a 26 mm
crown with a cut-out center panel tab attached to the skirt by two lanced or
scared grooves. A tinplate steel disk was inserted and adhered to the aluminium shell by the molded PVC liner which overlapped the disk and the corner radius. In use during the crowning process, the crown was handled conventionally. However, special presser foot assemblies and crowning throats were required. Such crowns were only used for beer. Crowned bottles had to be necessarily packed in full cartons with overlapping covers to protect the protruding raised tab. A major disadvantage of such crowns was crown fractures during shipping.
This invention relates to an intermediate crown. This crown can have a height of 5.97 mm. These crowns are made from aluminum alloy and comprise a circular cap body, a flat top portion and a crimped portion formed about the circumference of the said body extending downwardly suitable for sealing glass
An objective of the present invention is to provide an aluminium crown which effectively seals the bottles and retains carbonation content. Another objective of the present invention is to provide a crown which does not fracture and also provides tamper evidence so as to maintain product
The crown closure of the present invention comprises a top portion and a cylindrical wall portion extending downwardly from said top portion in the form of a plurality of corrugations to define a fluted skirt or a flange and a sealing member or a liner provided at the periphery of said top portion wherein the angle between said flange and base thereof is not more than 12° and said flange is formed from said cylindrical wall at a radius not more than 1 mm.
It is also provided with a dry blend double ring profile of a molded liner for sealing purposes. In order to increase the locking area of the closure, the corner of the crown has been flattened between the parallel wall and the fluted skirt. This prevents the crown to pop off from the bottles during handling or transportation.
The outer portion of the crown known as the skirt forms an angle a with the
base. This angle can be about 12 degrees or less and provides effective sealing
between the crown and the neck of the bottle. As a result of reduction of this angle as compared to the conventional crowns, the tightly crimped crowns of the present invention cannot be easily removed from the bottle without deforming them. It also makes it impossible to re-apply the crown on to the bottle. A comparative chart of the features of conventional steel crown and the aluminium crown of the present invention is quoted:-
The crown closure of the present invention comprises a substantially flat top portion and a cylindrical wall portion extending downwardly from said top portion in the form of a plurality of corrugation to define a fluted skirt or a flange. A sealing member or a liner provided at the periphery of said top portion. The angle oc formed between the flange and the base thertof is not more than 12°. This flange is formed from the cylindrical wall at a radius not exceeding 1 mm.
A liner which can be ring shaped weighing not less than 170 miligrams rests against said top inside portion of the crown. This liner can be provided with a
circumferential wedge or a groove so that all the three., surf aces of the bottle mouth can be sealed.
More preferably the angle between the flange and the base is not more than 10° and the radius is not more than 0.75 mm.
Since users require crown closures that can be used on existing crown application machines, the overall dimensions such as height and outer diameter have not been altered. This is because intensive research has shown that it is not essential for the functioning of the improved crown to be different in all its parameters from the known crowns for closing a container.
Accordingly, the present invention relates to a crown closure comprising a top portion, a cylindrical wall portion extending downwardly from said top portion characterized by defining a fluted skirt or a flange, and a sealing number/liner provided at the inner periphery of said top potion wherein the angle between said flange and the base thereof is not more than 12° and said flange is formed from said cylindrical wall at a radius not more than 1 mm.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention will now be described in greater detail for better understanding with reference to the accompanying drawings: -
Figure 1 represents a sectional view of a crown of the present invention; Figure 2 represents a partial sectional view of the liner profile for sealing;
In Figure 1, the crown body or shell (8) having a top portion with a fluted skirt (3). This skirt can be provided with at least 21 corrugations or more around the circumference of the crown. However, the skirt of the crown is provided with a flat shape and a flange angle (a) of 12 degrees or less. The thickness of the shell is represented by 1 in the drawings shown in Fig 1. This can be 0.30 mm. The radius (2) formed by the parallel wall of the crown and the flange (3) is not more than. 1 mm. This enables the crown to be provided with a somewhat flatter look.
The top portion of the crown can be domed to a radius of curvature (5) in the range of from 139.7 mm to 203.2 mm. Its height can be of from 5.97 mm to ±0. ] 0 mm and an overall diameter of 32.05 mm ± 0.2 mm. The inside diameter of said crown can be of from 26.80 mm + 0.08 mm inside parallel wall (6) and the top radius of the corner between the top flat portion and the parallel wall does not exceed 1 mm.
A double ring shaped dry blend molded liner 4 can be provided in the top flat poilion. This can be adhered to the flat inside portion. This liner can be made of polymeric material such as PVC and the like.
Every crown has a liner which brings distinct benefits. The liner consistency enables it to withstand internal pressure upto 180 psi. Uniform liner profile from crown to crown ensures smoother performance in filing and sealing lines. Closer cell structure guarantees greater resistance to liner permeability. Seals close to the liner lip radius are reliable for recycled bottles. The liner has greater resilience during transportation and can withstand warehouse stresses.
It has been found after extensive research that when flange angle (a) with respect to the base is preferably of 10° and the radius of the flange is 0.75 mm, the force applied to crimp the crown on to the neck of the container increases and the crown gripping is tremendously improved.
In Figure 2 is shown the cross section of a liner profile (2) over the glass bottle lip to create a inner, top and some outside seal on the glass bottle (3). This profile is such that it covers surfaces of a container such as a beverage bottle. When glass surface comes in contact with the liner surface a distinctive seal is provided to the container.
The crown is made of aluminium alloy and is rust-proof. The cut-edge remains unaffected even in prolonged humid conditions. Being rust-proof, the crown of the invention does not form rust rings on the bottle.
Crowns are very much lighter than tinplate crowns. As a result, storage and handling of these crowns in cartons is easier. Since aluminum is a softer alloy than tinplate, the crowns are easier to open. The softness of the alloy also reduces wear and tear of the crowning head and prolongs ii..s operating life. Due to the softness of the cut-edge of the crown the eventual decoration and internal lacquer remain unaffected during hoppering.
The process comprises the stages of trimming, crown decorations, punching and lining.
Base metal received in form of coils is first cut in the form of rectangular sheets. If received in form of sheets, they need to be trimmed to size. The crown punching press are sheet fed, requiring very close tolerance of ± 0.30 mm along the direction of feeding for accurate punching and centering of the printed matter. The size of the sheet depends upon the type of punching press used.
The underside of the trimmed sheets has to be coated, lacquered on the top, printed over the lacquer and varnished on the top of the print to protect it. The sheets need to be baked in an oven after each operation of coating / printing. The baking in the oven hardens the lacquer, lithography and the varnish and make them resistant to scratches. The sequence of decoration is as under :
A. Washing: The trimmed aluminium sheets are washed to remove oil from the
sheet using mineral spirits. The sheets are passed through the roller coating
and the spirit is evaporated by passing through the oven at 195 degrees
B. External Coating : The washed sheet is externally coated with Vinyl size,
film weight of 0. 1 5 - 0.20 milligrams per square inch, baked at a temperature
of 180 degrees Celsius. The lacquer serves as an interface between the base
metal and printing inks.
C. Internal Coating : The externally coated sheets are then internally coated
with Vinyl size, film weight of 0.15 - 0.20 milligrams per square inch, baked at a
temperature of 180 degrees Celsius. The lacquer serves as an interface between
the base metal and further coatings.
D. Internal Coating : The internally sized sheets are then again internally
coated with Organasol , film weight of 0.60 - 0.80 milligrams per square inch,
baked at a temperature of 200 degrees Celsius. The Organasol acts as a glue for
the liner to adhere to the crown shell.
E. Printing : Coated sheets are printed as per approved designs and color with
heavy metal free organic inks using offset-lithography process. The number of
times this step is repeated would depend on the number of colors to be printed as one color is printed each time. The inks are cured in the oven at 160 degree
F. External Coating : The print on the sheets is protected by a coating on top of
the print to prevent it from scratching and also provide a good flow of the
crowns from the hopper to the chute. The print is coated with Epoxy ester
varnish film having a weight of 0.80 - 1.0 milligrams per square inch, baked at
a temperature of 160 degrees Celsius.
G. Internal Coating : The externally varnished sheets are then again internally
coated with a Vinyl Lacquer film having weight of 0.40 - 0.60 milligrams per
square inch, baked at a temperature of 160 degrees Celsius. The lacquer
improves the adhesion of the liner to the crown shell. It also makes up for any
patches formed of the varnish on the internal surface of the sheets from the
The internally coated, lacquered, printed and varnished sheets are then punched to form crown shells. Pallet of sheets are loaded on the automatic feeder of the press. Press are double acting, equipped with precise forming dies to obtain metal shells.
The sheets while feeding are lubricated with wax which considerably reduces scratching during the mechanical punching of sheets.
Crown shells through transfer equipment are either stored in a storage bin or led into the hopper of lining machine. The crowns travel through the chutes, pass through the induction heated turrets. Lining material in form of granulate is fed into the extruder, heated to pre-set temperature. Extruded compound is cut into pellets of predetermined weight and deposited in the pre heated shells.
The crown further travels to forming station, high pressure molding punch presses the softened mass of compound onto the shell to give it the required profile. The machines are generally fitted with vacuum inspection for liner
These crowns offer total resistance to rusting. They do not rust, thus leaving no rust ring marks on the glass bottles. These crowns offer better tamper evidence. Being softer, these crowns get damaged/dented upon opening, therefore, more evidence of tampering. Material being softer, maintenance of crowners in bottling plants get reduced.
1. A crown closure (8) comprising a top portion, a cylindrical wall portion extending downwardly from said top portion characterized by defining a fluted skirt (3) or a flange, and a sealing member/liner provided at the inner periphery of said top potion wherein the angle between said flange and the base thereof is not more than 12° and said flange is formed from said cylindrical wall at a radius not more than 1 mm.
2. A crown closure as claimed in claim 1 wherein said angle is 10° .
3. A crown closure as claimed in claim 1 or 2 wherein said radius
is not more than 0.75 mm
4. A crown closure as claimed in any of the preceding claims 1 to 3
wherein said member/liner is provided with a circumferential
wedge/groove profile matching with the mouth of the
bottle/container to be sealed/ closed.
5. A crown closure as claimed in any of the preceding claims 1 to 4
wherein said closure is made of aluminum or aluminum alloy.
6. A crown closure substantially as herein described with reference
to the accompanying drawings.
|Indian Patent Application Number||1843/DEL/1998|
|PG Journal Number||13/2009|
|Date of Filing||30-Jun-1998|
|Name of Patentee||THE COCA-COLA COMPANY|
|Applicant Address||ONE COCA-COLA PLAZA, ATLANTA, GEORGIA 30301, U.S.A.|
|PCT International Classification Number||B65D 41/12|
|PCT International Application Number||N/A|
|PCT International Filing date|