FIELD OF THE INVENTION:

The present invention generally relates to a dipping apparatus for producing latex article, and more particularly relates to an automatic dipping apparatus integrated with an online powder finishing and vulcanizing operation for producing male condoms.

BACKGROUND OF THE INVENTION:

Current practice of production of condoms facilitates straight line dipping method and the condom formers are made from glass. The formers are fixed to an endless chain, where the formers are able to turn and swivel. The chain conveyor travels through a single loop and a lower chain progressing through different stages (cleaning, dipping and vulcanising). While an upper loop travels through drying ovens, a beading brush, and a leaching tank before the condoms are stripped by underwater stripping. The ovens are heated by electric heaters. The movement of the formers is achieved by contoured guides along the line. The whole chain is driven by an electric motor with a frequency inverter to control the speed of the chain. All the wet condoms collected are then mixed in powder-slurry water before drying in a tumbling dryer.

In existing system, complete drain of latex is not obtained during maintenance that leads to wastage of latex 5 Kg and also requires more than one person to be engaged for cleaning purpose alone. The material used for the conveyor chain is carbon and is soft in nature that contributes frequent wear and tear. Hence, the frequency of replacement is increased. The existing system also needs manual intervention for powder finishing operation and collection of products. Further, in human health care products/service defects are crucial and retard achieving industrial bench marks. Therefore, there arises a salient need for a system that overcomes the above limitations and initially, few systems have been proposed.

PCT publication number 2008097643 to Wei cheong Wong et al. entitled "glove coating and manufacturing process" relates to a coating composition for skin-contacting surfaces of medical and laboratory gloves. A condom manufacturing process in which formers are dipped into latex and dried using hot air oven during molding operation. The cured gloves are

leached in hot water to extract more water soluble materials and dipped into slurry of calcium carbonate powder or starch powder. The gloves are dried using water extraction machine and cyclone drier. The nylon brushes are used for mechanical brushing during cleaning.

Chinese document number 1035429 to tianming yu et al entitled "Single-Machine Productive Technology for Immersion and Electric Test of Condom" relates to a production equipment for latex condom technology. The molding operation includes dipping formers dipped into latex and drying after a first dip. A curing dryer is used for drying and a main chain belt is made up of stainless steel.

United States patent number 8673993 to Armin Holzner et al. entitled "Method for producing a cross-linked elastomer" relates to a method for producing a cross linked elastomer, wherein the crosslinking is performed in at least two stages as pre-crosslinking and post-cross linking. In this method, mold is immersed into an immersion bath and dried after immersion during the molding operation. In powder finishing process, a drying unit and a conveying device are used.

United States patent number 2399319 to Peterson Dewey A et al. entitled "dipping machine" relates to forming of rubber articles by dipping processes. A condom dipping machine is provided with an individual control device for each dipping tank and a drying chamber for drying. A conveyor is used for movement of mould.

PCT publication number 2009092083 to William Doyle et al entitled "Natural rubber latex having reduced allergenicity and method of making" relates to a natural rubber latex composition having reduced allergenicity. Hevea NRL condoms are produced on highly automated production lines. It involves dipping formers into latex and drying after first dip during molding operation. In powder finishing process, condoms are dried after leaching.

PCT publication number 2009061311 to William L Howe et al entitled "Methods and compositions for reducing the protein content and odor of latex articles" relates to a method and composition for reducing the protein content and/or undesirable odor of latex articles. The molds are fixed to robotic Diplomat™ 3 axis condom dipping system. The dipping tanks uses a thermostat for temperature variation and dried using oven. In powder finishing process, a convection oven and tumble dryers are used.

United States patent number 4349026 to Teruo Miyata entitled "Regenerated fiber collagen condom and method of preparation" relates to a method of preparation of novel collagen condom. In this method, mandrel is dipped into acidic collagen dispersion and dried after first dip during molding operation. In powder finishing process, product is dried after final dipping.

United states application number 20050127578 to Thomas Triebes et al. entitled "Method of making fiber reinforced elastomeric articles" relates to a method of manufacturing elastomeric articles having polymer fibers incorporated therein. The molding operation involves dipping the former into a polymer bath and then dried. In powder finishing process, curing station/tumbling apparatus/dryer is used.

Existing system available in the prior art discloses about automatic condom forming apparatus. Further the changeover time required for former changing is a time consumption process. Most of the system also needs manual intervention for powder finishing and vulcanizing process. Therefore, the present invention provides an automatic condom forming apparatus integrated with on line powder finishing apparatus and vulcanizing operation without manual intervention. The system uses press fit formers that reduces the time needed for change over of former, dipping tanks with suitable drain valves to avoid wastage of latex and water exposed system are made from stainless steel including former holder housing that reduces the frequency of replacement.

SUMMARY OF THE INVENTION:

The object of the invention is to provide an apparatus and method for automatic production of condom integrated with on line automatic powder finishing and vulcanizing operation.

The apparatus of the present invention includes a molding unit and a powder finishing operation unit. The molding unit includes a dipping line, a first latex dipping tank, a first intermediate oven, a second latex dipping tank, second drying chamber, bottom oven, a beading station, a top drying chamber, a leaching tank and a cleaning system. The powder finishing unit includes a wet tumbler/stripping tumbler unit, a powder finishing tumbler, a dehydrator and a tumbler for vulcanizing.

The molding unit is provided with a dipping line/conveyor chain having a press fit former holder. The dipping lines dip into the first latex dipping tank. Then the thin film is passed through a first intermediate oven and dried with hot air. After the second dip into the second latex dipping tank and short drying period, a bead is formed at a beading station. Then the formers are passed through the bottom oven and the top drying chamber. The formers are then led through the temperature controlled leach tank. Hot water and ammonia loosens and swells the latex films for easy stripping. The stripping is provided with slurry of Tri Sodium Phosphate.

Further, the stripped condom from the molding unit enters into powder finishing unit and is collected in the wet tumbler. The stripped condom is passed through the wet tumbler and then to the powder finishing tumbler for online powder finishing operation. The powder finishing tumbler includes a conveyor screw welded in housing. The conveyor screw and housing are relatively rotatable. The powder finishing tumbler has a conical opening to supply the material into the screw such that the screw efficiently grabs and conveys the condom through the screw conveyor.

The pitch of the screw is designed so as to get proper mixing and finishing to the product. After powder finishing operation, the condom is dehydrated in the dehydrator unit. The dehydrated condom is fed to the tumbler for vulcanizing and quenching operations.

These objectives and advantages of the invention will become more evident from the following detailed description when taken in conjunction with the accompanying pictures.

DESCRIPTION OF THE DRAWING:

The objective of the present invention will now bedescribed in more detail with reference to the accompanying drawing, in which:

FIG. 1 shows a whole apparatus with a molding unit and a powder finishing unit;

FIG. 2 shows a side view of a former brushing unit;

FIG. 3 shows a side view of a stripping unit;

FIG. 4 shows a side view of an inclined former brushing unit

FIG. 5 shows a side view of a leaching tank;

FIG. 6 shows a side view of a first intermediate drying chamber and a dehumidifier unit; and

FIG. 7 shows a side view of an F-block.

REFERENCE NUMERALS:

Main drive with gear box (1)
Conveyor chain/ dipping line (2)
Top Drying chamber (3)
Bottom oven (4)
Beading unit (5)
Second latex dipping tank (6)
Blower for cooling (7)
Blower for drying (8)
First intermediate drying chamber (9)
First latex Dipping tank (10)
First nipple cleaning unit (12)
Second nipple cleaning unit (11)
Inclined brush unit (13)
Straight brush unit (14)
Stripping unit (15)
Leaching tank (16)
Stripping/wet tumbler (17)

Stripping water circulating tank (18)
Wet powdering unit (19)
Powder finishing tumbler (20)
Dehydrator (21)
Idle sprocket (22)
Main panel board (23)
Main sprocket (24)
Split plummer block (25)
Dehumidifier unit (26)
Ammonia exhaust unit (27)
Pre heater (28)
Sub dividing damper- (29)
Tumbler for vulcanizing (30)
Second drying chamber (31)
DETAILED DESCRIPTION OF THE INVENTION:

Aspects of the present invention described herein, disclose an automatic condom dipping machine for production of male condoms without manual intervention until the vulcanizing stage by incorporating online powder finishing & vulcanizing operations.

According to the present invention, the dipping machine includes a combination of two units for production of condom. One of the units is a molding unit and the other unit is a powder finishing unit. Referring to Fig.l, the molding unit includes a conveyor chain/dipping line (2), a first dipping tank (10), a first intermediate drying chamber (9), a second dipping tank (6), a second drying chamber (31), a beading unit (5), a bottom oven (4), a leaching tank (16), a cleaning system, a main drive with a gear box (1), a top drying chamber (3) and a dehumidifier unit (26).

The dipping line/conveyor chain (2) is operated automatically and chain speed is indefinitely variable. The conveyor chain (2) is structured by coupling of plurality of chain links that mesh with a main sprocket (24) and an idle sprocket (22). Split plummer block (25) provides a support for the rotating structure such as sprocket and conveyor chain (2).

The first latex dipping tank (10) and the second latex dipping tank (6) include drain valves that avoid wastages during clarification. The dehumidifier unit (26) is incorporated after the first dipping tank (10) for moisture entrapment as shown in Fig.6. Cooling system in the dipping tanks (6, 10) are designed with an oil immersed jacket coding. Chilled water forced circulation is incorporated for cost effective cooling. Former holder used is a type of press fit former holder and corrosion free former is considered in design. The conveyer chain (2) is a long life heavy endless quality chain made of stainless steel (316 L).

Referring to Fig.5, the condoms are leached in the leaching tank (16) containing ammonia solution for improving swelling efficiency. The ammonia is exhausted using the ammonia exhaust unit (27). Referring to Fig.3s the stripping unit (15) is used for stripping the swelled condom.

The cleaning system includes an inclined brush unit (13) as shown in Fig.4, a straight brush unit (14) as shown in Fig.2, a first nipple cleaning unit (12) and a second nipple cleaning unit (11). The brushing unit is used for minimizing water requirements and for cleaning former from the stripping unit (15). Stripping and former cleaning system is also made from stainless steel.

Referring to Fig.l, the powder finishing unit includes a wet tumbler/stripping tumbler unit (17), a powder finishing tumbler, a dehydrator (21) and a tumbler for vulcanizing (30).

The wet tumbler/stripping tumbler (17) is provisioned for collection of products. Wet tumbling drive with a shaft mounted motorized worm gear is introduced.

The powder finishing tumbler (20) includes an externally driven internal screw conveyor. The screw mixer is a shaft less screw conveyor. Condom with powder and water in a desirable ratio is conveyed by a forward rotation of the screw. The pitch of the screw is designed so as to get the proper mixing and finishing to the condom. Inside the hollow rotating shaft, continuous screw vanes are constructed without any sharp corners and roughness. The screw conveyor has a feeder device i.e. blades, for carrying the condom through the conveyor system. The blades are curved in such a manner to draw the condom both from above and from below to guide it. The feeder device and screw are relatively rotatable in same directions.

The dehydrator (21) is integrated with a drier and a carry fan. The system is incorporated with an ejector and a sub-dividing damper (29) for the collection of products to the tumbler, thereby eliminating manual operation and customizing to suit the machine output. Dehydrator drive system consists of a shaft mounted, life lubricated maintenance free motorized parallel helical gear box. The sub-dividing damper (29) is also for diversion of conveyed condom to vulcanizing tumbler (30) once in every 45 minutes.

Vulcanizing tumbler (30) is incorporated for the automatic collection, vulcanizing and quenching operations of condom.

The process in accordance with the present invention, in which the production of male condom is facilitated by a straight latex dip method. The dipping line (2) operates automatically and the chain speed is indefinitely variable. They are dipped into the first latex dipping tank (10). The thin latex film passes through the first intermediate drying chamber (9) and dried with hot air. After the second dip in the second dipping tank (6) and a short drying period in the second drying chamber (31), the bead is formed at the beading unit (5). Formers are passed through the bottom oven (4) and the top drying chamber (3). The formers are then led through the temperature controlled leach tank (16). Hot water and ammonia loosens and swells the latex films for easy stripping. The stripping is provided with slurry of Tri Sodium Phosphate solution. The double track line in the dipping machine is integrated for obtaining maximum operational efficiency in the dipping machine. Reduction in downtime for former change over, change of latex in dipping tank etc. are considered. The movement of glass formers from a horizontal position to a vertical line forms a butterfly shape.

The condoms from the stripping unit (15) are passed through wet tumber (17) and then to the powder finishing tumbler (20) for online powder finishing process. The condoms from the wet tumbler (17) are conveyed to the screw conveyor through a funnel. Then the condom passes through the screw conveyor to complete powder finishing operation. After powder finishing operation, the condom is dehydrated in the dehydrator with air preheater (21). The dehydrated condom is fed to the tumbler (30) for vulcanizing and quenching operations.

While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.

WE CLAIM:

1. An automatic condom dipping machine for producing male condoms comprising:

i. a molding unit, wherein said molding unit comprising

a) a conveyor chain (2) having a press fit former holder, wherein speed of said conveyor chain (2) is indefinitely variable;

b) a dipping means comprises a first dipping tank(10) and a second dipping tank(6), wherein said first dipping tank (10) and said second latex dipping tank (6) include drain valves;

c) a drying means comprises a first intermediate drying chamber (9), second intermediate chamber (31),bottom oven (4) and a top drying chamber (3);

d) a cooling system of said dipping means is designed with a coil immersed jacket coding, wherein, said cooling system uses chilled water forced circulation;

e) a dehumidifier unit (26), wherein said dehumidifier unit (26) is installed after said first dipping tank (10);

f) a beading unit (5);

g) a dual leaching tank (16); and

h) a cleaning means comprising an inclined brush unit (13), a straight brush unit (14), a first nipple cleaning unit (12) and a second nipple cleaning unit en).

ii. a powder finishing unit, wherein said powder finishing unit comprising

a) a wet tumbler (17) having a drive with a shaft mounted motorized worm gear;

b) a powder finishing tumbler (20) comprising a screw conveyor and a housing; wherein said screw conveyor is welded in said housing;

c) a dehydrator (21) is integrated with a air preheater and a carry fan; and

d) A dual tumbler for vulcanizing (30).

2. An automatic condom dipping machine for producing male condoms according to claim 01, wherein said drain valves are provided to avoid wastage of latex.

3. An automatic condom dipping machine for producing male condoms according to claim 01, wherein said screw conveyor has one or more blades that are arranged symmetrically.

4. An automatic condom dipping machine for producing male condoms according to claim 03, wherein said blades are characterized in a curved manner to draw said condom from above and below to guide through said powder finishing tumbler.

5. An automatic condom dipping machine for producing male condoms according to claim 01 and 02, wherein said screw conveyor and blades relatively rotate in same direction.

6. An automatic condom dipping machine for producing male condoms according to claim 01, wherein said dehydrator (21) is incorporated with ejector and sub-dividing damper (29).

7. A method for producing male condoms using an automatic condom dipping machine, comprising the steps of:

a) forming a thin latex article by dipping a former into a first latex dipping tank (10);

b) drying said thin latex article by passing into a first intermediate drying chamber
(9);

c) dipping said dried latex article into a second latex dipping tank;

d) drying said dipped latex article in second intermediate drying chamber (31);

e) forming a bead in said latex article in a beading unit (5);

f) drying said latex article from beading unit (5) in bottom oven (4);

g) drying said dried latex article by passing through top drying chamber (3);

h) leaching said dried latex article by passing through a temperature controlled leach tank (16);

i) stripping said leached latex article with a slurry of Tri Sodium Phosphate solution;

a) collecting said stripped latex article automatically in a wet tumbler(17);

b) passing said collected latex to powder finishing tumbler (20) via a funnel, wherein said powder finishing tumbler (20) comprises a screw conveyor and blades welded in a housing;

c) mixing powder and water in a desired ratio with said collected latex article by the rotation of said screw conveyor and blades;

d) conveying of said latex article by rotation of said screw conveyor and blades;

e) dehydrating said conveyed latex article by a dehydrator (21)with air preheater; and

f) Collection of said dehydrated latex article to a vulcanizing tumbler by sub-dividing damper (29) for vulcanizing (30).