Title of Invention	PROCESS AND APPARATUS FOR COATING ARTICLES
Abstract	A process for coating articles with a coating compoition, typically a lacquer consisting of the steps of conveying the articles to be coated via a moving conveyor into an enclosed booth;spraying the articles with the pressurized coating composition in the enclosed booth via at least one spraying gun, collecting the excess coating composition:

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FORM-2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE Specification (Section 10; rule 13) PROCESS AND APPARATUS FOR COATING ARTICLES PRADEEP SHRIPAL BHALWANKAR of J-524, M.I.D.C., Bhosari, Pune 411 026, Maharashtra, India an Indian National THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED:- GRANTED 8-6-2004 This invention relates to apparatus and processes for coating articles. In particular, this invention relates to apparatus and processes for coating articles such as made of glass, natural or synhetic polymeric material, wood, metal, stone and the like with coatings for moisture , barrier, corrosion resistance, aesthetic improvement, wear resistance, impact resistance, and the like. Still particularly, this invention relates to apparatus and processes for coating articles by spraying. Still, particularly, this invention relates to a spraying apparatus such as a spraying booth or spraying enclosure for spraying a coating composition on an article. Still particularly, this invention relates to a spraying apparatus and process for coating lacquer or any other natural or synthetic polymeric based material from 5 micron upwards. The article in accordance with this invention can be coated with coating / spraying material on one or all sides or surfaces with one or all of the side or surface being permanent or peelable. The apparatus and process envisaged in accordance with this invention provides a system to enable uniform coating of a natural or synthetic polymeric material such as a lacquer on articles, which after 2 even curing will provide an article, which is either completely coated or one portion is kept uncoated for usage by the customer. In accordance with another aspect of this invention there is provided an eco-friendly and power saving apparatus which enables uniform coating of natural or synthetic polymeric material such as lacquer on articles and also provides for curing the coating by incident radiation such as with the help of ultra violet rays, infra red rays including far / short wave, infra red rays and / or micro waves / heater. In accordance with a preferred embodiment of the apparatus of this invention the apparatus can be placed either on-line or off-line with an existing system for making or forming the apparatus and the articles can be continuously fed by means of a conveyor to a spraying booth having a plurality of spraying guns, typically 2 to 4, targeting the article, being continuously conveyed through a spraying area of the spraying booth and being conveyed out therethrough to a curing area. In accordance with one feature of the invention an article alignment means is provided at the inlet port of the spraying booth to align the articles entering the spraying area or pre-aligned articles are fed to the spraying booth. The articles to be coated may be pretreated before spraying. The pretreatment may involve flaming, ionization, primer coating, cleaning, degreasing, conditioning and like processes. 3 According to this invention there is provided a process for coating articles with a coating composition, typically a lacquer consisting of the steps of conveying the articles tc) be sprayed via a moving conveyor into an enclosed booth; spraying the articles with the pressurized coating composition in the enclosed booth via at least one spraying gun , collecting the excess coating composition: at or near the base of the booth, by extracting the free coating composition in the ambient environment of the booth by suction and feeding the extracted material at or near the base of the booth; by scrapping the excess coating composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the enclosed booth; recycling the excess material collected at the base of the booth to the feed tank via a recycling line; re-circulating excess pressurized polymeric material from the at least one spraying gun to the feed tank via a re-circulating line; conveying the coated articles from the enclosed booth to a curing station for curing of the coated articles. In accordance with a preferred embodiment of the invention the articles are pretreated by selecting one or more methods of treatment from a group of treatments which include flaming , ionization, primer coating, cleaning, degreasing, conditioning and the like. 4 In accordance with one feature of the process includes aligning the articles before conveying them to the enclosed booth and the invention includes an article alignment means which is provided at the inlet port of the spraying booth to align the articles entering the spraying area or pre-aligned articles are fed to the spraying booth. Typically, the curing of the coated articles is done by incident radiation such as with the help of ultra violet rays, infra red rays including far / short wave, infra red rays and / or micro waves / heater. In accordance with another preferred embodiment of the invention the extracted free polymeric material in the ambient environment of the booth is filtered before feeding the extracted material at or near the base of the booth. Typically, the movement of the articles via the conveyor through the enclosed booth is at speeds controlled between 1 mtr. per minute to 50 meters per minute. Typically, the process involves adjusting the spraying guns to deliver high volume at low pressure coating compositions to the spraying area. Alternatively, the spraying guns can be adjusted to deliver low volume at high pressure. Typically, the coating compositions with high viscosity need pre¬heating before spraying to achieve required properties. 5 Typically, the preheating step is provided just before spraying to achieve the desired viscosity. ang^can be done In the process in accordance with this invention healing can be done by using hot water. A process for coating articles with a coating composition, typically a lacquer consisting of the steps of conveying the articles to be coated via a moving conveyor into an enclosed booth; spraying the articles with the pressurized coating composition in the enclosed booth via at least one spraying gun , collecting the excess coating composition: at or near the base of the booth, by extracting the free coating composition in the ambient environment of the booth by suction and feeding the extracted material at or near the base of the booth; by scrapping the excess coating composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the enclosed booth; recycling the excess material collected at the base of the booth to the feed tank via a recycling line; re-circulating excess pressurized coating composition from the at least one spraying gun to the feed tank via a re-circulating line; conveying the coated articles from the enclosed booth to a curing station for curing of the coated articles. 6 According to another aspect of this invention there is provided apparatus for carrying out a process for coating articles with a coating composition, typically a lacquer as claimed in any one of the preceding claims consisting of a spraying booth fitted with at least one spraying gun for spraying the coating composition on the articles to be coated; v a curing station where coated articles are led for curing; a conveyor for conveying the articles to be coated from the spraying booth to the curing station; the spraying booth defined by a recycling pot at the operative base of the booth and a coating composition mist extraction arrangement at the operative top of the booth and means to permit ingress and egress of a conveyor bearing articles to be coated; a feed tank for supplying coating composition to the spraying gun/s in the spraying booth; means for on line pressurizing the coating composition to be supplied to the spraying guns/s; feeding means for extracted feeding coating composition at or near the base of the booth; scrapping means for scrapping excess coating composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the booth; recycling means for recycling the coating composition collected at the base of the booth to the feed tank via a recycling line; re-circulating means for re-circulating excess pressurized coating composition from the at least one spraying gun to the feed tank via a re-circulating line. 7 Typically, the apparatus includes a pre treatment booth for pre treating the articles to be coated by one or more methods of treatment from a group of treatments which include flaming , ionization, primer coating, cleaning, degreasing, conditioning and the like. In accordance with a preferred embodiment of this invention the mist extraction arrangement includes a filter for filtering the coating composition mist before leading it to the base of the spraying booth. The mist extraction means may typically consist of a perforated bowl with baffles. Typically, the re-circulating line includes an online filter. Typically, the feed tank is provided with a level indication means. Typically, the recycle line includes a strainer, filter and pumps means for straining and filtering the coating composition to be recycled to the feed tank. At least one heat exchanger is provided between the feed tank for heating the coating composition for adjusting its viscosity. In accordance with a preferred embodiment of this invention, a strip heater is provided just before feeding pressurized coating composition to the spraying gun for heating the coating composition and thereby 8 adjusting the viscosity of the coating composition being fed to the spraying gun. Typically, a differential gauge controlled filtering arrangement provided between the feed tank and the spraying gun for filtering the coating composition being fed to the spraying gun. Typically, according to the filtering arrangement includes a stand by filter for diverting the coating composition in case of chocking of the filtering arrangement. A control valve for controlling the feeding of coating composition from the feed tank to the spraying gun/s may also be included. Another feature of this invention is a programmed logic controller arrangement equipped with sensors for controlling the flow, viscosity and temperature of coating composition being fed to the spraying gun/s. The apparatus of this invention incorporates equipment to avoid wastage by recycling of the synthetic or natural polymeric material such as the lacquer and usage of the recycled coating material as part of a continuous process of coating. In the conventional coating by spraying process, water curtains or dry air booth consisting of paper filter walls are used. This type of system has a high maintenance requirement and is not economical. 9 Envisaged in accordance with this invention is a Wet Booth System (controlled atmosphere in which the coating material is directly sprayed on the article and the mist is collected by using a high speed De-mister consisting of Centrifugal Mist Filtration System. From the mist collected, air and coating material such as the lacquer are separated, centrifugally. The coating material is collected and conditioned. This results in material and time saving raising efficiency to the tune of 85~92%. The present rate of wastage in conventional type of systems is about 60%. The recycling of coating material such as lacquer and on-line usage of the coating material is provided on continuous basis. Continuous (in line) usage of the recycled material & controlled atmosphere booth saves time and material. Recycling of the coating reduces pollution load released in the atmosphere during the process since the spraying composition is almost completely recycled. Again in accordance with a preferred embodiment of this invention the spraying guns are positioned in a three-dimension array placed angularly with respect to each other. Uniform coating of the article is achieved either by placing the article between the spraying guns or by conveying the article on a moving conveyor passing between the spraying guns. In the process of spraying, the article may be fixed or rotated or angularly displaced so that spraying takes place on all or desired surfaces. The guns may be stationary or displaceable and may 10 be strategically located to spray some or all of the surfaces. The spraying process is conducted without any human intervention. It is possible to coat the articles by displacing the guns or revolving the articles. Total area of the article is covered by the guns, which are positioned specifically. The production level can be optimized, since process according to this invention is continuous. In accordance with an alternative embodiment of the invention the spraying is either air assisted or airless or electro static. The movement of the articles via the conveyor is at speeds controlled between 1 mtr. per minute to 50 meters per minute. The spraying guns may be preferably adjusted to deliver high volume at low pressure coating compositions to the spraying area. Alternatively, the spraying guns can be adjusted to deliver low volume at high pressure. Various sensors including optical sensors may be provided at the entrance and exit of the spraying booth to sense the presence or absence of the article or the abutment of the articles or its proper coating to enable or disable the spraying guns. The apparatus of this invention is designed for high as well as low viscous coating materials including lacquers. Lacquers with high viscosity need pre-heating before spraying to achieve required properties. Final desirable point of heating of the material is achieved just before spraying to achieve the desired viscosity. This 11 reduces power consumption resulting in an economic system for spraying and curing. In the process in accordance with this invention heating can be done by using hot water. No solid & liquid waste is produced in the process according to this invention. The equipment ensures clean and healthy environment. User does not have to bother about the maintenance of the machine and cleaning of the surroundings due to wastage created as in the conventional method. In accordance with this invention, after spraying the coated article is led through a curing process in which, typically ultra-violet, infra-red, micro-wave, thermal convection / radiation generating sources are provided at particular angle to give direct radiation on all the sides and edges of the article. Rotation / revolving of the article or movement of the curing sources may be provided. A typical process in accordance with this invention includes the following steps: 1) Loading of articles on the conveyor 2) Pre treatment of the article, if required. 3) Spraying of coating material on predefined surfaces or faces of the articles. 4) Flashing off [i.e. removing flashes of excess coating material from the surface of the articles. 5) Curing of the sprayed surface of article. 12 6) Cooling of articles, if required 7) Unloading of the articles A typical apparatus in accordance with this invention includes the following: 1) Pre treatment booth 2) Spraying Conveyor 3) Spraying booth 4) Gun Mounting arrangement 5) Spraying system 6) Belt scrapper 7) Gun flushing arrangement (flushing system) 8) Filter-mist & process instrumentation panel 9) Flash-off Conveyor 10) Curing Oven Conveyor 11) Oven booth with cooling arrangement 12) Conveyor Drive mechanism 13) Component carrying Conveyor 14) In-line spraying material heating system 15) Spraying material re-cycle system 16) Filter system for recycling of spraying material 17) Feeding tank mounting system 18) Control Panel 19) Sensors 20) PLC 13 The invention will now be described with reference to accompanying drawing, in which : Figure 1 shows a schematic top view of the apparatus and the process of this invention; Figure 2 shows a schematic side view of the apparatus and the process of this invention; and Figure 3 is a detailed schematic view of the spraying booth showing the recycling and re-circulating arrangement. Referring to the drawings, there is disclosed an apparatus for carrying out a process for coating articles with a coating composition, typically a lacquer consisting of a spraying booth 10 fitted with at least one spraying gun [SGI, SG2, SG3] via a gun mounting arrangement 24 for spraying coating composition on articles to be coated [not shown], a curing station 20 where coated articles are led for curing, a conveyor [14, 22] for conveying the articles to be coated from the spraying booth 10 to the curing station 20. Provision is made to have flexible gun mounting with easy replacement as well as change of location. Proper care is taken for preventing vibration of gun assembly during spraying. Spraying-gun flushing system [not shown] is provided to clean the guns. In the spraying system, depending upon the size of article, number of guns are placed to take care of uniform coating of articles. Typical arrangement is two guns at side diagonally opposite each other and one at top. Conveyor drive mechanism 18 is provided for driving the conveyor. Alignment means in the form of alignment bars 16 and guides 44 are 14 provided for guiding the articles on the conveyor leading to the spraying booth. The apparatus includes a flash off conveyor 30 located between the spraying booth and the curing station for removing flashings of the coating composition from the coated articles. Properly aligned articles with proper spacing are carried on the conveyor. Provision of guides are made to locate and move the articles in a straight line to avoid jamming and misalignment of articles inside the booth. The spraying booth 10 is defined by a recycling pot 36 at the operative base of the booth and a coating composition mist extraction arrangement 28 at the operative top of the booth and means to permit ingress and egress of a conveyor bearing articles to be coated [not shown] The apparatus includes a feed tank 58 for supplying coating composition to the spraying gun/s in the spraying booth 10. The apparatus further includes means for on line pressurizing the coating composition to be supplied to the spraying guns/s. Coating composition is fed to the guns by individual double acting diaphragm pumps 68 through filters [74,76] . The pump sucks material from the feed tank 58. There is provision of heating to maintain uniform viscosity i.e. the rate of shearing strain to shearing stress of the coating composition which is a Newtonian fluid throughout the day irrespective of ambient variation. Guns are provided with re-circulation line 98 to take back excess material to the tank. The apparatus includes feeding means in the form of a duct 46 for feeding the extracted feeding coating composition at or near the base of the booth 10. 15 A scraping mechanism as well as guides are provided on the conveyor belt. The scraping mechanism is provided on the spray conveyor belt to remove excess sprayed material, which is again recycled. For this purpose there is included scrapping means [34,48] for scrapping excess composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the booth 10 into the recycling pot 36. The scraping arrangements are made to take care of wiping out of excess-sprayed material. Material of construction of the conveyor is S.S. or suitable material. Provision is made for easy belt replacement as well as proper guiding mechanism. Recycling means are also included for recycling the coating composition collected at the base of the booth to the feed tank via a recycling line 56. The recycle line 56 includes a strainer 50 , filter 54 and pump means 52 for straining and filtering the coating composition to be recycled to the feed tank. Re-circulating means are provided for re-circulating excess pressurized coating composition from the at least one spraying gun to the feed tank via a re-circulating line 98. The feed tank 58 thus receives coating composition from the virgin material inlet 60, the recycling line 56 and the re-circulating line 98. In accordance with the embodiment shown a pre treatment booth 12 is provided for pre treating the articles to be coated by one or more methods of treatment from a group of treatments which include flaming , ionization, primer coating, cleaning, degreasing, conditioning and the like. 16 Mist collector of required capacity takes care of mist generated during the actual spraying operation. The mist extraction arrangement 28 , particularly seen in figure 2 consists of a perforated bowl with baffles 42 driven by a motor 40 and includes a filter 38 for filtering the coating composition mist before leading it to the base of the spraying booth 10 and feeding the mist of the coating composition collected via a re-circulating duct to the base of the spraying booth 10 and into the recycling pot 36. Coating composition collected in the recycling pot 36 is pumped up to the feeding tank 58 via the re-circulating which line includes an online filter 54 and a strainer 50. The feed tank 58 is provided with a level indication means 62. Heat exchangers 64 with water in let 70 and water outlet 72 and heat exchanger 90 with water inlet 94 and water outlet 92 are provided between the feed tank and th spraying guns SGI, SG2, and SG3 for heating the coating composition for adjusting its viscosity. Heated coating composition is fed to the guns via a distribution manifold 66. The flow of the coating composition is pressurized by means of the pump 68, which is typically a diaphragm pump. For final adjustment of viscosity a strip heater 105 is provided just before feeding pressurized coating composition to the spraying gun for heating the coating composition and thereby adjusting the viscosity of the coating composition being fed to the spraying gun. It is to be noted that shear 17 viscosity is inversely proportional to the temperature and it is critical that the temperature be maintained in a narrow range of 55 to 70 degrees Celsius. The apparatus includes a differential gauge 78 controlled filtering arrangement consisting of a main filter 74 and a stand by filter 76 provided on line. The stand by filter 76 is provided for diverting the coating composition in case of chocking of the filtering arrangement. The apparatus further includes a flow control valve 80 for controlling the feeding of coating composition from the pump 68 to the spraying guns. The control valve also controls the flow of process air from the air inlet 82 and air inlets to the pump 68. Still further the apparatus includes a programmed logic controller arrangement 100 equipped with sensors 70 for controlling the flow, viscosity and temperature of coating composition being fed to the spraying guns. The guns are cleaned by solvent to avoid scaling inside the spraying system. A separate frame for filter-mist mounting, to avoid the physical contact between spray booth and filter-mist, is provided. It helps to avoid transfer of vibration to spray guns. On the same frame, filter, differential gauges as well as flow regulators and diaphragm pump are mounted. The provision of the flash-off conveyor 30 helps to gain time for setting the material over the article. Alternatively, it helps to take out the excess material from the bottom side of the article. 18 The oven conveyor 22 conveys the article, which is conveyed from flash-off conveyor to curing zone for on-line curing. The structure of the conveyor may be SS or like material having a teflon-coated belt to convey the article. Conveyor cooling arrangement or exhaust of heat arrangement [not shown] avoids excess heating of conveyor. The curing station 20 is a closed box type structure wherein insulated panels are mounted on angle frame of suitable material. There is an arrangement to mount ultraviolet lamp or infra-red lamp or any other radiation device, adjustments for movements as well as cooling arrangement to improve the effectiveness of curing. Necessary cooling arrangement of exhaust is fitted in the booth 20. A cooling blower is provided at the bottom side of booth to avoid overheating of booth and conveyor. All Conveyors have individual gear motors with chain and sprocket arrangements. The controls of speed is effected through frequency modularisation via inverters. The spray conveyor and the flash off conveyor drives operate the drives attached to a single gear motor. Water bath heating system heats the material uniformly & individual temperature controllers maintain the set temperature. Necessary heat exchangers and pumps may be provided. If required additional heating system like strip heater / heat tracer can be incorporated. 19 Excess material sprayed during spraying operation is therefore collected by three ways in the centralized collection recycle pot, viz. the mist collected in the de-mister, spraying material collected from the spraying booth & excess sprayed material collected from the conveyor through the belt scrappec To make use of material in the recycle pot the re-cycle system is inceluded (refer Fig. 3), by which coating material is sucked through a pump and passed through filter system back to the feed tank. The booth is also provided with a wire mesh to avoid entry of other solid particles/waste in the re-cycle pot. The excess-sprayed material thus collected in the pot is pumped through strainers fitted in the pot. Provision of two filters, in parallel, is made in order to keep the process constant. In the event one of the filter gets chocked, the process continues with the second filter. Audio-visual signal is given if the filter gets chocked in order to enable the operator to clean or replace the clogged filter. A feeding tank is mounted on a rigid frame [not shown]. Slide [not shown] is provided for easy operator access. This contains virgin spraying material recycled material and re-circulated material. At any given time during the operations, the ratio of the virgin material to recycled material to re¬circulating material is approximately 1: 1 : 6. Arrangement has been made for collecting recycled material from centralised waste collection system. The provision of a level sensor 62 is made in order to get clear indication of low / high level of material inside the tank. Separate control panel boxes are provided having all electrical as well as pneumatic control elements. All operator controls are placed in a separate control box near the machine. Provision of cooling system is made to 20 maintain air circulation inside both the boxes, which eliminates overheating of controls by which working life of elements will be improved. The man, machine interface will be on the front panel of the control box. It helps the operator to operate the system smoothly. Provision is made of a buzzer and fault indicator. Viewing doors are provided on either side of the booth. It helps to set the gun as well as monitor the process easily. " PLC System : PLC 100 controls all the operations of the system. It includes two mode of logic operations the auto mode and the manual mode: In the manual mode, all the devices including the motors are operated using push buttons and selector switches mounted on the machine console. Manual mode involves the following: 1. spray booth off/on 2. curing booth off/on. 3. spray gun off/on. 4. spray conveyor offon. 5. curing booth conveyor offon. Auto mode involves the following: 1. Auto cycle start - input 2. UV lights switched on in the curing booth output selected in manual mode. 21 3. Curing booth conveyor switched on - speed can beset through drive/inverter. 4. curing booth cooling fan/blower switched on 5. strip heater switched on. 6. alarm buzzer to alert operator. The time delay between each of these steps can also be set. i) Sequential ON/OFF logic - Auto / Manual ii) Process monitor for processes like heating of spraying material, conveyor speed, usage of lamp hours, shift data, etc. iii) Warning signals - liquid level control, clogging of filters, blockage of components, iv) Fault Indicators like : a) Air Pressure Low b) Emergency OFF c) Motor trip ADVANTAGES: Manual intervention is avoided at all the stages keeping in mind the safety aspects of the operator. The curing booth is protected properly to avoid leakage of curing rays. This new system in accordance with this invention reduces the level of air pollution to the tune of 50%. 22 Control Panel is provided to keep visual track on the conditions and life of lamps. Conveyor height is adjustable for ease of operation. Material saving. While considerable emphasis has been placed herein on the structures and structural interrelationships between the component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principals of the invention. These and other changes in the preferred embodiment as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. 23 I Claim: [1] A process for coating articles with a coating composition, typically a lacquer consisting of the steps of conveying the articles to be coated via a moving conveyor into an enclosed booth; spraying the articles with the pressurized coating composition in the enclosed booth via at least one spraying gun , collecting the excess coating composition: at or near the base of the booth, by extracting the free coating composition in the ambient environment of the booth by suction and feeding the extracted material at or near the base of the booth; by scrapping the excess coating composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the enclosed booth; recycling the excess material collected at the base of the booth to the feed tank via a recycling line; re-circulating excess pressurized coating composition from the at least one spraying gun to the feed tank via a re-circulating line; conveying the coated articles from the enclosed booth to a curing station for curing of the coated articles. [2] A process for coating articles with a coating composition, as claimed in claim 1, in which the articles are optionally pretreated by selecting one or more methods of treatment from a group of 24 treatments which include flaming , ionization, primer coating, cleaning, degreasing, conditioning and the like. [3] A process for coating articles with a coating composition, as claimed in claim 1, in which the process optionally includes aligning the articles before conveying them to the enclosed booth. [4] A process for coating articles with a coating composition, as claimed in claim 1, in which the curing of the coated articles is done by incident radiation such as with the help of ultra violet rays, infra red rays including far / short wave, infra red rays and / or micro waves / heater and hot air. [5] A process for coating articles with a coating composition, as claimed in claim 1, in which the extracted free coating composition in the ambient environment of the booth is filtered before feeding the extracted material at or near the base of the booth. [6] A process for coating articles with a coating composition, as claimed in claim 1, in which the articles are displaced via the conveyor through the enclosed booth at speeds controlled between 1 meter per minute to 50 meters per minute. [7] A process for coating articles with a coating composition, as claimed in claim 1, in which the process optionally includes the step of adjusting the spraying guns to deliver high volume at low pressure coating compositions to the spraying area. 25 [8] A process for coating articles with a coating composition, as claimed in claim 1, in which the process optionally includes the step of adjusting the spraying guns to deliver low volume at high pressure. [9] A process for coating articles with a coating composition, as claimed in claim 1, in which the process optionally includes the step of pre heating the coating composition before spraying for adjusting the viscosity of the coating composition. [10] A process for coating articles with a coating composition, as claimed in claim 9, in which the preheating step is provided just before spraying. [11] A process for coating articles with a coating composition, as claimed in claims 9 and 10, in which the preheating is achieved by using hot water. [12] A process for coating articles with a coating composition, as claimed in any one of the preceding claims, in which the coating composition includes natural or synthetic polymeric material, typically a lacquer. [13] Apparatus for carrying out a process for coating articles with a coating composition, typically a lacquer as claimed in any one of the preceding claims consisting of a spraying booth fitted with at least one spraying gun for spraying the coating composition on the articles to be coated; 26 a curing station where coated articles are led for curing; a conveyor for conveying the articles to be coated from the spraying booth to the curing station; the spraying booth defined by a recycling pot at the operative base of the booth and a coating composition mist extraction arrangement at the operative top of the booth and means to permit ingress and egress of a conveyor bearing articles to be coated; a feed tank for supplying coating composition to the spraying gun/s in the spraying booth; means for on line pressurizing the coating composition to be supplied to the spraying guns/s; feeding means for extracted feeding coating composition at or near the base of the booth; scrapping means for scrapping excess coating composition from the moving conveyor and allowing the scrapped material to fall by gravity to the base of the booth; recycling means for recycling the coating composition collected at the base of the booth to the feed tank via a recycling line; re-circulating means for re-circulating excess pressurized coating composition from the at least one spraying gun to the feed tank via a re-circulating line. [14] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, which includes a pre treatment booth for pre treating the articles to be coated by one or more methods of treatment from a group of treatments which include 27 flaming , ionization, primer coating, cleaning, degreasing, conditioning and the like. [15] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which the mist extraction arrangement includes a filter for filtering the coating composition mist before leading it to the base of the spraying booth. [16] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 15, in which the filter includes a perforated bowl with baffles. [17] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which the re¬circulating line includes an online filter. [18] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which the feed tank is provided with a level indication means. [19] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which the recycle line includes a strainer, filter and pumps means for straining and filtering the coating composition to be recycled to the feed tank. [20] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which at least one heat 28 exchanger is provided between the feed tank for heating the coating composition for adjusting its viscosity. J**; _ [21] Apparatus for carrying out a process for coating articles, with a coating composition, as claimed in claim 13, in whicn strlp heater provided just before feeding pressurized coating composition to the spraying gun for heating the coating composition and thereby adjusting the viscosity of the coating composition being fed to the spraying gun. [22] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, which includes a differential gauge controlled filtering arrangement provided between the feed tank and the spraying gun for filtering the coating composition being fed to the spraying gun. [23] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 22, in which the filtering arrangement includes a stand by filter for diverting the coating composition in case of chocking of the filtering arrangement. [24] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, which includes a control valve for controlling the feeding of coating composition from the feed tank to the spraying gun/s. 29 [25] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, which includes a programmed logic controller arrangement equipped withi sensors for controlling the flow, input and outputs viscosity and temperature "of coating composition being fed to the spraying gun/s. [26] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which alignment means are provided for guiding the articles on the conveyor leading to the spraying booth. [27] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in claim 13, in which the conveyor includes a flash off conveyor located between the spraying booth and the curing station for removing flashings of the coating composition from the coated articles. [28] Apparatus for carrying out a process for coating articles with a coating composition, as claimed in, claim 13, in which the conveyors are provided with cooling means to cool the coated articles. [29] A process for carrying out coating of articles with a coating composition, as described herein with reference to the accompanying drawings. 30

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1138-mum-2002-claims(granted)-(05-03-2003).doc

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