Patent Application
20070298158
The advantages, nature, and various additional features of the invention will appear more fully upon consideration of the illustrative embodiments now to be described in detail in connection with accompanying drawings wherein:
It should be understood that the drawings are for purposes of illustrating the concepts of the invention and are not necessarily the only possible configuration for illustrating the invention.
Aspects of the present invention provide a system, apparatus and method which enable the introduction of a new (“test”) bonding material (e.g., acrylic resin/lacquer) in an optical disc manufacturing production line, e.g., a Digital Video Disc (DVD) disc production line, with maximum efficiency and minimum waste. Advantageously, a system according to the present invention is easily installable on existing DVD production lines, prevents the need to replace filters and minimizes the time that the line is out of production.
It is to be understood that the present invention is particularly applicable to DVD disc manufacturing lines, but however may be used with any disc production system including CD, video discs or any other injection molded media that utilizes a production cycle which includes disc bonding materials (e.g., acrylic resins/lacquers, etc.) for bonding together e.g. metallized polycarbonate layers.
It should be understood that the elements shown in the FIGS. may be implemented in various forms of hardware, software or combinations thereof. Preferably, these elements are implemented in a combination of hardware and software on one or more appropriately programmed general-purpose devices, which may include a processor, memory and input/output interfaces. It is noted that the method steps shown are in an exemplary sequence for illustrative purposes, and the steps are not necessarily required to be performed in the order shown.
Referring now in specific detail to the drawings in which like reference numerals identify similar or identical elements throughout the several views, and initially to
According to one aspect, a test assembly is provided, comprising a pressure vessel 103 for holding, e.g., a bonding material to be tested. In one exemplary embodiment, the vessel 103 is adapted to hold about 2 kilograms of test material. Test materials may comprise e.g., various acrylic resins or lacquer formulations, readily determinable by one of skill in the art, which may be utilized in bonding processes in optical disc (e.g., DVD) manufacturing. A pressure regulator 101 is provided which receives an air supply 100 for controlling air pressure in pressure vessel 103 as well as a control valve 107. The control valve 107 comprises a pneumatically controlled dispense valve, which utilizes compressed air to control the dispensing of resin from the dosing valve. The vessel 103 includes a feed valve 105, which may comprise, e.g., a manual valve located at a bottom of the vessel 103.
A test assembly according to the present invention may be utilized in existing optical disc production lines, e.g., a pump dispense system 106 or a pressure dispense system 108. When connected to a pump dispense system. 106, the test assembly comprises components in block 102 (e.g., components 101, 103, 105,107 and 109). Valve 109 may replace the existing OEM (original equipment manufacturer) dosing valve (not shown) in the existing pump dispense system.
When connected to a pressure dispense system 108, the test assembly comprises components in block 104 indicated in broken lines (i.e., components 101, 103 and 105, connected to an existing dosing valve 111 in the pressure dispense system).
Once the test assembly is connected to either a pump or pressure dispense system, the test material may be dispensed via dosing valves 109 or 111 to a system resin applicator (e.g., a “lacquer needle”) 113 for applying the resin to a disc in an applicator bowl 115 (e.g., a spin bowl); In either pump or pressure dispense systems, a test assembly includes a drain line 117 routed to a waste container 119 to collect the, e.g., spin-off waste when a test material is being used to prevent the test material from contaminating the original production line and the original bonding material.
According to another aspect, the existing production system (here, a pump dispense system) is intercepted (e.g., at hose 114 between the existing pump and the resin applicator needle) and the test assembly is connected thereto (e.g., the dosing valve 109 is connected to the applicator needle 113 via hose 114). The vessel and the control valve are pressurized (step 203). The existing (OEM) system is vented, e.g., by removing the existing system pressure connection, and a drain/return line (e.g., line 117) is routed from the applicator/spin bowl (holding a disc to be coated) to a waste tank (step 205). Preferably, the line 114 is flushed before and after use to prevent, e.g., material cross-contamination. The use of drain line 117 to a separate waste tank enables separate collection of the spin-off and purged test material and thus prevents inter-mixing and contamination of different bonding materials.
In step 207, the discharge line of the existing pump 505 (e.g., as shown in
The dosing process (e.g., application of the proper thickness of bonding material on a disc) may need to be revised as necessary depending on the type of test material used and its particular attributes, e.g., its viscosity, etc. (step 209). For example, typically, a layer of bonding material about 40-60 microns thick is desirable on a DVD disc, and necessary alterations to the dosing may be done in accordance with the type of test bonding material used, so as to achieve the proper thickness during application.
The signal communicating the dispense command for the existing OEM dosing valve (not shown) may be used to trigger the control valve (e.g., 107) and dosing valve (e.g., 109) in a test assembly according to the present invention to dispense the test lacquer (step 211). The test material is dispensed from the dosing valve (e.g., 109) to the system applicator (e.g., needle 113) for application onto a disc (e.g., in bowl 115), and the desired number of test discs using the test material is produced accordingly (step 213). In step 215, it is ascertained whether a new test bonding material is desired to be used; if yes, the process returns to step 201 using the new bonding material, if no, in decision block 217 it is determined if it is desired to switch back to the existing original production system. If yes, the process proceeds to step 401 of
The existing system is vented and a drain/return line is routed from the spin bowl to a separate waste container to collect any spin-off waste and prevent, e.g., material cross-contamination (step 305). Dosing parameters may be adjusted/revised as needed (step 307), depending on the type of test material being used in the system, to achieve the desired thickness and coating of the test bonding material onto a disc.
Test disc(s) may be accordingly produced with the modified system (step 309). In decision block 311, it is ascertained if another type of test material is desired to be tested; if yes, the process returns to step 301 using e.g., the new test material. If no, in decision block 313 it is determined whether it is desired to switch back to the original system. If yes, the process proceeds to step 401 of
Advantageously, the present invention enables the original disc production system to immediately return to production using the prior bonding material, without the need for draining, cleaning or replacing the filter of the existing resin system. Further, the virtually immediate switching between use of different bonding materials with ease and efficiency is facilitated, thus saving money, time and preventing waste, and in particular, reducing the amount of hazardous material required to be disposed of.
Having described preferred embodiments for system and method for testing bonding materials in optical disc production lines (which are intended to be illustrative and not limiting), it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiments of the invention disclosed which are within the scope and spirit of the invention as outlined by the appended claims. Having thus described the invention with the details and particularity required by the patent laws, what is claimed and desired protected by Letters Patent is set forth in the appended claims.
