EP1490870A1

EP1490870A1 - Production of dvd cards and other discs of noncircular shape

Info

Publication number: EP1490870A1
Application number: EP03714868A
Authority: EP
Inventors: Ulrich Speer
Original assignee: Steag Hamatech AG
Current assignee: Steag Hamatech AG
Priority date: 2002-03-25
Filing date: 2003-03-21
Publication date: 2004-12-29
Also published as: JP2006510139A; JP4114799B2; DE10213273A1; DE10213273B4; US20050126698A1; WO2003081583A1; CA2479816A1; CN1643588A; TW200306562A

Abstract

The invention relates to a device for assembling at least two noncircular substrates (1, 2) that have the same circumferential shape and that are provided with center holes (5, 6), especially for producing an optical data carrier. The aim of the invention is to provide a method and device with which the substrates can be assembled congruently and glued together flawlessly. For this purpose, the inventive device comprises a receiving unit (3) adapted to the center holes of the substrate, which receives the substrates (1, 2) so that they are spaced apart and rotatable about a common axis (8); an alignment device (10) for aligning the substrates (1, 2) with at least one stop (11); and a displacement unit for engaging the substrates with the stop. The invention also relates to a method for assembling substrates of the aforementioned kind.

Description

Manufacture of DVD cards and other discs with non-round shapes

The present invention relates to an apparatus and a method for joining together at least two non-circular substrates having inner holes with the same circumferential shape, in particular for forming an optical data carrier, such as DVD cards.

Optical storage media have become the preferred storage media and are widely used not only in computers but also in music and image playback devices. The commercially available form of such storage media are circular disks with centered inner holes, which are inserted into corresponding reading or writing devices in order to transfer data to the disks or to read data stored on them.

In addition to the CDs, which are essentially made up of only one substrate, DVDs have become customary, which are composed of substrates stacked on top of one another with respective storage areas and provide a higher storage density. In the conventional circular DVD discs, at least two substrates in the form of round disks are joined by gluing. A known manufacturing process for a DVD uses a liquid adhesive that is applied to one of the substrates. The two substrates are then brought together and then this composite is spun out together, as described, for example, in EP-A-0 833 315. As a result, the liquid adhesive is evenly distributed between the substrates due to the centrifugal forces of the spinning process. Excess liquid adhesive emerges from the edges of the bonded substrates and can be removed. Furthermore, the required layer thickness of the adhesive is set by the spinning. This DVD disk is then irradiated with light to harden the adhesive. Another method for joining disc-shaped substrates is known from EP-A-0 855 703, in which an adhesive film is used for joining the substrates.

In the case of CDs which are constructed from only one substrate, non-circular shapes are already taken into account, such as, for example, CDs in card format and also CDs with fancy shapes, such as, for example, a fir tree shape and heart shape, which are not rotationally symmetrical. To produce a corresponding DVD card, two substrates with a non-circular shape must be congruently joined. The joining techniques used in the rotationally symmetrical substrate disks can cause problems with rectangular formats (DVD cards) or fantasy formats (Christmas tree). For example, in the known method described above for joining disc-shaped substrates with a liquid adhesive, the substrates do not lie securely one above the other when the adhesive is ejected. Therefore, after the liquid adhesive is ejected, the substrates are misaligned. The DVD substrates would then have to be aligned again, which can then destroy the adhesive layer of the liquid adhesive and introduce defects (e.g. air bubbles) into the adhesive layer.

In the aforementioned EP-A-0 833 315, the circular substrates with an adhesive applied therebetween are received via central inner holes on a protrusion which is then expanded to center the two substrates, thereby correcting misalignment.

Reference is also made to WO 86/05620 and EP 0 479 340 A2, both of which show card-shaped or rectangular data carriers with ring-shaped data storage areas. In EP 0 479 340 A2, the information memory card is made up of two substrates.

The present invention is therefore based on the object of an apparatus and a method for joining two non-circular ones To provide substrates, the bonding can be carried out without errors and the substrates are joined congruently.

This object is achieved by a device and a method for joining together at least two non-circular substrates with the same circumferential shape, in particular for forming an optical data carrier, according to claim 1 and claim 16, respectively.

The device according to the invention has a receiving unit adapted to the inner holes of the substrates for holding the substrates at a distance and rotatably receiving them about a common axis, an aligning unit for aligning the substrates with at least one stop and a movement unit for engaging the outer substrate edges of the substrates the attack. The substrates, which are spaced apart on the receiving unit, are brought into engagement with the stop by a relative movement, as a result of which they rotate about the common axis and are aligned congruently. You can then combine them into a DVD card, for example. The device is thus simple and flexible and can be adapted to a wide variety of non-circular circumferential shapes of the substrates.

In an advantageous embodiment, the alignment unit has at least one counter stop. The stop and the counter stop align the substrates arranged between them on the receiving unit particularly precisely.

The movement unit can advantageously move the receiving unit, the stop and / or the counterstop and can thus be flexibly adapted to a wide variety of requirements.

It is particularly advantageous if the receiving unit can be moved in the direction of the counterstop by the stop. The substrates are first aligned in the direction of rotation by a first contact with the stop. Then the recording unit is additionally together with the taken substrates moved by the stop against the counter-stop, so as to ensure a particularly precise alignment of the substrates.

According to an advantageous aspect of the invention, the stop and / or the counterstop is adapted to at least part of a substrate edge of the substrates. This means that substrates with complicated circumferential shapes, such as the shape of a fir tree or a heart, can also be reliably aligned.

It is furthermore advantageous if the stop and / or the counterstop have projections with stop surfaces pointing towards the substrates, which are adapted to at least a part of a substrate edge of the substrates, the projections being at a distance from one another which is the distance between those arranged on the receiving unit Corresponds to substrates. As a result, the alignment unit can be designed with a lighter weight and the effort required is reduced.

According to a further advantageous aspect, the stop and / or the counter-stop can have at least one cylinder, the longitudinal axis of which runs essentially parallel to the common axis of rotation. The cylinder (s) then come into contact with the substrate edges only at essentially point-like locations. As a result, tilting of the substrates can be avoided. On the other hand, the use of cylinders is particularly advantageous since they can be adapted to different forms of substrates by changing the position.

According to an advantageous embodiment, the receiving unit has a receiving pin with a device for holding the substrates at a distance. The inner holes of the substrates can easily be centered relative to one another by such an arrangement and the rotating alignment takes place on the locating pin. After aligning the substrates, the substrates can then be pressed together on the receiving pin. According to an advantageous aspect, the device for holding the substrates at a distance comprises movable lugs, movable balls and / or spring washers which, for example, move into the interior of the receiving pin when a suitable force is applied, so that the substrates can be pressed together.

Furthermore, the holding unit could have at least two separate holding pins which hold the substrates separately. The substrates can then advantageously be fed to previous processes, for example a coating with an adhesive, on the individual holding pins.

Advantageously, the device additionally has a unit for applying an adhesive to at least one of the substrates. The adhesive then does not have to be applied in a separate process step.

If the adhesive is an adhesive film, this is particularly advantageous because, when the substrates are joined together, there is no contamination of the device by ejected liquid adhesive.

A joining unit for compressing the substrates can advantageously be provided. Finally, it is also advantageous if a vacuum chamber is provided in which the substrates are received on the receiving unit. By joining in a vacuum, errors in the adhesive or Connection layer of the two substrates can be avoided.

The method according to the invention has the following steps: 1) arranging the substrates on a receiving unit adapted to the inner holes in such a way that they are spaced apart and held rotatable about a common axis; 2) Aligning the substrates by engaging outer edges of the substrate with at least one stop and rotating the substrates around the common axis; and 3) joining the substrates. According to an advantageous aspect of the

In the method, the rotation of the substrates is brought about by engaging the substrates with at least one stop and / or a counter stop. The pre Parts of the method according to the invention correspond to the advantages mentioned above with regard to the device according to the invention.

Further features, advantages and details of the invention are explained below on the basis of preferred exemplary embodiments with reference to the figures. Show it:

1a shows a plan view of two substrates for a DVD card recorded on a preferred embodiment of a recording unit;

1 b is a schematic sectional view along the line 1 b-1 b in Fig.

1a;

2a shows a schematic plan view of a device according to a first exemplary embodiment of the invention; Fig. 2b is a schematic sectional view of the device of Fig. 2a along the line 2b-2b in Fig. 2a;

3a shows a schematic top view of a device according to a second exemplary embodiment of the invention;

3b is a schematic sectional view of the device of FIG. 3a along the line 3b-3b in FIG. 3a;

4a shows a schematic plan view of a device according to a third exemplary embodiment of the invention;

Fig. 4b is a schematic sectional view of the device of Fig. 4a along the line 4b-4b in Fig. 4a; 5a shows a schematic plan view of a device according to a fourth exemplary embodiment;

Fig. 5b is a schematic sectional view of the device of Fig. 5a along the line 5b-5b in Fig. 5a;

6a shows a schematic plan view of a device according to a fifth exemplary embodiment of the invention; and

Fig. 6b is a schematic sectional view of the device of Fig. 6a along the line 6b-6b of Fig. 6a. Fig. 1 a shows schematically two superimposed substrates 1 and 2 with a rectangular shape with round data storage parts formed in the central area. The two substrates 1 and 2 are also referred to as DVD half sides, which are to be joined together to form a DVD card. As indicated in Fig. 1 a by the arrows, the two substrates 1 and 2 are arranged rotatably about a common axis of rotation D, which runs through the centers of the data storage parts.

1 b schematically shows a preferred embodiment for a receiving unit 3 for use in the device or the method according to the invention. On the receiving unit 3, the two substrates 1 and 2 shown in FIG. 1 a are spaced apart and about the common axis of rotation

D rotatably arranged. For this purpose, the receiving unit 3 has a cylindrical pin 4 which is designed in such a way that the two substrates 1 and 2 are spaced apart and rotatably held thereon. The outside diameter of the

Pin 4 is adapted to inner holes 5 and 6 of substrates 1 and 2 to receive them centered. In the preferred embodiment, a movable projection 7 is provided on the receiving unit 3 in order to maintain a predetermined distance between the substrates 1 and 2. The common axis of rotation D of the two substrates 1 and 2 is defined by the central axis 8 of the pin 4.

In the method according to the invention, the aligned substrates are preferably pressed onto one another on the receiving unit 3 by a joining unit, not shown. The projection 7 has a first position in which, for example, the substrate 1 rests thereon, and a second position in which a movement of the substrate 1 to the substrate 2 is made possible. The projection 7 can thus be controllably countersunk into the interior of the pin, for example for joining the substrates 1 and 2, so that the upper substrate 1 can be applied to the lower substrate 2 and connected to it by suitable pressure. The projection 7 is only shown schematically in the figures, but it should be clear that it can be designed as a movable nose, as movable balls or by spring washers. Furthermore, a pin or spacer pin, which is particularly suitable for a precisely centered pick-up of the substrates, as described in German laid-open publication DE 199 27 514 A1 and to which reference is hereby made to avoid repetition, can advantageously be used in the invention.

However, instead of the one-piece pin 4, the holding unit could also have at least two holding pins, on which, for example, the substrates are initially held separately in order to be fed to different processes. For the assembly, the locating pins are centered with respect to one another in a suitable manner. For example, they can have complementary shapes and can be brought into engagement with one another to align the substrates. The subsequent joining of the substrates can in turn be carried out on the centering pins.

The preferred exemplary embodiments of the device according to the invention shown in FIGS. 2a to 6b all have the receiving unit 3 in accordance with FIG. 1b. Furthermore, they each comprise an alignment unit and a movement unit, not shown, for moving elements of the alignment unit and / or the receiving unit. The directions of movement of the corresponding elements are indicated by arrows in the figures. In order to avoid repetitions, the same reference symbols are used in the figures for the same or equivalent elements.

An alignment unit of a first exemplary embodiment of the device according to the invention, which is shown schematically in FIGS. 2a and 2b, has a stop 11 which is moved in the direction of arrow A in FIGS. 2a and 2b by a movement unit, not shown. The receiving unit 3 of this embodiment is movable. The stop 11 has a shaft 12 extending in the direction of movement of the arrow A, at the end of which facing the substrate an edge contact 13 is formed which extends transversely to the shaft. The edge system 13 has two projections 14 and 15, the end surfaces of which point towards the substrates form contact edges 16 and 17 which can be brought into engagement with respective substrate edges 21 and 22 of the substrates 1 and 2, as can best be seen in FIG. 2b is. The projections 14 and 15 are at a distance from one another which corresponds to the distance at which the substrates 1 and 2 are held on the receiving unit 3 by the projection 7. Thus, the contact edges 16 and 17 essentially only engage with the substrate edges 21 and 22, the contact edges 16 and 17 having a complementary shape to at least some of the substrate edges 21 and 22 of the substrates 1 and 2. In the exemplary embodiment shown with the rectangular substrates 1 and 2, this means that the contact edges 16 and 17 run flat and vertical.

Furthermore, the alignment unit 10 has a counter stop which, in the exemplary embodiment in FIGS. 2a and 2b, comprises two cylindrical pins 24 and 25 which are used to align the two substrates 1 and 2 with substrate edges 27 and 28 of the two substrates at points 29 and 30 in Come in contact.

For joining the two rectangular substrates 1 and 2 to form a DVD card, these are initially received through the inner holes 5 and 6 on the pin 4, the distance held by the pin 4 between the two substrates 1 and 2 being the distance between the two projections 14 and 15 of the stop 1 1 corresponds. At this point in time, the two substrates 1 and 2 are generally not aligned one above the other. Furthermore, when the substrates 1 and 2 are picked up, the receiving unit 3 is also so far away from the pins 24, 25 that the substrates 1 and 2 preferably do not come into contact with them. The stop 11 is then moved by the movement unit in the direction of the substrates 1 and 2 until the contact edges 16 and 17 come into engagement with the substrate edges 21 and 22. The movement unit continues the movement of the stop 11 so that it presses against the substrate edges 21 and 22. This causes the substrates 1 and 2 to rotate on the pin 4 until the contact edges 16 and 17 lie completely against the substrate edges 21 and 22 and these are arranged congruently in plan view. At this time, the two substrates 1 and 2 are arranged essentially aligned on the receiving unit 3. By a further movement of the stop 11 against the substrates

1 and 2, these are moved together with the receiving unit 3 in the direction of the fixed pins 24 and 25. When finally the substrate edges

27 and 28 of the substrates 1 and 2 lie against the points 29 and 30 of the pins 24 and 25, perfect alignment is achieved.

Alternatively, the receiving unit 3 could also be held in place, the substrates 1 and 2 being aligned solely by the movement of the stop 11.

Figures 3a and 3b show a further embodiment of the device according to the invention. The device shown in FIGS. 3a and 3b is particularly suitable for joining rectangular substrates 1 and

2 designed. As in the previous exemplary embodiment, the substrates 1 and 2 are spaced apart and rotatably received on a pin 4. An alignment unit of the exemplary embodiment in FIGS. 3a and 3b has a stop 11 which can be moved in the direction of arrow A by a movement unit (not shown) and has contact edges 16 and 17 which are provided with

Substrate edges 21 and 22 of the rectangular substrates 1 and 2 are brought into engagement. In this embodiment, too, is a recording unit

3 can be moved together with the substrates 1 and 2 and is moved by the stop 11 in the direction of a counter-stop which has two fixed counter-stops 32 and 33. The two fixed counter stops 32 and 33 have walls 35, 36, 37 and 38. When the stop 11 presses the receiving unit 3 together with the substrates 1 and 2 in the direction of the counter stop, the walls 36 and 37 come with the long sub stratkanten 27 and 28 of the substrates 1 and 2 in engagement. The walls 35 and 38, on the other hand, come to rest on short substrate edges 40 and 41, which particularly helps in the precise alignment of the rectangular substrates 1 and 2.

In the exemplary embodiment in FIGS. 4a and 4b, in addition to cylindrical pins 24 and 25, which are also provided in the exemplary embodiment in FIGS. 2a and 2b, a counterstop has further fixed cylindrical pins 43 and 44, which at points 45 and 46 have short substrate edges 40 and 41 of the substrates 1 and 2 come to rest and are particularly advantageous when aligning the substrates 1 and 2, in particular with a rectangular shape. In comparison to the embodiment of FIGS. 3a and 3b, however, there is still greater freedom in the device according to FIGS. 4a and 4b in the choice of the circumferential shape of the DVD cards which are finally combined.

FIGS. 5a and 5b show an embodiment of the device according to the invention, in which a receiving unit 3 is fixed and a stop 11 of an alignment unit is moved in the direction of arrow A by a movement unit, not shown. As a result, contact edges 16 and 17 of the stop 11 are brought into engagement with substrate edges 21 and 22 of the substrates 1 and 2 for a rotating alignment movement of the substrates.

Furthermore, the alignment unit of the exemplary embodiment in FIGS. 5a and 5b has a movable counter-stop 47 which has a shaft 48 and an edge contact 49 which is arranged at the end of the shaft 48 pointing towards the receiving unit 3. The edge system 49 has contact edges 53 and 54 formed on projections 51 and 52.

The counter-stop 47 is, so to speak, the mirror image of the stop 11 and is arranged on the side of the substrates 1 and 2 opposite the stop 11. The counter-stop 47, like the stop 11, is moved by the movement unit (not shown) in the direction of arrow B onto substrate edges 27 and 28 of the rectangular substrates 1 and 2 until finally the attachment position edges 53 and 54 come into engagement with the substrate edges 27 and 28 of the substrates 1 and 2. As a result of this movement of the two stops 11 and 47 towards one another and against the substrates 1 and 2 rotatably arranged on the fixed receiving unit 3, the rectangular substrates are aligned congruently and can then be combined to form a DVD card.

FIGS. 6a and 6b show a further exemplary embodiment of the device according to the invention, which has an alignment unit adapted to an imaginary shape. Two heart-shaped substrates 60 and 61 are to be added to a DVD, which is to be used, for example, as a valentine or as another gift item. The two heart-shaped substrates 60 and 61 are spaced and rotatably received by their inner holes 62 and 63 on a pin 4 of a movable receiving unit 3. A stop 66 has a shaft 67 and an edge contact 68, which are arranged at the end of the shaft facing the substrates. The stop 66 is moved in the direction of the arrow C towards the substrates 60 and 61 by a movement unit, not shown. The edge system 68 is adapted to substrate edges 70 and 71 of the heart-shaped substrates 60 and 61. In particular, the edge system 68 has two projections 73 and 74, at the ends of which system edges 75 and 76 are formed.

The edge system 68 is designed such that it can include the substrate edges 70 and 71 of the heart-shaped substrates 60 and 61. For this purpose, the edge system 68 preferably has a certain elasticity, so that when it moves in the direction of the arrow C of the stop 66 it grips over the substrate edges 70 and 71, so to speak, and comes into engagement therewith. As a result of the further movement of the stop 66 against the substrates 60 and 61 received on the receiving unit 3, the receiving unit 3 is moved in the direction of a fixed counterstop which has cylindrical stop pins 78, 79, 80 and 81 which at points 83, 84, 85 and 86 come to rest on the substrate edges opposite to the substrate edges 70 and 71 of the substrates. As already indicated, the counter-stops can be omitted in a modification of the exemplary embodiments described above. The receiving unit 3 is then held in place and the stop 11 or 66 is moved against the substrate edges of the substrates. Furthermore, the movable stop, like the counter-stops of the exemplary embodiments in FIGS. 2a, 2b, 4a, 4b, 6a, 6b, could have one or more movable cylindrical pins which are arranged with their cylinder axes parallel to the common axis of rotation D, i.e. transversely to the substrate edges, and only come into contact with the substrates at points. This allows great flexibility in the processing of different shapes of the substrates, since a stop consisting of cylindrical pins can be easily and quickly adapted to any shapes of the substrates by suitable movement or positioning of the pins. The movable pins can be arranged on one side of the substrates or around the substrates.

After aligning the two substrates, they are joined together in a congruent manner. For this purpose, an adhesive is provided, for example, even before the substrates are aligned on a joining side of at least one of the substrates , The device can have a unit suitable for applying the adhesive.

The substrates are preferably joined together in a vacuum chamber, since errors in the connection layer between the substrates, such as air bubbles enclosed in the adhesive, can be avoided.

The joining unit provided for compressing the substrates can be a cylinder or a membrane station. Such a membrane station is described, for example, in the non-prepublished patent application DE 101 00 427, which goes back to the applicant and is used here to avoid of repetitions is incorporated by reference. Such a membrane station is particularly suitable for use with a vacuum chamber.

The device and the method according to the invention thus enable the production of non-circular optical data carriers which are composed of at least two substrates, with a precisely aligned and reliable joining of the substrates even with complicated circumferential forms being achieved by simple measures.

Claims

claims

1. Device for joining together at least two non-circular substrates (1, 2; 60, 61) having inner holes (5, 6; 62, 63) with the same circumferential shape, in particular for forming an optical data carrier, the device having the following :

- A receiving unit (3) adapted to the inner holes of the substrates for the spaced and rotatable receiving of the substrates (1, 2; 60, 61) about a common axis (8); - An alignment unit (10) for aligning the substrates (1, 2; 60, 61) with at least one stop (11; 66); and a movement unit for engaging outer substrate edges (21, 22, 27, 28, 41, 42; 70, 71) of the substrates with the stop.

5 2. Device according to claim 1, characterized in that the alignment unit (10) has at least one counter-stop (24, 25; 32, 33; 43, 44; 47; 78 - 81).

3. Device according to claim 1 or 2, characterized in that the o movement unit, the receiving unit (3), the stop (11; 66) and / or the counter-stop (24, 25; 32, 33; 43, 44; 47; 78 - 81) moves.

4. The device according to claim 2 or 3, characterized in that the receiving unit is movable by the stop in the direction of the counter-stop 5.

5. Device according to one of the preceding claims, characterized in that the shape of the stop (11; 66) and / or that of the counter-stop (32, 33; 24, 25, 43, 44; 47; 78 - 81) at least a part o of the outer edge of the substrate (21, 22, 27, 28, 40, 41; 70, 71) of the substrates (1, 2;

60, 61) is adjusted.

6. Device according to one of the preceding claims, characterized in that the stop (11; 66) and / or the counter-stop (47) projections (14, 15; 51, 52; 73, 74) with stop surfaces facing the receiving unit (16, 17; 53, 54; 75, 76) which are adapted to at least part of the outer edge of the substrate of the substrates to be joined, the projections being at a distance from one another which corresponds to the distance at which the substrates (1, 2; 60, 61) are held on the substrates (1, 2; 60, 61) arranged on the receiving unit (3).

7. Device according to one of the preceding claims, characterized in that the stop and / or the counter-stop have at least one cylinder (24, 25; 43, 44; 78 - 81), the longitudinal axis of which runs essentially parallel to the common axis of rotation (8) ,

8. Device according to one of the preceding claims, characterized in that the receiving unit (3) has a receiving pin (4) with a device (7) for holding the substrates (1, 2; 60; 61) at a distance.

9. The device according to claim 8, characterized in that the device for holding the substrates spaced apart has movable lugs, movable balls and / or spring washers.

10. Device according to one of the preceding claims, characterized in that the receiving unit has at least two separate receiving pins.

11. Device according to one of the preceding claims, characterized in that a unit is provided for applying an adhesive to at least one of the substrates.

12. The device according to claim 11, characterized in that the adhesive is an adhesive film.

13. Device according to one of the preceding claims, characterized in that a joining unit is provided for compressing the substrates.

14. Device according to one of the preceding claims, characterized in that a vacuum chamber is provided.

15. Method for joining together at least two non-circular substrates (1, 2; 60, 61) having inner holes (5, 6; 62, 63) with the same circumferential shape, in particular for forming an optical data carrier, which has the following steps: Arranging the substrates on a receiving unit (3) adapted to the inner holes in such a way that they are held at a distance and rotatable about a common axis (D; 8);

- Aligning the substrates by engaging outer substrate edges (21, 22, 27, 28, 41, 42; 70, 71) with at least one stop and rotating the substrates around the common axis (D; 8); and

- Joining the substrates (1, 2; 60, 61).

16. The method according to claim 16, characterized in that the rotation of the substrates is brought about by bringing the substrates into engagement with the at least one stop and a counter-stop.

17. The method according to claim 15 or 16, characterized in that an adhesive is applied to at least one of the substrates.

18. The method according to claim 17, characterized in that the adhesive is an adhesive film.

19. The method according to claim 18, characterized in that the joining takes place by compressing the substrates.

20. The method according to any one of claims 15 to 19, characterized in that the alignment and assembly takes place in a vacuum.