MXPA98000318A - Ho laminator - Google Patents

Abstract

Methods and devices are provided for laminating an upper film in sheet form to a laminated substrate and at the same time obtaining substantial control over the alignment between the upper film and the substrate and reducing the formation of lamination defects.

Description

LAMPanop DB Htna GAMPQ Dg LA aWBHgtóN The present invention relates to the field of devices and methods for laminating two or more sheets of material. More particularly, the present invention relates to the field of devices and methods for laminating a laminated upper film to a laminated substrate and at the same time retaining the upper film in tension and maintaining alignment between the upper film and the substrate. ft.TpPT? BNTBS Dg LA BWBfCC? The lamination of the upper film to a substrate is well known. A particular application is in the lamination of films superior to substrates to produce blanks or laminated preforms used for license plates for vehicles, traffic signs and related objects. When a high production speed is desired, the rolling process is typically it is made with network feeding equipment in which the upper film and the substrate are fed from large rolls and laminated by press rolls. After the REF: 26598 lamination process, the laminated networks can run through a laminator or can be processed in some other way to obtain the laminated preforms used for signs, license plates and similar articles. The network feeding process provides particularly high levels of control over the rolling process as the speed of the networks can be controlled independently, so tension is also controlled in those networks, which can be critical to maintain alignment between the networks. networks and reduce waste. A disadvantage, however, is that for relatively small production where a small number of products are needed, network feeding processes can result in a substantially increased waste when measured as a percentage of product produced in the process. This additional waste can be attributed to many factors, but it is mainly due to the result of the waste produced during the adjustment procedures. Small productions are often found in situations where a relatively small number of laminated preforms such as small states are needed in the United States of America, or when any government unit must produce laminated preforms for license plates or signs at insufficient volumes. to justify the high speed network feed lamination in a line, based on both the increased waste generated as well as the high capital costs associated with the equipment. Current technology available to produce laminated preforms for license plates and signs at low volumes typically involves vacuum lamination devices which use vacuum to provide rolling pressure or stacks of manually operated press rolls on which a laminated top film is fed and a laminated substrate. However, these devices are typically slow, require a significant amount of work by part and can result in a significant amount of waste due to poor alignment control. As a result, there is a need for a low volume lamination process and devices for laminating a laminated top film to a laminated substrate.

BRIEF DEGRCRIPT? W DK IA TUVEMCIÓH The present invention provides a method and devices for laminating a laminated top film to a laminated substrate and at the same time obtaining substantial control over the alignment between the top film and the substrate and reducing the formation of lamination defects. The invention allows the operator to align the sheets or sheets before rolling and then perform the rolling process and at the same time maintain the alignment. The alignment is maintained by rolling only a portion of the sheets together in a contact patch and then advancing the contact patch on the surface of the sheets to produce a laminated preform. further, the upper film is held in tension during the lamination, which helps to maintain the alignment between the sheets and also reduces the formation of folds, bubbles and other lamination defects common in sheet lamination processes. As a result, laminated preforms can be produced in low quantities with reduced residues in a significant amount. Another advantage of the present invention is that it provides the ability to produce a significant amount of laminated preforms with a minimum amount of work. These and other features and advantages of the present invention will become apparent upon reading the detailed description that follows, together with reference to the drawings.

BRIEF DESCRIPTION OF THE DIBDaDf3 Figure 1 is an illustrative embodiment of a laminated preform constructed in accordance with the methods of the present invention. Figure 2 is a flow diagram showing the steps of an illustrative method according to the present invention. Figure 3 is a schematic diagram showing the movement of the contact patch through a substrate according to the present invention. Figure 4 is a schematic side view of an illustrative rolling device, in accordance with the present invention in its open position. Figure 5 is a side schematic view of the rolling device of Figure 4 in the closed position. Figure 6 is a side schematic view of another illustrative embodiment of a rolling device useful in accordance with the present invention.

Figure 7 is a schematic side view of the rolling device of Figure 6 in its partially closed position.

DETAILED DESCRIPTION OF THE TUVBNCTQM As discussed above, the present invention provides methods and devices for laminating laminated top films to laminated substrates and at the same time obtaining substantial control over the alignment between the top film and the substrate. As used herein, the adjective "laminate" when used with the top film or substrate indicates that the top film or substrate has been pre-cut into a sheet of the size needed to form the desired laminated preform. The size of the sheets is such that little or no clipping is necessary after lamination to produce a usable laminated preform. In general, the present invention performs its advantages to a large extent by simulating the operation of a network feed lamination line in which the network speed of the materials being laminated can be controlled independently to provide voltage. The tension is useful to maintain precise alignment as well as to avoid folds, bubbles and other lamination defects that occur in laminated preforms. Referring now to Figure 1, in which an illustrative laminated preform constructed in accordance with the principles of the present invention is illustrated, the preform 10 comprises at least two layers including an upper film 12 and a substrate 14. In many In some cases, the present invention will be used to manufacture laminated preforms for license plates which include an aluminum substrate 14 and an upper film 12 comprising a reflective laminate with graphics or letters, or both. However, it will be understood that the methods and devices according to the present invention can be used to manufacture laminated preforms formed of two laminated layers for any purpose. The upper film 12 can be laminated to the substrate 14 using a pressure sensitive adhesive, a temperature sensitive adhesive or any other known rolling mechanism. However, in general, the present invention is more useful with those rolling mechanisms which require (in addition to other variables) pressure between the upper film 12 and the substrate 14 to complete the rolling process. The upper film 12 is typically more flexible than the substrate 14 and, when control over the rolling process is insufficient, the upper film 12 can be laminated to the substrate 14 so as to bubble between the upper film 12 and the substrate 14 or in a manner which introduces folds in the upper film 12. Both defects are undesirable and the methods and devices according to the present invention are extremely useful for removing these defects when a laminated upper film 12 is laminated to a laminated substrate 14. Now back to Figure 2, which shows a flow chart showing an illustrative method according to the present invention, the steps of the basic method will be described below, after which the illustrative devices will be described in more detail to carry out such a method. The first step 100 in the illustrative method is to align the upper film 12 and the substrate 14 with each other. Typically, the alignment will be manual, i.e., an operator will physically align the upper film and the substrate in the desired orientation, although templates or fastening supports can be provided to accelerate and possibly increase the accuracy of the alignment step. After the alignment, the method involves step 200 of detaching the top film from the substrate and at the same time retaining the alignment between the top film and the substrate. This is an important aspect of the present invention in which alignment control is one of the advantages of the present invention, particularly when it is applied to laminated top films and laminated substrates for which alignment control is critical to reduce waste and provide a laminated preform in a satisfactory manner. After the upper film has been separated from the substrate, the rolling mechanism can be prepared or activated, which is shown as step 300. This may involve removing a coating of a pressure sensitive adhesive which is provided on the substrate or the upper film, or may involve heating the substrate or the upper film, or both, to activate a temperature sensitive adhesive. Other rolling mechanisms will be well known to those familiar with the art such as UV-sensitive or light-activated materials, two-part resin-based systems, and the like. In any case, the present invention provides a method in which the alignment between the upper film and the substrate is maintained during the activation or preparation of the rolling mechanism, no matter what form it actually takes.

After the rolling mechanism is prepared, the lamination of the upper film to the substrate can begin by forming a contact patch between the upper film and the substrate shown as step 400. The contact patch is illustrated schematically in FIG. Figure 3, which shows the laminated preform 10 and, in dashed lines, the contact patch 16. The arrow in Figure 3 indicates that the contact patch 16 advances through the laminated preform 10 during the rolling process. It is preferred that the contact patch begin at one edge of the substrate 14 and the upper film 12 and advance to the opposite edge, although theoretically the contact patch 16 can initially be formed anywhere on the upper film 12 and the substrate 14 and advance to an edge, followed by its advance to the opposite edge. Step 500 in the illustrative method according to Fig. 2 is to retain the upper film 12 in tension while advancing the contact patch 16 through the upper film 12 and the substrate 14. By keeping the upper film 12 in tension , the formation of bubbles and folds together with other defects is minimized, particularly when a pressure sensitive adhesive is used as the rolling mechanism.

In essence, if the tensioning of the upper film 12 simulates the operation of a network rolling line in which the speed of one of the networks is less in relation to the other network to maintain tension during the rolling process. This tension reduces bubbles and folds and other lamination defects. The present invention simulates this operation to provide similar advantages for laminated top films, which are laminated to laminated substrates where the control provided by the network feeding machinery is not available, due to the laminated form of the upper and lower films. substrates Now a couple of illustrative devices will be described which can be used to carry out the method according to the present invention. Many other devices can be manufactured which can carry out the method according to the present invention, and the two illustrative embodiments described below are examples of only two variations. Figures 4 and 5 show a device 20 in its open position in figure 4 and in its closed position in figure 5. The device 20 includes a base 22, a lower plate 24, a top cover 30, a top plate 32 and a handle 34. The upper cover 30 is hinged about an axis defined by the pin 36 which is located in a slot 38 for movement in a generally vertical direction in which the lower plate 24 defines a horizontal plane. Also shown in Figure 4 is a substrate 14 located on the lower plate 24 and an upper film 12 placed on the upper plate 32. In the positions shown, Figure 4 shows the process according to the present invention after the upper film 12 has aligned with the substrate 14. After alignment, the upper film 12 is raised or lifted away from the substrate 14 by the upper plate 32. The joining method used to retain the upper film 12 in the position against the upper plate 32 can be various means including vacuum systems, adhesives, magnetic systems, electrostatic systems and many other mechanisms which retain the upper film 12 against the plate 32, and that subsequently release the upper film 12 after it has been laminated to the substrate 14. Such systems are well known to those familiar with the art and will not be described in greater detail. It is also preferred in the illustrative embodiment of the device 20 that the upper plate 32 comprises a somewhat flexible material provided in a generally curved profile, as shown in Figure 4. The curvature in the upper plate 32 improves the early formation of the patch 16 of contact shown in Figure 3 and further improves the movement of the contact patch through the upper film 12 and the substrate 14 during descent of the upper plate 32. Flexible materials useful for the surface of the top plate 32 include, but are not limited to: pure rubber rubber (approximately 40 durometer), neoprene (preferably durometer 60-100) and silicone. Alternatively, the upper plate 32 may be flat provided it is constructed of a material flexible enough to form the desired contact patch 16 as illustrated in Figure 3 when the upper plate 32 is rotated about the 36 turning point. In such an embodiment, it may also be desirable to move the position of the turning point 36 even further below the plane defined by the lower plate 24 compared to what would happen if the upper plate 32 were curved, as shown in the figure. 4. The movement of the turning point 36 causes the edge of the upper plate 32 closest to the turning point 36 to raise the lower plate 24, as shown in Figure 5. This happens after the upper film portion 12 and the substrate 14 have been laminated by the movement of the contact patch 16.

Another aspect of the device 20 shown in Figure 4 is the position of the pivot point 36 about which the upper cover 30 rotates. As shown in Figure 4, the pivot point 36 is located below the plane defined by the upper surface of the lower plate 24 when the device 20 is in its open position with the cover 30 raised. The pivot point 36 is constrained downward by a flexible member, such as a helical spring 40 which can be provided with a precompression or a load by means of a screw 42, as generally shown in Figure 4. Now, with reference to figure 5 shows the turning point 36 in its highest position, where it is essentially equal to the height of the upper surface of the lower plate 24 when the upper cover 30 and the upper plate 32 are lowered to complete the rolling process. The movement of the turning point 36 upwards while the contact patch 16 moves through the upper film 12 and the substrate 14 serves to provide tension in the upper film 12 during the rolling process with the proviso that the portion of The upper film 12 has not yet been laminated to the substrate 14 and remains attached to the upper plate 32 until lamination to the substrate 14 occurs. If the upper film 12 is released from the upper plate 32 before lamination, the tension and, potentially, the alignment with a potential increase in the introduction of bubbles and folds in the upper film 12 is also potentially lost. It is preferred that the placement of the pivot point 36 starts below the plane defined by the lower plate 24 when the upper plate 32 is in its open position. As the upper plate 32 rotates around its pivot points 36, it is preferred that the pivot points be raised. It is further preferred that the center or axis of rotation, defined by the pivot points 36, rise not beyond the plane defined by the upper surface of the lower plate 24, although, in some cases, the pivot point may be increased above of this plane. It will be understood that although the compression spring 40 is shown as a restriction element of movement of the pivot point 36 from its position below the plane of the lower plate 24 to its equal position with the plane of the lower plate 24, the point 36 rotation can alternatively restrict the tension from the turning point 36 below. In conjunction with the device 20, any number of laminating mechanisms can be used to laminate the upper film 12 to the substrate 14, which include pressure sensitive adhesives which, the view shown in FIG. 4, typically require removal. of a liner or coating of the upper film 12 or the lower substrate 14, or both. However, as discussed above, any suitable rolling mechanism can be used together with the device 20 to laminate the upper film 12 to the substrate 14. Now, returning to FIGS. 6 and 7, another illustrative embodiment of a device 50 is shown. which can be used to carry out the method according to the present invention. The device 50 operates essentially with the same basic principles of the device 20 as shown in FIGS. 4 and 5. The device 50 includes a base 52, a lower plate 54, an upper plate 62 which is attached to a member 60. rotary which rotates about an axis 66. The upper plate 62 essentially takes the form of a portion of a cylinder having a longitudinal axis running through the turning point 66. The member 60 and the upper plate 62 are suspended above the lower plate 54 by a support 70 and are mounted for manual rotation by an operator using a lever 65 and a handle 64. Of course, it will be understood that the upper plate 62 can rotate around the turning point 66 using any other means for rotation such as a motor, etc.

In the preferred device 50, the rotation of the plate 62 around the turning point 66 also causes the lower plate 54 to move horizontally, as shown by the arrow in figure 6. This movement can be established by gears, bands of synchronization or the like, which causes the rotational movement of the upper plate 62 to be converted to linear movement to move the lower plate 54. One example may involve a rack and pinion system in which the pinion operatively engages the rotation of the top plate 62 and the rack is operatively coupled to the bottom plate 54. Many other mechanisms for converting rotary motion to linear motion are also known to those familiar with the art. It will also be understood that, instead of mechanical coupling of the rotation of the upper plate 62 and the longitudinal movement of the lower plate 54, it is also possible to control the movement of both objects separately using, for example, electric motors. The speed of each motor can be controlled separately and, in such a system, it would be optimal to control the rotational speed of the upper plate 62 so that its surface velocity is less than the longitudinal speed of the lower plate 54. As a result, then it would be possible to introduce tension in the upper film 12 during the rolling process. Also as shown in Figure 6, the lower plate 54 holds the upper film 12 and the substrate 14 aligned on the upper part of the lower plate 54. In the preferred device 50, the upper plate 62 is rotated about the turning point 66 to move the lower plate 54 below the upper plate 62, as shown in figure 7. This process can be used to lift the film 12 and separate it from the substrate 14. As a result, the rolling mechanism used to laminate the upper film 12 to the substrate 14 can be activated and at the same time the alignment between the two articles is maintained. The rolling mechanism used to retain the upper film 12 and the substrate 14 against the upper plate 62 and the lower plate 54, respectively, can be any of those described above with respect to the device 20, including vacuum and magnetic forces. After the rolling mechanism has been activated, the handle 64 is rotated again to place the upper plate 62 and the lower plate 54 together to laminate the upper film 12 to the substrate 14. Figure 7 shows the rolling process in action insofar as the left side of the upper film 12 is laminated to the substrate 14 while the right side of the upper film 12 is still to be laminated to the right side of the substrate 14 and still retained against the upper plate 62. Another feature of the device 50 described in Fig. 6 and 7 is the relative ease with which the rolling pressure between the upper plate 62 and the lower plate 54 can be adjusted. This pressure can be adjusted by varying the radial distance of the upper plate 62 from its turning point 66, shown as r in Figure 6, and at the same time maintaining the position of the upper surface of the lower plate 54 of the base 52 fixed, indicated by h in Figure 6. By varying the pressure between the upper plate 62 and the lower plate 54, either of the variables or both can be adjusted. The radial distance r can be adjusted by various means, although the simplest way is by varying the thickness of the upper plate 62 on the member 60. Another useful adjustment for varying the pressure between the upper plate 62 and the lower plate 54 is adjust the height h, of the lower plate 54 above the base plate 52 while maintaining the constant radial distance r. Of course, it will be understood that many other means may be used to vary the pressure between the upper plate 62 and the lower plate 54, instead of those specifically described herein.

In another variation of the methods and apparatus described above, it will be understood that etching of the substrate can also take place simultaneously with the lamination of the laminated upper film to the laminated substrate. The engraving is typically carried out to provide a boundary or flange around the laminated preform 10 to increase stiffness. In addition, a design can be engraved on the preform 10 to further improve stiffness, or to increase the visual impact of graphics or letters. The current design of the engraving equipment is well known to those familiar with the art and will not be further described herein. This invention may take various modifications and alterations without departing from the scope thereof. Consequently, it must be understood that this. invention is not limited to the illustrative methods and embodiments described above, but to the following claims and any equivalent thereof. It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, property is claimed as contained in the following:

Claims (13)

REVIVALDICACIQNES

1. A method for laminating a laminated sheet to a laminated substrate, characterized in that it comprises the steps of: a) aligning the layer with the substrate; b) removing the layer from the substrate while maintaining the alignment between the layer and the substrate, the layer is transported by a first plate; c) activating a means for laminating the layer and the substrate to each other; d) placing a portion of the layer in contact with a portion of the substrate, the contacting portions defining a contact patch; and e) moving the first plate relative to the substrate to advance the contact patch in a propagation direction through the substrate and laminating the layer to the substrate while simultaneously tensioning the layer in the propagation direction.

2. The method according to claim 1, characterized in that the step of detaching the layer from the substrate further comprises joining the layer to the first plate using vacuum.

3. The method according to claim 1, characterized in that it additionally comprises the step of retaining the substrate in a fixed position on a second plate.

4. The method according to claim 3, characterized in that the step of retaining the substrate additionally comprises retaining the substrate using vacuum.

5. The method according to claim 1, characterized in that the first plate is generally flat and rotates about an axis, further in which the step of moving the first plate further comprises rotating the first plate about the axis and simultaneously moving the shaft in a generally orthogonal direction relative to the substrate.

6. The method according to claim 5, characterized in that the step of moving the first plate further comprises restricting the axis of movement above a plane defined by the substrate.

7. The method according to claim 1, characterized in that the first plate forms a portion of a cylinder, and in addition in which the step of moving the first plate further comprises rotating the first plate about the axis of the cylinder and simultaneously moving the substrate in a direction generally tangential to the cylinder.

8. The method according to claim 7, characterized in that the step of moving the first plate further comprises moving the layer at a speed lower than the substrate speed.

9. A laminator for laminating a laminated sheet to a laminated substrate, comprising: a) a lower plate defining a first plane in which the substrate is; b) a top plate mounted for rotation about an axis which is substantially parallel with the first plane, wherein in a first portion, the top plate is located above the first plane and the axis is located at a first distance by below the first plane, and additionally, in which in a second position, the upper plate is generally parallel to the lower plate, and the axis is located at a second distance below the first plane, the second distance is smaller than the first distance.

10. The laminator according to claim 9, characterized in that the second distance is approximately zero.

11. The laminator according to claim 9, characterized in that the surface of the upper plate next to the lower plate is curved.

12. The laminator according to claim 9, characterized in that the upper plate further comprises means for removably attaching the layer to the upper plate.

13. The laminator according to claim 12, characterized in that the means for releasably joining is chosen from the group consisting of: vacuum, adhesives, magnetic attraction and electrostatic attraction. RESULT DB LA BWBHCIQN Methods and devices are provided for laminating an upper film in sheet form to a laminated substrate and at the same time obtaining substantial control over the alignment between the upper film and the substrate and reducing the formation of lamination defects.