Patent Application
20060249249
The present invention relates to a method and apparatus for applying decorative tape patterns to window panels and, more particularly, the present invention relates to a method and apparatus for applying aligned decorative patterns in overlying relations to make the patterns more attractive.
Various types of tape have been developed that have a decorative appearance when applied to glass. For example, U.S. Pat. No. 4,192,905 to Scheibal describes a transparent strip of polymeric material used to imitate a beveled edge. The transparent strip has a wedge-shaped cross-section having an angle similar to a beveled edge. The transparent strip has adhesive on one side for affixing the strip to the glass to produce a beveled edge appearance. U.S. Pat. No. 5,840,407 to Futhey et al. describes an optical film for simulating beveled glass. The optical film has a structured surface for providing a simulated beveled appearance. The structured surface is formed of a plurality of spaced parallel grooves that form a plurality of facets that simulate beveled glass.
Various applicators have been developed for applying tape to a surface. For example, U.S. Pat. No. 6,571,849 to Erickson et al. discloses a tape applicator that includes a tape head having a base, a tape roll holder attached to the base and a tape application roller for applying a tape to a surface attached to said base, where the tape applicator includes a tape path from the tape roll holder to the tape application roller. The tape applicator includes a x-axis actuator operatively connected to the tape head for moving the tape applicator in the x-axis direction and a y-axis actuator operatively connected to the tape head for moving the tape applicator in the y-axis direction.
United States published application 2003/0109946 entitled “Computer-Aided Layout and Application of Tape” assigned to 3M Innovative Properties Company relates to techniques that enable conventional computer-aided design software applications to be used to precisely control application of tape to a surface such as a glass surface. The subject matter of this patent is incorporated herein by reference.
At paragraph 61, the 3M published application states “After identifying the set of segments, translation module 10 generates instructions 5 directing tape applicator 6 to apply tape along each path (162, 164). During the application of each segment, . . . tape applicator 6 performs all corresponding cuts intersecting the tape segment. By selecting non-intersecting tape segments, tape translation module 10 ensures that applicator 6 will not apply a tape segment on top of another tape segment. After applying and cutting the non-intersecting tape segments, translation module 10 generates instructions 5 directing tape applicator 6 to pause for manual removal of scrap tape portions that have been cut from the tape segments (165). In this manner, tape applicator 6 allows for removal of a scrap portion from a tape segment prior to applying an intersecting tape segment. Translation module 10 continues the process until traversing all of tape data 11, i.e., until instructions have been completed for forming the entire pattern (166).”
The above quoted section of the published 3M application address a concern that scrap pieces are not left on the sheet and covered by intersecting tape segments before those scrap pieces can be removed. The present invention concerns a method and apparatus for applying decorative tape patterns to a panel to enhance the appearance of the resulting pattern and avoid cutting into already applied tape as a tape dispensing head cuts other tape segments.
An exemplary process applies multiple tape segments onto a window or door panel by identifying tape segments to be applied to a panel in a pattern. The pattern is achieved by moving a tape dispensing head with respect to the panel while applying a first set of multiple tape segments from the application head as the application head is moved with respect to the panel. The tape segments of the first set are trimmed after they are dispensed onto the panel. The tape dispensing head is then moved with respect to the panel while applying a second set of multiple tape segments. To produce the desired pattern one or more of the multiple tape segments from the second set are in close proximity to one or more tape segments from the first set. The one or more tape segments of the second set are trimmed after they applied to the panel without cutting into the tape segments of the first set.
These and other features of the invention will become better understood by reference to the accompanying detailed description which is described in conjunction with the accompanying drawings.
The present disclosure is directed to patterns 10 of decorative tape applied to panels 12, such as glass sheets that that are cut to form window lites. A tape head 100 dispenses decorative ductile tape segments onto the panels to make up those patterns and a controller coordinates movement of the tape head as the tape is dispensed by the tape head.
Lead tape used to make up the patterns 10 is very ductile. In some respects, it is more difficult to apply such lead tape and then cut to a specified shape than more stiff tapes, such as ACCENTRIM™ tape. For example, bends in the lead tape that occur as the lead tape travels through the tape head tend to be retained when the tape is applied to the glass sheet. The blades of traditional cutoff tools included in tape dispensing heads are spread apart by the thicker, ductile lead tape. The ductile property of lead tape also makes it possible to apply curved patterns to the glass sheet. The tape head 100 includes features that allow smooth lengths of ductile tape 22 to be applied, that facilitate cutting of thicker, ductile tape and/or that allow curved segments of ductile tape 22 to be applied to glass sheets 12.
An exemplary tape applicator station 200 (
The tape applicator station preferably includes a frame for holding the tabletop 52. The tabletop 52 is preferably tilted to allow a user to easily place a sheet of glass 12 on the tabletop 52. Tape patterns 10 are applied to opposite sides of the glass sheet if needed. The tabletop 52 may optionally include a vacuum system for holding the sheet of glass stationary on the tabletop 52. The tabletop 52 and frame are sized to handle desired sizes of glass.
The tabletop 52 defines an x-axis and an y-axis in the plane of the tabletop and a z-axis perpendicular to the tabletop 52. The station 200 includes a x-axis actuator 68, a y-axis actuator 70 and a z-axis actuator 72 for supporting, moving, and positioning the tape head 100 at different locations on the tabletop 52. The y-axis actuator 70 includes a support arm 74 that extends in the y-axis direction of the tabletop 52. The y-axis actuator 70 is moved in the x-axis direction by the x-axis actuator 68. The y-axis actuator 70 moves the tape head 100 in the y-axis direction of the tabletop 52 along the support arm 74.
The rotary actuator 72 for rotating the tape head 100 around an axis A that is parallel to the z-axis. Any commercially available rotary actuator may be used. An example of a suitable step motor is sold under the trade name Compumotor, which is commercially available from Braas Company located in St. Paul, Minn., sold under the part number S83*135-MO-S.
The tape head 100 is illustrated in
As seen in the depiction of
The cutting mechanism 116 includes a fixed blade 112 and a moveable blade 114 that is restricted to linear movement with respect to the fixed blade. The application roller 120 is mounted to the lower base portion 106b. Referring to
In the exemplary embodiment, the tape 14 moves along the following tape head path:
1) from the tape roll holder 102 to the guide rollers 108;
2) then to the nip formed between the drive roller 110 and the pinch roller 118;
3) then to the pivotal platen 122 and over the platen;
4) then between the blades 112, 114 of the cutting mechanism 116, which are spread apart;
5) then under the application roller 120, which applies the tape 14 to the glass sheet 12.
In one embodiment, the tape head 100 is configured to minimize bending of the tape 14 along the path of travel between the drive roller 110 and the tape application roller. This reduces visible defects in the ductile tape, such as lead tape, applied to the glass surface. Lead tape has a high degree of bend memory. That is, when lead tape is bent it tends to stay bent. Bends retained in the lead tape produce visual defects. In this embodiment, the drive roller 110, the pinch roller 118, the pivotal platen 122 and/or the application roller 120 are configured to minimize bending of the tape between the drive roller 110 and the application roller 120.
The pivotal platen 122 separates the liner 15 from the tape 14, as the tape 14 passes over the platen 122. After the liner 15 is separated from the rest of the tape 14, the liner winds around the pinch roller 118 and is taken up by the liner roller 136 (see
The tape 14 includes an adhesive layer 28 and a liner 15 covering the adhesive layer. Examples of tape that can be applied by the disclosed tape head 100 are ACCENTRIM™ tape and lead tape. To start applying the tape to the surface, the tape end 95 is located under the application roller 120. The application roller air cylinder 131 actuates the application roller 120 into contact with the tape 14 and the glass sheet 12. Once the tape 14 is between the application roller 120 and the sheet 12, the adhesive layer bonds the tape 14 to the glass sheet by pressure. These steps are used to initially start applying the first end 95 of the tape 14 to the sheet of glass 12. To continue applying tape 14 to the glass sheet 12, the tape head 100 moves relative to the stationary sheet of glass 12, while the application roller 120 applies the tape 14.
In one embodiment, the tape head 100 is adapted for applying a lead tape 14 having a curved profile to a glass surface. In this embodiment, tape head 100 includes a tape application roller having a circumferential concavity that corresponds to the curved tape profile for pressing the tape to the glass surface. The concavity can be slightly over-cupped as compared to the tape profile to apply more pressure to edges of the curved tape than a central portion of the curved tape. The tape application roller having a circumferential concavity smooths out rippled edges of a tape strip, such as a lead tape strip, and also seals the edges from water penetration.
In one embodiment, the tape head 100 is adapted to apply curved patterns 183 of ductile tape to glass sheets. Referring to
In one embodiment, curved tape segment patterns that are stored in a controller 200 having a memory are automatically applied to a glass surface. The tape head is moved along a path stored in a controller memory. The controller 200 controls the tape head to dispense curved patterns of tape onto the glass surface. This is facilitated by aligning the midpoint of a tape application roller carried by the tape head with an axis of rotation of the tape head.
In the exemplary embodiment, the cutting mechanism is adapted to cut a thick, ductile tape, such as a tape that provides the appearance of leaded glass when applied. The cutting mechanism 116 includes the fixed blade 112, a first linear bearing component 131, a second linear bearing component 133, the linearly moveable blade 114, and the blade actuator 150. In the illustrated embodiment, the a stationary blade 112 is coupled to the frame by a stationary blade bracket 135. The first linear bearing component 131 is also coupled to the frame. The second linear bearing component 133 is coupled to the first linear bearing component 131 such that the second linear bearing component is constrained to linear movement with respect to the first linear bearing component. The moveable blade 114 is connected to the second linear bearing component by a moveable blade bracket 139. The moveable blade 114 is constrained to linear movement with respect to the fixed blade 112. The actuator 150 is coupled to the moveable blade 112 and the frame 114 for moving the moveable blade along a linear path with respect to the fixed blade to cut the lead tape. In the illustrated embodiment, a backing member 141 fixed to the frame is positioned behind the moveable blade bracket 139 to prevent movement of the moveable blade away from the fixed blade. The cutting mechanism provides sufficient clearance and support for wide lead tape strips, such as 18 mm wide lead tape, and allows for easier blade gap setting. The linear bearing arrangement helps maintain alignment of the blade while maintaining the rigidity of the bladeholders.
The cutting mechanism 116 cuts the tape 14 transversely when the air cylinder 150 actuates to force the moveable blade 114 to move along a linear path and contact the fixed blade 112. Referring to
To apply the second end 151 of the tape 14, the tape head 100 continues moving relative to the sheet of glass to allow the application roller 120 to press the remaining tape 14 against the glass sheet 12. The air cylinder 150 moves the moveable blade 114 again to move the moveable blade 114 out of contact with the fixed blade 112. At the same time the moveable blade 114 moves out of contact with the fixed blade 112, the pivotal platen 122 rotates clockwise under the force of the biasing spring to move the platen toward the blades 114, 116 of the cutting mechanism 116, between the blades 114, 116 to allow the tape 14 to pass through the cutting mechanism 120 when the tape advances.
To operate the x-axis actuator 68, y-axis actuator 70, and rotary actuator 72 to move the tape head 100, the station 200 preferably includes a computer processor/controller 300 for sending signals to the actuators 68, 70, 72 to move the tape head 100 relative to the tabletop 52. The computer processor and controller then determines which way to direct the actuators 68, 70, 72 to move the tape head 100 to apply the tape to the glass and to cut the tape. In one embodiment, the computer processor and controller is an “open loop” system, which calculates where the tape head 100 is located on the tabletop 52, based on a known series of moves. For example, the ball screw in either the x-axis actuator 68 or y-axis actuator 70 will move the tape head 100 a known distance per one rotation of the ball screw. If the computer processor knows the initial location of the tape head 100, like the first home position, or the second home position, it can determine the final location of the tape head 100, based on how many rotations the ball screws actually rotated. The computer processor will send a signal to the x-axis and y-axis actuators 68, 70 to turn the ball screws a calculated number of rotations to move the tape head 100 a certain distance in a given direction. The computer processor also sends signals to the rotary actuator 72 to rotate the tape head 100 relative to the z-axis of the tabletop 52. A suitable controller 300 is a controller sold under the trade name Compumotor, which is commercially available from Braas Company located in St. Paul, Minn., sold under part number 6K4. In another embodiment, the computer processor is a “closed loop” system, which calculates where the tape head 100 is at all times on the tabletop 52.
In the exemplary embodiment, the controller is programmed for quick tooling changes. The changeover from one size or type of tape is done with quick release collars. A software offset library is stored in a memory of the controller. The software offset library retains settings that are specific to the set of parts (guide rollers, drive roller, pinch roller, platen, application roller) that correspond to each size/type of tape. As a result, it is not necessary to mechanically alter one set of parts to respond similarly to other sets of parts. The software offset library is used to adjust the application settings of the head 110, to apply different sizes/types of tape in a similar fashion. The controller is also programmed to allow one set of parts to operate in more than one way. For example, the controller is programmed to use the same set of parts to apply a straight tape strip and a curved tape strip.
To determine the initial location of the tape head 100 on the tabletop 52, the actuators 68, 70, 72 preferably include sensors to determine the location. Suitable sensors for the actuators 68, 70, 72 are Prox Sensors sold under the trade name Omron, which is commercially available from Braas Company located in St. Paul, Minn., sold under part number E2E-X1R5E1-M1-N.
In one embodiment, the tape applicator head 100 is coupled to a controller 300 that is adapted to apply aligned decorative patterns 10 to both sides of a glass sheet 12. Applying lead tape strips to both sides of the glass requires that they are directly on top of each other so that the glass appears to have been actually leaded. An offset of the lead strip on the inside and outside surfaces will create a visual defect. If the same home position on the table is used as the reference point, a different corner of the glass sheet will be referenced when the glass sheet is flipped. If the glass size is different than the desired (programmed) size, an offset will occur between the inner and outer lead strips. As described in co-pending application Ser. No. 10/922,741 use of a second home position on the table so that the same corner on the glass sheet is referenced eliminates this chance of error.
Some tape segments are applied through use of the cutter 116 only. These are elongated tape segments with square ends achieved by cutting accross the width of the tape with the cutter to form a perpendicular cut completely through the tape. Other cuts are applied by a rotatably mounted wheel cutter 210 (piazza cutter) mounted to the head 100. This cutter rotates as the head 100 moves in relation to the glass to score the tape after it has been applied onto the surface of the glass. A typical tape application involves laying the tape and then going back to apply cuts with the cutter 210. Once this has been done, the excess tape is removed by an operator who removes the scrap tape segments from the glass.
Additional details regarding the tape application station 200 are contained in commonly assigned co-pending patent application Ser. No. 10/922,741 filed Aug. 20, 2004 entitled “Method and Apparatus for Applying Aligned Tape Patterns” whose subject matter is incorporated herein by reference.
Layering Tape Segments
The patterns 10 depicted in
Of the tape segments shown in
A few comments help explain the process of deciding an order of tape segment application. Generally all segments making up a first set that align in the same direction (are parallel to each other) are applied in sequence before other segments are applied that are aligned at oblique angles with respect to the first set. Hence, the two segments 220, 221 align and are applied as a set. Any overlying segments at oblique angles are also applied in a group. Note, that although the pattern 10 contains overlying segments, it is possible to cut tape after it is dispensed, so that the segments abut rather than overlie closely adjacent segment portions.
The enlarged view in
The enlarged view in
To show why, assume the tape segment 270 is applied first. When the segment 250 is applied, it will overlie the end of the segment 270 as indicated by the dotted line region of overlap in
A pattern 10 depicted in
The 2003/0109946 published application is not concerned with inappropriate cuts nor with controlling which segments overlie others in the finished pattern. It is only concerned with an ability to remove trimmed segments for pieces that lie beneath other pieces.
To overcome the problems encountered with cutting (or trimming) tape after it is laid onto the glass 12 as well as achieving a desired appearance, a concept of tape segment layering is used to define an order of tape application to the glass. Most modern computer aided design (CAD) software supports the concept of layers or layering. A drawing can have components made up of a number of named layers. By assigning tape segments to different layers and converting the layers to machine instruction language based on the order of the layers, it is guaranteed that subsets of tapes that make up the pattern are applied in a specific controlled order. Note, in accordance with an exemplary embodiment of the invention, the order of tape application within a layer is not important and is based on when the tape definition is encountered when the tape data is being interpreted by the controller 300. (See
A tape segment data structure for an elongated straight lead tape portion (such as depicted in
Data having this type structure is transferred in an order of application to the controller 300 by a formatting computer (not shown). The formatting computer may be a networked computer that is coupled to the hardware of the tape application station 200 and also executes, for example, a visual basic program that receives as input a dxf formatted drawing and produces a sequence of data structures such as the listing 1 data structure. The controller 300 responds to receipt of the data structure by moving the head 100 through co-ordinated motor energizations to an appropriate start position, applying a tape segment and performing any needed post application trimming.
If the dxf drawing is not layered, the formatting computer can produce layers but more typically the dxf drawing will be a layered drawing wherein tape segments are contained in layers based on a ‘correct’ order of application of the tape segments to the panel presently at the station 200.
A flow chart 310 of
The drawing layers must be evaluated by the computer in a correct order. This order is evaluated 321 by the visual basic conversion program and as an example is done by an alphabetical ordering of the layer names. A first layer's first tape is identified 322 and all cuts for that tapes designated layer are identified 324 and added to the tape segment data structure (listing 1). That process continues by getting data 325 from other tape segments until it is determined 326 that all tapes in the first layer are formatted. If they have been formatted the process 310 transmits 238 the formatted tapes to the controller. Once all layers have been determined 330 to have been sent to the controller 300, the formatting computer institues a panel transfer away from the station 200 to a next station and loads tape data for the next subsequent panel or sheet that is delivered to the tape application station 200.
Although the present invention has been described with a degree of particularity, it is the intent that the invention include all modifications and alterations falling within the spirit or scope of the appended claims.
