Patent Application
20050248644
1. Field of the Invention
The present invention relates to forming perforations in a media, and, more particularly, to a method for enhancing perforation speed.
2. Description of the Related Art
Various devices are available for performing perforation and/or cutting operations. However, many such devices are used in commercial applications, and are generally cost prohibitive to lower volume users. Also, such devices are often standalone devices, requiring the purchase of additional hardware. While some efforts have been directed to incorporating perforation or cutting devices into an imaging device, there still exists a need for a versatile imaging apparatus and associated method that enables low volume users to enjoy the benefits of perforation.
Typically, perforation speeds in such an imaging apparatus are relatively slow. For example, in some such imaging apparatuses the perforation operation may take over three times as long to complete as the printing operation. At least in part, the relatively slow perforation speed is because the imaging apparatus is limited to moving the media in a single media feed direction, e.g., from the media source toward the media exit tray, due to obstructions in the media path or operational characteristics of the of the media pick/media feed mechanism of the imaging apparatus.
The present invention, in one form thereof, is directed to a method for perforating a media using an imaging apparatus having a carriage mounting a perforator and configured for reciprocation along a bi-directional scanning path. The media has a horizontal dimension and a vertical dimension, the bi-directional scanning path being parallel to the horizontal dimension and perpendicular to the vertical dimension. The method includes (a) forming a first set of perforations beginning at a perforation row Rstart and ending at a perforation row Rend vertically spaced from the perforation row Rstart, wherein the media is moved in a first media feed direction substantially perpendicular to the bi-directional scanning path before each successive perforation in the first set of perforations; and (b) feeding the media in a second media feed direction opposite the first media feed direction by a distance D1.
The present invention, in another form thereof, is directed to an imaging apparatus, including a carriage mounting a perforator and configured for reciprocation along a bi-directional scanning path. A feed roller is provided for feeding a media, the media having a horizontal dimension and a vertical dimension, the bi-directional scanning path being parallel to the horizontal dimension and perpendicular to the vertical dimension. A drive unit is coupled to the feed roller for driving the feed roller. A controller is coupled to the carriage, the perforator and the drive unit. The controller executes program instructions for: (a) forming a first set of perforations beginning at a perforation row Rstart and ending at a perforation row Rend vertically spaced from the perforation row Rstart, wherein the media is moved in a first media feed direction substantially perpendicular to the bi-directional scanning path before each successive perforation in the first set of perforations; and (b) feeding the media in a second media feed direction opposite the first media feed direction by a distance D1.
An advantage of the present invention is that the time required to perform perforations is decreased without the necessity of performing a major redesign of the media pick/media feed mechanisms of the imaging apparatus.
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate exemplary embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
Referring now to the drawings and particularly to
Computer 12 is typical of that known in the art, and may include a monitor to display graphics or text, an input device such as a keyboard and/or mouse, a microprocessor and associated memory, such as random access memory (RAM), read only memory (ROM) and a mass storage device, such as CD-ROM or DVD hardware. Resident in the memory of computer 12 is printer driver software. The printer driver software places print data and print commands in a format that can be recognized by inkjet printer 14.
Ink jet printer 14 includes a carrier system 18, a feed roller unit 20, a mid-frame 22, a media source 24, a controller 26 and a perforator maintenance station 28. Carrier system 18, feed roller unit 20, mid-frame 22, media source 24, controller 26 and perforator maintenance station 28 are coupled, e.g., mounted, to an imaging apparatus frame 29.
Media source 24 is configured and arranged to supply from a stack of print media a sheet of print media 30 to feed roller unit 20, which in turn further transports the sheet of print media 30 during a printing operation and/or a perforation operation.
Carrier system 18 includes a carrier 32, i.e., carriage, that is configured with one or more bays, for example bay 32a and bay 32b. Each of bays 32a, 32b is mechanically and electrically configured to mount, carry and facilitate one or more types of cartridges, such as a monochrome printhead cartridge 34a and/or a color printhead cartridge 34b, and/or a perforator cartridge 34c (see
Carriage 32 is guided by a pair of guide members 40. Either, or both, of guide members 40 may be, for example, a guide rod, or a guide tab formed integral with imaging apparatus frame 29. The axes 40a of guide members 40 define a bi-directional scanning path 52 of carriage 32. Carriage 32 is connected to a carrier transport belt 42 that is driven by a carrier motor 44 via a carrier pulley 46. In this manner, carrier motor 44 is drivably coupled to carriage 32 via carrier transport belt 42, although one skilled in the art will recognize that other drive coupling arrangements could be substituted for the example given, such as for example, a worm gear drive. Carrier motor 44 can be, for example, a direct current motor or a stepper motor. Carrier motor 44 has a rotating motor shaft 48 that is attached to carrier pulley 46. Carrier motor 44 is coupled, e.g., electrically connected, to controller 26 via a communications link 50.
Perforator maintenance station 28 includes an abrasive member 51, such as a ceramic material, arranged to receive and sharpen a perforation device, such as for example, a needle or a blade.
At a directive of controller 26, carriage 32 is transported in a controlled manner along bi-directional scanning path 52, via the rotation of carrier pulley 46 imparted by carrier motor 44. During printing, controller 26 controls the movement of carriage 32 so as to cause carriage 32 to move in a controlled reciprocating manner, back and forth along guide members 40. In order to conduct perforator maintenance operations, e.g., sharpening, controller 26 controls the movement of carriage 32 to position printhead carrier in relation to perforator maintenance station 28. The ink jet printheads 38a, 38b, or alternatively perforation forming mechanism 39, are electrically connected to controller 26 via a communications link 54. Controller 26 supplies electrical address and control signals to ink jet printer 14, and in particular, to the ink jetting actuators of ink jet printheads 38a, 38b, to effect the selective ejection of ink from ink jet printheads 38a, 38b, or to perforation forming mechanism 39 to effect the selective actuation of perforation forming mechanism 39.
During a printing operation, the reciprocation of carriage 32 transports ink jet printheads 38a, 38b across the sheet of print media 30 along bi-directional scanning path 52, i.e., a scanning direction, to define a print zone 56 of ink jet printer 14. Bi-directional scanning path 52, also referred to as scanning direction 52, is parallel with axes 40a of guide members 40, and is also commonly known as the horizontal direction. During each scan of carriage 32, the sheet of print media 30 is held stationary by feed roller unit 20. Feed roller unit 20 includes a feed roller 58 and a drive unit 60. The sheet of print media 30 is transported through print zone 56 by the rotation of feed roller 58 of feed roller unit 20. A rotation of feed roller 58 is effected by drive unit 60. Drive unit 60 is electrically connected to controller 26 via a communications link 62.
Perforation forming mechanism 39 includes at least one perforation device 66, which may include one or more needles or blades used in forming perforations in the sheet of print media 30.
Referring now to
During a perforation operation, the reciprocation of carriage 32 transports perforator cartridge 34c, including perforation forming mechanism 39, across the sheet of print media 30 along bi-directional scanning path 52, i.e., a scanning direction, to define a perforation zone corresponding to print zone 56 of ink jet printer 14, and for convenience will also be referred to using the element number 56, i.e., perforation zone 56. The sheet of print media 30 is transported in print media feed direction 72 through perforation zone 56 by the rotation of feed roller 58 of feed roller unit 20.
Accordingly, in one embodiment, where perforation forming mechanism 39 has only a single perforation device 66, e.g., a single needle, then the maximum vertical perforation resolution (i.e., in a direction perpendicular to bi-directional scanning path 52, e.g., in print media feed direction 72) is limited to the minimum indexing distance of feed roller 58, while the horizontal perforation resolution (parallel to bi-directional scanning path 52) may be controlled to be as high as the horizontal printing resolution of printheads 38a, 38b, or lower. However, the extent of each perforation formed in the sheet of print media 30 may be increased by using a blade as perforation device 66. As used herein, the term perforation resolution refers to the maximum number of perforation holes in a given distance of the media, such as perforations per inch (ppi).
In another embodiment, where perforation forming mechanism 39 has multiple perforation devices 66, e.g., multiple needles or blades, arranged in a column in the print media feed direction 72, then the maximum vertical perforation resolution and the horizontal perforation resolution may be controlled to be a high as the printing resolution of printheads 38a, 38b, or lower.
Controller 26 is communicatively coupled to perforation forming mechanism 39 via communications link 54 and electrical interface 64 of perforation cartridge 34c. Controller 26 is configured, via hardware, firmware or software, to select either or both of the vertical perforation resolution and the horizontal perforation resolution. Such a selection may be based, for example, on media type (e.g., plain paper, photo paper, stickers, plastic, etc.), media thickness, or a resolution selected by a user. Alternatively, the perforation resolution may be established by computer 12, with perforation resolution commands or data being sent from computer 12 to controller 26.
Motor 76 includes a shaft 92 connected to flywheel 80. Linkage 82 is pivotably coupled to each of flywheel 80 and perforation device 66. Guide bushing 83 establishes an orientation of perforation device 66, and provides a low friction inner guide surface that contacts perforation device 66. Also, the bottom surface of guide bushing 83 will release perforation device 66 from the sheet of print media 30 as the perforation device 66 is retracted into guide bushing 83, if the sheet of print media 30 become stuck to perforation device 66 during perforation.
A stroke of perforation device 66 may be established based on the location on flywheel 80 where linkage 82 is pivotably attached. As shown, a full rotation of flywheel 80, such as in the clockwise direction 94 as shown, will result in a full cycle of perforation device 66, e.g., from the fully retracted position to the fully extended position, and back to the fully retracted position. Alternatively, a full cycle of perforation device 66 may be performed, for example, by a clockwise half-rotation of flywheel 80 to extend perforation device 66 from the fully retracted position to the fully extended position, followed by a return counter-clockwise half-rotation to return perforation device 66 from the fully extended position to the fully retracted position. As a further alternative, by stopping the rotation of flywheel 80 before perforation device 66 has reached its fully extended position, the distance D that perforation device 66 extends through the sheet of print media 30 (see
Sensor 78 senses a position of flywheel 80, such as a position indicia or feature representing a home (fully retracted) position. Alternatively, the position indicia, or feature, can be located near the home position, but not at the home position, such that sensor 78 is tripped just before flywheel 80 is at its home position. Also, it is contemplated that multiple position indicia or features may be established around flywheel 80, thereby providing a finer detection of the position of perforation device 66, and in turn, enabling better control over the position of perforation device 66. Such a position indicia or feature may be formed from a material having contrasting characteristics to that of the remainder of flywheel 80. For example, flywheel 80 may have a highly reflective finish except for the position indicia or feature, which has a light absorbing finish. Thus, sensor 78 supplies a signal to control circuit 74 so as to stop rotation of shaft 92 of motor 76, and in turn stop the rotation of flywheel 80, when sensor 78 senses the position indicia or feature on flywheel 80.
Biasing spring 84 is pivotably coupled to flywheel 80, and is located to aid the retention of flywheel 80 in the home position, and in turn, to aid the retention of perforation device 66 in its home (fully retracted) position.
Shaft 92 of motor 76 connected to cam 96. Cam follower 98 is coupled, e.g., connected to or integral with, perforation device 66. Guide bushing 83 establishes an orientation of perforation device 66, and provides a low friction inner guide surface that contacts perforation device 66. A stroke of perforation device 66 may be established based on the location of a cam lobe 102 on cam 96 in relation to cam follower 98. As shown, a full rotation of cam 96, such as in the clockwise direction 94 as shown, will result in a full cycle of perforation device 66, e.g., from the fully retracted position to the fully extended position, and back to the fully retracted position. Alternatively, a full cycle of perforation device 66 may be performed, for example, by a clockwise half-rotation of cam 96 to extend perforation device 66 from the fully retracted position to the fully extended position, followed by a return counter-clockwise half-rotation that returns perforation device 66 from the fully extended position to the fully retracted position. As a further alternative, by stopping the rotation of cam 96 before perforation device 66 has reached its fully extended position, the distance D that perforation device 66 extends through the sheet of print media 30 can be selectably controlled. Such control can be effected, for example, by configuring controller 26 to select distance D and control the stroke of perforation device 66 accordingly.
Sensor 78 senses a position of cam 96, such as a position indicia or feature representing a home (fully retracted) position. Such a position indicia or feature may be formed from a material having contrasting characteristics to that of the remainder of cam 96. For example, cam 96 may have a highly reflective finish except for the position indicia or feature, which has a light absorbing finish. Thus, sensor 78 supplies a signal to control circuit 74 so as to stop rotation of shaft 92 of motor 76, and in turn stop the rotation of cam 96, when sensor 78 senses the position indicia or feature on cam 96.
Spring 100 is positioned between cam follower 98 and guide bushing 83 to aid in biasing perforation device 66 in its home (fully retracted) position.
Armature 106 is displaced linearly upon the actuation of solenoid 104. Armature 106 is coupled, e.g., connected to or integral with, perforation device 66. Guide bushing 83 establishes an orientation of perforation device 66, and provides a low friction inner guide surface that contacts perforation device 66. A full cycle of perforation device 66 may be established based on the actuation of solenoid 104 to move perforation device 66 from the fully retracted position to the fully extended position, followed by the de-actuation of solenoid 104 to move perforation device 66 with the biasing aid of spring 100 back to the fully retracted position.
Sensor 78 senses a position of armature 106, such as a position indicia or feature representing a home (fully retracted) position. Such a position indicia or feature may be formed from a material having contrasting characteristics to that of the remainder of armature 106. For example, armature 106 may have a highly reflective finish except for the position indicia or feature, which has a light absorbing finish. Thus, sensor 78 supplies a signal to control circuit 74 to indicate when sensor 78 senses the position indicia or feature on armature 106.
In the various embodiments of
Alternatively, as shown in
Referring now to
Alternatively, as shown in the breakout section 138, the perforation forming mechanism in perforator carriage 134 may be driven by a perforation drive system 140. Perforation drive system 140 includes a motor 142 having a shaft 144 to which a gear 146 is attached. A second gear 148 is attached to one of the guide members 40. This particular guide member may be a guide rod having a D-shaped cross section, which when rotated emulates the operation of cam 96 of
In this embodiment, controller 26 provides perforation commands to motor 142, which responds by rotating D-shaped guide member 40, which drives the perforation forming mechanism in perforator carriage 134, which in turn causes perforation device 66 to extend from its home position to its perforation position. Further rotation of D-shaped guide member 40 results in perforation device 66 returning to its retracted (home) position, wherein sensor 150 provides a signal to controller 26 to turn off motor 142 to stop rotation of D-shaped guide member 40.
The discussion that follows is directed to describing various methods of the invention. Referring to the embodiment of
At step S200, graphics data is generated, such as by computer 12 executing a graphics application. Such graphics data may represent, for example, image 160 shown in
At step S202, a non-printed color is defined to represent perforation locations.
In one exemplary implementation, the non-printed color may be identifiable by its presence with a predefined sequence of colors. For example, the occurrence of a predefined sequence of two or more colors indicate that the color proceeding, or alternatively following, the predefined sequence is a non-printed color, e.g., the perforation color, which in turn is used to identify perforation locations in the graphics data. For example, the printer driver operating on computer 12, or alternatively imaging apparatus 14, can be programmed to identify the color sequence in the print data and in turn identify the perforation color used to signify a perforation location. Colors may be repeated in the sequence.
As an example, it is predefined that a three pixel color group, beginning with a two color sequence will be followed by the non-printed color, i.e., the perforation color. The three color group may be, for example, a sequence of a yellow pixel and a light gray pixel, followed by a dark gray pixel as the perforation color. When the printer driver operating on computer 12, or alternatively a routine operating in imaging apparatus 14, detects the yellow-light gray sequence of pixels, then the following pixel, e.g., a dark gray pixel, is interpreted and saved, for example in memory associated with computer 12 or controller 26, as a non-printed colorl to be used as a perforation location identifier. Thereafter, each time the printer driver operating on computer 12, or alternatively imaging apparatus 14, detects a dark gray pixel, the dark gray pixel is identified as a non-printed color and its location by definition is a perforation location which will receive a perforation.
In the present embodiment, the term non-printed color is used to indicate the absence of color at the perforation location after perforation, and thus, not only covers the condition where the perforation location does not receive ink during a printing operation since the perforation will eliminate the material in the sheet of print media 30 at the perforation location, but is intended to also cover the condition wherein the perforation color is first printed, and then removed by the perforation.
In another exemplary implementation, computer 12 may analyze the color data associated with the graphics data, and select a color as the non-printed color that is absent with respect to the graphics data. The non-printed color would still be identified based on the color sequence method described above.
At step S204, the non-printed color is embedded in the graphics data for a current perforation job. Based on boundary information, computer 12, executing a program such as in the printer driver, automatically inserts the predefined color sequence proceeded (or alternatively followed) by the non-printed color, i.e., perforation color, into the graphics data, preferably near the beginning of the graphics data, and then embeds the non-printed color at locations corresponding to the perforation boundary specified by the user.
In one implementation, a boundary detection algorithm may be used to automatically identify the perforation boundary of an image. The boundary detection algorithm may be incorporated, for example, into the printer driver, or may be incorporated into firmware in controller 26. The pseudo code for an exemplary boundary detection algorithm is attached in Appendix A. The pseudo code is in the form of a C++ code snippet that demonstrates how a recursive flood fill algorithm can be used to find the edges of an image.
If desired, a halo can be drawn around boundary 162 by replacing each edge pixel with a 3×3 block of pixels centered on the original pixel, and then processing the resulting image with the boundary detection algorithm of Appendix A.
Those skilled in the art will recognize that in practicing the present invention other edge detection algorithms well known in the art could be adapted for substitution for the boundary algorithm represented in Appendix A.
In the present implementation, once boundary 162 of image 160 is identified from the graphics data, a plurality of perforation locations may be assigned to the boundary, at a predetermined default perforation resolution, such as for example 100 ppi, which may later be adjusted.
Alternatively, a polygonal perforation perimeter may be defined to surround boundary 162, at a predetermined perforation resolution, wherein a plurality of perforation locations may be assigned to the polygonal perforation perimeter. For example, a polygonal perforation perimeter 164, such as a rectangle, may be defined to intersects boundary 162 of image 160 represented in the graphics data at least at one perforation location of the plurality of perforation locations. As another example, the plurality of perforation locations are associated with a polygonal perforation perimeter 166, such as a rectangle, that surrounds boundary 162 of image 160, but does not intersect boundary 162 of image 160.
For example, a rectangular perforation perimeter may be determined by electronically scanning the data representing image 160 (
In another implementation, the embedding may be performed, for example, by perforation software running on computer 12, wherein a user selects a perforation boundary around the image to receive perforations. Such a perforation boundary might be entered, for example, by tracing a light pen around image 160 as presented on the monitor of computer 12, or by entering data points from a keyboard.
Further, as an alternative in the above implementations, it is contemplated that perforation coordinates could be supplied to imaging apparatus 14 via a data packet that accompanies each print job sent to imaging apparatus 14.
At step S206, an identifier is provided for identifying the non-printed color in the graphics data. In particular, at step S206, as mentioned above, software operating on computer 12, such as in the printer driver, automatically embeds the identifier as a predefined color sequence proceeded (or alternatively followed) by the non-printed color, i.e., perforation color, into the graphics data, preferably near the beginning of the graphics data to identity to the graphics data reader which color of a plurality of possible colors serves as the non-printed color, i.e., the perforation color for this perforation job.
At step S208, the graphics data, including the non-printed color, is read, for example, by imaging (perforation) apparatus 14.
At step S210, using the identifier, a plurality of perforation locations are identified by apparatus 14 based on the non-printed color.
At step S212, parameters of the perforation apparatus 14 are adjusted in accordance with the current perforation job.
In one implementation of the invention, the adjusting step may include the step of adjusting a perforation density, e.g., perforations per inch (ppi) of the plurality of perforation locations. The perforation density may be dependent on at least one of a print mode, e.g. draft, normal, etc., a media type and a media thickness of the sheet of print media 30. In addition, by setting the perforation density to a value wherein the perforations, i.e., holes, overlap, then a cut is made.
For example, a plain paper sheet may require less perforation per unit length than a photo paper sheet in order to achieve and acceptable punch-out of the perforated item from the surrounding scrap. Accordingly, for example, plain paper may be perforated at 30 ppi, whereas a photo paper sheet may be perforated at 40 ppi.
As another example, a thin media may require less perforation per unit length than a thick media in order to achieve and acceptable punch-out of the perforated item from the surrounding scrap. Accordingly, for example, thin paper may be perforated at 20 ppi, whereas as poster board may be perforated at 45 ppi.
In another implementation of the invention, the adjusting step may include the step of adjusting a perforation speed of forming the perforations at the plurality of perforation locations. The perforation speed may be adjusted, for example, based on factors such as media type, media thickness, and perforation resolution.
In another implementation of the invention, the adjusting step may include the step of adjusting a perforation force of perforation device 66 that forms the perforations. The perforation force may be determined, for example, by monitoring a motor torque of a motor, e.g., motor 44 of
The motor torque is related to the current drawn by motor 44, 142. Thus, by monitoring the motor current, such as through a simple voltage divider circuit well known in the art, the motor current can be determined, and in turn, the perforation force. Accordingly, the perforation force may then be adjusted automatically to a desired force by adjusting the motor torque. As an example, the perforation force adjustment operation may be performed during a perforation of the sheet of print media sheet at a first perforation location occurrence of the plurality of perforation locations, so that subsequent perforations are formed with the proper perforation force. The motor torque can also be used in setting the perforation density and perforation speed
At step S214, the perforation of the sheet of media 30 is performed in accordance with the identifying and adjusting steps, set forth above. The actual perforation may be carried out by perforation system 10, as embodied in one of
Such combined printing and perforating can be performed sequentially, or can be performed simultaneously, in a given printing swath with system 10 in either of the embodiments of
The method of
Imaging apparatus 14 includes carrier system 18 configured to carry a printhead, such as for example, either or both of monochrome printhead 38a and color printhead 38b, and is configured to carry a perforation forming mechanism, such as perforation forming mechanism 39. In the example that follows, for simplicity, reference will only be made to color printhead 38b. During printing, printhead 38b is traced over the sheet of print media 30, wherein the area traced by the printhead defines a print swath having a swath height equal to the spacing between the uppermost and lowermost ink jetting nozzles in printhead 38b. Typically, the sheet of print media is incrementally advanced by feed roller 58 prior to printhead 38b tracing the next print swath. Such concepts are well known in the art. A control unit, which may include the printer driver operating on computer 12 and controller 26 of imaging apparatus, is coupled to printhead 38b and to perforation forming mechanism 39.
The control unit is configured to perform the steps set forth in
At step S250, graphics data is formatted into a plurality of print swaths for printing by printhead 38b.
At step S252, perforation coordinates defining a plurality of perforation locations are associated with the plurality of print swaths, for perforation by perforation forming mechanism 39.
At step S254, it is determined whether a first print swath of the plurality of print swaths includes any perforation locations.
At step S256, at least one of the printing and perforating operations are performed at the first print swath.
At step S258, the sheet of print media 30 is incrementally advanced by feed roller 58 by a predetermined distance less than a height of printhead 38b.
At step S260, it is determined whether a next print swath of the plurality of print swaths includes any perforation locations.
At step S262, at least one of the printing and the perforating are performed at the next print swath.
The control unit is further configured to repeat the steps S258, S260 and S262 until the sheet of print media 30 is completely processed.
The method for forming perforations in a sheet of media, as illustrated in the flowchart of
At step S300, an image, such as image 160 of
At step S302, a plurality of perforation locations associated with the graphics data is identified to perforation apparatus 182 for a current perforation job. Step S302 may be performed, for example, by utilizing the method steps S202, S204, S206, S208 and S210 of
At step S304, parameters of perforation apparatus 182 are adjusted in accordance with the current perforation job. The parameter adjustment of step S304 may be performed, for example, in a manner as described above in step S212 of
At step S306, perforation of the sheet of media 30 is performed in accordance with identifying step S302 and adjusting step S304. Along with performing the perforation, the graphics data may be printed as an image on the sheet of media 30. Such combined printing and perforating can be performed sequentially, or can be performed simultaneously, in a given printing swath with system 10 in either of the embodiments of
At step S400, a plurality of perforation regions associated with a shape of an object to be perforated is identified. For example, there is shown in
At step S402, a perforation density of the plurality of perforation regions is adjusted in accordance with the shape of object 190. In accordance with the present invention, it is contemplated that two or more perforation densities may be used to perforate the same object. For example, a first perforation density may be selected for straight perforation regions 192, a second perforation density may be selected for curved perforation regions 194, and a third perforation density may be selected for discontinuous perforation regions 196. Preferably, in this embodiment, the perforation density selected for curved perforation regions 194 is greater than the perforation density selected for straight perforation region 192. Also, the perforation density selected for discontinuous perforation regions 196 is greater than the perforation density selected for straight perforation region 192.
For example, in order to facilitate the removal of object 190 from the surrounding material 198, the perforation density selected for curved perforation regions 194 and/or discontinuous perforation regions 196 may be set to a value, for example, of 75 to 80 perforations per inch, so as to significantly weaken the connection between object 190 and the surrounding material 198 in the curved perforation regions 194 and/or discontinuous perforation regions 196. However, the perforation density for straight perforation regions 192 may be set, for example, at 30 to 40 perforations per inch so as to retain enough material between adjacent perforation holes to maintain the integrity of the sheet of media 188 during the perforation process, i.e., to prevent premature removal of object 190 from the surrounding material 198, which could result in a paper jam in the perforation system, such as for example, perforation system 10 including perforation forming mechanism 39.
As another example, the perforation density selected for curved perforation regions 194 and/or discontinuous perforation regions 196 may be set to a value, for example, of greater than 80 perforations per inch, wherein the perforations, i.e., holes, overlap so as to form a cut. However, the perforation density for straight perforation regions 192 may be set, for example, at 40 perforations per inch so as to maintain the integrity of the sheet of media 188 during the perforation process, i.e., to prevent premature removal of object 190 from the surrounding material 198, which could result in a jam of the perforation system, such as for example, perforation system 10.
At step S404, the perforation of sheet of media 188 is performed by perforation forming mechanism 39, for example, in accordance with steps S400 and S402. If perforation forming mechanism 39 is moved over the sheet of media 188 at a constant speed, then the perforation density may be controlled by varying the rotational speed of perforation motor 76. For example, if perforation forming mechanism 39 is moved over the sheet of media 188 at a constant speed, then an increase in the rotational speed of perforation motor 76 will result in a higher perforation density, and a decrease in the rotational speed of perforation motor 76 will result in a lower perforation density. The concepts set for above may be applied in a perforation system where the media, such as the sheet of media 188, is transported in a single direction, or in a perforation system where the media is transported bi-directionally, e.g., in a reciprocating manner under perforation forming mechanism 39. In a system where the media is transported bi-directionally, drive unit 60 will be configured to rotate feed roller 58 in both forward and reverse directions.
Another aspect of the present invention will now be described with respect to
In
In order to differentiate between objects 202, 203, 204 to be perforated or cut, and the line 206; text 208, 210; and logo 212 that are not to be perforated or cut, the current aspect of the present invention utilizes a method, as described below with respect to the flowchart of
In the description that follows, the term “cut path” will be used to describe a path associated with a continuous cut or a set of spaced perforations, which identifies, for example, the outer boundary of the object to be removed from the surrounding material of the media. This cut path may be virtual, i.e., defined only in the processor processing the data relating to the cut path, as opposed to displaying or printing the cut path on a visually perceptible medium, e.g., a computer screen or a sheet of print media.
Accordingly,
At step S500, at least one cut path is defined that is related to an object to be separated from said media. Each cut path may be defined by assigning cut path data to the respective cut path, wherein each pixel of the cut path data is set to a predefined state. For example, as shown in
At step S502, a characteristic of each cut path is determined. The characteristic may be, for example, a pixel density within a predefined area. The predefined area may be, for example, bounded by each cut path, and thus, each predefined area may be associated with a corresponding cut path. Thus, in the example shown in
At step S504, the result of the determination made at step S502 is compared to a rejection criteria. The rejection criteria may be, for example, a threshold corresponding to a maximum pixel density within a predefined area. Thus, for example, the pixel density for the predefined area as determined in step S502 is compared to the threshold to determine whether the rejection criteria has been met.
At step S506, it is determined whether a current cut path meets the rejection criteria. If the determination at step S506 is NO, then the process proceeds to step S508 wherein the current cut path is designated as a path to be cut. Such a designation may be in the form of an assignment of a particular color to the cut path designated to be cut. If the determination at step S506 is YES, then the process proceeds to step S510 wherein the current cut path is designated as a path not to be cut.
An exemplary pseudo code for performing steps S500-S506 is attached in Appendix B. In the pseudo code, it is assumed that in a rectangular array of pixels, each pixel can have multiple values, such as for example, a value representing a cut path or a value representing background.
Referring to
Following steps S508 and S510, at step S512 it is determined whether all cut paths have been considered. If the determination at step S512 is NO, then the process proceeds to step S514 to select the next cut path to be considered, and the process returns to step S506. If the determination at step S512 is YES, then the process proceeds to step S516 wherein the cut paths designated in step S508 to be cut are cut.
Accordingly, at step S516, the cut paths designated in step S508 to be cut are cut to facilitate separation of the object from the surrounding material of the media. Cutting may be achieved by performing a continuous cut in the media along the cut path, such as for example, by overlapping perforations, by a blade cut or by a laser beam cut. Also, cutting may be achieved by forming spaced perforation holes in the media along the cut path designated to be cut.
Recall that, as shown in
Referring also to
As shown in
At step S600, lower edge 232 is perforated by scanning perforator 34c along bi-directional scanning direction 52, i.e., horizontally, with respect to media 30.
At step S602, media 30 is advanced in forward media feed direction 72 to perforation row Rstart to being a vertical perforation pass P1.
At step S604, a first set of vertical perforations 240 beginning at perforation row Rstart and ending at a perforation row Rend vertically spaced from the perforation row Rstart is formed. In
Media 30 is advanced in a forward media feed direction 72 substantially perpendicular to bi-directional scanning path 52 before each successive perforation in the first set of vertical perforations 240.
At step S606, media 30 is fed in reverse media feed direction 226 by a distance D1. A maximum amount D1max of distance D1 may be determined based on operational characteristics of a media pick mechanism and a media feed mechanism of imaging apparatus 14. Referring again to
Accordingly, distance D1max also defines the maximum length of the first set of vertical perforations 240, i.e., the distance from the starting perforation row Rstart to the ending perforation row Rend in a perforation pass.
As a supplemental consideration, if imaging apparatus 14 includes a media pick mechanism, such as media pick mechanism 244 shown in
At step S608, a second set of vertical perforations 248 is formed, wherein media 30 is advanced in forward media feed direction 72 before each successive perforation in the second set of vertical perforations 248. Distance D1 may be selected so that the second set of vertical perforations 248 begins at perforation row Rstart of the current perforation pass. As shown in
In some embodiments, for example, the number of perforations in the second set of vertical perforations 248 may equal the number of perforations in the first set of vertical perforations 240, and accordingly, like the first set of vertical perforations 240, the completion of the second set of vertical perforations 248 may occur at perforation row Rend for the current perforation pass.
Thus, the performing of steps S604, S606 and S608 result in the completion of a perforation pass, e.g., perforation pass P1, as illustrated in
Those skilled in the art will recognize that the order of steps S604 and S606, and/or the direction of vertical perforation, may be reversed, if desired.
At step S610, it is determined whether there is a next perforation pass Pn.
If the determination at step S610 is YES, then at step S612 the media 30 is advanced in forward media feed direction 72, and perforator 34c is returned to left edge 234 to position perforator 34c at a next vertical perforation position following perforation row Rend of the first perforation pass P1, and the process returns to step S604, and steps S604, S606 and S608 are repeated to perform next perforation pass Pn for rows Rstart and Rend of next perforation pass Pn. Accordingly, steps S604, S606, S608, S610 and S612 are repeated until the perforating of media 30 is completed. Thus, each perforation pass of the plurality of perforation passes includes the completion of forming the first set of vertical perforations 240, feeding media 30 in reverse media feed direction 226 by a distance D1, and forming the second set of vertical perforations 248.
Of course, printing may occur concurrently with perforating. For example, the present method supports performing at least one printing pass with ink jet printhead 38b between consecutive perforation passes, either before, during or after advancing media 30 in forward media feed direction 72 between the consecutive perforation passes. The number of perforation passes may be, for example, an integer number of times per the number of print passes.
Where a plurality of perforation passes are used to complete perforating of media 30, distance D1 may be varied during at least some of the plurality of perforation passes to reduce printing defects during printing, such as for example, dry time banding.
During perforating using multiple perforation passes, as described above, perforator 34c must be accurately positioned at the desired horizontal position with respect to media 30, such as for example, so as to form a straight vertical line for the left and right edges 234, 236 of the 4×6 inch object 228. Accordingly, in one embodiment of the present invention carriage 32 is transported along bi-directional scanning path 52 to a fixed horizontal position while being under the control of a closed loop control loop, such as a proportional control loop. The closed loop control loop may be implemented, at least in part, in controller 26 in conjunction with horizontal position feedback of perforator 34c along bi-directional scanning path 52.
If the determination at step S610 is NO, then perforation is complete, and the process proceeds to step S614.
At step S614, it is determined whether printing is to continue following the conclusion of perforating.
If the determination at step S614 is YES, then at step S616 the reversal distance, i.e., distance D1, is gradually reduced after the perforating of media 30 is completed while printing on media 30 is continued. Accordingly, a smooth transition is provided between the bi-directional media feed used during perforating and the desired unidirectional media feed when only printing is being performed.
If the determination at step S614 is NO, then the perforating and printing operations are complete.
In embodiments where both perforating and printing are performed during the processing of a sheet of media, it may be desired that the final media move prior to resumption of printing be in forward media feed direction 72 so as to reduce errors caused by hysteresis in the media feed system, e.g., feed roller unit 20. For example, when the prior move for perforating is in reverse media feed direction 226, the distance D1 that the media travels in reverse media feed direction 226 may be supplemented, e.g., increased, to accommodate an additional media feed in forward media feed direction 72 prior to the resumption of printing.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
This is a continuation-in-part of U.S. patent application Ser. No. 10/878,927, filed Jun. 28, 2004, which is a continuation-in-part of U.S. patent application Ser. No. 10/612,771, filed Jul. 2, 2003.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10878927 | Jun 2004 | US |
| Child | 11168625 | Jun 2005 | US |
| Parent | 10612771 | Jul 2003 | US |
| Child | 10878927 | Jun 2004 | US |
