Patent Publication Number: US-8979405-B2

Title: Print preview for printers with multiple print heads

Description:
BACKGROUND 
     This invention relates generally to the field of printing systems, and more particularly to printers in which the print heads do not move during printing operations. 
     For printing applications such as printing out envelopes or letters for large mailings, it may be desirable to print at faster rates than is possible with printers that employ moving print heads. For these applications, high speed printing systems have been developed that employ two or more print heads that are fixed during printing operations. The positions of the print heads may be adjusted during set-up for a print job. 
     Conventional print preview software has not provided satisfactory guidance to users in regard to fixed-head printers. A fixed head printer can only print on the portions of the substrate (e.g., envelope or letter stock) which correspond to the positions of the print heads set for the printing job. But conventional print preview displays fail to take into account the “dead zones” on the substrate resulting from the positioning of the fixed heads. As a result, conventional print preview displays may present a misleading image of the print layout that will actually be produced. For example, a conventional print preview display (or a display provided during composition of a print layout) may show text in a portion of the printing stock profile that cannot be printed on by the print heads as currently positioned. In other words, with conventional print preview displays for fixed-head printers, what you see is not necessarily what you get. Consequently, printing errors may occur in which text appears on the printed items at different locations from those the user desired. This may lead to decreased efficiency, spoiled printing stock, and lost time and effort. 
     SUMMARY 
     Accordingly, an improved printing system and method are provided. The improved system includes a first print head for printing at a first position along a first print axis, a second print head for printing at a second position along a second print axis, a transport mechanism for transporting substrates adjacent the first and second print heads in a direction transverse to the print axes, a control device coupled to the first and second print heads, and a display device coupled to the control device. The control device is operative to control the display device such that the display device displays a representation of a substrate. The control device also controls the display device to display a first printing field at a first location in the representation of the substrate. The first location corresponds to the first position (i.e., the position of the first print head). The control device also controls the display device to display a second printing field at a second location in the representation of the substrate. The second location corresponds to the second position (i.e., the position of the second print head). 
     The printing system may also include a head positioning mechanism that is responsive to the control device and selectively re-positions the first and second print heads along the print axes. 
     The control device may control the display device to display at least one interactive display element. The user of the system may be permitted to interact with the at least one interactive display element to control the head positioning mechanism to adjust the positions of the first and second print heads. 
     The display device may display in the first printing field an indication of at least one type of information to be printed by the first print head and may display in the second printing field an indication of at least one type of information to be printed by the second print head. 
     The representation of the substrate may be in a shape that corresponds to a profile of a mailing envelope. 
     In another aspect, there is provided a method of operating a printing system. The printing system includes a first print head located at a first position along a first print axis and a second print head located at a second position along a second print axis. The method includes displaying a representation of a substrate, displaying a first printing field at a first location in the representation, and displaying a second printing field at a second location in the representation. The first location corresponds to the first position (the position of the first print head) and the second location corresponds to the second position (the position of the second print head). 
     The method may further include displaying an interactive display element, allowing a user of the printing system to interact with the interactive display element to provide user input, and responding to the user input by repositioning at least one of the print heads. The method may also include changing at least one of the first and second locations (the locations of the printing fields) to indicate the repositioning of the print heads. 
     In another aspect a printing system includes a print head that remains in a fixed position during printing operations. The printing system further includes a mechanism for determining the fixed position of the print head. The printing system further includes a display mechanism which is responsive to the mechanism for determining. The display mechanism is for providing a print preview display. The print preview display is indicative of the fixed position of the print head relative to a profile of an item of printing stock to be used in a printing job. 
     As used herein and in the appended claims, “determining” a position of a print head may include one or both of moving the print head to such position or detecting such position. 
     The display mechanism may be part of a user interface, and the printing system may further include a mechanism that is responsive to user input provided via the user interface, such mechanism being for re-positioning the print head prior to the printing job. 
     The printing system may further include a transport mechanism for transporting items of printing stock adjacent the print head. 
     The print head may be one of a plurality of print heads for printing respective items of information on each one of the items of printing stock. The print preview display may be indicative of a respective fixed position of each of the print heads relative to the profile of the item of printing stock. 
     Therefore, it should now be apparent that the invention substantially achieves all the above aspects and advantages. Additional aspects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Various features and embodiments are further described in the following figures, description and claims. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description given below, serve to explain the principles of the invention. As shown throughout the drawings, like reference numerals designate like or corresponding parts. 
         FIG. 1  is block diagram of a printing system provided in accordance with the present invention. 
         FIG. 2  is an example of a screen display image that may be provided by the printing system of  FIG. 1 . 
         FIG. 3  is a flow chart that illustrates a process that may be performed by the printing system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention includes a printing system and a method of operating the printing system. The printing system includes two or more print heads that are fixed during printing operations, but adjustable in position in between printing operations. The printing system provides to an operator of the printing system a print preview screen display that shows where on the substrate (e.g., on the envelope or letter stock) each print head is positioned to print. The print preview screen display may also identify the types of information each print head will print. Thus effectively the print preview screen display provides a “what you see is what you get” display that allows the operator to make any adjustments in print head position that may be needed to obtain exactly the print-out configuration that the operator desires. As a result, the operator may fully control the printing operation and may avoid costly errors in printing. 
     Referring now to the drawings, and particularly to  FIG. 1 , the reference numeral  100  indicates generally a printing system provided in accordance with the present invention. The printing system  100  includes print heads  102 ,  104  which are indicated schematically as functional blocks. The print heads  102 ,  104  are of the so-called “fixed” type in that the print heads do not move during printing operations. Print heads of this type are suitable for use in high-volume printing operations, and the printing system  100  may be suitable for expeditiously handling jobs that require printing of thousands of pieces, such as envelopes, bills and/or letters for a large mailing. 
     Prior to the start of a print job, the print head  102  may be positioned at a first position  106  along a first print axis  108 , and the print head  104  may be positioned at a second position  110  along a second print axis  112 . The print axes  108 ,  112  may be parallel to each other; in some embodiments the print axes may coincide. 
     The printing system  100  may also include a mechanism (represented by block  114 ) which is operative to re-position the print heads along their respective print axes. In addition, or alternatively, the mechanism  114  may be operative to detect the positions of the print heads along the print axes. The print head positioning/position-detection mechanism  114  may include a suitable combination of motors, drive elements such as belts or the like, and/or sensors or encoders, none of which are separately shown. 
     In addition, the printing system  100  may include a substrate transport mechanism  116 . The substrate transport mechanism  116  is operative to transport a sequence of substrates (not shown; may be, e.g., items of letter stock or envelope stock) in a transport path adjacent to the print heads  102 ,  104 . The substrate transport mechanism  116  transports the substrates in a transport direction (indicated by arrow  118 ) which is transverse to the print axes  108 ,  112 . The substrate transport mechanism may provide all of the motion of the substrates relative to the print heads, since as noted before the print heads do not move during printing operations. 
     The printing system may further include a control device  120  which is coupled to the print heads  102 ,  104  and to the print head positioning/position-detection mechanism  114  as well as to the substrate transport mechanism  116 . In some embodiments, the control device  120  may include a conventional microprocessor (not separately shown) and associated memory devices (not separately shown) to serve for working memory and program storage. The control device  120  may control operations of the print head positioning/position detecting mechanism  114  to set the positions of the print heads  102 ,  104  and/or may receive output from the print head positioning/position detecting mechanism which indicates the positions of the print heads  102 ,  104 . In addition, the control device  120  may control operation of the substrate transport mechanism  116  and may control the print heads  102 ,  104  to cause the print heads to print desired information on the substrates transported by the substrate transport mechanism  116 . 
     Still further, the printing system  100  may include a display device  122  which is coupled to and controlled by the control device  120 . The display device may be, for example, a conventional CRT or flat panel display. The printing system may further include user input devices  124  such as a keyboard and a mouse, which are not separately shown. Together with software which programs the control device  120 , the display device  122  and the user input devices  124  may implement a graphical user interface by which the user may control the printing system  100 . 
       FIG. 2  is an example of a “print preview” screen display image that the control device  120  may cause the display device  122  to display in accordance with aspects of the present invention. The display of  FIG. 2  includes a rectangular outline  202  which is a representation of the profile of a substrate (in this example, an envelope) of the type that is to be printed in the printing job that is previewed by the screen display. The screen display also includes a first printing field  204  which is at a location in the representation  202  that indicates where information to be printed by the print head  102  will appear on the envelopes if the print job goes forward as presently configured. Thus the printing field  204  corresponds to the position of the print head  102  along the print axis  108 . Within the first printing field  204  there is displayed alphanumeric information  206  to indicate the type(s) of information to be printed by the print head  102 . (In this example, the information to be printed by the print head  102  is the addressee&#39;s name on a first line and the number and street on a second line.) 
     The screen display also includes a second printing field  208  which is at a location in the representation  202  that indicates where information to be printed by the print head  104  will appear on the envelopes if the print job goes forward as presently configured. The second printing field  208  corresponds to the position of the print head  104  along the print axis  112 . Within the second printing field  208  there is displayed alphanumeric information  210  to indicate the type(s) of information to be printed by the print head  104 . (In this example, the information to be printed by the print head  104  is the city, state and zip code in a single line.) 
     The screen display further includes a first interactive display element  212 . The first interactive display element  212  is positioned to the side of the representation  202  and in alignment with the first printing field  204 . The first interactive display element  212  includes a numeric field  214  and arrow buttons  216 . The numeric field  214  contains numeric information that indicates a Y-direction position of the first printing field  204  in the representation  202 . Correspondingly, the numeric information in numeric field  214  also indicates the position of the print head  102  along the print axis  108  and where along the Y-direction the information to be printed by the print head  102  will appear on the envelopes to be printed in the print job currently being previewed. 
     The screen display further includes a second interactive display element  218 . The second interactive display element  218  is positioned below the first interactive display element  212  and in alignment with the second printing field  208 . The second interactive display element  218  includes a numeric field  220  and arrow buttons  222 . The numeric field  220  contains numeric information that indicates a Y-direction position of the second printing field  208  in the representation  202 . Correspondingly, the numeric information in numeric field  220  also indicates the position of the print head  104  along the print axis  112  and where along the Y-direction the information to be printed by the print head  104  will appear on the envelopes to be printed in the print job currently being previewed. 
     A cursor  224  is shown in numeric field  220  of second interactive display element  218 . The user may operate the user input devices  124  ( FIG. 1 ), e.g., the mouse, to position the cursor  224  in either the numeric field  214  of the first interactive display element  212  or in the numeric field  220  of the second interactive display element  218 . The user may then use the keyboard to directly change the numeric information in the numeric field  214  or the numeric field  220 , as the case may be. Alternatively, the user may manipulate the arrow buttons  216  or  222  to increment or decrement the numeric information in the respective numeric fields. By either or both techniques, the user is allowed to interact with the interactive display elements to change the indicated numeric information. The control device  120  responds to this user input by controlling the print head positioning/position sensing mechanism  114  to re-position the print head  102  or  104 , as the case may be, to reflect the updated position numeric data indicated by the user. 
     In some embodiments, the user may also provide input to re-position one or both of the print heads by “dragging” one or both of the printing fields  204 ,  208  with a pointer/cursor (not shown) controlled by a mouse operated by the user. 
     The display of  FIG. 2  further has a cancel button  226 , a print button  228  and a print_all button  230 . Actuation of the cancel button  226  causes cancellation of the print job being previewed. Actuation of the print button  228  causes the first piece of the print job to be printed. Actuation of the print_all button  230  causes the entire job to be printed. 
       FIG. 3  is a flow chart that illustrates a process that may be performed by the printing system  100 . 
     At  302  in  FIG. 3 , a print job is set up in response to appropriate input from the user. Then, at  304 , the user may elect to have a print preview display, and the control device  120  then controls the display device  122  to display a display screen of the kind illustrated in  FIG. 2 . At  306 , the user may provide input by interacting with one or both of the interactive display elements  212 ,  218 , as described above, and the resulting user input is received by the control device  120 . For example, the user may interact with one or both of the interactive display elements to eliminate the gap  232  between the printing fields  204 ,  208 . As indicated at  308 , the control device  120  then responds to the user input by controlling the print head positioning/position sensing mechanism  114  to adjust the position of one or both of the print heads  102 ,  104  in accordance with the user input. Also, as indicated at  310 , the print preview display may be updated to reflect the user input and the re-positioning of the print heads in response to the user input. That is, the location in the representation  202  of one or both of the printing fields  204 ,  208  may be changed in the display screen to reflect the new position(s) of the print head  102  and/or  104 . 
     When the print preview display is satisfactory to the user, the user may cause the printing job to proceed. 
     With these features, and particularly the print preview display illustrated herein, the system may allow a user to readily detect and correct any difference between the printing configuration desired by the user and the printing configuration that would result from the current positioning of the print heads. This may help the user to avoid errors in setting up print jobs and may provide significant savings in time and effort while avoiding spoilage of printing stock due to errors. 
     In the example system described above there are two print heads, but in other embodiments there may be only one fixed print head, or three or more fixed print heads. From previous discussion it will be appreciated that the print heads may be fixed during printing operations while being adjustable in position before a print job is commenced. 
     The embodiment described above provides for adjustment of print head position by operation of motors and/or other electromechanical devices in response to data input to a control device by a user. In addition or alternatively, the system may allow for direct manual repositioning of print heads by the user. 
     The words “comprise,” “comprises,” “comprising,” “include,” “including,” and “includes” when used in this specification and in the following claims are intended to specify the presence of stated features, elements, integers, components, or steps, but they do not preclude the presence or addition of one or more other features, elements, integers, components, steps, or groups thereof. 
     A number of embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Other variations relating to implementation of the functions described herein can also be implemented. Accordingly, other embodiments are within the scope of the following claims.