BACKGROUND OF THE INVENTION
1. Field of the invention
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The present invention relates to a printer configured to deposit stacks of printed print media in multiple output stackers, the printer comprising a print controller comprising a print job queue comprising print jobs to be printed. The printed print media to be deposited in the multiple output stackers may be for example sheets of paper or plastic.
2. Description of Background Art
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Printers with multiple output stackers are usually driven in a system mode wherein the print controller determines the output stacker for a print job according to the stacker allocation algorithm installed at the print controller.
SUMMARY OF THE INVENTION
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It is an object of the invention to provide a printer which supports the operator in optimizing the allocation of an output stacker for depositing the sheets of the print job.
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In accordance with the present invention, each print job comprises a first print job property which is an indication of a output stacker for depositing printed sheets of the print job, and the print controller comprises at least one stacker allocation algorithm for automatically allocating an output stacker for depositing the printed sheets of the print job, wherein one of the at least one stacker allocation algorithm is determined to be a default stacker allocation algorithm, and wherein the print controller is configured to deposit the printed sheets of the print job to the output stacker indicated by a non-empty value of the first print job property and to deposit the printed sheets of the print job to the output stacker allocated by the default stacker allocation algorithm when the first print job property has no value.
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By doing so, the printer is able to control deposition of the sheets of print jobs on different stacks in a multi-output location stacker system purely based on the print job themselves and without the need to explicitly indicate an exact location for all print jobs. For example, it is possible to position print jobs on individually requested stacks. The operator is allowed to have full control over job locations from only job settings (no system level change needed) and still not forcing to indicate for every job to which exact stacker the print job needs to be output. Thereby, the object of the present invention has been achieved.
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According to an embodiment the non-empty value of the first print job property indicates a specific output stacker of the multiple output stackers of the printer.
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According to an embodiment the print controller comprises a collection of stacker allocation algorithms and the non-empty value of the first print job property indicates a stacker allocation algorithm out of the collection.
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According to an embodiment the multiple output stackers are sequenced in a sequence and one stacker allocation algorithm out of the collection is configured to select an output stacker which is first in the sequence that still has enough room to fit the printed sheets of the print job on.
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According to an embodiment the multiple output stackers are sequenced in a sequence and one stacker allocation algorithm out of the collection is configured to select an output stacker which is first in sequence which content plus the printed sheets of the print job do not exceed a predetermined height or weight.
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According to an embodiment the multiple output stackers are sequenced in a sequence and one stacker allocation algorithm out of the collection is configured to select an output stacker which is first in the sequence that is empty.
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According to an embodiment the multiple output stackers are sequenced in a sequence and one stacker allocation algorithm out of the collection is configured to select an output stacker which is closest to the print engine.
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According to an embodiment the multiple output stackers are sequenced in a sequence and one stacker allocation algorithm out of the collection is configured to select an output stacker which is farthest from the print engine.
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According to an embodiment a stacker allocation algorithm is a combination of at least two other stacker allocation algorithms from the collection by means of a Boolean construction.
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The present invention also relates to a method for a printer according to the present invention, wherein the method comprises the steps of
- receiving a print job in the print job queue of the printer,
- the print controller reading a value of the first print job property,
- if the first print job property has a non-empty value, the print controller determining the output stacker for the printed sheets of the print job to be the output stacker according to the non-empty value of the first print job property,
- if the first print job property has an empty value, the print controller determining the output stacker for the printed sheets of the print job to be an output stacker allocated by a default stacker allocation algorithm.
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According to an embodiment the non-empty value of the first print job property indicates a specific output stacker of the multiple output stackers of the printer.
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According to an embodiment the print controller comprises a collection of stacker allocation algorithms and the non-empty value of the first print job property indicates a stacker allocation algorithm out of the collection.
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The present invention also relates to a non-transitory software medium comprising executable program code configured to, when executed on a print controller of a printer, enable the print controller to perform the steps of the method according to the present invention.
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The present invention also relates to a non-transitory software medium comprising executable program code configured to, when executed on a print controller of a printer, enable the print controller to perform the steps of the method according to the present invention.
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Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
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The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
- Fig. 1
- is a schematic cross-sectional, side view of a representative example of a printer according to the present invention;
- Fig. 2
- is a flow diagram of an allocation method according to the prior art;
- Fig. 3
- is a flow diagram of an allocation method according to the present invention;
- Fig. 4
- is an example of a representation of a print job queue according to the present invention;
- Fig. 5-6
- are outputs of deposition according to the prior art based on the example in Fig. 4;
- Fig. 7
- is output of deposition according to the present invention based on the example in Fig. 4; and
- Fig. 8
- is a schematic diagram of a computer readable medium according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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The present invention will now be described with reference to the accompanying drawings, wherein the same reference numerals have been used to identify the same or similar elements throughout the several views.
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As is shown in Fig. 1, a printer 1 that is described here as a representative example comprises an input section 10, a main body 12, and an output section 14. The main body 12 comprises a print station 16, a sheet supply system including a sheet transport path 18, an electronic controller 20 and a user interface 22.
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The controller 20 may be formed by a computer, a server or a workstation and is connected to all the functional components of the printer for controlling the same and is further connected to the user interface 22 and to a network 24 via which the controller may communicate with a remote workstation 26 of a user or operator. In an alternative embodiment, the controller 20 may also be installed outside of the main body 12 for controlling the various system components via the network 24.
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The hardware and/or the software of the controller 20 includes among others a print job receiving section 28, a scheduler 30, a feed control section 32, a print control section 34, an output control section 36, and a sheet manager 38. The print job receiving section 28 is arranged to receive, e.g. via the network 24, print jobs each of which includes image data for one or more pages to be printed as well as various job settings. Optionally, the image data may also be received from a local scanner whereas the job settings are input at the user interface 22. The job settings include among others instructions that specify for each image to be printed the properties or type of a recording medium on which the image shall be printed. The job settings also comprise a setting for indicating the output stacker in which the printed sheets of the print job are desired to be deposited.
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The input section 10 includes a plurality of holders 40 each of which accommodates a supply, e.g. a stack, of media sheets of a certain media type. The media types in the different holders 40 may differ in sheet thickness, sheet material, surface properties of the sheets and the like. The input section 10 further includes a feed mechanism 42 arranged to separate individual sheets from a selected one of the holders 40 and to supply them one by one into the sheet transport path 18 under the control of the feed control section 32.
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When the job receiving section 28 has received a print job, the scheduler 30 determines a sequence in which the images of this print job shall be printed. The scheduler 30 further has access to a database that stores the media types and properties of the sheets accommodated in the various holders 40. Based on the job settings that concern the media properties, the scheduler 30 selects the holders 40 from which the sheets with the desired properties are to be taken and determines a sequence in which the sheets of the different media types are to be fed into the sheet transport path 18 such that the sequence of sheets matches the sequence of images to be printed.
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When the print process has been started, the feed control section 32 controls the feed mechanism 42 to supply the sheets in the sequence as scheduled into the sheet transport path 18, and the print control section 34 controls the print station 16 so as to print a corresponding image on the top side of each sheet.
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In the example shown, the output section 14 has a plurality of holders 44 on which the sheets may be deposited after they have left the print station 16. When a stack, which may for example comprise a set of sheets forming a complete copy of a multi-page document, has been completed, the holders 44 will forward the stack onto an associated output stacker 46. In an alternative embodiment the completed stacks may also be forwarded to a finisher (not shown) for performing finishing operation such as stapling, punching and the like.
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The output section 14 further includes a switch 48 which is controlled by the output control section 36 for directing each sheet to a designated one of the holders 44. The main body 12 of the printing section includes a duplex path 50 which branches off from the sheet transport path 18 downstream of the print station 16, reverses the orientation of the sheets in a sheet reversing mechanism 52 and then returns the sheets upside down to the entry side of the sheet transport path 18.
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It shall further be assumed in this example that the print station 16 includes as print engine an inkjet print head 54 that is disposed above the sheet transport path 18 and is adjustable in height by means of a height adjustment mechanism 56. Dependent upon the thickness and other properties of the sheets, the height of the print head 54 is adjusted such that a nozzle face 58 at the bottom side of the print head forms only a very narrow gap with a top surface of a sheet 60 that is being conveyed past the print head. In this way, it will be assured that, for each individual sheet, the inkjet print process will be performed with an optimal nozzle-to-sheet distance.
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As the gap between the nozzle face 58 and the sheet 60 may be very small, any wrinkles or a surface waviness or other surface irregularities of the sheet 60 may result in a poor image quality or even in a collision of the sheet with the print head. For this reason, a sentry 62 for monitoring the quality of the sheets is disposed at the sheet transport path 18 upstream of the print station 16. The sentry 62 may for example be a 3D laser scanner that scans the entire surface of the sheet in order to capture a surface relief. An example is described in
US 2016103634 A1 . The relief data are transmitted to the sheet manager 38 in the controller 20, where they are processed further to decide whether the quality of the sheet is acceptable or not. In this specification, a sheet will be designated as "damaged" if the quality detected by the sensor 62 is not acceptable. The sensor 62 may also detect other quality criteria relating to, for example, alignment errors or skew errors of the sheets.
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When a sheet is found to be damaged, the sheet manager 38 controls a switch 64 in the sheet transport path 18 in order to excise this sheet from the scheduled sequence and to divert it into a discharge path 66 via which the sheet is discharged into a discharge bin 68. In this way, the defective sheet will be skipped in the print process. However, the image that was designated for being printed onto the discarded sheet must nevertheless be printed. In duplex printing this may have the consequence that all the sheets that had been present already duplex path 50 have to be discarded as well, even if they are not damaged, because the wear the wrong image on their first side.
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It should be observed in this context that Fig. 1 is only a schematic sketch and that, in practice, the number of sheets that can be accommodated in the duplex path 50 can be considerably large. For example, the duplex path 50 may be arranged to accommodate as many as 40 sheets.
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Fig. 2 is a flow diagram 200 of an allocation method according to the prior art. On system level the print controller allocates an output stacker for depositing the printed sheets of the print job. The stacker allocation algorithm initially determines which output stacker is selected.
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In a first step S1 of the allocation method according to the prior art, a print job arrives at the printer to be printed on sheets.
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In a second step S2 it is checked if there is a system based stacker selection is in place like a stacker allocation algorithm. If not so, the method continues with a sixth step S6. Otherwise the method continues with a third step S3.
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In the third step S3 the stacker allocation algorithm is selected.
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In a fourth step S4 the stacker allocation algorithm indicates an output stacker A.
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In a fifth step S5 the printed sheets of the print job are deposited in the output stacker A.
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In the sixth step S6 it is checked if the print job has a specific value for the first print job property, for example stacker X (X is one of {1 ,2,....}). If not so, the method proceeds to an eighth step S8. Otherwise the method proceeds to a seventh step S7.
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In the seventh step S7 the printed sheets of the print job are deposited in stacker X.
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In the eighth step S8 the printed sheets of the print job are deposited in a default stacker. The default stacker is a stacker which has been preset by the printer at installation or re-installation.
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Fig. 3 is a flow diagram 300 of the method according to the present invention. A job level based allocation of the output stacker is implemented. A non-empty value of the first print job property of the print job indicates the stacker output location for depositing the printed sheets of the print job. When the first print job property has no value, i.e. is empty, not filled, the stacker allocation algorithm will be invoked. In that case the stack allocation algorithm indicates the output stacker in which the printed sheets of the print job will be deposited.
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In a first step T1 of the allocation method according to the present invention, a print job arrives at the printer to be printed on sheets.
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In the second step T2 it is checked if the print job has a specific value for the first print job property, for example stacker X (X is one of {1,2,....}). If so, the method proceeds to a sixth step T6. Otherwise the method proceeds to a third step T3. The specific value for the first print job property may also indicate a specific stacker allocation algorithm like "SA1". Then the allocation is determined by the first stacker allocation algorithm 1.
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In the sixth step T6 the printed sheets of the print job are deposited in stacker X.
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In the third step T3 the default stacker allocation algorithm is selected.
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In a fourth step T4 the default stacker allocation algorithm indicates an output stacker A. In a fifth step T5 the printed sheets of the print job are deposited in the output stacker A.
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Fig. 4 is an example of a representation of a print job queue 400 according to the present invention. A first print job 1 has a print job property "S" which does not indicate a specific output stacker, i.e. the print job property of the first print job 1 has no value. A second print job 2 has a print job property "S2" which indicates a second output stacker S2 of the printer for depositing the printed sheets of the second print job 2. A third print job 3 has a print job property "S1" which indicates a first output stacker S1 of the printer for depositing the printed sheets of the third print job 3. A fourth print job 4 has a print job property "S" which does not indicates a specific output stacker, i.e. the print job property of the fourth print job 4 has no value.
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Figs. 5 - 6 are outputs 500, 600 of deposition according to the prior art shown in Fig. 2 based on the example of the print job queue in Fig. 4. When the allocation method according to the prior art of Fig. 2 is implemented, the sheets will be output to the output stackers S1, S2 as shown in Figs. 5 or 6.
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Fig. 5 shows the output stackers S1, S2 when a stacker allocation algorithm is in place.
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The stacker allocation algorithm in this example in principle does not take into account the first print job properties of the print jobs in the print job queue in Fig. 4. The stacker allocation algorithm in this example is configured to select an output stacker with a lowest number that still has enough room to fit the printed sheets of the print job on.
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Therefore the print jobs 1, 2 and 3 are deposited into output stacker S1 and print job 4 is deposited into output stacker S2 since output stacker S1 is full after job 3 has been deposited in output stacker S1.
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Fig. 6 shows the output stackers S1, S2 when a stacker allocation algorithm is not in place. The first job property of the jobs 2 and 3 are taken into account. The printed sheets of print job 2 are directed to output stacker S2. The printed sheets of the print job 3 are directed to output stacker S1. The print jobs 1 and 4 do not have a specific value for the first print job property. Therefore the printed sheets of the print jobs 1 and 4 are directed to the default stacker which in this example is output stacker S2. In this example the default stacker is preset by the print controller to "S2" when the print controller is configured at installation or re-installation.
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Fig. 7 is output 700 of deposition according to the present invention based on the example of the print job queue in Fig. 4. The allocation method according to the present invention leads to a deposited output in the output stackers S1 and S2 as shown in Fig. 7. The outcome will be further explained hereinafter.
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In the example according to Fig. 4, the output stacker for the printed sheets of the first job 1 is determined by the stacker allocation algorithm because the first print job property of the first print job 1 indicates "S" as output stacker which means that the first print job property has no value. In the example of Fig. 4 and Fig. 7 the multiple output stackers S1 and S2 are subsequently numbered 1 and 2 respectively. The default stacker allocation algorithm is configured to select the output stacker with a lowest number that still has enough room to fit the printed sheets of the first print job 1 on. Since both output stackers S1 and S2 are empty at the arrival of the print job in the printer, the sheets of the first job 1 are directed to output stacker S1 when printed as shown in Fig. 7, since output stacker S1 has number 1.
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In the example according to Fig. 4, the output stacker for the printed sheets of the second job 2 is determined by the first print property of the second print job 2 which indicates "S2" as output stacker. As shown in Fig. 7 the sheets of the second job 2 are directed to output stacker S2 when printed.
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In the example according to Fig. 4, the output stacker for the printed sheets of the third job 3 is determined by the first print property of the third print job 3 which indicates "S1" as output stacker. As shown in Fig. 7 the sheets of the third job 3 are directed to output stacker S1 when printed.
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In the example according to Fig. 4, the output stacker for the printed sheets of the fourth job 4 is determined by the stacker allocation algorithm because the first print job property of the fourth print job 4 indicates "S" as output stacker which means that the first print job property has no value. In the example of Fig. 4 and Fig. 7 the multiple output stackers S1 and S2 are subsequently numbered 1 and 2 respectively. The default stacker allocation algorithm is configured to select the output stacker with a lowest number that still has enough room to fit the printed sheets of the fourth print job 4 on. The output stacker S1 now contains the sheets of the first print job 1 an the third print job 3, but still has enough room to fit the sheets of the fourth print job 4. Therefore, as shown in Fig. 7, the sheets of the fourth print job 4 are directed to output stacker S1 when printed.
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In case that the output stacker S1 is full after the printed sheets of the fourth print job 4 are deposited in the output stacker S1, the output stacker S1 has to be emptied before any next sheet can be deposited in output stacker S1.
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So, if a next print job 5 (not shown) arrives at the printer, there are three possible cases which might occur.
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In a first case the first print job property of the fifth print job 5 indicates an output stacker "S1". Then the output stacker S1 will be emptied before the sheets of the fifth print job 5 are deposited in the output stacker S1.
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In a second case the first print job property of the fifth print job 5 indicates an output stacker "S", i.e. there is no value for the first print job property. Then the default stacker allocation algorithm takes over and the sheets of the fifth print job 5 are deposited in the output stacker S2 having the next lowest number than 1, namely 2.
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In a third case the first print job property of the fifth print job 5 indicates an output stacker "S2". Then the sheets of the fifth print job 5 are deposited in the output stacker S2, unless the second print job 2 has completely filled the output stacker S2. In the latter case the output stacker S2 will be emptied firstly.
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It is concluded from the Figs. 4 - 7 that the allocation of the printed sheets of the print jobs to the multiple output stackers according to the prior art method shown in Fig. 2 differs from the allocation of the printed sheets of the print jobs to the multiple output stackers according to the method of the present invention as shown in Fig. 3. According to the present invention the print controller is able to control deposition of the sheets of print jobs on different stacks in a multi-output location stacker system purely based on the print job itself and without the need to explicitly indicate an exact location for all print jobs.
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According to an embodiment the print controller comprises a collection of stacker allocation algorithms and the non-empty value of the first print job property indicates a stacker allocation algorithm out of the collection. For example, the first print job property may be "SA1" indicating a first stacker allocation algorithm in the collection or a stacker allocation algorithm numbered as 1.
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A stacker allocation algorithm in the collection may be according to any of the following examples. The multiple output stackers are sequenced in a sequence and a stacker allocation algorithm out of the collection is for example configured to select an output stacker which is first in the sequence and meets a certain condition. More examples of stacker allocation algorithms with other conditions than mentioned in the examples hereinbelow may be envisioned.
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In a first example the output stacker must still have enough room to fit the printed sheets of the print job.
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In a second example the content of the output stacker plus the printed sheets of the print job must not exceed a predetermined height or weight. The predetermined height or weight may be determined by the volume of the output stacker or by a requirement of a post-processing device.
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In a third example the output stacker is first in the sequence that is empty.
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In a fourth example the output stacker is closest to the print engine.
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In a fifth example the output stacker is farthest from the print engine.
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The stacker allocation algorithms may be combined by means of a Boolean AND/OR construction. For example the third and fifth example may be combined so that an empty output stacker is selected which is farthest away from the print engine. In the latter case the first print job property may be "SA3&5" indicating an AND combination of the stacker allocation algorithms in the third and fifth example hereinabove.
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Fig. 8 schematically shows a non-transitory software medium 110 according to the invention. The software medium 110 comprises executable code 102 configured to, when executed, perform the method according to the invention, e.g. as described with respect to either the printer shown in Fig. 1 or the method shown in Fig. 3 and/or according to any of the variants and modifications of the printer and/or of the method described hereinbefore.
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The non-transitory software medium 110 may, specifically, be formed as a CD or a CD-ROM, a DVD or a DVD-ROM, a Blu Ray disc or a Blu Ray-ROM disc, a magnetic hard drive, a solid state disk (SSD) hard drive, a USB memory device and so on.
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Although specific embodiments of the invention are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are examples only and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.
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It will also be appreciated that in this document the terms "comprise", "comprising", "include", "including", "contain", "containing", "have", "having", and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms "a" and "an" used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms "first", "second", "third", etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.
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The present invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.