Patent Application
20230017413
The present invention relates to an image forming apparatus and a control method thereof.
In image forming apparatuses in which an image is printed by discharging and fixing ink onto a sheet-like print medium, image forming apparatuses in which ink is discharged by a print head onto a print medium fed from a roll into which the print medium has been wound and then the printed portion is wound into a rolled shape are known. When a printed print medium is wound into a rolled shape, if ink discharged onto the print medium has not sufficiently dried, the undried ink is retransferred to the print medium after being wound, and so the ink discharged onto the print medium is dried by a drying apparatus.
Incidentally, there are cases where a printing operation is stopped for some reason and a conveyance apparatus is also stopped accordingly. When a conveyance apparatus is stopped, a print medium stopped in the drying apparatus will be excessively heated, and therefore, a printing apparatus described in Japanese Patent Laid-Open No. 2015-182245 provides a function of moving out a printed region from the drying apparatus for when the operation of a conveyance unit is stopped for a predetermined time or more.
However, in the printing apparatus described in Japanese Patent Laid-Open No. 2015-182245, since a printed portion is stopped and remains inside the drying apparatus for a predetermined time, it is impossible to prevent the occurrence of a difference from a portion on which a normal drying operation has been performed. If a printed region is excessively heated, there occurs partial unevenness or deformation or change in a print substrate due to an increase in temperature, and therefore, there is a problem that the quality of printed matter deteriorates.
The present invention has been made in view of the above problem and provides an image forming apparatus capable of suppressing deterioration in the quality of printed matter caused by excessive drying of a print medium.
According to a first aspect of the present invention, there is provided an image forming apparatus comprising: a conveyance unit configured to convey a long-shaped print medium in a longitudinal direction; an image forming unit configured to form an image on the print medium; a drying unit configured to dry the print medium on which an image has been formed in the image forming unit; and a control unit configured to, after interrupting image formation on the print medium by the image forming unit, control the image forming unit and the conveyance unit so as to convey a portion of the print medium on which image formation has been performed up to an ejection position at which the portion is ejected from inside of the drying unit and then stop the conveyance.
According to a second aspect of the present invention, there is provided a method of controlling an image forming apparatus having a conveyance unit configured to convey a long-shaped print medium in a longitudinal direction, an image forming unit configured to form an image on the print medium, and a drying unit configured to dry the print medium on which an image has been formed in the image forming unit, the method comprising: after interruption of image formation on the print medium by the image forming unit, controlling the image forming unit and the conveyance unit so as to convey a portion of the print medium on which image formation has been performed up to an ejection position at which the portion is ejected from inside of the drying unit and then stop the conveyance.
According to a third aspect of the present invention, there is provided a non-transitory computer readable storage medium storing a program for causing a computer to execute a method of controlling an image forming apparatus having a conveyance unit configured to convey a long-shaped print medium in a longitudinal direction, an image forming unit configured to form an image on the print medium, and a drying unit configured to dry the print medium on which an image has been formed in the image forming unit, the method comprising: after interruption of image formation on the print medium by the image forming unit, controlling the image forming unit and the conveyance unit so as to convey and then stop at an ejection position at which the portion has been ejected from inside of the drying unit a portion of the print medium on which image formation has been performed.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note, the following embodiments are not intended to limit the scope of the claimed invention. Multiple features are described in the embodiments, but limitation is not made to an invention that requires all such features, and multiple such features may be combined as appropriate. Furthermore, in the attached drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.
Hereinafter, a configuration of an image forming apparatus according to a first embodiment of the present invention will be described.
In
In the roll feeding apparatus 102, a roll 106 into which an unprinted print substrate 110 has been wound is disposed, and the print substrate 110 is pulled out from the roll 106 and is printed. In the printing apparatus 103, a print head 107 is disposed, and printing is performed by discharging ink onto the print substrate 110. Printed matter 111 on which printing has been performed (the print substrate 110 on which printing has been performed) is dried by a dryer 108 in the drying apparatus 104. The dried printed matter 111 is wound by the roll winding apparatus 105 to form a roll 109 of printed matter.
In
The substrate conveyance unit 202 is a conveyance mechanism that conveys the long-shaped print substrate 110 wound into a rolled shape and mounted on the image forming apparatus 100 in a longitudinal direction. It is a mechanism for conveying the print substrate 110 fed from the roll feeding apparatus 102 by a plurality of conveyance rollers to the printing apparatus 103 and conveying the printed matter 111 printed by the printing apparatus 103 to the roll winding apparatus 105 via the drying apparatus 104.
The printing apparatus 103 forms an image on the print substrate 110 fed from the roll feeding apparatus 102 based on print data for which a print instruction has been received.
The communication unit 204 is configured by a communication control card such as a LAN (Local Area Network) card. It transmits and receives various kinds of data to and from an external apparatus (e.g., a personal computer) connected to a communication network such as a LAN and a WAN (Wide Area Network).
The control panel 101 is provided with, for example, the display unit 206 and the operation unit 207 configured by a liquid crystal display (LCD) with a touch panel. The display unit 206 displays various kinds of information on a display screen in accordance with a display control signal inputted from the control unit 201. In addition to the above-described touch panel, the operation unit 207 is provided with various input devices such as a keyboard and a mouse and receives various input operations by a user and outputs operation signals to the control unit 201.
The storage unit 208 is configured by a volatile semiconductor memory (so-called flash memory), an HDD (Hard Disk Drive), and the like. The storage unit 208 stores various programs including a system program and a processing program to be executed by the control unit 201 and various kinds of data necessary for execution of these programs.
The roll feeding apparatus 102 supplies the print substrate 110 wound into a rolled shape for printing in the printing apparatus 103. The roll winding apparatus 105 winds the printed matter 111 printed by the printing apparatus 103 and dried by the drying apparatus 104 into a rolled shape. Winding into a rolled shape makes it easier to execute management and delivery. The roll feeding apparatus 102 is disposed upstream in a conveyance direction of the substrate conveyance unit 202 with respect to the printing apparatus 103, and the roll winding apparatus 105 is disposed downstream in the conveyance direction of the substrate conveyance unit 202 with respect to the drying apparatus 104.
The drying apparatus 104 is provided with a dryer that has a heating element, which becomes hot, and blows hot air. When the ink in a portion printed by the printing apparatus 103 is not sufficiently dry and is directly wound by the roll winding apparatus 105, the undried ink is retransferred to the print substrate 110. Therefore, it is necessary to perform sufficient drying. Drying is performed by controlling temperature and air volume in accordance with the characteristics of the print substrate 110. If a set temperature is too high, the print substrate 110 may become deformed, and if it is too low, the printing surface will not be sufficiently dry.
Next, the operation for when printing is performed on the print substrate 110 in the image forming apparatus 100 according to the present embodiment will be described.
As illustrated in
As illustrated in
When executing a plurality of print jobs in a roll-to-roll image forming apparatus in which the print substrate 110 is pulled out from the roll 106 into which the unprinted print substrate 110 has been wound and the printed matter 111 is wound into a rolled shape after printing and drying, it is desirable that generation and printing of all the print jobs are executed continuously without delay. If generation of a print job is delayed, there is no data to be printed and printing cannot be performed, and so either of the following two situations will occur. One is a situation in which the conveyance of a print substrate is continued while leaving it blank and printing is resumed when print job generation is completed, and the other is a situation in which the conveyance of a print substrate is temporarily stopped and the completion of print job generation is awaited.
First, in step S501, the control unit 201 starts printing an N-th print job. Here, N is an integer.
In step S502, the control unit 201 determines whether or not printing of the N-th print job (a print job for which image formation is currently being performed) will be completed. If the printing of the N-th print job will be completed, the processing proceeds to step S503, and if the printing will not be completed, the printing is continued.
In step S503, the control unit 201 determines whether or not an N+1-th print job is ready. If the print job is ready, the processing proceeds to step S504, and if it is not ready, the processing proceeds to step S505.
In step S504, 1 is added to N, and printing is continued.
Meanwhile, if the print job is not ready in step S503, the next printing cannot be performed until the print job is ready. The following reasons are conceivable as causes of the N+1-th print job not being ready during printing of the N-th print job: the input timing of the N+1-th print job is late, the processing time of the N+1-th print job by a RIP is longer than the printing time of the N-th print job, and the like. However, in the present embodiment, causes thereof are irrelevant.
In step S505, the control unit 201 determines whether or not to stop the conveyance of the print substrate 110 in a state in which printing cannot be performed. When stopping, the processing proceeds to step S506, and when not stopping, the processing proceeds to step S509.
In step S506, the control unit 201 stops the conveyance of the print substrate 110. In step S507, the control unit 201 determines whether or not the N+1-th print job, that is, the next print job, is ready. If the print job is ready, the processing proceeds to step S508; otherwise, it is waited until it is ready.
In step S508, the control unit 201 resumes printing from a position at which the print substrate 110 has been stopped.
If the conveyance of the print substrate 110 is not stopped in step S505, in step S509, the control unit 201 does not perform printing and only conveys the print substrate 110. Printing is made to wait until the N+1-th print job, that is, the next print job, is ready, and only the conveyance of the print substrate 110 is performed.
When the next print job is ready in step S509, in step S510, the control unit 201 resumes printing. Such a method of stopping only printing and continuing the conveyance of the print substrate 110 is effective when it is expected that the printing speed will be slow and the next print job will be immediately ready.
If the conveyance of the substrate 110 is stopped when printing cannot be continued and it is waited until the next print job is ready as in steps S506 to S508, a printed portion of the N-th print job is being dried in the drying apparatus 104. When the conveyance of the print substrate 110 is stopped in this state, since the printed portion is exposed to excessively high temperature, unevenness and change or deformation of the print substrate may occur due to excessive drying. In order to prevent this, as will be described below, the conveyance operation is performed without stopping until a printed portion (a portion on which an image has been formed) of the N-th print job passes through and exits outside the drying apparatus 104 and the conveyance operation is stopped when the printed portion exits outside in the present embodiment.
In step S503, if the N+1-th print job is not ready, the next print cannot be performed until the print job is ready, but the N-th print job is in a drying process in the drying apparatus 104. When printing of the N-th print job is completed, if the conveyance processing is stopped in order to wait for the N+1-th print job to be ready, an N-th print result stops inside the drying apparatus 104 and may be dried more than necessary, thereby becoming overdried. Therefore, in step S601, after a normal drying process of a printed portion has been completed, the control unit 201 calculates the conveyance amount necessary for stopping the printed portion outside the drying apparatus 104 (an ejection position) and conveys the printed matter 111 by the calculated conveyance amount after the printing has been stopped.
In step S602, the control unit 201 stops the conveyance of the printed matter 111 when the print region exits outside the drying apparatus.
In step S507, the control unit 201 determines whether or not the N+1-th print job, that is, the next print job, is ready. If the print job is ready, the processing proceeds to step S508; otherwise, it is waited until it is ready.
In step S508, the control unit 201 resumes printing from a position at which the print substrate 110 has been stopped.
As described above, in the above-described first embodiment, when the next print job is not ready after printing has been completed, after the normal drying of the printed portion has been performed, conveyance is continuously performed until the portion exits the drying apparatus and is stopped. In that state, the next print job becoming ready is awaited. This makes it possible to prevent overdrying of the printed portion.
Hereinafter, a second embodiment of the present invention will be described. In the second embodiment, a mark is printed at an interruption start position and an interruption end position at the time of print interruption. By printing marks that indicate the interruption positions, it is possible to clearly distinguish the portion in which print interruption has been performed in the processing performed after printing.
In step S503, if the N+1-th print job is not ready, the next print cannot be performed until the print job is ready, but the N-th print job is in a drying process in the drying apparatus 104. When printing of the N-th print job is completed, if the conveyance processing is stopped in order to wait for the N+1-th print job to be ready, an N-th print result stops inside the drying apparatus 104 and may be dried more than necessary, thereby becoming overdried. In order to prevent overdrying, processing is performed in which a printed portion is stopped outside the drying apparatus 104 after completion of a normal drying process. In such a case, since the N+1-th print job is not printed and only the conveyance processing is performed, a blank region in which nothing is printed is created. The blank region is originally a position where the N+1-th print job is to be printed, and depending on later processing, it is necessary to indicate that it is a blank region or make the print regions continuous by connecting them after cutting out the blank region. Therefore, in step S801, the control unit 201 prints a print interruption start mark after printing the N-th print job.
In step S601, after the normal drying process of a printed portion has been completed, the control unit 201 calculates the conveyance amount necessary for stopping outside the drying apparatus 104 and conveys the printed matter 111 by the calculated conveyance amount after printing is stopped.
In step S602, the control unit 201 stops the conveyance of the printed matter 111 when the print region exits outside the drying apparatus.
In step S507, the control unit 201 determines whether or not the N+1-th print job, that is, the next print job, is ready. If the next print job is ready, the processing proceeds to step S508; otherwise, it is waited until it is ready.
In step S802, the control unit 201 prints an interruption end mark.
In step S803, the control unit 201 resumes printing of the N+1-th print job after printing the interruption mark.
In the second embodiment, the print data of the N-th print job and the print data of the N+1-th print job are illustrated to be different, but they may be the same. Although the interruption start mark and the interruption end mark has been represented by dotted lines, they are not limited to these and may be of other forms. For example, they may be symbols such as circles, triangles, and squares as long as their position can be identified. Furthermore, the interruption start mark and the interruption end mark may be of other shapes. It is also possible to give meaning by the colors of the marks or print with special ink so that it is invisible to the human eye but can be sensed by sensors.
As described above, according to the second embodiment, it is possible to prevent overdrying of the printed portion as in the first embodiment as well as clearly distinguish the portion where print interruption has been performed in processing performed after printing.
Hereinafter, a third embodiment of the present invention will be described. In the third embodiment, a case where a plurality of drying apparatuses 104 of
When printed matter is wound into a rolled shape in a state in which the ink at a printed portion is not sufficiently dry, the undried ink is retransferred to the print substrate 110, and so it is necessary to sufficiently dry the ink. The drying apparatus 104 performs control of the temperature and an air volume applied to printed matter in accordance with the characteristics of the print substrate. In such cases, there may be cases where the drying temperature cannot be increased due to the characteristics of the print substrate 110 or cases where the material of the print substrate 110 is a material that is difficult to dry. For such cases, a method in which a plurality of drying apparatuses are connected to improve drying ability is known. Since the amount of heat and time necessary for drying vary depending on the substrate to be printed, it is not necessary to always use a plurality of drying apparatuses for all the print substrates even if an image forming apparatus is that in which a plurality of drying apparatuses are connected. It need only be that a drying apparatus to be used is selected in accordance with the characteristics of the print substrate.
Furthermore, since it is cumbersome to attach or remove the drying apparatuses, it is sufficient not to perform the drying operation in some drying apparatuses while the plurality of drying apparatuses remain connected. Therefore, even when interrupting printing and making it so that a printed portion does not stop in a drying apparatus, it is not necessary to convey the printed portion outside all the drying apparatuses, and it is sufficient that the printed portion is conveyed outside the drying apparatuses being used.
In step S1101, the control unit 201 acquires information for determining whether or not the respective drying apparatuses are being used.
In step S1102, the control unit 201 determines whether or not usage information has been acquired from all the drying apparatuses that are connected and repeats step S1101 until acquisition is made from all the drying apparatuses.
In step S1103, the control unit 201 identifies the drying apparatuses being used among all the drying apparatuses.
In step S1104, the control unit 201 acquires information on an inner conveyance length of the drying apparatuses being used.
In step S1105, the control unit 201 calculates an conveyance amount by which a print substrate is to be conveyed at the time of a temporary stop based on the sum of the length of conveyance inside all the drying apparatuses being used.
As described above, according to the present embodiment, performing the conveyance operation by only a necessary amount at the time of print interruption makes it possible to reduce wasteful print substrate on which printing is not performed.
Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as anon-transitory computer-readable storage medium') to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2021-115830, filed Jul. 13, 2021, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-115830 | Jul 2021 | JP | national |
