JP2006084632A - Printer, printing jam removing method and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily remove a jammed recording medium. <P>SOLUTION: In the color laser printer 20, recording paper sensors 34a, 34b, and 34c for detecting recording paper S are disposed. Using the output values of the sensors, a jamming occurring in a distance (a prescribed range) between a pair of transfer rollers 30 and a pair of fixing rollers 40 is detected. When there is an occurrence of jamming in the prescribed range, a CPU rotates a transfer roller 31 so that the recording paper S is conveyed downstream, and makes a fixing roller 41 rotate in reverse so that the recording paper S is conveyed upstream. Based on the output values of the recording paper sensors 34a and 34c, the recording paper S is brought to a state, in which it is almost sandwiched neither between the pair of rollers 30 nor the pair of rollers 40 in the prescribed range. Then, the transfer roller 31 and the fixing roller 41 are stopped at a position, where the recording paper S is held by at least either the pair of rollers 30 or the pair of rollers 40. If the recording paper S, being subjected to printing has a large load, as in cardboard, the removal of jamming is inhibited. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printer, a print jam processing method, and a program therefor.

2. Description of the Related Art Conventionally, printers that transfer a toner image onto a recording sheet with a transfer roller and then fix the toner image with a fixing roller have been proposed that process the jammed recording sheet with a fixing roller (see FIG. For example, see Patent Document 1). In the printer described in Patent Document 1, when a jam occurs in the recording paper on the fixing roller, the fixing roller is stopped and then the transfer roller is stopped after a predetermined time has elapsed, or the fixing roller and the transfer roller are stopped. Depending on whether the fixing roller is rotated in the reverse direction, the recording paper is bent between the transfer roller and the fixing roller. Since the user can insert a finger into the bent portion, it is easier to remove the jammed recording paper as compared with the case where there is no gap between the recording paper conveyance surface and the recording paper.
JP-A-7-157141 (FIG. 2)

  However, in the printer described in Patent Document 1, since the jammed recording paper is strongly held between the fixing roller and the transfer roller, the user has to pull out and still jams. It was difficult to remove the recording paper.

  SUMMARY An advantage of some aspects of the invention is that it provides a printer, a print jam processing method, and a program for easily removing a jammed recording medium.

  The present invention adopts the following means in order to achieve the above-mentioned object.

The printer of the present invention
A printer that conveys a recording medium and prints an image on the recording medium,
Upstream transport means for sandwiching the recording medium and transporting the recording medium downstream;
A downstream transport unit disposed downstream of the upstream transport unit and sandwiching the recording medium transported by the upstream transport unit to transport the recording medium downstream;
A jam detecting means for detecting occurrence of a jam of the recording medium between the upstream side conveying means and the downstream side conveying means;
When the jam is detected by the jam detecting means, the recording medium is not substantially held between the upstream conveying means and the downstream conveying means between the upstream conveying means and the downstream conveying means. A transport control means for controlling the upstream transport means and the downstream transport means until
It is equipped with.

  In this printer, when a jam is detected between the upstream side conveying unit and the downstream side conveying unit, the recording medium moves between the upstream side conveying unit and the downstream side conveying unit between the upstream side conveying unit and the downstream side conveying unit. The upstream-side transport unit and the downstream-side transport unit are controlled until they are almost not sandwiched between them. Therefore, the jammed recording medium can be easily removed as compared with the case where the recording medium is strongly held by the conveying means. The “substantially not pinched state” includes a state in which the recording medium is not pinched at all and a state in which the end of the recording medium is pinched to the extent that there is no problem in pulling out the recording medium.

  At this time, when the jam is detected by the jam detection unit, the conveyance control unit is configured to move the recording medium between the upstream conveyance unit and the downstream conveyance unit between the upstream conveyance unit and the downstream conveyance unit. And the downstream conveying means so that the recording medium is conveyed to the upstream side and the upstream conveying means is controlled so that the recording medium is conveyed to the downstream side until the recording medium is not sandwiched between the two. May be controlled.

  In the printer according to the aspect of the invention, the jam detection unit may detect the occurrence of a jam when the recording medium is sandwiched between the upstream conveyance unit and the downstream conveyance unit, and perform the conveyance control. When the jam is detected by the jam detecting means, the recording medium is placed between the upstream conveying means and the downstream conveying means between the upstream conveying means and the downstream conveying means. You may control this upstream conveyance means and this downstream conveyance means until it will be in the state which is not clamped substantially.

  The printer of the present invention includes an instruction acquisition unit that acquires a jam processing instruction from a user, and the transport control unit detects a jam by the jam detection unit and acquires an instruction of the jam processing by the instruction acquisition unit. The upstream conveying means until the recording medium is substantially not sandwiched between the upstream conveying means and the downstream conveying means between the upstream conveying means and the downstream conveying means. And the downstream conveying means may be controlled. In this way, it is possible to perform jam processing in which the recording medium is not sandwiched between the upstream transport unit and the downstream transport unit between the upstream transport unit and the downstream transport unit in accordance with a user instruction.

  In the printer of the present invention, the downstream conveying unit may be a heat roller type fixing unit that fixes the toner image to the recording medium by heating the recording medium on which the toner image is transferred. . In the heat roller type fixing means, since the toner image is fixed, the pressure for pinching the recording medium is high. Therefore, the recording medium is easily jammed, and it is difficult for the user to pull out the jammed recording medium. Therefore, it is highly significant to employ a heat roller type fixing unit as the downstream conveying unit of the present invention. At this time, the upstream side conveying means is a conveying roller for nipping and conveying the recording medium by a roller, and the conveying control means is configured such that when the jam is detected by the jam detecting means, the recording medium is moved to the conveying roller. The recording roller is rotated so that the recording medium is conveyed downstream until the recording medium is not sandwiched between the conveying roller and the fixing unit. The fixing unit may be rotated so as to be conveyed upstream. In this way, it is possible to perform jam processing relatively easily.

  The printer of the present invention comprises storage means for storing the type of the recording medium currently printed, and the transport control means is a predetermined prohibition in which the type of the recording medium stored in the storage means is predetermined. When the recording medium is a recording medium, the recording medium is not sandwiched between the upstream conveying means and the downstream conveying means between the upstream conveying means and the downstream conveying means. Control may be prohibited. By so doing, jam processing is prohibited when a predetermined prohibited recording medium becomes jammed, so the load of jam processing can be reduced. Here, “type of recording medium” includes, for example, paper size, paper quality, and the like. In addition, the “predetermined prohibited recording medium” is a recording medium (thick paper or OHP) that may cause a load on the upstream conveying unit and the downstream conveying unit due to, for example, jam processing, and cause a printer failure. Film etc.).

  The printer of the present invention includes a load detection unit that detects a load of the upstream side conveyance unit and the downstream side conveyance unit that conveys the recording medium, and the conveyance control unit detects the load detected by the load detection unit. When a predetermined load value is exceeded, the recording medium is not substantially sandwiched between the upstream transport unit and the downstream transport unit between the upstream transport unit and the downstream transport unit. Control to do so may be prohibited. By doing so, it is possible to prevent the upstream conveying unit and the downstream conveying unit from being loaded with a load exceeding a predetermined load value, and therefore it is possible to prevent a printer failure due to excessive loading. Here, the “predetermined load value” may be determined as a load value that may cause the printer to malfunction due to, for example, jam processing.

  The printer of the present invention further comprises position detection means for detecting the position of the recording medium, and the transport control means is configured such that the recording medium is on the upstream side based on the position of the recording medium detected by the position detection means. It is held between at least one of the upstream side transport unit and the downstream side transport unit in a state where it is not substantially sandwiched between the upstream side transport unit and the downstream side transport unit between the transport unit and the downstream side transport unit. In this manner, the upstream side conveyance unit and the downstream side conveyance unit may be controlled. In this way, the jammed recording medium can be held between the upstream transport unit and the downstream transport unit.

The printing jam processing method of the present invention includes:
A printing jam processing method by computer software for processing a jam of a recording medium generated when the recording medium is sandwiched and conveyed by an upstream conveying unit and a downstream conveying unit,
(A) detecting the occurrence of jam of the recording medium between the upstream side conveying unit and the downstream side conveying unit;
(B) When the jam is detected in the step (a), the recording medium is positioned between the upstream side transport unit and the downstream side transport unit between the upstream side transport unit and the downstream side transport unit. Also controlling the upstream transport means and the downstream transport means until the state is not substantially pinched,
Is included.

  In this printing jam handling method, when a jam is detected between the upstream transport unit and the downstream transport unit, the recording medium is transferred between the upstream transport unit and the downstream transport unit. The upstream-side conveyance unit and the downstream-side conveyance unit are controlled until they are not substantially held by any of the conveyance units. Therefore, the jammed recording medium can be easily removed as compared with the case where the recording medium is strongly held between at least one of the upstream side conveying unit and the downstream side conveying unit. Here, the “substantially not pinched state” includes a state in which the recording medium is not pinched at all, and a state in which only the end of the recording medium is pinched to the extent that there is no problem in pulling out the recording medium. In this print jam processing method, various aspects of the printer described above may be adopted, and steps for realizing the functions of the printer described above may be added.

  The program of the present invention is for causing one or more computers to execute each step of the above-described reuse price determination method. This program may be recorded on a computer-readable recording medium (for example, hard disk, ROM, FD, CD, DVD, etc.), or from a computer via a transmission medium (communication network such as the Internet or LAN). It may be distributed to another computer, or may be exchanged in any other form. If this program is executed on one computer or distributed to a plurality of computers, each step of the above-described print jam processing method is executed, so that the same effects as the above-described print jam processing method can be obtained. It is done.

  Next, the best mode for carrying out the present invention will be described using examples.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an outline of the configuration of a color laser printer 20 according to an embodiment of the present invention. FIG. 2 shows the configuration of a secondary transfer unit 28 and a fixing unit 29 (dotted line portion in FIG. 1). It is a block diagram which shows the outline of this. First, the configuration of the color laser printer 20 used by the user will be described with reference to FIG.

  The color laser printer 20 is configured as a full-color electrophotographic printing apparatus that employs a single photoreceptor system and an intermediate transfer system, and includes a charger 21 that charges the surface of the photoreceptor 22, cyan (C), and magenta. (M), yellow (Y), black (K), an exposure unit 23 for forming an electrostatic latent image of each color separated into four colors on the charged photoconductor 22, and each mounted color The developer 24 that develops the electrostatic latent image formed on the photosensitive member 22 as a toner image using the toner of each color supplied from the toner cartridges 24C, 24M, 24Y, and 24K of the toner cartridge is superimposed on the developed toner image. The four-color toner formed on the transfer belt 25 on the transfer belt 25 as an intermediate transfer member for primary transfer and on the recording paper S conveyed by the conveyance unit 27 from the recording paper tray 26. The secondary transfer to the secondary transfer unit 28, a fixing unit 29 for melting the four color toner images transferred onto the recording sheet S to the recording sheet S fixing, those having a. The developing device 24 is configured to be rotatable such that the mounted toner cartridges 24K, 24C, 24M, and 24Y face the photosensitive member 22, respectively. The charging member 21 applies a high voltage to the wire and charges the photosensitive member 22 using ions generated by corona discharge. The exposure unit 23 is scanned by a polygon mirror that is driven to rotate by a motor. The photosensitive member 22 is exposed by a laser beam.

  Next, the secondary transfer unit 28 and the fixing unit 29 will be described with reference to FIG. The transfer roller pair 30 includes a transfer roller 31 and a belt roller 32. The secondary transfer unit 28 sandwiches and conveys the recording paper S by the transfer roller pair 30 and applies a voltage directly to the conductive transfer roller 31 to transfer the toner image formed on the transfer belt 25 to the recording paper S. This is a roller transfer unit. The transfer roller 31 is rotationally driven via a gear mechanism 38 by a main motor 37 controlled by a drive circuit 36. The gear mechanism 38 includes an electromagnetic clutch (not shown) that can turn on and off the connection between the main motor 37 and a transfer roller 31 and a fixing roller 41 (described later). A recording paper sensor 34 a that detects the presence or absence of the recording paper S is disposed near the upstream of the transfer roller 31. The recording paper sensor 34a is a contact type micro switch sensor, and outputs an ON signal when the recording paper S is conveyed and the leading end portion of the recording paper S passes the sensor position, and the trailing end portion of the recording paper S is the sensor. When the position is passed, an off signal is output.

  The fixing roller pair 40 includes a fixing roller 41 and a pressure roller 45. The fixing unit 29 sandwiches and conveys the recording paper S on which the toner image has been transferred by the fixing roller pair 40 and heats the recording paper S by the heater 43 of the fixing roller 41 to form a toner image formed on the recording paper S. Is a heat roller unit for fixing the toner image on the recording paper S. The fixing roller 41 is provided with a rubber layer 41b on the outer periphery of a cylindrical metal core 41a having a heater 43 therein, and is rotationally driven via a gear mechanism 38 by a main motor 37 controlled by a drive circuit 36. It is like that. The pressure roller 45 is formed with an elastic layer 45b such as rubber around a metal shaft 45a. The pressure roller 45 is urged by a spring (not shown) so as to be in contact with the fixing roller 41 and is rotatably supported. In the fixing unit 29 configured in this manner, the recording paper S on which the color toner image is transferred is supplied from the B direction between the fixing roller 41 rotating in the A direction in FIG. 2 and the pressure roller 45 driven by friction. Then, the toner image heated and pressed by the fixing roller 41 and the pressure roller 45 heated by the heater 43, and the toner image transferred on the surface thereof is melted and fixed on the recording paper S. The fixing roller 41 is rotationally driven by a main motor 37 controlled by a driving circuit 36 via a gear mechanism 38 and a rotation switching device 39.

  The rotation switching device 39 includes a reverse rotation gear (not shown), and includes a rotation direction (A direction) in which the fixing roller 41 conveys the recording paper S downstream, and a rotation direction (A) in which the recording paper S is conveyed upstream. To the opposite direction). The rotation direction is switched by electromagnetically connecting a reverse gear. A recording paper sensor 34b, which is the same sensor as the recording paper sensor 34a, is disposed in the vicinity of the upstream of the fixing roller 41, and a recording paper, which is the same sensor as the recording paper sensor 34a, in the vicinity of the downstream of the fixing roller 41. A sensor 34c is arranged. Here, it is assumed that the rotation direction of the fixing roller 41 is switched by the rotation switching device 39 having a reverse gear, but a sub motor is provided in addition to the main motor 37, and the rotation direction of the fixing roller 41 is switched by this sub motor. It may be done.

  The color laser printer 20 includes a controller 11 and an operation panel 15. The controller 11 is configured as a microprocessor centered on a well-known CPU 12, and includes a ROM 13 that stores a processing program and a RAM 14 that temporarily stores data. The operation panel 15 is a panel that includes a display unit 16 that displays various types of information on a display, and an operation unit 17 that can input various types of information to the controller 11 by button operation or panel touch. Further, the controller 11 includes an input / output port (not shown), and a signal from the operation unit 17 and signals from the recording paper sensors 34a, 34b, and 34c are input via the input port to the display unit 16. A signal, a drive signal to the drive circuit 36, a signal to the gear mechanism 38, a signal to the rotation switching device 39, and the like are output via the output port.

  Next, regarding the operation of the color laser printer 20 of the present embodiment configured as described above, the printing operation will be described first. When printing is instructed, the CPU 12 of the color laser printer 20 reads out the type of the recording paper S to be printed from the print data and stores it in the RAM 14, and an image of one of the four colors C, M, Y, K. Read data from print data. This type of recording paper includes paper size and quality. Next, the CPU 12 charges the photosensitive member 22 with the charging member 21, applies a laser beam to the surface of the photosensitive member 22 with the exposure device 23 based on the read image data, weakens the charge only for the portion of the image data, and electrostatic latent image. An image is formed (exposure), a voltage is applied to the toner, and the charged toner is attached to the electrostatic latent image on the photoreceptor 22 to form a toner image on the photoreceptor 22 (development). Subsequently, the CPU 12 transfers the toner image formed on the photoconductor 22 onto the transfer belt 25 (primary transfer). If there are any of the four colors C, M, Y, and K that have not been subjected to the above processing, the above processing is performed for that color. At this time, the developing device 24 is switched by 90 degrees to sequentially develop the toner images of the respective colors and superimpose them on the transfer belt 25. On the other hand, when the four color toner images are overlaid on the transfer belt 25, the CPU 12 causes the secondary transfer unit 28 to transfer the four color toner images on the transfer belt 25 onto the recording paper S. Secondary transfer. Finally, the CPU 12 conveys the recording sheet S on which the toner image is formed to the fixing unit 29, and heats and presses the recording sheet S on the surface of the recording sheet S by the fixing roller 41 and the pressure roller 45 heated by the heater 43. The transferred toner image is melted and fixed on the recording paper S. When there is a next page to be printed, the above process is repeated for that page.

  Next, the operation of the print jam processing of the color laser printer 20 will be described. FIG. 3 is a flowchart of a print jam processing control routine executed by the CPU 12 of the controller 11. This routine is stored in the ROM 13 and executed by the CPU 12 at a predetermined timing after the color laser printer 20 is activated. When the routine of FIG. 3 is started, the CPU 12 determines whether or not a jam has occurred in the conveyance path of the recording paper S (step S100). Here, the occurrence of the jam is performed based on the output values of the recording paper sensors 34a, 34b, and 34c. First, an on / off output timing of each of the recording paper sensors 34a, 34b, and 34c when the recording paper S is normally conveyed is obtained in advance by experience. In actual printing, for example, when the downstream recording paper sensor 34b does not output at a predetermined timing obtained after the recording paper sensor 34a is turned on, it can be determined that a jam has occurred. Further, for example, when the recording paper sensor 34a does not output OFF even after the time required for the recording paper S to pass after the recording paper sensor 34a is turned on, it can be determined that a jam has occurred. . The predetermined timing and the time required for the recording paper S to pass may be set including an error when a paper slip occurs.

  Now, in step S100, when a jam has not occurred in the transport path, the CPU 12 ends this routine as it is, and when a jam has occurred in the transport path, the printing is stopped and the transport of the recording paper S is stopped. (Step S110), it is determined whether or not the jam occurrence position is between the transfer roller pair 30 and the fixing roller pair 40 (predetermined range) (Step S120). Here, the occurrence position of the jam is grasped based on the output values of the recording paper sensors 34a, 34b, and 34c. FIG. 4 is an explanatory diagram of a jam of the recording paper S. If none of the recording paper sensors 34a, 34b, and 34c output an off signal after the recording paper sensors 34a, 34b, and 34c output an on-state for the current jam occurrence position, the recording paper S is It can be seen that there is a jam between the transfer roller pair 30 and the fixing roller pair 40 sandwiched between the transfer roller pair 30 and the fixing roller pair 40 (see FIG. 2). If the downstream recording paper sensor 34c does not turn on at a predetermined timing obtained after the recording paper sensor 34b is turned on, the recording paper S is fixed as shown in FIG. Since the roller pair 40 could not be passed, it can be determined that a jam has occurred between the transfer roller pair 30 and the fixing roller pair 40. In the case where the recording paper sensors 34b, 34c are not turned off even after the time required for the recording paper S to pass after all the recording paper sensors 34a, 34b, 34c have been turned on, the recording paper sensors 34b, 34c are not turned off. As shown in (b), since the recording paper S remains at the position where the recording paper sensors 34b and 34c are arranged, it is determined that a jam has occurred between the transfer roller pair 30 and the fixing roller pair 40. be able to. If the recording paper sensor 34b is not turned on, the recording paper S is not conveyed to the position of the recording paper sensor 34b, so it can be determined that a jam has occurred upstream of the transfer roller pair 30. When only the recording paper sensor 34 c does not output OFF, it can be determined that a jam has occurred downstream of the fixing roller pair 40 because the recording paper S has substantially passed the fixing roller pair 40.

  If the jam occurrence position is not between the transfer roller pair 30 and the fixing roller pair 40 in step S120, a message indicating that a jam has occurred other than between the transfer roller pair 30 and the fixing roller pair 40. Is displayed on the display unit 16 (step S130), and this routine is terminated. On the other hand, when the jam occurrence position is between the transfer roller pair 30 and the fixing roller pair 40, the CPU 12 reads the type of the recording sheet S currently being printed stored in the RAM 14 (step S140). It is determined whether or not the type of the read recording sheet S is a predetermined prohibited recording sheet (step S150). Here, the predetermined prohibited recording paper is defined as a paper that may cause a load on the secondary transfer unit 28 and the fixing unit 29 and cause a failure in the color laser printer 20 due to the jam processing. Here, a thick paper or an OHP film that is difficult to bend because the paper is difficult to bend, and an A3 size recording paper that is long and difficult to fit in the space between the transfer roller pair 30 and the fixing roller pair 40 are predetermined. Is designated as prohibited recording paper.

  When the type of the recording sheet S currently being printed is a predetermined prohibited recording sheet in step S150, the CPU 12 prohibits jam processing (step S160), while the type of the recording sheet S currently being printed is a predetermined prohibited type. If it is not recording paper, the CPU 12 performs jam processing (step S170). This jam processing is performed until the recording sheet S is not sandwiched between the transfer roller pair 30 and the fixing roller pair 40 by either the transfer roller pair 30 or the fixing roller pair 40. 30 and the fixing roller pair 40 are controlled.

  Specifically, as shown in FIG. 5, the CPU 12 rotates the transfer roller 31 so that the recording paper S is conveyed downstream, and the rotation switching device 39 switches the rotation direction so that the recording paper S is upstream. The fixing roller 41 is reversely rotated in the C direction so as to be conveyed to the side. Here, when a jam occurs in the state where none of the recording paper sensors 34a, 34b, and 34c is output from off, that is, in a state where the recording paper S is sandwiched between the transfer roller pair 30 and the fixing roller pair 40. When a jam occurs (see FIG. 2), the CPU 12 rotates the transfer roller 31 or the fixing roller 41 on the side that is output OFF from the recording paper sensors 34a and 34c and output OFF after a predetermined time has elapsed. The operation is stopped depending on whether the electromagnetic clutch of the gear mechanism 38 is disconnected or the driving of the main motor 37 is stopped. Here, the predetermined time is determined as a time for the transfer roller 31 to be transported to a position where the recording paper S is held without being held between the pair of transfer rollers 30 after being output off by the recording paper sensor 34a. The fixing roller 41 is determined as a time during which the recording paper S is conveyed to a position where it is held without being sandwiched between the fixing roller pair 40 after being output off by the recording paper sensor 34c. As a result, as shown in FIG. 5, the recording sheet S is held by these roller pairs 30 and 40 in a state where it is not sandwiched between the transfer roller pair 30 and the fixing roller pair 40. In addition, when a jam occurs in a state where the recording paper sensor 34c is not turned on and the recording paper sensors 34a and 34b are not turned off (see FIG. 4A), the CPU 12 outputs the recording paper sensor 34a after being turned off. After a predetermined time has elapsed, the rotation of the transfer roller 31 is stopped. At this time, although the recording paper sensor 34c is not turned on, there is a possibility that the recording paper S is sandwiched between the fixing roller pair 40. Therefore, the fixing roller 41 is also rotated reversely for a predetermined time. Further, when a jam occurs in a state where the recording paper sensor 34a is turned off and the recording paper sensors 34b and 34c are not turned off (see FIG. 4B), the CPU 12 outputs a predetermined value after the recording paper sensor 34c is turned off. After a lapse of time, the rotation of the fixing roller 41 is stopped. At this time, although the recording paper sensor 34a outputs an off signal, the recording paper S may be sandwiched between the transfer roller pair 30, so the transfer roller 31 is also rotated for a predetermined time. Thus, the recording sheet S is held by at least one of the transfer roller pair 30 and the fixing roller pair 40 in a state where the recording sheet S is not sandwiched between the transfer roller pair 30 and the fixing roller pair 40. Here, it is assumed that the jammed recording paper S is not completely held between the transfer roller pair 30 and the fixing roller pair 40. However, the end of the recording paper S is not affected so that the recording medium is not pulled out. The part may be held.

  After the jam processing at step S170 or after the jam processing is prohibited at step S160, the CPU 12 outputs and displays a message indicating that a jam has occurred between the transfer roller pair 30 and the fixing roller pair 40. This is displayed on the unit 16 (step S180), and this routine is terminated. As shown in FIG. 6, the user who has confirmed this message opens the cover 18 of the portion in which the transfer roller pair 30 and the fixing roller pair 40 are accommodated, and is jammed to transfer the transfer roller pair 30 and the fixing roller pair. The recording sheet S held on at least one of the roller pair 40 is removed.

  Here, the correspondence between the components of the present embodiment and the components of the present invention will be clarified. In this embodiment, the transfer roller pair 30 corresponds to the upstream side conveyance unit of the present invention, the fixing roller pair 40 corresponds to the downstream side conveyance unit and the fixing unit of the present invention, and the CPU 12 detects the jam detection unit and conveyance control. The RAM 14 corresponds to a storage unit, and the recording paper sensors 34a, 34b, 34c correspond to a position detection unit. In this embodiment, an example of the print jam processing method of the present invention is also clarified by explaining the operation of the print jam processing of the color laser printer 20.

  According to the color laser printer 20 of the present embodiment described in detail above, when a jam is detected between the transfer roller pair 30 and the fixing roller pair 40, the recording paper S is fixed to the transfer roller pair 30 and the fixing roller. The transfer roller 31 and the fixing roller 41 are controlled until they are not sandwiched between the roller pair 40 and the transfer roller pair 30 and the fixing roller pair 40 (jam processing). Therefore, the jammed recording paper S can be easily removed as compared with the case where the recording paper S is strongly held between the transfer roller pair 30 and the fixing roller pair 40. At this time, the transfer roller 31 is rotated so that the recording paper S is conveyed downstream, and the fixing roller 41 is rotated so that the recording paper S is conveyed upstream. be able to.

  Further, since the fixing roller pair 40 fixes the toner image and the pressure for pinching the recording paper S is high, the recording paper S is easily jammed, and the user is difficult to pull out the jammed recording paper S. Therefore, it is highly significant to adopt the present invention for the downstream conveying means.

  Further, when the type of the recording paper S currently printed stored in the RAM 14 is a predetermined prohibited recording medium, the recording paper S is placed between the transfer roller pair 30 and the fixing roller pair 40. Since the control for preventing the transfer roller pair 30 and the fixing roller pair 40 from being held between the transfer roller pair 30 and the fixing roller pair 40 is prohibited, the load of the jam processing can be reduced.

  Furthermore, a recording paper sensor 34 for detecting the position of the recording paper S is provided, and the recording paper S is transferred to the transfer roller pair 30 and the fixing roller pair 40 based on the position of the recording paper S detected by the recording paper sensor 34. The transfer roller 31 and the fixing roller 41 are held by the transfer roller pair 30 and the fixing roller pair 40 without being sandwiched between the transfer roller pair 30 and the fixing roller pair 40. In order to control, the jammed recording sheet S can be held between the transfer roller pair 30 and the fixing roller pair 40. Therefore, there is no need for a space for storing jammed recording paper.

  In addition, this invention is not limited to the Example mentioned above at all, and as long as it belongs to the technical scope of this invention, it cannot be overemphasized that it can implement with a various aspect.

  For example, in the above-described embodiment, the controller 11 automatically performs jam processing when detecting jamming of the recording sheet S between the transfer roller pair 30 and the fixing roller pair 40, but the operation unit 17. Is provided with a jam processing permission button for inputting a jam processing permission instruction in advance, and the controller 11 detects a jam of the recording sheet S between the transfer roller pair 30 and the fixing roller pair 40, and this jam processing permission button. Jam processing may be performed when is turned on. In this way, it is possible to perform jam processing in accordance with a user instruction. Alternatively, a jam processing execution button for inputting a jam processing execution instruction is provided on the operation unit 17, and the controller 11 detects a jam of the recording paper S between the transfer roller pair 30 and the fixing roller pair 40 and then performs the printer. When the user presses the jam processing execution button, the jam processing may be executed. If it carries out like this, after a user confirms the condition of jam visually, jam processing can be performed.

  In the above-described embodiment, when the type of the recording sheet S currently being printed is a predetermined prohibited recording sheet, the rotation of the transfer roller 31 and the fixing roller 41 is prohibited and the jam processing is not performed. Alternatively or in addition, a rotation speed sensor that detects the rotation speed of the transfer roller 31 and the fixing roller 41 is provided in each roller, and when the output value of the rotation speed sensor falls below a predetermined threshold during jam processing, That is, the jam processing may be prohibited when the load on the transfer roller 31 and the fixing roller 41 exceeds a certain value. By doing so, it is possible to prevent the color laser printer 20 from being damaged due to excessive load. Here, the predetermined threshold value may be determined as a rotation speed at which a failure may occur in the color laser printer 20 by performing jam processing, for example. Here, the load on the transfer roller 31 and the fixing roller 41 is detected by the rotation speed sensor, but the load on the transfer roller 31 and the fixing roller 41 may be detected by a voltmeter that detects the voltage of the main motor 37.

  Further, in the above-described embodiment, the above-described jam processing is performed on the jam occurring between the transfer roller pair 30 and the fixing roller pair 40. However, the present invention is not limited to this, and other transport rollers are used. Jam processing may be performed on a jam that occurs between the pair and the conveying roller pair. Even in this case, the jammed recording paper S can be easily removed as compared with the case where the recording paper S is strongly held between the pair of conveying rollers.

FIG. 2 is a configuration diagram illustrating an outline of a configuration of a color laser printer 20. FIG. 2 is a configuration diagram showing an outline of configurations of a secondary transfer unit and a fixing unit 29. 6 is a flowchart of a print jam processing control routine of the present embodiment. It is explanatory drawing of jam of the recording paper S of a present Example. It is explanatory drawing of the jam process of the recording paper S of a present Example. It is explanatory drawing of the jam process of the recording paper S of a present Example.

Explanation of symbols

  11 controller, 12 CPU, 13 ROM, 14 RAM, 15 operation panel, 16 display unit, 17 operation unit, 18 cover, 20 color laser printer, 21 charger, 22 photoconductor, 23 exposure unit, 24 developing unit, 24C, 24M, 24Y, 24K toner cartridge, 25 transfer belt, 26 recording paper tray, 27 transport unit, 28 secondary transfer unit, 29 fixing unit, 30 transfer roller pair 31, transfer roller, 32 belt roller, 34a, 34b, 34c Recording paper sensor, 36 drive circuit, 37 main motor, 38 gear mechanism, 39 rotation switching device, 40 fixing roller pair, 41 fixing roller, 41a metal core, 41b rubber layer, 43 heater, 45 pressure roller, 45a shaft 45b Elastic layer, S Recording paper.

Claims (10)

A printer that conveys a recording medium and prints an image on the recording medium,
Upstream transport means for sandwiching the recording medium and transporting the recording medium downstream;
A downstream transport unit disposed downstream of the upstream transport unit and sandwiching the recording medium transported by the upstream transport unit to transport the recording medium downstream;
A jam detecting means for detecting occurrence of a jam of the recording medium between the upstream side conveying means and the downstream side conveying means;
When the jam is detected by the jam detecting means, the recording medium is not substantially held between the upstream conveying means and the downstream conveying means between the upstream conveying means and the downstream conveying means. A transport control means for controlling the upstream transport means and the downstream transport means until
With a printer. When the jam is detected by the jam detection unit, the conveyance control unit is configured such that the recording medium is either the upstream conveyance unit or the downstream conveyance unit between the upstream conveyance unit and the downstream conveyance unit. In addition, the upstream transport unit is controlled so that the recording medium is transported to the downstream side until the recording medium is substantially not pinched, and the downstream transport unit is controlled so that the recording medium is transported to the upstream side. ,
The printer according to claim 1. The printer according to claim 1 or 2,
An instruction acquisition means for acquiring an instruction for jam processing from a user;
The conveyance control unit is configured such that when the jam detection unit detects a jam and the instruction acquisition unit acquires a jam processing instruction, the recording medium is placed between the upstream conveyance unit and the downstream conveyance unit. Controlling the upstream side transport unit and the downstream side transport unit until the upstream side transport unit and the downstream side transport unit are not substantially sandwiched between the upstream side transport unit and the downstream side transport unit,
Printer. The downstream conveying unit is a heat roller type fixing unit that fixes the toner image on the recording medium by heating while conveying the recording medium on which the toner image is transferred.
The printer according to claim 1. The upstream conveying means is a conveying roller that conveys the recording medium while being sandwiched by rollers,
The conveyance control unit is in a state where the recording medium is not substantially sandwiched between the conveyance roller and the fixing unit between the conveyance roller and the fixing unit when a jam is detected by the jam detection unit. The conveying roller is rotated so that the recording medium is conveyed downstream, and the fixing unit is rotated so that the recording medium is conveyed upstream.
The printer according to claim 4. The printer according to claim 1,
Storage means for storing the type of recording medium currently printed,
When the recording medium type stored in the storage unit is a predetermined prohibited recording medium, the conveyance control unit determines whether the recording medium is between the upstream conveyance unit and the downstream conveyance unit. And prohibiting the control so as not to be sandwiched between the upstream conveying means and the downstream conveying means.
Printer. The printer according to claim 1,
Load detecting means for detecting a load for conveying the recording medium of the upstream conveying means and the downstream conveying means;
When the load detected by the load detection unit exceeds a predetermined load value, the conveyance control unit is configured to move the recording medium between the upstream conveyance unit and the downstream conveyance unit between the upstream conveyance unit and the downstream conveyance unit. Prohibiting the control so as not to be sandwiched between any of the downstream side conveying means,
Printer. The printer according to claim 1,
Position detecting means for detecting the position of the recording medium,
The transport control unit is configured to move the recording medium between the upstream transport unit and the downstream transport unit between the upstream transport unit and the downstream transport unit based on the position of the recording medium detected by the position detection unit. Controlling the upstream conveying means and the downstream conveying means so as to be held by at least one of the upstream conveying means and the downstream conveying means in a state of being substantially not sandwiched between any of the conveying means,
Printer. A printing jam processing method by computer software for processing a jam of a recording medium generated when the recording medium is sandwiched and conveyed by an upstream conveying unit and a downstream conveying unit,
(A) detecting the occurrence of jam of the recording medium between the upstream side conveying unit and the downstream side conveying unit;
(B) When the jam is detected in the step (a), the recording medium is positioned between the upstream side transport unit and the downstream side transport unit between the upstream side transport unit and the downstream side transport unit. Also controlling the upstream transport means and the downstream transport means until the state is not substantially pinched,
A printing jam processing method.   A program for causing one or more computers to realize each step of the print jam processing method according to claim 9.

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