JP2016222452A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which can highly reliably prevent the occurrence of breakage and jam even at the time of re-printing after returning conveyance from a stacking of a continuous recording material.SOLUTION: In a printer, with respect to a buffer motor 22 which drives a buffer part 21 controlling the conveyance speed by applying tension to a recording material 11 between a tractor 17 for holding and conveying the continuous recording material 11 having perforations with a set prescribed interval and a heat fixing part 23 for thermally fixing toner on the recording material 11 by holding the recording material 11 between a heat roller 24 and a pressure roller 25 for contact, drive control is performed so as to move the buffer part 21 to any position for deviating from a re-contact position in conjunction with the returning conveyance operation of the recording material 11 by the tractor 17 so that the positions of the perforations do not overlap with the re-contact position between the heat roller 24 and the pressure roller 25 of the heat fixing part 23 on the basis of length information of the recording material 11 at the time of re-printing after returning conveyance from the stacking of the recording material 11 by a control part 35.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a printing apparatus.

  Conventionally, in a printing apparatus such as an electrophotographic laser printer that prints on a continuous recording material such as continuous paper, the recording material is bent by controlling the heating and fixing unit so as not to damage the recording material. A function to reduce the occurrence of jams and jams is required.

  As a well-known technology related to this function, the stacker table is lowered while the recording material is returned and transported to control the recording material so as to eliminate excessive load, thereby preventing the recording material from being folded or jammed. A highly reliable “printing apparatus” (see Patent Document 1) is available.

  In the technique according to Patent Document 1 described above, the stacker table is lowered during return conveyance for the purpose of preventing the recording material from being folded or jammed, and can be returned without applying an extra load to the recording material during return conveyance of the recording material. In this control function, when the printing is stopped, the nip between the heating roller and the pressure roller of the heat fixing unit near the perforation of the recording material can be suppressed. At the time of reprinting after the contact is released, the perforation is less likely to break due to the ironing effect caused by the re-nip of the heating roller and pressure roller near the perforation. There is a problem that folding failure and jamming easily occur due to folding.

  That is, according to the technique of Patent Document 1, the stacker table is lowered when the recording material is returned and conveyed, thereby improving the folding property of the recording material at the perforation and applying an extra load to the recording material by folding the stacking. However, there is an advantage that it is possible to prevent jamming due to bending, but with such a control function, the position of the perforation may overlap the re-contact position by the heating roll and the pressure roll of the heat fixing unit. Since there is a problem that it is difficult to fold the recording material at the perforation due to the ironing effect that occurs when the heating roller and the pressure roller are nipped a plurality of times near the perforation of the recording material at the time of reprinting. There is room for improvement in terms of the basic function that it is not possible to reliably prevent the occurrence of folding and jamming during reprinting after returning from stacking.

  The present invention has been made in order to solve such problems, and its technical problem is that it is reliable to prevent the occurrence of folding and jamming even during reprinting after returning and transporting from a continuous recording material stacking. An object of the present invention is to provide a printing apparatus that can prevent the above.

  In order to achieve the above technical problem, the first means of the present invention is to convey a continuous recording material having a perforation at a predetermined interval, fold it at the perforation and stack it, and return the recording material. In a printing apparatus capable of reprinting, the recording material is sandwiched between the tractor transporting means for holding and transporting the set recording material and the heating roller and the pressure roller, and the recording is performed. A heat fixing means for thermally fixing toner on the material, a buffer means for controlling the conveying speed by applying tension to the recording material between the tractor conveying means and the heat fixing means, and a sewing machine based on the length information of the recording material. The buffer means is moved to any position in conjunction with the return conveyance operation of the recording material by the tractor conveyance means so that the eye position does not overlap with the recontact position by the heating roll and pressure roll of the heat fixing unit. Allowed to be characterized by and a control means for shifting from the re-contact position.

  According to the printing apparatus of the present invention, with the above-described configuration, it is possible to reliably prevent the occurrence of middle folding or jamming even during reprinting after returning and transporting from a continuous recording material stacking. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

FIG. 3 is a schematic diagram illustrating a main configuration of the electrophotographic printing apparatus according to the first exemplary embodiment of the present invention when the recording material is conveyed and returned. FIG. 2 is a schematic diagram illustrating a transfer or heat fixing functional unit and its peripheral functional units in the main configuration of the printing apparatus illustrated in FIG. 1. The state in which the perforation of the recording material overlaps with the contact point between the heating roller and the pressure roller in the heating and fixing unit without changing the position by the buffer unit when the recording material is returned and conveyed in the main part configuration shown in FIG. It is the schematic shown for this purpose. The position of the recording material perforation overlaps the contact point between the heating roller and the pressure roller in the heat fixing unit by changing the position by the buffer unit applied in the embodiment when the recording material is returned and transported in the main part configuration shown in FIG. It is the schematic shown in order to demonstrate a mode that it shifts. It is the schematic which showed the detailed structure of the buffer part contained in the principal part structure shown in FIG. It is the schematic shown in order to demonstrate the detection operation by the buffer part shown in FIG. FIG. 3 is a flowchart illustrating an operation process related to position control of a buffer unit during a recording material returning operation by a control unit included in the main configuration illustrated in FIG. 2.

  Hereinafter, the printing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram illustrating a main configuration of the electrophotographic printing apparatus according to the first embodiment of the present invention when the recording material is returned and conveyed.

  Referring to FIG. 1, in this printing apparatus, the surface of the photosensitive drum 13 is applied by applying a laser beam R emitted from the optical unit 12 to the photosensitive drum 13 uniformly charged by the charger 14. An electrostatic latent image is formed thereon, and toner is attracted to the photosensitive drum 13 from the developing device 15, and a continuous recording material (so-called continuous paper) 11 having perforations at a predetermined interval is set as a hopper 16. Then, the toner is conveyed by the tractor 17 and pressed against the photosensitive drum 13 by the retractor 18, and the toner on the photosensitive drum 13 is transferred onto the recording material 11 by the transfer device 19. Incidentally, the tractor 17 is provided in a pair so as to sandwich the retractor 18, and is driven by the driving force of the tractor motor 20 via a belt spanned between each driving side roller and a roller attached to the driving shaft of the tractor motor 20. In this mechanism, the conveyance drive to the recording material 11 is promoted. That is, the tractor 17 and the retractor 18 here function as tractor transporting means for holding and transporting the recording material 11 set in cooperation.

  In this printing apparatus, the recording material 11 to which toner is attached is sent from the tractor 17 through the buffer unit 21 to a heat fixing unit (which may be called a fixing unit) 23. The buffer unit 21 is attached at one end to the drive shaft of the buffer motor 22 and supports the recording material 11 conveyed at the other end. The heat fixing unit 23 mainly includes a heating roller 24 and a pressure roller 25, and the toner on the recording material 11 is fixed by the pressure roller 25 pressing the recording material 11 against the heating roller 24. . That is, the heat fixing unit 23 functions as a heat fixing unit that heats and fixes the toner on the recording material 11 by sandwiching the recording material 11 between the heating roller 24 and the pressure roller 25.

  The recording material 11 discharged from the heat fixing unit 23 is sandwiched between the driving roller 26 and the driven roller 27 and sent to the swing fin 28 having one end attached to the drive shaft of the swing fin motor 29. The recording material 11 discharged by receiving a swinging operation from the other end side of the swing fin 28 is easily folded at a perforation, and then a member of the paddle 31 whose one end side is coupled to the drive shaft of the pair of paddle motors 30. The driving force of the table motor 33 is passed through a timing belt 34 that spans between a roller attached to the drive shaft of the table motor 33 and a roller provided on the stacker table 32. Are stacked on the stacker table 32 having a mechanism capable of moving in the vertical direction.

  That is, the recording material 11 here swings from the paddle 31 driven by the paddle motor 30 when it is discharged from the swing fin 28 swinged by the swing fin motor 29 and stacked on the stacker table 32. The perforated lines are pressed onto the stacker table 32 in response to the contact force and are deposited on the stacker table 32 in a state where the perforations are easily folded.

  FIG. 2 is a schematic diagram illustrating a transfer or heat-fixing functional unit and its peripheral functional units in the main configuration of the printing apparatus according to the embodiment.

  Referring to FIG. 2, here, the recording material 11 is held by a tractor 17 driven by a tractor motor 20, and the toner on the photosensitive drum 13 is transferred to the recording material 11 at a transfer point P by a transfer device 19. After that, when sent to the heat fixing unit 23 through the buffer unit 21, the other end side of the buffer unit 21 positioned between the tractor 17 that conveys the recording material 11 and the heat fixing unit 23 is a buffer by the control unit 35. It shows a state in which it is moved under the control of the driving force of the motor 22 and the speed difference between the heat fixing unit 23 and the tractor 17 is corrected according to the position during conveyance.

  More specifically, the driving force of the buffer motor 22 is controlled so that the other end side of the buffer unit 21 is usually located near the two-dot chain line portion in FIG. The rotational speed of the heating roller 24 is changed depending on the position so that the speed of the recording material 11 at the tractor 17 and the heat fixing unit 23 is matched, for example, moved to the solid line portion, and then the heating roller 24 and the heating roller 24 in the heat fixing unit 23 are added. The recording material 11 is brought into contact with the pressure roller 25 at a contact point N, and heat and pressure are applied to fix the toner on the recording material 11. That is, the buffer unit 21 functions as a buffer unit that applies a tension to the recording material 11 between the tractor 17 and the heat fixing unit 23 to control the conveyance speed. When such electrophotographic printing is stopped, the heating roller 24 and the pressure roller 25 are moved until the perforation on the front side of the heating roller 24 reaches the contact point N so as not to cause a defect such as a missing character due to a fixing failure. The recording material 11 is conveyed while being in contact with the recording medium 11.

  Thereafter, the perforation of the recording material 11 is controlled to stop at the position of the contact point N, and the contact maintenance is released (nip release) at the position of the perforation. This is because the position of the perforation of the recording material 11 is a print-inhibited region, and character separation does not occur by releasing the contact maintenance at the perforation of the recording material 11. After canceling the contact maintenance, the recording material 11 is returned and conveyed in the direction of the photosensitive drum 13, and the perforation is returned to the vicinity of the transfer point P to prepare for the next transfer operation. At this time, since the distance from the transfer point P to the contact point N is constant, the return amount varies depending on the length of the recording material 11 (the length between the folding perforations). For example, if the distance from the transfer point P to the contact point N is 16 inches and the length of the recording material 11 is 11 inches, the return amount is 5 inches (16-11 = 5). Since the perforation of the recording material 11 on the writing side is always the same place (because the exposure point and the transfer point P of the photosensitive drum 13 are determined), depending on the length of the recording material 11, the recording material at the time of reprinting 11 perforations may be near the contact point N. As described above, when the perforation of the recording material 11 at the time of reprinting is near the contact point N, it becomes difficult to fold the recording material 11 at the perforation due to the ironing effect. As described above, there is a problem of causing the occurrence of.

  In view of this, the printing apparatus according to the embodiment pays attention to the fact that the distance from the transfer point P to the contact point N can be changed by changing the position of the buffer unit 21 at the time of reprinting. It is a technical problem to reliably prevent the occurrence of folding and jamming even during reprinting after returning from stacking. In order to obtain such a function, the control unit 35 in FIG. 2 controls the drive of the buffer motor 22 at the time of reprinting after the recording material 11 is returned and conveyed, based on the length information (one page) of the recording material 11. The buffer unit 21 is moved to an arbitrary position in conjunction with the return conveyance operation of the recording material 11 by the tractor 17 so that the position of the perforation does not overlap the recontact position by the heating roll 24 and the pressure roll 25 of the heat fixing unit 23. What is necessary is just to make it function as a control means to move and shift from a re-contact position.

  FIG. 3 shows a contact point between the perforation of the recording material 11 and the heating roller 24 and the pressure roller 25 in the heat fixing unit 23 without changing the position by the buffer unit 21 when the recording material is returned and transported in the main part configuration described above. It is the schematic shown in order to demonstrate a mode that N overlaps.

  Referring to FIG. 3, it is assumed here that the distance from the transfer point P to the contact point N is 16 inches, and the length of the recording material 11 (paper length) is 8 inches. At the time of stopping, if there is data on two pages of the recording material 11 on the side of the heat fixing unit 23 with the second perforation 2 as a boundary, and printing is stopped if the opposite side to the heat fixing unit 23 is a blank paper portion Then, the recording material 11 is conveyed by one page while being in contact with the heating roller 24 and the pressure roller 25 of the heat fixing unit 23 so that an unfixed portion does not occur in order to prevent missing characters. After fixing for one page, the pressure roller 25 is in a state B indicating release of contact from the heating roller 24.

  Thereafter, the recording material returning operation is performed again in preparation for printing, the leading perforation (perforation 2) of the blank portion of the recording material 11 is returned to the vicinity of the transfer device 19, and the recording material 11 is heated by the heating roller 24 and the heating roller 24. A contact is made between the pressure rollers 25 and the printing operation starts.

  At the time of re-printing after such recording material returning conveyance, as described above, the distance between the transfer point P and the contact point N and the length of the recording material 11 is an integral multiple of the length (the integral multiple of the folding perforation). In the printing, stop, and reprinting process, the contact is released and recontacted in the vicinity of the perforation, and the perforation rigidity of the recording material 11 increases due to the ironing effect. The folding failure due to the middle breakage of the material 11 is likely to occur. As a countermeasure against the occurrence of such a folding failure, a method of increasing the return amount of the recording material 11 is conceivable. However, simply increasing the return amount of the recording material 11 simply causes the sewing machine of the transfer point P related to the transfer device 19 to be. In such a case, the exposure timing and the transfer timing may be shifted, which is not preferable because significant improvements including control settings are required.

  FIG. 4 shows the perforation of the recording material 11 and the heating roller 24 and the pressure roller 25 in the heat fixing unit 23 by changing the position by the buffer unit 21 applied in the embodiment when the recording material is returned and transported in the main part configuration described above. It is the schematic shown in order to demonstrate a mode that the overlap with the contact point N between is shifted.

  Referring to FIG. 4, it is assumed here that the distance from the transfer point P to the contact point N is 16 inches, and the length of the recording material 11 (paper length) is 8 inches. At the time of stoppage, as in the case described with reference to FIG. 3, data exists on two pages of the recording material 11 on the side of the heat fixing unit 23 with the second perforation 2 as a boundary, and the opposite side to the heat fixing unit 23 is blank paper. If it is a part, the recording material 11 is in contact with the heating roller 24 and the pressure roller 25 of the heat fixing unit 23 for one page so that when the printing is stopped, an unfixed part is not generated to prevent missing characters. After the sheet is conveyed and fixed for one page of the length of the recording material 11, the pressure roller 25 enters a state B indicating release of contact from the heating roller 24.

  Thereafter, the recording material returning operation is made again to prepare for printing. At this time, the position of the buffer unit 21 indicated by a two-dot chain line in FIG. 2 is usually moved and fixed so as to be a solid line position. Then, the recording material 11 is returned to the transfer point P side more than usual by the buffer unit 21 that has been moved to a C state. Therefore, when the next printing operation is started, the re-contact position between the heating roller 24 and the pressure roller 25 of the heat fixing unit 23 is normal (the state C in FIG. 3 near the perforation is compared). Unlike the recording material 11, the recording material 11 is shifted to a position avoiding the perforation, and without causing an excessive load near the perforation of the recording material 11, it is possible to stably prevent the occurrence of bending and jamming. Reprinting is performed.

  FIG. 5 is a schematic diagram showing a detailed configuration of the buffer unit 21 described above. Referring to FIG. 5, the buffer unit 21 has a function in which one end side of the sensor plate 37 is attached to the rotating shaft 21 a with a torsion coil spring 38 interposed, and the other end side of the sensor plate 37 is detected by the sensor 40. And one end of the torsion coil spring 38 abuts on the pin 39 on the sensor 40 side, and the other end abuts on the pin on the main body side.

  The buffer portion 21 having such a structure is in contact with the stopper pin 36 by the repulsive force of the torsion coil spring 38 when the recording material 11 is not set and is not applied, and a tension is applied to the recording material 11 during printing. The position of the buffer unit 21 is displaced by the change in the tension of the recording material 11 due to the difference in speed between the tractor 17 and the heat fixing unit 23 during printing. The inclination of the buffer unit 21 is detected.

  Upon receiving this detection result, the control unit 35 determines whether the conveyance speed of the recording material 11 during printing is increasing or decreasing, and then various motors (tractor motor 20, buffer motor 22, swing fin motor 29). And the rotational speed of the heating roller 24 and the pressure roller 25 in the heat fixing unit 23 is changed.

  FIG. 6 is a schematic diagram for explaining the detection operation by the buffer unit 21 described above. Referring to FIG. 6, here, the sensor structure of the part that drives the buffer unit 21 is shown, and the other end side of the sensor plate 37 attached to the rotating shaft 21a is cut into a plurality of cutout detection units 40a. The notch detection unit 40a is arranged so as to be hooked on the detection part of the sensor 40.

  In the buffer unit 21, a plurality of cutout portions in the cutout detection unit 40 a are turned on and off depending on the displacement position, and the current combination is turned on and off in the cutout detection unit 40 a serving as the sensor detection portion. The position of the buffer unit 21 (the inclination of the buffer unit 21) can be detected. For this reason, even when changing the position of the buffer unit 21 by changing the driving force of the buffer motor 22 by the drive control of the control unit 35, up to which position the buffer unit depends on the combination of ON and OFF in the notch detection unit 40a. It is possible to control whether 21 is moved. Incidentally, when the position of the buffer unit 21 is changed by controlling the driving force of the buffer motor 22 by the control unit 35 here, it is possible to set an arbitrary position, and the intention of the operator of the printing apparatus. It is also possible to adjust the position of the buffer unit 21 by instructing.

  FIG. 7 is a flowchart showing an operation process related to the position control of the buffer unit 21 during the recording material returning operation by the control unit 35 described above.

  Referring to FIG. 7, in the operation process related to the position control of the buffer unit 21, when the recording material length is set on the assumption that the recording material 11 is first set in the printing apparatus, the recording material 11 of the set recording material 11 is set. Based on the length information, it is determined whether or not the difference between the distance between the transfer point P and the contact point N and the recording material length is within a range of ± 0.5 inches (step S1). If the result of this determination is within the range of ± 0.5 inches, the position of the buffer unit 21 is changed after returning the recording material (step S2), and the buffer is interlocked with the recording material returning operation by the tractor 17 when printing is stopped. After changing the position of the unit 21, the mode shifts to the position fine adjustment mode (step S3) of the buffer unit 21, but if it is not within the range of ± 0.5 inches, normal control (no change of the position of the buffer unit 21) is performed. The process proceeds to processing (step S4). Here, the change amount of the position of the buffer unit 21 is a change amount of the position that matches the recording length in advance so that the position of the buffer unit 21 becomes an arbitrary position depending on the set length of the recording material 11 (recording material length). Is stored in a storage unit in a table format, and the position change amount is automatically set by the control unit 35. In this case, the recontact position is a position as shown in the D state in FIG. 4, and the heating roller 24 and the pressure roller 25 are contacted twice (double nip) near the perforation of the recording material 11. Therefore, the occurrence of poor folding can be prevented. In addition, the position of the buffer unit 21 is automatically changed by returning the recording material when printing is stopped, but by adding a position fine adjustment mode (step S3) of the buffer unit 21 again, a re-contact point (fixed) This has the effect of preventing character thickening at the location. For example, in the case where fine characters or numbers are written at the re-contacted part, and when it is desired to suppress the thickening of the character as much as possible, the position can be adjusted by controlling the buffer unit 21 by several millimeters in the position fine adjustment mode. Can be shifted.

  Further, in the above-described processing (step S4) of normal control (no change in the position of the buffer unit 21), the normal control is performed, and the position of the buffer unit 21 is not changed. The process proceeds to (Step S5) to prepare for a case where the re-contact position is intentionally shifted, and then the process proceeds to the position change (Step S2) of the buffer unit 21 after returning the recording material. The fine position adjustment mode (step S3) is performed. Incidentally, in the position change mode (step S5) of the buffer unit 21, for example, the position of the buffer unit 21 is controlled to be adjusted within 0.5 inch, and the adjustment value is obtained by changing the shape of the sensor plate 37. It becomes possible to make it fine.

  That is, the control unit 35 described above has a function of automatically changing and setting the position of the buffer unit 21 when the recording material 11 is returned and conveyed by the tractor 17 according to the set length of the recording material 11, and recording by the tractor 17. It has a function of finely adjusting the position of the buffer portion 21 when the material 11 is returned and conveyed.

  In the printing apparatus according to the embodiment described above, the recording material is arranged between the tractor 17, the heating roller 24, and the pressure roller 25 that holds and conveys the continuous recording material 11 having a perforation at a set predetermined interval. A buffer motor 22 that drives a buffer unit 21 that controls the conveyance speed by applying tension to the recording material 11 between the heat fixing unit 23 and the heat fixing unit 23 that thermally contacts the toner on the recording material 11 with the toner 11 sandwiched between them; The position of the perforation is re-contacted by the heating roller 24 and the pressure roller 25 of the heat fixing unit 23 based on the length information of the recording material 11 at the time of reprinting after the recording material 11 is returned from the stacking by the control unit 35. In order not to overlap the position, drive control is performed so as to move the buffer unit 21 to an arbitrary position in conjunction with the return conveyance operation of the recording material 11 by the tractor 17 so as not to move from the recontact position. Sutame, so the occurrence of the center-folding and jam even reprint after conveyance returning from sequential stacking of the recording material 11 can be reliably prevented.

  In addition, since the detail of the principal part structure in the printing apparatus demonstrated in the Example can be variously changed, the printing apparatus of this invention is not limited to the thing of the form disclosed and demonstrated in the Example.

11 Recording material (paper)
DESCRIPTION OF SYMBOLS 12 Optical unit 13 Photoconductor drum 14 Charger 15 Developing machine 16 Hopper 17 Tractor 18 Retractor 19 Transfer device 20 Tractor motor 21 Buffer part 21a Rotating shaft 22 Buffer motor 23 Heating fixing part 24 Heating roller 25 Pressure roller 26 Drive roller 27 Follower Roller 28 Swing fin 29 Swing fin motor 30 Paddle motor 31 Paddle 32 Stacker table 33 Table motor 34 Timing belt 35 Control unit 36 Stopper pin 37 Sensor plate 38 Torsion coil spring 39 Pin 40 Sensor 40a Notch detection unit

JP 2009-132487 A

Claims (3)

In a printing apparatus capable of transporting a continuous recording material having a perforation at a predetermined interval, folding the perforation at the perforation, stacking, and reprinting by transporting the recording material back,
A tractor transporting means for holding and transporting the set recording material, and heat fixing for thermally fixing the toner on the recording material by contacting the recording material between a heating roller and a pressure roller. Means, buffer means for controlling the conveying speed by applying tension to the recording material between the tractor conveying means and the heat fixing means, and the position of the perforation based on the length information of the recording material The buffer means is moved to an arbitrary position in conjunction with the return conveyance operation of the recording material by the tractor conveyance means so as not to overlap the recontact position by the heating roll and the pressure roll of the heat fixing unit. And a control means for shifting from the re-contact position. The printing apparatus according to claim 1.
The printing apparatus has a function of automatically changing and setting the position of the buffer unit when the recording material is returned and conveyed by the tractor conveying unit according to the set length of the recording material. The printing apparatus according to claim 2, wherein
The printing apparatus has a function of finely adjusting the position of the buffer means when the recording material is returned and conveyed by the tractor conveying means.