JP2009113935A - Printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform switching back in a printing apparatus without separately providing a space for the switching back of printing paper, in the printing apparatus for switching back the printing paper. <P>SOLUTION: This printing apparatus includes a paper ejection table receiving printing paper discharged from a paper ejection port by an upper surface and having a shape partially protruding from a main body and reverses front and rear sides of the printing paper by switching back the printing paper. In the printing apparatus, a space for forming a part of a conveying passage for switching back in the paper ejection table is provided. The space is covered so that the printing paper during conveying may not be taken out. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printing apparatus, and more particularly to a printing apparatus that switches back printing paper.

  As a method for automatically reversing the printing paper in a printing apparatus that performs double-sided printing, a method of providing a switchback path in a path for circulating the printing paper and reversing the front and back by switching back the printing paper is widely used. Yes.

Japanese Patent Application Laid-Open No. 2004-228561 describes that a paper discharge tray can have a paper reversing function so that face-up paper discharge and face-down paper discharge can be selected.
JP-A-8-310707

  Since the switchback path needs to correspond to the maximum length of printing paper supported by the printing apparatus, if the switchback path is provided inside the printing apparatus, the casing of the printing apparatus becomes correspondingly large. There is a problem that it ends up.

  To avoid this, it is conceivable to use the outside of the printing device as a space for switchback using the paper discharge port, but the user accidentally pulls out the print paper that is being switched back as printed paper. There is a risk that. Another problem is that during printing paper switchback processing, other printed sheets cannot be discharged from the paper discharge port, resulting in a decrease in printing speed. For this reason, it is not preferable to use the external space of the printing apparatus as a switchback space.

  Since the invention described in Patent Document 1 conveys printing paper in one direction in order to reverse the printing paper at the time of paper discharge, it cannot be applied to the switchback operation at the time of duplex printing.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a printing apparatus for switching back printing paper so that it can be switched back inside the printing apparatus without providing a space for switching back the printing paper.

  In order to solve the above-described problems, a printing apparatus according to the present invention includes a discharge tray having a shape that protrudes from the main body and receives a print sheet discharged from a discharge outlet on the upper surface, and performs switchback of the print sheet. A printing apparatus that reverses the front and back sides of the printing paper, and a space for forming a part of a switchback conveyance path is provided in the discharge tray, and the space can take out the printing paper being conveyed. It is covered so that there is no. As a specific example, the paper discharge tray has a substantially sealed structure in a normal use state, and printed printing paper is stacked on the upper surface of the paper discharge tray, and a predetermined portion on the main body side of the paper discharge tray. (For example, as shown in FIG. 4, a predetermined region on the lower surface on the main body side) is open. A space for forming a transport path for switching back printing paper transported from the opening is provided inside the paper discharge table. This space has a covered structure and prevents the user from accidentally pulling out the printing paper during the switchback operation. The covered structure is not limited to a substantially sealed structure, and for example, the protruding end portion may be configured to cover the printing paper in the switchback transport path.

  Here, a switchback drive mechanism can be provided on the main body side of the paper discharge table. At this time, the drive mechanism can be a roller, and the both ends of the hole portion of the member that accommodates the roller and is provided with a hole portion for contacting the roller with the printing paper in the sheet conveyance direction. It is preferable to provide an inclined portion for preventing abnormal conveyance.

  An opening / closing mechanism for exposing the switchback transport path can be provided on the lower surface side of the paper discharge tray. As a result, it becomes possible to easily cope with a paper jam in the transport path for switchback. Furthermore, a plurality of rib portions can be provided on the upper surface and the lower surface inside the paper discharge tray in parallel with the conveyance direction of the printing paper.

  According to the present invention, in a printing apparatus that switches back printing paper, switching back can be performed inside the printing apparatus without providing a space for switching back the printing paper.

  Thereby, the increase in the housing | casing by providing the space for switchback separately can be prevented. In addition, it is possible to prevent the user from accidentally pulling out the printing paper during the switchback operation from the printed paper. Furthermore, since other printed sheets can be discharged from the discharge port during the print sheet switchback process, it is possible to prevent a decrease in printing speed.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of a printing paper conveyance path of a printing apparatus 100 according to the present invention. As shown in the figure, reference numeral 100 denotes a side feeding table 120 exposed outside the side of the casing and a plurality of feeding trays (130a, 130a provided inside the casing) as a feeding mechanism for supplying printing paper. 130b, 130c, 130d). A paper discharge port 140 is provided as a paper discharge mechanism for discharging printed printing paper.

  In the present embodiment, the printing apparatus 100 includes a plurality of print heads extending in the paper width direction and formed with a large number of nozzles, and ejects black or color ink from each print head to perform printing in line units. However, the present invention is not limited to this method, and can be applied to other printing methods. For example, a printing apparatus such as a serial ink jet method or a laser method may be used.

  Printing paper fed from one of the side paper feed tray 120 and the paper feeding tray 130 is conveyed along a paper feeding system conveyance path FR in the housing by a driving mechanism such as a roller, and the printing paper It is guided to the resist portion R which is the reference position of the head portion. A head unit 110 having a plurality of print heads is provided further on the registration direction R in the transport direction side. The printing paper is image-formed line by line with the ink ejected from each printing head while being conveyed at a predetermined speed by the conveying belt 160 provided on the opposite surface of the head unit 110.

  The printed printing paper is further conveyed in the housing by a driving mechanism such as a roller. In the case of single-sided printing in which printing is performed only on one side of the printing paper, the paper is guided to the paper discharge port 140 and discharged as it is, and the print surface is lowered to a paper discharge table 150 provided as a receiving tray for the paper discharge port 140. It will be loaded. The paper discharge table 150 has a tray shape protruding from the housing, and has a certain thickness.

  In the case of double-sided printing in which printing is performed on both sides of the printing paper, the front side (the first printed side is “front side” and the next printed side is “back side”) is not guided to the paper discharge outlet 140 at the end of printing. In addition, it is transported in the housing. For this reason, the printing apparatus 100 includes a switching mechanism 170 for switching the conveyance path for backside printing. The printing paper that has not been discharged by the switching mechanism 170 is drawn into the switchback path SR and is switched back, so that the front and back are reversed with respect to the transport path. Then, it is guided again to the registration portion R via the switching mechanism 172 by a driving mechanism such as a roller, and the back side is printed by the same procedure as that for the front side. The printing paper on which the back side is printed and images are formed on both sides is guided to the paper discharge port 140 and discharged, and is stacked on a paper discharge table 150 provided as a receiving platform for the paper discharge port 140. .

  Here, in the present embodiment, switchback at the time of duplex printing is performed using a space provided in the paper discharge tray 150. The space provided in the paper discharge tray 150 is configured to be covered so that the printing paper cannot be taken out from the outside at the time of switchback. As a result, it is possible to prevent the user from accidentally pulling out the printing paper during the switchback operation. <A NAME="OLE_LINK2"> <A NAME="OLE_LINK1"> The paper discharge tray 150 is originally provided in the printing apparatus 100, and is switched back using the space in the paper discharge tray 150. This eliminates the need for a separate switchback space in the printing apparatus 100. Therefore, an increase in the size of the housing can be prevented. Further, since the paper discharge port and the switchback path are not shared, the switchback process and the paper discharge of other sheets can be performed in parallel.

  In the printing apparatus 100, one-side printed printing paper is also transported to the registration portion R, which is the reference position of the leading portion of the fed printing paper, during duplex printing. For this reason, a junction point where the transport path of the fed printing paper and the path through which the back-side printing paper is circulated is joined immediately before the registration portion R.

  Based on this merging point, the path on the paper feed mechanism side is referred to as a paper feed system transport path FR, and the other path is referred to as a circulation system transport path CR. FIG. 2 is a diagram schematically showing the paper feed system transport path FR and the circulation system transport path CR.

  In the paper feed system conveyance path FR, a side paper feed driving unit 220 for feeding paper from the side paper feed tray 120 and a tray for feeding paper from the paper feed trays (130a, 130b, 130c, 130d). 1 drive unit 230a, tray 2 drive unit 230b... Are provided. Each drive unit is provided with a drive mechanism composed of a plurality of rollers or the like, and takes in the print sheets stacked on the sheet feed tray or the sheet feed tray one by one and conveys them in the direction of the registration unit R. Each drive unit can be driven independently, and a necessary drive unit operation is performed according to a paper feed mechanism that feeds paper.

  In addition, a plurality of conveyance sensors are arranged in the paper feeding system conveyance path FR so that a conveyance jam in the paper feeding system conveyance path FR can be detected. Each conveyance sensor is a sensor for detecting the presence or absence of printing paper or the leading edge of the printing paper. For example, a plurality of conveyance sensors are arranged at appropriate intervals on the conveyance path, and the conveyance sensor provided on the paper feeding side performs printing. If the conveyance sensor on the conveyance direction side does not detect the print sheet within a predetermined time after the detection of the sheet, it can be determined that a conveyance jam has occurred. Also, a conveyance sensor is provided in the vicinity of the sheet feeding unit. If the conveyance sensor does not detect a print sheet within a predetermined time after driving the side sheet feeding driving unit 220, the tray 1 driving unit 230a, etc., a conveyance jam (feeding error) ) Has occurred.

  By disposing the conveyance sensor corresponding to each sheet feeding unit, not only the occurrence of a conveyance jam in the sheet feeding system conveyance path FR but also the location in the sheet feeding system conveyance path FR is specified. Will be able to.

  In the circulation system conveyance path CR, a registration driving unit 240 that guides printing paper to the registration unit R, a belt driving unit 250 that drives the conveyance belt 160 provided on the opposing surface of the head unit 110, and a conveyance direction side are sequentially arranged. First upper surface transport drive unit 260 and second upper surface transport drive unit 265, upper surface discharge drive unit 270 that guides printed paper to the paper discharge port 140, and pulls the print paper into the switchback path SR for reverse printing and inverts it. And a switchback path driving unit 280 that leads to the merging point. Each drive unit includes a drive mechanism composed of one or a plurality of rollers or the like, and conveys printing paper one by one along the conveyance path. Each drive unit can be driven independently, and a necessary drive unit operation is performed according to the conveyance state of the printing paper.

  Further, a plurality of conveyance sensors are also arranged in the circulation system conveyance path CR so that a conveyance jam in the circulation system conveyance path CR can be detected. In addition, it is possible to confirm that the printing paper is properly conveyed to the registration unit R. In the circulatory system conveyance path CR, a conveyance sensor is provided corresponding to the drive unit, and it is possible to specify in which drive unit of the circulatory system conveyance path CR the conveyance jam has occurred.

  FIG. 3 is a block diagram illustrating a functional configuration of the printing apparatus 100. The printing apparatus 100 includes a main control unit 300 including a CPU, a memory, and the like, and a print control unit 301 and a drive control unit 302 are configured by the CPU operating according to a program stored in the memory. .

  In addition, the printing apparatus 100 includes a printing condition setting unit 310 that receives settings such as duplex / single-sided printing, paper size, and resolution, a conveyance jam detection unit 320 that detects a jam in the conveyance path based on a signal from the conveyance sensor, A display unit 330 that displays information about the printing apparatus is provided. For example, the print condition setting unit 310 accepts print data settings from print data sent from a computer connected to the printing apparatus 100 or a user instruction via an input panel (not shown).

  The print control unit 301 generates image data according to the printing conditions received by the printing condition setting unit 310, and controls the printing process in the print execution unit 340 configured by a printing mechanism such as a print head. The drive control unit 302 operates each of the above-described drive units under the control of the print control unit 301 to carry the printing paper.

  FIG. 4 is a view showing the structure of the paper discharge tray 150 having a switchback space therein. As shown in the drawing, the paper discharge tray 150 is a paper discharge tray transport that includes a paper discharge tray main body 151 on which the discharged print sheets are stacked, a paper discharge tray lower portion 152, and a switchback roller 154. Part 153. The switchback roller 154 is a driving roller for reciprocally conveying the printing paper along the switchback path SR, and a driven roller 155 is disposed on the opposite side. The printing paper to be switched back is guided into the paper discharge tray main body 151 by the switchback roller 154 of the paper discharge tray transport unit 153, reversed at a predetermined position, and transported to the outside of the paper discharge tray main body 151. In this manner, the discharge tray main body 151 does not require a driving mechanism and can be configured simply.

  The lower part 152 of the paper discharge table can be opened and closed with the shaft portion 1521 as a fulcrum. As a result, when a paper jam or the like occurs in the switchback path SR, the jammed print paper can be easily taken out. By setting the open / close portion to the discharge tray lower portion 152, the jammed print sheet can be taken out without removing the printed sheets stacked on the discharge tray main body 151. In a normal use state, the discharge tray lower part 152 is closed so that the printing paper conveyed through the switchback path SR is not exposed to the outside.

  FIG. 5 is a view of the discharge tray main body 151 as viewed obliquely from below. In the orientation shown in this figure, the switchback path SR side is shown, and the discharged print sheets are stacked on the opposite side. As shown in the drawing, the discharge tray main body 151 is provided with a plurality of rib portions 1511 on the inner surface serving as the switchback path SR in parallel with the paper transport direction. This is because the printing paper to be switched back is only supported by the switchback roller 154 and the driven roller 155 in addition to the reinforcement of the paper discharge tray main body 151, so that the front surface or the back surface is the inside of the paper discharge tray 150. This is to make the contact area as small as possible. In addition, if the rib portion is provided perpendicular to the paper transport direction, the end of the print paper may be caught and bend or hinder the transport, so it is provided in parallel with the transport direction.

  FIG. 6 is a view of <A NAME="OLE_LINK3"> the sheet discharge table lower part 152 as seen obliquely from above. In the direction shown in this figure, the switchback path SR plane side is shown. As shown in the drawing, the discharge tray lower portion 152 is also provided with a plurality of rib portions 1522 on the surface serving as the switchback path SR in parallel with the sheet conveyance direction for the same reason as the discharge tray main body 151. ing. Since the printing apparatus 100 can print on various sizes of printing paper, both the rib portion 1511 of the paper discharge tray main body 151 and the rib portion 1522 of the paper discharge tray lower portion 152 are the centers of the conveyed printing paper. Ribs are arranged symmetrically with respect to the line.

  FIG. 7 is a view of the sheet delivery table transport unit 153 provided with the switchback roller 154 as viewed obliquely from above. In the direction shown in the figure, the switchback path SR side is shown. A plurality of rib portions 1531 are also provided on the surface that becomes the switchback path SR in the paper discharge table transport portion 153 in parallel with the paper transport direction.

As shown in FIG. 7, the discharge tray transport unit 153 is provided with a rectangular roller hole so that the switchback roller 154 is exposed to the switchback path SR and comes into contact with the printing paper. As shown in FIG. 8A, inclined portions 153a and 153b are formed on both sides on the conveyance direction side of the portion serving as the edge of the roller hole of the paper discharge table conveying portion 153. This inclined part is provided to prevent the edge of the printing paper being conveyed from being caught at the edge of the hole for <A NAME="OLE_LINK5"><ANAME="OLE_LINK4"> roller. In SR, the printing paper 500 is conveyed leftward as shown in FIG. 8B, and then reversed and conveyed rightward as shown in FIG. 8C. In addition, inclined portions 153a and 153b are formed. Therefore, even when the printing paper 500 is conveyed in any direction, it can be prevented from being caught at the edge of the roller hole.
For example, depending on the printing paper, the leading edge of the printing paper does not follow the conveyance path and falls into the roller hole due to lack of elasticity, or the printing paper is wound around the roller 154 by electrostatic force, and the discharge tray conveyance unit 153 may collide. In such a case, if the inclined portion is not provided, the printing paper may be caught at the edge of the transport unit 153. In the present embodiment, since the inclined portion is provided, it is possible to prevent the printing paper from being deviated from the transport direction by preventing the printing paper from being caught at the edge. The inclined portion may be provided with a rib for guiding the paper in the conveyance direction, and the inclined surface of the inclined portion prevents the paper from being guided in the conveyance direction or prevents the printing paper from falling into the hole. It may be a curved surface.

  Note that switching back the printing paper is not limited to duplex printing. For example, even during single-sided printing, circulation system CR is circulated for the purpose of drying the ink ejected onto the printing paper, or switching back is performed for the purpose of discharging the printing paper with face-up so that the circulation system transportation path CR is set. It may be circulated. The present invention can also be applied to such processing.

  As described above, according to the present embodiment, in a printing apparatus that switches back printing paper, switching back can be performed inside the printing apparatus without providing a separate space for switching back the printing paper. .

It is a figure which shows the outline | summary of the printing paper conveyance path | route of the printing apparatus which concerns on this invention. It is the figure which showed typically the paper feed system conveyance path and the circulation system conveyance path. FIG. 2 is a block diagram illustrating a functional configuration of a printing apparatus. It is a figure which shows the structure of a paper discharge stand. It is the figure which looked at the discharge stand main-body part from diagonally downward. It is the figure which looked at the discharge stand lower part from diagonally upward direction. It is the figure which looked at the discharge stand conveyance part provided with the switchback roller from diagonally upward. It is a figure which shows the shape of the part used as the edge of the hole for rollers of a discharge stand conveying part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Printing apparatus, 110 ... Head unit, 120 ... Side paper feed stand, 130 ... Paper feed tray, 140 ... Paper discharge outlet, 150 ... Paper discharge stand, 151 ... Paper discharge stand main-body part, 152 ... Lower part of paper discharge stand, 153: Inclining part, 154 ... Switchback roller, 160 ... Conveying belt, 170 ... Switching mechanism, 172 ... Switching mechanism, 300 ... Main control part, 301 ... Print control part, 302 ... Drive control part, 310 ... Printing condition setting part 320 ... conveying jam detection unit, 330 ... display unit, 340 ... print execution unit, 1511 ... rib unit, 1521 ... shaft unit, 1522 ... rib unit, 1531 ... rib unit

Claims (5)

A printing apparatus that receives a print sheet discharged from a discharge port on the upper surface, a discharge stand having a shape protruding partly from the main body, and performs a switchback of the print sheet to reverse the front and back of the print sheet,
The printing apparatus is characterized in that a space for forming a part of a switchback transport path is provided in the discharge tray, and the space is covered so that the printing paper being transported cannot be taken out. The printing apparatus according to claim 1,
A printing apparatus comprising a switchback driving mechanism provided on a main body side of the paper discharge table. The printing apparatus according to claim 2,
The drive mechanism is a roller, and is configured to prevent abnormal conveyance at both edges in the sheet conveyance direction of the hole portion of a member that accommodates the roller and is provided with a hole portion for contacting the roller with printing paper. A printing apparatus comprising an inclined portion. The printing apparatus according to any one of claims 1 to 3,
A printing apparatus, wherein an opening / closing mechanism for exposing the switchback transport path is provided on a lower surface side of the paper discharge table. The printing apparatus according to any one of claims 1 to 4,
A printing apparatus, wherein a plurality of ribs are provided on the upper and lower surfaces inside the paper discharge tray in parallel with the conveyance direction of the printing paper.