JP2019059076A - Printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine a cause of transport failure. SOLUTION: An acceleration time calculation unit 101 for calculating an acceleration time from the start of rotational drive of a transfer roller to reaching a predetermined rotation speed, and an upstream side and a downstream side of the transfer roller on a transfer path among a plurality of paper sensors. Based on the detection result of the paper sensor, the transfer defect detection unit 102 that detects the transfer defect of the transfer roller, and the transfer defect detection unit 102, when the transfer defect is detected, the acceleration time calculation unit 101 calculates the said. A factor determination unit 103 for determining whether the transfer defect of the transfer roller is due to a mechanical factor or a control factor is provided based on the acceleration time of the transfer roller in which the transfer defect is detected. [Selection diagram] Fig. 2

Description

  The present invention relates to a printing apparatus capable of determining the cause of transport failure.

  2. Description of the Related Art Conventionally, a printing apparatus that prints an image while conveying a sheet is known. The printing apparatus is provided with a plurality of conveyance means on the conveyance path, and the conveyance means conveys the sheet at the conveyance timing determined by the control program.

  In a printing apparatus that performs printing while transporting such a sheet, sheet transport failure may occur due to various factors.

  Patent Document 1 discloses an image forming unit that forms an image based on image information on a recording medium transported by a transporting unit, and a transport failure detection unit that detects transport failure of the recording medium at each of a plurality of positions on a transport path. And when the position where the conveyance failure is detected by the conveyance failure detection unit is a predetermined position when confirming the cancellation of the conveyance failure of the recording medium, the state in which the formation of the image based on the image information is stopped Alternatively, the recording medium is conveyed in a state where the number of images to be formed is limited, and when the position where the conveyance failure is detected is other than the predetermined position, the recording medium is conveyed while forming the image based on the image information. There is disclosed a technology related to an image forming apparatus including control means for controlling the transport means and the image forming means.

JP, 2013-20277, A

  Here, the causes of the transport failure mainly include mechanical factors and control factors of the transport means. The mechanical factor includes, for example, wear of the transport roller of the transport means and failure of the motor. Control factors include noise in the control signal and timing failure due to false detection.

  In the image forming apparatus described in Patent Document 1, the processing of the image forming unit is controlled depending on whether or not the position at which the conveyance failure is detected by the conveyance failure detection unit is a predetermined position. I do not guess about the factor.

  For example, when the transport failure is a mechanical factor such as a motor failure, it is necessary to notify the user to repair or replace the failed motor. On the other hand, when the transport failure is a control factor such as noise in the control signal or timing failure due to an erroneous detection, the transportability may be low and the transport failure may occur accidentally. Therefore, in the case of control factors, there have been many user needs to continue printing as much as possible. Therefore, when a transport failure occurs, it has been strongly desired that the user appropriately determine the cause of the transport failure in order to respond appropriately.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a printing apparatus capable of determining the cause of transport failure.

In order to achieve the above object, a first feature of the printing apparatus according to the present invention is
Conveying means for conveying the sheet along the conveyance path by rotationally driving the conveyance roller;
A plurality of sheet detection means for detecting a sheet conveyed by the conveyance means;
Acceleration time calculating means for calculating an acceleration time from the start of rotational driving of the transport roller to reaching a predetermined rotational speed;
And a conveyance failure detection unit that detects a conveyance failure of the conveyance unit based on detection results by the sheet detection unit on the upstream side and the downstream side of the conveyance unit on the conveyance path among the plurality of sheet detection units;
When the conveyance failure is detected by the conveyance failure detection unit, the factor determination is performed to determine the cause of the conveyance failure based on the acceleration time of the conveyance unit in which the conveyance failure is detected calculated by the acceleration time calculation unit. Means,
To provide.

  According to the first aspect of the printing apparatus of the present invention, it is possible to appropriately determine the cause of the conveyance failure.

FIG. 1 is a schematic configuration diagram of a printing apparatus according to an embodiment of the present invention. FIG. 1 is a functional configuration diagram of a printing apparatus according to an embodiment of the present invention. FIG. 6 is an explanatory view schematically illustrating an operation of the CPU of the printing apparatus according to the embodiment of the present invention. It is the flowchart which showed the processing contents by CPU of the printing device which relates to the form of execution of this invention. It is the flowchart which showed the processing contents by CPU of the printing device which relates to the form of execution of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts or components are denoted by the same or equivalent reference numerals throughout the drawings.

  Further, the embodiment shown below is an example of an apparatus etc. for embodying the technical idea of the present invention, and the technical idea of the present invention is the arrangement of each component, etc. Not specific to Various changes can be added to the technical idea of the present invention within the scope of the claims.

<Configuration of Printing Device>
FIG. 1 is a schematic block diagram of a printing apparatus according to an embodiment of the present invention, and FIG. 2 is a functional block diagram of the printing apparatus shown in FIG. In the following description, the front side is the front side of the sheet of FIG. 1 where the user is located. Further, as shown in FIG. 1, the upper, lower, left, and right are the upper, lower, left, and right directions as viewed from the user.

  A path indicated by a thick line in FIG. 1 is a transport path through which a sheet, which is a print medium, is transported. Of the transport paths, the path shown by the solid line is a normal path RC, the path shown by an alternate long and short dash line is a reverse path RR, the path shown by a broken line is an upper sheet discharge path RD1, the straight sheet discharge path RD2, and the path shown by a two-dot chain line It is a route RS. The normal route RC and the reverse route RR constitute a circulation route. In the following description, upstream and downstream mean upstream and downstream in the transport path.

  The printing apparatus according to the present embodiment performs printing based on image data input from a personal computer via a personal computer (not shown) and a communication network.

  The personal computer is a general information processing terminal in which a printer driver program developed corresponding to the printing apparatus 1 is installed.

  As shown in FIGS. 1 and 2, the printing apparatus 1 transports the sheet P along the transport path (the sheet feeding unit 2, the vertical transport unit 3, the transport printing unit 4, and the upper surface transport unit 6). And the upper sheet discharge conveyance unit 7, the reversing unit 9, the straight paper discharge conveyance unit 13), the ink jet head unit 5, the operation panel unit 10, the control unit 11, and a plurality of places on the conveyance path Sheet sensors 27a to 27e, 33a to 33d, 36a to 36f, 38, 43 for acquiring transport information of the sheet P transported by the transport unit, and a housing 12 for storing or holding each part.

  The sheet feeding unit 2 holds the sheet P and feeds a sheet. The sheet feeding unit 2 is provided on the most upstream side of the conveyance path, and includes a side sheet feeding table 21, a side sheet feeding roller 22, a side sheet feeding motor 51, a plurality of internal sheet feeding tables 23, and a plurality of internal sheet feeding tables. A paper roller 24 and an internal paper feed motor 52 are provided.

  The side paper feed tray 21 is used to load the sheets P, and a part of the side paper feed tray 21 is exposed to the outside of the housing 12 of the printing apparatus 1 and installed.

  The side sheet feeding roller 22 is provided on the upper side of the side sheet feeding table 21 and takes out sheets P one by one from the side sheet feeding table 21 and conveys the sheet P toward a registration roller 31 described later along a sheet feeding path RS. Do. The side feed roller 22 is rotationally driven by the side feed motor 51.

  The internal sheet feeding table 23 is provided inside the housing 12 and is configured to be loaded with the sheet P. The internal sheet feeding roller 24 is disposed along any one of the plurality of sheet feeding paths RS between the downstream end of the plurality of internal sheet feeding trays 23 and the vertical sheet feeding roller, and The sheet P stacked on the sheet feeding table 23 is conveyed to the vertical conveyance unit 3. The internal feed roller 24 is rotationally driven by the internal feed motor 52.

  The vertical conveyance unit 3 includes a plurality of pairs of vertical conveyance rollers 25a to 25d, a merging sheet feeding roller 28, a merging sheet feeding motor 53, and sheet sensors 27a to 27e, and the sheet fed from the internal sheet feeding table 23 P is conveyed along the sheet feeding path RS.

  The vertical conveyance rollers 25 a to 25 d are disposed along the sheet feeding path RS, and convey the sheet P toward a merging sheet feeding roller 28 described later. The most downstream side vertical conveyance roller 25 d is configured to be rotationally driven by a side paper feed motor 51 that rotationally drives the side paper feed roller 22. The other vertical conveyance rollers 25 a to 25 c are configured to be rotationally driven by an internal paper feeding motor 52 that rotationally drives the internal paper feeding roller 24.

  Merged sheet feed roller 28 is disposed on sheet feed path RS between vertical conveyance rollers 25 a to 25 d and registration roller 31 of conveyance printing unit 4, and conveys and prints sheet P conveyed from vertical conveyance roller 25. Feed the sheet to section 4. The merging feed roller 28 is rotationally driven by a merging feed motor 53.

  The sheet sensors 27a to 27e are disposed near the downstream side of the vertical conveyance rollers 25a to 25d. The sheet sensors 27a to 27e are applied with an optical sensor having a light emitting element and a light receiving element, and detect the sheet P conveyed along the sheet feeding path RS.

  The conveyance printing unit 4 is disposed downstream of the sheet feeding unit 2 and prints an image while conveying the sheet P. The conveyance printing unit 4 includes a registration roller 31, a registration motor 54, a belt conveyance unit 32, a belt motor 55, and sheet sensors 33a to 33d, and includes a side sheet feeding table 21, an internal sheet feeding table 23, The sheet P conveyed from the reversing unit 9 is conveyed to the upper surface conveyance unit 6.

  The registration roller 31 supplies the sheet P fed from the sheet feeding unit 2 to the belt conveyance unit 32, and refeeds the sheet P conveyed from the reversing unit 9 to the belt conveyance unit 32. The registration roller 31 is disposed on the normal path RC upstream of the transport printing unit 4.

  The registration roller 31 is rotationally driven by a registration motor 54. At this time, the registration roller 31 temporarily stops the sheet P conveyed from the side sheet feeding table 21, the internal sheet feeding table 23, and the reversing unit 9 by the control of the registration motor 54, and performs skew correction. The sheet is sent to the belt conveyance unit 32.

  The belt conveyance unit 32 is disposed downstream of the registration roller 31 in the normal route RC, and conveys the paper P to the downstream side while suctioning the lower surface of the paper P conveyed from the registration roller 31 by the endless belt. Do. The belt conveyance unit 32 conveys the sheet P by driving the belt by the rotational drive of the belt motor 55.

  A suction fan 39 is provided inside the belt conveyance unit 32. A large number of air holes are formed on the surface of the endless belt forming the belt conveyance unit 32, and the sheet P is adsorbed and conveyed by the endless belt by the suction force generated by the rotation of the suction fan 39. The suction fan 39 is rotationally driven by the suction motor 50.

  The sheet sensors 33a to 33d detect the sheet P conveyed along the normal route RC, and detect floating of the sheet P conveyed, and acquire conveyance information. The sheet sensor 33 a is disposed near the upstream side of the registration roller 31. The sheet sensor 33 b is disposed near the downstream side of the registration roller 31. The sheet sensor 33 c is disposed at the upstream portion of the belt conveyance unit 32 downstream of the sheet sensor 33 b. The sheet sensor 33 d is disposed downstream of the inkjet head unit 5.

  Further, the conveyance printing unit 4 includes an encoder 44 a that acquires conveyance information such as a rotation angle measurement of the roller 44 that rotates the belt conveyance unit 32.

  The inkjet head unit 5 is a printing unit that prints on the sheet P conveyed by each conveyance unit, is disposed above the belt conveyance unit 32, and has a plurality of nozzles in a direction substantially orthogonal to the conveyance direction of the sheet P. It has a plurality of line-type inkjet heads (not shown) arranged. The inkjet head unit 5 discharges ink (recording material) from the inkjet head onto the sheet P transported along the normal route RC by the belt transport unit 32 to print an image.

  The upper surface conveyance unit 6 conveys the sheet P conveyed by the belt conveyance unit 32 upward so as to make a U-turn from the right direction to the left direction. The upper surface conveyance unit 6 includes a plurality of pairs of upper surface conveyance rollers 35a to 35f, sheet sensors 36a to 36f, and upper surface motors 58a to 58f that rotationally drive the upper surface conveyance rollers 35a to 35f.

  The upper surface conveyance rollers 35 a to 35 f are disposed along a normal path RC between the conveyance printing unit 4 and the upper sheet discharge conveyance unit 7, and press and convey the sheet P.

The sheet sensors 36a to 36f detect the sheet P conveyed along the normal path RC.
The sheet sensor 36 a is disposed in the vicinity of the upstream side of the most upstream surface conveyance roller 35 a. The sheet sensor 36 b is disposed near the downstream side of the top conveyance roller 35 a. The sheet sensor 36c is disposed between the upper conveyance roller 35b and the upper conveyance roller 35c at the entrance of the lower horizontal portion of the normal route RC. The sheet sensor 36d is disposed between the upper surface conveyance roller 35c and the upper surface conveyance roller 35d adjacent to each other in the lower horizontal portion of the normal route RC. The sheet sensor 36 e is disposed downstream of the upper conveyance roller 35 e in the horizontal portion of the lower area of the normal route RC. The sheet sensor 36 f is disposed in the vicinity of the upstream side of the most downstream upper surface conveyance roller 35 f.

  The straight paper discharge conveyance unit 13 does not convey the sheet P conveyed by the belt conveyance unit 32 to the upper surface conveyance unit 6 but causes the belt conveyance unit 32 to rectilinearly advance from the belt conveyance unit 32 and conveys the paper P to the straight paper discharge stand Discharge the paper. The straight paper discharge conveyance unit 13 includes a switching unit 34, a paper discharge roller 37, a sheet sensor 38, a solenoid 61 that drives the switching unit 34, and a straight paper discharge motor 56 that rotationally drives the paper discharge roller 37. .

  The switching unit 34 is disposed at a branch point between the straight paper discharge path RD2 and the normal path RC, and switches the transport path of the sheet P between the straight paper discharge path RD2 and the normal path RC.

  The paper discharge roller 37 is disposed between the switching unit 34 and the rectilinear paper discharge stand 14, and conveys the sheet P conveyed by the conveyance printing unit 4 along the rectilinear paper ejection path RD2 and advances the paper rectilinearly The sheet is discharged to the tray 14. The paper discharge roller 37 is rotationally driven by the straight paper discharge motor 56.

  The sheet sensor 38 detects the sheet P conveyed along the straight paper discharge path RD2. The paper sensor 38 is disposed between the paper discharge roller 37 and the straight paper discharge stand 14.

  The straight paper discharge tray 14 has a tray shape protruding from the housing 12 and is installed obliquely. Then, the printed paper P conveyed by the straight paper discharge conveyance unit 13 is stacked.

  The upper discharge conveyance unit 7 conveys the printed sheet P to the upper discharge tray 8 and discharges it. The upper sheet discharging / conveying unit 7 includes a switching unit 41, a sheet discharging roller 42, a sheet sensor 43, a solenoid 62 driving the switching unit 41, and an upper sheet discharging motor 57 rotating the sheet discharging roller 42. .

  The switching unit 41 is disposed at a branch point between the upper sheet discharge path RD1 and the reverse path RR, and switches the transport path of the sheet P between the upper sheet discharge path RD1 and the reverse path RR.

  The sheet discharge roller 42 is disposed between the switching unit 41 and the upper sheet discharge table 8 and conveys the sheet P conveyed by the upper surface conveyance unit 6 along the upper sheet discharge path RD1 to discharge the upper sheet. The paper is discharged to the tray 8.

  The sheet sensor 43 detects the sheet P conveyed along the upper sheet discharge path RD1. The sheet sensor 43 is disposed between the sheet discharge roller 42 and the upper sheet discharge table 8.

  The upper sheet discharge tray 8 is disposed at the downstream end of the upper sheet discharge path RD1, and the printed sheets P conveyed by the upper sheet discharge conveyance unit 7 are stacked. The upper sheet delivery table 8 has a tray shape protruding from the housing 12 and is installed at an angle.

  The reversing unit 9 reverses the single-sided printed sheet P and feeds the sheet P to the transport printing unit 4 again during double-sided printing. The reversing unit 9 includes a reversing roller 45, a reversing motor 59, a switchback unit 46, a sheet refeeding roller 47, a sheet refeeding motor 60, a switching gate 48, and sheet sensors 49a and 49b.

  The reversing roller 45 is disposed on the reversing path RR between the uppermost surface conveying roller 35 on the most downstream side and the loading port of the switchback unit 46. Then, the reversing roller 45 temporarily carries the sheet P conveyed by the upper surface conveying unit 6 into the switchback unit 46 and then conveys the sheet P out, and conveys the sheet P to the sheet re-feed roller 47. The reverse roller 45 is rotationally driven by the reverse motor 59 in the forward direction (at the time of loading) and the reverse direction (at the time of unloading).

  The switchback unit 46 is a space for the reverse roller 45 to temporarily carry in the sheet P. The switchback section 46 is formed at the lower part of the upper sheet discharge table 8 and the vicinity of the reversing roller 45 is opened to carry in the sheet P.

  The sheet re-feed roller 47 is disposed on a reverse path RR between the reverse roller 45 and the registration roller 31, and conveys the sheet P conveyed by the reverse roller 45 to the registration roller 31. The sheet re-feed roller 47 is rotationally driven by the sheet re-feed motor 60.

  The switching gate 48 is disposed in the vicinity of the center of gravity at three positions of the upper surface conveyance roller 35, the reversing roller 45, and the refeed roller 47 most downstream. Then, the switching gate 48 guides the sheet P conveyed by the upper surface conveyance roller 35 to the reversing roller 45. Further, the switching gate 48 guides the sheet P conveyed out of the switchback section 46 by the reversing roller 45 to the sheet re-feed roller 47.

  The sheet sensors 49a and 49b detect the sheet P conveyed along the reverse path RR. The sheet sensor 49 a is disposed between the reverse roller 45 and the switchback unit 46, and the sheet sensor 49 b is disposed in the vicinity of the downstream side of the sheet refeed roller 47.

  Hereinafter, the above-described side paper feed roller 22, internal paper feed roller 24, vertical conveyance rollers 25a to 25d, merging paper feed roller 28, registration roller 31, upper surface conveyance rollers 35a to 35f, paper discharge roller 37, paper discharge roller 42, When it is not necessary to distinguish between the reversing roller 45 and the sheet re-feed roller 47, they are collectively referred to as a conveyance roller.

  The operation panel unit 10 has operation buttons, a touch panel, and the like, receives an input operation by the user, and displays various screens and the like.

  As shown in FIG. 2, the control unit 11 performing central control of the printing apparatus 1 includes a sheet feeding unit 2, a vertical conveyance unit 3, a conveyance printing unit 4, an inkjet head unit 5, and an upper surface conveyance unit 6. It controls the straight paper discharge conveyance unit 13, the upper paper discharge conveyance unit 7, the reversing unit 9, and the operation panel unit 10. The control unit 11 includes a CPU 100 for executing various programs, a RAM 111 for temporarily storing each information, a ROM 112 for storing control programs including print control and conveyance control on paper, and the like, and print control And a connection unit 114 for performing input / output and the like. The HDD 113 stores various setting values and the like necessary for executing conveyance control and the like.

  The HDD 113 stores a predetermined detection time for each sheet sensor and a predetermined acceleration time for each conveyance roller. The prescribed detection time refers to a prescribed time required from detection of a sheet P by a sheet sensor to detection by a sheet sensor on the downstream side of the transport path. Further, the specified acceleration time refers to the time from when the rotation of the conveyance roller is started to when it reaches a predetermined conveyance speed (rotational speed).

  Further, the control factor counter K1 and the mechanical factor counter K2 are stored in the HDD 113 for each conveyance roller. Here, the control factor counter K1 is a counter used to determine that the transport failure is a control factor, and the mechanical factor counter K2 is a counter used to determine that the transport failure is a mechanical factor .

  The connection unit 114 electrically connects the control unit 11 to the motor and sheet sensor of each unit. The connection unit 114 receives a detection signal detected by the sheet sensor of each unit and inputs the signal to the CPU 100. Further, the connection unit 114 receives the motor rotation number from the encoder provided in the motor of each unit, and inputs the same to the CPU 100. Furthermore, the control signal generated by the CPU 100 is received and input to the motor of each unit. Thereby, the motor of each part is rotationally driven, or the ink is ejected from the inkjet head unit 5.

  The CPU 100 includes an acceleration time calculation unit 101, a conveyance failure detection unit 102, a factor determination unit 103, a conveyance control setting unit 104, and a notification unit 105.

  FIG. 3 is an explanatory view schematically illustrating the operation of the CPU 100 of the printing apparatus 1 according to the embodiment of the present invention. In FIG. 3, as an example, sheet sensors 36 d and 36 e disposed in the normal route RC in the upper surface conveyance unit 6, upper surface conveyance rollers 35 d and 35 e provided between the sheet sensors 36 d and 36 e, and upper surface conveyance An upper surface motor 58 d for rotationally driving the roller 35 d and an upper surface motor 58 e for rotationally driving the upper surface conveyance roller 35 e will be described as an example.

  The acceleration time calculation unit 101 calculates an acceleration time until the predetermined conveyance speed (rotational speed) is reached after the top surface conveyance rollers 35d and 35e are respectively driven to rotate. Specifically, the acceleration time calculation unit 101 receives the motor rotational speed from the encoder provided to the upper surface motors 58d and 58e, and the time when the upper surface conveyance rollers 35d and 35e start to rotate based on the received motor rotational speed The acceleration time until the predetermined conveyance speed (rotational speed) is reached is calculated, and stored in the RAM 111.

  The conveyance failure detection unit 102 conveys in the conveyance route based on the detection result of the paper sensor 36d provided on the upstream side of the upper surface conveyance rollers 35d and 35e on the normal route RC and the paper sensor 36e provided on the downstream side. Detect the occurrence of defects and stop the transport. Specifically, the conveyance failure detection unit 102 detects a time from when the leading end of the sheet P conveyed on the normal route RC is detected by the sheet sensor 36 d to when the leading end of the sheet P is detected by the sheet sensor 36 e Detect as time. Then, when the detection time exceeds the defined detection time corresponding to the section between the sheet sensor 36d and the sheet sensor 36e stored in the HDD 113, the upper surface provided between the sheet sensor 36d and the sheet sensor 36e. It is determined that a transport failure has occurred in any of the transport rollers 35d and 35e, and the transport is stopped.

  When the conveyance failure is detected by the conveyance failure detection unit 102 and the conveyance is stopped, the factor determination unit 103 resumes conveyance, and based on the acceleration time calculated by the acceleration time calculation unit 101, the upper surface conveyance rollers 35d and 35e. It is determined whether the transport failure of the machine is caused by either a mechanical factor or a control factor. Specifically, the factor determination unit 103 determines that the acceleration time immediately before the resumption of the conveyance of the upper surface conveyance roller 35 d calculated by the acceleration time calculation unit 101 is shorter than the specified acceleration time of the upper surface conveyance roller 35 d stored in the HDD 113. In this case, it can be estimated that there is a high possibility that the sheet P can not be pressed and is idle. Therefore, the factor determination unit 103 determines that the conveyance failure of the upper surface conveyance roller 35d is a mechanical factor such as wear of the roller itself or a failure of the upper surface motor 58d.

  On the other hand, if the acceleration time immediately before the resumption of the conveyance of the upper surface conveyance roller 35d calculated by the acceleration time calculation unit 101 is equal to or longer than the specified acceleration time stored in the HDD 113, the factor determination unit 103 It is determined that the transport failure is not a mechanical factor but a control factor such as timing failure due to noise or false detection of a control signal. Similarly, the factor determination unit 103 also determines whether the conveyance failure is caused by either a mechanical factor or a control factor for the upper surface conveyance roller 35 e.

  The conveyance control setting unit 104 changes the setting value of conveyance control by the top conveyance roller 35 d when the factor determination unit 103 determines that the conveyance failure of the top conveyance roller 35 d is a control factor. For example, the specified detection time from when the leading edge of the sheet P conveyed on the normal route RC is detected by the sheet sensor 36d to when the leading edge of the sheet P is detected by the sheet sensor 36e is set to 100 (msec) or less It is assumed that At this time, if it is determined that the conveyance failure of the upper surface conveyance roller 35 d is a control factor, the conveyance control setting unit 104 sets, for example, the predetermined knowledge time to 105 (msec) or less so that the printing process can be continued. And reset it in the direction to ease it so as not to cause transport failure. Further, the conveyance control setting unit 104 may be reset so as to increase the number of rotations of the upper surface motor 58 d in order to increase the conveyance speed (rotational speed) of the upper surface conveyance roller 35 d.

  When the factor determination unit 103 determines that the conveyance failure of the upper surface conveyance roller 35d is a mechanical factor, the notification unit 105 transmits a message indicating that the upper surface conveyance roller 35d or the upper surface motor 58d has a mechanical defect. It is displayed on the operation panel unit 10. For example, the notification unit 105 causes the operation panel unit 10 to display a message such as "There is a possibility that a problem has occurred in the upper surface conveyance roller. Contact a service person."

  In the example shown in FIG. 3, two upper surface conveyance rollers 35d and 35e are provided between the sheet sensors 36d and 36e. However, the present invention is not limited to this. One conveyance roller is provided between the sheet sensors. It is applicable also when provided.

  In the example shown in FIG. 3, the upper surface motor 58 d for rotationally driving the upper surface conveyance roller 35 d and the upper surface motor 58 e for rotationally driving the upper surface conveyance roller 35 e have been described as an example. A plurality of conveyance rollers such as the conveyance roller 35d and the upper surface conveyance roller 35e may be shared by one motor and rotationally driven.

  Furthermore, in the example shown in FIG. 3, the sheet sensors 36d and 36e disposed in the normal path RC in the upper surface conveyance unit 6, the upper surface conveyance rollers 35d and 35e provided between the sheet sensors 36d and 36e, and the upper surface The upper surface motor 58d for rotating and driving the conveyance roller 35d and the upper surface motor 58e for rotating and driving the upper surface conveyance roller 35e have been described as an example, but the present invention is not limited to this. For the transport roller, it is determined whether the transport failure is due to either a mechanical factor or a control factor.

  Next, the operation of the printing apparatus 1 according to the embodiment of the present invention will be described with reference to the flowchart shown in FIG.

  As shown in FIG. 4, when printing based on image data is instructed from a personal computer connected via a communication network (step S101; YES), the CPU 100 determines the prescribed detection time and the prescribed acceleration stored in the HDD 113. The time is read (step S103).

  Next, the CPU 100 starts conveyance of the sheet P and executes printing (step S105).

  When sheet conveyance is started in each conveyance unit, the conveyance failure detection unit 102 calculates a detection time (step S107). Specifically, every time the sheet sensor detects the sheet P being conveyed, the leading edge of the sheet P is detected by the sheet sensor disposed on the upstream side of the conveyance path of the detected sheet sensor. The time that has elapsed since it was calculated is calculated as the detection time.

  Next, the acceleration time calculation unit 101 calculates an acceleration time (step S109). Specifically, the acceleration time calculation unit 101 calculates, as an acceleration time, a time from when rotational driving is started for each conveyance roller until it reaches a predetermined conveyance speed (rotational speed).

  Next, the conveyance failure detection unit 102 determines whether a conveyance error has occurred (step S111). Specifically, when the detection time calculated in step S107 exceeds the defined detection time read in step S103, the conveyance failure detection unit 102 is provided between the sheet sensors determined to have exceeded the defined detection time. It is determined that a transport error has occurred in the transport roller being loaded.

  If it is determined that a transport error has not occurred (step S111; NO), the processes of steps S107 to S113 are repeatedly executed until printing is completed (step S113; NO).

  On the other hand, when it is determined that a conveyance error has occurred in any of the sheet sensors (step S111; YES), the CPU 100 temporarily stops all conveyance (step S115). As a result, the printing is stopped and the sheet P stands by at the position where the conveyance is stopped on the conveyance path.

  Next, after a predetermined time has elapsed, the CPU 100 resumes the conveyance of the sheet P (step S117).

  Then, in step S111, it is determined whether or not the sheet P is detected by the sheet sensor corresponding to the location where the transport error has occurred (step S119).

  When the sheet P is detected at the sheet sensor corresponding to the position where the transport error has occurred (step S119; YES), the value of the control factor counter K1 is incremented by "1" (step S121).

  Then, the process proceeds to step S125, and when the acceleration time of the conveyance roller causing the conveyance error calculated by the conveyance failure detection unit 102 is shorter than the specified acceleration time stored in the HDD 113 (step S125; YES), the conveyance is resumed. However, it can be determined that the transport failure is likely to be a mechanical factor such as wear of the roller itself or failure of the motor.

  Therefore, the factor determination unit 103 adds "1" to the value of the mechanical factor counter K2 (step S123), and determines whether the mechanical factor counter K2 is equal to or more than a predetermined mechanical factor threshold (step S135). ).

  If it is determined that the mechanical factor counter K2 is equal to or higher than the predetermined mechanical factor threshold (step S135; YES), the factor determination unit 103 has repeatability, such as conveyance failure, wear of the roller itself, breakdown of the motor, etc. (Step S127), and the notification unit 105 causes the operation panel unit 10 to display a message notifying that there is a mechanical defect in the conveyance roller, the motor, etc. in which the conveyance failure occurred. S129).

  On the other hand, when the acceleration time of the conveyance roller causing the conveyance error calculated by the conveyance failure detection unit 102 is equal to or longer than the specified acceleration time stored in the HDD 113 (step S125; NO), it can be estimated that it is not a mechanical factor.

  Therefore, the factor determination unit 103 determines whether the control factor counter K1 is equal to or more than a predetermined control factor threshold (step S131).

  If it is determined that the control factor counter K1 is equal to or more than the predetermined control factor threshold (step S131; YES), it can be inferred that conveyance defects occur frequently although the conveyance can be resumed, so the conveyance control setting unit 104 The control setting value of the conveyance according to is changed (step S133). The conveyance control setting unit 104 sets the specified detection time to a long time or increases the number of rotations of the motor.

  Further, in the determination of step S119, when the sheet P is not detected by the sheet sensor corresponding to the location where the transport error occurs (step S119; NO), the sheet P is not actually transported even if the transport is resumed. Therefore, the process proceeds to step S127, and the factor determination unit 103 determines that the factor is a mechanical factor.

  As described above, according to the printing apparatus 1 according to the embodiment of the present invention, based on the detection result of the sheet transported from the upstream side to the downstream side on the transport path by the sheet sensor, the transport failure in the transport path Detection of the occurrence of a failure, and the conveyance failure stopped by the conveyance failure detection unit 102 for stopping the conveyance, and the position where the conveyance failure is detected by the acceleration time calculation unit 101 is resumed. And a factor determination unit (103) that determines whether the transport failure is caused by a mechanical factor or a control factor based on an acceleration time immediately before the transport roller resumes transport.

  Therefore, when a transport failure occurs, the cause of the transport failure can be determined. As a result, the user can take appropriate measures to eliminate the conveyance failure depending on the cause.

  In addition, when the acceleration time immediately before the conveyance restart of the conveyance roller at the position where the conveyance failure is detected calculated by the acceleration time calculation unit 101 is shorter than the predetermined acceleration time, the factor determination unit 103 detects the conveyance failure. It is determined that the mechanical factor is a factor, and if it is a predetermined acceleration time or more, it is determined that the transport failure is a control factor.

  Therefore, if the acceleration time is shorter than the specified acceleration time, the conveyance roller idles due to insufficient pressing force of the conveyance roller, and it is estimated that this idle rotation is a mechanical factor such as roller wear, while the acceleration time is equal to or longer than the specified acceleration time In this case, since it is determined that the control factor is not the mechanical factor such as the transport roller or the motor, it is possible to appropriately determine whether the transport failure is due to the mechanical factor or the control factor.

  Furthermore, when the factor determination unit 103 determines that the transport failure of the transport roller is a control factor, the control setting value of the sheet transport by the roller driving unit is changed.

  When the conveyance failure is a control factor, the members such as the conveyance roller and the motor are not immediately repaired or replaced. In this case, it is possible to estimate that there is no fatal problem in continuing printing, and to continue printing by changing the control setting value.

  When the factor determination unit 103 determines that the conveyance failure is a mechanical factor, the notification unit 105 notifies that effect.

  Therefore, the user can immediately contact the service person and request repair or replacement of a defective transport roller or a mechanical device such as a motor for rotationally driving the transport roller, so the cause of the transport failure is fundamentally Can be resolved.

  In the printing apparatus 1 according to the embodiment of the present invention, the control factor counter K1 or the mechanical factor counter K2 is used to determine whether the transport failure of the transport roller is caused by a mechanical factor or a control factor. However, the present invention is not limited to this, and the determination may be made without using the control factor counter K1 or the mechanical factor counter K2. In the flowchart shown in FIG. 5, the processing of steps S131 and S135 may be omitted.

  Further, in the printing apparatus 1 according to the embodiment of the present invention, the control factor threshold value and the mechanical factor threshold value are fixed values set in advance, but the sheet type of the sheet P (plain paper, matte paper, thick paper, etc. These threshold values may be changed according to the conveyance setting of the sheet P (single-sided / double-sided setting) or the like. For example, the threshold value of the sheet may be set to be larger as the sheet state is more slippery.

(Supplementary note)
The present application discloses the following invention.

(Supplementary Note 1)
Roller driving means for conveying the sheet along the conveyance path by rotationally driving a plurality of conveyance rollers provided for the conveyance path;
A plurality of sheet detection means provided for the conveyance path and detecting a sheet conveyed by the conveyance roller;
Acceleration time calculating means for calculating an acceleration time from the start of rotational driving of the transport roller to reaching a predetermined rotational speed;
Conveyance defect detection means for detecting the occurrence of conveyance failure in the conveyance path based on the detection result of the sheet conveyed from the upstream side to the downstream side on the conveyance path by the paper detection means, and stopping the conveyance; ,
The conveyance stopped by the conveyance failure detection means is resumed, and the conveyance calculated based on the acceleration time calculation means is based on the acceleration time immediately before the conveyance restart of the conveyance roller at the position where the conveyance failure is detected. Factor determination means for determining the cause of failure;
A printing apparatus comprising:

(Supplementary Note 2)
The factor determination unit
The conveyance failure is a mechanical factor when the acceleration time immediately before the conveyance restart of the conveyance roller at the position where the conveyance failure is detected calculated by the acceleration time calculation means is shorter than a predetermined acceleration time (Supplementary Note 1) The printing apparatus according to Supplementary Note 1, wherein it is determined that the conveyance failure is a control factor if the acceleration time is longer than a predetermined acceleration time.

(Supplementary Note 3)
A conveyance control unit configured to change a control setting value of the sheet conveyance by the roller driving unit when the factor judging unit judges that the conveyance failure is a control factor;
The printing apparatus according to (Appendix 2), further comprising:

(Supplementary Note 4)
When the factor determination means determines that the transport failure is a mechanical factor, a notification means for notifying that effect is provided;
The printing apparatus according to (Appendix 2) or (Appendix 3), further comprising:

DESCRIPTION OF SYMBOLS 1 printing apparatus 2 sheet feeding unit 3 vertical conveyance unit 4 conveyance printing unit 4 printing conveyance unit 5 ink jet head unit 6 upper surface conveyance unit 7 upper sheet discharge conveyance unit 8 upper discharge tray 9 reversing unit 10 operation panel unit 11 control unit 13 straight going Sheet delivery / conveyance unit 14 Straight delivery table 22 Side sheet feeding roller 24 Internal sheet feeding roller 25a to 25d Vertical conveying roller 27a to 27e Sheet sensor 28 Merged sheet feeding roller 31 Registration roller 32 Belt conveyance portion 33a to 33d Sheet sensor 34 Switching portion 35 upper surface conveying rollers 35a to 35f upper surface conveying rollers 36a to 36f sheet sensor 37 sheet discharging roller 38 sheet sensor 39 suction fan 41 switching portion 42 sheet discharging roller 43 sheet sensor 44 roller 45 reverse roller 46 switchback portion 47 refeed roller 49a ~ 49b Paper sensor 50 Suction motor 51 Side feed motor 52 Internal feed mode 5 combined sheet feed motor 54 registration motor 55 belt motor 56 linear discharge motor 57 upper discharge motor 58a to 58f upper surface motor 59 reverse motor 60 refeed motor 61, 62 solenoid 101 acceleration time calculation unit 102 conveyance failure detection unit 103 Cause determination unit 104 Transport control setting unit 105 Notification unit 114 Connection unit

Claims (4)

Roller driving means for conveying the sheet along the conveyance path by rotationally driving a plurality of conveyance rollers provided for the conveyance path;
A plurality of sheet detection means provided for the conveyance path and detecting a sheet conveyed by the conveyance roller;
Acceleration time calculating means for calculating an acceleration time from the start of rotational driving of the transport roller to reaching a predetermined rotational speed;
Conveyance defect detection means for detecting the occurrence of conveyance failure in the conveyance path based on the detection result of the sheet conveyed from the upstream side to the downstream side on the conveyance path by the paper detection means, and stopping the conveyance; ,
The conveyance stopped by the conveyance failure detection means is resumed, and the conveyance calculated based on the acceleration time calculation means is based on the acceleration time immediately before the conveyance restart of the conveyance roller at the position where the conveyance failure is detected. Factor determination means for determining the cause of failure;
A printing apparatus comprising: The factor determination unit
The conveyance failure is a mechanical factor when the acceleration time immediately before the conveyance restart of the conveyance roller at the position where the conveyance failure is detected calculated by the acceleration time calculation means is shorter than a predetermined acceleration time The printing apparatus according to claim 1, wherein the printing apparatus is determined, and the transport failure is determined to be a control factor when the acceleration time is equal to or more than a predetermined acceleration time. A conveyance control unit configured to change a control setting value of the sheet conveyance by the roller driving unit when the factor judging unit judges that the conveyance failure is a control factor;
The printing apparatus according to claim 2, further comprising: When the factor determination means determines that the transport failure is a mechanical factor, a notification means for notifying that effect is provided;
The printing apparatus according to claim 2, further comprising:

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