JP6241114B2 - Printing device - Google Patents

Description

  The present invention relates to a printing apparatus that performs printing on a sheet-like print medium.

  Conventionally, an apparatus described in Patent Literature 1 is known as a printing apparatus having a double-sided printing function. This type of printing apparatus has a reversing mechanism for reversing the printing surface of a sheet as a printing medium from the front surface to the back surface.

  FIG. 5 shows a configuration of a reversing mechanism provided in the printing apparatus described in the document. In the following description, the paper supply side (paper feed side) in the paper transport path in the printing apparatus is described as upstream of the same transport path, and the paper discharge side (paper discharge side) in the same transport path is described. It is described as downstream of the transport path.

  As shown in the figure, the reversing mechanism has two transport rollers provided in the paper transport path, that is, an intermediate roller 50, and a paper feed roller 51 disposed downstream thereof. The intermediate roller 50 and the paper feed roller 51 are rotationally driven by a common motor. The downstream side of the paper feed roller 51 in the transport path is a print area in which a carriage 53 having a print head 52 is arranged.

  Hereinafter, the rotation of the conveyance roller on the side that sends the paper downstream of the conveyance path is described as normal rotation, and the rotation of the conveyance roller on the side that sends the paper upstream of the conveyance path is described as reverse rotation. The paper feed roller 51 can be switched between forward rotation and reverse rotation according to switching of the rotation direction of the motor. On the other hand, the intermediate roller 50 is always rotated only in the forward rotation direction regardless of the rotation direction of the motor and the paper feed roller 51.

Next, the operation of the reversing mechanism during duplex printing will be described.
FIG. 6A shows the state of the reversing mechanism immediately after the paper P is fed. At this time, both the intermediate roller 50 and the paper feed roller 51 are rotated forward. As shown in the figure, the fed paper P is first transported downstream by the forward rotating intermediate roller 50 and then further transported to the downstream printing area by the forward paper transporting roller 51. Is done. Then, the surface of the paper P is printed in the printing area.

  FIG. 6B shows a state of the reversing mechanism after the surface of the paper P is printed. When printing on the surface of the paper P is completed, the paper feed roller 51 is reversed and the paper P is conveyed toward the intermediate roller 50. As described above, even when the paper feed roller 51 is reversed, the rotation of the intermediate roller 50 is maintained in the normal rotation. The paper P conveyed by the reverse paper feed roller 51 first enters the lower side of the intermediate roller 50, and after having rotated around the periphery by the forward intermediate roller 50, the paper P is fed from the upper part of the intermediate roller 50. Returned to the roller 51 side. Thereby, the printing surface of the paper P is reversed from the front surface to the back surface.

  FIG. 6C shows the state of the subsequent reversing mechanism. As shown in the figure, when the trailing end of the paper P passes through the paper feed roller 51, the rotation direction of the paper feed roller 51 is switched from reverse rotation to normal rotation. On the other hand, even after this switching, the rotation of the intermediate roller 50 is maintained in the normal direction, and the conveyance of the paper P to the downstream side by the intermediate roller 50 is continued. Then, the paper P returned from the intermediate roller 50 is further conveyed to the downstream printing area by the normal paper feeding roller 51, where the back side of the paper P is printed.

  As described above, in the conventional printing apparatus, regardless of the rotation direction of the paper feed roller 51, the rotation direction of the intermediate roller 50 is maintained, so that an individual motor is provided for each roller, or both rollers are provided. Double-sided printing can be performed without providing a mechanism for individually switching the rotation directions of the two.

  By the way, in the printing apparatus described in Patent Document 1, when the printing waiting time becomes long or the power is turned off, the carriage 53 is retracted to the home position provided outside the printing area and the carriage 53 is moved. Maintenance operations of the print head 52 such as locking or putting a cap on the print head 52 are performed. In the conventional printing apparatus, the maintenance operation of the print head 52 is also performed by a motor common to the intermediate roller 50 and the paper feed roller 51. More specifically, the maintenance operation as described above is performed by rotating the motor to the side where the paper feed roller 51 is reversed.

JP 2010-58952 A

  By the way, in the above-described conventional printing apparatus, power transmission from the motor to each transport roller is maintained even during the maintenance operation, the intermediate roller 50 is rotated forward, and the paper feed roller 51 is reversed. Normally, the maintenance operation is performed in a state where there is no paper in the transport path, and therefore the intermediate roller 50 and the paper feed roller 51 at this time are merely idle.

  However, even during such a maintenance operation, the user may manually feed paper. In such a case, the fed paper P is conveyed by the intermediate roller 50 to the paper feed roller 51 side. Depending on the timing, the front end of the fed paper P may reach the paper feed roller 51.

  FIG. 7 shows the state of the reversing mechanism at this time. As shown in the figure, even if the front end of the paper P reaches the paper feed roller 51, the paper feed roller 51 at this time is reversed, so that the front end of the paper P is not further conveyed downstream in the transport direction. It becomes like this. On the other hand, since the rear end portion of the paper P continues to be fed downstream in the transport direction by the forwardly rotating intermediate roller 50, the paper P bends at the portion between the intermediate roller 50 and the paper feed roller 51, and a paper jam occurs. There is a risk.

  It is possible to release the maintenance state of the print head 52 in conjunction with the reverse rotation of the paper feed roller 51. In such a case, an operation for the release (maintenance release operation) is in progress. Similarly, when paper is fed, there is a possibility that a paper jam will occur.

  The present invention has been made in view of such circumstances, and the problem to be solved is that of a print medium that is generated when the print medium enters the conveyance path during execution of an operation related to maintenance of the print head. An object of the present invention is to provide a printing apparatus that can suitably avoid clogging.

  A printing apparatus that solves the above-described problem is a printing apparatus that performs printing on a sheet-like print medium using a print head, and the supply side of the print medium in the print medium conveyance path in the printing apparatus is connected to the conveyance path. When the upstream side is the upstream side and the discharge side of the print medium is downstream of the transport path, the forward rotation direction in which the print medium is transported to the downstream side of the transport path, and the print medium is transported to the upstream side of the transport path. A first transport roller that is rotationally driven in both the reverse direction and an upstream of the first transport roller in the transport path, and interlocks with both the forward and reverse rotations of the first transport roller. A second transport roller that is driven to rotate in the forward direction for transporting the print medium downstream of the transport path, and one of the rotation in the forward direction and the reverse direction of the first transport roller. Before A maintenance mechanism that performs an operation for bringing the print head into a maintenance state, and an operation for releasing the maintenance state in conjunction with the other of the rotations, and a rotation in the reverse direction of the first transport roller. And a control unit that interrupts the operation when it is confirmed that the print medium is present in the transport path during the operation of the maintenance mechanism.

  In the above configuration, either the operation of the maintenance mechanism for bringing the print head into the maintenance state or the operation of the maintenance mechanism for releasing the maintenance state is performed in conjunction with the rotation of the first transport roller in the reverse direction. Is called. During execution of such an operation, the first transport roller is rotated in the reverse direction, and the second transport roller is rotated in the forward direction. When the printing medium is supplied to the printing apparatus at this time, the printing medium may be nipped by the second conveying roller that rotates in the forward direction and sent to the downstream side of the conveying path. Even if the front end of the print medium reaches the first transport roller, the first transport roller at this time is reversed, and the front end of the print medium is not sent further downstream in the transport path. On the other hand, since the rear end portion of the print medium continues to be sent to the downstream side of the conveyance path by the second conveyance roller that normally rotates, the print medium is bent at a portion between the first conveyance roller and the second conveyance roller, There is a risk that the print medium will be jammed in the transport path.

  In that respect, in the above configuration, when it is confirmed that the print medium exists in the transport path during the operation of the maintenance mechanism linked to the rotation of the first transport roller in the reverse rotation direction, the control unit performs the maintenance operation. Interrupt the operation. For this reason, the clogging of the print medium as described above is prevented in advance. Therefore, according to the above configuration, it is possible to suitably avoid the clogging of the print medium that occurs when the print medium enters the conveyance path during the execution of the operation related to the maintenance of the print head.

  In such a printing apparatus, if the control unit is configured to discharge the printing medium existing in the conveyance path from the printing apparatus after the operation of the maintenance mechanism is interrupted, the printing medium can be more reliably protected.

  In the printing apparatus as described above, the operation of the maintenance mechanism for putting the print head in the maintenance state includes, for example, an operation of locking the carriage provided with the print head at a predetermined operation position, and an operation of covering the print head with a cap. and so on.

  In addition, the operation of the maintenance mechanism related to the maintenance of the print head in the printing apparatus as described above is performed, for example, before the start of printing, when the gap between the support base supporting the print medium and the print head is adjusted, or when the printing apparatus is turned off. It may be performed before or after a prescribed preparatory operation such as reducing the gap.

  On the other hand, it is desirable to confirm the presence of the print medium in the transport path in the printing apparatus in a section between the first transport roller and the second transport roller in the transport path. In this way, it is possible to more accurately avoid the clogging of the print medium caused by the supply of the print medium during the print head maintenance operation or the maintenance release operation.

The schematic diagram which shows the side surface cross-section of one Embodiment of a printing apparatus. FIG. 2 is a schematic diagram illustrating a power transmission system and a control system in the printing apparatus according to the embodiment. FIG. 3 is a schematic diagram illustrating a configuration of a maintenance mechanism provided in the printing apparatus according to the embodiment. 6 is a flowchart showing a processing procedure of a maintenance operation routine executed by the printing apparatus of the embodiment. FIG. 6 is a schematic diagram illustrating a configuration of a reversing mechanism provided in a conventional printing apparatus. (A)-(c) The figure which shows the operation | movement aspect of the inversion mechanism at the time of double-sided printing in the conventional printing apparatus. FIG. 10 is a diagram illustrating a state of a reversing mechanism when paper feeding is performed during a maintenance operation in a conventional printing apparatus.

Hereinafter, an embodiment of a printing apparatus will be described in detail with reference to FIGS. Note that the printing apparatus of the present embodiment is configured as an ink jet printing apparatus.
FIG. 1 shows a side sectional structure of the internal structure of the printing apparatus according to the present embodiment. The printing apparatus includes a square box-shaped main body frame 10. In the following, the right side in the figure is the front of the printing apparatus, and the left side in the figure is the rear of the printing apparatus.

An operation panel 11 serving as a user interface is provided on the front side surface of the main body frame 10. The operation panel 11 is provided with operation switches and a liquid crystal panel. In addition, an extendable paper discharge tray 25 on which printed paper P is placed is provided at the front of the main body frame 10. Further, an openable manual paper feed port cover 12 is provided at the upper rear of the main body frame 10. By opening the manual paper feed port cover 12 , a manual paper feed port 22 which is an example of a manual feed port for manually inserting the paper P is opened.

  On the other hand, a sheet tray 13 that can accommodate a large number of sheets P in a stacked state is detachably provided below the main body frame 10. A feed mechanism 34 that feeds the paper P in the paper tray 13 is provided above the paper tray 13 in the main body frame 10. The feed mechanism 34 includes a swing arm 14 that is pivotally supported by the main body frame 10 and a pickup roller 15 provided at the tip of the swing arm 14. The pickup roller 15 feeds the uppermost one from the stack of sheets P accommodated in the sheet tray 13 in accordance with the rotation. Note that the rear wall surface of the paper tray 13 is a separation slope 16 that is inclined backward as it goes upward.

  In this printing apparatus, the transport path C1 of the paper P fed from the paper tray 13 is directed from the stack of the paper P in the paper tray 13 toward the separation slope 16, and is directed upward at the separation slope 16 and then forward. It is formed so as to be folded back toward the paper discharge tray 25. Further, the transport path C2 of the paper P fed from the manual paper feed port 22 is common to the transport path C1 after joining from the manual paper feed port 22 to the portion immediately after the return of the transport path C1. In the following, the paper feed side in the transport paths C1 and C2 is referred to as the upstream of the transport paths C1 and C2, and the paper discharge side is referred to as the downstream of the transport paths C1 and C2.

  An intermediate roller 17 as an example of a second transport roller is provided downstream of the separation slope 16 in the transport path C1. A separation roller 18 that rotates following the rotation of the intermediate roller 17 is provided adjacent to the intermediate roller 17. The outer peripheral surface of the separation roller 18 is formed of an elastic material and is pressed against the intermediate roller 17 with a specified force. As a result, the paper P passing between the intermediate roller 17 and the separation roller 18 is given an appropriate rotational resistance, thereby preventing the double feeding of the paper P.

  Further, an intermediate assist roller 19 that rotates following the rotation of the intermediate roller 17 is provided in a state of being pressed against the intermediate roller 17 downstream of the separation roller 18 in the transport path C1.

Further, a paper feed roller 20 as an example of a first transport roller is provided downstream of the intermediate assist roller 19 in the transport paths C1 and C2. A paper feed assist roller 21 that rotates following the rotation of the paper feed roller 20 is pressed against the paper feed roller 20. In the vicinity of the paper feed roller 20 on the upstream side of the transport paths C1 and C2 , a paper detection sensor (hereinafter referred to as a PE sensor 40), which is an example of a print medium detection unit that detects the presence or absence of the paper P at that position. To be described). As the PE sensor 40, for example, an optical sensor is used.

  Further, a paper discharge roller 23 is provided downstream of the paper feed roller 20 in the transport paths C1 and C2. A paper discharge assist roller 24 that rotates following the rotation of the paper discharge roller 23 is pressed against the paper discharge roller 23.

  On the other hand, a guide shaft 26 extending in the scanning direction (in the direction perpendicular to the paper surface in the figure) is installed inside the main body frame 10. A carriage 27 is provided on the guide shaft 26 so as to be movable in the scanning direction along the guide shaft 26. An ink jet print head 28 is provided below the carriage 27. A plurality of rows of nozzles that eject ink are opened on the lower surface of the print head 28. Note that the print head 28 is positioned above the section between the paper feed roller 20 and the paper discharge roller 23 in the transport paths C1 and C2 during printing.

  Further, a support base 29 that supports the paper P is provided at a position facing the print head 28 inside the main body frame 10. The carriage 27 is provided so as to be movable up and down in the drawing, and the distance between the print head 28 and the support base 29 (hereinafter referred to as gap adjustment) can be adjusted according to the elevation. Yes.

(Power transmission system)
FIG. 2 shows the configuration of the power transmission system of the printing apparatus of this embodiment. In the figure, the configuration of the control system of the printing apparatus of this embodiment is also shown.

  As shown in the figure, this printing apparatus includes two motors, that is, a carriage drive motor (hereinafter referred to as CR motor 30) and a transport motor (hereinafter referred to as PF motor 31) as power sources. Yes. The power of the CR motor 30 is transmitted to the carriage 27 and used to move the carriage 27 in the scanning direction.

  On the other hand, the power of the PF motor 31 is transmitted to the paper feed roller 20 and the paper discharge roller 23 to be used for rotation thereof. The rotation directions of the paper feed roller 20 and the paper discharge roller 23 are switched according to the rotation direction of the PF motor 31. Hereinafter, the rotation of the paper feed roller 20 and the paper discharge roller 23 in the direction in which the paper P is transported downstream of the transport paths C1 and C2, and the rotation of the PF motor 31 at that time are referred to as normal rotation. The rotation of the paper feed roller 20 and the paper discharge roller 23 in the direction of transporting the paper P upstream of the transport paths C1 and C2, and the rotation of the PF motor 31 at that time are referred to as reverse rotation.

  The power of the PF motor 31 is also transmitted to the intermediate roller 17 through the rotation direction maintaining mechanism 32. The rotation direction maintaining mechanism 32 is configured to maintain the rotation direction of the intermediate roller 17 constant regardless of the rotation direction of the PF motor 31. Specifically, the rotation direction maintaining mechanism 32 maintains the rotation direction of the intermediate roller 17 in the normal rotation direction in which the paper P is conveyed downstream of the conveyance paths C1 and C2, regardless of whether the PF motor 31 is normal or reverse. The That is, in this printing apparatus, the intermediate roller 17 is rotationally driven in the forward rotation direction in conjunction with the forward rotation direction and the reverse rotation direction of the paper feed roller 20 and the paper discharge roller 23.

  Further, the power of the PF motor 31 is also transmitted to the power transmission switching mechanism 33. The power transmission switching mechanism 33 selectively switches a mechanism for transmitting the power of the PF motor 31 from a plurality of mechanisms provided in the printing apparatus. The power transmission switching mechanism 33 that is a target of power transmission switching includes the above-described feed mechanism 34, a maintenance mechanism 35 that performs a maintenance operation for the print head 28, a suction pump 36 for cleaning the print head 28, and the gap. There is a PG adjustment mechanism 37 that performs adjustment.

(Control system)
On the other hand, the printing apparatus includes a controller 38 as an example of a control unit that performs various controls of the printing apparatus. The controller 38 is connected to the operation panel 11, checks the operation status of the operation switch provided on the operation panel 11, and performs display control of the liquid crystal panel provided on the operation panel 11. The controller 38 is communicably connected to an external host device 39 such as a personal computer. Further, the controller 38 is connected to various sensors provided in the printing apparatus, including the above-described PE sensor 40. The controller 38 controls the CR motor 30, the PF motor 31, the print head 28, and the like to perform various operations of the printing apparatus.

(Maintenance mechanism)
FIG. 3 shows the configuration of the maintenance mechanism 35. The maintenance mechanism 35 is provided immediately below a specified position (hereinafter referred to as a home position) set outside the print area in the movement range of the carriage 27.

  As shown in the figure, the maintenance mechanism 35 includes an elevating mechanism 41. The lifting mechanism 41 is provided with a lock member 42 and a slider 43 so as to be vertically movable. On the upper surface of the slider 43, a cap 44 that covers the print head 28 is installed via a spring 45. A lock groove 48 with which the lock member 42 can be engaged is formed on the lower surface of the carriage 27, and the lock member 42 is located at a position facing the lock groove 48 when the carriage 27 is located at the home position. Is provided. The cap 44 is provided at a position facing the print head 28 when the carriage 27 is located at the home position. Incidentally, the suction pump 36 is connected to the cap 44 through a pipe 49.

  On the other hand, in the elevating mechanism 41, two cams 46 and 47 that are operated by the power transmitted from the PF motor 31 via the power transmission switching mechanism 33 are incorporated. The cam 46 is in contact with the lower end of the lock member 42, and the cam 47 is in contact with the lower end of the slider 43. The lock member 42 and the slider 43 are moved up and down in accordance with the driving of the cams 46 and 47. Incidentally, in this printing apparatus, the locking member 42 and the slider 43 are lowered according to the forward rotation of the PF motor 31, and the locking member 42 and the slider 43 are raised according to the reverse rotation of the PF motor 31. A mechanism 41 is configured.

Next, the operation of the maintenance mechanism 35 configured as described above will be described.
In the printing apparatus according to the present embodiment, when the printing waiting time becomes long or when the power is turned off, a maintenance operation for putting the print head 28 in the maintenance state is performed. In this maintenance operation, the carriage 27 is first moved to the home position. Further, the power transmission switching mechanism 33 is driven so that the power of the PF motor 31 can be transmitted to the maintenance mechanism 35, more specifically to the lifting mechanism 41. Subsequently, the PF motor 31 is reversed to raise the lock member 42 and the slider 43. As a result, the lock member 42 is engaged with the lock groove 48 of the carriage 27 to lock the carriage 27, so-called carriage lock is performed. At the same time, so-called capping of the print head 28 in which the cap 44 is put on the print head 28 of the carriage 27 is performed. In this printing apparatus, the state where the carriage lock and capping are performed is the maintenance state of the print head 28.

  On the other hand, when the PF motor 31 is rotated forward after connecting the power transmission path from the PF motor 31 to the maintenance mechanism 35 with the carriage locked and capped, the lock member 42 and the slider 43 are lowered. As a result, the lock member 42 is removed from the lock groove 48 of the carriage 27 and the carriage lock is released. At the same time, the cap 44 is removed from the print head 28 of the carriage 27, and the capping of the print head 28 is released. As described above, in this printing apparatus, the operation of the maintenance mechanism 35 for releasing the maintenance state of the print head 28, that is, the maintenance release operation is performed in conjunction with the forward rotation of the paper feed roller 20.

  In the printing apparatus according to the present embodiment, as described above, the maintenance operation of the maintenance mechanism 35 is performed by the reverse rotation of the PF motor 31. In response to the reverse rotation of the PF motor 31 at this time, the paper feed roller 20 and the paper discharge roller 23 are reversely rotated, and the intermediate roller 17 is normally rotated. That is, in this printing apparatus, a maintenance operation for putting the print head 28 in the maintenance state is performed as “operation of the maintenance mechanism interlocked with the rotation of the first transport roller in the reverse direction”. Incidentally, if the paper P does not exist in the transport paths C1 and C2 at this time, the intermediate roller 17, the paper feed roller 20, and the paper discharge roller 23 are merely idled.

(Printing operation)
Next, details of the printing operation in the printing apparatus of the present embodiment will be described.
When the controller 38 receives the print job data from the host device 39, the controller 38 determines the print condition from the print condition information included in the header of the print job data. For example, it is determined whether to perform manual paper feed or tray paper feed from the paper feed method information included in the printing condition information. Also, the size of the gap between the print head 28 and the support base 29 at the time of printing is determined from information such as the paper type and print quality included in the print condition information.

  Subsequently, the controller 38 releases the maintenance state of the print head 28, that is, the carriage lock and capping of the print head 28. Specifically, the controller 38 operates the power transmission switching mechanism 33 so that the power transmission path from the PF motor 31 to the maintenance mechanism 35 is connected. Then, the controller 38 reverses the PF motor 31 to cause the maintenance mechanism 35 to perform the maintenance release operation.

Next, the controller 38 drives the PG adjustment mechanism 37 to adjust the gap so that the determined gap is obtained.
Here, when tray feeding is performed, the controller 38 operates the power transmission switching mechanism 33 so that the power transmission path from the PF motor 31 to the feed mechanism 34 is connected after the gap adjustment is completed. Then, the controller 38 causes the paper P to be sent out from the stack in the paper tray 13 by causing the PF motor 31 to rotate forward and rotating the pickup roller 15. The fed paper P is fed by the intermediate roller 17 and the paper feed roller 20 through the transport path C1 until the front end reaches the print start position.

  On the other hand, when performing manual sheet feeding, the controller 38 waits until the user operates a sheet feeding start button provided on the operation panel 11 after the gap adjustment is completed. When the paper feed start button is operated, the controller 38 rotates the PF motor 31 in the forward direction and feeds the paper P by the intermediate roller 17 and the paper feed roller 20 until the front end reaches the print start position. To do. Note that the controller 38 operates the power transmission switching mechanism 33 so that the power transmission path from the PF motor 31 to the maintenance mechanism 35 is connected if there is no operation of the paper feed start button after a certain period of time. Then, by rotating the PF motor 31 in the reverse direction, the maintenance mechanism 35 performs the maintenance operation, and the print head 28 is put into the maintenance state.

  When the front edge of the paper P reaches the print start position, the controller 38 starts printing. In the case of single-sided printing, when printing is completed, the controller 38 discharges the printed paper P onto the paper discharge tray 25 and retracts the carriage 27 to the home position, and then ends the current print job. .

  On the other hand, in the case of duplex printing, after the front surface printing of the paper P is completed, the controller 38 causes the printing surface of the paper P to be reversed. The reversing operation is performed by reversing the PF motor 31. When the PF motor 31 is reversed, the sheet P on which the surface is printed is fed to the rear of the printing apparatus by the paper feed roller 20 that is reversed. The fed paper P first enters the lower side of the intermediate roller 17, travels around the periphery by the forwardly rotating intermediate roller 17, and then returns to the paper feed roller 20 side from the upper part of the intermediate roller 17. Thereby, the printing surface of the paper P is reversed from the front surface to the back surface. Then, the controller 38 reverses the rotation direction of the PF motor 31 after the entire sheet P has passed through the sheet feed roller 20, feeds the sheet P until the front end reaches the print start position, and then prints on the back side. To start. When the printing is completed, the controller 38 discharges the printed paper P to the paper discharge tray 25 and retracts the carriage 27 to the home position, and then ends the current print job.

  The controller 38 causes the maintenance mechanism 35 to perform a maintenance operation to place the print head 28 in the maintenance state when the next print job data is not received even after a predetermined time has elapsed after the print job is completed. .

  Further, the controller 38 operates the PG adjustment mechanism 37 so that the gap between the print head 28 and the support base 29 is reduced when the power of the printing apparatus is requested to be turned off by operating the operation panel 11, and maintenance is performed. A maintenance operation is performed on the mechanism 35 to place the print head 28 in a maintenance state, and then the power is turned off.

  As described above, in the printing apparatus according to the present embodiment, the maintenance operation of the maintenance mechanism 35 is performed when the time for waiting for printing and waiting for manual feeding becomes long or when the power is turned off. Note that when the waiting time for manual sheet feeding is prolonged, the gap adjustment by the PG adjustment mechanism 37 is performed as a preparation operation before the maintenance operation of the maintenance mechanism 35. When the power is turned off, the gap reduction by the PG adjustment mechanism 37 is performed as a preparation operation before the maintenance operation of the maintenance mechanism 35.

  In the printing apparatus according to the present embodiment, manual feeding from the manual sheet feeding port 22 may occur by the user during the maintenance operation of the maintenance mechanism 35. As described above, the maintenance operation of the maintenance mechanism 35 is performed by the reverse rotation of the PF motor 31, and the intermediate roller 17 is normally rotated during the execution. Therefore, when manual paper feeding is performed during the execution of the maintenance operation, the paper P is transported downstream of the transport path C2 by the forwardly rotating intermediate roller 17. Depending on the feeding timing, the front edge of the paper P may reach the paper feed roller 20 during the maintenance operation. At this time, the paper feed roller 20 is reversed. Therefore, if the front end of the paper P is nipped between the paper feed roller 20 and the paper feed assist roller 21 at this time, the front end portion of the paper P is sent to the upstream side of the transport path C2 by the paper feed roller 20. The rear end portion of the paper P is sent to the downstream side of the transport path C2 by the intermediate roller 17. In such a case, the central portion of the paper P may be bent and a paper jam may occur.

  Therefore, in the printing apparatus according to the present embodiment, the controller 38 interrupts the maintenance operation when it is confirmed that the paper P exists in the transport path C2 during the maintenance operation of the maintenance mechanism 35. ing. The controller 38 also discharges the paper P from the printing apparatus after the maintenance operation is interrupted. Incidentally, the presence or absence of the sheet P in the transport path C2 at this time is confirmed by the PE sensor 40 provided in the section between the intermediate roller 17 and the paper feed roller 20 in the transport path C2.

  FIG. 4 shows a flowchart of a maintenance operation routine showing the processing procedure during the maintenance operation in the printing apparatus of this embodiment. The processing of this routine is executed by the controller 38 when a maintenance operation is requested, for example, when the printing waiting time is prolonged, when the manual paper feeding waiting time is prolonged, or after the gap is reduced when the power is turned off.

When this routine is started, first, in step S100, the reverse rotation of the PF motor 31 and the maintenance operation of the maintenance mechanism 35 are started.
When the maintenance operation of the maintenance mechanism 35 is started, monitoring of the paper P by the PE sensor 40 is started in step S110. Thereafter, until the maintenance operation of the maintenance mechanism 35 is completed (S160: YES), if the state in which the paper P is not detected by the PE sensor 40 (S120: NO) is maintained, the process of this routine is terminated. On the other hand, if the paper P is detected by the PE sensor 40 before the maintenance operation is completed (S160: NO), the process proceeds to step S130.

  When the process proceeds to step S130, in step S130, the PF motor 31 is stopped and the maintenance operation is interrupted. In step S140, the paper P detected by the PE sensor 40 is discharged. When the discharge is completed, in step S150, the reverse rotation of the PF motor 31, that is, the maintenance operation is resumed. Then, after the reverse rotation of the PF motor 31 is continued until the resumed maintenance operation is completed, the processing of this routine is terminated.

Next, the operation of the printing apparatus according to this embodiment will be described.
In the printing apparatus of the present embodiment, the maintenance operation of the maintenance mechanism 35 for bringing the print head 28 into the maintenance state (the state in which the carriage lock and capping are performed) is performed by the reverse rotation of the PF motor 31, and the PF at this time In conjunction with the reverse rotation of the motor 31, the paper feed roller 20 is rotated in the reverse direction and the intermediate roller 17 is rotated in the forward direction. Therefore, when manual feeding is performed during the maintenance operation of the maintenance mechanism 35 and the sheet P is conveyed by the forwardly rotating intermediate roller 17 until the front end reaches the sheet feeding roller 20, the sheet P between them is There is a possibility that the paper P bends at the portion and causes a paper jam.

  In that regard, in the control device of this embodiment, when the presence of the sheet P in the transport path C2 is confirmed by the PE sensor 40 during the maintenance operation, the maintenance operation of the maintenance mechanism 35 is interrupted by the controller 38. Then, after the paper P existing on the transport path C2 is discharged, the interrupted maintenance operation is resumed. Therefore, a paper jam caused by the supply of the paper P during the maintenance operation as described above is preferably avoided.

According to the printing apparatus of the present embodiment described above, the following effects can be obtained.
(1) Since the intermediate roller 17 is always forwardly rotated with respect to both the forward rotation and the reverse rotation of the paper feed roller 20, the printing surface of the paper P can be reversed, and thus duplex printing can be easily performed. It can be realized by configuration.

  (2) When the controller 38 confirms that the sheet P is present in the transport path C2 during the maintenance operation of the maintenance mechanism 35 performed in conjunction with the reverse rotation of the paper feed roller 20, the maintenance operation is interrupted. Therefore, it is possible to suitably avoid a paper jam that occurs due to paper feeding during the maintenance operation.

  (3) Since the controller 38 automatically discharges the paper P existing in the transport path C2 from the printing apparatus after the maintenance operation is interrupted, the paper P can be prevented from being bent or torn.

(4) Even if the paper P is erroneously inserted during the execution of the maintenance operation, an error does not occur each time, so that usability is improved.
(5) The presence of the paper P in the transport path C2 during the maintenance operation is confirmed in the section between the intermediate roller 17 and the paper feed roller 20 in the transport path C2. Here, if the presence of the paper P is confirmed at a position closer to the manual paper feed port 22, the maintenance operation can be interrupted at an earlier time after manual paper feed. However, even if paper is fed during the maintenance operation, if the maintenance operation is completed before the paper P is nipped by the paper feed roller 20, no paper jam occurs. For this reason, if the maintenance operation is interrupted at an early stage, the frequency of unnecessary interruption increases. On the other hand, in this embodiment, since the paper P is checked at a position close to the paper feed roller 20, the frequency of maintenance operations being unnecessarily interrupted can be reduced, and paper jams can be avoided more appropriately. .

  (6) Since the presence of the sheet P in the transport path C2 during the maintenance operation is confirmed using the PE sensor 40 installed in the printing apparatus, it is necessary to newly add a sensor for the confirmation. There is no.

In addition, the said embodiment can also be changed and implemented as follows.
In the above embodiment, the maintenance operation of the maintenance mechanism 35 is interrupted and the interrupted maintenance operation is resumed after the paper P is discharged. However, if there is a concern that manual paper feeding will be performed again after the resume. The monitoring of the paper P may be continued even after the maintenance operation is resumed, and when the paper P is confirmed, the maintenance operation may be interrupted again.

  In the above embodiment, the maintenance operation is interrupted, and after the paper P is discharged, the interrupted maintenance operation is automatically restarted. However, the user operation may be requested at the time of the restart.

In the above embodiment, the paper P is automatically discharged after the maintenance operation is interrupted. However, when the paper P is discharged at this time, a user operation may be requested.
In the above embodiment, the PE sensor 40 provided in the vicinity of the upstream side of the paper feed roller 20 is used to monitor the paper P during the maintenance operation. However, for example, in the vicinity of the manual paper feed port 22 The monitoring may be performed at another position.

  In the above embodiment, the maintenance operation of the maintenance mechanism 35 is performed in conjunction with the reverse rotation of the paper feed roller 20, but the maintenance release operation of the maintenance mechanism 35 is performed in conjunction with the reverse rotation of the paper feed roller 20. May be performed. In such a case, there is a possibility that a paper jam may occur due to paper feeding during the maintenance release operation of the maintenance mechanism 35. Even in such a case, if the controller 38 is configured to interrupt the maintenance canceling operation when it is confirmed that the sheet P is present in the transport path C2 during the execution of the maintenance canceling operation, a paper jam may occur. Occurrence can be suitably avoided.

The number and position of the transport rollers (the intermediate roller 17, the paper feed roller 20, and the paper discharge roller 23) that transport the paper P may be changed as appropriate.
In the printing apparatus according to the above-described embodiment, the sheet feeding can be performed by the two methods of manual feeding and tray. However, the type and number of selectable sheet feeding methods may be changed.

In the printing apparatus according to the above-described embodiment, printing is performed using the inkjet method, but another printing method such as a dot impact method may be employed.
The printing apparatus of the above embodiment is configured as a serial type printing apparatus that performs printing while scanning the print head in the width direction of the paper P. You may comprise as an apparatus.

  In the above embodiment, a printing apparatus that performs printing on paper is configured. However, if a sheet-like printing medium is used, printing is performed so that printing is performed on another printing medium such as a cloth, a resin sheet, or a metal sheet. An apparatus can also be constructed.

  C1... Transport path (when feeding tray), C2... Transport path (when manually feeding), P... Paper, 10... Main body frame, 11 ... operation panel, 12 ... manual feed slot cover, 13. DESCRIPTION OF SYMBOLS ... Swing arm, 15 ... Pick-up roller, 16 ... Separation slope, 17 ... Intermediate roller (2nd conveyance roller), 18 ... Separation roller, 19 ... Intermediate assist roller, 20 ... Paper feed roller (1st conveyance roller), 21 ... Paper feed assist roller, 22 ... Manual feed port, 23 ... Paper discharge roller, 24 ... Paper discharge assist roller, 25 ... Paper discharge tray, 26 ... Guide shaft, 27 ... Carriage, 28 ... Print head, 29 ... Support base 30 ... CR motor, 31 ... PF motor, 32 ... rotation direction maintaining mechanism, 33 ... power transmission switching mechanism, 34 ... feed mechanism, 35 ... maintenance mechanism, 36 ... suction point 37 ... PG adjusting mechanism 38 ... Controller (control unit) 39 ... Host device 40 ... PE sensor 41 ... Elevating mechanism 42 ... Lock member 43 ... Slider 44 ... Cap 45 ... Spring 46 ... Cam, 47 ... cam, 48 ... lock groove, 49 ... pipe.

Claims (9)

A printing apparatus that performs printing on a sheet-like print medium by a print head,
When the supply side of the print medium in the transport path of the print medium in the printing apparatus is the upstream of the transport path, and the discharge side of the print medium is the downstream of the transport path,
A first transport roller that is rotationally driven in both a forward direction for transporting the print medium to the downstream side of the transport path and a reverse direction for transporting the print medium to the upstream side of the transport path;
Provided upstream of the first transport roller in the transport path, and transports the print medium downstream of the transport path in conjunction with the rotation in the forward and reverse directions of the first transport roller. A second transport roller that is rotationally driven in the forward direction;
A manual feed port for manually inserting the print medium;
A print medium detection unit for detecting the print medium conveyed in a section between the first conveyance roller and the second conveyance roller in the conveyance path;
In conjunction with the reverse rotation direction of the rotating of the first conveying roller, the operation performs to the print head and the maintenance state, conjunction with the maintenance state the rotation of the forward rotation direction of the first conveying roller A maintenance mechanism that performs actions to release
Wherein during execution of the operation of the maintenance mechanism interlocked with the rotation of the reverse rotation direction of the first conveying roller, upon detecting the print medium in the print medium detector includes a control unit to interrupt said operating,
Equipped with a,
The printing apparatus , wherein the print medium supplied from the manual supply port is transported to the downstream side of the transport path by the second transport roller . The controller, after the operation of the maintenance mechanism is interrupted, causes the printing medium present in the transport path to be discharged from the printing apparatus;
The printing apparatus according to claim 1. As an operation for bringing the print head into a maintenance state, an operation of locking a carriage provided with the print head at a specified operation position is performed.
The printing apparatus according to claim 1 or 2. As an operation for putting the print head into a maintenance state, an operation of covering the print head with a cap is performed.
The printing apparatus according to claim 1. The operation of the maintenance mechanism is performed before or after the prescribed preparation operation.
The printing apparatus of any one of Claims 1-4. As the preparatory operation, before starting printing, a gap adjustment between a support base that supports the print medium and the print head is performed.
The printing apparatus according to claim 5. As the preparatory operation, when the power of the printing apparatus is turned off, the gap between the support base that supports the print medium and the print head is reduced.
The printing apparatus according to claim 5. The printing medium detecting unit is located Oite, closer to the first transport roller than the middle of the section in a section between the first transport roller and the second transport roller in the transport path,
The printing apparatus of any one of Claims 1-7.   When the control unit detects the print medium by the print medium detection unit during execution of the operation of the maintenance mechanism in conjunction with the rotation of the first transport roller in the reverse rotation direction, the control unit interrupts the operation, Discharging the print medium detected by the print medium detection unit from the transport path;
  The printing apparatus of any one of Claims 1-8.