Patent Publication Number: US-11396194-B2

Title: Printer configured to rotate discharge roller when determining that second print control subsequent to first print control can be performed

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application No. 2019-046678 filed Mar. 14, 2019. The entire content of the priority application is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a printer. 
     BACKGROUND 
     Japanese Patent Application Publication No. 2017-43480 discloses a printer that performs printing on a medium. Once an image is printed on a medium, the medium is conveyed to a portion between a pair of discharge rollers, and is cut using a cutter in a state where the medium is nipped at the portion between the pair of discharge rollers. A sensor is configured to detect presence or absence of the medium cut by the cutter (hereinafter referred to as “segmented medium”). When the detection result by the sensor shows that the segmented medium has been removed from the portion between the discharge rollers, subsequent printing operation is enabled. The subsequent printing operation is performed upon receipt of new print instruction. 
     SUMMARY 
     In the above configuration, the sensor may erroneously detect that the segmented medium has been removed from the discharge rollers even though the segmented medium is still nipped by the discharge rollers. In this case, the subsequent printing operation becomes enabled in a state where the segmented medium remains nipped at the portion between the pair of discharge rollers. As a result, the nipped segmented medium may interfere with a medium on which the subsequent printing operation has been performed, leading to jam of the mediums in the printer. 
     In view of the foregoing, it is an object of the present disclosure provide a printer in which jam of a recording medium can be restrained. 
     In order to attain the above and other objects, according to one aspect, the disclosure provides a printer including: a printing head; a conveyor; a cutter; a discharge roller; a counter roller; a driver; and a controller. The printing head is configured to perform printing on a medium. The conveyor is configured to convey the medium in a conveying direction. The cutter is positioned downstream of the printing head and the conveyor in the conveying direction. The cutter is configured to cut the medium to provide a segmented medium. The discharge roller is positioned downstream of the cutter in the conveying direction. The counter roller is positioned to face the discharge roller and configured to nip the medium in cooperation with the discharge roller. The driver is configured to drivingly rotate the discharge roller in a discharging direction. Rotation of the discharge roller in the discharging direction causes the segmented medium to be conveyed downstream in the conveying direction. The controller is configured to perform: (a) controlling, when a first print instruction has been acquired, the printing head and the conveyor to perform a first print control on the medium, the first print control being first performed based on the acquired first print instruction to perform printing on the medium; (b) driving, when performing the (a) controlling, the driver to stop rotation of the discharge roller in a state where the medium is nipped at a portion between the discharge roller and the counter roller; and (c) driving, when a second print control is allowed to be performed, the driver to drivingly rotate the discharge roller in the discharging direction, the second print control being performed subsequent to the first print control based on a second print instruction acquired subsequent to the first print instruction to perform printing on the medium. 
     According to another aspect, the disclosure provides a printer including: a printing head; a platen roller; a cutter; a discharge roller; a counter roller; a sensor; and a controller. The printing head is configured to perform printing on a medium. The platen roller is configured to nip the medium in cooperation with the printing head. The cutter is positioned downstream of the printing head and the platen roller in a conveying direction in which the medium is conveyed. The cutter is configured to cut the medium to provide a segmented medium. The discharge roller is positioned downstream of the cutter in the conveying direction and is movable between a release position and a nipping position. The counter roller is positioned to face the discharge roller. The counter roller is configured to nip the medium in cooperation with the discharge roller at the nipping position. The counter roller is spaced away from the discharge roller at the release position to allow the medium to pass through a portion between the discharge roller and the counter roller. The sensor is positioned downstream of the discharge roller and the counter roller in the conveying direction. The sensor is configured to detect whether the segmented medium remains at the portion between the discharge roller and the counter roller. The controller configured to perform: (a) controlling, when a first print instruction has been acquired, the discharge roller to be moved to the release position; (b) controlling the printing head and the platen roller to perform printing on the medium based on the acquired first print instruction; (c) controlling, after completing the (b) controlling, the discharge roller to be moved to the nipping position; (d) controlling the cutter to provide the segmented medium; (e) preventing, when it is determined that the sensor detects that the segmented medium remains at the portion between the discharge roller and the counter roller, a second print instruction from being received, the second print instruction being acquired subsequent to the first print instruction to perform printing on the medium; (f) controlling, when it is determined that the sensor detects that the segmented medium has been removed from the portion between the discharge roller and the counter roller, the discharge roller to be rotated in a discharging direction; and (g) permitting, alter performing the (f) controlling, the second print instruction to be received. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The particular features and advantages of the disclosure will become apparent from the following description taken in connection with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a printer according to a first embodiment of the present disclosure; 
         FIG. 2  is a cross-sectional view taken along a line II-II in  FIG. 1  in which a housing of the printer according to the first embodiment is partially removed; 
         FIG. 3  is an enlarged view of a region illustrated in  FIG. 2 , and particularly illustrating a state where a discharge roller in the printer according to the first embodiment is at its nipping position; 
         FIG. 4  is an enlarged view of the region illustrated in  FIG. 2 , and particularly illustrating a state where the discharge roller in the printer according to the first embodiment is at its release position; 
         FIG. 5  is a block diagram illustrating an electrical configuration in the printer according to the first embodiment; 
         FIG. 6  is a flowchart illustrating a first main routine executed by a CPU in the printer according to the first embodiment; 
         FIG. 7A  is a schematic view for description of operation performed in the printer according to the first embodiment, and particularly illustrating a state where a print control is performed to a medium by a thermal head and a conveying roller in the printer; 
         FIG. 7B  is a schematic view for description of the operation performed in the printer according to the first embodiment, and particularly illustrating a state where the medium is nipped by the discharge roller at the nipping position and a counter roller in the printer; 
         FIG. 7C  is a schematic view for description of the operation performed in the printer according to the first embodiment, and particularly illustrating a state where the medium, is cut by a cutting blade in the printer and a segmented medium is provided; 
         FIG. 7D  is a schematic view for description of the operation performed in the printer according to the first embodiment, and particularly illustrating a state where the segmented medium nipped between the discharge roller and the counter roller is discharged downward by rotation of the discharge roller; 
         FIG. 8  is a flowchart illustrating a second main routine executed by a CPU in a printer according to a second embodiment; and 
         FIG. 9  is a flowchart illustrating a third main routine executed by a CPU in a printer according to a third embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, a printer  1  according to a first embodiment of the present disclosure will be described with reference to  FIGS. 1 through 4 . Note that configuration of the printer  1  illustrated in the drawings is merely an example and is not intended to limit the present disclosure. 
     In the following description, directions with regard to the printer  1  will be described based on a posture of the printer  1  illustrated in  FIG. 1 . Specifically, a diagonally lower leftward direction, a diagonally upper rightward direction, a diagonally lower rightward direction, a diagonally upper leftward direction, an upward direction, and a downward direction in  FIG. 1  are respectively defined as a leftward direction, a rightward direction, a frontward direction, a rearward direction, an upward direction and a downward direction of the printer  1 , respectively. 
     The printer  1  can be connected to an external terminal device (not illustrated) such as a personal computer and a smartphone via a network and a cable (not illustrated). The printer  1  is configured to acquire print data from the external terminal device, for example, and to print an image on an image recording medium (hereinafter simply referred to as “medium”)  5  on a basis of the acquired print data. 
     As illustrated in  FIG. 1 , the printer  1  includes a housing  2  and a cover  3 . The cover  3  is pivotally movably supported by the housing  2  to open and close an upper open end of the housing  2 . An input portion  4  is provided at a left-upper corner portion of a front surface of the housing  2 . A user of the printer  1  can input various information into the printer  1  by operating the input portion  4 . A display portion  9  is provided at a position below the input portion  4 . The display portion  9  is configured to display various information thereon. 
     A discharge opening  11  is formed in the front surface of the housing  2  at a position rightward of the input portion  4 . The discharge opening  11  is open and extends in an upward/downward direction. The discharge opening  11  is configured to discharge a segmented medium  51  (described later) to an outside of the housing  2 . A cassette receiving portion  6  is provided at an upper portion of the housing  2 . The cassette receiving portion  6  is recessed downward from the upper open end of the housing  2 . A cassette  7  is attachable to and detachable from the cassette receiving portion  6 . 
     As illustrated in  FIG. 2 , the cassette receiving portion  6  includes a thermal head  60 , a drive shaft  61 , a ribbon take-up shaft  62 , and a head holder  69 . The head holder  69  is positioned at a left portion of the cassette receiving portion  6 . The thermal head  60  is provided at a left surface of the head holder  69 . The drive shaft  61  is positioned frontward of the head holder  69 , and extends in the upward/downward direction. The ribbon take-up shaft  62  is positioned rightward and rearward of the head holder  69 , and extends in the upward/downward direction. 
     A shaft  64  is provided at a position leftward of a rear portion of the cassette receiving portion  6 . The shaft  64  extends in the upward/downward direction, and pivotally movably supports a rear end portion of a platen holder  63 . The platen holder  63  rotatably supports a platen roller  65  and a conveying roller  66 . The platen roller  65  faces the thermal head  60  from the left side thereof. The conveying roller  66  is at a position frontward of the platen roller  65 , and faces the drive shaft  61  from the left side thereof. When the platen holder  63  is pivotally moved about an axis of the shaft  64 , a front end portion of the platen holder  63  is moved in a direction substantially parallel to a leftward/rightward direction so that the platen roller  65  and the conveying roller  66  are moved between a position proximity to the thermal head  60  and the drive shaft  61  (see  FIG. 2 ) and a position farther away from the thermal head  60  and the drive shaft  61  (not illustrated). 
     The drive shaft  61 , the ribbon take-up shaft  62 , the platen roller  65 , and the conveying roller  66  are connected to a conveyer motor  91  (see  FIG. 5 ) through a gear(s) (not illustrated). As the conveyer motor  91  starts to be driven, the drive shaft  61 , the platen roller  65 , and the conveying roller  66  are rotated to convey the medium  5  in a conveying direction (i.e., the frontward direction), and the ribbon take-up shaft  62  is rotated to take up an ink ribbon  8 . 
     As illustrated in  FIG. 3 , the printer  1  includes a cutter unit  10  and a discharge unit  20  those provided inside the housing  2  at a position adjacent to and rearward of the discharge opening  11 . The cutter unit  10  includes a cutting blade  12 . The cutting blade  12  is positioned downstream of both the thermal head  60  and the conveying roller  66  in the conveying direction and capable of cutting the medium  5 , That is, the cutting blade  12  is capable of completely cutting the medium  5  into two separate parts. The cutting blade  12  is connected to a cutter motor  92  (see  FIG. 5 ) through a gear(s) (not illustrated). When the cutter motor  92  starts to be driven, the cutting blade  12  cuts the medium  5 . 
     In the following description, a portion of the medium  5  cut away by the cutting blade  12  will be referred to as “segmented medium  51 ” (see  FIG. 1 ). That is, of the two separate parts of the medium  5 , the segmented medium  51  is the leading portion cut away from the remaining portion of the medium  5  and discharged to the outside of the housing  2 . 
     The discharge unit  20  includes a discharge roller  22 , a counter roller  23 , a roller holder  25 , and a movable mechanism  27 . The discharge roller  22  and the counter roller  23  are positioned downstream of the cutting blade  12  in the conveying direction. The discharge roller  22  extends in the upward/downward direction at a position leftward of the conveyed medium  5 . The counter roller  23  extends in the upward/downward direction at a position rightward of the conveyed medium  5 . The discharge roller  22  and the counter roller  23  face each other in the leftward/rightward direction with the conveyed medium  5  interposed therebetween. The discharge roller  22  and the counter roller  23  are made of elastic material. 
     The roller holder  25  supports the discharge roller  22 , and is formed with an elongated slot  26 . The movable mechanism  27  includes a rotator  28  and an eccentric shaft  29 . The eccentric shaft  29  extends upward from the rotator  28  and is inserted through the elongated slot  26 . The eccentric shaft  29  is eccentric with respect to the rotator  28 , The rotator  28  is connected to a discharge motor  93  (see  FIG. 5 ) through a gear(s) (not illustrated). A one-way clutch (not illustrated) is provided at the gear(s). The discharge motor  93  is driven and can make forward rotation and make reverse rotation. 
     As illustrated in  FIGS. 3 and 4 , in accordance with the reverse rotation of the discharge motor  93 , the rotator  28  is rotated through the gear(s), whereby the eccentric shaft  29  moves the roller holder  25  in the leftward/rightward direction. In this way, the movable mechanism  27  moves the discharge roller  22  toward and away from the counter roller  23 . In the following description, a position Where the discharge roller  22  is in the proximity to the counter roller  23  will be referred to as “nipping position” (see  FIG. 3 ), and a position where the discharge roller  22  is positioned leftward and away from the counter roller  23  will be referred to as “release position” (see  FIG. 4 ). 
     As illustrated in  FIG. 3 , the discharge roller  22  at the nipping position is in contact with the counter roller  23 . With this configuration, the medium  5  conveyed by the conveying roller  66  is nipped between the discharge roller  22  and the counter roller  23  when the discharge roller  22  is at the nipping position. As illustrated in  FIG. 4 , the discharge roller  22  is positioned away from the counter roller  23  with a gap greater than a thickness of the medium  5  when the discharge roller  22  is at the release position. Hence, the discharge roller  22  at the release position is positioned away from the conveyed medium  5 . 
     When the discharge motor  93  makes forward rotation, the discharge roller  22  rotates in a discharging direction so that the segmented medium  51  is conveyed downstream in the conveying direction. In the present embodiment, the discharging direction is a clockwise direction in plan view in  FIG. 3 . Even when the discharge motor  93  makes forward rotation, the rotation of the rotator  28  is prevented by the function of the one-way clutch. Accordingly, the discharge roller  22  rotates in the discharging direction while the position of the discharge roller  22  is maintained at the nipping position. 
     A printing line P 1  illustrated in  FIG. 3  is a position in the conveying direction where the medium  5  is nipped between the platen roller  65  and the thermal head  60 . A cutting line P 2  is a position in the conveying direction where the cutting blade  12  cuts the medium  5  to provide a segmented medium  51 . A nipping line P 3  is a position in the conveying direction where the medium  5  is nipped at a portion between the discharge roller  22  at the nipping position and the counter roller  23 . The printing line P 1 , the cutting line P 2 , and the nipping line P 3  are arrayed in this order in the conveying direction. 
     Next, the cassette  7  will next be described with reference to  FIG. 2 . Description as to the configuration of the cassette  7  will be made based on a posture of the cassette  7  attached to the cassette receiving portion  6 . Cassettes of a receptor type, a thermal type, a laminate type and the like are available as the cassette  7 .  FIG. 2  illustrates the receptor type cassette  7  as an example. 
     The cassette  7  includes a case  70 , and a drive roller  72 . The case  70  is formed with a head opening  71  and a medium ejection opening  73  at a left-front portion thereof. The head opening  71  penetrates the case  70  in the upward/downward direction, and opens leftward at a position between the medium ejection opening  73  and the drive roller  72 . The head holder  69  and the thermal head  60  are positioned within the head opening  71 . The medium ejection opening  73  is formed at a position leftward of the head opening  71 , and opens frontward. 
     The drive roller  72  is positioned at a left-front corner portion of the case  70  and extends in the upward/downward direction. The drive roller  72  has a hollow cylindrical shape and is rotatably supported by the case  70 . The drive shaft  61  is inserted into the drive roller  72 . The drive roller  72  has a left end portion exposed to an outside of the case  70  to nip the medium  5  in cooperation with the conveying roller  66 . 
     Further, the case  70  is formed with support holes  75 ,  76 ,  77 , and  78  penetrating the case  70  in the upward/downward direction. The support hole  75  rotatably supports a first medium spool  41  around which a first medium is wound. The support hole  76  is configured to rotatably support a second medium spool (not illustrated) around which a second medium is wound. The support hole  77  rotatably supports a ribbon supply spool  43  around which the ink ribbon  8  prior to printing is wound. The support hole  78  rotatably supports a ribbon take-up spool  45  around which the ink ribbon  8  already used for printing is wound. The ribbon take-up shaft  62  is inserted into the ribbon take-up spool  45 . 
     In the receptor type cassette  7 , the second medium spool for winding the second medium is not provided and thus not illustrated in the cassette  7  in  FIG. 2 , but the first medium spool  41  for winding the medium  5  as the first medium, the ribbon supply spool  43  and the ribbon take-up spool  45  are provided. As the medium  5 , a non-laminate tape, a fabric tape, a satin tape, and a heat-shrink tube are available. Regarding the thermal type cassette, the second medium spool, the ribbon supply spool  43  and the ribbon take-up spool  45  are not provided, but the first medium spool  41  is provided. A heat sensitive tape is used as the first medium. 
     Regarding the laminate type cassette, the first medium spool  41 , the second medium spool, the ribbon supply spool  43 , and the ribbon take-up spool  45  are provided. Double-sided adhesive tape is used as the first medium. A film tape is used as the second medium. The double-sided adhesive tape is superposed on the film tape at a position between the conveying roller  66  and the drive roller  72 , and is discharged together as a laminate tape. 
     With the above configuration, as the cover  3  (see  FIG. 1 ) is closed, the platen roller  65  and the conveying roller  66  are moved rightward toward and approaches the thermal head  60  and the drive shaft  61  from the left side thereof, respectively. Hence, the platen roller  65  urges both the medium  5  and the ink ribbon  8  against the thermal head  60  with the medium  5  and the ink ribbon  8  superposed on each other. The conveying roller  66  urges the medium  5  against the drive roller  72 . 
     When the ribbon take-up shaft  62  is rotated in accordance with driving of the conveyer motor  91  (see  FIG. 5 ), the ink ribbon  8  is drawn out from the ribbon supply spool  43  since the ribbon take-up spool  45  takes up the ink ribbon  8 . The drawn out ink ribbon  8  is pulled to a left-front portion of the head opening  71  through the medium ejection opening  73 , and then is moved past a portion between the platen roller  65  and the thermal head  60  to be conveyed toward the ribbon take-up spool  45 . 
     As the drive shaft  61 , the platen roller  65  and the conveying roller  66  is rotated due to the driving of the conveyer motor  91 , the medium  5  is drawn out from the first medium spool  41 . The drawn out medium  5  is pulled to the left-front portion of the head opening  71  through the medium ejection opening  73 . Then, the medium  5  is moved past the portion between the platen roller  65  and the thermal head  60  and a portion between the conveying roller  66  and the drive roller  72 , and is conveyed toward the cutter unit  10 . 
     An electrical configuration in the printer  1  will next be described with reference to  FIG. 5 . As illustrated in  FIG. 5 , the printer  1  further includes a CPU  81 . The CPU  81  functions as a processor for executing a first main routine (described later) illustrated in  FIG. 6  to perform overall control of the printer  1 . A flash memory  82 , a ROM  83 , a RAM  84 , the thermal head  60 , the conveyer motor  91 , the cutter motor  92 , the discharge motor  93 , the input portion  4 , the display portion  9 , and a medium detection sensor  99  are connected to the CPU  81 . 
     The flash memory  82  is a non-transitory storage medium that stores therein programs for the CPU  81  to execute the first main routine and printing information for the thermal head  60  to perform printing on the medium  5 . The ROM  83  is a non-transitory storage medium configured to store therein various parameters needed in the CPU  81  to execute various programs. The RAM  84  is a transitory storage medium configured to store therein temporary data of timer, counter and a flag. 
     The medium detection sensor  99  is positioned downstream of the cutting line P 2 , and specifically, positioned downstream of the nipping line P 3  (see  FIG. 3 ) in the conveying direction. The medium detection sensor  99  is a transmissive photosensor and includes a light emitting portion  991  and a light receiving portion  992 . The light emitting portion  991  and the light receiving portion  992  are positioned to oppose each other with respect to a conveying passage of the medium  5  (see  FIG. 3 ). 
     The medium detection sensor  99  is configured to output ON signal to the CPU  81  in a case where there remains the segmented medium  51  nipped at the position between the discharge roller  22  and the counter roller  23 . On the other hand, the medium detection sensor  99  is configured to output OFF signal to the CPU  81  in a case where no segmented medium  51  is nipped at the position between the discharge roller  22  and the counter roller  23 . In this way, the medium detection sensor  99  detects whether the segmented medium  51  is nipped between the discharge roller  22  and the counter roller  23 . 
     Next, the first main routine will be described with reference to  FIGS. 6 to 71 ). In a state where the cassette  7  is attached to the cassette receiving portion  6  and the cover  3  is closed, the printer  1  is powered by a user. As electric power is supplied to the printer  1 , the CPU  81  expands in the RAM  84  program stored in the flash memory  82  to start the first main routine. In  FIGS. 7A through 7D , movement of each component in the printer  1  is indicated by broken lines. 
     As illustrated in  FIG. 6 , at the beginning of the first main routine, in S 11  the CPU  81  determines whether print instruction for performing printing on the medium  5  has been acquired. The print instruction includes print information. The user inputs print instruction to the printer  1  by operating the external terminal device. When the CPU  81  determines that print instruction has not been acquired (S 11 : NO), the CPU  81  repeatedly executes the process in S 11  until the print instruction is inputted. 
     When the CPU  81  determines that the CPU  81  has acquired print instruction through the network, the cable and the like (S 11 : YES), in S 12  the discharge motor  93  is driven to make reverse rotation to move the discharge roller  22  to the release position (see  FIG. 4 ). Accordingly, the discharge roller  22  does not prevent the conveyance of the medium  5  when the print control is performed. 
     In S 13  the CPU  81  performs print control. As illustrated in  FIG. 7A , during the print control, the CPU  81  controls the conveyer motor  91  and the thermal head  60  based on the print information included in the acquired print instruction. Therefore, printing on the medium  5  by the thermal head  60  is performed while the medium  5  is conveyed by the conveying roller  66 . 
     As illustrated in  FIG. 6 , in S 14  the CPU  81  controls the discharge motor  93  to make reverse rotation so that the discharge roller  22  is moved to the nipping position (see  FIG. 3 ). As a result, the medium  5  is nipped at the position between the discharge roller  22  and the counter roller  23  as illustrated in  FIG. 7B . In this state, the CPU  81  prevents the discharge motor  93  from making forward rotation that causes rotation of the discharge roller  22 . That is, a state where the medium  5  is nipped between the discharge roller  22  and the counter roller  23  is maintained. 
     As illustrated in  FIG. 6 , in S 15  the CPU  81  drives the cutter motor  92  to cut the medium  5  by the cutting blade  12  while the forward rotation of the discharge motor  93  is prevented, i.e., the rotation of the discharge roller  22  is halted. Hence, the segmented medium  51  is provided as illustrated in  FIG. 7C . 
     Referring back to  FIG. 6 , in S 16  the CPU  81  determines whether the segmented medium  51  has been removed from the portion between the discharge roller  22  and the counter roller  23  based on a detection signal transmitted from the medium detection sensor  99 . When the CPU  81  receives ON signal from the medium detection sensor  99 , the CPU  81  determines that the segmented medium  51  has not been removed from the portion between the discharge roller  22  and the counter roller  23  (S 16 : NO), i.e., the segmented medium  51  remains at the position between the discharge roller  22  and the counter roller  23 . In this case, the process in S 16  is repeatedly executed until OFF signal is outputted from the medium detection sensor  99 . At this time, the CPU  81  cannot receive print instruction in S 11  unless the CPU  81  determines in S 16  that the segmented medium  51  is removed by the user. Consequently, new print control subsequent to the current print control is prevented. 
     When the CPU  81  receives OFF signal from the medium detection sensor  99 , the CPU  81  determines that the segmented medium  51  has been removed from the discharge roller  22  and the counter roller  23  (S 16 : YES), i.e., there is no segmented medium  51  nipped between the discharge roller  22  and the counter roller  23 . In this case, in S 17  the CPU  81  controls the discharge motor  93  to make forward rotation by a prescribed amount to cause the discharge roller  22  to be rotated in the discharging direction. 
     Normally, when the segmented medium  51  has been removed by the user from the portion between the discharge roller  22  and the counter roller  23 , the medium detection sensor  99  outputs OFF signal. However, the medium detection sensor  99  may erroneously output OFF signal in spite of the fact that the segmented medium  51  still remains at the portion between the discharge roller  22  and the counter roller  23 , i.e., the segmented medium  51  has not been removed by the user. 
     In this case, if subsequent print control is performed while the segmented medium  51  remains at the portion between the discharge roller  22  and the counter roller  23 , and if the segmented medium  51  is displaced upstream in the conveying direction (toward the cutting blade  12 ), the medium  5  printed during the subsequent print control and the remaining segmented medium  51  may overlap each other, and both the medium  5  and the remaining segmented medium  51  may be cut together by the cutting blade  12 , which may cause damages to the cutting blade  12 . Further, the newly printed medium  5  may interfere with the remaining segmented medium  51 , to cause jam of the mediums in the printer  1 . 
     In view of the foregoing, in S 17 , even if the segmented medium  51  still remains at the position between the discharge roller  22  and the counter roller  23 , the printer  1  rotates the discharge roller  22  in the discharging direction and conveys the remaining segmented medium  51  downstream in the conveying direction from the portion between the discharge roller  22  and the counter roller  23  to discharge the segmented medium  51  prior to subsequent print control is performed (see  FIG. 7D ). Hence, the printer  1  can suppress the subsequent print control from being executed in the state where the segmented medium  51  remains at the portion between the discharge roller  22  and the counter roller  23 . Consequently, tile printer  1  can avoid jam of the mediums therein and damages to the cutting blade  12 . 
     The prescribed amount (i.e., an amount of forward rotation of the discharge motor  93  in S 17 ) denotes an amount of the forward rotation corresponding to a distance in the conveying direction smaller than a distance D 1  in the conveying direction between the printing line P 1  and the nipping line P 3  and greater than a distance D 2  in the conveying direction between the cutting line P 2  and the nipping line P 3 . In other words, when the discharge motor  93  makes forward rotation by the prescribed amount in S 17 , the discharge roller  22  is rotated to convey tile segmented medium  51  by a distance smaller than the distance D 1  and greater than the distance D 2 . 
     Incidentally, the distance in the conveying direction is defined along the conveying passage of the medium  5 . In the present embodiment, the distance D 1  is a linear distance between the printing line P 1  and the nipping line P 3 , and the distance D 2  is a linear distance between the cutting line P 2  and the nipping line P 3 . 
     As illustrated in  FIG. 6 , after executing the process in S 17 , the CPU  81  returns to the process in S 11 . In this state, the CPU  81  is ready to receive new print instruction in S 11  in accordance with the rotation of the discharge roller  22  in the discharging direction in S 17 . Consequently, subsequent print control can be performed. In this way, the CPU  81  determines whether to allow subsequent control to be performed on a basis of the detection signal outputted by the medium detection sensor  99 . 
     As described above, after the print control is performed, forward rotation of the discharge motor  93  is prevented in the state where the medium  5  is nipped at the portion between the discharge roller  22  and the counter roller  23 . Hence, the cutting blade  12  can cut the medium  5  while the rotation of the discharge roller  22  is halted. As the cutter motor  92  is driven, the cutting blade  12  is caused to cut the medium  5  to provide a segmented medium  51 . Thereafter, the user can take out the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 . 
     In a case where the execution of subsequent print control is determined to be permitted (i.e., the segmented medium  51  is determined to be removed), the discharge motor  93  is driven to make forward rotation to rotate the discharge roller  22  in the discharging direction prior to start of the subsequent print control. Accordingly, even when the medium detection sensor  99  erroneously detects that the segmented medium  51  does not remain in spite of the fact that the segmented medium  51  still exists at the position between the discharge roller  22  and the counter roller  23 , the segmented medium  51  can be discharged from the portion between the discharge roller  22  and the counter roller  23  to the downstream side thereof in the conveying direction by the rotation of the discharge roller  22 . 
     Consequently, the printer  1  according to the present embodiment can suppress execution of subsequent print control in the state where the segmented medium  51  still remains at the portion between the discharge roller  22  and the counter roller  23 , thereby restraining jam of the media in the printer  1 . 
     The CPU  81  determines that execution of subsequent print control is permitted in response to detecting, through the medium detection sensor  99 , that the segmented medium  51  has been removed from the portion between the discharge roller  22  and the counter roller  23 . This configuration can prevent the subsequent print control from starting before the user removes the segmented medium  51  away from the portion between the discharge roller  22  and the counter roller  23 . Accordingly, jam of the media within the printer  1  can further be prevented. 
     The medium detection sensor  99  is positioned downstream of the discharge roller  22  in the conveying direction. Therefore, the printer  1  does not require a space for positioning the medium detection sensor  99  at a position between the cutting blade  12  and the discharge roller  22  in the conveying direction. Hence, the distance in the conveying direction between the cutting blade  12  and the discharge roller  22  can be reduced. Accordingly, a length of margin (a region in Which printing is not performed) of the medium  5  can be reduced. 
     Further, even if the medium detection sensor  99  erroneously detects absence of the segmented medium  51  due to an external light entered in the printer  1 , the segmented medium  51  can be securely discharged by the rotation of the discharge roller  22  in the discharging direction prior to start of subsequent print control, thereby avoiding jam of the mediums in the printer  1 . Thus, the printer  1  can reduce a length of margin in the medium  5  and can avoid occurrence of jam of the mediums. 
     Further, the prescribed amount of the forward rotation of the discharge motor  93  in S 17  is constant. Accordingly, even when the segmented medium  51  remains at the portion between the discharge roller  22  and the counter roller  23 , the printer  1  can securely discharge the remaining segmented medium  51  to the downstream of the discharge roller  22  and the counter roller  23  in the conveying direction. Hence, the printer  1  can further avoid occurrence of jam of the mediums. 
     The prescribed amount of the forward rotation of the discharge motor  93  in S 17  is smaller than an amount of the forward rotation of the discharge motor  93  causing the segmented medium  51  to be conveyed by the distance D 1  between the printing line P 1  and the nipping line P 3  in the conveying direction. Therefore, the printer  1  can shorten a cycle time (a period of time) until the subsequent print control is started. Hence, prolongation of the cycle time can be restrained while avoiding jam of the mediums in the printer  1 . 
     Further, the prescribed amount of the forward rotation of the discharge motor  93  in S 17  is greater than an amount of the forward rotation of the discharge motor  93  causing the segmented medium  51  to conveyed by the distance D 2  (see  FIG. 7 ) between the cutting line P 2  and the nipping line P 3  in the conveying direction. Accordingly, even when the segmented medium  51  remains at the portion between the discharge roller  22  and the counter roller  23 , the printer  1  can securely discharge the segmented medium  51  out of the portion between the discharge roller  22  and the counter roller  23  to the downstream side in the conveying direction. Thus, the printer  1  can further avoid jam of the mediums. 
     Next, a printer  1  according to a second embodiment will be described with reference to  FIG. 8 . Mechanical configuration of the printer  1  according to the second embodiment is the same as that of the printer  1  according to the first embodiment. The second embodiment is different from the first embodiment in that the CPU  81  executes a second main routine illustrated in  FIG. 8  in place of the first main routine. In the second main routine, the process in S 161  is executed instead of the process in S 16  of the first main routine. The remaining processes in S 11  to S 15  and S 17  are the same as those in the first main routine so that the description as to these processes will be omitted to avoid duplicating description. As the printer  1  is powered by the user, the CPU  81  expands in the RAM  84  program stored in the flash memory  82  to start the second main routine. 
     As illustrated in  FIG. 8 , after executing the process in S 15 , in S 161  the CPU  81  determines whether removal complete instruction has been acquired. Here, after the user removes the segmented medium  51  away from the portion between the discharge roller  22  and the counter roller  23 , the user inputs removal complete instruction to the printer  1  by operating the input portion  4 . When the CPU  81  determines in S 161  that the removal complete instruction has not been acquired (S 161 : NO), the CPU  81  repeatedly executes the process in S 161  until the removal complete instruction has been inputted. Accordingly, the CPU  81  cannot receive new print instruction in S 11  unless the CPU  81  determines that the removal complete instruction has been acquired in S 161 . Thus, execution of subsequent print control is prevented. 
     On the other hand, when the CPU  81  determines that the removal complete instruction has been acquired (S 161 : YES), the CPU  81  advances to the process in S 17 . Hence, the CPU  81  is allowed to receive new print instruction in S 11  in accordance with the rotation of the discharge roller  22  in the discharging direction in S 17 , whereby subsequent print control can be performed. In this way, the CPU  81  determines whether the subsequent print control can be performed based on whether removal complete instruction has been acquired from the user. 
     Similar to the first embodiment, according to the second embodiment, when the CPU  81  determines that execution of subsequent print control is permitted, the discharge motor  93  is driven to make forward rotation to rotate the discharge roller  22  in the discharging direction before starting the subsequent print control. As a result, occurrence of jam of the mediums in the printer  1  can be restrained. 
     Further, in the second embodiment, after removing the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 , the user inputs removal complete instruction into the printer  1 . Therefore, the printer  1  can securely prevent subsequent print control from starting before the user removes the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 . This operation can further restrain occurrence of jam of the mediums in the printer  1 . 
     Next, a printer  1  according to a third embodiment will be described with reference to  FIG. 9 . Note that mechanical configuration of the printer  1  according to the third embodiment is the same as that of the first embodiment and the second embodiment. The third embodiment differs from the first embodiment in that a third main routine is executed instead of the first main routine in the first embodiment. In the third main routine, the CPU  81  executes the process in S 162  and S 172  instead of the process in S 16  and S 17  in the first main routine, respectively. In  FIG. 9 , the processes the same as those in the first embodiment will be designated by the same step numerals as those shown in  FIG. 6  to avoid duplicating description. When the printer  1  is powered by the user, the CPU  81  expands in the RAM  84  program stored in the flash memory  82  to start the third main routine. 
     As illustrated in  FIG. 9 , after executing the process in S 15 , in S 162  the CPU  81  determines whether new print instruction has been acquired. After the user removes the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 , the user to inputs new print instruction to the printer  1  by operating the external terminal device. When the CPU  81  determines that new print instruction has not been acquired (S 162 : NO), the process in S 162  is repeatedly executed until the new print instruction is inputted. Accordingly, execution of subsequent print control is prevented until the CPU  81  determines that print instruction has been acquired in S 162 . 
     When the CPU  81  determines that the CPU  81  has acquired new print instruction (S 162 : YES), in S 172  the CPU  81  drives the discharge motor  93  to make forward rotation by the prescribed amount to rotate the discharge roller  22  in the discharging direction, and then the CPU  81  returns to the process in S 12 , whereupon subsequent print control is allowed. Accordingly, subsequent print control is allowed to be executed in response to the rotation of the discharge roller  22  in the discharging direction in S 172 . In this way, the CPU  81  determines whether execution of subsequent print control is to be permitted on a basis of whether new print instruction has been inputted. 
     Similar to the first and second embodiments, according to the third embodiment, when the execution of subsequent print control is determined to be permitted, the discharge motor  93  is driven to make forward rotation to rotate the discharge roller  22  in the discharging direction before starting subsequent print control. As a result, as in the first and second embodiments, occurrence of jam of the mediums can be securely obviated according to the printer  1  in the third embodiment. 
     According to the third embodiment, after removing the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 , the user inputs new print instruction into the printer  1 . Therefore, the printer  1  can prevent subsequent print control from starting before the user removes the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 . Hence, occurrence of jam of the mediums in the printer  1  can further be restrained. After the user removes the segmented medium  51  from the portion between the discharge roller  22  and the counter roller  23 , the user can urge the printer  1  to execute subsequent print control just by inputting a single instruction (i.e., new print instruction) to the printer  1 . 
     While the description has been made in detail with reference to the first through third embodiments, it would be apparent to those skilled in the art that various changes and modifications may be made thereto. 
     For example, after executing the process in S 15  and before the process in S 17 , the CPU  81  may execute both the processes in S 16  and S 161 . In this case, after the process in S 15 , the CPU  81  determines that the segmented medium  51  has been removed in S 16  and that removal complete instruction has been acquired in S 161 , and then proceeds to the process in S 17 . Further, in the first and second main routines, the CPU  81  returns to the process in S 11  after the process in S 17  is executed. However, the process in S 17  may be executed after the process in S 11  and before the process in S 12 , not before the process in S 11 . 
     Further, the prescribed amount of the forward rotation of the discharge motor  93  may be greater than the amount of the forward rotation of the discharge motor  93  causing the segmented medium  51  to be conveyed by the distance D 1 . That is, the segmented medium  51  may be conveyed in S 17  by a distance greater than the distance D 1 . In this case, the segmented medium  51  can be securely removed from the portion between the discharge roller  22  and the counter roller  23  before subsequent print control is executed even if the segmented medium  51  still remains at the portion between the discharge roller  22  and the counter roller  23 . 
     Further, the prescribed amount of the forward rotation of the discharge motor  93  may be smaller than the amount of the forward rotation of the discharge motor  93  causing the segmented medium  51  to be conveyed by the distance D 2 . That is, the segmented medium  51  may be conveyed in S 17  by a distance smaller than the distance D 2 . In the latter case, the cycle time can be reduced while the segmented medium  51  can be discharged from the portion between the discharge roller  22  and the counter roller  23  prior to start of subsequent print control. 
     In the first through third embodiments, the user inputs print instruction by operating the external terminal device. However, the print instruction may be inputted into the printer  1  by the user&#39;s operation of the input portion  4 . Further, in the second embodiment, the removal complete instruction is inputted into the printer  1  by the user operating the input portion  4 . However, the user may input the removal complete instruction into the printer  1  by operating the external terminal device. 
     The discharge roller  22  at the nipping position may be positioned to face the counter roller  23  with a gap smaller than the thickness of the medium  5 . Further, the discharge roller  22  at the release position may be separated from the counter roller  23  with a gap smaller than the thickness of the medium  5  provided that a load applied by the discharge roller  22  to the medium  5  to urge the medium  5  toward the counter roller  23  is smaller than that applied by the discharge roller  22  at the nipping position. 
     Further, the discharge roller  22  may not be movable between the nipping position and the release position. For example, the discharge roller  22  may be immovably positioned to be in contact with the counter roller  23 , or may be immovably positioned to be spaced away from the counter roller  23  with a gap smaller than the thickness of the medium  5 . The counter roller  23  may be movable relative to the discharge roller  22 . Alternatively, both the discharge roller  22  and the counter roller  23  may be movable. Further, components for nipping the medium  5  during cutting operation by the cutting blade  12  may be provided in addition to the discharge roller  22  and the counter roller  23 . 
     The counter roller  23  may be a member that is not rotatable, i.e., may not be a roller. In this case, a plate-like member may be employed instead of the counter roller  23 . Further, at least one of the discharge roller  22  and the counter roller  23  may be formed of a material other than elastic material. The printer  1  may not be provided with the cutter motor  92 , but a user may manually operate a cutting blade to cut the medium  5 . In this case, a sensor for detecting that the cutter blade is operated by the user may be provided. 
     According to the first through third embodiments, a transmissive photosensor is used as the medium detection sensor  99 . However, a reflection type photosensor, and a mechanical switch are also available as the medium detection sensor  99 . 
     Further, instead of the CPU  81  as the processor, a microcomputer, ASIC (Application Specific integrated Circuits), and FPGA (Field Programmable Gate Array) are also available. Further, each of the first through third main routines may be executed by performing distributed processing using a plurality of processors. Any type of storage media can be employed as the non-transitory storage medium regardless of a period of time during which the medium can store information, as long as the media are capable of storing data. The non-transitory storage medium may not include a transitory storage medium such as a transmitted signal. The program may be downloaded through a server connected to a network, i.e., may be transmitted in the form of transmitted signals, and may be stored in the flash memory  82 . In the latter case, the program may be stored in a non-transitory storage medium such as a hard disc provided in the server. Further, the above-described embodiments may be combined together avoiding any technical confliction. 
     The thermal head  60  is an example of the printing head. The conveying roller  66  is an example of the conveyor. The discharge roller  22  is an example of the discharge roller. The cutting blade  12  is an example of a cutter. The discharge roller  22  is an example of the discharge roller. The counter roller  23  is an example of the counter roller. The discharge motor  93  is an example of a driver. The CPU  81  is an example of the controller. The CPU  81  that executes the process in S 13  is an example of the (a) controlling. The print control first executed by the CPU  81  is an example of the first print control. The subsequent control is an example of the second print control. The CPU  81  that executes the process in S 14  is an example of the (b) driving. The CPU  81  that executes the process in S 17  is an example of the (c) driving. The medium detection sensor  99  is an example of the sensor. The CPU  81  that executes the process in S 12  is an example of the (a) controlling. The CPU  81  that executes the process in S 13  is an example of the (b) controlling. The CPU  81  that executes the process in S 14  is an example of the (c) controlling. The CPU  81  that executes the process in S 15  is an example of the (d) controlling. The CPU  81  that executes the process in S 16  is an example of the (e) preventing. The CPU  81  that executes the process in S 17  is an example of the (f) controlling. The CPU  81  that executes the process in S 17  to S 11  is an example of the (g) permitting.