# US 8,783,982 B2 · Media processing device, control method for a media processing device, and recording medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,982 B2 - Document ID: US8783982B2 - Status: Granted - Kind: B2 - Application number: 13/234,850 - Filed: 2011-09-16 - Published: 2012-03-22 - Granted: 2014-07-22 - Earliest claimed: 2010-09-17 - Assignees: Seiko Epson Corporation - Applicants: Yoshiki Ushiyama - Inventors: Yoshiki Ushiyama - Web page: https://patentgrep.com/patent/US8783982B2 ## CPC - B41J 19/205: {Position or speed detectors therefor} - B41J 3/44: Typewriters or selective printing mechanisms having dual functions or combined with, or coupled to, apparatus performing other functions - B41J 3/60: for printing on both faces of the printing material - B41J 19/207: {Encoding along a bar} - B41J 29/38: Drives, motors, controls or automatic cut-off devices for the entire printing mechanism - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract A media processing device and control method for a media processing device enable accurately setting and detecting the home position of a carriage without using a dedicated sensor. Scales 56, 62 having a plurality of wide slits 65 formed at equal intervals and a narrow slit 66 at one end 56A, 62A are disposed parallel to carriage shafts 53, 60. Carriage sensors 55, 61 scan the scales 56, 62 while the carriages 52, 58 move bidirectionally, and detect the wide slits 65 and the narrow slits 66. To initialize the carriages 52, 58, the carriages 52, 58 are moved specific distance L away from the one end 56A, 62A, and the carriages 52, 58 are then reversed and moved until the carriage sensors 55, 61 detect the narrow slits 66. The home position HP is set based on where the narrow slit 66 is detected. ## Claims ### Claim 1 A media processing device comprising: a conveyance path configured to convey a recording medium; on one side of the conveyance path a first recording head configured to record on one side of the recording medium, a first carriage configured to carry the first recording head, a first conveyance unit configured to move the first carriage on a first carriage shaft, a first scale having a plurality of first slits of a specific width formed with a specific interval therebetween, and at one end thereof a second slit of a different width than the first slit, and a first detection unit that is carried on the first carriage and detects the first slits and the second slit of the first scale; and on the other side of the conveyance path a second recording head configured to record on the other side of the recording medium, a second carriage configured to carry the second recording head, a second conveyance unit configured to move the second carriage on a second carriage shaft, a second scale having a plurality of third slits of a specific width formed with a specific interval therebetween, and at one end thereof a fourth slit of a different width than the third slit, and a second detection unit that is carried on the second carriage and detects the third slits and the fourth slit of the second scale; and a control unit configured to drive the first conveyance unit and moves the first carriage a first specific distance away from the one end of the first scale, to reverse and move the first carriage at least until the first detection unit detects the second slit, to set the first carriage home position based on the position where the second slit was detected, to drive the second conveyance unit and moves the second carriage a second specific distance away from the one end of the second scale, to reverse and move the second carriage at least until the second detection unit detects the fourth slit, and to set the second carriage home position based on the position where the fourth slit was detected; wherein the first scale and the second scale are disposed so that the end of the first scale to which the second slit is disposed, and the end of the second scale to which the fourth slit is disposed, are at the same end on opposite sides of the conveyance path. ### Claim 2 (depends on 1) The media processing device described in claim 1, wherein: the first conveyance unit has a first stepper motor, and the control unit detects conveyance errors of the first conveyance unit based on a first number of steps the first stepper motor was driven, and the distance the first carriage moved, which is obtained based on detection of first slits by the first detection unit; and the second conveyance unit has a second stepper motor, and the control unit detects conveyance errors of the second conveyance unit based on a second number of steps the second stepper motor was driven, and the distance the second carriage moved, which is obtained based on detection of third slits by the second detection unit. ### Claim 3 (depends on 1) The media processing device described in claim 1, wherein: the control unit does not detect conveyance errors when the first carriage or second carriage accelerates or decelerates. ### Claim 4 (depends on 1) The media processing device described in claim 1, wherein the first slits of the first scale and the third slits of the second scale are the same width; and the second slit of the first scale and the fourth slit of the second scale are the same width. ### Claim 5 (depends on 1) The media processing device described in claim 1, wherein the control unit supplies power to the first detection unit or second detection unit only when the first conveyance unit or the second conveyance unit is driven. ### Claim 6 (depends on 1) The media processing device described in claim 1, wherein the first specific distance is a distance greater than at least the sum of the first slit width, second slit width, and the gap between the first slit and second slit; and the second specific distance is a distance greater than at least the sum of the third slit width, fourth slit width, and the gap between the third slit and fourth slit. ### Claim 7 A control method for a media processing device including a conveyance path that conveys a recording medium, on one side of the conveyance path a first recording head that records on one side of the recording medium, a first carriage that carries the first recording head, a first conveyance unit that moves the first carriage on a first carriage shaft, a first scale having a plurality of first slits of a specific width formed with a specific interval therebetween, and at one end thereof a second slit of a different width than the first slit, and a first detection unit that is carried on the first carriage and detects the first slits and the second slit of the first scale, and on the other side of the conveyance path a second recording head that records on the other side of the recording medium, a second carriage that carries the second recording head, a second conveyance unit that moves the second carriage on a second carriage shaft, a second scale having a plurality of third slits of a specific width formed with a specific interval therebetween, and at one end thereof a fourth slit of a different width than the third slit, and a second detection unit that is carried on the second carriage and detects the third slits and the fourth slit of the second scale, wherein the first scale and the second scale are disposed so that the end of the first scale to which the second slit is disposed, and the end of the second scale to which the fourth slit is disposed, are at the same end on opposite sides of the conveyance path, the control method comprising: moving the first carriage a first specific distance away from the one end of the first scale, reversing and moving the first carriage at least until the first detection unit detects the second slit, and setting the first carriage home position based on the position where the second slit was detected, by the first conveyance unit; and moving the second carriage a second specific distance away from the one end of the second scale, reversing and moving the second carriage at least until the second detection unit detects the fourth slit, and setting the second carriage home position based on the position where the fourth slit was detected, by the second conveyance unit. ### Claim 8 (depends on 7) The control method for a media processing device described in claim 7, comprising further steps of: detecting conveyance errors of the first conveyance unit based on a first number of steps a first stepper motor of the first conveyance unit was driven, and the distance the first carriage moved, which is obtained based on detection of first slits by the first detection unit; and detecting conveyance errors of the second conveyance unit based on a second number of steps a second stepper motor of the second conveyance unit was driven, and the distance the second carriage moved, which is obtained based on detection of third slits by the second detection unit. ### Claim 9 (depends on 8) The control method for a media processing device described in claim 8, wherein conveyance errors are not detected when the first carriage or second carriage accelerates or decelerates. ### Claim 10 (depends on 7) The control method for a media processing device described in claim 7, wherein the first slits of the first scale and the third slits of the second scale are the same width; and the second slit of the first scale and the fourth slit of the second scale are the same width. ### Claim 11 (depends on 7) The control method for a media processing device described in claim 7, wherein the control unit supplies power to the first detection unit or second detection unit only when the first conveyance unit or the second conveyance unit is driven. ### Claim 12 (depends on 7) The control method for a media processing device described in claim 7, wherein the first specific distance is a distance greater than at least the sum of the first slit width, second slit width, and the gap between the first slit and second slit; and the second specific distance is a distance greater than at least the sum of the third slit width, fourth slit width, and the gap between the third slit and fourth slit. ### Claim 13 (depends on 7) The control method for a media processing device described in claim 7, wherein the recording medium is a check on which magnetic ink characters are recorded; a reading unit is disposed to the conveyance path to read magnetic ink characters from checks; the first recording head is disposed to the conveyance path on the opposite side as the reading unit, and based on the home position of the first carriage records on the side of the check on which magnetic ink characters are not recorded; and the second recording head is disposed to the conveyance path on the same side as the reading unit, and based on the home position of the second carriage records on the side of the check on which magnetic ink characters are recorded. ### Claim 14 A non-transitory computer readable storage medium storing a program executed by a control unit that controls parts of a media processing device including a conveyance path that conveys a recording medium, on one side of the conveyance path a first recording head that records on one side of the recording medium, a first carriage that carries the first recording head, a first conveyance unit that moves the first carriage on a first carriage shaft, a first scale having a plurality of first slits of a specific width formed with a specific interval therebetween, and at one end thereof a second slit of a different width than the first slit, and a first detection unit that is carried on the first carriage and detects the first slits and the second slit of the first scale, and on the other side of the conveyance path a second recording head that records on the other side of the recording medium, a second carriage that carries the second recording head, a second conveyance unit that moves the second carriage on a second carriage shaft, a second scale having a plurality of third slits of a specific width formed with a specific interval therebetween, and at one end thereof a fourth slit of a different width than the third slit, and a second detection unit that is carried on the second carriage and detects the third slits and the fourth slit of the second scale, wherein the first scale and the second scale are disposed so that the end of the first scale to which the second slit is disposed, and the end of the second scale to which the fourth slit is disposed, are at the same end on opposite sides of the conveyance path, the program comprising steps of: moving the first carriage a first specific distance away from the one end of the first scale, reversing and moving the first carriage at least until the first detection unit detects the second slit, and setting the first carriage home position based on the position where the second slit was detected, by the first conveyance unit; and moving the second carriage a second specific distance away from the one end of the second scale, reversing and moving the second carriage at least until the second detection unit detects the fourth slit, and setting the second carriage home position based on the position where the fourth slit was detected, by the second conveyance unit.