# US 12,759,331 B2 · Adaptive ribbon speed control systems and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,331 B2 - Document ID: US12759331B2 - Status: Granted - Kind: B2 - Application number: 18/983,099 - Filed: 2024-12-16 - Published: 2025-04-10 - Granted: 2026-10-13 - Earliest claimed: 2023-02-27 - Assignees: Printronix, Inc. - Applicants: Printronix, LLC - Inventors: Yu-Min Grant Chang; Robert Ovcharenko; Lee Fang Chong; Ming Ming Yin - Web page: https://patentgrep.com/patent/US12759331B2 ## CPC - B41J 33/36: with means for adjusting feeding rate - B41J 32/00: Ink-ribbon cartridges - B41J 32/02: for endless ribbons - B41J 33/14: Ribbon-feed devices or mechanisms - B41J 33/22: by gears or pulleys - B41J 33/34: driven by motors independently of the machine as a whole - B41J 35/36: Alarms, indicators, or feed disabling devices responsive to ink ribbon breakage or exhaustion - B41J 2203/01: Inspecting a printed medium or a medium to be printed using a sensing device - G06K 15/10: by matrix printers {(G06K15/028 takes precedence)} - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS ## Abstract Systems and methods related to adaptive ribbon speed control for a line matrix impact printer are provided. A ribbon cartridge includes a ribbon configured to be driven at a ribbon speed, and a ribbon gear configured to rotate with movement of the ribbon. The ribbon includes a ribbon joint patch detectable via a first sensor to determine a first ribbon speed of the ribbon. Rotation of the ribbon gear is detectable via a second sensor to determine a second ribbon speed of the ribbon. A target ribbon speed is determined based on at least one print job characteristic. A current ribbon speed is determined based on the first ribbon speed and the second ribbon speed. The ribbon speed is adjusted based on a difference between the current ribbon speed and the target ribbon speed. Associated systems and methods are also provided. ## Claims ### Claim 1 A system comprising: a ribbon cartridge comprising a ribbon configured to be driven at a ribbon speed; one or more ribbon speed sensors; and a controller configured to: determine a target ribbon speed based on at least one print job characteristic, determine a current ribbon speed via the one or more ribbon speed sensors, and adjust the ribbon speed based on a difference between the current ribbon speed and the target ribbon speed. ### Claim 2 (depends on 1) The system of claim 1, wherein the controller is further configured to detect a ribbon fault based on a comparison between the current ribbon speed and a motor speed of a drive system. ### Claim 3 (depends on 2) The system of claim 2, wherein the controller is further configured to provide a ribbon fault indication based on a difference between the current ribbon speed and the motor speed exceeding a threshold difference. ### Claim 4 (depends on 1) The system of claim 1, wherein the controller is configured to determine the current ribbon speed via two or more ribbon speed sensors, wherein the two or more ribbon speed sensors comprise: a first sensor configured to detect a ribbon joint patch of the ribbon; and a second sensor configured to detect a rotational speed of a ribbon gear. ### Claim 5 (depends on 4) The system of claim 4, wherein: the first sensor comprises an optical sensor; and the second sensor comprises a Hall sensor. ### Claim 6 (depends on 1) The system of claim 1, wherein the at least one print job characteristic comprises at least one of a dot coverage rate, a print tip size, a print tip spacing, a ribbon cartridge property, a print medium property, an ink replenish rate, an ink consumption rate, a shuttle speed, or a shuttle direction. ### Claim 7 (depends on 1) The system of claim 1, wherein the system comprises a line matrix impact printer. ### Claim 8 (depends on 1) The system of claim 1, wherein the one or more ribbon speed sensors comprise a first ribbon speed sensor and a second ribbon sensor. ### Claim 9 (depends on 8) The system of claim 8, wherein the first ribbon speed sensor is located at an entry location of the ribbon into the ribbon cartridge and the second ribbon speed sensor is located at an exit location of the ribbon out of the ribbon cartridge. ### Claim 10 A method for adjusting a ribbon speed, comprising: determining a target ribbon speed based on at least one print job characteristic; determining a current ribbon speed via one or more ribbon speed sensors, and adjusting the ribbon speed based on a difference between the current ribbon speed and the target ribbon speed. ### Claim 11 (depends on 10) The method of claim 10, further comprising detecting a ribbon fault based on a comparison between the current ribbon speed and a motor speed of a drive system. ### Claim 12 (depends on 11) The method of claim 11, further comprising providing a ribbon fault indication based on a difference between the current ribbon speed and the motor speed exceeding a threshold difference. ### Claim 13 (depends on 10) The method of claim 10, further comprising determining the current ribbon speed via two or more ribbon speed sensors, wherein the two or more ribbon speed sensors comprise: a first sensor configured to detect a ribbon joint patch of the ribbon; and a second sensor configured to detect a rotational speed of a ribbon gear. ### Claim 14 (depends on 13) The method of claim 13, wherein: the first sensor comprises an optical sensor; and the second sensor comprises a Hall sensor. ### Claim 15 (depends on 10) The method of claim 10, wherein the at least one print job characteristic comprises at least one of a dot coverage rate, a print tip size, a print tip spacing, a ribbon cartridge property, a print medium property, an ink replenish rate, an ink consumption rate, a shuttle speed, or a shuttle direction. ### Claim 16 (depends on 10) The method of claim 10, wherein the ribbon speed is adjusted in a line matrix impact printer. ### Claim 17 (depends on 10) The method of claim 10, further comprising determining the current ribbon speed via a first ribbon speed sensor and a second ribbon speed sensor, wherein the first ribbon speed sensor is located at an entry location of the ribbon into a ribbon cartridge and the second ribbon speed sensor is located at an exit location of the ribbon out of the ribbon cartridge. ### Claim 18 A non-transitory machine-readable memory comprising software instructions that when executed by a controller cause a system to perform operations comprising: determining a target ribbon speed based on at least one print job characteristic; determining a current ribbon speed via one or more ribbon speed sensors, and adjusting the ribbon speed based on a difference between the current ribbon speed and the target ribbon speed. ### Claim 19 (depends on 18) The non-transitory machine-readable memory of claim 18, wherein the operations further comprise detecting a ribbon fault based on a comparison between the current ribbon speed and a motor speed of a drive system. ### Claim 20 (depends on 19) The non-transitory machine-readable memory of claim 19, wherein the operations further comprise providing a ribbon fault indication based on a difference between the current ribbon speed and the motor speed exceeding a threshold difference.