Overheat Protection Patents (Class 400/124.03)
  • Patent number: 9802427
    Abstract: Printer is provided having support base on which print media travels. Printer includes thickness detection module and processor. Thickness detection module includes pinch arm assembly with pinch arm having first and second ends, encoder, and proximate dual channel encoder sensor. First end is biased toward support base. Encoder with number of circumferentially spaced line pairs is disposed at second end. Pinch arm and encoder configured to rotate in response to engagement of pinch arm with at least print media portion. Dual channel encoder sensor configured to detect rotation direction and encoder count and output signal representing encoder count. Encoder count is number of circumferentially spaced line pairs that pass by dual channel encoder sensor as pinch arm and encoder rotate. Processor is communicatively coupled to dual channel encoder sensor and configured to receive signal and calculate print media thickness of portion from encoder count using conversion factor.
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: October 31, 2017
    Assignee: Datamax-O'Neil Corporation
    Inventors: Boon Kheng Lim, Aravindkumar Harinarayanan, Danny Lim
  • Patent number: 8767027
    Abstract: In one embodiment, a method for preventing hammer coils of a line printer hammer bank from overheating during printing includes establishing the maximum allowable temperature threshold of any given hammer coil, monitoring the temperature of all hammer coils during printing, keeping a moving average of dots printed per unit time on each hammer coil, and if one or more coils reach a temperature higher than the threshold, determining the current maximum dot-per-hammer density that the hot coils can print per stroke of the hammer bank that will enable them to cool down adequately from their current temperatures. The rate of printing is restricted to this current established maximum dot-per-hammer density on only those coils which have a temperature at or above the maximum allowable temperature, minus a suitable hysteresis.
    Type: Grant
    Filed: October 17, 2012
    Date of Patent: July 1, 2014
    Assignee: Printronix, Inc.
    Inventors: Greg Anderson, Connie Bowen, Raul Velasquez
  • Patent number: 7980774
    Abstract: A recording control device includes a head driving circuit, a temperature detector, and a controller. The head driving circuit includes a power supply that supplies a driving current to a plurality of driving coils used for driving a plurality of recording wires provided in a recording head. An induced current flows through a circuit which is connected to the plurality of driving coils when the driving current to the driving coils stops. The temperature detector detects a temperature of heat generated in the circuit due to the induced current, and the controller controls an operation of the recording head based on the temperature detected by the temperature detector.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: July 19, 2011
    Assignee: Seiko Epson Corporation
    Inventors: Motohiro Nakamaki, Mamoru Wada
  • Publication number: 20100119279
    Abstract: A recording control device includes a head driving circuit, a temperature detector, and a controller. The head driving circuit includes a power supply that supplies a driving current to a plurality of driving coils used for driving a plurality of recording wires provided in a recording head. An induced current flows through a circuit which is connected to the plurality of driving coils when the driving current to the driving coils stops. The temperature detector detects a temperature of heat generated in the circuit due to the induced current, and the controller controls an operation of the recording head based on the temperature detected by the temperature detector.
    Type: Application
    Filed: January 19, 2010
    Publication date: May 13, 2010
    Applicant: Seiko Epson Corporation
    Inventors: Motohiro Nakamaki, Mamoru Wada
  • Patent number: 7665919
    Abstract: A recording control device includes a head driving circuit, a temperature detector, and a controller. The head driving circuit includes a power supply that supplies a driving current to a plurality of driving coils used for driving a plurality of recording wires provided in a recording head. An induced current flows through a circuit which is connected to the plurality of driving coils when the driving current to the driving coils stops. The temperature detector detects a temperature of heat generated in the circuit due to the induced current, and the controller controls an operation of the recording head based on the temperature detected by the temperature detector.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: February 23, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Motohiro Nakamaki, Mamoru Wada
  • Patent number: 7014375
    Abstract: A tape print apparatus is capable of setting a weak voltage value, serving as a criterion on indicating a power weakness condition on a display, to an appropriate voltage value based on various kinds of usage conditions by considering that the degree of consumption of drive power differs depending on the usage conditions of a tape print apparatus.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: March 21, 2006
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Tsuyoshi Nagae, Takashi Horiuchi
  • Patent number: 6695495
    Abstract: An ink density closed loop control system for an ink ribbon of an impact printer having a reservoir roller formed of an ink absorbent material with at least one or more channels within the reservoir roller fluidly connected to a pump and ink supply. A transfer roller can contact the reservoir roller for imparting ink to the ink ribbon. A sensor senses the relative amount of ink on the print ribbon and an electrical drive responsive to the sensor drives the pump for a flow of ink to the one or more channels. The sensor can sense ink on different segments of the ribbon and, with two or more channels in the reservoir roller can distribute ink to two or more segments of the reservoir roller depending upon the ink sensed at a particular segment of the ribbon. A further enhancement of this invention provides a multi-viscosity ink to compensate for changes in ambient temperature conditions.
    Type: Grant
    Filed: March 12, 2003
    Date of Patent: February 24, 2004
    Assignee: Printronix, Inc.
    Inventors: Dennis R. White, Jeng-Dung Jou, Lihu Chiu, Gordon B. Barrus, Y. Grant Chang
  • Patent number: 6659663
    Abstract: For a print head in an impact dot printer, a drive transistor 33 is connected in series to a head coil 59 that drives a print wire, and a pulse 32 is used to turn the drive transistor 33 on and off. Thus, the drive current i is supplied to the head coil 59 to drive the print wire. The input end of a DC/DC converter 2 is connected to the juncture of the head coil 59 and the drive transistor 33, and the output end of the DC/DC converter 2 is connected to the juncture of a power source 34 and the head coil 59. The DC/DC converter 2 clamps, at a constant level, e.g., 90V, the inductive electromotive force of a high voltage that is generated by the head coil 59 when the drive transistor 33 is rendered off. Then, the DC/DC converter 2 transforms the clamped voltage to a voltage equivalent to the voltage level of the power source 34, e.g., 35V.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: December 9, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Hiroshi Shirotori, Hisashi Watamura