Abstract:
An improved DC servo motor driver circuit is provided that is based upon a readily available conventional stepper motor driver integrated circuit (IC). The IC's current "Sense" line that is usually connected to a low value resistor is instead tied to DC common or to ground. The IC's "Comparator" input, which is usually connected to the current Sense line, is connected to a pulsing input signal that provides the comparators with an appropriate voltage to make the comparators believe that more current is required at the very times the remaining portions of the circuit are attempting to provide current to the DC servo motor. An RC circuit is provided at the IC's "Pulse Time" input so that the monostable timer is properly triggered. An ASIC provides the proper logic signals to not only control the direction of the DC servo motor, but also to provide pulses of an appropriate frequency and duty cycle to emulate a pulse-width modulator. The direction signal is connected to the "Phase" input, and the pulse-width modulated signal is provided to interface circuitry that drives the Comparator and Pulse Time inputs. The output transistors in an H-bridge driver stage within the stepper motor driver IC are controlled so as to provide pulse-width modulated voltage pulses across the motor winding of the DC servo motor, such that this DC servo motor can operate exactly as if it were being driven by an integrated circuit that was specifically designed to act as a DC servo motor driver circuit. The average current supplied over time to the DC servo motor is directly related to the duty cycle of the pulse-width modulated voltage pulses across its winding, which in turn is directly related to the duty cycle of the main input control signal.
Abstract:
A resolution quality redefinition control system for a multi function scanner/printer controls a plurality of functions executable such as scanning, printing, copying and faxing. Multiple resolution qualities may be selected by a user for any of the functions through a user input in communication with the controller. A designated quality resolution may not be appropriate for a designated function, however. Some of the functions have an optimal resolution and/or a significant range of resolutions. When the designated quality resolution is not appropriate for a designated function, the controller re-defines the designated quality resolution as an execute resolution for each execution of one of the functions. The execute resolution may be a higher one of the multiple designatable resolutions when the designated resolution is below the optimal resolution but within said significant range, may be a lower of the multiple designatable resolutions when the designated resolution is above the optimal resolution but within said significant range, may be a maximum resolution, may be a minimum resolution or may be a single optimal resolution.
Abstract:
A RFID linking device-based switchable sensor can be used to detect an unseated condition of one component with another component. The switchable sensor includes a RFID linking device, such as a RFID tag, with an electrical circuitry mountable on the one component and a switchable device incorporated with two portions of the electrical circuitry physically and electrically separated from one another such that the switchable device is exposed and normally in a first condition disabling the RFID linking device to a communicatively unavailable state. The switchable device is accessible from externally of the switchable sensor and thus switchable to a second condition, due to contact with an actuator element on the other component, enabling the RFID linking device to a communicatively available state in response to the one component being placed in the seated condition with the other component.
Abstract:
The invention includes a method and system for improving the output quality of an image forming device. The method includes comparing an amount of speckle present in the images with a predefined amount of speckle. Thereafter, it is evaluated whether an adjustment of an angle of inclination of an image capture assembly in the image forming device is required for improving the output quality of the images. Accordingly, the height of one or more spacers of a spacer assembly may be altered for inclining the image capture assembly with respect to a transparent surface on which an object to be scanned by the image forming device is placed. The height of the spacer assembly may be adjustable by a user or pre-set to an optimum level for reducing the speckle to a value less than or equal to the predefined amount of speckle.
Abstract:
Multiple enhancements are provided to a smart copy function of an imaging device to improve performance by making it operate in a time efficient manner. The enhancements include determining pre-positioning of the scan bar based upon the content type setting in the user interface. The smart copy function is also enhanced by determining when to implement and implementing a second pre-scan at a higher resolution when misidentification occurs. Another enhancement uses original size and edge to edge properties to determine content of the original document, which then allows optimal selection of the final copy scan and print parameters.
Abstract:
A method of detecting a media change includes the steps of comparing a previous media condition to a current media condition, detecting a media change when the previous media condition is in one state and the current media condition is not said one state and, prompting a user to make appropriate menu selections when the media change is detected.
Abstract:
An ink detection sensor for an ink jet printer includes two terminals defining a substantially linear gap therebetween. An ink support device supports ink in the gap between the terminals. An electrical measuring device detects a change in an electrical resistance between the terminals when ink is supported in the gap by the ink support device.
Abstract:
Electromigration within heater resistors of printheads is prevented by taking into account a resistance degradation characteristic of the heater resistors. In one method a burn in operation of the printhead heater resistors is provided in order to bring the heater resistor resistance to a substantially stable resistance value. Alternatively, a method of controlling firing of a heater resistor within a printhead of an ink jet printer involves establishing a desired current density or maximum acceptable current density for the heater resistor. A resistance of the heater resistor is thereafter monitored during printing operations. Based at least in part upon the monitored resistance, a firing voltage across the heater resistor is adjusted in order to maintain the desired current density through the heater resistor or in order to hold current density through the heater resistor at or below the maximum acceptable current density.
Abstract:
A driver circuit for an matrix type inkjet printhead having a plurality of first heater resistors arranged in a matrix comprising a plurality of groups of heater resistors. The driver circuit comprises a plurality of first switches and a plurality of second switches. Each of the plurality of first switches is coupled to a heater resistor in each of the plurality of groups and is responsive to one of a plurality of first control signals to supply a current to the associated heater resistor. Each of the plurality of second switches is associated with one of the plurality of first switches, and comprises an input, an output and a gate. The input of each of the plurality of second switches is coupled to one of the plurality of first control signals, and the output of each of the plurality of second switches is coupled to the plurality of first switches for one of the plurality of groups of heater resistors. Each of the plurality of second switches is responsive to one of a plurality of second control signals coupled to the gate thereof to transfer one of the plurality of first control signals coupled to its input to an associated one of the plurality of first switches from its output, thereby driving one of the plurality of heater resistors in a group.
Abstract:
The invention relates to an apparatus for providing information to a printer controller in order to identify the type of printer cartridge installed in a thermal ink jet printer. The apparatus includes a printer cable containing a set of electrically-conductive wires connected to contacts in a printer cable connector. The contacts of the printer cable connector make physical connection to an identification circuit on the printer cartridge. The identification circuit includes an electrical conductor which is at an electrical reference potential. When none, or one or more contacts on the cable connector are in electrical contact with the electrical conductor of the identification circuit, a signal corresponding to the identification of the printer cartridge is produced which is used by the printer controller to determine the type of printer cartridge installed in the printer. Selective contact between the connector contacts and the identification circuit, so as to produce an electrical code, may be obtained using a label having apertures, contact pads, electrical traces, or a combination thereof. Accordingly, various cartridge identification codes can be produced using various methods which allow encoding of the information on a cartridge during or after the manufacture of the cartridge body is substantially complete.