Seiko Epson Corporation

Norio Horaguchi

Toshikazu Kotaka

Kenjiro Murakami

Hiroshi Ishida

Shigeki Mizuno

Yoshiaki Nakayama

Motoyuki Niimura

Tatsumi Tsuboki

Hiroyuki Kato

Masahiro Kawajiri

Nobuhiro Inoue

Etsuo Okaue

Hiroyoshi Okada

Yoshihiko Kasai

Masaru Egawa

A level change point detection section detects a level change point, at which an output level switches, in a first position detection signal Ensgenerated by an encoder or a second position detection signal obtained by increasing the resolution of the Ens. Each time a predetermined number of level change points is detected, an energization timing determination section determines the timing, at which the predetermined number of level change points have been detected, to be an energization timing for the thermal head.

Printing apparatus and method of controlling printing apparatus

A control method of a media conveyance device enables accurately detecting media slack by a detection mechanism with multiple emitters and multiple photodetectors disposed opposite the emitters. A printer (media conveyance device) has a controller that controls a delivery mechanism, a conveyance mechanism that conveys media, a delivery mechanism, and a conveyance mechanism, and controls conveying roll paper; a first detector including a first emitter and first photodetector; and a second detector including a second emitter and second photodetector. When driving the conveyance mechanism, the controller selectively controls the first emitter and first photodetector to emit, and drives a spindle based on signal output from the first detector when first emitter emits, and signal output from the second detector when second emitter emits.

Media conveyance device, printer, and control method of a media conveyance device

A printerhas a movable memberthat can move following change in the tension on recording paperbetween a roll paper compartmentand a conveyance mechanismon the paper conveyance path. When recording paperof which the end is glued to the coreof a paper rollruns out, the tension on the recording paperrises and the movable membergoes to a tension-side error determination range Ein its range of allowable movement E. When the movable memberis in the tension-side error determination range E, the time the movable memberremains in the tension-side error determination range Eis counted, and if this measured time exceeds an error determination time, an error detection unitdetects an error. No-paper errors can therefore be detected without using a dedicated sensor.

Media conveyance control method and printer

An inkjet printer has a mechanism to counter change in the tension of the recording medium to convey the recording medium with more precision. Such printer has a media conveyance mechanism that conveys a recording medium; an inkjet printhead that prints on the conveyed medium when the printhead is located at a position opposed to the media conveyance mechanism; a media supply mechanism that supplies the medium to the media conveyance mechanism; a lever that is positioned between the media conveyance and media supply mechanisms and that moves to compensate and thus counter internal tension changes in the recording medium resulting from operation of these mechanisms; a detector that detects the movement or position of the lever; and a control unit that controls the media supply operation based on output from the detector so that the lever is urged back to or maintained in a home position.

Printer with mechanism for controlling recording medium tension

A conveyance device including an upstream roller that supplies a sheet medium to be processed to a conveyance path; a downstream roller that conveys the supplied medium to a processing position; and a control unit that, in order to convey the sheet medium at a constant speed, controls driving the upstream roller and the downstream roller using the constant speed as a target speed. The control unit changes the target speed of the upstream roller to eliminate a conveyance difference, which is the difference between the length of media conveyed by the upstream roller and the length of media conveyed by the downstream roller from the start of the conveyance operation, based on the conveyance difference in each conveyance operation.

Conveyance device, printing device, and conveyance method

A inkjet printer has a mechanism to counter change in the tension of the recording medium to convey the recording medium with more precision. In a method, the position or movement of a movable member is detected by a detector, and the recording medium is conveyed based on output from the detector so that the movable member is maintained in or urged back to a set position. Also, one or more operations are stopped when the movable member moves outside of an allowable movement range. Which operation(s) is or are stopped depends on whether the movable member moves outside its allowable range in a direction that increases or decreases the tension in the recording medium.

A printerhas a belt conveyor mechanismdisposed to a platen unitopposite a printhead. The belt conveyor mechanismhas three conveyor beltsmounted on a belt drive rollerand guide rollersto. The conveyor beltcurves in a C-shape when seen from outside the belt path where the conveyor belttravels around a guide roller. Another guide rolleris positioned outside of the belt path, and contacts the surface (conveyance surface) of the conveyor beltcurved in the C-shape. An encoderand inertia memberA are attached to the rotational shaftof the guide roller. Another inertia memberB is attached to the output shaftof the conveyor motor

Belt conveyance device, media conveyance device, and printer

When conveyance of the recording paperby the conveyance mechanismstops, the printersupplies power of a specific current level to the supply motor. This applies specific torque to the paper rollin the opposite direction as the direction in which tension is applied to the recording paperby a spring, and holds the movable memberat the same position as when conveyance of the recording paperstopped. The torque applied to the paper rollto hold the print position of the movable memberis torque sufficient to hold the paper rollstill without rolling, and is less than the torque required to turn the paper rollto maintain constant tension on the recording paper. Little current is therefore supplied to the supply motor, and the supply motoris prevented from overheating.

A printer has a mechanism to counter change in the tension of the recording medium to convey the recording medium with more precision. Such printer has a media conveyance mechanism that conveys a recording medium; a printhead that prints on the medium; a media supply mechanism that supplies the medium to the media conveyance mechanism; a movable member that can move to compensate and thus counter internal tension changes in the recording medium resulting from operation of the media conveyance and supply mechanisms; a detector that detects the movement or position of the movable member; and a control unit that controls the media supply operation based on output from the detector so that the movable member is urged back to or maintained in a home position.

A conveyance device including a drive roller that feeds a sheet medium from a media roll having the sheet medium wound in a roll that can rotate on a center axis of the roll, a drive roller that supplies the sheet medium from the media roll, a roll rotating unit that rotates the media roll and rewinds the supplied sheet medium, and first and second brake devices that apply a load to rotation of the media roll and are disposed to the roll rotating unit, wherein the first brake device is controlled to apply the load when not energized.

A printer wherein a drive roller of a pair of sheet discharge rollers is made of rubber and a driven roller of the pair of sheet discharge rollers is made of synthetic resin; the leading end of a sheet is guided so as to be abutted against the drive roller earlier than the driven roller; the sheet that is in the course of being discharged is guided by a sheet discharge tray so as to come in slidable contact with an edge portion that is on a print head side of a sheet discharge opening. As a result, the printer can provide satisfactory printing conditions quickly with a simple structure and reduce noise leaking from the sheet discharge opening.

Printer

Printer having noise noise reduction structure

Electronic sunglasses of the transmittance-varying type including liquid crystal panels employing the electro-optical effect and a solar cell used as a power source. The electronic sunglasses include a voltage detecting circuit having such a hysteresis characteristic so as to output a signal for changing transmittance of the liquid crystal panel from a high mode to a low mode at at least high predetermined voltage or illumination, and changing transmittance from a low mode to a high mode at at least a low voltage or illumination. The sunglasses also include a first switch which operates at at least two switch positions, one switch position having a first stage of illumination at less than 20,000 Lux and a second stage of illumination at 20,000 Lux or greater at which transmittance is changed from a high mode and another switch position disabling the voltage detecting circuit. Also included is a second switch which operates to change transmittance from a high mode to a low mode independently of the set voltage value in the voltage detecting circuit according to the hysteresis effect.

Growing community of inventors

Kamiina-gun, Japan

Norio Horaguchi