Abstract: A sheet paper feed apparatus for a typewriter having a frame supporting a platen for holding and providing at least longitudinal motion to a sheet of paper. A rectangular tray includes forward and rear paper supports for supporting a stack of paper thereon. Therebetween is a shinglar roll or wheel which supports the central portion of the paper stack is a slightly bowed configuration. The shinglar wheel is first driven in a rearward fashion to effect removal of the forward or leading edge of the bottom most sheet from the stack away from the forward support, and then the shinglar wheel rotation is reversed effecting feeding of the sheet of paper away from the bottom of the stack and below the forward paper support into paper feed rolls and ultimately onto the platen.

Abstract: An interactive ink jet printer prints characters of a language from left to right or right to left in accordance with the direction in which the language is normally written. The signals for the direction in which a motor, which moves ink droplet supply device relative to a recording medium, the signals from a grating, which indicates the direction of motion of the ink droplet supply device and its position relative to a reference position, and the signals for the location of the ink droplet supply device at the reference position are changed whenever the direction of character printing is to be reversed.

Abstract: In a typewriter environment, a carrier mounted sensor for calculating the width of a sheet of paper on the platen and for thereafter setting-up margins for that sheet of paper. In addition to supporting the sensor, the carrier supports the printhead and associated apparatus for detecting the position of the carrier relative to the platen at each escapement position of the carrier. The sensor starts its scan at the extreme left position of the carrier and senses the left edge of the paper at a transition from dark-(the platen surface) to-light (the sheet of paper). This transition point is detected and stored. The carrier continues its rightward scan and the right edge of the sheet of paper signals a transition from light-to-dark. This position is detected and stored. The carrier and sensor continue scanning to the right for a specific distance to eliminate errors that are caused by dark areas on the paper that prematurely trigger light-to-dark transitions.

Abstract: Disclosed is a digital escapement control system in which the motor (DC) control is completely digital requiring no tachometer generation of feed back signal nor any analog to digital convertors. Connected to the DC motor shaft is a code wheel and detector to determine the time between discreet positions of the motor shaft as it rotates. The time between discreet positions is then compared with a desired time, and the difference is stored, as by a register. The difference is then converted to a pulse-width-modulated (PWM) signal which directly controls the rotational velocity of the motor, increasing or decreasing it as necessary. The system operates, in a ramp, open loop start up mode and digital velocity controlled braking mode while in the motional mode with the feed back as described above. At start up, provision is made for inserting the feed back loop when the velocity reaches some predetermined level or percentage of the desired velocity.

Abstract: In a typewriter environment, a carrier mounted sensor for calculating the width of a sheet of paper on the platen and for thereafter setting-up proportional margins for that sheet of paper. In addition to supporting the sensor, the carrier supports the printhead and associated apparatus for detecting the position of the carrier relative to the platen at each escapement position of the carrier. The sensor starts its scan at the extreme left position of the carrier and senses the left edge of the paper at a transition from dark (the platen surface)-to-light (the sheet of paper). This transition point is detected and stored. The carrier continues its rightward scan and the right edge of the sheet of paper signals a transition from light-to-dark. This position is detected and stored. The carrier and sensor continue scanning to the right for a specific distance to eliminate errors that are caused by dark areas on the paper that prematurely trigger light-to-dark transitions.