Abstract: A paper transport device for a recorder such as an ink jet printer has a support for clean paper, guidance rollers, and a drive device. The transport devices moves the paper from the paper support past a printing head. In order to exert a symmetrical pull on the paper and simultaneously to make substantially the entire width of the paper available for writing thereon, the paper transport device has at least two rollers mounted on an axle rotated by the drive device, the rollers being disposed a distance from one another at right angles relative to the forward feed direction of the paper. The drive rollers are mounted on the axle so as to run freely on the axle in the direction of rotation of the axle, but lock when attempted to be rotated in the opposite direction so that skewed paper is easily and automatically aligned to move in a straight path. Each drive roller has an idler roller associated therewith.

Abstract: In an exemplary embodiment, the recording paper is transported by at least one drive capstan driven by a motor across a writing surface at which a fluid writer is disposed for writing. The object of the disclosure is to create a paper transport system which always avoids unnecessary contaminations due to writing fluid with certainty. This object is achieved in that the motor-driven drive capstan has a no-load indicator allocated to it which identifies no-load operation of the drive capstan and generates a shut-down signal for the fluid jet writer.

Abstract: In an exemplary embodiment, a recording unit comprises a support mount for the blank paper, rollers for the guidance and conveying of the paper, and a stylus which writes essentially perpendicularly to the longitudinal direction of the paper. The paper is conducted over a deflection roller. The deflection roller is swingably mounted so as to be angularly shiftable essentially in the longitudinal direction of the paper.

Abstract: A fluid-jet writing system in which writing fluid is pumped from a fluid container or reservoir to one or more fluid-jet writing nozzles. A valve is located in the hydraulic circuitry which connects the pump to the nozzles for controlling the flow of writing fluid to the nozzle. A comparator is also located in the hydraulic circuitry for maintaining a predetermined fluid pressure between the pump and the valve by controlling the operation of the pump.

Abstract: A pump mechanism for pumping ink or similar writing fluid from a fluid reservoir to a writing device. A piston is moved in a cylinder in one direction to draw ink into the cylinder from a reservoir through a capillary tube, and is moved in an opposite direction to discharge the ink to a writing device while at the same time, in cooperation with a flexible membrane located in the cylinder and connected to the piston, to discharge any air in the capillary tube back into the reservoir.

Abstract: A pump mechanism for delivering ink or the like writing fluid from a reservoir to a point of utilization such as a writing device. The mechanism includes a piston slidable in a cylinder for drawing ink into the cylinder during a suction stroke and discharging the ink during a pumping stroke. The cylinder is formed by a cylinder wall which includes a frusto-conical portion tapered inwardly in a direction away from the piston. The piston comprises a single plastic member having a forward end portion which faces and cooperates with the tapered portion of the cylinder wall and which has an outside diameter which is greater than the smallest diameter of the tapered cylinder wall portion, whereby the forward end portion of the piston engages the tapered cylinder wall portion as the piston moves forward during a pumping stroke.