International Business Machines Corporation

Joseph T Wilson, Iii

Donald F Manning

Normand C Smith

John E Drejza

Bruce Allen Wolfe

Jeffrey V Gatto

James Calvin Walsh

A re-inker mechanism is described for replenishing ink in a ribbon by increasing the contact force between an ink supply roller and a transfer roller as the weight of the ink supply roller decreases. This is accomplished by locating the transfer roller rotatably in a fixed position and locating the ink supply roller somewhat beneath the transfer roller on a support that is movable. A biasing force is attached to the ink supply roller to urge the ink supply roller against the transfer roller with a force sufficient to overcome the weight of the ink supply roller and to provide a predetermined contact force between the ink supply roller and the transfer roller, so that as the ink is used, the weight of the ink supply roller decreases and the contact force with the transfer roller increases.

Ribbon re-inking mechanism

A tractor mechanism has an endless pin belt entrained around spaced drive and idler sprockets mounted between a pair of frame members. The idler sprocket is supported by a carrier movable longitudinally by springs to apply tension to the belt. The edges of the belt overhang gear teeth of the belt and are prevented from contact with the frame members by the gear teeth engaging an endless vertical wall on one of the frame members. The frame members and sprocket carrier are molded polycarbonate with carbon fiber and solid lubricant fillers to reduce electrostatic charge buildup and wear of the belt. The frame members are bolted together to clamp the sprocket carrier in place to maintain the belt tension applied by the springs. The sprocket carrier and frame members have aligned elongate openings for receiving a tractor guide shaft with a concentric plastic tube, the latter being attached to a retainer plate held loosely between the sprocket carrier and a frame member.

Forms feed tractor for a printer

A feed mechanism for transporting paper has an endless band with transport pins for insertion into the perforations in circular perforations in the paper. The feed pins are part of drive elements attached through perforations in an endless flexible band to gear teeth which are engaged by grooves in a drive pulley. The transport pins have a cap portion on top of a base portion. The cap portion is tapered in the shape of a circular involute and extends from the top of the truncated circular conical base portion. The perforations in the band have the shape of an ellipse with the major axis thereof aligned in the direction of movement of the band. The band can be either thin flexible steel or polymer and the pin portion and gear portion of the drive elements can be integral and molded from an elastomer material through the elliptical perforations in the band.

Pin belt for movement of perforated strip

A tractor feed mechanism for feeding print forms comprises a continuous flexible pin belt wrapped around a pair of drive pulleys rotatably supported by a tractor body. Pins projecting from the flexible belt engage the forms via perforation in the forms. A door pivotally connected to the tractor body and is rotatable between an open condition in which paper can be placed on or removed from the pins and a closed position in which the forms can be restrained from becoming disengaged from the pins during feeding by the pin belt. A cam rotatable with the door and a spring is operable therewith produce a first restraining force on the door in its closed position which allows the door to be lifted a predetermined amount by the forms during feeding by the pin belt to accommodate variations in the thickness of the forms caused by buckling or folds. The cam and spring produce a second restraining force while the door is in the closed position of a magnitude which prevents lifting of the door beyond the predetermined amount. The cam is structured such that the first restraining force produced by the spring means remains substantially constant up to the point where the door is lifted said predetermined amount.

Anti-flutter tractor door

Apparatus for adjustably positioning a supported transducer in sensing relation with recorded indicia on a shaft encoder in which a first frame portion is fixed and a second movable portion carrying the transducer is attached to the frame portion through a flexure means with the flexure means being on the opposite side of the shaft from the transducer and the movement of the transducer and path of indicia being at the same radius from the center of said shaft substantially decreasing the number of components formerly used, which enables highly accurate adjustments and lends itself to fabrication by molding.

Transducer adjustment apparatus for shaft encoder

A tractor for feeding perforated paper has an endless belt of flexible material having pins and teeth extending in opposite directions from said belt. The belt has more rigid sections corresponding to the locations of the teeth between flexible web sections. A pulley is provided which has curved sections and grooves for receiving the teeth of the belt. The curved sections comprise an arc with ends having points of tangency with planes of straight sections of the belt extending across the grooves. The curved sections may comprise a composite arc having end arc sections with points of tangency with the planes of the straight sections of the belt and a center arc section having points of tangency with the end arc sections. The curved sections may also be an arc which has a continuously increasing radius of curvature from the points of tangency with the planes of the straight sections of the belt to a center line between the grooves.

Pulley for forms feed tractor

A feed mechanism for a printer having a door with hinge elements connected by hinge pins to the tractor body so as to be rotatable between first and second position. The hinge elements have rotary cams with convex and planar surfaces. A single flat steel spring is simply supported between its ends by a platform. The spring is held in flexed condition in a continuous bend by the platform and the cams of the hinge elements. The platform has coplanar support edges for simply supporting the spring. Alignment and centering means on the platform maintain the horizontal axis of the spring aligned with the common axis of the hinge pins and centered between the cams.

Door and spring assembly for a paper feed mechanism

Apparatus for moving a print heat of a serial matrix printer into or out of contact with a recording medium in which the required motion is achieved during translation of the print head along the print line by a cam and follower and in which the contact pressure of the print heat is resiliently maintained.

Print head actuator

Position identifying transducer using a pair of serially connected magnetoresistive elements with an output terminal at their juncture and which lie in a common plane with the flux-sensitive areas of each element symmetrically disposed about a common center line that is transverse to the direction of motion of the transducer through a variable flux field. This arrangement permits identification of specific locations by providing a peak signal at a predetermined location regardless of the direction of relative motion between the transducer and flux field.

Magnetoresistive position transducer with invariable peak signal

Recording arrangement in which a row of ink jet nozzles is inclined with respect to the relative motion of a recording surface to permit the variously and selectively charged drops from each nozzle to be deflected by a single pair of planar electrostatic deflection plates common to all nozzles and parallel to the row so that each nozzle is capable of producing marks at regularly spaced locations along a plurality of parallel rows. Also disclosed is a method of determining the angle of inclination. The inclination angle, nozzle spacing, and deflection levels are preferably chosen so that marks can be placed at all possible data points by a single row of nozzles in a single recording pass. The disclosed method also provides for recording in either direction, the use of two or more parallel nozzle rows, and for the interlacing of drop marks at the recording surface.

Arrangement for multi-orifice ink jet print head

Method of improving mark alignment by causing substantially simultaneous impact on a recording medium of drops issuing as a series from an ink jet nozzle moving relative to the recording medium, by successively decreasing the deflection of each drop in the series and positioning the nozzle with respect to the recording surface to alter the respective path lengths of the drops such that the first and last drops of the series reach the recording member at approximately the same time.

Growing community of inventors

Endicott, NY, United States of America

Joseph T Wilson, Iii