Abstract: For use with a matrix printer, a method for printing dot columns at uniform spacing regardless of irregular print carrier motion, the column spacing selected, and the use of a low resolution pulse source. The pulse source generates control pulses at intervals representing carrier movement through a given distance greater than any selected dot column spacing. As disclosed the method calculates the distances from a control pulse to the possible printing positions between two control pulses, according to the column spacing selected, and the known distance between pulses. Also, the time between control pulses is measured and used with the known distance between pulses to calculate the carrier velocity. From the carrier velocity and the distance from a control pulse to printing positions between control pulses, the times of energization of the print wires to effect printing at the uniformly spaced printing positions are calculated.

Abstract: A printer having a carriage guided for movement along a platen and supporting a wire matrix printing element includes means for changing the distance between the printing element and the platen an amount to facilitate paper feeding and an additional amount for paper insertion.The means of changing the distance between printing element and platen includes an electric motor driven in accordance with a stored program which determines motor acceleration characteristics.

Abstract: Disclosed is a mechanism so arranged that a relatively weak power source can be employed to effect error ribbon elevation and incremental feed. A bridge which is pivotably mounted on a frame carries a rotatably mounted ratchet and a pivotably mounted pawl which, when the bridge is rotated by a magnet to elevate the bridge, is caused to react with a frame part and pivot relative to and to drive the ratchet to feed ribbon.

Abstract: A ribbon feed and elevating mechanism is so constructed that active parts for incrementally feeding and for elevating a ribbon from a rest position into one or more working positions form one structural unit mounted on a common shaft thereby providing a compact, easy to assemble unit for association with a typewriter of the type having a print element supported on a movable carriage. Due to the interaction of a lifting lever with a control lever and a pivoting lever to which a ribbon guide is linked, it is possible in a simple manner to raise the ribbon alternately into two different reproduction levels. A rocker, arm also mounted on the common shaft, serves to establish the increment of feed by which ribbon is to be advanced.

Abstract: An error correcting typewriter having separate elevating and feed mechanism for carbon and error correction ribbons includes a common cyclic motive source operable in response to type commands to drive a cam shaft which is axially shiftable by means of an electromagnet energized by a correction signal. Normally, the cam shaft is positioned in engagement with a carbon ribbon drive lever and out of engagement with an error correction ribbon drive lever. A shift of the cam shaft disengages it from the carbon ribbon drive lever and engages it with the error correction ribbon drive lever. The carbon ribbon drive lever simultaneously operates a carbon ribbon elevating mechanism and a feed mechanism. Energization of the electromagnet operates a lever which directly operates the correction ribbon feed mechanism and simultaneously shifts the cam shaft to engage it with the error correction ribbon drive lever which when driven is operative on the correction ribbon elevating mechanism.

Abstract: The invention is a mechanism for raising and lowering the ribbon in typewriters to make typed text visible. No separate drive such as a motor or magnet is required to raise the ribbon. The ribbon is raised by means of a spring-loaded bar prior to each character reproduction. To accomplish this, an armature of a control magnet releases a pivoting lever and the spring loaded bar. A pin wheel, driven by a motor and acting on the lever serves to return the bar and allow return of the ribbon. The motor is energized after each character reproduction to advance either a type element carrier or the paper carrier by one character space. In typewriters with ribbon spools fixed to the machine frame, the ribbon spool drive also can be derived from the spring powered bar.

Abstract: A line spacing mechanism having a platen, a line spacing ratchet, a line spacing lever mounting a pawl adapted to engage and to drive said ratchet upon pivoting movement of said line space lever, a setting lever for controlling the time of engagement of said pawl and ratchet and adjustable stop means for limiting driving movement of said pawl and overtravel of the platen. The mechanism includes a single detent means for detentably holding said ratchet, said setting lever and said stop means, and includes means on said setting lever operable on said detent means to release said ratchet for irregular movement.

Abstract: In a movable printing point typewriter wherein line feed mechanism on a stationary platen is driven by type element carrier drive mechanism, provision is made to detect the distance of the carrier from an established left margin and, if it is too short, to move the carrier first in escapement direction a sufficient distance from the left margin and then in carrier return direction so that a line feed can be completed before the carrier is returned to the left margin.

Abstract: A support for the paper carrier in typewriters or similar machines extends between a base frame and the paper carrier. The support not only has the function of interconnecting the base frame and the paper carrier but it also functions, due to the provision of a tool deformable slot, as an adjustable support whereby the platen mounted on the paper carrier can be adjusted both vertically and horizontally relative to a printing element.

Abstract: A pullout shelf provided with rollers is mounted on static roller guide structure having several tracks with openings in the tracks to allow manipulation of the shelf and a supported machine to desired heights and inclinations.

Abstract: A large format paper handling assembly has an axially stationary platen which is rotatably mounted on pivotally mounted support arms. The platen is supported on spaced frame supported front guide rollers and rear feed rollers. The off axis rear feed rollers are adapted to be manually and/or automatically line indexed to frictionally feed paper between the rear feed rollers and the platen. Hold down rollers are mounted on a bail extending between spaced paper feed release levers which are pivotally mounted on the frame about the axis of the front guide rollers and are movable away from the platen against the bias of springs. The springs acting through the hold down rollers maintain the platen in frictional engagement with its supporting front guide rollers and rear feed rollers. The pivotal movement of the paper feed release lever withdraws the hold down rollers and also acts to pivot the platen support arms to move the platen away from the front guide rollers and the rear feed rollers.

Abstract: Disclosed is a printing plane adjusting mechanism for a typewriter or similar machine wherein a paper handling system including a platen defining the printing plane is finely as well as coarsely adjustable by a single lever relative to a printing element to establish a predetermined normal distance between the printing plane and printing element or varied distances other than normal to accommodate paper packs of varying thickness. Adjustment of the normal distance or gap is effected without loosening or tightening screws.

Abstract: A crankshaft assembly for precision low load applications has cylindrical crankpins mounted on concave peripheral grooves on the ends of a crankshaft and coupled thereto by clamps which lockingly engage aligned annular grooves in the crankshaft and crankpin.

Abstract: A device to facilitate the changing of disc-shaped type carriers in typewriters or printers includes a lever operated device to push against the type disc and to press it off its shaft. A basket is provided to catch the type wheel after its disengagement from the shaft to prevent it from falling into the interior of the machine.

Abstract: A paper handling assembly supporting a platen, a paper bail adjustably mounted for movement relative to said platen and a paper guide trough adjustably mounted for movement relative to said platen. The assembly includes a common shaft which mounts a first paper pack thickness adjusting lever operative to rotate said shaft to effect movement of the entire paper handling assembly relative to a frame to adjust the printing gap, rotatably supports a second paper bail adjusting lever operative to adjustably move said paper bail, and rotatably supports a third paper trough adjusting lever operative to adjustably move said paper trough.

Abstract: To change a type disc without moving or removing a ribbon cartridge while yet permitting the location of a ribbon cartridge closer to the printing point of a type disc printer, there is provided mechanism to allow pivoting movement of a hammer assembly relative to an independently pivoted type disc drive assembly thereby to change their relative orientation, after which continued movement of the hammer assembly carries the pivotally mounted type disc drive assembly to a type disc change position. The change in orientation of the hammer assembly relative to the type disc drive assembly, before pivoting the type disc assembly, allows greater arcuate movement to type disc change position without interference between the hammer assembly and the ribbon cartridge.

Abstract: A daisy wheel typewriter wherein wheel positioning to present a character for printing and hammer actuation to effect printing of a selected character are electronically operated in response to keyboard generated signals. Functions associated with a printing action, e.g., ribbon lift, ribbon feed, and carriage spacing, are, however, operated mechanically in synchronism with the electronics by a timing disc driven by a print cycle function actuating shaft. Non-printing service functions are also operated mechanically by conventional powered mechanisms responsive to keyboard generated signals.