Abstract: A uni-directionally rotated clutched driving gear having arcuate segments of gear teeth acts sequentially on two idler gears to effect a two-speed bi-directional rotation of a driven gear. The driven gear may be attached to the drive shaft of the character wheels in a recording calculator.

Abstract: An error correction system for a typewriter in which a silent type action with a blank type face is operatively connected and synchronized to initiate a backspace action and elevate and feed an error correction ribbon in advance of the striking of the blank type face against the space wherein an error was printed. Thus, to obliterate an error and type in a correct character, an operator need only perform two operations; depress the error key and the correct character key. Further, in accordance with the invention, the error key may be further depressed to a repeat position whereby a series of characters may be obliterated automatically.

Abstract: An improved printing ribbon for use between a writing electrode and a permeable counterelectrode across which a pulse of predetermined magnitude and duration is applied. The material of the ribbon is such that it experiences multiple electric breakdowns causing it to be propelled through the permeable counterelectrode onto a record sheet held adjacent the permeable counterelectrode outside the sandwich. In a preferred embodiment, the ribbon is provided with a metallized coating which serves as the permeable counterelectrode.

Abstract: A typewriter mechanism responsive to an operator-controlled key automatically inserts a sheet of paper between the platen and paper bail in preparation for printing by raising the bail as the platen-entrained paper advances with the platen and then restoring the bail when the paper has passed between the platen and the bail.

Abstract: A single-element type carrier printing mechanism is provided with an element movable to block tangential deflection of the type carrier at printing impact with the platen, is normally disengaged from frictional contact with the type carrier during rotational positioning of the type carrier. The deflection blocking element includes a blocking arm pivotally mounted for free rotation relative to the type carrier, provided with an abutment adapted to act against a blocking surface formed on the type carrier. The blocking arm is also provided with teeth for detent engagement with a tilt detent device which moves the blocking arm from its normally disengaged position into engagement with the blocking surface to prevent impact deflection.

Abstract: Disclosed herein is a thermoelectric printing method and apparatus pertaining to the technology which avoids the mechanical impact of printing elements upon an ink ribbon, as used in office machines or the like. In accordance with the method, an electrically insulating support of substantially two-dimensional perforated sheet material having two major surfaces, preferably glass fiber or nylon mesh material, is impregnated, in accordance with one embodiment, with electrically conductive printing ink, and, in accordance with another embodiment, with conductive ink in the form of pigment particles suspended in a dielectric binder. Then, by applying potential gradients or character signals across electrodes, sandwiching the support, one of which is permeable, ink is caused to transfer through the permeable electrode to paper or other recording material located outside the sandwich adjacent the permeable electrode.

Abstract: A single element type carrier having type characters with different printing areas is impacted against a recording medium with different impact intensities substantially corresponding to the different printing areas to effect uniform printing. The type carrier is driven in a printing movement by a resiliently biased member which imparts an impacting force to the type carrier as the member moves along a path in response to the rotational movement of a cam. To control the impacting force imparted to the type carrier, one of a plurality of stop abutments is selectively positionable in the path of the resiliently biased member to control the length of movement along the path during which the member imparts an impacting force to the type carrier.

Abstract: A pilgrim step indexing mechanism provided with oppositely facing toothed ratchet wheels of the same pitch is associated with a single indexing pawl and an associated detent spring which not only detentably holds the ratchet wheels but also biases the indexing pawl to engage the ratchet wheels. The indexing pawl has two teeth one of which engages one of the ratchet wheels during a reverse stroke of the pawl to reverse feed both ratchets one increment and during a forward stroke of the pawl to advance both ratchets two increments. The ratchet wheels may be connected with a platen of a printer whereby a line of printwork, after printing, will be positioned two line spaces above the printing line for easy viewing.

Abstract: A device for installing an inking ribbon in the ribbon fork of a typing machine comprising a housing having spool locating means for receiving and locating a ribbon pay-off and take-up spool, a guide in the housing for cooperating with locating means on the typing machine for locating the said spools in their correct positions on the typing machine when the device is installed in position thereon, the housing having guide surfaces for folding the ribbon on its path from the pay-off spool to the take-up spool so that a portion of the ribbon is folded in such a manner that it can be introduced into guide hooks on the ribbon fork on the typing machine when the device is in position therein without the need for the installer to manually feed the ribbon through the ribbon fork.

Abstract: An intermittent drive for a single-element printing typewriter, calculator or similar machine. The drive comprises a drive shaft couplable via a cycle clutch to a driven shaft and a governor disposed on the driven shaft to couple it with and maintain it at the same speed as the drive shaft during the clutch cycle. The governor comprises a friction wheel having a generally circular cross-section provided with flattened portions. During the clutch cycle, when the clutch engages the driven shaft, the friction wheel contacts a roll fixed to the drive shaft preventing the driven shaft from leading the drive shaft in response to reflected forces. At the end of the clutch cycle, when the clutch is disengaged, the friction wheel has rotated so that a flattened portion of the friction wheel faces the roll, and driven shaft is free from the rotation of the drive shaft.

Abstract: A matrix printing head for use in a thermoelectric printing process has a plurality of electrical conductors which are fixed in predetermined relationship to one another. The conductors are disposed in a plurality of plates, and the plates are fixed in predetermined relationship to each other to form a matrix of electrical conductors. The plates may be made of an electrically conductive material and have insulating slots cut completely through the plates to form the conductors. The plates are then stacked, sandwich fashion, with a layer of insulating material between each plate. The plates and layers may be pinned to insure accurate alignment, and an adhesive is applied to the surfaces of the plates and insulating layers. The stack is then compressed and the ends of the conductors are exposed to provide a printing surface at one end and leads for the electrical connection of means to activate selected conductors at the other end.