Abstract: An optical serial data bus for connecting logic cards used in a data processing system. The bus uses semiconductor lasers and PIN diodes as transmitters and receivers, transmitting through free space without the use of lenses or other optical elements. Each logic card communicates only with the adjacent cards on either side to minimize the transmission distance.

Abstract: A plugable interposer assembly for enclosing printed circuit cards used in electronic devices and accommodating the connection of cables and additional printed circuit card enclosures. The enclosure is completely shielded and is particularly adapted to use in circumstances where unskilled persons either plug or unplug the assembly into a backplane assembly.

Abstract: A pluggable assembly for enclosing printed circuit cards used in electronic devices. The enclosure is completely shielded and is particularly adapted to use in circumstances where unskilled persons either plug or unplug the assembly into a backplane assembly.

Abstract: A method for forming a master mold for optical storage disks includes thermally growing an oxide or nitride layer on a semiconductor wafer. The thermally grown layer is then coated with a photoresist. The photoresist is exposed to a laser beam to form a data pattern and developed. The oxide or nitride under the developed pattern is etched and the photoresist stripped to provide a semiconductor master mold for optical disks.

Abstract: A mechanical lock which serves to hold a transducer carriage in a fixed position at all times except when the storage disk is rotating at a speed sufficient to ensure that the transducers are flying at a height sufficient to avoid damage to the disk surface. The lock is disengaged by means of a solenoid and armature.

Abstract: Control information for a flexible magnetic disk storage assembly is recorded on the periphery of the disk in a region not used for recording data. The control information is read through the protective cover or envelope which encloses the disk by means of a magnetic transducer such as a four track audio cassette head which bears against the envelope. By recording index and sector pulses as part of the control information, hard sectoring can be inexpensively and accurately achieved. A recorded fixed frequency control signal can be read and used as part of the feedback loop in a phase locked oscillator used to control a d.c. motor driving the spindle. The control information can also include servo tracks which assist in registering the data transducer directly over data tracks on media which has changed its dimensions.

Abstract: This circuit system accommodates the interconnection of a plurality of modules, each containing a plurality of semiconductor chips, by means of a flexible printed circuit wiring assembly containing contact pads and an interconnection wiring pattern. The modules contain a set of contact pads corresponding to the pads on the flexible wiring assembly and alignment pins to bring the abutting pads into registration. The pads on the flexible wiring assembly have a plurality of contact bumps to make better contact with the module packs. Clamping means is provided to retain the module and exert pressure on the contact pads.

Abstract: A print ribbon driving mechanism including a switching bail swingingly mounted on a reciprocatively mounted support movable between two opposite spindles carrying print ribbon spools. The spindles have ratchet teeth, and the switching bail has a pair of opposite pawl surfaces for engaging the ratchet teeth as the support and bail are moved in opposite directions. A trigger lever is provided on each of the spindles which is responsive to the existence of ribbon on the associated spools so that the trigger lever drops into an operative position on depletion of the ribbon from the associated spool, and the switching bail is provided with two opposite camming surfaces adapted to engage the trigger levers in their operative dropped positions for swinging the switching bail into a position to engage the ratchet teeth of the spindle of the dropped trigger lever so as to wind ribbon onto this particular spool.

Abstract: A clothespin-like gripper having a pair of clamp jaw portions resiliently urged together and adapted to embrace and thereby grip a magnetic diskette or disk-jacket assembly for pulling the diskette from an original position into a final position. A swingable blocker is provided on the gripper so that the diskette is thereby blocked from being embraced by the gripper whereby the gripper may be used to move the diskette back from its final position into its original position without any embracing action by the gripper.