Abstract: Marking apparatus is provided for carrying out the marking of programmed character strings upon brittle surfaces such as glass. The lines forming the characters are generated by a gas entrained stream of abrasive particles which are expressed from the opening of a nozzle located in close adjacency with the surface being marked. Switching of this abrasive particle string between marking and non-marking orientations is carried out by a diversionary flow of gas under pressure which is expressed into the stream at a rate effective to integrate with the abrasive particle and divert the marking stream away from a marking axis. A suction port is provided which removes particles subsequent to marking or having been diverted to a collection location. In one embodiment, the nozzle from which the marking particulate stream is expressed is maneuvered between lifted or retracted positions and marking positions in close adjacency with the surface being marked.

Abstract: Marking apparatus for moving a marking head to coordinate positions utilizing two fixed stepper motors performing in conjunction with a cable and pulley drive system. The dynamics of pneumatically driven marrker pins within marker heads are accommodated for by a topology which includes a marker support base which, in turn, is supported in force transfer relationship with an air bearing which rides over a fiat platen surface. Improved marker head structure is developed utilizing a polyetherimide material and a design providing the introduction of return air into a two-component piston chamber at a location above a seating surface.

Abstract: Marking apparatus and method is described wherein an array of marker pins are carried by translational assembly which, in turn, is driven from stepper motors which perform in conjunction with high helix lead angle lead screws. Solenoid actuated pneumatic valves are employed to actuate the marker pins within an array thereof and the entire assemblage of motors, valves, translational mechanism, and control features are retained within a compact housing structure. The control system and associated translational mechanism is capable of driving the marker head assembly in matrix, raster, and continuous modes of operation. Speed of marking is enhanced through the employment of a masking procedure wherein the translational mechanism drives the marker head assembly only to locations where active character forming pixels are present.