Abstract: The determination of the position of a tape thread-in and thread-out mechanism in a cassette recorder is carried out using contact paths together with a slider contact that form position switches. Output signals of the position switches are coupled via a resistor network that combines the output signals and produces an output signal on a single conductor. The resistor network output signal is coupled to an input of an analog -to-digital converter. To improve the reliability of determining the position of the mechanism without requiring the use of highly accurate resistors in the resistor network, the voltage value assigned to each individual position is measured at the output of the network during a calibration operation. The voltage values are stored in a memory and used as the desired values during normal operation.

Abstract: A printing system includes print ribbon wound on first and second rotatable reels and a rotatable capstan for moving the ribbon between the first and second reels, such that ribbon is supplied from the first reel and is collected after use on the second reel. A microprocessor controls both the reel and capstan movements and computes the quantity of ribbon wound on each reel based on a known diameter of the capstan and the relationship between the number of rotational steps moved by the capstan and the number of rotational steps moved by the corresponding reel during a given time period. The microprocessor includes a random access memory in which a plurality of ramp tables are stored for controlling the movements of the reels. Each ramp table includes a speed parameter representing a particular rotational speed and an acceleration parameter representing a number of rotational steps for ramping up to and down from the particular speed, for a discrete range of ribbon diameters.

Abstract: A filament winding machine includes a servomotor connected to position a filament distributing carriage relative to a rotating mandrel to form a tubular member. An incremental encoder is connected to the mandrel and produces a pulse related output per mandrel revolution. An absolute encoder is connected to the servomotor and provides an absolute position number. The encoders are sampled at a fixed rate. A mathematical calculating circuit reads the incremental encoder and based on a predetermined movement design for the gear drive, the desired winding configuration and the like determines the proper position, which is compared to the absolute encoder reading to produce an error control signal to the servomotor. A preselected sequence of actual position numbers and the corresponding calculated position numbers are continuously updated in a temporary memory.

Abstract: A programming apparatus for use with a machine applying successive wraps of rubber on a tire surface during a retreading operation. The contour of the layers to be deposited is translated upon a template device by positioning of select metallic contacts. In turn, the number of wraps for a given arcuate distance are more finely defined upon a second template device. The second template being indexed with a series of metallic contacts. The entire operation is controlled electrically such that successive movement of the tire surface is correlated to arcuate distance.