The Model RH encoder, also known as a Pulse Position Indicator (PPI), generates tracking pulses for web applications, and in particular for material handling sortation applications when used with bar code laser scanners or CCD vision systems. 12″ or 30cm circumference measuring wheels ride directly on the conveyor belt or web eliminating any slippage problems typically encountered with shaft encoders. With its double wheel construction, the encoder is self-aligning when allowed to pivot freely from its integral arm. The encoder’s weight is sufficient to maintain contact when mounted above the moving material. For mounting below the belt use MB-UB1 under belt mounting accessory.
Shaft rotation is converted into square wave output pulses to provide an accurate means of digitizing position, rate or direction of rotation. A shatter-proof optical disk attached to the encoder shaft interrupts an infrared light beam and photo sensor. Internal wave shaping circuitry provides a square wave output that is compatible with all popular counters and digital tachometers. When used with measuring wheels it can accurately measure inches, feet, centimeters, inches/min., feet/min., and many others.
Configurations consist of: unidirectional that produces a single output (output A) with the specified number of counts per revolution regardless of which direction the shaft is rotating; and quadrature that produces 2 outputs (A and B) for indicating amount and direction of shaft rotation. Both are also available with optional index output (output Z).
The Anti-Jitter option was designed for conveyor and web systems that require continuous and accurate measurement of the web’s movement even if the system must be stopped and restarted without reset. “Anti-Jitter eliminates the effects of mechanical vibration and the possible dither that results in false output pulses and the subsequent erroneous counts when the system is actually “stopped”. “Anti-jitter” is available on single output models with up to 60 counts per revolution.