ENCODERS. Presented by Jianguo (Max) Wang October 4, 2004. Concepts related to encoders. What is a sensor? A sensor is a device that detects the state of the environment such as energy, heat, light, magnet, supersonic, etc. and convert them to electric signals.
Jianguo (Max) Wang
October 4, 2004
A sensor is a device that detects the state of the environment such as energy, heat, light, magnet, supersonic, etc. and convert them to electric signals.
An encoder is a sensor for converting rotary motion or position to a series of electronic pulses
Linear encoders, which consist of a long linear read track (analogous to the code disk of a rotary encoder), together with a compact read head, address these concerns. We offer three grades of linear encoders, to suit a variety of application requirements.
Rotary encoders serve as measuring sensors for rotary motion and for linear motion when used in conjunction with mechanical measuring standards such as leadscrews, and convert rotary motion(incremental or absolute) into electrical signals. They are both effective and low cost feedback devices. In high-accuracy applications, a number of error sources (leadscrew cumulative and periodic error, thermal expansion, and nut backlash, for example)
render rotary feedback inadequate.
• Absolute encoders have a unique code that can be detected for each angular position
• Absolute encoders are much more complex and expensive than incremental encoders
• Pulses from LEDS are counted to provide rotary position
• Two detectors are used to determine direction (quadrature)
• Index pulse used to denote start point
• Otherwise pulses are not unique
While a lead screw or rack-and-pinion converts rotary motion to linear motion, an encoder converts the same motion into electronic pulses. The pulses typically are used as input signals for counters, PLCs, or numerical-control equipment
Roll or sheet materials need to be measured during transport through converting or cut-to-length machinery. An encoder, when combined with a measuring wheel or coupled to a roller, will produce electronic pulses equal to units of length. Since fractional units may be measured, very precise operation is possible
Encoders are wildly used in industry
From less than 100$ to more than 10,000 $. It depends on your requirement.
Linear encoders are more accurate.
Absolute encoders are more expensive.
Incremental encoders spend more time for startup
Model 716 (Cube Encoder) made by ECP were equipped on the lumber devices to produce up to 15% more lumber from each log
The Company of Ground Force mounts EPC encoder on the trucks used at mining operationsto measure the rotation of pump shafts and of augers. The pumps deliver wet ingredients, while the augers deliver the dry ingredients.