Systems are described for converting the angular position of a shaft or an axle of a rotary motor to an analog or a digital code indicative of the angular position. The systems may include a magnetic disk encoded with first magnetic transitions and second magnetic transitions, where the first magnetic transitions are on a first circumference of the magnetic disk, the second magnetic transitions are on a second circumference of the magnetic disk, the first magnetic transitions represent regions on the magnetic disk, and the second magnetic transitions represent locations on the magnetic disk within each of the regions. The systems may include a first sensor to detect a region based on the first magnetic transitions and a second sensor to detect a location based on the second magnetic transitions. The systems may also include a decoder to identify an absolute location on the magnetic disk based on the region detected by the first sensor and the location detected by the second sensor.

An encoder device including: a position detection unit for detecting position information of a moving part; a magnet having a plurality of polarities along a moving direction of the moving part; an electric signal generation unit for generating an electric signal, based on a magnetic characteristic of a magnetosensitive part, the electric signal generation unit having the magnetosensitive part whose magnetic characteristic is changed by a change in magnetic field associated with movement of the moving part and a first magnetic body for guiding magnetic flux lines of the magnet toward the magnetosensitive part; and a second magnetic body for guiding magnetic flux lines of a part having one polarity of the magnet toward a part having other polarity of the magnet, the second magnetic body being disposed between the magnet and the magnetosensitive part.

Systems are described for converting the angular position of a shaft or an axle of a rotary motor to an analog or a digital code indicative of the angular position. The systems may include a magnetic disk encoded with first magnetic transitions and second magnetic transitions, where the first magnetic transitions are on a first circumference of the magnetic disk, the second magnetic transitions are on a second circumference of the magnetic disk, the first magnetic transitions represent regions on the magnetic disk, and the second magnetic transitions represent locations on the magnetic disk within each of the regions. The systems may include a first sensor to detect a region based on the first magnetic transitions and a second sensor to detect a location based on the second magnetic transitions. The systems may also include a decoder to identify an absolute location on the magnetic disk based on the region detected by the first sensor and the location detected by the second sensor.

A power tool includes a motor having an output shaft, an extensible member driven by the motor, a working assembly movable in response to contact with a distal end of the extensible member, a first sensor configured to detect a home position of the extensible member, a second sensor configured to detect rotation of the motor output shaft, and a controller in electrical communication with the first and second sensors. The controller is configured to drive the motor output shaft in a first rotational direction a predetermined number of revolutions counted by the second sensor, thereby displacing the extensible member from the home position. The controller is also configured to drive the motor output shaft in an opposite, second rotational direction to thereby return the extensible member until the home position is detected by the first sensor.

A ring magnetic encoder includes a ring magnetic object and a ring code configured on the outside of the ring magnetic object. The ring magnetic object is divided into a first ring part and a second ring part. The ring code further includes a plurality of sector IDs, upper offset codes and lower offset codes. The sector IDs are configured on the outside of the ring magnetic object in fixed intervals. The upper offset codes and the lower offset codes are configured in the intervals respectively. The upper offset codes are configured on the first ring part, and the lower offset codes are configured on the second ring part. According to the upper offset codes and the lower offset codes, the offset of the rotary shaft during rotating can be detected for precisely positioning.

Systems are described for converting the angular position of a shaft or an axle of a rotary motor to an analog or a digital code indicative of the angular position. The systems may include a magnetic disk encoded with first magnetic transitions and second magnetic transitions, where the first magnetic transitions are on a first circumference of the magnetic disk, the second magnetic transitions are on a second circumference of the magnetic disk, the first magnetic transitions represent regions on the magnetic disk, and the second magnetic transitions represent locations on the magnetic disk within each of the regions. The systems may include a first sensor to detect a region based on the first magnetic transitions and a second sensor to detect a location based on the second magnetic transitions. The systems may also include a decoder to identify an absolute location on the magnetic disk based on the region detected by the first sensor and the location detected by the second sensor.

A magnetic encoder apparatus is presented that includes a plurality of magnetic sensor elements (e.g. Hall sensors) for reading an associated magnetic scale that produces a periodically repeating magnetic pattern. The plurality of magnetic sensor elements produce a plurality of sensor signals and an analyzer is provided for analyzing the plurality of sensor signals to provide a measure of the position of the magnetic sensor elements relative to the associated magnetic scale. The analyzer is arranged to use the plurality of sensor signals to assess the period of the periodically repeating magnetic pattern sensed by the plurality of magnetic sensor elements. In this manner, the requirement to carefully match the period of the sensor elements with the periodically repeating magnetic pattern of the associated magnetic scale is avoided.

The disclosure relates to an electromagnetic transport system and to a method for operating the system. The system comprises a stator and at least one mover which is movable with respect to the stator along a path. The system also comprises a first positioning system with sensors arranged on the stator, which interact with a first encoder track of the at least one mover to determine a position of the at least one mover. The system comprises a second positioning system in at least one zone of the system. That second positioning system comprises at least one sensor which is arranged in the at least one zone, wherein the sensor detects or scans a second encoder track attached to the at least one mover to determine the position of the at least one mover in the at least one zone with a higher accuracy than with the first positioning system.

Disclosed is an electronic scale ruler, having a scale ruler main body, a main control board, an input, a display screen, a light source, a vernier base, and a distance conversion assembly. The scale ruler main body has an outer edge side. The light source is mounted on the outer edge side of the scale ruler main body, having a plurality of light beads and being capable of displaying scale. The vernier base is removably mounted on the outer edge side of the scale ruler main body, being capable of moving along a length direction of the outer edge side of the scale ruler main body. The distance conversion assembly is configured to calculate a movement of the vernier base from an origin on the outer edge side of the scale ruler main body.