A linear encoder for numeric-control machine tools is provided that includes: a substantially rectilinear section-bar, which is adapted to be fixed on the structure of the machine tool; a substantially rectilinear scale strip, which is fixed on the section-bar so as to extend along the section-bar parallel to the section-bar longitudinal axis; a movable slider which is fitted/mounted on the section-bar so as to be able to move along the section-bar parallel to the section-bar longitudinal axis and skimming the scale strip, and which is adapted to be rigidly fixed to the movable piece of the machine tool; an electronic reading apparatus which is at least partially placed aboard the movable slider and is adapted to read the position of the movable slider on the scale strip; and a thermal-stabilization device which is adapted to bring and maintain substantially the whole scale strip stably at a predetermined target temperature.

A rotary encoder includes a rotor and a stator. The rotor and the stator are arranged in the rotary encoder such that, when the rotary encoder is arranged on a machine that includes a shaft having a rotation axis, a rotation of the rotor in relation to the stator about the rotation axis of the shaft is allowed, a relative movement between the rotor and the stator along the rotation axis of the shaft is restricted to a predetermined distance, and a movement of the rotor in relation to the shaft along the rotation axis of the shaft is allowed. Additionally, movement of the stator in relation to the machine along the rotation axis of the shaft may be allowed.

A rotary encoder includes a stator and a shaft having a bearing configuration arranged in a housing. The shaft is rotatable relative to the housing via the bearing arrangement, and a rotor is attached to the shaft. A strain sensor arrangement, attached to the housing, is adapted to determine a malfunction of the bearing configuration. The housing has a flexible structure that facilitates transmitting forces associated with the bearing configuration to the strain sensor arrangement. The strain sensor arrangement is adapted to detect tension and/or compression associated with the housing, and a malfunction of the bearing configuration is determined based on the detected tension and/or compression.

The invention relates to a rotary encoder (10) for a machine, in particular a hoist, crane or the like, and to a method for operating a rotary encoder, the rotary encoder having a rotary encoder shaft (12) which is connectable to a shaft of a machine for detecting a rotation of the shaft, the rotary encoder having a frame (11) which is mountable on a machine, the frame (11) having an encoder element (13) disposed thereon for detecting a rotation of the rotary encoder shaft and a signal output element (14) for outputting a rotation angle signal and/or a speed signal, the rotary encoder having a bearing device (20) by means of which the rotary encoder shaft is rotatably mounted on the frame, the rotary encoder having an insulating device (19) which electrically insulates the rotary encoder shaft and the bearing device from the frame.

A method for mounting a sensor bearing unit providing a bearing and an impulse ring provided with a target holder and with a target mounted on an axial portion of the target holder. The method including measuring an eccentricity E.sub.1 between the target and the axial portion of the target holder, measuring an eccentricity E.sub.2 between a groove made in the bore of an inner ring of the bearing and the bore, introducing the target holder inside the groove, turning the target holder inside the groove to an angular position in which the eccentricity E.sub.total between the target and the bore of the inner ring is less than or equal to a predetermined value which is lower than the sum of the eccentricities E.sub.1 and E.sub.2, and securing the target holder inside the groove of the inner ring at the angular position.

A rotor of a rotary electric machine includes a magnet that is a ring member arranged coaxially with a rotor core and assembled to an axial end part of the rotor core. The magnet is used for sensing a rotational angle of the rotor. The rotor core includes only one pair of core-side positioning portions which are arranged to be point-symmetric about a rotational axis. The magnet includes only one pair of magnet-side positioning portions which are arranged to be point-symmetric about the rotational axis. The magnet-side positioning portions are engaged with the core-side positioning portions, respectively, to position the magnet relative to the rotor core in a first direction, a second direction and a circumferential direction, and the magnet-side positioning portions are used as both a magnetization reference and an assembly reference.

A magnetic angular position sensor system is described herein, which includes a shaft rotatable around a rotation axis, the shaft having a soft magnetic shaft end portion. The system further includes a sensor chip spaced apart from the shaft end portion in an axial direction and defining a sensor plane, which is substantially perpendicular to the rotation axis. At least four magnetic field sensor elements are integrated in the sensor chip, with two of the magnetic field sensor elements being spaced apart from each other and are sensitive to magnetic field components in a first direction and wherein two of the magnetic field sensor elements are spaced apart from each other and are only sensitive to magnetic field components in a second direction, whereby the first and the second direction are mutually non-parallel and the first and the second direction being perpendicular to the rotation axis.

An electric discharge machine is provided. The electric discharge machine includes: an axis drive part moving a tool electrode in at least one axial direction; and a sensor unit detecting a linear movement position of the axis drive part in the axial direction. The sensor unit includes a measurement scale having a linear shape, a position detector scanning the measurement scale and obtaining position information, and a pair of adjustment blocks fixed to both ends of the measurement scale or the position detector and erected perpendicular to an extension direction of the measurement scale. The adjustment blocks are fixed to the axis drive part and are curved in the axial direction due to a temperature change.

A scanning unit for determining a relative angular position of an angular scale that is rotatable about an axis relative to the scanning unit includes a circuit board having a first surface and a second surface and evaluation electronics. A detector assembly is disposed in a manner that enables scanning of the angular scale located opposite the first surface of the circuit board. A housing body includes: slots extending circumferentially about the axis; lands in each case extending axially between two of the slots such that the housing body is axially flexible but torsionally and radially rigid; and a bottom disposed axially between the slots and the circuit board.

A position-measuring device includes a housing having a first portion in the form of a hollow section and extending in a longitudinal direction. The housing includes at least a first passage and a second passage, the first and second passages each extending in the longitudinal direction at least partially through the first portion. A scale is disposed within the housing for being scanned as part of a position measurement. The position-measuring device includes a connecting channel, the first and second passages being interconnected via the connecting channel.