A device for determines the torque and/or the rotary angle between a first shaft and a second shaft, which are coupled via a gear mechanism to rotate relative to one another about an axis of rotation. The first shaft has a first end region, a second end region, and a first direction vector pointing in parallel with the axis of rotation from the first end region to the second end region, and the second shaft has a first end region, a second end region, and a second direction vector pointing in parallel with the axis of rotation from the first end region to the second end region. The first shaft is designed as a hollow shaft and the second shaft is arranged coaxially in the first shaft in such a way that the first direction vector and the second direction vector have the same orientation.

Embodiments relate to a torsion sensor device which measures a degree of torsion of a measurement object by using a fiber Bragg gratings (FBG) sensor, the sensor device comprising: an FBG sensor including a sensing unit formed in one section of an elongated optical fiber; and a fixing device for fixing and supporting the FBG sensor to cause displacement of the FBG sensor according to motion of the measurement object, wherein the fixing device includes a bending prevention member to enable the sensing unit to have torsion displacement without bending displacement, according to the motion of the measurement object.

Embodiments relate to a torsion sensor device which measures a degree of torsion of a measurement object by using a fiber Bragg gratings (FBG) sensor, the sensor device comprising: an FBG sensor including a sensing unit formed in one section of an elongated optical fiber; and a fixing device for fixing and supporting the FBG sensor to cause displacement of the FBG sensor according to motion of the measurement object, wherein the fixing device includes a bending prevention member to enable the sensing unit to have torsion displacement without bending displacement, according to the motion of the measurement object.

Apparatus and methods for web tension control are provided. In an example, an apparatus can include a tension beam configured to deflect in a predictive manner when under a force load, a first shaft directly coupled to the tension beam and configured to mechanically interface with a torque device, a second shaft directly coupled to the tension beam opposite the first shaft and configured to interface with a structural member of a web machine, and a strain gauge coupled to the tension beam and configured to provide an electrical representation of the force load.

An optical sensor, an optical encoder, a torque detection apparatus, and an electric power steering apparatus less affected by fluctuations in the amount of detected light and with an improved resolution are provided. The optical sensor includes a first polarizing layer that splits incident light to light with a first polarization direction, a first photoreceiver that receives first polarized light split by the first polarizing layer, a second polarizing layer that splits the incident light to light with a second polarization direction, and a second photoreceiver that receives second polarized light split by the second polarizing layer. The first photoreceiver and the second photoreceiver are positioned alternatingly and spaced uniformly with each other.

An optical sensor, an optical encoder, a torque detection apparatus, and an electric power steering apparatus less affected by fluctuations in the amount of detected light and with an improved resolution are provided. The optical sensor includes a first polarizing layer that splits incident light to light with a first polarization direction, a first photoreceiver that receives first polarized light split by the first polarizing layer, a second polarizing layer that splits the incident light to light with a second polarization direction, and a second photoreceiver that receives second polarized light split by the second polarizing layer. The first photoreceiver and the second photoreceiver are positioned alternatingly and spaced uniformly with each other.

A method and a device for measuring the torque in the drivetrain (1) of a wind power plant is described, having at least two incremental encoders (7, 8) which are positioned at two different positions on at least one shaft (3) of the drivetrain (1) and which each supply periodic rotational signals, wherein the phases of the rotational signals are evaluated in order to detect a phase shift, and a torque of the shaft (1) is determined from the phase shift. The detected phase shift is corrected as a function of a zero load phase shift (A.sub.Zero), using a rigidity factor K, wherein, in order to determine the zero load phase shift (A.sub.Zero) and the rigidity factor K, in-situ calibration is carried out before and/or between the torque-determining processes. The in-situ calibration is performed at zero load of the wind power plant, i.e. below a rated rotational speed and with a generator torque equal to zero, and at the rated load of the wind power plant, i.e. at the rated rotational speed and with a generator torque greater than zero.

A component has an integrated sensor device for an optical, multi-axis measurement of a force applied to the component. The component includes a cavity and a first support element having one or more first optical elements and a second support element having one or more second optical elements. The first support element and the second support element are formed in the cavity and partially inserted into the component. A transmission device generates at least two beams in independent directions when connected to a power source. The beams pass through the cavity between the first optical elements and the second optical elements. The first optical elements and the second optical elements are adapted to generate information about a relative positional change of the first support element with respect to the second support element based on the at least two beams. The transmission device provides the information for measuring the force application.

A component has an integrated sensor device for an optical, multi-axis measurement of a force applied to the component. The component includes a cavity and a first support element having one or more first optical elements and a second support element having one or more second optical elements. The first support element and the second support element are formed in the cavity and partially inserted into the component. A transmission device generates at least two beams in independent directions when connected to a power source. The beams pass through the cavity between the first optical elements and the second optical elements. The first optical elements and the second optical elements are adapted to generate information about a relative positional change of the first support element with respect to the second support element based on the at least two beams. The transmission device provides the information for measuring the force application.

Systems and methods for measuring displacement parameters of rotating shafts and couplings are disclosed. In some aspects, a measurement system includes a shaft extended in a longitudinal direction and a target wheel configured to rotate with the shaft. The target wheel includes sensor targets circumferentially distributed around the target wheel. Some of the targets are slanted in the longitudinal direction and some of the targets are parallel to the longitudinal direction. The measurement system includes a sensor array including at least three sensors mounted radially around the shaft and configured to detect the sensor targets as the target wheel rotates with the shaft. The measurement system includes a controller configured to receive sensor signals from the sensors and determine, based on the sensor signals, at least an axial displacement measurement of the shaft in the longitudinal direction and a radial displacement measurement of the shaft.