A torsion balance is provided which includes a twisting wire and a reflector. The twisting wire is a suspended carbon nanotube. The reflector is hung on the twisting wire. The reflector further includes a film, a first reflecting layer, and a second reflecting layer; and the film includes a first surface and a second surface opposite to the first surface, and the first reflecting layer is located on the first surface and the second reflecting layer is located on the second surface.

A torque measuring device for measuring the torque in a shaft that is subjected to torsion and has two axially arranged shaft sections. A first shaft section functions as a driveshaft and a second shaft section functions as an output shaft and is connected to a load-dependent sensor. An annular light-sensitive element is attached to the first shaft section an annular light-emitting element is arranged on the second shaft section. A measuring body with a load-dependent sensor is disposed between the shaft sections. The annular light-sensitive element is electrically conductively connected to the annular light-emitting element via the load-dependent sensor. A lamp element and a photoelectric element are arranged outside the shaft. Light from the lamp element is directed towards the annular light-sensitive element, and the light emitted by the light-emitting element is received by the photoelectric element and supplied to an evaluation unit.

A torque measuring device for measuring the torque in a shaft that is subjected to torsion and has two axially arranged shaft sections. A first shaft section functions as a driveshaft and a second shaft section functions as an output shaft and is connected to a load-dependent sensor. An annular light-sensitive element is attached to the first shaft section an annular light-emitting element is arranged on the second shaft section. A measuring body with a load-dependent sensor is disposed between the shaft sections. The annular light-sensitive element is electrically conductively connected to the annular light-emitting element via the load-dependent sensor. A lamp element and a photoelectric element are arranged outside the shaft. Light from the lamp element is directed towards the annular light-sensitive element, and the light emitted by the light-emitting element is received by the photoelectric element and supplied to an evaluation unit.

An elastic member of a torque sensor includes spring portions, a first fastening portion, and a second fastening portion. The spring portions are disposed in a radial pattern between the first and second fastening portions to connect the first and second fastening portions together. The spring portions have a dimension smaller in a direction tangential to a circle centered on an rotation axis than in a direction of the radial pattern. The distance between the first fastening portion and the second fastening portion is smaller than the dimension in the direction of the radial pattern. The optical encoders are opposed on, for example, the same diameter on a circumference of a concentric circle centered on a rotation axis of the rotational displacement of the elastic member. For example, averaging output signals from a plurality of optical encoders reduces influence of disturbance, such as cross-axis force.

An elastic member of a torque sensor includes spring portions, a first fastening portion, and a second fastening portion. The spring portions are disposed in a radial pattern between the first and second fastening portions to connect the first and second fastening portions together. The spring portions have a dimension smaller in a direction tangential to a circle centered on an rotation axis than in a direction of the radial pattern. The distance between the first fastening portion and the second fastening portion is smaller than the dimension in the direction of the radial pattern. The optical encoders are opposed on, for example, the same diameter on a circumference of a concentric circle centered on a rotation axis of the rotational displacement of the elastic member. For example, averaging output signals from a plurality of optical encoders reduces influence of disturbance, such as cross-axis force.

A detection device for a digital torque adapter includes a case having an operation area and a display area located on the outside thereof. A torque strain axle extends through the case. A recess is defined in one end of the torque strain axle. A circuit board having a receiving unit and a setting unit is electrically connected to the operation area and the display area. The case has a torque strain gauge located on the outer surface of the torque strain axle. An angle sensor is located in the case and detects the angle of the case and the torque strain axle relative to a horizontal plane. An accumulator is electrically connected to the circuit board and accumulates the angle detected by the angle sensor of each time that the wrench rotates, until the sum meets a pre-set value of angle of the setting unit.

Methods and systems for the absolute high-resolution measurement of angle of rotation of a shaft, which allow for concurrent measuring of axial displacement and/or encoded identification information, are disclosed. Included is a method for measuring characteristics of a rotating shaft comprising obtaining optical signals by optically probing one or more patterns having a leading edge and a series of symbols disposed at one or more circumferences of the shaft; oversampling the optical signals; measuring time of arrival for the leading edges and determining therefrom an amount of time between arrival of two or more of the leading edges; interpolating and extrapolating the amount of time between arrival of the leading edges; and determining therefrom one or more of shaft twist, angle of rotation and/or axial loading, translation, or displacement. The methods include optically probing a pattern disposed around the circumference of a shaft that comprises a series of wedge-shaped symbols.

Methods and systems for the absolute high-resolution measurement of angle of rotation of a shaft, which allow for concurrent measuring of axial displacement and/or encoded identification information, are disclosed. Included is a method for measuring characteristics of a rotating shaft comprising obtaining optical signals by optically probing one or more patterns having a leading edge and a series of symbols disposed at one or more circumferences of the shaft; oversampling the optical signals; measuring time of arrival for the leading edges and determining therefrom an amount of time between arrival of two or more of the leading edges; interpolating and extrapolating the amount of time between arrival of the leading edges; and determining therefrom one or more of shaft twist, angle of rotation and/or axial loading, translation, or displacement. The methods include optically probing a pattern disposed around the circumference of a shaft that comprises a series of wedge-shaped symbols.

In an embodiment, a relative deflection detector may include at least two structural arcs, and a predetermined number of means for measuring position capable of determining the relative deflection in a first component. The at least two structural arcs may be for example, comprised of a first and second structural arc whereby the first and second structural arcs are attached to the first component at respective first and second predetermined locations and whereby each arc is comprised of a respective sequence of indicators, such as, for example, codes inscribed on the outer circumference of each arc. The first and second structural arcs may be positioned in concentric and coplanar relationship with each other. The predetermined number of sensors may be comprised of a first and second optical encoder sensor each positioned in proximate and coplanar relationship with the first and second structural arcs so as to read the first sequence of codes, second sequence of codes, or both, and thereby detect positions of each structural arc (e.g., a first position corresponding to the first structural arc and a second position corresponding to the second structural arc). The first and second positions may be used to calculate and thereby determine a relative deflection of the first component.

In an embodiment, a relative deflection detector may include at least two structural arcs, and a predetermined number of means for measuring position capable of determining the relative deflection in a first component. The at least two structural arcs may be for example, comprised of a first and second structural arc whereby the first and second structural arcs are attached to the first component at respective first and second predetermined locations and whereby each arc is comprised of a respective sequence of indicators, such as, for example, codes inscribed on the outer circumference of each arc. The first and second structural arcs may be positioned in concentric and coplanar relationship with each other. The predetermined number of sensors may be comprised of a first and second optical encoder sensor each positioned in proximate and coplanar relationship with the first and second structural arcs so as to read the first sequence of codes, second sequence of codes, or both, and thereby detect positions of each structural arc (e.g., a first position corresponding to the first structural arc and a second position corresponding to the second structural arc). The first and second positions may be used to calculate and thereby determine a relative deflection of the first component.