To improve the output signal quality of a load measurement by means of active magnetization, the invention provides a load measurement method for measuring a mechanical load on a test object (14), comprising: a) generating and applying a magnetic field to the test object (14); b) detecting a magnetic field changed by the test object (14) as a result of a mechanical load on the test object (14) by means of a first magnetic field detection device (20) to generate a first measurement signal (U1, UAB), c) detecting a magnetic field changed by the test object (14) as a result of a mechanical load on the test object (14) by means of a second magnetic field detection device (22) to generate a second measurement signal (U1, UAB), d) computationally determining a third measurement signal (UBT) from the first measurement signal (U1, UAB) and the second measurement signal (U2, UAT), and preferably comprising the steps of e) forming a difference from one (U2, UAT) of the first and the second measurement signals and the computationally determined third measurement signal (UBT) to produce an output signal, f) determining the mechanical load applied to the test object (14) based on the output signal. The invention also provides a corresponding load measurement device for carrying out the load measurement method.

A portable shippable automated calibration system for high torque power tools is disclosed. The system includes a self-contained highly durable and shippable container that may comprise a power source, central processor, visual user interface, mechanical interface for coupling with power tools to be calibrated, communications systems for communicating with a power tool being calibrated and/or with on-site or cloud based data systems. The system may be delivered to sites desiring on-site power tool calibration, tools are calibrated and updated calibration factors are automatically uploaded into the calibrated tool and a calibration certificate is published with the particulars of the calibration completion.

Methods and associated system for calibrating a torque device are provided. The method includes (I) providing a master torque tool having an accepted calibration, (II) attaching the torque device to be calibrated to an input shaft of a testing and calibration system, (III) energizing the torque device to a free spin under a no load and zero torque condition, (IV) performing a run down test by activating a torque engagement mechanism to transferred torque from the torque device to the master torque tool, (V) measuring a torque value from the master torque tool, the torque device, and the rotary inline torque transducer to generate a data set, (IX) repeating steps (IV) to generate a plurality of data sets and (V), and (VI) generating new calibration factors for input into a programmable control system of the torque device based on the plurality of data sets with a software package.

An apparatus for calibrating a rotational tool includes a communications interface configured to establish a wireless communications link between a rotational tool and a calibrator to communicate one of a tool torque measurement or a calibrator torque measurement via the communications link. The apparatus may further include calibration processing circuitry configured to receive the tool torque measurement measured by a tool torque sensor, and receive the calibrator torque measurement measured by a calibrator torque sensor. The calibration processing circuitry may also be configured to compare the tool torque measurement to the calibrator torque measurement to determine a difference value, aggregate the difference value with previously determined difference values to determine an updated torque calibration factor, and cause a torque calibration factor associated with a torque sensor of the rotational tool to be automatically replaced with the updated torque calibration factor in the memory of the rotational tool.

For more accurate load measurement, a load measuring arrangement includes a test object and a load measuring device for measuring a load on the test object. The load measuring device includes at least one magnetic field detection device for detecting a magnetic field parameter changing due to load at a measuring zone of the test object. The test object is work-hardened, at least at the measuring zone and at least in a near-surface region extending from a surface facing the magnetic field detection device to a depth of 20 μm, in such a way that it has a dislocation density of at least 5e8/cm.sup.2 and/or a residual stress of at least 400 MPa in amount.

A hydraulic braking device for testing industrial screwdrivers is arranged on a braking simulation bench, the braking device being controlled by an actuator and by a hydraulic control circuit which supplies pressure to the device on the basis of the indications of an electronic elaboration unit of the bench. Such a braking device is provided with coupling means for the screwdriver to be subjected to test and measurement transducers controlled by a processing unit, suitable for measuring the torque exerted by the screwdriver and the rotation angle, and such a device includes a memory which can be read and/or written by the bench electronic elaboration unit.

A torque detecting structure includes at least one torque detecting unit installed at a main shaft and including an electric connecting portion, at least one first terminal detachably and electrically connected to the electric connecting portion of the at least one torque detecting unit, and a torque detecting control unit electrically connected to the at least one first terminal.

A method of verifying torque measurements of a reaction torque transducer of an instrument drive unit includes a controller receiving a verification signal, generating an acceptable range of torques, receiving a torque signal, comparing the torque signal to the acceptable range of torques, and stopping a motor if the torque applied by the motor is outside of the acceptable range of torques. The verification signal is indicative of the current drawn by the motor and the torque signal is indicative of torque applied by the motor.

The invention relates to a method for adjusting a piezoelectric torque sensor of a measuring apparatus, which can be part of a test bench, for determining a torque applied to a test piece due to a force flux, wherein the measuring apparatus comprises a piezoelectric torque sensor and a second torque sensor based on a different measuring principle which is designed to continuously detect static torques, wherein the measuring apparatus is configured such that both torque sensors measure torques in the force flux, whereby a target measurement signal of the piezoelectric torque sensor is determined on the basis of a torque measurement by the second torque sensor, and whereby the detected measurement signal of the piezoelectric torque sensor is adjusted and output on the basis of the determined target measurement signal.

A test bench for screwdrivers comprises a hydraulic brake unit (11) provided with a coupling (12) for a screwdriver to be tested and angle and torque measurement transducers (15). The brake unit (11) is supplied by a proportional electrovalve (16) under the control of a PID controller (19) which receives an electrovalve control signal (22) from a control unit (26) so as to follow braking curves depending on the angle of rotation and/or torque measured. The bench comprises a memory (21) for storing different sets of parameters for the PID controller (19), which can be selected by the control unit (26) so as to have different control characteristics. A method for controlling the bench is also described.