Abstract: A magnetoinductive flowmeter incorporates an electromagnetic circuit with at least one coil and a minimum of two detachably interconnected components of a magnetic material. One of the components features a resiliently deformable spring section that presses against the other component. The result is an easy-to-assemble magnetoinductive flowmeter that can be manufactured with substantial production tolerances.

Abstract: There is described a sensor comprising an excitation winding, a signal generator operable to generate an excitation signal and arranged to apply the generated excitation signal to the excitation winding, a sensor winding electromagnetically coupled to the excitation winding and a signal processor operable to process a periodic electric signal generated in the sensor winding when the excitation signal is applied to the excitation winding by the signal generator to determine a value of a sensed parameter. The excitation signal comprises a periodic carrier signal having a first frequency modulated by a periodic modulation signal having a second frequency, the first frequency being greater than the second frequency. In this way, the sensor is well suited to using digital processing techniques both to generate the excitation signal and to process the signal induced in the sensor windings. In an embodiment, the sensor is used to detect the relative position of two members.

Abstract: A Position Sensor comprises: one or more excitation windings; a signal generator adapted to apply excitation signals to the or each excitation winding; tag means displaceable relative to said excitation windings; one or more sensor windings electromagnetically coupled to said excitation windings such that in response to said excitation signals being applied to said excitation windings, there is generated sensed signal in the or each sensor winding; and a signal processor adapted to process said sensed signals to determine the position of said tag means in any location in the X, Y and Z planes essentially in accordance with phase values or in accordance with phase values and amplitude values.

Abstract: A Position Sensor comprises: one or more excitation windings; a signal generator adapted to apply excitation signals to the or each excitation winding; tag means displaceable relative to said excitation windings; one or more sensor windings electromagnetically coupled to said excitation windings such that in response to said excitation signals being applied to said excitation windings, there is generated sensed signal in the or each sensor winding; and a signal processor adapted to process said sensed signals to determine the position of said tag means in any location in the X, Y and Z planes essentially in accordance with phase values or in accordance with phase values and amplitude values.

Abstract: The present invention provides a position sensor which is suitable for use in a piston and cylinder assembly. The position sensor includes a movable field modifying member which is operable to vary the inductance of a sensor winding, whereby the position of the field modifying member relative to the sensor winding can be determined by monitoring the inductance of the sensor winding. The position sensor also includes a compensation winding which is arranged to have a common coupling with the field modifying member whereby a signal output from the compensation winding can be used to compensate for variations in the signal level output by the sensor winding caused by, for example, temperature variations of the system.

Abstract: A magnetic flow meter includes a cylindrical vessel within which electrodes are placed directly opposite each other about a magnetically permeable core. In that way, two flow channels are obtained in the vessel. A common magnetic field is applied across both flow channels. The magnetic flow meter is used in conjunction with a controller which monitors amplitude modulated signals representative of applied magnetic field and induced electric field. These amplitude modulated signals are passed to Sigma-Delta modulators, which directly digitise the amplitude modulated AC signals into digital pulses. The controller is capable of monitoring reverse flow through the meter, and to store results until forward flow resumes. Moreover, the controller generates a driving signal for coils which generates a magnetic field, the coil being placed in conjunction with a capacitor which causes resonance. This reduces power consumption by the coil in driving the meter.

Abstract: The present invention provides a position sensor which is suitable for use in a piston and cylinder assembly. The position sensor includes a movable field modifying member which is operable to vary the inductance of a sensor winding, whereby the position of the field modifying member relative to the sensor winding can be determined by monitoring the inductance of the sensor winding. The position sensor also includes a compensation winding which is arranged to have a common coupling with the field modifying member whereby a signal output from the compensation winding can be used to compensate for variations in the signal level output by the sensor winding caused by, for example, temperature variations of the system.