Abstract:
A pressure sensor system comprises a force feedback loop. The force feedback loop is configured to receive a measured pressure sensor signal and generate a feedback signal based on the measured pressure and an electrostatic force. The electrostatic force is generated based on the feedback signal and combined with the measured force keeping the resultant sensor signal stable.
Abstract:
A device for controlling the tension of a yarn includes a gauge measuring tension of the yarn and optionally a brake driven by the tension gauge to vary braking of the yarn. The gauge comprises electromagnetic control means having a moveable control element subject to a force dependent on the tension of the yarn, and a control circuit. The latter circuit supplies the electromagnetic control means with a current so that the moveable control element remains virtually still in a given position, during variations of the yarn tension. This current is indicative of the tension of the yarn and is measured to obtain a measure of the yarn tension. The device can be associated with a yarn feeder having a drum and moveable eyelet coaxial with the drum.
Abstract:
A force measuring device of the electromagnetic compensation type is disclosed. The force measuring device includes a coil moving in a magnetic field, a display unit and a control circuit which returns the coil to its original position and supplies the display with the value of the forces being measured at substantially the same time. The device is also disclosed including a variable integration constant in the control circuit to provide a quicker response to small disturbances thus making the balance insensitive to vibrations.
Abstract:
An electromagnetic, compensating force-measuring or weighing device having at least one working coil movable in an air gap of a magnet system. At least two members for temperature compensation are positioned at different, spaced apart points. The compensating effect of these members on the active part of the system jointly produce a temperature compensating value which is optionally approximately equal to the exact value of the actual temperature curve. The members may be in the form of a plurality of minute particles of nonretentive material having a high negative coefficient of saturation magnetization distributed in the active part. The members may be formed of the afore-mentioned material and be positioned on the active part or be PTC or NTC resistors so positioned.
Abstract:
A method and apparatus for providing data related to the ice breaking efficiency of a hull of a vessel as the vessel passes through ice, and particularly for providing data related to the frictional forces experienced on the hull of the vessel as the vessel passes through ice. Movable means is carried on the hull of the vessel generally flush with the hull for displacement in response to forces applied thereto as the vessel passes through ice. The displacement of said movable means relative to the hull of the vessel is determined as a manifestation of frictional forces between the hull of the vessel and the ice. The movable means preferably comprises a generally coplanar relation therewith and flush with the outer hull skin. The plate is mounted on a plate suspending means which permits omnidirectional movement of the plate at least in the plane of the hull. In one embodiment, the degree of movement of the plate is sensed by a plurality of electromagnets carried by the hull of the ship and disposed at spaced positions adjacent the edges of the plate, with the electromagnets cooperating with a plurality of electrical conductors carried by the plate adjacent respective ones of the plurality of electromagnets, the electrical conductors producing electrical signals related to the degree of movement of the plate relative to the plurality of electromagnets. In another embodiment, plate movement is sensed by displacement probes in contact therewith and arranged to provide electrical signals representing displacement.
Abstract:
An electrostatically servo-controlled pendular micro-sensor includes a pendular element disposed so as to respond to a force representative of a physical quantity to be measured. To avoid the drifts affecting the stability of the micro-sensor, generated by the existence of unstable parasitic voltages that impair the voltages provided by a system servo-controlling the pendular element, the electrostatic forces generated to draw back the pendular element through servo-control voltages have a zero mean value. The control voltages are periodic voltages or series of electric signals of equal durations, each having, preferably, a zero mean value.
Abstract:
A force measuring instrument for determining the strength of an applied force by measuring the strength of an electromagnetic force developed so as to counterbalance the applied force, the instrument including a force coil, a displacement sensor for detecting any displacement occurring on a scale balance, an analog arithmetic unit for performing PD operation of analog detecting signals sent by the displacement sensor, a pulse converter for converting the analog signal into a signal having a frequency depending upon the magnitude of the analog signal, an up/down counter for counting up or down pulse signals from the pulse converter depending upon the polarity of the analog signal, a D/A (digital-to-analog) converter for converting the number of counts by the up/down counter into an analog signal, and wherein the sum of the output of the D/A converter and the output of the analog arithmetic unit is fed back to the force coil, thereby ensuring that the counts by the counter alone are used to determine the measurements.
Abstract translation:一种力测量仪器,用于通过测量产生的电磁力的强度来确定施加的力的强度,所述电磁力抵抗所施加的力,所述仪器包括力线圈,用于检测在刻度平衡上发生的任何位移的位移传感器, 用于对由位移传感器发送的模拟检测信号执行PD操作的模拟运算单元,用于将模拟信号转换为具有取决于模拟信号幅度的频率的信号的脉冲转换器,用于向上或向下计数的上/下计数器 取决于模拟信号的极性来自脉冲转换器的脉冲信号; D / A(数/模)转换器,用于将上/下计数器的计数数转换为模拟信号,其中, D / A转换器的输出和模拟运算器的输出被反馈到力线圈,从而确保仅使用计数器的计数 以确定测量。
Abstract:
A displacement detector yielding an electrical output signal that is linearly proportional to the extent of input motion. The input motion to be monitored is applied to the shiftable armature of a differential reluctance transducer constituted by a pair of transformers, each having a primary, a main secondary and an auxiliary secondary. Fed to the primaries is a high-frequency drive voltage generated by an oscillator whose amplitude is regulated by a feedback loop in which a feedback voltage taken from the auxiliary secondaries is compared with a reference voltage to provide a control voltage that so regulates the drive voltage oscillator as to cancel out the effect of temperature on the output signal derived from the main secondaries.