41results about How to "Small linear error" patented technology

The invention discloses a gradient coil of a nuclear magnetic resonance spectrometer. The gradient coil is composed of a main coil and a shielding coil coaxially arranged outside the gradient coil, wherein several groups of the main coil are symmetrically distributed up and down in the axial direction of the coil. Two sets of coil windings, the upper two sets of coils are opposite to the lower two sets of coils, the shielding coil is two sets of upper and lower symmetrically distributed coil windings with opposite winding directions, all winding coils are connected in series, the shielding coil and the main coil A distance of 4.3-5.3 mm is preferably maintained between them, and a heat insulating component is also provided in the inner space of the main coil. The gradient coil realized according to the present invention obviously improves the coil efficiency, and a gradient magnetic field with a strength greater than 50Gs / cm@10A and a linear error less than 0.5Gs@10A can be obtained with a simple algorithm and process, and it can ensure that the gradient field is stable when the temperature changes stability in the experiment.

The invention relates to a two-cantilever large-deformation strain measurement sensor. A left end holder is provided with a left end connecting rod, a right end holder is provided with a right end connecting rod, the right end of the left end connecting rod is provided with a fixing body mounted at the left end in a sleeve, the left end of the right end connecting rod is provided with a wedge-shaped body mounted at the right end in the sleeve, the right end of the fixing body in the sleeve is provided with a spring leaf and a centering / spacing slide rod positioned in the spring leaf, the centering / spacing slide rod is externally provided with a compensating spring, the right end of the centering / spacing slide rod is arranged on the wedge-shaped body, the spring leaf is provided with even-numbered (at least four) resistance strain gages, and all the resistance strain gages form a full bridge which uses a lead wire for output. By using the W-shaped spring leaf, the invention greatly improves the sensitivity; and as both ends of the spring leaf are fixed, the two-cantilever large-deformation strain measurement sensor can still have high antijamming capability and stability even if the external loading force changes a lot. The two-cantilever large-deformation strain measurement sensor provided by the invention has the advantages of high sensitivity, easy calibration process, less linearity error, high antijamming capability, good stability and the like, and can be used as a large-deformation displacement sensor.

A plane strain measuring sensor has the characteristics: at least two bolt holes or locating slot holes are processed in top surface axial direction of multi-direction support, radial hole processed on the same plane with lateral face radial direction is corresponding and interconnected to the bolt holes or locating slot holes of top surface, at least two connecting rods has one end separately set in radial hole of multi-direction support and another end linked separately to the sensors on the same plane but different directions. Tested in laboratory and by bridge load test, the invention is proved to have the advantages: rational design, high sensitivity, easy standardization, small linear error, excellent interference killing and dampness feature, good stability, changeable standardization, wide use, apart from these, after linking to static strainometer or dynamic strainometer, it can measure strain on the same plane but different directions of building unit such as highway bridge and railroad bridge and that of metal unit as well.

The invention provides a high-precision dip angle measuring instrument based on an over-sampling technology. According to the high-precision dip angle measuring instrument, a microaccelerometer FXLN8361 is adopted as a measurement element, a high-performance low power-consumption single chip microcomputer MSP430F5529 is adopted as a controller, inclination of the measured face is detected through a biaxial measurement method, and constancy of sensitivity of the dip angle is achieved; through an over-sampling algorithm, the measured minimum angle can be improved to 0.05 degree from 0.8 degree.

The invention discloses a method for measuring the rotor speed of a turbo generator and a device thereof. The method comprises the following steps: converting the rotor speed into a pulse electrical signal through a sensor; carrying out F / V conversion on the pulse electrical signal, wherein U(f) refers to the converted voltage signal, f refers to the pulse electrical signal, f1 and f2 refer to two predetermined pulse electrical signal values, Umax refers to a predetermined voltage value; carrying digital-to-analogue conversion on the voltage signal after the F / V conversion; and converting the voltage signal after the F / V conversion into digital quantity through a data acquisition unit. In the method, F / V conversion is carried out on the pulse electrical signals by stages, with respect to the voltage signal which is converted according to the U(f) = f*k1 linear form in prior art 2, because k is more than k1, the frequency range corresponding to the converted voltage signal in the predetermined scope is small, and the caused linear error is also small, the measurement is insusceptible to interference wave, and the measurement error of the rotor speed is small.