SU678350A1 - Torque measuring device - Google Patents

Description

one

The invention relates to a measuring technique and can be used in the development of compensating-type micro-moment meters.

There are known devices for measuring moments that contain a movable part mounted in a suspension, and an angular position sensor of the movable part 1, These known devices do not

provide sufficient accuracy and sensitivity. The closest to the invention to the technical essence is a device for measuring moments, containing a movable part installed in the suspension, an angular position sensor of the movable part, a feedback amplifier and a torque sensor of galvanometric type 2. However, having the necessary sensitivity, the known device does not provide the required accuracy because of the error due to the quadratic nonlinearity of the static characteristic. The marked linearity is determined by the demagnetization effect of the magnet of the torque sensor by its winding current.

The purpose of the invention is to improve accuracy. In the proposed

device, this is achieved by introducing an amplifier gain adjustment block that realizes the ratio

 -It- doo

ty gain factor;

conversion factor

mr; no sensor sensor; nonlinearity coefficient

l torque sensor, determined by the demagnetization effect;

conversion factor A. no angle sensor. 1 schematically depicts FIG. but the proposed device; FIG. 2 is a section along the line A-A in FIG. one.

Claims (1)

The device consists of a housing 1, a movable part, including a tension-load 2 and a winding 3 of a galvanometric type torque sensor, a thread-like suspension 4, an angular position sensor 5 of the movable part, a feedback amplifier 6, current leads 7, a fixed magnet 8, a magnetic core 9 torque sensor and 3678350 unit 10 for adjusting the gain factor of amplifier 6. Under the action of the measured moment M, the mobile part rotates, causing the signal from sensor 5 to appear in the form of a direct current, which Zi and conductors 7 enters the winding 3 of the torque sensor, KCJimeH {the action of the measured torque. The output signal of the device is the current passing through the winding of the 10 moment torque sensor,. The static characteristic of the device (i.e., the dependence of its output signal on the measured torque) at a sufficiently high gain factor of the amplifier b, which provides almost zero sag in the winding 3 of the moving part (the change in the angular frame polarization proportional to the measured torque), has a nonlinear character The non-linearity of the characteristic is due to the demagnetization effect of the field H of the magnet 8 (see Fig. 2), the component of the Hp field Hj, the frame created by the feedback current in it. In this case, the demagnetization effect causes the appearance of a quadratic nonlinearity of the torque sensor. The quadratic nonlinearity depends on the angular deviation of the CC winding 3 from the pole line of the magnet 8 and. can be compensated by the quadratic nonlinearity of the torque sensor caused by the sag of the winding under the action of the measured torque. The sag of the winding, which is proportional to the measured torque, changes the conversion factor of a galvanometric type torque sensor according to the law corresponding to the distribution of the magnetic field intensity in the magnetic gap CHCTeNtj consisting of the magnet 8 and the magnetic core 9, namely, the cosine law, causing caNtJM the appearance of a quadratic nonlinearity characteristic of a torque sensor. It is established that the sign of the latter is opposite to the sign of non-linearity from the demagnetization effect. Full mutual compensation of these components of the non-linearity of the torque sensor can be ensured by selecting the proper sag by inserting into the device a unit 10 for a row. with le p about fi ltse c to os with vn no. gulirovaniya gain gain 6, body, based on the ratio of K, R-ddu. amplifier gain; torque sensor conversion factor; nonlinearity coefficient of the mental sensor, determined by the demagnetization effect; the transducer factor of the angle sensor. As a result of the introduction of this adjustment of the gain factor, the proportionality error of the device is reduced, and thus its accuracy is lost. The invention The device for measuring the moments, the rod of the movable part, mounted in the suspension, the angle-angle sensor of the movable part, the amplifier communication with the adjustment of the gain factor and the torque datgalvanometric type, due to the fact that with an increase in accuracy, the gain factor is amplified by the unit implementing the gain factor ratio of the amplifier; torque sensor conversion factor; torque sensor nonlinearity coefficient determined by the loosening effect; angle sensor conversion factor. Sources of information received during examination 1. Author's certificate of the USSR 893315, cl. 01 L 3/00, 1969, 2, USSR author's certificate 56494, cl. G 01 U 3/00, 1971,