SU1232967A1 - Device for measuring torque - Google Patents

Abstract

The invention relates to instrumentation engineering and can be used for continuous contactless measurement of torque in drives and mechanisms. The purpose of the invention is to increase measurement accuracy. The device contains rigidly mounted on an elastic shaft 3 at a certain distance from one another the gear disks 1 and 2, mounted so that, in the absence of shaft twisting, the teeth opposing on its axis coincide on the profile. The device also contains a measurement circuit consisting of contactless sensors 4 and 5 (BD), a carrier frequency generator 6 providing synchronous power to BD 4 and 5, amplifiers 7 and 8, subtraction unit 9, limiting amplifier 10, one output of which is connected with the torque indicator 11, and the other with the frequency meter 12. The introduction of new elements and the formation of new connections between the elements of the device make it possible to measure high-frequency components of the variable variable torque. 3 il. i (L

Description

The invention relates to instrumentation engineering and can be used for the continuous contactless measurement of torque in drives and mechanisms.

 The aim of the invention is to improve the accuracy by allowing the measurement of the high frequency components of variable torque.

Figure 1 shows the diagram of the device; Fig. 2 shows gear wheels with teeth having an Archimedean spiral profile and a corresponding graph of the change in the gap between the tooth surface and the sensor when the disk is rotated one tooth; Fig. 3 shows graphs illustrating a sequence of converting electrical signals from sensors by a measuring circuit.

The device consists of two toothed disks 1 and 2, rigidly mounted on an elastic shaft 3 at a certain distance from each other, on which are made a tooth (Fig. 2) with a profile, described by an Archimedean spiral.

The discs are mounted on the shaft in such a way that, in the absence of shaft twisting, the teeth opposing along its axis coincide on the profile. The device also contains a measurement circuit consisting of two contactless sensors 4 and 5 for converting the gap between the sensor and the 1 tooth profile 1 into an electrical signal, a carrier frequency generator 6, which provides synchronous power to the sensors 4 and 5, two amplifiers 7 and 8, a subtraction unit 9, a limiting amplifier 10, one output of which is connected to a torque indicator 11, and the other to a frequency meter 12. The inputs of amplifiers 7 and 8 signals are connected to the outputs by sensor 4 and 5, and the outputs to the inputs of block 9 subtraction

The device works as follows.

When the shaft 3 rotates and it is not twisted (idle), the 4 and 5 linear displacement sensors powered by the carrier frequency generator 6 (Fig. 3a) convert the variable value of the gap 4 into identical, amplitude-modulated electrical signals that are fed to amplifiers 7 and 8 and, after amplification, to the circuit of subtraction unit 9. Due to

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the fact that the signals are equal in amplitude and phase in time, since there is no tooth shift in the disks 1 and 2, the difference signal at the output of the subtraction circuit will be zero. When the elastic shaft 3 is loaded with a torque, the gear discs 1 and 2 rotate relative to each other by an angle proportional to the torque. In this case, a difference occurs in the gaps L (Fig. 2) between sensors 4 and 5 and the corresponding teeth, and amplitude-modulated signals are shifted to the input of the subtractor unit in phase (Fig. 36, c). As a result of their subtraction at the output of the subtraction unit 9, a signal is generated, the proportional torque value (Fig. 3g), which, after detection and limitation in the limiting amplifier 10, is fed to the input of the frequency meter 12 (Fig. Rear) to control the frequency rotation and the input of the indicator 11 torque (Fig. Ze).

Thus, any change in the torque causes a change in the difference in the gaps between the sensors and the tooth, which leads to a corresponding change in the magnitude of the voltage applied to the input of the torque indicator.

Claims (1)

Invention Formula A device for measuring torque, which contains two rigidly mounted on an elastic shaft at a distance from one another gear wheels with identical teeth, the first and the second contactless sensors mounted opposite the gear disks and connected to the carrier frequency generator and respectively the first and: the second amplifiers whose inputs are connected to the first and second inputs of the subtraction unit, the output of which is. It is connected through an amplifier-limiter with a torque indicator and a frequency meter, characterized in that, in order to improve accuracy by allowing measurement of high-frequency components of the torque, the teeth tooth profile is made along an Archimedean coil, and proximity sensors represent is a linear displacement transducer. J- Fng.2 WWinAAAA / WX