SU559107A1 - Strain gauge device - Google Patents

Description

one

The invention relates to a measurement technique and can be used to study and measure the stresses and deformations of mechanical elements and structures.

A strain gauge device containing a two-one amplifier is known, the output of which is connected to the output unit. In parallel with one input of the amplifier, a strain gage transducer of the iroTenmioMepriic circuit is included. The second input of the terminal is connected to the negative feedback circuit 1.

11 is a well-known thermometric device, containing two strain generators, two usable spikes and a VALVE block with an adder, to which noAicriioHOHbi outputs of amplifying channels 2.

Strain gauges included on pavement. The Ianr / Kenya nutrition of one motovaya scheme relative to apyroii is shifted by 900.

The disadvantage of the known devices is that it is impossible to make measurements of diaoamich :-;

tic deformations at varying temperatures.

The aim of the invention is to compensate for the temperature errors of strain gauges when measuring both static and dynamic deformations of the product.

This is achieved by a heme that tepzopreooO.CH .; the drivers are included according to the potential;

Fig. 11 shows the elecgrich; the device layout

The device contains the first noiei metric circuit 1, the state of the shu.-elastic resistor 2 and null-type.

iKOi ten-transform ate 3, the second TI is tents etricho; sku o scheme 4, const. c .;

:, - u and the floor at Provo / l nor the new theisoprecognition .h .;

Olya 5 and bsglaslnogo rez1; sgo;: a v, feather

yen-lms-ln 1st KnHiui 7, BTOf-ioii wuxi; 1 ii i-, i

Claims (2)

; -i channel 8, output unit 9 with adder 10 and Power supply 11 of circuits 1 and 4. Tension transducers 3 and 5 of the circuits are connected in series and connected to the terminals of power supply 11. A strain gauge 3 is connected in parallel to the input of channel 7. Parallel to the input of channel 8, a resistor 6 is connected, the outputs of channels 7 and 8 are connected to the adder 10 of the output unit 9. The device works as follows At O7x: strain strain resistance 3 and 5 the voltage of the device will be equal to the entire voltage of the power supply of the block 9. When the measured force acts on the strain gauges 3 and 5, their resistance changes by the value of LT. At the output of the channels 7 and 8 comes from change for example. by the value of dU, which is proportional to the magnitude of the applied strain. uV depends on the applied strain: compression or tension. Output voltage is linearized and temperature compensated in a strain gauge device due to the fact that Strain gage transducers 3 and 5 are included in different arms of the patient circuit 1 and 4. The voltage from circuits 1 and 4, proportional to the applied deformation, flows through channels 7 and 8 on the adder 1O of the output unit 9. Since the Tenzo converters 3 and 5 are of the same type and operate under the same conditions, the increments caused by non-linearity and the effect of temperature will have the same order, but With opposite signs. Consequently, they compensate each other when adding in the adder 10. The use of two strain transducers connected in parallel channels provides an increase in the strain sensitivity of the strain gauge device twice. Using variable resistors of channels 7 and 8 and adder 10, the magnitude of the transfer coefficients is selected, which ensures the linear law of variation of the output voltage and thermal compensation. Strain gauge device containing two strain gauges, two amplification channels and an output unit with an adder, to which the amplifiers channels are connected, characterized in that, in order to compensate for temperature errors, the strain gauges are connected by potentiometric circuit, parallel to the input of the first amplification channel, the strain gauge is first potentiometric circuit, and parallel to the input of the second amplifying channel the ballast resistor is switched on to the second potentiometer trichesky scheme. Sources of information taken into account in the examination; 1. Zrler V. Walter L. Electrical measurements of non-electric quantities by semiconductor strain gauges, Mir, 1974, p. 228. 2. USSR author's certificate number 357455, M. Cl. Q 01 B 7/16, 197О (prototype). (/ Ll -one