Inspection method for sensor failure of helmet strap tensile tester
The measurement of the force value of the helmet strap tensile testing machine is completed by the force sensor, the expander and the data processing system. It is known from the mechanics of materials that, under the premise of small deformation, the strain at a certain point of an elastic element is directly proportional to the force on the elastic element, and also to the elastic deformation. Taking the sensor of S-type testing machine as an example, when the sensor is under the effect of pulling force P, because the strain of elastic element is in a positive proportion to the size of external force P, Gu hereby connects the strain gauge to the measuring circuit, and then the output voltage can be measured by measuring the ride output voltage, and then the output force can be measured.
In the process of using the helmet strap tensile testing machine, it is inevitable to have all kinds of abnormalities, especially in the case of displacement of the product itself or inaccurate induction of the product, so it is very important to check the reason of displacement sensor of the tensile machine. Let's analyze the possible problems in the position of the electronic helmet strap tensile testing machine?
Because the electronic helmet strap tensile testing machine system is a closed-loop system, to judge which part of the system has a fault, first disconnect the loop in the system, so that the system becomes an open-loop system. If the sensor signal is normal, the feedback signal of the displacement sensor must be disconnected to make the system open-loop. At this time, a control actuator moving signal is sent out from the workstation, and then the feedback value of the sensor is measured. After several repetitions, when the feedback data of the sensor is measured as a linear change line, it is determined that the sensor is normal
After eliminating the fault of the displacement sensor, check whether the amplifier unit is normal, and disconnect the output signal of the amplifier unit first. Remove the output wiring, add a DC input signal to the amplifier unit through the workstation, and measure the output of the generator unit. After several repetitions, the measured output signal of the amplifier unit changes linearly to determine whether the amplifier unit is normal.
In addition to the above reasons, the product sensitivity is also a very important concern. A good electronic helmet strap tensile testing machine can withstand various environments and changes. The most important thing is to be very sensitive to the accuracy.