The load sensor of the power-assist arm is based on the principle of strain gauge or pressure sensor, which converts load changes into electrical signals. The control system determines overload according to the set threshold value, and takes protective measures such as stopping action, alarm prompts, and recording data when overloaded to ensure the safety of the power-assist arm.
Working Principle Overview
The load sensor of the power arm is a device that can sense the load on the power arm. It usually works based on the principle of strain gauge or pressure sensor. When the power arm is under load, the sensor will undergo slight deformation or pressure changes, which will be converted into electrical signals.
Take the strain gauge load sensor as an example. The strain gauge is a component that can change its resistance value as the object deforms. When the power arm is subjected to force, the strain gauge installed in key parts (such as joints or load support structures) will deform as the structure deforms, and its resistance value will change. The change in resistance is converted into a voltage signal through a Wheatstone bridge circuit or other methods. This voltage signal is proportional to the load borne by the power arm.
Overload judgment mechanism
The load sensor transmits the detected electrical signal to the control system of the power arm. In the control system, the electrical signal threshold corresponding to the rated load value of the power arm is pre-set. When the electrical signal transmitted by the sensor exceeds this threshold, the control system will determine that the power arm is in an overload state.
For example, if the rated load of the power arm is 1000 kg, the voltage threshold output by the corresponding load sensor is 5V. When the voltage signal exceeds 5V, it means that the load borne by the power arm exceeds 1000 kg, and the control system will immediately start the overload protection program.
Overload protection measures
Stop action: The most common overload protection measure is to stop the current action of the power arm immediately. The control system will cut off the power source, stop the motor or hydraulic system of the power arm, prevent the power arm from being damaged due to excessive force, and avoid accidents caused by overload, such as heavy objects falling.
Alarm prompt: At the same time as stopping the action, the power arm will also send out an alarm signal. This alarm signal can be an audible alarm, such as a high-decibel beep, or a visual alarm, such as a flashing red light on the power arm’s operating panel. This can remind the operator that the power arm is overloaded and needs to be handled in time.
Recording data: The overload protection system also records the time when the overload occurred, the degree of overload and other related data. These data are very important for subsequent fault analysis and equipment maintenance. For example, by analyzing the overload data, it can be found whether some parts of the booster arm are damaged due to frequent overloads, or whether the overload is caused by improper operation.
