Development of a Portable Intelligent Electric On-site Wrench Calibration Device

In large assembly workshop, such as automobile assembly workshop, the number of the wrenches is large. Some wrenches that used in fields are scattered. It is not convenient to send all such wrenches to laboratory for calibration at the same time, so it is necessary to develop a torque wrench calibration device which is suitable for on-site calibration. An intelligent indicator with MCU was developed,which can display and record the torque value, which is convenient for operators to record the data without paper and can check the data later. The intelligent indicator can also calculate the error at the same time, which improves the work efficiency by replacing manual calculation. A DS2401 chip was hidden in the transducer. It is cheap and has an unique sequence code, which is easy to identified by MCU. The MCU seeks the codes already stored in the indicator and matches linear correction coefficient to the transducer. It is first to use DS2401 chip to realize plug and play, which can avoid the measurement error even device damage caused forgetting switch the channel. The device also has an chargeable motor, which can save time and labor especially when mechanical gap exists and load a large torque value. The main characters of the device are auto-identifying transducer, powerful data handling similar to a compute and chargeable motor. All of these guarantee the device being intelligent and efficiency for the on-site wrench calibration.