In the manufacturing of modern household appliances, industrial machinery, and other equipment, assembly is no longer a task that requires a large amount of time and manpower to operate. With the specifications of 3C products becoming smaller, users have higher demands for product quantity and update speed, and the ordinary assembly level and speed of manual labor can no longer meet these requirements. Therefore, automated assembly production lines have emerged.

Among all assembly tasks, screw fastening is the most labor-intensive and tedious project. Just a single Mobile that we use in our daily lives requires hundreds of screws for structural tightening. In new energy vehicles, the screws for lithium batteries number in the thousands, and most importantly, the angle, torque, and other parameters of each screw must not have any errors. If ordinary manual labor is used, the labor costs are unlimited and will also increase the risk of product error rates. Therefore, in all assembly scenarios, a tightening system is one of the essential pieces of equipment.

Currently, the tightening systems on the market are roughly divided into servo tightening systems and hollow cup motor tightening systems.

Servo Tightening System:

The servo tightening system is an automatic tightening system device that allows the torque, angle, and other outputs of a regular screwdriver to vary freely with input signals (or fixed values). The so-called servo tightening system mainly relies on the precise pulse positioning of the servo motor to perform precise tightening work. It can be understood that the servo motor rotates a corresponding angle after receiving a pulse, achieving torque and positioning control, while the pulses emitted after the servo motor rotates can correspond with the received pulses, ultimately achieving feedback of torque and other values during the tightening process, realizing closed-loop control.

The basic servo tightening system is divided into three parts: the controller, cables, and servo screwdriver.
Controller: Built-in power supply, servo driver, display screen, and main control board, etc. Its main function is to issue commands to the screwdriver, drive the operation of the servo motor, and display feedback values.

Cables: The main function is to transmit commands and feedback data.

Servo Screwdriver: In addition to the accessories of a regular screwdriver, it also has a built-in servo motor. Its main function is to perform tightening operations according to commands and feedback torque, angle, and other values.

Main application scenarios: The servo tightening system is mainly used in assembly scenarios that require high precision, zero error, and data feedback. Its disadvantage comes from the characteristics of the servo motor: it cannot be applied to high torque tightening scenarios that require large inertia.

Hollow Cup Motor Tightening System:

The characteristics of the hollow cup motor tightening system mainly come from the coreless feature of the hollow cup motor. It is well known that the internal structure of general linear motors, stepper motors, and servo motors must have a rotor made of iron cores, while the lack of iron cores in hollow cup motors makes them much smaller in size and weight compared to ordinary motors. Moreover, their performance is also better than that of ordinary iron core motors. The energy conversion rate of ordinary iron core motors is at most 70%, while hollow cup motors can reach 90%. Additionally, their response speed far exceeds that of iron core motors.

Such characteristics allow the electric screwdriver in the hollow cup motor tightening system to be very lightweight. Currently, the hollow cup motor tightening systems on the market are mainly structured like screw guns, equipped with encoders and controllers to provide feedback on tightening data. However, due to the high cost of hollow cup motors, the tightening systems using hollow cup motors are naturally more expensive than servo tightening systems. The cost of foreign brand hollow cup motor tightening systems is generally around 30,000 to 40,000, so manufacturers that do not have high torque requirements generally choose the cheaper servo tightening systems.

Main application scenarios: Suitable for high torque scenarios such as the automotive industry. The tightening systems produced by well-known brands like MaTou and Atlas use hollow cup motors, primarily targeting the automotive industry. However, in terms of precision requirements, they still do not reach the level of servo motors.

A complete tightening system not only includes the basic tightening system but also needs to be equipped with a feeder, PLC, computer, and display screen. This way, it can be combined into a complete automatic tightening system on an automated production line.