An electric cylinder is a mechatronic device that converts the rotary motion of a motor into linear motion. Its core working principle is that the motor drives the lead screw to rotate, and the screw drive mechanism converts the rotary motion into the linear reciprocating motion of the nut or the lead screw itself.

Core Components and Transmission MechanismAn electric cylinder is mainly composed of a motor, lead screw, nut, cylinder barrel and sensors. The motor (such as a servo motor or stepper motor) provides power, and the lead screw and nut form a screw drive pair: when the motor drives the lead screw to rotate, the nut moves along the axis of the lead screw, thereby pushing the load to achieve linear motion. Some new-type electric cylinders adopt a nut-reversing design, which drives the nut to rotate so as to drive the lead screw to perform linear motion, optimizing structural compactness.

Motion Control and Precision Realization

The control of an electric cylinder depends on the motor type and feedback system:

1. Servo Control: Servo electric cylinders monitor position in real time through encoders to form closed-loop control, achieving a repeatability precision of 0.01 mm level and high-speed response (with a speed of up to 0.1–2 m/s).

2. Pulse Control: Stepper motors control angular displacement by receiving pulse signals, thereby adjusting the stroke of the lead screw.

3. Transmission Technology: Transmission mechanisms such as ball screws or planetary roller screws are adopted to reduce friction loss, and improve the thrust range (10 kg to 35 T) and service life.

Types and Structural Characteristics

According to the motor layout and transmission mode, electric cylinders can be divided into three types:

1. Inline Type: The motor is installed coaxially with the lead screw, featuring a compact structure and being suitable for high-thrust scenarios.

2. Folded Type: The motor is parallel to the cylinder barrel, and synchronous belt drive is adopted to shorten the overall length, making it suitable for space-constrained environments.

3. Vertical Type: The motor axis is perpendicular to the lead screw, and a reduction mechanism is used to achieve a large reduction ratio and low-power drive.