Analysis of the Working Principle of Forklift Steering Systems

1. Rear-wheel steering design Steering wheel position: The steering wheel of a forklift is generally located at the rear (drive wheel), while the front wheels are load-bearing wheels. This design reduces the turning radius and facilitates flexible steering in rack aisles or narrow areas. Ackermann geometry: During steering, the rear wheels rotate at different angles through a linkage mechanism, minimizing the trajectory difference between the inner and outer wheels and reducing tire wear. 2. Types of steering systems (1) Mechanical steering (manual/hydraulic assist) Steering wheel + steering gear: The steering wheel drives the rear-wheel steering through a mechanical linkage (such as rack and pinion or recirculating ball steering gear) or a hydraulic power-assist system. Hydraulic assist: Most modern forklifts use hydraulic power steering (HPS), which provides power through a hydraulic pump to reduce the driver's operating effort. (2) Electric power steering (EPS) Electric forklifts commonly use a motor to directly drive the steering system. Sensors detect steering wheel input, and the ECU controls the motor output steering force, making it energy-efficient and precise. 3. Key components Steering axle: Carries the rear wheels and performs the steering action, with built-in steering knuckles and kingpins. Steering cylinder (hydraulic system): Hydraulic oil pushes the piston rod to move left and right, driving the steering wheels to rotate. Steering control valve: Adjusts the flow direction of hydraulic oil according to steering wheel input. Feedback mechanism: Ensures that the steering wheel angle is synchronized with the wheel turning angle. 4. Workflow Driver input: The driver turns the steering wheel, transmitting torque through the steering shaft. Power assistance intervention: In the hydraulic system, the steering pump pressurizes the oil to push the cylinder into action; in the electric system, the motor drives the steering mechanism. Wheel steering: The steering linkage transmits force to the rear wheels to achieve left and right steering. Stability control: Some forklifts are equipped with speed-sensitive steering (flexible at low speed, stable at high speed). 5. Special designs Multi-directional forklift: Some forklifts (such as side-loading forklifts) allow the wheels to rotate 90° for lateral travel. Steer-by-wire: High-end electric forklifts may eliminate the mechanical connection and control the steering motor entirely through electrical signals. Advantages and precautions Advantages: Rear-wheel steering provides an extremely small turning radius, making it suitable for warehouse operations. Maintenance points: Regularly check the hydraulic oil level, steering linkage lubrication, tire wear, and steering sensitivity. Through this design, forklifts can efficiently complete handling tasks in limited spaces while ensuring precision and safety of operation.