The fixed-type electric chain hoist is a lightweight, compact lifting device that is smaller in size and lighter in weight than wire-rope electric hoists, and is widely used in industrial settings such as factories, docks, and warehouses. Compared with wire-rope electric hoists, fixed-chain hoists feature a simpler structure, easier installation and operation, higher reliability, and a broader range of applications. Building on the traditional manual-pull hoist and wire-rope electric hoist, we have developed the LCK and LCR series of lightweight chain hoists—more portable and practical designs. The key advantages of these optimized designs are their rational structure and exceptional stability and reliability. Next, let’s take a closer look at the structural components and design features of the fixed-type electric chain hoist!

　　I. The fixed-type chain-type electric hoist is developed through the modification and upgrading of imported chain-type electric hoists from abroad, and the new model primarily features the following characteristics:

　　1. A disc-brake motor is used to replace the chain-pull and braking components of the manual hoist, providing sensitive, precise, and reliable braking.

　　2. A planetary gear reducer is used to increase the output torque; it features a high gear ratio, compact size, light weight, and high stability and reliability.

　　3. A torque limiter is employed to prevent overloading, thereby protecting the disc-type motor and the transmission system from damage and ensuring the crane’s stability and reliability. Figure 1 shows the assembly drawing of the LCR-series chain-type electric hoist.

　　4. Structure and Product Types of Heavy-Duty Chain Electric Hoists

　　A stationary electric chain hoist consists of an electric motor, a transmission mechanism, and sprockets. Its key difference from a wire-rope electric hoist is the replacement of the wire rope with a chain, which addresses the latter’s drawbacks of large size and heavy weight. The typical lifting capacity ranges from 0.5 t to 35 t, with a lifting height of 3 to 120 m.

　　Currently, our stationary chain-type electric hoists mainly comprise two series: the LCR series and the LCK series. Within each series, there are also slower-speed models. These stationary chain-type electric hoists use a disc-brake motor as the power source and a cycloidal pinwheel reducer to reduce speed and increase torque. They feature a compact structure, small footprint, light weight, high efficiency, convenient operation, reliable braking, and simple maintenance; however, they are prone to wear and have complex manufacturing and assembly processes. The chain-type electric hoist with a low-tooth-difference reducer, on the other hand, employs a low-tooth-difference planetary gear train in the drive shaft system for speed reduction, along with a conical-surface friction transmission pair adjusted by disc springs.

　　II. Structural Design of Fixed-Style Chain-Driven Electric Hoists

　　1. Transmission System Design

　　1) Electric motor: Equipped with a thermal protection device to prevent overheating and subsequent motor burnout.

　　2) Brake: A mechanical brake is used, featuring copper-wire-reinforced asbestos friction material, which can stably support the load when the motor is stopped.

　　3) Gear reducer: used to reduce rotational speed, increase torque, and transmit power.

　　4) Limit switches: Equipped with upper and lower electronic limit switches to prevent the chain from being over-tightened.

　　5) Torque limiter: This device allows the motor to run idly in the event of overload or over-tightening, thereby preventing damage to the motor and the mechanical transmission system caused by such conditions. 6) Hook and chain: The hook is forged from alloy steel and undergoes a rigorous heat-treatment process, ensuring it will not fracture under overload and can be released gradually. The chain, after heat treatment, exhibits excellent wear resistance, corrosion resistance, and long service life.

　　2. Geometric Parameter Design of Gear Drives

　　The design of the geometric parameters for the gear transmission in fixed-type chain electric hoists typically employs helical gears to ensure reliability, as they can reduce meshing-induced impacts and vibrations, thereby extending service life. This specialized design enhances gear durability, and since the gears are made from alloy steel and undergo meticulous heat treatment, they achieve high strength.

　　The LCK and LCR series of stationary chain-type electric hoists are designed with high-strength load chains, T-grade strength hooks, and wear-resistant sprockets. They feature a gear set consisting of two sets of plate gears and a 5-tooth short shaft that mesh directly with the gears, thereby enhancing transmission reliability, reducing the load on the gear teeth, and minimizing the overall unit size. This results in a compact, lightweight, and space-saving design. In place of the conventional hand lever and braking mechanism, a disc-brake motor is employed, complemented by a torque limiter to prevent overloading and ensure consistent braking performance. Additionally, the outer wall panel and cover plate are integrated into a single structure, significantly improving the hoist’s resistance to impact from drops.

　　The foregoing sections have outlined the structural composition and design features of fixed-type electric chain hoists. For more information, please feel free to contact us at any time!