The internal structure of a hand chain hoist trolley typically consists of several key components that work together to facilitate lifting and movement of heavy loads. While designs may vary slightly between manufacturers and specific models, the fundamental components are generally consistent. Here are the main internal parts of a hand chain hoist trolley:

Chain: The chain is a crucial component of the hoist system, responsible for bearing the load and transmitting the lifting force. It is typically made of high-strength alloy steel and consists of interconnected links.

Load Chain Wheel: The load chain wheel, also known as the lifting wheel or sprocket wheel, is a grooved wheel around which the load chain is wrapped. When the hand chain is operated, it turns the load chain wheel, causing the load chain to lift or lower the load.

Gearing Mechanism: The gearing mechanism is responsible for converting the manual force applied to the hand chain into lifting force. It typically consists of gears, shafts, and bearings arranged in a gearbox. The gearing ratio determines the mechanical advantage and lifting capacity of the hoist.

Brake Mechanism: A brake mechanism is incorporated to control the descent of the load and prevent it from free-falling when the hand chain is released. This mechanism may include friction brakes, pawl-and-ratchet systems, or other types of braking devices.

Lifting Mechanism: The lifting mechanism includes components such as hooks or load attachments for securing the load to the hoist, as well as mechanisms for engaging and disengaging the load chain with the load chain wheel.

Trolley Wheels: The trolley wheels are mounted on axles and enable the hoist to move horizontally along a beam or track. They are usually made of durable materials such as steel or nylon and are designed to roll smoothly along the beam.

Trolley Frame: The trolley frame provides support for the trolley wheels and serves as the structure to which the hoist body is mounted. It may be adjustable to accommodate different beam widths and configurations.

Bearings and Bushings: Bearings and bushings are used throughout the hoist trolley to facilitate smooth movement of components such as gears, shafts, and trolley wheels.

Handle and Controls: The handle is used to operate the hand chain, allowing the user to raise, lower, and maneuver the load. Some hoists may also include controls or levers for adjusting lifting speed, direction, or other parameters.

Overall, the internal structure of a hand chain hoist trolley is designed to provide reliable and efficient lifting and movement of heavy loads while ensuring safety and ease of operation. Regular inspection, maintenance, and lubrication are essential to keep the components in good working condition and prolong the hoist's service life.