Pantograph Linkage Mechanism for Mine Trolley Current Collection

The pantograph is divided into multiple segments (first arm, second arm, third arm) that can move relative to each other. This segmentation allows the pantograph to achieve a large movable range through the coordinated movement of multiple smaller segments rather than requiring a single large, heavy structure.

The pantograph arms are arranged in a nested configuration where the second arm is positioned within the structure formed by the first arm, and the third arm is positioned within the structure formed by the second arm. This nesting allows the pantograph to fold into a compact form when not in use while still achieving a large extended range when needed.

The pantograph employs a dynamic linkage mechanism where the arms are connected through pivots that allow relative movement. This dynamic structure enables the system to generate the required lifting force through mechanical advantage and geometric relationships rather than requiring a large, complex actuator.

The patent introduces an intermediary mechanism (the linkage system between the air cylinder and the pantograph arms) that transforms the force from a compact air cylinder into the large push-up force needed. This intermediary mechanism uses the geometric relationships and mechanical advantage of the linkage to amplify the force.

The spring force is dynamically adjusted through the linkage mechanism. As the pantograph extends or retracts, the geometric relationships change, which automatically modulates the spring force to maintain appropriate contact pressure without requiring an excessively strong spring.

The patent changes the parameters of the spring system by using a shorter spring with modified stiffness characteristics, combined with the geometric parameter changes in the linkage mechanism. This allows the system to maintain the required pressing force over the entire movable range without requiring a long, strong spring.

By segmenting the pantograph into multiple lighter arms connected by pivots, the overall weight is reduced while maintaining structural strength through the distributed structure. Each segment can be optimized for minimal weight while providing the necessary local strength.

The patent employs composite construction in the pantograph arms, combining materials with high strength-to-weight ratios. This allows the structure to maintain the required strength for supporting the extended range while minimizing the weight to improve followability.