Harmonic Pin Drive With Flexible Traction for High Gear Ratios
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Solution Overview
Problem
Existing gear systems lack efficiency in providing high gear ratios with reliable and simple setups, particularly in motor-gear units and vehicles, where the connection of input and output shafts to the gear is not optimally addressed.
Innovation Solution
A gear system with an outer wheel and an inner wheel positioned concentrically, featuring a ring-shaped or cylindrical traction mechanism between them, where a revolving transmitter lifts the traction from the inner wheel's outer periphery and pushes it onto the inner periphery of the outer wheel, allowing for high gear ratios and flexible connection options.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional gear system is used, then the structure is simple, but the gear ratio is limited and efficiency is low
Solution Approach 1:
The gear system is divided into two independent concentric wheels (outer wheel and inner wheel) that can rotate in opposite directions. Each wheel has its own circumference engaged by the chain, allowing the system to achieve high gear ratios through the differential rotation of segmented components rather than a single complex gear mechanism.
Solution Approach 2:
The inner wheel is positioned concentrically inside the outer wheel, creating a nested configuration where both wheels share the same central axis. This nested arrangement allows the chain to engage both wheels simultaneously, enabling high gear ratios in a compact structure without requiring multiple stacked gear stages.
2Productivity
If a complex connection method is used for input and output shafts, then the gear ratio can be high, but the device complexity increases
Solution Approach 1:
The concentric wheel configuration allows the same basic structure to serve multiple connection configurations. The input shaft can be connected to either the outer wheel or inner wheel, and the output shaft can be connected to the other component, providing flexible multi-functional connectivity without requiring different mechanisms for different gear ratio configurations.
Solution Approach 2:
The system allows reversal of input and output connections. If the input shaft is connected to the outer wheel and output to the inner wheel for one gear ratio configuration, the connections can be inverted (input to inner wheel, output to outer wheel) to achieve a different gear ratio, eliminating the need for complex switching mechanisms.
3Loss of energy
If friction is reduced through design, then efficiency improves, but the device complexity may increase
Solution Approach 1:
A chain serves as an intermediary element between the two concentric wheels, transferring power through engagement with the circumferences of both wheels. This intermediary mechanism reduces direct frictional contact between the wheels themselves while maintaining efficient power transmission through the chain's tensile and flexural properties.
Solution Approach 2:
The system replaces direct mechanical contact and friction-based power transmission between wheels with a chain-driven system. The chain engages with the wheel circumferences through a combination of tension, bending, and minimal sliding friction, substituting high-friction direct contact with lower-friction chain engagement.
Data Source
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AI summary
The application discloses a harmonic pin drive which comprises at least one outer ring gear with inner teeth that are adapted to the shape of pins of a pin ring, a transmitter for connecting to a rotor of an electric motor, a ball bearing that is supported on the transmitter and an arrangement of flexible means. The flexible means are distributed essentially on the circumference of a radius and the flexible means are provided for attachment to a casing. Furthermore, the flexible means comprise openings for inserting pins of the pin ring. Furthermore, an output shaft is provided for receiving a rotation of the outer ring gear.