Helical Gear Transmission With Radial Thrust Collar Offset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current gear transmissions with helical gears face inefficiencies due to additional axial loads, which increase size and cost, and existing solutions either compromise on efficiency or design complexity to mitigate these issues.
Innovation Solution
The solution involves spatially separating contact surfaces for traction and overrun torques, with contact points radially offset, optimizing thrust collars for efficiency during traction and cost-effectiveness during overrun, using cone-shaped races and integrated or separate components to minimize components and complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If helical gears are used to reduce noise, then acoustic performance is improved, but axial loads increase requiring additional bearing support
Solution Approach 1:
The invention divides the single axial load support function into two separate thrust collars, each handling axial loads in opposite directions. This segmentation allows the helical gear to maintain its noise-reducing benefits while the divided thrust support system efficiently manages the axial loads generated by the helical tooth contact.
2Device complexity
If thrust collar contact point is arranged below root diameter, then design complexity is reduced, but sliding speed increases reducing efficiency
Solution Approach 1:
The invention applies different contact point locations for different torque directions: for traction torque, the contact point is positioned to minimize sliding speed and maximize efficiency, while for overrun torque, the contact point is positioned below the root diameter to simplify design. This local optimization resolves the contradiction by allowing each torque direction to benefit from its optimal contact point location.
3Loss of energy
If thrust collar contact point is arranged close to pitch point, then efficiency is improved, but additional components are required increasing design complexity
Solution Approach 1:
The invention makes the thrust collar multi-functional by enabling it to handle both traction and overrun torques through radially offset contact surfaces. The first contact surface handles traction torque with high efficiency, while the second contact surface handles overrun torque with simplified design. This universality eliminates the need for separate components for each torque direction, resolving the efficiency-complexity contradiction.
4Device complexity
If single thrust collar is used for both traction and overrun torques, then component count is reduced, but acoustic performance deteriorates due to oscillations
Solution Approach 1:
The invention segments the thrust collar into two separate thrust collars, each dedicated to handling one torque direction. This segmentation eliminates the moving force-introduction point oscillations that occur when a single thrust collar handles both traction and overrun torques, thereby eliminating acoustic disturbances while maintaining reasonable component count through the integration of each thrust collar with its respective gearwheel.
Data Source
AI summary
A gear transmission includes a first helical-cut gearwheel (1) and a second helical-cut gearwheel (2) engaged for transmitting torques in different directions. The first gearwheel (1) and the second gearwheel (2) each include corresponding ring-shaped thrust collars (4, 5), and corresponding thrust collars (4, 5) each form a race (8, 9, 10, 11) having an overlap region. A first race (8) and a second race (9) form an overlap region for traction torques, and a third race (10) and a fourth race (11) form an overlap region for overrun torques. Each overlap region includes a contact surface or a contact point (14, 15), and each contact point (14, 15) is situated on a contact circle diameter (16, 17). The contact surfaces or contact points (8, 9) for traction torques and the contact surfaces or contact points (10, 11) for overrun torques are radially offset.