Independent Pivot Shift Fingers for Manual Gearbox Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing automatically switched manual gearboxes require significant axial force and are cumbersome and imprecise due to the need for axial movement of shift fingers, often relying on pneumatic or hydraulic power for gear engagement and disengagement.
Innovation Solution
The operating device features separate and independently pivotable shift fingers associated with specific engagement elements, eliminating the need for axial movement, allowing for reduced force application and simplification of the gearbox operation, using a rotary shaft package with coaxial rotary shafts and radially protruding pivot elements, and a slide mechanism for gear selection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If axial movement of shift fingers is used for gear engagement, then gear changing can be achieved, but the operation becomes cumbersome and imprecise with large force requirements
Solution Approach 1:
The shift mechanism is segmented into separate shift fingers (102, 103, 104), each independently pivotable and associated with a specific engagement element. This segmentation eliminates the need for axial movement of the entire shift finger assembly, allowing individual fingers to be actuated with minimal force through simple pivoting motion about rotary shafts.
Solution Approach 2:
Instead of moving shift fingers axially to engage gears (conventional approach), the invention inverts the mechanism by using pivoting motion of shift fingers about rotary shafts. The engagement elements are designed with notches or yoke-like shoulders that are acted upon by the pivoting shift fingers, transforming the required motion from axial translation to rotational pivoting, thereby reducing force requirements.
2Power
If pneumatic or hydraulic power means are used for axial movement of shift fingers, then gear engagement is achieved, but the device complexity and configuration become complicated
Solution Approach 1:
The invention replaces complex pneumatic or hydraulic power transmission systems with a simpler mechanical pivoting mechanism. Shift fingers are connected to rotary shafts that can be pivoted by minimal torque, eliminating the need for high-force axial actuation systems. This substitution dramatically simplifies the power equipment configuration while maintaining effective gear engagement capability.
Solution Approach 2:
The shift mechanism utilizes dynamic pivoting motion rather than static axial positioning. The shift fingers are designed to pivot freely about rotary shafts, allowing smooth, low-force actuation through rotational degrees of freedom. This dynamic approach replaces the rigid, high-force axial movement requirements with flexible, low-torque pivoting action.
3Manufacturing precision
If shift fingers are moved axially for gear engagement, then engagement is achieved, but precision and smoothness of operation are reduced
Solution Approach 1:
By segmenting the shift mechanism into individually pivotable fingers, each finger can be precisely positioned and controlled for its specific engagement element. This segmentation allows for smoother, more precise operation compared to moving an entire axial assembly, as each finger can be actuated independently with exacting control over its pivoting motion.
Solution Approach 2:
The invention inverts the conventional axial movement approach by using pivoting motion. This inversion enables smoother operation because pivoting about a rotary shaft provides natural mechanical guidance and reduces friction compared to sliding axial movement. The precision is improved as the pivoting mechanism allows for controlled, incremental engagement movements.
Data Source
Figure 1
Figure 2~3
Figure 4~6
AI summary
The invention relates to an operating device for an automatically switched manual gearbox. The gearbox is provided with a movable engagement element for each gear. The operating device is provided with rotary shafts (101) and rotatable shift fingers (102, 103, 104) to move selected engagement elements. According to the invention, the shift finger means (102, 103, 104) comprise a number of separate shift fingers (102, 103, 104) each associated with a specific engagement element. Each shift finger (102, 103, 104) is adapted to being separately pivotable independently of the other shift fingers (102, 103, 104).