Cross-Groove Constant Velocity Joint for Stable Cage Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fixed type constant velocity universal joints, particularly the six-ball crossing type, experience instability and torque loss at higher operating angles due to rotational forces applied to the cage, leading to reduced operability and efficiency in transmitting rotational power.
Innovation Solution
The six-ball fixed type constant velocity universal joint is designed with track grooves on the outer and inner joint members inclined between 8° and 16° with respect to the joint axial line, preventing wedge angles from becoming zero during rotation, thus stabilizing the cage and maintaining efficient torque transmission within normal operating angles of propeller shafts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the track grooves are formed with inclination directions opposite to each other in the crossing type configuration, then the cage is stabilized at the joint center and torque loss is suppressed, but at high operating angles the wedge angles become zero or reverse direction causing rotational force to be applied to the cage
Solution Approach 1:
The patent changes the geometric parameters of the track grooves by introducing an inclination angle α (5° ≤ α ≤ 15°) relative to the axial direction. This parameter modification ensures that the wedge angles formed by the track grooves remain positive throughout the rotation cycle, preventing the cage from being subjected to rotational forces while maintaining the stabilizing effect of the crossing type configuration.
2Power
If the wedge angles become zero or reverse direction during rotation, then the balls are released from holding positions but rotational force is applied to the cage causing instability, yet maintaining constant velocity transmission requires proper wedge angle formation
Solution Approach 1:
By modifying the track groove inclination angle α to be within 5° to 15°, the patent ensures that wedge angles remain positive during rotation, maintaining ball holding positions and preventing cage instability while enabling effective torque transmission.
Solution Approach 2:
The patent introduces asymmetric inclination of the track grooves relative to the axial direction, creating a specific geometric configuration where the grooves are inclined at angle α. This asymmetric design ensures that the wedge angles formed do not become zero or reverse, maintaining stable ball positioning and cage stability throughout the rotation cycle.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration effectively suppresses torque loss and heat generation, enhancing the joint's efficiency and durability while maintaining desired performance within the typical operating range of propeller shafts.
Implementation Method 1
track grooves on the outer and inner joint members inclined between 8° and 16° with respect to the joint axial line, preventing wedge angles from becoming zero during rotation
Data Source
Figure 1a
Figure 1b
Figure 2a
AI summary
Six track grooves (7) formed in a spherical inner peripheral surface (6) of an outer joint member (2) are each formed into an arc shape having a curvature center at a joint center (O) . The track grooves (7) are inclined in a circumferential direction of the outer joint member (2) with respect to a joint axial line (N-N), and are adjacent to each other in the circumferential direction with their inclination directions opposite to each other. Six track grooves (9) formed in a spherical outer peripheral surface (8) of an inner joint member (3) are formed so as to be mirror-image symmetrical with the track grooves (7) paired therewith of the outer joint member (2) with respect to a joint center plane (P) at an operating angle of 0°. An inclination angle (γ) of each of the track grooves (7) of the outer joint member (2) with respect to the joint axial line (N-N) is set to 8° or more and 16° or less.