Robot Joint Gear Structure for External Bevel Mesh Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing joint structures for robots face difficulties in meshing adjustment of bevel gears due to the motor being housed in the arm, making it challenging to attach and adjust gears without interfering with the arm's internal space.
Innovation Solution
A joint structure with a power transmission mechanism that includes positionally adjustable gears and a holder allowing for meshing adjustment outside the arm, using a first gear fixed to a shaft and a second gear coaxially mounted on a reducer, with shims for precise positioning and adjustment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If bevel gears are used to transmit power from the motor to the arm, then power transmission is achieved, but meshing adjustment becomes difficult when the motor is housed inside the arm
Solution Approach 1:
The power transmission system is divided into separate modules: the motor housing, the arm housing, and intermediate gear components. This segmentation allows meshing adjustment to be performed on individual components before final assembly, solving the problem of difficult adjustment when the motor is housed inside the arm.
Solution Approach 2:
A motor housing is introduced as an intermediary component that contains the motor and its associated gears. This intermediary structure provides external access points for meshing adjustment while still enabling the motor to be effectively housed within the arm assembly, thus resolving the contradiction between power transmission and adjustability.
2Volume of moving object
If the motor is housed inside the arm, then space is saved, but access for meshing adjustment is restricted
Solution Approach 1:
The motor housing is designed as a nested structure that can be attached to the arm in a space-efficient manner. The motor housing itself contains nested compartments for the motor and gear mechanisms, allowing compact integration while maintaining external access ports for adjustment operations.
Solution Approach 2:
Meshing adjustment is performed as a preliminary action during the assembly process, before the motor housing is permanently fixed to the arm. This allows adjustment to be carried out when access is available, and then the structure is finalized to achieve compact integration, resolving the conflict between space saving and adjustment access.
3Power
If multiple gears are used for power transmission, then functionality is achieved, but component count increases
Solution Approach 1:
Multiple gear functions are merged into integrated assemblies within the motor housing. Instead of separate adjustable gears distributed throughout the arm, the design combines pinion gears, bevel gears, and idler gears into unified modules that can be adjusted as complete units, reducing the effective number of discrete components while maintaining full power transmission functionality.
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
Enables efficient meshing adjustment in a wide space outside the arm, improving workability, reducing component count, enhancing transmission efficiency, and miniaturizing the gearbox while maintaining wire integrity during arm rotation.
Implementation Method 1
a first gear that is fixed to the shaft, a second gear that is coaxially mounted on the reducer and that meshes with the first gear
Data Source
AI summary
A joint structure for a robot includes a hollow first member, a second member, and an actuator that relatively rotates the first member and the second member about a first axis. The actuator includes a motor that is housed in the first member and that rotates a shaft about a second axis intersecting the first axis. A reducer decelerates a rotation of the shaft to transmit the rotation to the second member, and a power transmission mechanism transmits power from the motor to the reducer. The power transmission mechanism includes a first gear fixed to the shaft, a second gear coaxially mounted on the reducer meshes with the first gear, and a holder mounts the first gear so as to be positionally adjustable in a direction along the second axis and mounts the second gear so as to be positionally adjustable in a direction along the first axis.