Transmission-Mounted Resolver Layout for Work Vehicle Speed Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing work vehicles face challenges in detecting the rotation speed of motor generators at a low cost, requiring complex interlocking mechanisms and occupying significant space.
Innovation Solution
The integration of a resolver with a rotor fitted onto a rotary shaft and a stator supported by a transmission case wall allows for cost-effective rotation speed detection without additional interlocking mechanisms, utilizing a wall structure to support the stator and create cooling gaps, and efficient wire connection through a wire connector on the transmission case.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a special interlocking mechanism is provided to interlock the rotary shaft and the rotor, then the detection reliability is improved, but the device complexity and cost increase
Solution Approach 1:
The rotor is directly fitted onto the rotary shaft, merging the detection component with the drive shaft. This eliminates the need for separate interlocking mechanisms while maintaining reliable detection of rotation speed, thereby reducing device complexity and cost without sacrificing detection reliability
Solution Approach 2:
The rotary shaft serves dual functions: both as the drive shaft for the motor generator and as the mounting axis for the rotor. This multi-functionality eliminates the need for dedicated interlocking structures, simplifying the overall device design while ensuring reliable detection
2Temperature
If the resolver is positioned far from the wall, then the cooling effect is improved, but the space requirement increases
Solution Approach 1:
The resolver is positioned in the axial direction (along the shaft axis) rather than radially outward from the wall. This dimensional change allows the resolver to be cooled by air flow along the axial direction while maintaining a compact radial profile, thus achieving effective cooling without increasing the overall space requirement
3Temperature
If multiple supports are provided at dispersed locations, then the cooling effectiveness and workability are improved, but the manufacturing complexity increases
Solution Approach 1:
The support structure is divided into multiple discrete support protrusions at dispersed locations around the resolver. Each protrusion creates an independent cooling gap, enhancing overall cooling effectiveness while allowing modular manufacturing and assembly, thus improving workability without excessive manufacturing complexity
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 reduces space requirements, facilitates easy installation, enhances cooling, and simplifies the connection of electric wires, enabling low-cost and efficient rotation speed detection of motor generators.
Implementation Method 1
a resolver configured to detect a rotation speed of the motor generator, wherein the transmission is housed in a transmission case including a wall through which a rotary shaft of the motor generator is inserted, the resolver includes a rotor fitted onto the rotary shaft, and the resolver includes a stator supported by the wall
Data Source
AI summary
A rotation speed of a motor generator can be detected at a low cost in a work vehicle in which the motor generator is joined to a transmission that changes a speed of motive power from an engine for output to travel devices. A transmission case housing a transmission includes a wall through which rotary shafts of motor generators are inserted. Rotors of resolvers, which detect the rotation speed of the motor generators, are fitted onto the respective rotary shafts. Stators of the resolvers are supported by the wall.