Segmented Wheel Rim for Motor Cooling and Vibration Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle wheel assemblies with integrated electric motors and braking systems face challenges in manufacturing complexity, maintenance difficulty, and susceptibility to vibrations, leading to reduced efficiency and increased maintenance costs.
Innovation Solution
A wheel assembly design featuring a wheel rim divided into two separable parts, allowing for a larger motor diameter with improved cooling and reduced vibration transmission, along with a removable disc brake caliper and rotor connection to the wheel rim, facilitating easier maintenance and assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the motor is housed inside the wheel rim with radial support arrangement, then the motor is protected and integrated, but the motor cooling efficiency is reduced and assembly tolerances must be very tight
Solution Approach 1:
The wheel rim is divided into two separable parts: an outer part and an inner part. The motor is housed in the inner part which can be removed as a complete assembly from the outer part. This segmentation allows the motor to be integrated when needed while enabling easy removal for cooling maintenance or replacement without affecting the outer wheel structure.
Solution Approach 2:
The inner part of the wheel rim acts as an intermediary structure that houses the motor and can be selectively removed. This intermediary component provides a dedicated motor housing that can be optimized for cooling while maintaining the overall wheel structure integrity when assembled.
2Device complexity
If the wheel rim is made as a single piece, then the structure is simpler, but the motor diameter is limited and cooling space is reduced
Solution Approach 1:
The wheel rim is segmented into two parts that can be separated. The inner part contains the motor housing and can be designed with optimized geometry for maximum motor diameter and cooling space. The outer part contains the wheel well and tyre mounting features. This segmentation removes the geometric constraints that would exist in a single-piece design.
Solution Approach 2:
The design transitions from a two-dimensional cross-sectional constraint to a three-dimensional assembly solution. By separating the wheel rim into parts that assemble in the radial direction, the design achieves greater motor volume in the radial dimension while maintaining the overall wheel outer dimensions.
3Volume of moving object
If the brake disc and motor are centrally supported on the hub, then the assembly is compact, but maintenance becomes extremely complex requiring complete disassembly
Solution Approach 1:
The wheel rim is segmented into an outer part and an inner part that can be separated. The inner part contains the motor and can be removed as a complete assembly from the outer part while remaining attached to the hub. This allows maintenance personnel to access and service the motor, brake disc, and related components by simply removing the outer wheel rim, which is a routine operation, rather than requiring complete disassembly of the entire assembly.
Solution Approach 2:
The inner part containing the motor is extracted as a removable assembly from the outer wheel rim. This extraction provides access to the motor and brake components for maintenance while maintaining their compact central mounting on the hub during normal operation.
4Productivity
If the rotor is rigidly connected to the wheel rim, then the motor transmission is direct, but vibrations from the tyre are transmitted to the motor air gap
Solution Approach 1:
The wheel rim is segmented into an outer part and an inner part. The rotor is rigidly connected to the inner part, which can be removed as a complete assembly. This segmentation allows the rotor to maintain its rigid connection for efficient power transmission while enabling the inner part to be removed to isolate the motor from vibration sources during maintenance or replacement.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A wheel assembly (1) for a vehicle, uncommonly capable of a compact construction and ease of maintenance, comprises: - A wheel rim (2) suitable to rotate around an axis of rotation (a- a), defining an axial direction (A-A) parallel or coincident with said axis of rotation (a-a), an orthogonal radial direction (R-R), and a circumferential direction locally coincident with a tangential direction (T-T) orthogonal to the axial direction (A-A) and the radial direction (R-R), said wheel rim (2) having a radially outer side, or outer side (3), opposite the axis of rotation (a-a), and a radially inner side, or inner side (4), facing the axis of rotation (a-a), said rim being suitable to receive externally a tyre (5), and wherein said wheel rim forms internally a cylindrical chamber of the rim (54) delimited radially from said inner side (4); - a motor (306) comprising a rotor (307) and a stator (308); said rotor (307) being supported, free to rotate, on said stator (308); said stator being fixed to a stator support (120); said motor (306) being housed in the said cylindrical wheel rim chamber (54) of said wheel rim (2 ); - said rotor (307) is selectively, removably and rigidly connected to the inner side (4) of said wheel rim (2), avoiding the interposition of elastic members or damping members; - said assembly (1) also comprising a braking device (10), said device comprising a disc brake disc (11) having a radially outer edge (12) and a radially inner edge (13), said braking device (10) further comprising a disc brake caliper (14) selectively, removably and rigidly connected, directly or indirectly, to said stator support (120), said disk brake caliper (14) being placed with its active part (21) astride the inner edge (13) of said disc brake disc (ID; in which - said wheel rim (2) is made in two parts (15, 16) selectively and removably connected with each other to form a wheel rim body (17); and wherein - one of the two parts of said wheel rim (15) forms in a single piece at least one spoke (18) that protrudes radially towards the axis of rotation (a-a); and wherein - said disc (11) is connected with its outer edge (12) to said at least one spoke (18).