Internal Combustion Engine Dynamo Secondary Air Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing generators face challenges in efficiently managing increased heat generation due to rising power demands, which affects the service life of components like the front rotor bearing and stator winding, necessitating improved cooling solutions.
Innovation Solution
The introduction of a secondary air inlet with openings on the housing casing, creating a secondary air path that complements the primary air path, enhances heat uptake and dissipation by directing cooler air radially to critical components, thereby improving cooling efficiency for the rotor and stator.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If power demands for the generator are increased, then the electrical energy output is improved, but heat generation increases and affects the service life of components
Solution Approach 1:
The air inlet system is segmented into two separate inlets: a primary air inlet (12) with openings in the rear side wall and a secondary air inlet (18) with openings in the housing casing. This segmentation allows independent control of cooling air paths - the primary path cools the rotor while the secondary path provides additional cooling for the stator and housing, enabling effective heat management at higher power levels
2Device complexity
If a single air inlet system is used, then the device complexity is kept low, but the cooling efficiency for multiple components is insufficient
Solution Approach 1:
The air inlet system is divided into two independent systems: primary air inlet (12) opening into the housing interior and secondary air inlet (18) opening into the housing casing. Each inlet serves specific cooling functions - primary for rotor cooling and secondary for stator and housing cooling - achieving comprehensive cooling without requiring complex integrated systems
Solution Approach 2:
The secondary air inlet (18) serves multiple functions simultaneously: it provides additional cooling air to the housing casing, cools the stator winding, and supplements the primary cooling system. This multi-functionality allows a single additional inlet structure to address multiple thermal management needs, improving reliability without proportionally increasing complexity
3Temperature
If cooling air is directed only through the primary air path, then the rotor cooling is improved, but the front rotor bearing and stator winding are insufficiently cooled
Solution Approach 1:
The cooling system is segmented into two independent air paths: the primary air path (16) that directs cooling air along the rotor for intensive rotor cooling, and the secondary air path (20) that directs cooling air through the housing casing to cool the stator winding and front rotor bearing. This segmentation ensures each critical component receives dedicated cooling attention
Solution Approach 2:
Different regions of the generator receive cooling air with different characteristics: the primary air path provides high-velocity cooling air directly to the rotor, while the secondary air inlet provides additional cooling air that travels through the housing casing to reach the stator and bearing regions. Each region receives cooling tailored to its specific thermal requirements, extending component service life
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 enhances heat management, particularly for the front rotor bearing and stator winding, by ensuring effective cooling and extending the generator's service life through improved thermal irradiation and protection against impurities.
Implementation Method 1
the impeller wheel rotates with the rotor and in doing so generates a partial vacuum at the outer side of the front side wall, in the region of the outlet openings. This partial vacuum then itself generates a primary air flow which enters the housing through the primary air inlet
Implementation Method 2
The primary air flow expediently flows around the rotor along the primary air path, as a result of which heat can be intensively carried away from the rotor
Implementation Method 3
a secondary air flow which enters the housing through the secondary air inlet, follows the secondary air path within the housing and exits the housing through the air outlet. the cooling effect, in particular for the front side wall and as a result, in particular, for the front rotor bearing, is improved
Implementation Method 4
During the operation of the generator, the conversion of mechanical work into electrical energy also generates heat
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The present invention relates to an electric generator (1), preferably dynamo, for an internal combustion engine, having a stator (2), a rotor (3), a housing (4) which has a housing casing (6), a front side wall (7) and a rear side wall (8), an outer rotationally fixed impeller wheel (9), a primary air inlet (12) which has a plurality of inlet openings (13) formed in the rear side wall (8), an air outlet (14) which has a plurality of outlet openings (15) formed in the front side wall (7), a primary air path (16) which leads inside the housing (4) from the primary air inlet (12) to the air outlet (14), wherein the rotating impeller wheel (9) generates, in the region of the outlet openings (15), a partial vacuum which generates the primary air flow (31) which enters the primary air inlet (12), follows the primary air path (16) and exits through the air outlet (14). Improved cooling is brought about by means of a secondary air inlet (18) which has a plurality of secondary inlet openings (19) formed in the housing casing (6), and by means of a secondary air path (20) which leads within the housing (4) from the secondary air inlet (18) to the air outlet (14), wherein the partial vacuum generated by the rotating impeller wheel (9) generates a secondary air flow (32) which enters through the secondary air inlet (18), follows the secondary air path (20) and exits through the air outlet (14).