Cooling system for a drive motor of an alternative fuel vehicle

A cooling system for a drive motor (1) of an alternative fuel vehicle, wherein said drive motor comprises a motor housing (2), a stator core (3) arranged in said motor housing, and a stator winding (4) arranged inside said stator core, wherein said stator core is formed by a lamination of first core punches (31) and second core punches (32), characterized in that,

• said cooling system comprises:
• a flow guiding configuration (5) positioned at the outer periphery of said stator core, forming a connected space by means of a hole or slot in the outer periphery of said stator core for directing a coolant flow at the outer periphery of said stator core to cool said stator core, said flow guiding configuration comprising alternately arranged diversion regions (51) and convergence regions (52), wherein said diversion regions are configured to divide a coolant flow path into multiple paths and said convergence regions are regions where the multiple paths meet;
• wherein said flow guiding configuration is formed by a lamination of said second core punches;
• wherein said second core punch is arranged with slots for forming said convergence regions, and with a tab arranged on said second core punch;
• wherein said tab extends in a circumferential direction and comprises a plurality of holes therein, said plurality of holes comprising a short hole (322) and a medium-length hole (323) for forming said diversion region;
• wherein a circumferential angle between adjacent said holes is a second circumferential angle α;
• wherein a circumferential angle of said medium-length hole is a fourth circumferential angle γ;
• one or more coolant inlets (8) arranged on said motor housing in connection with said convergence regions, for introducing the coolant from outside said cooling system to the outer periphery of said stator core,
• a flow guiding hood (6) mounted in said motor housing, extending away from said stator core from the end of said stator core for directing the coolant flow to the end of said stator winding to cool the end of said stator winding, wherein said flow guiding hood only covers a portion of the upper part of the winding end of said stator core along the vertical direction, and wherein said flow guiding hood extends a distance along the axial direction of said stator core less than the distance that said end of said stator winding extends along the axial direction of said stator core outside of said stator core, and
• a convergence port (9) positioned in the upper part of the end of said stator core along the vertical direction, wherein the convergence port is formed by a lamination of said first core punch (31) at the end of the stator core and is configured to receive coolant that has flowed through the flow guiding configuration and direct the coolant into said flow guiding hood, thereby creating a serial flow path in which coolant first cools the outer periphery of the stator core and subsequently cools the end of the stator winding.