Electric motor, in particular for installation in a wheel body of a motorcycle

1 . An electric motor, comprising:

a liquid-cooled stator ( 1 ), including

a plurality of coils ( 10 ),

coil cores ( 12 ) inserted into the coils ( 10 ), and

a cooling body ( 14 ) accommodating the coils ( 10 ) in a form-fitting manner; and

a rotor ( 81 ) having permanent magnets ( 71 , 72 , 73 , 74 , 75 ) arranged on both sides of the liquid-cooled stator ( 1 ), the rotor ( 81 ) being of a double-sided axial flux machine design,

wherein the cooling body ( 14 ) includes a cooling core ( 16 ) with a plurality of cooling fins ( 41 ),

wherein the coils ( 10 ) are arranged between the cooling fins ( 41 ),

wherein radial channels ( 43 , 44 ) are formed in pairs side by side in the cooling fins ( 41 ), the radial channels ( 43 , 44 ) being connected to each other at radially outer ends of the cooling fins ( 41 ) by axial connection channels ( 46 ),

wherein the radial channels ( 43 , 44 ) at radially inner ends of the cooling fins ( 41 ) open into distributor channels ( 49 , 54 ),

wherein the distributor channels ( 49 , 54 ) are formed in a ring shape in the cooling core ( 16 ),

wherein multiple connection channels ( 57 , 58 , 59 ) are formed for each distributor channel ( 49 , 54 ) in the cooling core ( 16 ) to connect the respective distributor channel ( 49 , 54 ) to coolant lines ( 5 , 6 , 31 , 32 , 33 , 34 , 35 , 36 ) of a coolant distributor ( 110 ),

wherein the connection channels ( 57 , 58 , 59 ) are equidistantly spaced apart on the respective distributor channel ( 49 , 54 ) and open into the distributor channels ( 49 , 54 ), and

wherein the radial channels ( 43 , 44 ), the axial connection channels ( 46 ), and the distributor channels ( 49 , 54 ) are integrated as grooves into outside faces ( 3 , 4 ) of the cooling core ( 16 ).

2 . The electric motor according to claim 1 ,

wherein in the cooling core ( 16 ) for each of the distributor channels ( 49 , 54 ) exactly three of the connection channels ( 57 , 58 , 59 ) are formed for connecting a respective distributor channel ( 49 , 54 ) to coolant lines ( 5 , 6 , 31 , 32 , 33 , 34 , 35 , 36 ) of a coolant distributor ( 110 ).

3 . The electric motor according to claim 1 ,

wherein the connection channels ( 57 , 58 , 59 ) are spaced apart from each other at an angle of 120° on the distributor channels ( 49 , 54 ) and open into the distributor channels ( 49 , 54 ).

4 . The electric motor according to claim 1 ,

wherein the cooling core ( 16 ) has an inlet side and an outlet side next to each other in an axial direction,

wherein the radial channels ( 43 , 44 ) comprise

a left-side radial channel ( 43 ) arranged on a left side ( 3 ) and

a right-side radial channel ( 44 ) arranged on a right side ( 4 ), and

wherein the axial connection channels ( 46 ) are formed at the radially outer ends of the cooling fins ( 41 ) through which the left-side radial channels ( 43 ) and the right-side radial channels ( 44 ) are connected to each other in pairs.

5 . The electric motor according to claim 1 ,

wherein the cooling core ( 16 ) in an axial direction has an inlet side and an outlet side next to each other,

wherein the distributor channels ( 49 , 54 ) are formed side by side in the axial direction in the cooling core ( 16 ),

wherein the distributor channels ( 49 , 54 ) comprise a left-side distributor channel ( 49 ) arranged on a left side ( 3 ) and a right-side distributor channel ( 54 ) arranged on a right side ( 4 ).

6 . The electric motor according to claim 1 ,

wherein the cooling core ( 16 ) has a flow divider ( 47 , 52 ) in front of each of the radial channels ( 43 , 44 ) at a mouth of the radial channels ( 43 , 44 ) into the respective distributor channel ( 49 , 54 ).

7 . The electric motor according to claim 1 ,

wherein the coil cores ( 12 ) each consist of a bundle of electrically insulated wire segments arranged parallelly with a shaft ( 8 ) of the motor.

8 . The electric motor according to claim 1 ,

wherein the permanent magnets ( 71 , 72 , 73 , 74 , 75 ) are arranged in form of a Halbach array into magnet rings ( 70 , 84 ),

wherein a magnetic flux density of the magnet rings ( 70 , 84 ) on their side facing the coils ( 10 ) of the liquid-cooled stator ( 1 ) is greater than on their side facing away from the coils ( 10 ).

9 . The electric motor according to claim 1 ,

wherein the electric motor has axially protruding bearing bodies ( 97 , 98 ) relative to the rotor ( 81 ) for supporting a wheel on its shaft ( 8 ) bypassing the rotor ( 81 ),

wherein rotor bearings ( 93 , 94 ) are accommodated in the bearing bodies ( 97 , 98 ), the bearing bodies ( 97 , 98 ) are mounted on the shaft ( 8 ) by the rotor bearings ( 93 , 94 ), and

wherein the rotor ( 81 ) is bolted to and supported on the shaft ( 8 ) by the bearing bodies ( 97 , 98 ) and the rotor bearings ( 93 , 94 ).

10 . A wheel hub for a motorcycle comprising the electric motor according to claim 1 .

11 . A motorcycle, comprising

the electric motor according to claim 1 installed in

a rear wheel hub.

12 . The electric motor according to claim 1 ,

wherein the cooling body ( 14 ) is formed in multiple parts, the cooling body ( 14 ) having two cooling core covers ( 17 , 18 ) which are positioned on axially outward sides of the cooling core ( 16 ), and

wherein the distributor channels ( 49 , 54 ) and the radial channels ( 43 , 44 ) are grooves integrated into the cooling core ( 16 ) from axially outward sides of the cooling core ( 16 ) and covered by the cooling core covers ( 17 , 18 ).

13 . The electric motor according to claim 1 ,

wherein the electric motor has a two-part shaft ( 8 ) with shaft halves ( 23 , 24 ) including a left-side shaft half ( 23 ) and a right-side shaft half ( 24 ), and

wherein the left-side shaft half ( 23 ) is connected to the right-side shaft half ( 24 ) at a distance by shaft connectors ( 25 ).

14 . The electric motor according to claim 13 ,

wherein the shaft halves ( 23 , 24 ) have hollow bodies,

wherein the electric motor comprises a left-side shaft insert ( 27 ) inserted into the left-side shaft half ( 23 ) for axial passage of coolant through the left-side shaft half ( 23 ), and

wherein a right-side shaft insert ( 28 ) is inserted into the right-side shaft half ( 24 ) for passage of coolant through the right-side shaft half ( 24 ).

15 . The electric motor according to claim 13 ,

wherein the shaft halves ( 23 , 24 ) each have at least one cylindrical main section and an end section for connection to the shaft connectors ( 25 ),

wherein the end section is radially enlarged compared to the cylindrical main section, and

wherein the shaft connectors ( 25 ) are spaced apart parallel to each other and spaced apart from each other.

16 . The electric motor according to claim 12 ,

wherein the cooling body ( 14 ) has

retaining rings ( 19 , 20 ) enclosing windings of the coils ( 10 ) outwardly and

cooling fingers provided with retaining tabs ( 21 ).

17 . The electric motor according to claim 16 ,

wherein the retaining rings ( 19 , 20 ) are electrically insulated towards the cooling core covers ( 17 , 18 ).