Injection molded blank for lead screw, rotor-blank assembly and method for producing same

1. A motor rotor-blank assembly for a motor ( 30 ), comprising:

a rotor ( 40 ) including a plurality of rotor anti-rotation features ( 44 ); and

a blank ( 10 ) having a hollow core ( 11 ) and including a plurality of blank anti-rotation features ( 14 ) corresponding to the rotor anti-rotation features ( 44 ),

wherein the rotor anti-rotation features ( 44 ) and the blank anti-rotation features ( 14 ) work in conjunction to maintain the blank ( 10 ) fixed within the rotor ( 40 ) during rotation of the rotor ( 40 ),

the rotor anti-rotation features ( 44 ) are bores through the rotor ( 40 ) in a direction substantia perpendicular to a longitudinal axis of the rotor ( 40 ) and the blank anti-rotation features ( 14 ) are protrusions situated around an outer circumference of the blank ( 10 ) to seat in the respective bores ( 44 ) through the rotor ( 40 ), and

the rotor ( 40 ) has a body ( 42 ) axially bounded by end collars ( 43 ), with internal diameter of the rotor body ( 42 ) larger than internal diameters of the end collars ( 43 ), to also restrain axial movement of the blank ( 10 ) within the rotor ( 40 ).

2. The motor rotor-blank assembly of claim 1 , wherein the blank anti-rotation features are produced from molding the blank within the rotor.

3. The motor rotor-blank assembly of claim 1 , wherein the blank is molded within the rotor.

4. The motor rotor-blank assembly of claim 3 , wherein the blank is injection molded within the rotor.

5. A linear actuator assembly, comprising:

a motor ( 30 ) including a rotor ( 40 ) having a plurality of rotor anti-rotation features ( 44 );

a blank ( 10 ) having a hollow core ( 11 ) and including a plurality of blank anti-rotation features ( 14 ) corresponding to the rotor anti-rotation features ( 44 ); and

wherein the rotor anti-rotation features ( 44 ) and the blank anti-rotation features ( 14 ) work in conjunction to maintain the blank ( 10 ) fixed within the rotor ( 40 ) during rotation of the rotor ( 40 ),

the rotor anti-rotation features ( 44 ) are bores through the rotor ( 40 ) in a direction substantially perpendicular to a longitudinal axis of the rotor ( 40 ) and the blank anti-rotation features ( 14 ) are protrusions situated around an outer circumference of the blank ( 10 ) to seat in the respective bores ( 44 ) through the rotor ( 40 ), and

the rotor ( 40 ) has a body ( 42 ) axially bounded by end collars ( 43 ), with internal diameter of the rotor body ( 42 ) lamer than internal diameters of the end collars ( 43 ), to also restrain axial movement of the blank ( 10 ) within the rotor ( 40 ).

6. The linear actuator according to claim 5 , further comprising a screw fixed within the blank.

7. The linear actuator according to claim 5 , wherein the blank anti-rotation features are produced from molding the blank within the rotor.

8. The motor rotor-blank assembly of claim 7 , wherein the blank is injection molded within the rotor.

9. A method for producing a rotor-blank assembly for a motor ( 30 ), comprising the steps of:

providing a rotor ( 40 ) with a plurality of rotor anti-rotation features ( 44 ); and

positioning a blank ( 10 ) within the rotor ( 40 ) to produce a blank ( 10 ) having a hollow core ( 11 ) and including a plurality of blank anti-rotation features ( 14 ) that correspond to the rotor anti-rotation features ( 44 ),

wherein the rotor anti-rotation features ( 44 ) and the blank anti-rotation features ( 14 ) work in conjunction to maintain the blank ( 10 ) fixed within the rotor during rotation of the rotor ( 40 ),

the rotor anti-rotation features ( 44 ) are bores through the rotor ( 40 ) in a direction substantially perpendicular to a longitudinal axis of the rotor ( 40 ) and the blank anti-rotation features ( 14 ) are protrusions situated around an outer circumference of the blank ( 10 ) to seat in the respective bores ( 44 ) through the rotor ( 40 ), and

the rotor ( 40 ) has a body ( 42 ) axially bounded by end collars ( 43 ), with internal diameter of the rotor body ( 42 ) larger than internal diameters of the end collars ( 43 ), to also restrain axial movement of the blank ( 10 ) within the rotor ( 40 ).

10. The method for producing a rotor-blank assembly for a motor of claim 9 , wherein the blank is positioned within the rotor using a molding process.

11. The method for producing a rotor-blank assembly for a motor of claim 9 , wherein the blank is injection molded into the rotor.

12. The method for producing a rotor-blank assembly for a motor of claim 9 , further comprising threading the blank to accept a screw.

13. The motor-rotor blank assembly of claim 1 , wherein external diameter of the rotor body ( 42 ) is also larger than external diameters of the end collars ( 43 ).

14. The motor-rotor blank assembly of claim 1 , wherein an inner surface of the hollow core ( 11 ) of the blank ( 10 ) is smooth or unthreaded.

15. The motor-rotor blank assembly of claim 1 , wherein

the rotor ( 40 ) comprises four bores ( 44 ) circumferentially arranged at approximately equidistant angles therethrough, and

the blank ( 10 ) comprises four protrusions ( 14 ) arranged at approximately equidistant angles around the outer circumference thereof.

16. The linear actuator according to claim 5 , wherein external diameter of the rotor body ( 42 ) is also larger than external diameters of the end collars ( 43 ).

17. The linear actuator according to claim 5 , wherein an inner surface of the hollow core ( 11 ) of the blank ( 10 ) is smooth or unthreaded.

18. The linear actuator according to claim 5 , wherein

the rotor ( 40 ) comprises four bores ( 44 ) circumferentially arranged at approximately equidistant angles therethrough, and

the blank ( 10 ) comprises four protrusions ( 14 ) arranged at approximately equidistant angles around the outer circumference thereof.