Ball screw, spindle nut and method for producing a spindle nut

1. A method for producing a metallic spindle nut ( 10 ) for a ball screw ( 12 ), comprising the following steps:

providing a substantially cylindrical workpiece ( 50 ) from metal, with a first end face ( 46 ) and a second end face ( 44 ) and also a lateral surface ( 14 ),

shaping the workpiece ( 50 ) by pressing in an axially symmetrical central opening ( 16 ) and by simultaneously pressing in at least one first ( 18 ) and one second ( 20 ) channel which are oriented axially in parallel into the lateral surface ( 14 ) of the workpiece ( 50 ), the central opening ( 16 ) and the channels ( 18 , 20 ) being open toward the first end face ( 46 ),

introducing an internal thread ( 34 ) into the central opening ( 16 ), and

forming at least the first channel ( 18 ) as a transfer channel by introducing at least two radially running through-openings ( 22 , 24 ) into said channel ( 18 ) that are adapted for receiving diverting inserts ( 26 , 28 ).

2. The method as claimed in claim 1 , wherein the second channel ( 20 ), when not formed as a transfer channel, is produced with a pressing-in depth in a longitudinal direction and a volume of shaped material substantially corresponding to that of the first channel ( 18 ).

3. The method as claimed in claim 1 , wherein the pressing in of the channels ( 18 , 20 ) terminates before the second end face, such that the channels ( 18 , 20 ) are closed toward the second end face ( 44 ).

4. The method as claimed in claim 1 , wherein the through-openings ( 22 , 24 ) are at least one of milled or bored.

5. The method as claimed in claim 1 , wherein the central opening ( 16 ) is pressed in through to the second end face ( 44 ).

6. The method as claimed in claim 1 , wherein the pressing in of the central opening ( 16 ) ends before reaching the second end face ( 44 ) and the method further comprises removing the second end face ( 44 ) by a material removal process after the pressing in operation, such that the central opening ( 16 ) is open toward a new second end face ( 30 ) produced thereby.

7. The method as claimed in claim 6 , wherein the first end face ( 46 ) is removed by material removal after the shaping operation, resulting in a new first end face ( 32 ) being produced.

8. The method as claimed in claim 7 , wherein the removal of the end faces ( 44 , 46 ) by material removal is performed by turning.

9. The method as claimed in claim 1 , further comprising forming axially parallel flattened portions ( 36 , 38 ) into the lateral surface ( 14 ) during the shaping of the workpiece ( 50 ).

10. The method as claimed in claim 1 , wherein the angular arrangement of the channels in the lateral surface is between 100° and 180° relative to a central longitudinal axis of the workpiece.

11. The method as claimed in claim 10 , wherein the angular arrangement of the channels in the lateral surface is substantially 120° or 180° relative to the central longitudinal axis of the workpiece.

12. The method as claimed in claim 1 , wherein the production steps “pressing in of the central opening” and “pressing in of a channel into the lateral surface” are carried out by cold forming.

13. A spindle nut ( 10 ) for a ball screw ( 12 ), produced by the method as claimed in claim 1 , wherein the spindle nut ( 10 ) has in the lateral surface ( 14 ) at least one pair of the axially parallel channels ( 18 , 20 ), which are open toward the end face ( 32 ) of the spindle nut ( 10 ) and at least one of which comprises a transfer channel.

14. A ball screw ( 12 ), comprising:

a spindle nut ( 10 ) as claimed in claim 13 ,

a spindle ( 40 ),

a multiplicity of balls ( 42 ),

at least two diverting inserts ( 26 , 28 ) in the at least one channel ( 18 ) formed as the transfer channel, and

at least one transfer channel covering.