Method of producing shafts
A method of producing shafts such as shafts used in a transmission, particularly for a motor vehicle, is provided. A shaft base body and at least one gearwheel, which is at least substantially finished separately from the shaft and subsequently is fixed to the shaft in such a way as to transmit torque available at the shaft or input torque by the gearwheel having a hollow hub body and being axially pressed onto a seat on the shaft base body so as to form a frictional connection which transmits the torque from the shaft to the gearwheel.
1. A method for producing a shaft main body, said method comprising:
providing a preform produced from a solid material by mass forming, said preform consisting of a first partial region and a second partial region, the first of partial region having a shape at least approximately the same as a final shape of a partial region of the shaft main body to be produced, and the second partial region having a material reserve axially adjoining said first partial region, said material reserve having a shorter axial extension than and a diameter at least equal to a maximum diameter of a remaining portion of the shaft main body to be produced; and
subjecting said material reserve to swaging to form said material reserve into the remaining portion of the shaft main body,
wherein said material reserve is formed into the remaining portion of said shaft main body by rotary swaging using at least one mandrel.
2. The method as recited in claim 1 , wherein said shaft main body has at least one gearwheel having a hollow hub body fixed on a seat on the shaft main body, said method further comprising axially pressing the gearwheel onto the seat on the shaft main body to form a friction-locked connection for directly transmitting torque between the gearwheel and the shaft.
3. The method as recited in claim 2 , wherein at least one functional area selected from the group consisting of bearing seats, gear teeth, bearing races, and gearwheel seats is finish machined on the shaft main body prior to axially pressing the gearwheel onto the gearwheel seat on the shaft main body.
4. The method as recited in claim 1 , wherein said preform is at least partially hollow.
5. The method as recited in claim 4 , wherein said preform has a closed section in an axial end area of the first partial region.
6. The method as recited in claim 5 , wherein said closed section is formed from a hollow body by rotary swaging.
7. The method as recited in claim 1 , wherein said preform is continuously hollow along the entire length thereof.
8. The method as recited in claim 1 , wherein said remaining portion of the shaft main body is initially hollow, and an axial end area of said remaining portion is closed at least liquid-tight by rotary swaging.
9. The method as recited in claim 1 , wherein at least one functional area on said shaft main body is brought at least approximately to finished dimension by rotary swaging, said at least one functional area being selected from the group consisting of bearing seats for mounting the shaft, areas for forming synchronization gearing, bearing races for roller bodies for mounting idlers, and hub seat areas for mounting axially pressed-on gearwheels.