The present disclosure relates to a method for producing a profiled hollow shaft for a telescopic steering shaft of a motor vehicle. A hollow shaft to be machined and a roller forming head having at least one roller are provided. A groove is produced in the hollow shaft by moving the hollow shaft relative to the roller forming head. In order to provide an improved and less expensive method for producing a profiled hollow shaft for a telescopic steering shaft of a motor vehicle, the hollow shaft is moved relative to the roller forming head exclusively in the direction of the longitudinal axis of the hollow shaft. The disclsoure also relates to a steering shaft having rolling body raceways.

In a method for producing an extruded bearing journal, the bearing journal is extruded in an extrusion tool by means of at least one extrusion punch and, after the extrusion of the bearing journal, reworking of the bearing journal is performed in order to improve the cylindricity of the bearing journal at least over a section of the longitudinal extent of the bearing journal. During the reworking, the bearing journal is arranged, at least over a section of its longitudinal extent adjoining its free end, in a cavity that is delimited in a radial direction of the bearing journal by a wall surface surrounding the lateral surface of the bearing journal, and a reworking punch which is movable in the longitudinal direction of the bearing journal is moved toward the free end of the bearing journal and is pressed against the face surface of the bearing journal and, in this way, a plastic deformation of the bearing journal, with a flow of material of the bearing journal, is effected.

While the loading member supporting mechanism moves the loading member from the workpiece set state to the workpiece retracted state and returns to the workpiece set state again, the displacement drive unit and the rotation drive unit perform an operation of disposing the workpiece holding portion arranged at the processing position to the replacement position and an operation of disposing the workpiece holding portion disposed at the replacement position to the processing position in a trajectory in which the loading member does not interfere with the shoe.

While the loading member supporting mechanism moves the loading member from the workpiece set state to the workpiece retracted state and returns to the workpiece set state again, the displacement drive unit and the rotation drive unit perform an operation of disposing the workpiece holding portion arranged at the processing position to the replacement position and an operation of disposing the workpiece holding portion disposed at the replacement position to the processing position in a trajectory in which the loading member does not interfere with the shoe.

A thrust foil bearing includes a base plate including an insertion hole through which a rotating shaft is inserted and a support surface disposed around the insertion hole on one side of the insertion hole in an axial direction, and a back foil disposed on the support surface, in which the support surface has a plurality of inclined surfaces of which inclination angles inclined toward the other side of the base plate in the axial direction become shallower in order toward an outside of the insertion hole in a radial direction, and the back foil is divided into a plurality of divided regions in the radial direction by a slit, and the plurality of divided regions are supported by the plurality of inclined surfaces.

A bearing component composed of a chromium-molybdenum-vanadium alloyed tool steel is produced by a process that includes: (i) performing a first preheating within a temperature range of 600-650° C., (ii) performing a second preheating within a temperature range of 850-900° C., (iii) austenitizing in vacuum at 1000-1180° C. for 20-40 min, (iv) gas quenching at a minimum of 4-5 bar overpressure, and (v) tempering by performing either a double temper at 520-560° C. for 1.5-2.5 hours in each temper, or a triple temper at 520-560° C. for 0.5-1.5 hours in each temper. The steel alloy may be composed (in mass percent) of 1.32-1.45 C, 0.32-0.50 Si, 0.26-0.48 Mn, 4.0-4.85 Cr, 3.35-3.55 Mo, 3.55-3.85 V, 0-0.13 W, 0-0.20 Ni, 0-0.15 Cu, 0-0.8 Co, 0-0.03 P, and 0-0.03 S, the balance being iron and unavoidable impurities. Mo may be replaced with W or vice versa in a replacement ratio Mo:W of 1:2.

A bearing component composed of a chromium-molybdenum-vanadium alloyed tool steel is produced by a process that includes: (i) performing a first preheating within a temperature range of 600-650° C., (ii) performing a second preheating within a temperature range of 850-900° C., (iii) austenitizing in vacuum at 1000-1180° C. for 20-40 min, (iv) gas quenching at a minimum of 4-5 bar overpressure, and (v) tempering by performing either a double temper at 520-560° C. for 1.5-2.5 hours in each temper, or a triple temper at 520-560° C. for 0.5-1.5 hours in each temper. The steel alloy may be composed (in mass percent) of 1.32-1.45 C, 0.32-0.50 Si, 0.26-0.48 Mn, 4.0-4.85 Cr, 3.35-3.55 Mo, 3.55-3.85 V, 0-0.13 W, 0-0.20 Ni, 0-0.15 Cu, 0-0.8 Co, 0-0.03 P, and 0-0.03 S, the balance being iron and unavoidable impurities. Mo may be replaced with W or vice versa in a replacement ratio Mo:W of 1:2.

A hydraulic valve system has a valve housing, which has a first connection side and a second connection side. The valve housing has a through-hole for accommodating at least one piston. The valve housing has a third connection side with at least three hydraulic connections which are each connected to the through-hole via a line. The hydraulic valve system has a connection block with at least three hydraulic through-lines each extending from a first connection opening arranged on a housing side of the connection block to at least one second connection opening arranged on a hole pattern side opposite the housing side. Each of the at least three first connection openings is connected in a fluid-tight manner to one of the at least three hydraulic connections, and the second connection openings are arranged in a pre-defined hole pattern. A method for manufacturing a valve housing is also disclosed.

A hydraulic valve system has a valve housing, which has a first connection side and a second connection side. The valve housing has a through-hole for accommodating at least one piston. The valve housing has a third connection side with at least three hydraulic connections which are each connected to the through-hole via a line. The hydraulic valve system has a connection block with at least three hydraulic through-lines each extending from a first connection opening arranged on a housing side of the connection block to at least one second connection opening arranged on a hole pattern side opposite the housing side. Each of the at least three first connection openings is connected in a fluid-tight manner to one of the at least three hydraulic connections, and the second connection openings are arranged in a pre-defined hole pattern. A method for manufacturing a valve housing is also disclosed.

A method for producing a valve body of a hollow valve with optimised interior stem geometry includes a preform with a valve plate and a tubular wall surrounding a cavity. Flow forming the tubular wall over a flow-forming mandrel, which is inserted into the cavity to enlarge a length of the tubular wall. An interior area of the tubular wall is embossed with a structure either due to the fact that the flow-forming mandrel is a structuring mandrel having a surface structure, or alternatively, because the method includes a further step of reducing an outer diameter of the tubular wall by swaging or drawing and ironing over a structuring mandrel. Furthermore, a hollow valve is produced by this method.