An automotive shaft includes a journal having a crest-to-crest contact surface area defined by and between undercut regions of the shaft, an entirety of the crest-to-crest contact surface area being laser hardened to a depth no greater than 1 mm to form a layer that does not contain unhardened portions.

An automotive shaft includes a journal having a crest-to-crest contact surface area defined by and between undercut regions of the shaft, an entirety of the crest-to-crest contact surface area being laser hardened to a depth no greater than 1 mm to form a layer that does not contain unhardened portions.

A method of manufacturing a crankshaft having weight-reducing forged holes can achieve lightening and precise forming by additionally including a punching process of using an individual hydraulic press. The method includes steps of: heating a steel bar, performing busting such that the heated steel bar is disposed in a cavity of a mold to be produced as a first intermediate shape of a crankshaft, performing brokering such that the first intermediate shape is produced as a second intermediate shape, performing finishing such that the second intermediate shape is produced as a third intermediate shape, performing trimming such that the third intermediate shape is produced as a complete shape of the crankshaft by cutting portions other than the shape of the crankshaft, and performing punching such that holes are formed in the complete shape of the crankshaft.

A pump assembly for supplying negative pressure to a pneumatic brake booster, wherein the pump assembly has at least two elastic displacement elements which are moved by connecting rods, the connecting rods each being rotatably mounted on an eccentric element. The eccentric element has a bearing seat element and a force element. At least two eccentric elements are secured next to each other on a drive shaft that rotates about an axis of rotation and an interlocking anti-rotation device is provided that determines a defined angular position of the eccentric elements relative to each other about the axis of rotation. In order to improve the ease of assembly and simplify the manufacturability, the anti-rotation device is designed as shaped elements of the bearing seat element in such a way that they engage in each other in an interlocking manner when the eccentric elements are in a defined angular position relative to each other.

A pump assembly for supplying negative pressure to a pneumatic brake booster, wherein the pump assembly has at least two elastic displacement elements which are moved by connecting rods, the connecting rods each being rotatably mounted on an eccentric element. The eccentric element has a bearing seat element and a force element. At least two eccentric elements are secured next to each other on a drive shaft that rotates about an axis of rotation and an interlocking anti-rotation device is provided that determines a defined angular position of the eccentric elements relative to each other about the axis of rotation. In order to improve the ease of assembly and simplify the manufacturability, the anti-rotation device is designed as shaped elements of the bearing seat element in such a way that they engage in each other in an interlocking manner when the eccentric elements are in a defined angular position relative to each other.

In an electric motor-pump assembly, two working diaphragms, each delimiting a working chamber, are cyclically driven by a crank drive via connecting rods. The crank drive includes eccentrics for each connecting rod, which are placed on an axial bearing journal in the extension of an output shaft of an electric motor. In order to ensure a rotationally fixed connection between the eccentrics and the bearing journal to be produced and in order to ensure an angularly precise position of the two eccentrics, each of the eccentrics is connected to the bearing journal by a positively locking engagement.

A crankshaft includes journals that define a central axis of rotation; crank pins that are eccentric with respect to the journals; crank arms connecting the journals to the crank pins; and counterweights integrated with the crank arms. Each of the crank arms has recesses in a surface adjacent to the crank pin. The recesses are disposed inward of peripheral regions in both sides along an edge of the surface, and are disposed along the peripheral regions. The crankshaft has a reduced weight, an increased torsional rigidity and an increased flexural rigidity.

A crankshaft includes journals that define a central axis of rotation; crank pins that are eccentric with respect to the journals; crank arms connecting the journals to the crank pins; and counterweights integrated with the crank arms. Each of the crank arms has recesses in a surface adjacent to the crank pin. The recesses are disposed inward of peripheral regions in both sides along an edge of the surface, and are disposed along the peripheral regions. The crankshaft has a reduced weight, an increased torsional rigidity and an increased flexural rigidity.

A balance weight includes a main weight portion extending over a range defined by a circular-arc circumferential edge centered at a rotational shaft hole side and a pair of virtual end surfaces located on the circular-arc circumferential edge on both sides of the rotational shaft hole, a pair of extension weight portions extending from the pair of virtual end surfaces to an opposite circular-arc side of the rotational shaft hole from the circular-arc circumferential edge, the rotational shaft hole provided at the main weight portion so as to be located on a central side of the circular-arc circumferential edge, a crank shaft attachment protrusion, a crank shaft hole provided at the crank shaft attachment protrusion radially eccentrically with respect to the rotational shaft hole, and a pair of spaces formed between positions on both sides of the crank shaft attachment protrusion and the pair of extension weight portions, respectively.

A balance weight includes a main weight portion extending over a range defined by a circular-arc circumferential edge centered at a rotational shaft hole side and a pair of virtual end surfaces located on the circular-arc circumferential edge on both sides of the rotational shaft hole, a pair of extension weight portions extending from the pair of virtual end surfaces to an opposite circular-arc side of the rotational shaft hole from the circular-arc circumferential edge, the rotational shaft hole provided at the main weight portion so as to be located on a central side of the circular-arc circumferential edge, a crank shaft attachment protrusion, a crank shaft hole provided at the crank shaft attachment protrusion radially eccentrically with respect to the rotational shaft hole, and a pair of spaces formed between positions on both sides of the crank shaft attachment protrusion and the pair of extension weight portions, respectively.