Provided is a production method, including a first preforming process, a second preforming process, and a finish forging process. In the first preforming process, while a plurality of flat parts are formed, a region to be a second pin is decentered. The second preforming process includes: a process of pressing each region to be a plurality of journals in a pressing direction corresponding to a width direction of the flat part by using a pair of second dies; and a process of, after starting the pressing by the second dies, decentering a region to be a first pin and to be disposed in a first position and a region to be a third pin and to be disposed in a third position from each other in opposite directions with a width direction of the flat part being as a decentering direction by using third dies.

The invention relates to a device for the impact treatment of transition radii (8) of a crank-shaft (4), in particular transition radii (8) between connecting rod bearing journals (5) and crank webs (7) and/or transition radii (8) between main bearing journals (6) and the crank webs (7) of the crankshaft (4). The device comprises an impact device (1) in order to introduce an impact force (FS) into at least one transition radius (8), wherein the impact device (1) has multiple impact heads (21) which are paired with the same transition radius (8).

The invention relates to a device for the impact treatment of transition radii (8) of a crank-shaft (4), in particular transition radii (8) between connecting rod bearing journals (5) and crank webs (7) and/or transition radii (8) between main bearing journals (6) and the crank webs (7) of the crankshaft (4). The device comprises an impact device (1) in order to introduce an impact force (FS) into at least one transition radius (8), wherein the impact device (1) has multiple impact heads (21) which are paired with the same transition radius (8).

A method for manufacturing a forged component includes: performing hot forging on a material; heating the hot forged material to a first set temperature; and performing warm coining to correctly shape the heated material. The material may be heated to a second set temperature before hot forging. The material heated to the second set temperature may be hot forged. The second set temperature may be higher than the first set temperature. The hot forged material may be subjected to controlled cooling to a third set temperature at a predetermined cooling rate. The controlled cooled material may be heated to the first set temperature. The third set temperature may be lower than or equal to the first set temperature.

A crankshaft (4) with a first central axis (A), has at least two main bearing journals (12), through which the first central axis (A) extends. At least one crankshaft web (10) is arranged between the main bearing journals (12), wherein the at least one crankshaft web (10) comprises two crank discs (14) connected with each other via a crankpin (16) with a second central axis (B). At least one crank disc (14) has a recess (26) with a planar bottom surface (28), wherein the recess (26) is adapted in the at least one crank disc (14) in such a way that the second central axis (B) of the crankpin (16) cuts the planar bottom surface (28). That planar bottom surface (28) is oriented at a right angle in relation to the direction of the second central axis (B) of the crankpin (16). A bore (30) with a third central axis (C) extend through the planar bottom surface (28) of the recess (26), through the at least one crank disc (14), and into the at least one crankpin (16). Also, a combustion engine (2), a vehicle (1) and a method for manufacture of a crankshaft (4) are disclosed.

A crankshaft (4) with a first central axis (A), has at least two main bearing journals (12), through which the first central axis (A) extends. At least one crankshaft web (10) is arranged between the main bearing journals (12), wherein the at least one crankshaft web (10) comprises two crank discs (14) connected with each other via a crankpin (16) with a second central axis (B). At least one crank disc (14) has a recess (26) with a planar bottom surface (28), wherein the recess (26) is adapted in the at least one crank disc (14) in such a way that the second central axis (B) of the crankpin (16) cuts the planar bottom surface (28). That planar bottom surface (28) is oriented at a right angle in relation to the direction of the second central axis (B) of the crankpin (16). A bore (30) with a third central axis (C) extend through the planar bottom surface (28) of the recess (26), through the at least one crank disc (14), and into the at least one crankpin (16). Also, a combustion engine (2), a vehicle (1) and a method for manufacture of a crankshaft (4) are disclosed.

A forged crankshaft manufacturing apparatus processes a forged blank with no flash. The forged blank includes at least one rough crank arm having an excess portion protruding from an outer periphery of a side portion thereof. The manufacturing apparatus includes a first die and a second die paired with each other, a retaining device, and a moving device. The first die and the second die bend or crash the excess portion. The retaining device retains at least one of the rough journals or at least one of the rough pins such that a rough pin decentering direction is perpendicular to a reducing direction in which the first die and the second die apply force for reduction. The moving device supports the retaining device such that the retaining device is movable in the reducing direction.

A forged crankshaft manufacturing apparatus processes a forged blank with no flash. The forged blank includes at least one rough crank arm having an excess portion protruding from an outer periphery of a side portion thereof. The manufacturing apparatus includes a first die and a second die paired with each other, a retaining device, and a moving device. The first die and the second die bend or crash the excess portion. The retaining device retains at least one of the rough journals or at least one of the rough pins such that a rough pin decentering direction is perpendicular to a reducing direction in which the first die and the second die apply force for reduction. The moving device supports the retaining device such that the retaining device is movable in the reducing direction.

Provided is a production method, including a first preforming process, a second preforming process, and a finish forging process. In the first preforming process, while a plurality of flat parts are formed, a region to be a second pin is decentered. The second preforming process includes: a process of pressing each region to be a plurality of journals in a pressing direction corresponding to a width direction of the flat part by using a pair of second dies; and a process of, after starting the pressing by the second dies, decentering a region to be a first pin and to be disposed in a first position and a region to be a third pin and to be disposed in a third position from each other in opposite directions with a width direction of the flat part being as a decentering direction by using third dies.

Provided is a production method, including a first preforming process, a second preforming process, and a finish forging process. In the first preforming process, while a plurality of flat parts are formed, a region to be a second pin is decentered. The second preforming process includes: a process of pressing each region to be a plurality of journals in a pressing direction corresponding to a width direction of the flat part by using a pair of second dies; and a process of, after starting the pressing by the second dies, decentering a region to be a first pin and to be disposed in a first position and a region to be a third pin and to be disposed in a third position from each other in opposite directions with a width direction of the flat part being as a decentering direction by using third dies.