Patent ID: 6140625
Filing Date: 2000-10-31
Classification: C21D,H05B,Y02P

Abstract:
A device for the rotary and simultaneous electroinductive hardening of bearing surfaces of crank pins of a crankshaft comprises a plurality of inductors, each of said inductors having first and second inductor branches,wherein said crank pins are disposed adjacent to each other on said crankshaft and offset in relation to one another in an axial direction of said crankshaft, wherein portions of said adjacent crank pins form an overlapping zone, and wherein edges of said adjacent crank pins opposite said overlapping zone form an edge zone,each of said inductors engaging about said crank pins by up to a maximum of 180.degree.,said first and second inductor branches being arranged in parallel to each other and following the curvature of said bearing surfaces of said crank pins,wherein said first inductor branch of a pair of said inductors is associated with said overlapping zone,wherein said second inductor branch of said pair of said inductors is associated with said edge zone,said first and second inductor branches include an increased distance A in said axial direction which is greater than half the total width of adjacent crank pins,wherein said pair of inductors engage around said crank pins from substantially the same direction, andwherein a zone of said increased distance A of said first and second inductor branches of a first of said pair of inductors is limited to a portion of said first inductor branch associated with said overlapping zone which does not, in any rotary position of said crankshaft, penetrate a corresponding portion of said first inductor branch of a second said pair of inductors.