Patent ID: 7338235

Claim:
An internal broach having broach cutting teeth for internally broaching final profiles ( 12 ), wherein each of the broach cutting teeth cut a chip which in total form a final bottom ( 14 ) and final profile flanks ( 15 , 16 ), of female serrations of a work piece ( 8 ), comprising a shank ( 1 ), which leads in a direction of broaching ( 22 ) and has a central longitudinal axis ( 9 ); and a toothed section ( 2 ) with several rows ( 6 ) of broach cutting teeth ( 21 a to 21 f ), the rows ( 6 ) being disposed successively counter to the direction of broaching ( 22 ); with successive broach cutting teeth ( 21 a to 21 f ) being allocated to each other for broaching a profile ( 12 ) of a depth; with each of all the broach cutting teeth ( 21 a to 21 f ) in the several rows of the toothed section having only one each of first and second sides respectively facing the final profile flanks and a bottom cutting blade ( 23 a to 23 f ) forming an edge on a bottom cutting blade relief surface ( 24 ) which edge extends as an arc of a circle between the first and second sides so that the cutting blade cuts over a full final profile width (b); wherein the circles are concentric; wherein the bottom cutting blades ( 23 a to 23 f ) of successive and associated broach cutting teeth ( 21 a to 21 f ) each cut the chip to a thickness corresponding to a pitch (a) between the broach cutting teeth ( 21 a to 21 f ) that lead in the direction of broaching ( 22 ) and forms the final bottom and a portion of the entire final profile flanks ( 15 , 16 ) corresponding to the thickness of the chip cut, and; wherein the first and second sides join the bottom-cutting-blade relief surface ( 24 ) and form first and second edges; wherein all of the first sides are guide flanks ( 26 a to 26 f ), lie within a same curved plane with the first edges being guide edges ( 27 a to 27 f ) without a cutting ability to form the allocated profile flank ( 15 ); wherein all of the second sides are relieved surfaces ( 29 a to 29 c ) which do not touch the profiled flank ( 16 ) that the second sides face and which each extend in its own curved plane over the entire height of the respective broach cutting teeth, wherein all of the second edges are relieved edges ( 28 a to 28 f ) without a cutting ability to form the allocated profile flank in the vicinity of the pitch (a), and wherein the broaching of the final profiles takes place exclusively by means of the bottom cutting blades.