Tool holder for a rotary hammer

Abstract

A tool holder for a hand-guided drilling device, in particular for a rotary hammer, includes a receiving sleeve that is designed as a single piece and that is drivable in a rotating manner for a shank part of an insertion tool. The recess is open at both end faces and limited therebetween by an inner circumferential surface of the receiving sleeve. The inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) includes at least six flat circumferential surface sections ( 62 n through 62 u; 84, 86 ) in the circumferential direction, with adjacent circumferential surface sections ( 62 n, 620; 62 p, 62 q; 62 r 62 s; 62 t, 62 u ) forming an angle of 120 degrees.

1 . A tool holder for a rotary hammer, comprising:
 a receiving sleeve formed as a single piece and that is drivable in a rotating manner, for a shank part of an insertion tool, a recess being open at both end faces and being bounded therebetween by an inner circumferential surface of the receiving sleeve,   wherein the inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) includes at least six flat circumferential surface sections ( 62   n  through  62   u;    84 ,  86 ) in the circumferential direction, with adjacent circumferential surface sections ( 62   n,    62   o;    62   p ,  62   q;    62   r    62   s;    62   t,    62   u ) forming an angle of 120 degrees, and wherein the inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) bounds at least one rotationally driving groove ( 66 ,  68 ) that is parallel to the rotation axis ( 64 ) of the receiving sleeve ( 34 ) for a shank part ( 16 ) with a circular cross section and at least one overhanging rotationally driving segment ( 28 ,  30 ).   
     
     
         2 . The tool holder as recited in  claim 1 , wherein the flat circumferential surface sections ( 62   n  through  62   u;    86 ) that are adjacent in the circumferential direction abut each other in pairs along apex lines ( 72 ), the angular separation between the apex lines ( 72 ) amounting to 60 degrees or a multiple of 60 degrees. 
     
     
         3 . The tool holder as recited in  claim 1 , wherein the flat circumferential surface sections ( 84 ) that are adjacent in the circumferential direction are separated from each other, the angular separation between their center lines amounting to 60 degrees or a multiple of 60 degrees. 
     
     
         4 . The tool holder as recited in  claim 1 , wherein the rotationally driving groove ( 66 ,  68 ) is bounded by two opposite, essentially parallel circumferential surface sections or flanks ( 62   g,    62   h,    62   i,    62   k ) and one circumferential surface section or groove base ( 62   l ,  62   m ) of the inner circumferential surface ( 62 ) that is essentially perpendicular to the circumferential surface sections or flanks ( 62   g,    62   h,    62   i,    62   k ). 
     
     
         5 . The tool holder as recited in  claim 1 , wherein the inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) includes several partially cylindrical circumferential surface sections ( 62   a  through  62   f ), the partially cylindrical circumferential surface sections ( 62   a,    62   b;    62   b,    62   c;    62   c,    62   d;    62   d,    62   e;    62   e,    62   f ) that are adjacent in the circumferential direction being separated by a pair of flat circumferential surface sections ( 62   n,    62   o;    62   p,    62   q;    62   r    62   s;    62   t,    62   u ) or by a rotationally driving groove ( 66 ,  68 ). 
     
     
         6 . The tool holder as recited in  claim 1 , wherein the inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) includes six rotationally driving ridges ( 80 ) for a shank part with a Torx profile that are parallel to the receiving sleeve ( 34 ) and are located at identical angular distances. 
     
     
         7 . The tool holder as recited in  claim 1 , further comprising a locking device ( 36 ,  38 ,  46 ,  50 ) for axially locking shank parts ( 12 ,  14 ,  16 )—which have different cross sections—of insertion tools ( 6 ,  8 ,  10 ) in the receiving sleeve ( 34 ). 
     
     
         8 . The tool holder as recited in  claim 7 , wherein the locking device ( 36 ,  38 ,  46 ,  50 ) includes a locking element ( 38 ) that reaches behind a corner ( 74 ) of a shank part ( 12 ,  14 ) with a hexagonal profile. 
     
     
         9 . A rotary hammer, comprising:
 a tool holder ( 2 ), said tool holder ( 2 ) comprising a receiving sleeve formed as a single piece and that is drivable in a rotating manner, for a shank part of an insertion tool, a recess being open at both end faces and being bounded therebetween by an inner circumferential surface of the receiving sleeve, wherein the inner circumferential surface ( 62 ) of the receiving sleeve ( 34 ) includes at least six flat circumferential surface sections ( 62   n  through  62   u;    84 ,  86 ) in the circumferential direction, with adjacent circumferential surface sections ( 62   n,    62   o;    62   p,    62   q;    62   r    62   s ;  62   t,    62   u ) forming an angle of 120 degrees.