Bit holder

Abstract

A unitary bit/holder and/or a bit holder including a body portion and a shank. The body portion and the shank being coaxial and including a bore extending from a forward end of the body portion to the distal end of the shank. The shank further including a segment adjacent a distal end of the shank that includes a plurality of ribs and at least one notch or relief zone between each rib in the plurality of ribs.

What is claimed is: 
     
       1. A bit holder comprising:
 a forward body portion having a bottom; 
 a generally cylindrical hollow shank depending axially from the bottom of the forward body portion, the shank comprising:
 a first segment adjacent a distal end of the shank, the first segment comprising a plurality of ribs solely around a first outer surface of the first segment; 
 a slot axially extending from the distal end of the shank to a slot termination disposed in a second segment adjacent the first segment, the second segment comprising a smooth second outer surface, a first diameter of the first segment subjacent the second segment greater than a second diameter of the second segment; and 
 a bore axially extending from a forward end of the forward body portion to the distal end of the shank, a portion of the bore internally adjacent the first segment, the portion including a smooth surface. 
 
 
     
     
       2. The bit holder of  claim 1 , further comprising:
 at least one notch disposed between each rib of the plurality of ribs. 
 
     
     
       3. The bit holder of  claim 2 , wherein the at least one notch is U-shaped. 
     
     
       4. The bit holder of  claim 2 , wherein the at least one notch includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of the bit holder. 
     
     
       5. The bit holder of  claim 1 , wherein each rib in the plurality of ribs includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of the bit holder. 
     
     
       6. The bit holder of  claim 1 , wherein the plurality of ribs is adapted to reduce a surface contact between the segment and a complementary portion of a bore of a base block and to provide a more evenly distributed and more highly concentrated force per segment. 
     
     
       7. A unitary bit/holder comprising:
 a forward body portion having a bottom; 
 a generally cylindrical hollow shank depending axially from the bottom of the forward body portion, the shank comprising:
 a first segment adjacent a distal end of the shank, the first segment comprising a plurality of ribs solely around a first outer surface of the first segment; 
 a slot axially extending from the distal end of the shank to a slot termination disposed in a second segment adjacent the first segment, the second segment comprising a smooth second outer surface, a first diameter of the first segment subjacent the second segment greater than a second diameter of the second segment; and 
 a bore axially extending from a forward end of the forward body portion to the distal end of the shank, a portion of the bore internally adjacent the first segment, the portion including a smooth surface. 
 
 
     
     
       8. The unitary bit/holder of  claim 7 , further comprising:
 at least one notch disposed between each rib of the plurality of ribs. 
 
     
     
       9. The unitary bit/holder of  claim 8 , wherein the at least one notch is U-shaped. 
     
     
       10. The unitary bit/holder of  claim 8 , wherein the at least one notch includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of the unitary bit/holder. 
     
     
       11. The unitary bit/holder of  claim 7 , wherein each rib in the plurality of ribs includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of the unitary bit/holder. 
     
     
       12. The unitary bit/holder of  claim 7 , wherein the plurality of ribs is adapted to reduce a surface contact between the segment and a complementary portion of a bore of a base block and to provide a more evenly distributed and more highly concentrated force per segment. 
     
     
       13. A combination for a bit assembly comprising:
 one of a unitary bit/holder and a bit holder comprising:
 a forward body portion having a bottom; 
 a generally cylindrical hollow shank depending axially from the bottom of the forward body portion, the shank comprising:
 a first segment adjacent a distal end of the shank, the first segment comprising a plurality of ribs solely around a first outer surface of the first segment; 
 a slot axially extending from the distal end of the shank to a slot termination disposed in a second segment adjacent the first segment, the second segment comprising a smooth second outer surface, a first diameter of the first segment subjacent the second segment greater than a second diameter of the second segment; 
 a shank bore axially extending from a forward end of the forward body portion to the distal end of the shank, a portion of the shank bore internally adjacent the first segment, the portion including a smooth surface; and 
 
 
 a base block comprising a base block bore adapted to make an interference contact with at least the first segment of the shank, the plurality of ribs adapted to reduce a surface contact between the first segment and a complementary portion of the base block bore of the base block and to provide a more evenly distributed and more highly concentrated force per segment. 
 
     
     
       14. The combination of  claim 13 , further comprising:
 at least one notch disposed between each rib of the plurality of ribs. 
 
     
     
       15. The combination of  claim 14 , wherein the at least one notch is U-shaped. 
     
     
       16. The combination of  claim 14 , wherein the at least one notch includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of at least one of the unitary bit/holder and the bit holder. 
     
     
       17. The combination of  claim 13 , wherein each rib in the plurality of ribs includes a pair of sides, each side disposed at at least one of an acute angle, an obtuse angle, and a right angle to a plane through a centerline of at least one of the unitary bit/holder and the bit holder.