Abstract: Apparatus for supporting a cutting bit having an extended shank on a rotatable cutting drum is provided. The support apparatus includes a bit holder having an upper body portion and a shank portion and a generally rectangular mounting base having rear, side and front members. The upper body of the bit holder includes a bore for receiving the cutting bit shank and upper rear abutment surfaces perpendicular to the bit axis. The shank of the bit holder has a lower rear abutment surface having horizontal and vertical areas and a threaded bore which extends into the shank intermediate the upper and lower abutment surfaces. The rear portion of the mounting base includes upper abutment surfaces perpendicular to the bit axis and a lower abutment surface having horizontal and vertical areas. A draw bolt passes through the rear portion of the mounting base and serves to draw the upper and lower abutment surfaces of the bit holder and mounting base, respectively, into engagement.

Abstract: Apparatus for supporting a cutting bit having an extended shank on a rotatable cutting drum is provided. The support apparatus includes a bit holder having an upper body portion and a shank portion and a generally rectangular mounting base having rear, side and front members. The upper body of the bit holder includes a bore for receiving the cutting bit shank and upper rear abutment surfaces perpendicular to the bit axis. The shank of the bit holder has a lower rear abutment surface parallel to the bit axis and a threaded bore which extends into the shank intermediate the upper and lower abutment surfaces. The rear portion of the mounting base includes upper abutment surfaces perpendicular to the bit axis and a lower abutment surface parallel to the bit axis. A draw bolt passes through the rear portion of the mounting base and serves to draw the upper and lower abutment surfaces of the bit holder and mounting base, respectively, into engagement.

Abstract: A cutter bit holding assembly is disclosed. The cutter bit assembly contains a cutter bit having a shank portion and a cutter bit holder having a socket for receiving the cutter bit shank portion. Also included is a rotary locking element which is associated with the cutter bit holder and a bore adjacent the socket. The bore runs in a direction parallel the direction in which the bit holder cuts. The locking element has an offset locking portion which cooperates with an indented locking surface on the bit shank. The rotary locking element is capable of being rotated completely out of the socket bore and out of engagement with the bit shank locking surface to permit the unencumbered removal or insertion of a bit. An elastomeric element inserted along part of the bore in the cutter bit holder is utilized to prevent rotation of the locking element out of engagement with the bit shank locking surface during operation of the cutting device.