Embodiments of the invention are directed to cutting tool assemblies, material-removing machines that include cutting tool assemblies, and methods of use and operation thereof. In some embodiments, the cutting tool assemblies described herein may be used in material-removing machines that may remove target material. For example, the cutting tool assemblies may include one or more superhard working surfaces and/or one or more shields.

Embodiments of the invention are directed to cutting tool assemblies, material-removing machines that include cutting tool assemblies, and methods of use and operation thereof. In some embodiments, the cutting tool assemblies described herein may be used in material-removing machines that may remove target material. For example, the cutting tool assemblies may include one or more superhard working surfaces and/or one or more shields.

Aspects of the present disclosure relate to an apparatus including a drum rotatable about an axis of rotation and a support mount secured to the drum. The apparatus includes a support mount defining first and second fastener openings and first and second anchor openings. A replaceable holding block mounts to the support mount and the replaceable holding block has a front face and a rear face. The replaceable holding block defines a first fastener opening, a second fastener opening, and a tooth opening that extend through the replaceable holding block from the front face to the rear face. The first and second fastener openings of the replaceable holding block align with the first and second fastener openings of the support mount when the replaceable housing block is mounted to the block mounting surface. A tooth is secured to the replaceable holding block at the tooth opening.

Aspects of the present disclosure relate to an apparatus including a drum rotatable about an axis of rotation and a support mount secured to the drum. The apparatus includes a support mount defining first and second fastener openings and first and second anchor openings. A replaceable holding block mounts to the support mount and the replaceable holding block has a front face and a rear face. The replaceable holding block defines a first fastener opening, a second fastener opening, and a tooth opening that extend through the replaceable holding block from the front face to the rear face. The first and second fastener openings of the replaceable holding block align with the first and second fastener openings of the support mount when the replaceable housing block is mounted to the block mounting surface. A tooth is secured to the replaceable holding block at the tooth opening.

Mineral bits (10, 100) and associated mounts (30, 116, 200) for use during excavation and mining operations are disclosed. An exemplary bit (10) has a front region (12) and an opposite rear region (14) and comprises a head portion (16) and a mounting portion (18) secured to the head portion (16). The mounting portion (18) can be configured to be releasably retained by a mount (30). A rounded transition (22) disposed in the front region (12) of the bit between the head portion (16) and the mounting portion (18) provides a clearance (C) between the head portion (16) and the mount (16). Mineral bits (10, 100) disclosed can be inserted into and withdrawn from mounts (30, 1 16, 200) by linear and/or rotational movement.

The invention relates to a bit holder having an insertion projection and having a holding projection having a bit receptacle, the insertion projection comprising a bearing segment and the holding projection comprising a supporting segment. In order to allow the bit holder to be braced in permanent and stable fashion with respect to a base part, provision is made according to the present invention that the supporting segment and/or the bearing segment comprise two supporting surfaces and bearing surfaces, respectively, arranged at an angle to one another; and that the longitudinal center axis of the bit receptacle and the longitudinal axis of the insertion projection enclose an obtuse angle.

The invention relates to a bit holder having an insertion projection and having a holding projection having a bit receptacle, the insertion projection comprising a bearing segment and the holding projection comprising a supporting segment. In order to allow the bit holder to be braced in permanent and stable fashion with respect to a base part, provision is made according to the present invention that the supporting segment and/or the bearing segment comprise two supporting surfaces and bearing surfaces, respectively, arranged at an angle to one another; and that the longitudinal center axis of the bit receptacle and the longitudinal axis of the insertion projection enclose an obtuse angle.

Mineral bits (10, 100) and associated mounts (30, 116, 200) for use during excavation and mining operations are disclosed. An exemplary bit (10) has a front region (12) and an opposite rear region (14) and comprises a head portion (16) and a mounting portion (18) secured to the head portion (16). The mounting portion (18) can be configured to be releasably retained by a mount (30). A rounded transition (22) disposed in the front region (12) of the bit between the head portion (16) and the mounting portion (18) provides a clearance (C) between the head portion (16) and the mount (16). Mineral bits (10, 100) disclosed can be inserted into and withdrawn from mounts (30, 116, 200) by linear and/or rotational movement.

The invention relates to a bit holder for an earth working machine, in particular a road milling machine, having a support body onto which a holding portion having a bit receptacle, and oppositely an insertion projection, are shaped. The holding portion is terminated at the end by a wear surface, and the bit receptacle by a centering receptacle opening in bevel fashion toward the wear surface. A centering height, measured in the direction of the longitudinal center axis, between an end of the centering receptacle and the wear surface or a maximum point of a projection projecting beyond the wear surface, is designed in such a way that the ratio between the inside diameter D.sub.i of the bit receptacle and the centering height is less than 8; and/or that the centering height is greater than an axial play of a round-shank bit installable in the bit holder; and that the support body comprises, on its side facing away from the holding portion, at least two bearing surfaces that are at an angle to one another and form a bearing-surface pair.

Reduced wear on the holding portion and a reduced load on the insertion projection, and thus an extension of the service life of the bit holder, are achieved.

A cutting tool holding mechanism includes a base, a handle and a locking assembly. The base includes an abutting portion, a receiving bore, at least one limiting bore and at least one limiting hole. The limiting hole is disposed at the base and communicated with the limiting bore. The handle abutted against the base includes a sleeved portion and a plurality of positioning surfaces. The locking assembly includes a packing ring, a locking screw, a locking member and a guiding bolt. The locking member received inside the limiting bore includes a screwed hole and a guiding groove. The guiding groove disposed at one side of the locking member and is aligned with the limiting hole when the locking member is disposed inside the limiting bore. The guiding bolt is disposed in the limiting hole and is abutted against the guiding groove to inhibit the locking member from rotating.