Digging tooth and holder therefor

The combination of a non-rotatable dirt type excavating tooth and a support block therefor;

• said support block includes a cylindrical bore which rotatably receives a cylindrical shank of a prior art rotatable type rock bit in mounted relationship therewithin;
• said tooth has a cylindrical shank made complementary respective to the block bore so that said shank can be telescopingly received in a captured manner within the bore of said support block, thereby removably mounting said excavating tooth respective to the support block;
• said tooth includes a blade-like ground engaging member opposed to said shank;
• means forming a locking device at a medial part of the tooth and the forward end of the block by which the tooth is rendered non-rotatable respective to the block;
• said locking device includes abutment means having at least one sidewall that extends from attached relationship respective to said block and forms at least one inwardly directed shoulder;
• said locking device further includes abutment means on said tooth that extends from attached relationship respective to the tooth and forms a plurality of outwardly directed shoulders spaced from the bore of the holder and which forms an included obtuse angle therebetween, said shoulders are positioned perpendicularly respective to a radial line extending from the central longitudinal axis of the block bore, said locking device on the block includes a projection which extends forwardly of the block and slidably receives in a selective manner at least one tooth shoulder thereagainst, thereby preventing axial rotation of said tooth respective to said block.

An improved non-rotatable, dirt type excavating tooth for use in a support block having a cylindrical bore formed therein, said block bore is round in cross-section and can rotatably receive a rotatable type prior art bit;

• said excavating tooth has a cylindrical shank at one end thereof which is opposed to a ground engaging member at the other end thereof, said shank being made complementary respective to the support block bore, said shank is telescopingly received in a captured manner within the bore of the support block thereby removably mounting said excavating tooth respective to the support block;
• said excavating tooth includes a ground engaging blade member which forms the leading marginal end thereof;
• means forming an abutment member at a medial portion of the tooth defined by the area where the round shank is joined to the blade member;
• said abutment member is spaced from said axial bore and includes a plurality of shoulders having outwardly directed surfaces that define a segment of a polygon, the polygon has a center coinciding with the longitudinal axis of the shank;
• means on said block forming another abutment member which is spaced from said block bore and includes at least one shoulder formed forwardly of the entrance to the block bore and arranged to slidably engage in a selective manner either of the surfaces of said polygon, so that said tooth can be placed within said bore and oriented into one of several axial positions.

In an excavating machine having a plurality of tooth receiving support blocks mounted thereon for movement to thereby provide for an excavation operation when digging teeth are mounted to the blocks, each support block includes spaced outer wall surfaces, and a cylindrical bore for rotatably receiving a cylindrical shank of a prior art rotatable type bit;

• the combination of said support block with a non-rotatable dirt type excavating tooth;
• said excavating tooth includes a cylindrical shank at one end thereof made complementary respective to the block bore, said shank is round in cross-section and has a longitudinal axis, said shank is telescopingly received with the bore of said support block, thereby removably mounting said excavating tooth respective to said block;
• said tooth includes a blade-like ground engaging member at the other end thereof, and a male abutment means formed at a medial portion thereof which separates the blade member from the shank;
• a female abutment means formed on said block for engaging said male abutment means of said tooth and thereby preventing axial rotation of said tooth when the tooth shank is received within the block bore;
• said female abutment means is spaced from the block bore;
• said male abutment means is spaced from said shank and is in the form of a segment of a polygon having a center which lies along the longitudinal axis of said shank;
• said tooth can be removed from the block, axially rotated into one of a plurality of axial positions respective to the block, and mounted within the bore of the support block;
• thereby preventing axial rotation of said blade-like ground engaging member respective to said block.