Abstract: Improvements in previous bit assembly components including shortened slotted shanks and shortened base block bore receiving portions disclose relationships between shank differential interference portions and the corresponding base block bores. Changes in the differences in interference angles lead to changes in slot width, length and steel hardnesses in order to provide necessary retaining forces between the shank and base block bore.

Abstract: A bit holder and corresponding base block are disclosed wherein a slotted shank of the bit holder includes a reverse taper portion adjacent a distal end thereof. A base block with a bore for receiving said shank includes a corresponding hollow portion of reverse taper configuration that will tend to retain said shank therein.

Abstract: A quick change type bit/bit holder includes several different structures for holding the item in a bit block without the necessity of a fastener. The bit portion of the bit/bit holder combination includes a ductile steel insert with a polycrystalline diamond coated tungsten carbide bit positioned therein. The ductility of the steel insert acts as a shock absorber to allow the bit to successfully remove concrete as well as asphalt in a road milling machine.

Abstract: Bit holders and combination bit/bit holders with shortened quick change shanks that are selectably retainable in complementary base block bores that are likewise shortened for providing added spacing at the rear of base blocks. When a plurality of such base blocks are mounted in close proximity on a drum or endless chain, the added spacing provides ease of holder replacement and easy access at the rear of the bit holder base block bore.

Abstract: A quick change type bit/bit holder includes several different structures for holding the item in a bit block without the necessity of a fastener. The bit portion of the bit/bit holder combination includes a ductile steel insert with a polycrystalline diamond coated tungsten carbide bit positioned therein. The ductility of the steel insert acts as a shock absorber to allow the bit to successfully remove concrete as well as asphalt in a road milling machine.

Abstract: A quick change type bit/bit holder includes several different structures for holding the item in a bit block without the necessity of a fastener. The bit portion of the bit/bit holder combination includes a ductile steel insert with a polycrystalline diamond coated tungsten carbide bit positioned therein. The ductility of the steel insert acts as a shock absorber to allow the bit to successfully remove concrete as well as asphalt in a road milling machine.

Abstract: An improved diamond coated tip on a bit/holder for road milling operations has a broadened tip base that provides cutting overlap with adjacent bit/holders resulting in a micro milling type surface when utilizing a regular ? inch center-to-center drum. The ballistic insert of this design will cut asphalt as well as shallow depth concrete. Prior art design diamond tool can only cut asphalt. Tip breakage occurs when prior art diamond tool scratch concrete. Scratching concrete means engaging the top surface of concrete roadway.

Abstract: Improved bit holder/bit holder block structure provides increased access to the rear of the assembly allowing bit holder blocks to be mounted closer to each other for micro-milling operations. Shortened bit holder shanks are reconfigured from prior art to provide increased holding power between the bit holder shank and bit holder block bore.

Abstract: A quick change type bit/bit holder includes several different structures for holding the item in a bit block without the necessity of a fastener. The bit portion of the bit/bit holder combination includes a ductile steel insert with a polycrystalline diamond coated tungsten carbide bit positioned therein. The ductility of the steel insert acts as a shock absorber to allow the bit to successfully remove concrete as well as asphalt in a road milling machine.

Abstract: An improved bit holder includes a larger bit shank bore and an enlarged upper shank segment or band with a taper of up to 7 degrees per side that provides an interference fit between the top of the shank and top of the bit block bore when the bottom of the bit holder body seats on the top of the bit block bore. An annular tapered void adjacent the bit holder tire portion provides for ease of bit holder extraction.

Abstract: A quick change type bit/bit holder includes several different structures for holding the item in a bit block without the necessity of a fastener. The bit portion of the bit/bit holder combination includes a ductile steel insert with a polycrystalline diamond coated tungsten carbide bit positioned therein. The ductility of the steel insert acts as a shock absorber to allow the bit to successfully remove concrete as well as asphalt in a road milling machine.

Abstract: A plurality of differing horizontal pairs of slot shapes are positioned in the upper body portion of a quick change type bit holder to provide access to a bit extractor tool for removing the bit holder from its associated bit block.

Abstract: A bit holder for use in a bit assembly in road milling, mining and trenching equipment has a hollow generally cylindrical shank and first and second elongate slots positioned in spaced axial relation through the shank. The first slot extends along the shank to the distal end thereof. The second slot may be altered in length and/or shaped to fine tune the outward radial force the shank exerts against the bore of a bit holder block into which it is inserted.

Abstract: A quick change type bit holder for use in a bit assembly for road milling, road planing, trenching and mining equipment wherein a bit shank extends completely through an axially oriented bit holder bore includes a slotted shank having an outwardly tapered bit holder bore wherein insertion of the bit shank in a bit block acts to slightly collapse the shank which collapses the tapered bore to a generally cylindrical configuration that preferably snugly retains the bit shank rotatably therein.

Abstract: A plurality of differing horizontal pairs of slot shapes are positioned in the upper body portion of a quick change type bit holder to provide access to a bit extractor tool for removing the bit holder from its associated bit block.

Abstract: A quick-change tool holder has an enlarged forward end, a rearwardly extending shank, and an axial bore extending through the enlarged forward end and the shank with the bore having a diameter sized to receive the shank of a cutting tool. A second blind hole extends into the side surface of the enlarged forward end. An extraction device, such as the shank of a worn tool, is inserted into the blind hole. Where the extraction device is a worn tool, the cutting end of the tool is hit with a hammer to remove the tool from a base block mounting.

Abstract: A rotatable tool has a tool body that is generally symmetrical about a longitudinal axis, an enlarged cutting head, and a rearwardly extending shank. The shank joins the enlarged cutting head at an annular flange. A compressible sleeve is fitted around the shank and a wear ring is around the shank at the forward end of the sleeve. A disc spring is positioned between the radial flange and the sleeve to remove axial play between the shank and the sleeve and to seal the parts so that hard particles cannot enter and interfere with rotation of the tool.

Abstract: A retraction tool for removing the shank of a tool holder from a base block mounting includes an elongate threaded member having a hook threaded on one end thereof. The hook has a hook end for holding to the forward end of a tool holder. A hammer moveable along the length of the elongate member impacts against said stop for pulling said tool holder from said base block mounting.

Abstract: An improved bit assembly for road milling, mining and trenching equipment includes a streamlined tip assembly that is a combination of conical and cylindrical in shape and devoid of protrusions or annular indentations that might impede the flow of removed material over and around the bit assembly or provide space for removed material to become clogged or imbedded on the tip assembly. The generally cylindrical hollow shank that mounts the bit holder to the bit block includes at least one axially aligned slot along its side wall that allows the side wall to supply radial force to maintain the bit holder in the bit block.

Abstract: An improved bit holder with its mating bit block is disclosed utilizing a slight taper in the bit block bore, and a tapered shank on the bit holder that includes a second larger diameter tapered distal segment that combines with an axially oriented slot through the side wall of the bit holder shank to allow a substantially larger interference fit between the distal tapered shank segment and the bit block bore than previously known. When inserting the bit holder in the bit block bore, the distal first tapered segment resiliently collapses to allow insertion of that segment into the bit block bore. A second shank tapered portion axially inwardly of the first distal tapered portion. The dual tapered shank allows the insertion of the bit holder in the bit block with an interference fit that provides a secure mounting of the bit holder in the bit block.