An apparatus for cutting a trench is formed from a housing and a cutting assembly at least partially positioned within the housing. The cutting assembly has a cutting wheel and a plurality of teeth extending from the periphery of the cutting wheel. The cutting wheel features a plurality of layers of cylindrical profile in which at least two of the layers have profiles with different diametrical dimensions. At least some of the teeth are positioned on different layers. A trench is formed by placing the apparatus on a surface of the ground and pushing or pulling the apparatus while the cutting assembly is rotated. In one configuration, at least one layer having a profile of larger diametrical dimension is situated between a pair of layers having profiles of smaller diametrical dimension. In such configuration, the apparatus cuts a t-shaped trench.

The invention relates to an ejector unit, in particular for a road milling machine, having an ejector that is replaceably mounted on a carrier. In one aspect the ejector is curved in a scoop-like fashion. In another aspect the ejector is reversible upon the carrier to allow the ejector to be reversed after one wear surface is worn, thus presenting a new second wear surface.

A milling drum is disclosed for use with a cold planer. The milling drum may have a cylindrical body, a flighting plate affixed to an outer surface of the cylindrical body, a base block affixed to the fighting plate and having a first bore, a tool holder disposed in the first bore of the base block and having a second bore, a cutting tool disposed in the second bore of the tool holder, and a paddle affixed to the outer surface of the cylindrical body adjacent the fighting plate. The milling drum may further have a first transmitter coupled to the cutting tool, and a second transmitter coupled to the tool holder.

A cylindrical cutting system, a bit holder assembly, and machine for milling or scarifying road surfaces are disclosed. A bit holder is attachable to a milling platform, and includes an inward facing surface for engaging a corresponding mating surface of the milling platform. The inward facing surface of the bit holder and the mating surface include aligning fastener and pin openings. A fastener and a pin are inserted within the respective openings to couple the bit holder to the milling platform. The mating surface may define a part of a recess formed in the milling platform. A wear element may be disposed at the leading side of the bit holder. Multiple platforms may be coupled together with axially extended platform fasteners.

A bit holder that includes a front portion and a shank axially depending from the front portion. The front portion having an axial length that is less than the axial length of the shank. A combination bit holder and base block that includes the bit holder with the front portion having an axial length that is less than the axial length of the shank. The base block including a mounting portion and a device receiving portion, the device receiving portion including a length that is the same or less than a length of the mounting portion. The base block having a device receiving portion that includes a length shorter than a length of the mounting portion adapted to provide increased access to the rear of the bit assembly allowing the base 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 base block bore.

The self-propelled construction machine comprises a machine frame 2, supported by a chassis 1, which has wheels or tracks 1A, 1B. A milling drum 4 is arranged on the machine frame. The wheels or tracks and the milling drum are driven by a drive unit 8. A control unit 19 controls the drive unit 8 and a signal-receiving unit 18 detects at least one measurement variable M(t) which is characteristic of an operating state of the milling drum. The rotational speed of the milling drum is adapted, based on at least one measurement variable M(t), to the operating conditions of the construction machine in such a way that the milling drum is operated in a non-critical operating state. The adaptive open-loop control of the milling drum rotational speed allows the construction machine to be operated at an optimum operating point with respect to the milling drum rotational speed.

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.

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.

An improved diamond coated bit tip insert on a bit/holder, tool, and/or pick for road milling operations that includes a body including a tip and a base subjacent the tip, the tip including an overlay on an outer surface of the tip. The bit tip insert also includes at least one heat transfer bore extending from a distal end and/or bottom of the body to a bore termination adjacent the tip. The at least one bore of the bit tip insert is adapted to allow inward contraction when the overlay transfers heat into the base during operation.

Milling-drumless products, systems, manufactures, and methods for removing material, such as concrete or asphalt, and a system and method of assembling material removal (for example, grinding and/or cutting) blade elements, or blade elements and spacers, to fabricate a configuration that eliminates a need for a large milling drum are provided. The method allows the configuration to be adjusted easily in a field situation to most any material removal width by exchanging, adding or subtracting blade elements and/or spacers.