Abstract: Rotatable elements for use with earth-boring tools include a movable element and a stationary element. The rotatable element may include a void within the support structure and at least one pin protruding from the void through an exterior side of the support structure. The rotatable element may further include at least one aperture configured to provide a vent to the void. The rotatable element may be disposed at least partially within a cavity of the stationary element. The stationary element may further include a track configured to interact with the at least one pin.

Abstract: The invention relates to a bit holder for an earth working machine, in particular a surface miner, a road milling machine, or the like, having a holding projection that comprises a bit receptacle and/or carries a cutting element. In order to improve the operating reliability of an earth working machine, provision is made according to the present invention that the holding projection has, behind the cutting element or behind a receiving region of the bit receptacle in the tool advance direction, a wear protection element having a hard-material element in order to provide an emergency-mode property.

Abstract: A cutting bit assembly includes a block, a bit sleeve, and a seal. The block includes a first bore and a fluid passage. The fluid passage includes a first portion and a second portion in fluid communication with the first portion. The first portion is oriented obliquely with respect to the first bore, and the second portion extends at least partially around the perimeter of the first bore. The bit sleeve includes a shank, a flange, and a second bore extending through the shank and the flange. The shank is positioned within the first bore of the block such that a surface of the flange engages a first end surface of the block. The seal is positioned between the second portion of the fluid passage and the shank to prevent contact between a fluid in the fluid passage and the outer surface of the shank.

Abstract: An apparatus for the milling cutting of rock, minerals or other hard materials has a tool drum which is rotatably mounted on a drum carrier about a drum axis and on the peripheral shell surface of which are disposed, in distributed arrangement, a plurality of tool carriers, which carry cutting tools and can be rotatingly driven, where their shaft axes run transversely to the drum axis. A first group of tool carriers and a second group of tool carriers are provided, where the rotational direction of the first group is counter to the rotational direction of the second group, and the shaft axes of the tool carriers of the first group and of the second group are oriented at different setting angles relative to the radial direction of the tool drum.

Abstract: A method for driving tunnels, galleries, shafts or the like with a driving device (1; 2; 15), including: that a cutting head (4) rotating around a general axis of rotation (R) and having cutting elements directed essentially radially outwardly is applied against a rock surface to be worked. The rock cutting elements (13), are formed on cutting rolls (7) are brought to roll against the rock side during pressing against the rock and rotation of the cutting head (4), and the rock cutting elements during rolling are brought to cut sidewardly arranged grooves in the rock surface at a distance from each other. The invention also concerns a rotatable cutting head and a device and a rig for driving tunnels, galleries, shafts or the like.

Abstract: In one aspect of the present invention, a tool has a wear-resistant steel base comprising a shank suitable for attachment to a driving mechanism. A planar end of a cemented metal carbide segment brazed to an interfacial surface of the base axially opposed to the shank. At least one interruption is formed in the interfacial surface.

Abstract: A cutting bit for use in a heavy-duty mining, drilling or milling operation includes a generally conical body, a first end of which presents a cutting point and a second end of which presents an axially extending recess. The body has a generally convex surface portion. Locking means releasably and rotatably connect the cutting bit to a protruding part of a bit holder. The recess has an entrance portion presenting a generally conical surface portion. A corresponding bit holder is presented as well as a system using the cutting bit and bit holder.

Abstract: A tip for a pick tool, comprising a polycrystalline diamond (PCD) structure joined to a substrate body. The PCD structure has a strike surface including an apex opposite a boundary with the substrate body. At least an outer volume of the PCD as structure contains filler material between diamond grains, the content of the filler material being more than 5 weight percent of the PCD material in the outer volume. The outer volume is proximate at least an area of the strike surface including the apex, and the thickness of the PCD structure between the apex and the boundary with the substrate body is at least 2.5 mm.

Abstract: The invention relates to a shank bit for a road milling machine or the like, having a bit head and a bit shank, the bit shank comprising a first cylindrical segment that is indirectly or directly adjacent to the bit head, and the bit shank comprising a second cylindrical segment that, facing away from the bit head, is indirectly or directly adjacent to the first cylindrical segment, and the diameter of the second cylindrical segment differing from the diameter of the first cylindrical segment. In a shank bit of this kind, improved utilization properties result from the fact that the first cylindrical segment has a diameter in the range between 18 mm and 30 mm, and an extent in the direction of the longitudinal center axis of the bit shank less than 30 mm.

Abstract: A pressure-compensated cutter assembly for a tunnel boring machine includes a shaft a cutter ring assembly rotatably mounted on the shaft, and first and second end retainers non-rotatably attached to the shaft. Rotary seal groups, immersed in lubricant, provide a moving seal between the rotating cutter ring assembly and the end retainers. A movable piston member is exposed to ambient pressures, and contacts the lubricant, such that increasing ambient pressure will increase the lubricant pressure, thereby keeping the pressure differential across the seal small. In one embodiment, the piston is a floating retainer portion. In another embodiment, the piston is an annular piston, and in another embodiment, the piston is a plurality of smaller pistons disposed in the first retainer.

Abstract: Apparatus, methods, and other embodiments associated with a mining and demolition tool are described herein. In an embodiment, a mining bit tool includes a mining and demolition bit tool base and a mining bit tool tip coupled to the mining bit tool base. The base includes a tapered portion and a stem. The tapered portion includes a first end and a second end, with a surface tapering from the first end to the second end. There are at least two flutes positioned along the tapered surface, where a first flute is positioned at an angle relative to a longitudinal axis passing through the center of the mining bit tool and a second flute is positioned to cross a path of the first flute. The stem extends from the first end of the tapered portion, and the tip is coupled to the second end of the tapered portion.

Abstract: A cutting tool assembly including a bit holder having a forward portion, a rearward portion, and a generally planar mounting surface between the forward and rearward portions. The forward portion defines a front aperture having an axis inclined relative to the mounting surface, and the rearward portion defines a rear aperture open to the front aperture. A cutting bit is mounted in the front aperture and includes a rearward end accessible through the rear aperture of the bit holder rearward portion.

Abstract: A cutting tool holding device includes a base, a cutting tool holder and a fastening member. The base includes an abutting portion and a transverse dovetail groove, wherein the abutting portion is defined between a first wall with a mounting surface and a second wall, and the transverse dovetail groove is formed on the mounting surface. The cutting tool holder has a transverse dovetail portion, wherein the cutting tool holder is abutted against the abutting portion, and the transverse dovetail portion is detachably engaged into the transverse dovetail groove on the mounting surface of the second wall. The fastening member is for fastening the cutting tool holder to the base.

Abstract: A rotatable grading pick has a head portion, a shank portion extending rearwardly from the head portion, and a polygonal portion on the rotatable grading pick. At least a portion of the outer perimeter of the polygonal portion can be engaged by a tool so that the polygonal portion can be rotated, and the shank portion can be rotated to clear debris between the shank portion and a retainer placed around a part of the shank portion.

Abstract: A cutting bit for use in a heavy-duty mining, drilling or milling operation includes a generally conical body, a first end of which presents a cutting point and a second end of which presents an axially extending recess. The body has a generally convex surface portion. Locking means releasably and rotatably connect the cutting bit to a protruding part of a bit holder. The recess has an entrance portion presenting a generally conical surface portion. A corresponding bit holder is presented as well as a system using the cutting bit and bit holder.

Abstract: A mounting for a replaceable tool on a ground-engaging machine, the mounting having a tool holder having an aperture extending into a body portion of the tool holder for receiving a projecting mounting portion of the tool, the tool holder having an inter-engagement structure for mechanically engaging with a base having a complementary structure, the base being adapted to be fixed to the machine, and the mounting further having retaining means for cooperating with the holder and the tool when installed to retain the holder on the base.

Abstract: A base block for a cutting drum is disclosed. The base block may have a first end. The first end may have an opening configured to receive a tool. The first end may also have a flat surface surrounding the opening. The base block may have a second end configured to abut the cutting drum. The base block may further have an internal passageway commencing at the opening configured to receive the tool. The passageway may define a longitudinal axis that is offset by an acute angle from being perpendicular to the flat surface.

Abstract: A roller drill for removing material, such as in particular rock, minerals or the like, according to the undercutting principle, comprising a cutting face which is formed concentrically around a central axis and widens conically toward an end face of the roller drill, and includes a supporting body which is arranged on the inner side of the cutting face and extends up to the end face of the tool. In order to provide a roller drill or a roller bit of which the tool life or service life is improved compared with the prior art, the cutting face is made of a harder material than the supporting body and the supporting body forms an annular web which is conical at least at an outer circumferential wall and which defines with its inner circumferential wall a free space at the end face of the tool. The tool can resharpen itself automatically due to the free space and the dissimilar material combination.

Abstract: A tool pick including a head portion, a larger diameter shoulder positioned rearwardly adjacent to the head portion and joined to the head portion at a junction, and a shank extending rearwardly with respect to the shoulder. Two or more fins extend generally radially outward from the head portion and the shoulder, each fin having an outer surface sloping outwardly and rearwardly from the head portion and a pair of side surfaces, a rear end of each fin being located rearward of the junction between the head portion and the shoulder, the fins defining a maximum diameter of at least about 105% of the diameter of the shoulder such that the outer surface of the fin at an axial position aligned with the junction is located radially outward with respect to the junction.

Abstract: In one aspect of the present invention, a degradation assembly comprises a pressing seal element and a pressurized rigid element disposed intermediate a rotating component and a stationary component. The rotating component comprising an impact tip bonded to an end opposing the stationary component. The seal element may energize the rigid element against one of the components to form a slidable seal capable of holding lubricant within the assembly and keeping debris out while still rotating.

Abstract: A cutting tool for use in impinging earth strata includes a cutting tool body having a head portion at an axial forward end, a collar portion axially rearward of the head portion, and a shank portion axially rearward of the collar portion at an axial rearward end, wherein the cutting tool body contains a first socket at the axial forward end thereof. The shank portion generally tapers in the axial rearward direction. The cutting tool also includes a hard cutting member affixed to the cutting tool body within the first socket. The hard cutting member includes an axial forward end and an axial rearward end. The hard cutting member also includes a superhard axial forward portion of the axial forward end thereof, wherein the superhard axial forward portion comprises a substrate and a layer of superhard material adhered to the substrate.

Abstract: A rotatable grading pick has a head portion, a shank portion extending rearwardly from the head portion, and a polygonal portion on the rotatable grading pick. At least a portion of the outer perimeter of the polygonal portion can be engaged by a tool so that the polygonal portion can be rotated, and the shank portion can be rotated to clear debris between the shank portion and a retainer placed around a part of the shank portion.

Abstract: A cutting tool body that includes an elongate steel body, which has an axial forward end and an axial rearward end. The elongate steel body contains at the axial forward end thereof a cold-headed socket. The cold-headed socket has an axial forward open end, an axial rearward closed surface, and a side socket surface extending between the axial forward open end and the axial rearward closed surface. The side socket surface contains an undercut adjacent the axial rearward closed surface.

Abstract: In one aspect of the invention, a degradation element includes a substrate bonded to a sintered polycrystalline ceramic. The sintered polycrystalline ceramic has a tapering shape and a rounded apex. The rounded apex has a curvature with a 0.050 to 0.150 inch radius when viewed from a direction normal to a central axis of the degradation element that intersects the curvature. The rounded apex includes the characteristic of when the rounded apex is loaded against a rock formation, the rounded apex fails the rock formation forming a crushed barrier ahead of the rounded apex that shields the rounded apex from a virgin portion of the rock formation while still allowing the rounded apex to penetrate below a surface of the rock formation.

Abstract: An assembly of a rotatable cutting tool and a tool holder is provided. The rotatable cutting tool includes a cutting tool body having a head portion at an axial forward end and a collar portion axially rearward of the head portion, and a shank portion axially rearward of the collar portion. Also included is a cap member positioned on the cutting tool body wherein the cap member has a base portion and a hard cutting tip affixed to the base portion. The tool holder includes a tool holder body containing a bore having a forward end and a rearward end. The rotatable cutting tool is rotatably retained in the bore of the tool holder body. In one aspect, the shank portion of the rotatable cutting tool is received in the bore of the tool holder body and means for lubricating the shank portion of the cutting tool body is provided. In another aspect, means for securing the cap member to the head portion is provided, for example magnetically securing the cap member to the head portion.

Abstract: A degradation assembly comprises a rotary portion and a stationary portion. The rotary portion includes a cemented metal bolster bonded to a tip. The tip comprises a asymmetric, substantially conically shaped tip formed of diamond and a cemented metal carbide substrate. The stationary portion comprises a holder configured to be coupled to a block mounted to a driving mechanism. A compressible element is disposed between and in mechanical contact with both the rotary portion and the stationary portion.

Abstract: A road grading pick includes a cutting head, a shank, a shoulder at a transition between the cutting head and the shank, and a polygonal-shaped washer or an oval-shaped washer. The shank is positioned in an opening of the washer to position the washer along a longitudinal length of the shank between a rearward end of the shank and the rearward facing surface of the shoulder. In a preinstalled position, the washer compresses a friction retainer on the shank of the road grading pick to facilitate seating of the road grading pick in a blade of a road grading apparatus. In an installed position on an adapter board for a moldboard of road grading equipment, the friction retainer is no longer in the opening of the washer and the washer prevents washer rotation and shields an underlying mounting surface while allowing rotation of the road grading pick.

Abstract: A rotatable cutting tool that is for impingement upon a substrate and adapted to be rotatably retained within the bore of a holder. The rotatable cutting tool includes an elongate cutting tool body, which has an axial forward end and an axial rearward end with a socket at the axial forward end thereof. The rotatable cutting tool further has a hard cutting member, which is affixed to the cutting tool body within the socket. The hard cutting member has an axial forward end and an axial rearward end. The hard cutting member has an axial forward functional portion which has a starting transverse functional dimension, and further has a base portion which has a maximum transverse base dimension. There is a ratio of the starting transverse functional dimension to the maximum transverse base dimension ranging between equal to 0.42 and less than 0.48.

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 having an annular inner portion contiguous with the forward end of the shank and an annular outer portion contiguous with the outer circumference of the enlarged cutting head. The annular flange is not planar. Instead, the annular inner portion of the flange is positioned axially forward of the annular outer portion.

Abstract: The invention relates to shank bit, in particular a road milling bit, having a carrier part (10) that comprises a shank (11), the shank (11) carrying a bit tip (18) made of hard material, the carrier part comprising, in the region between the shank and the bit tip, a receiving portion (14) on which a head part is held (30), and the head part comprising a circumferential chip discharge surface (34.1) tapering in a direction toward the bit tip. In order to enable a shank bit of this kind to be designed in wear-optimized fashion, the invention provides that the head part is held rotatably with respect to the carrier part.

Abstract: A rotatable cutting tool for use in impinging earth strata wherein the rotatable cutting tool includes a cutting tool body and a hard tip affixed to the cutting tool body. The cutting tool body includes a forward end for receiving the hard tip and a rearward end, a head portion, a collar portion, and a shank portion. In one aspect, the head portion includes a continuous arcuate outer surface providing a slim profile.

Abstract: A roller drill for removing material, such as in particular rock, minerals or the like, according to the undercutting principle, comprising a cutting face which is formed concentrically around a central axis and widens conically toward an end face of the roller drill, and includes a supporting body which is arranged on the inner side of the cutting face and extends up to the end face of the tool. In order to provide a roller drill or a roller bit of which the tool life or service life is improved compared with the prior art, the cutting face is made of a harder material than the supporting body and the supporting body forms an annular web which is conical at least at an outer circumferential wall and which defines with its inner circumferential wall a free space at the end face of the tool. The tool can resharpen itself automatically due to the free space and the dissimilar material combination.

Abstract: A cutting tool body that includes an elongate steel body, which has an axial forward end and an axial rearward end. The elongate steel body contains at the axial forward end thereof a cold-headed socket. The cold-headed socket has an axial forward open end, an axial rearward closed surface, and a side socket surface extending between the axial forward open end and the axial rearward closed surface. The side socket surface contains an undercut adjacent the axial rearward closed surface.

Abstract: Apparatus, methods, and other embodiments associated with a mining and demolition tool are described herein. In an embodiment, a mining bit tool includes a mining and demolition bit tool base and a mining bit tool tip coupled to the mining bit tool base. The base includes a tapered portion and a stem. The tapered portion includes a first end and a second end, with a surface tapering from the first end to the second end. There are at least two flutes positioned along the tapered surface, where a first flute is positioned at an angle relative to a longitudinal axis passing through the center of the mining bit tool and a second flute is positioned to cross a path of the first flute. The stem extends from the first end of the tapered portion, and the tip is coupled to the second end of the tapered portion.

Abstract: An apparatus for the milling and/or drilling cutting of materials, in particular for the removal of rock, minerals or coal, with a tool drum which is mounted on a drum carrier rotatably about a drum axis, in which a plurality of tool shafts, which carry cutting tools at their ends projecting from the tool drum, are rotatable drivable mounted, at least two of the tool shafts being drivable by a common gear drive which has power take-off gearwheels arranged fixedly in terms of rotation on the tool shafts, and a common drive element which cooperates with the power take-off gearwheels. The drive element and the tool drum being rotatable in relation to one another and the shaft axes of the tool shafts standing transversely to the drum axis.

Abstract: The present invention provides a holder for holding a tooth on a body of a cutting blade or grinding drum for cutting or grinding rock or hard earth formations. The body has an attachment surface for attaching the holder. The holder comprises a portion for holding the tooth in a manner such that a portion of the tooth projects from the holder. The holder also comprises a base surface for attaching the holder to the attachment surface of the body. The holder is positionable in a plurality of different orientations in which the base surface is attachable to the attachment surface and in which the received tooth projects from the body in a predetermined direction.

Abstract: A tool has a sintered body of diamond or diamond-like particles in a metal matrix bonded to a cemented metal carbide substrate at a non-planar interface. A working surface has at least one region fir enough away from the non-planar interface that during high pressure, high temperature processing a restricted amount of metal from the substrate reaches the region, the amount comprising 5 to 0.1 percent of the region by volume, resulting in the region having a high density of superhard particles.

Abstract: A mining machine includes a cutting mechanism with an arm, and a substantial weight of more than a thousand pounds attached to the arm. The mining machine also includes a first disc cutter adapted to engage the material to be mined and mounted on a first disc cutter assembly for eccentrically driving the first disc cutter, the first disc cutter assembly being mounted within the substantial weight. The mining machine also includes at least a second disc cutter spaced apart from the first disc cutter assembly and adapted to engage the material to be mined, and mounted on a second disc cutter assembly for eccentrically driving the second disc cutter, the second disc cutter assembly being mounted within the substantial weight.

Abstract: A cutting bit includes a body having a head and a shank, a cutting tip attached to a front surface of the head, the cutting tip including a base portion, an upper portion and a tip portion, and a cavity extending into an interior of the cutting tip a distance from a bottom surface of the base portion. The distance the cavity extends into the interior is such that a bottom of the cavity is axially closer to the tip portion than at least a portion of a skirt separating the base portion and the upper portion. The cutting tip is attached by both a mechanical connection and a joining process. An example of a mechanical connection is a post on the front surface of the head of the body inserted into the cavity of the cutting tip. A cutting tip per se, a cutting bit on a mining machine and a method of manufacturing of a cutting bit are also disclosed.

Abstract: A round shaft chisel with a clamping sleeve, wherein the round shaft chisel has a chisel head and a chisel shaft rotatably maintained in the clamping sleeve. A pivot bearing is between an inner contour of the clamping sleeve and a shaft contour of the chisel shaft so that a center longitudinal axis of the round shaft chisel is pivotably seated with respect to a center longitudinal axis of the clamping sleeve. As a result of the induced tumbling motion of the round shaft chisel within the clamping sleeve 30, improved dirt removal can be assured during operations. The improved rolling action results in reduced wear between the clamping sleeve and the chisel shaft, which has advantageous results regarding the service life.

Abstract: In one aspect of the invention, a degradation assembly comprises a holder. The holder is attached to a driving mechanism and comprises a longitudinal central bore. A pick comprises a body intermediate a shank and an impact tip, and the shank is disposed in the central bore of the holder. The impact tip comprises an impact surface diamond or cubic boron nitride. At least one rolling element is disposed intermediate an inner bore surface and the shank, and is adapted for low-friction rotation with respect to both the inner bore surface and the shank.

Abstract: In one aspect of the invention, a wear-resistant tool is disclosed which may comprise first and second cemented metal carbide segments chemically bonded together at an interface. The first segment may comprise a first coefficient of thermal expansion (CTE) at least at its interfacial surface and the second segment may comprise a second CTE at least at its interfacial surface less than the CTE of the first segment. The first segment may further comprise a cross-sectional thickness substantially equal to or greater than a cross-sectional thickness of the second segment at the interface.

Abstract: A rotatable cutting tool carried in a bore of a holder wherein the holder has a forward surface surrounding a forward end of the bore. The rotatable cutting tool includes an elongate cutting tool body that has a central longitudinal axis, an axial forward end and an axial rearward end. The cutting tool body contains a socket in the axial forward end thereof whereby the socket receives a hard insert therein. The cutting tool body has an enlarged diameter collar mediate of the axial forward end and the axial rearward end. The mediate collar presents an axial forward facing surface and an axial rearward facing surface. The cutting tool body has an axial forward hardness region beginning at and extending a first pre-selected distance in an axial rearward direction from the axial forward end to encompass the axial forward facing surface of the collar. The axial forward hardness region has a hardness equal to or greater than a first hardness, as well as a first average hardness.

Abstract: A rotatable cutting tool includes a cutting tool body that has an axial forward end and an axial rearward end. The cutting tool body further has an axial length. There is a hard tip, which has a distal end, affixed to the cutting tool body at the axial forward end thereof. The cutting tool body has a clearance portion axial rearward of the distal end of the hard tip wherein the clearance portion has a transverse dimension. The clearance portion includes an axial forward transverse dimension and a minimum transverse dimension that is axial rearward of the axial forward transverse dimension. The axial forward dimension is greater than the minimum transverse dimension. The clearance portion has an axial length equal to between about ten percent and about thirty-five percent of the axial length of the cutting tool body.

Abstract: A cutting tool body includes a net-shaped steel body that has an axial forward end and an axial rearward end. The net-shaped steel body contains at the axial forward end thereof a cold-headed socket. The net-shaped steel body further contains a cold-headed puller groove axial rearward of the cold-headed socket.

Abstract: A rotatable cutting tool carried in a bore of a holder wherein the holder has a forward surface surrounding a forward end of the bore. The rotatable cutting tool includes an elongate cutting tool body that has a central longitudinal axis, an axial forward end and an axial rearward end. The cutting tool body contains a socket in the axial forward end thereof whereby the socket receives a hard insert therein. The cutting tool body has an enlarged diameter collar mediate of the axial forward end and the axial rearward end. The mediate collar presents an axial forward facing surface and an axial rearward facing surface. The cutting tool body has an axial forward hardness region beginning at and extending a first pre-selected distance in an axial rearward direction from the axial forward end to encompass the axial forward facing surface of the collar. The axial forward hardness region has a hardness equal to or greater than a first hardness, as well as a first average hardness.

Abstract: In one aspect of the invention, an attack tool has a wear-resistant base suitable for attachment to a driving mechanism A first end of a generally frustoconical first cemented metal carbide segment bonded to the base. A second metal carbide segment is bonded to a second end of the first carbide segment at an interface opposite the base. The first end has a cross sectional thickness of about 0.250 to 0.750 inches and the second end has a cross sectional thickness of about 1 to 1.50 inches. The first cemented metal carbide segment also has a volume of 0.250 cubic inches to 0.600 cubic inches.

Abstract: A roller cutter includes a hub having crushing members mounted on an outer periphery thereof, and a shaft on which the hub is mounted for rotation. Opposite ends of the shaft include respective spigots. Seals are disposed adjacent respective ends of the shaft and are arranged radially between the shaft and the hub for preventing leakage of lubricant. Covers are disposed axially outwardly of respective seals for covering the respective seals. Each cover includes a generally radially inwardly directed projection received in an indentation formed in an outer surface of the shaft to lock the cover axially and rotationally with respect to the shaft.

Abstract: An arrangement for detecting the state of rotation of cutting rollers (2) of a shield tunneling machine has at least one cutting roller (2) comprising a generator unit (12) that generates electrical energy when the respective cutting roller (2) is rotating, a signal-generating unit (16) connected to the generator unit (12), and an antenna unit (17) connected to the signal-generating unit (16). The signal generating unit (16) serves to generate transmission signals characteristic of the state of rotation of the respective cutting roller (2). An antenna (20) of the antenna unit (17) is disposed over at least one outer circumferential portion of the respective cutting roller (2) and is equipped for the wireless transmission of the transmission signals. The arrangement further comprises a receiving unit equipped to receive the transmission signals and interpret them regarding the state of rotation of the respective cutting roller (2).

Abstract: Excavator drum for the production of vertical trenches, including a cylindrical shell (22) mounted so sa to rotate about its axis of revolution and a plurality of excavating tools (28, 30) mounted on the external face of the shell. The tools include a plurality of first rollers (36) equipped with cutting elements (38) mounted so as to rotate about axes, the mid-plane of the rollers substantially merging with the mid-plane (P-P?) of the shell, and the length of which is less the an the length of the shell; and a plurality of pairs of second rollers (50, 52) equipped with cutting elements, the rollers of the same pair being mounted so as to rotate about cantilever axles (54, 56) each roller having a length at least equal to the distance that separates one end a first roller from the corresponding end of the shell, the casing of the external end of the second rollers being at least in the plane containing one end (32, 34) of the shell.