Abstract: A drill string element for use in top hammer percussive drilling comprises first and second tubes coupled together by a cylindrical thread, and at least one impact-transmitting ord slidably disposed in the tubes. The rod(s) includes abutments which engage restrictions formed at remote ends of the tubes whereby the rod(s) can be removed only by unscrewing the tubes from one another. Remote ends of the tubes define male and female conical threads which enable the element to be connected to similar elements in the forming of a drill string. The conical threads are easier to unscrew than the cylindrical threads to avoid an accidental separation of the tubes of each element when that element is being unscrewed from another element.

Abstract: A drill bit of the percussion type includes a bit body of steel, a front portion of which is provided with at least one slot in which an insert is attached by brazing. Brazed between the insert and side walls of the slot are side plates which are of uniform thickness while being thinner than the insert. The side plates are formed of cemented carbide or a metal alloy with a coefficient of linear expansion which for temperatures below 500.degree. C. is substantially smaller than that of steel and the braze metal while being approximately the same as that of the insert.

Abstract: A drill for metal working comprises a drill body and a replaceable drill tip. The drill tip carries cutting elements and is releasably fastened to the drill body by means of fasteners which are provided on opposite sides of the centerline of the drill. A rear surface of the drill tip is provided with a central and at least partially conical, recess which is intended to receive a central tap extending forwardly from a mainly planar front surface of the drill body in order to center the drill tip in relation to the drill body. The tap engages the partially conical recess, and includes an elastic portion enabling the tap to yield axially.

Abstract: A guide bar for a chain saw with closed oil channels, arranged to lubricate the inside of the chain just before it starts sliding against the underside of the guidebar, as well as the supporting teeth of the nose sprocket just before the intermesh with the chain.

Abstract: A cam shaft tool for a slide type lathe. The invention generally comprises an improved adjustable tool wherein a plurality of holders each carrying a cutting insert is fixed to a main block via an adjustment block. The holder is radially adjustable relative to said adjustment block and axially relative to said main block. The invention also relates to a cutting insert holder for use in a cam shaft tool.

Abstract: A milling cutter for chip machining is equipped with adjustable cutting inserts. The milling cutter comprises a tool body having a plurality of peripheral recesses. Each recess is adapted to receive a cutting insert, a support element for defining a support surface against which the insert abuts, an adjustment element for adjusting the position of the cutting insert in a first direction, and a wedge for securing the insert. The adjustment element is threadedly connected to the support element for rotation relative thereto when adjusting the insert. The support element could also include a rotatable portion for adjusting the insert in a second direction.

Abstract: Sawblade for a powered saw with of the type in which two of the sawblades reciprocate side-by-side in a groove on the underside of the guidebar. A downward force from the guidebar is transmitted to a plurality of short longitudinally spaced ledge section projecting from the outer side faces of the sawblade. The ledges are formed by outwardly bent portions of the sawblade. The ledges can be slightly convex as viewed from the side.

Abstract: A rotary milling tool comprises a cutter body, a plurality of cassettes mounted in respective recesses formed around an outer periphery of the body, and a plurality of fasteners applying retaining forces to respective cassettes. Each retaining force comprises a radial inward component and a component directed opposite the direction of rotation of the body. The radial inward component wedges the cassette against first and second radially outwardly divergent walls of the recess. The other component wedges the cassette against the second wall and a third wall which are forwardly convergent.

Abstract: A chainsaw guidebar comprises an elongate guidebar body replaceably secured to a nose part. The guidebar body is provided with a central extension, the shape of which matches a corresponding forwardly tapering recess in the nose part. Portions of the nose part longitudinally overlap portions of the guidebar body.

Abstract: This invention relates to a cutting tool material with improved toughness behavior. The improved toughness behavior is obtained by using carefully selected reinforcing materials. The objectives of this invention are realized by simultaneously utilizing additives resulting in different toughenings mechanisms. By the simultaneous utilization of different toughening additives, synergistic effects occur giving the tool excellent material properties. The tool material of the present invention comprises reinforcing whisker additives of one dimensional single crystals with preferably different diameter and aspect ratios, two dimensional single crystals with different thickness and aspect ratios, and, in combination therewith, phase transformation additives such as ZrO.sub.2.

Abstract: The present invention relates to a cemented carbonitride alloy in which the toughness has been improved by the incorporation in the structure of whiskers of nitrides, carbides and/or carbonitrides of titanium, zirconium and/or hafnium.

Abstract: A mineral cutter pick and its pick box are secured together through a spigot and socket connection. Opposed end faces of the pick and holding device that surround the connection have laterally oppositely inclined surfaces at opposite sides of a central plane of the pick extending in the direction of cutting movement. These complementary inclined faces improve the load distribution between the pick and its locking device in use and can also be arranged to restrict the entry of foreign matter into the spigot and socket connection.

Abstract: The invention relates to a tool for chip removing machining and a blade therefor. The tool comprises a holder, an elongated blade and an insert. The holder is provided with an expandable securing part and a head having a longitudinally recess arranged to receive the blade. The blade has an insert site which receives the insert. The blade is provided to be wedged up in the holder in the longitudinal direction of the blade and in two directions perpendicular thereto.

Abstract: A sawchain designed for resharpening while it is idling around the drive sprocket has cutting links (16) on the left and right sides with depth gauges (10) and spade-shaped cutters (22) which between their front (12) and rear borders (14) have a fold (13) substantially perpendicular to the lengthwise direction of the sawchain with the concave side outwards away from the central plane, permitting the rear border (14) and the side edge (12) to contact the side walls of the kerf. The depth gauge (10) is placed so far forward on the cutter links (16) that the chip thickness (19) is sufficient when the sawchain is straight. The intermediate drivelinks (21) may be provided with raker teeth (17) located so far to the rear that they do not touch the bottom of the kerf when the chain is straight, but only loosen and convey the chips cut by the cutters (22) of the cutter links (16).

Abstract: A cutting insert for chip removing machining, preferably for milling, includes a rake face and a clearance face. A cutting edge is arranged at the line of intersection of those faces. The rake face comprises at least two adjacent, elongated ridges which extend along at least a part of the cutting edge. A first ridge connects to the cutting edge. A second of the ridges is arranged to become active after wear of the first ridge. The first ridge becomes worn to a substantial degree before the second ridge is activated.

Abstract: Sawblades for cutting materials containing abrasive grains or fibers with a power saw utilizing two reciprocating sawblades in contact with each other guided by a groove in a guidebar, all teeth on one blade pointing forwards and all teeth on the other blade pointing backwards. The teeth are located with unequal distances chosen so that two teeth on the first blade will not simultaneously be opposite two teeth on the other blade with the same distance as the teeth on the first blade.

Abstract: A drill for stack drilling comprises a drill body, a central cutting insert, and a peripheral cutting insert. The inserts have active cutting edges arranged such that the drill successively cuts radially outwardly from the center of the drill in order to avoid the formation of break-out slugs. The active cutting edge of the central insert has three cutting edge portions forming obtuse angles with one another. The radially innermost one of those cutting edge portions is shorter than each of the other two cutting edge portions.