Kennametal Inc.

Phillip W Haga

Douglas Edward Bise

Ted Richard Massa

Gary John Condon

Stephen T Belsheim

Curnie A Dunn

James E Rutherford

Randall W Oianen

A center vacuum rotary drill bit including a rotary drill bit body and an insert. The bottom surface of the slot has a projecting key that cooperates with a depression keyway of the insert. Generally vertical sidewall surfaces of a depression keyway and vertical surfaces of a projection key provide mechanical resistance against lateral movement of the cutting insert. This mechanical resistance reduces displacement of the insert with respect to the bit body during brazing and thus a high quality, accurately aligned drill bit assembly is provided by applicants' invention. The depression keyway is designed so as to minimize the effect of the axial load on the insert by avoiding sharp corners which tend to amplify nominal stress and provides an insert of a proper carbide density after pressing. Integral bit body protuberance means adequately separate the insert within the slot and permit braze flow between the insert and slot. The protuberance means enhance braze flow when braze is fed between the insert body and bit body.

Roof bit and insert assembly

Fluid roof bits for mining typically supply high pressure water to a location immediately adjacent the cutting insert of the roof bit to flush debris and cool the cutting insert. The present invention is a drill steel assembly for a wet roof bit that reduces the fluid pressure loss supplied to the roof bit. A drill head body is connected to the drill steel by an intermediate adaptor. The adaptor has a spring loaded button thereon that mates with an opening in the drill head body so that the drill head body can be conveniently snapped onto the drill head assembly. A bushing seal made from a flexible material is clamped between said drill steel adaptor and the drill head body to limit fluid pressure losses.

Liquid seal for wet roof bit

A rotary drill bit for penetrating earth strata wherein the drill bit includes a drill bit body that has an axial forward end. The drill bit body has a hard insert, which is preferably monolithic, that is affixed to the drill bit body at the axial forward end thereof. The hard insert presents at least three discrete leading cutting edges for cutting the earth strata. Each cutting edge is stepped.

Monolithic roof cutting bit insert

A center vacuum rotary drill bit including a rotary drill bit body and an insert. The bottom surface of the slot has a projecting key that cooperates with a depression keyway of the insert. Generally vertical sidewall surfaces of a depression keyway and vertical surfaces of a projection key provide mechanical resistance against lateral movement of the cutting insert. This mechanical resistance reduces displacement of the insert with respect to the bit body during brazing and thus a high quality, accurately aligned drill bit assembly is provided by applicants' invention. The depression keyway is designed so as to minimize the effect of the axial load on the insert by avoiding sharp corners which tend to amplify nominal stress and provides an insert of a proper carbide density after pressing. Integral bit body protuberances adequately separate the insert within the slot and permit braze flow between the insert and slot. The protuberances enhance braze flow when braze is fed between the insert body and bit body.

Roof bit body and insert assembly

A rotary drill bit for penetrating earth strata wherein the drill bit includes a drill bit body that has an axial forward end. The drill bit body has a hard insert, which is preferably monolithic, that is affixed to the drill bit body at the axial forward end thereof. The hard insert presents at least three discrete leading cutting edges for cutting the earth strata.

Drill bit, hard member, and bit body

A toolholder for securing a cutting tool used for mining and construction applications whereby the holder has a recessed groove to provide access to the underside of a flange on the cutting bit to promote removal of the cutting tool from the toolholder.

Cutting toolholder with recessed groove for cutting tool removal

A rotatable cutting bit for engaging earth strata wherein the bit comprises an elongate bit body rotatable about a central longitudinal axis. The elongate body has an axially forward end and an axially rearward end. A cutting insert is affixed to the elongate body at the axially forward end thereof. The cutting insert comprises a pair of top surfaces which intersect to form a chisel edge, and a pair of concave surfaces wherein each one of the concave surfaces is adjacent to and intersects its corresponding one of the top surfaces. The cutting insert further includes a pair of end surfaces and a pair of arcuate surfaces. One of the arcuate surfaces intersects the one top surface and further intersects the one end surface whereby the one arcuate surface joins the one top surface and the one end surface. The other of the arcuate surfaces intersects the other top surface and further intersects the other end surface whereby the other arcuate surface joins the other top surface and the other end surface.

Growing community of inventors

Chilhowie, VA, United States of America

Phillip W Haga