The United States of America As Represented by the Secretary of

David A Larson

Roger J Morrell

Ryan P Lundberg

Brian C Donnelly

Peter L Ruzzi

David Eckhardt

A double acting bit holder that permits bits held in it to be resharpened during cutting action to increase energy efficiency by reducing the amount of small chips produced. The holder consist of: a stationary base portion capable of being fixed to a cutter head of an excavation machine and having an integral extension therefrom with a bore hole therethrough to accommodate a pin shaft; a movable portion coextensive with the base having a pin shaft integrally extending therefrom that is insertable in the bore hole of the base member to permit the moveable portion to rotate about the axis of the pin shaft; a recess in the movable portion of the holder to accommodate a shank of a bit; and a biased spring disposed in adjoining openings in the base and moveable portions of the holder to permit the moveable portion to pivot around the pin shaft during cutting action of a bit fixed in a turret to allow front, mid and back positions of the bit during cutting to lessen creation of small chip amounts and resharpen the bit during excavation use.

Double acting bit holder

An impact assisted segmented cutterhead device is provided for cutting various surfaces from coal to granite. The device comprises a plurality of cutting bit segments deployed in side by side relationship to form a continuous cutting face and a plurality of impactors individually associated with respective cutting bit segments. An impactor rod of each impactor connects that impactor to the corresponding cutting bit segment. A plurality of shock mounts dampening the vibration from the associated impactor. Mounting brackets are used in mounting the cutterhead to a base machine.

Impact assisted segmented cutterhead

A concave drag bit cutter device and cutting method using such a concave cutter bit are provided which provide substantially increased efficiencies over conventional point attack bits. A number of different cutter bit shapes employing a concave cutting face can be used. The cutter bits are intended to replace the conventional point attack cutter bits and can be used in continuous mining machines, saw blades, auger drills, longwall shearers and the like, in cutting and mining operations.

Concave drag bit cutter device and method

A universal ripper miner used to cut, collect and transfer material from an underground mine working face includes a cutter head that is vertically movable in an arcuate cutting cycle by means of drive members, such as hydraulically actuated pistons. The cutter head may support a circular cutter bit having a circular cutting edge that may be indexed to incrementally expose a fresh cutting edge. An automatic indexing system is disclosed wherein indexing occurs by means of a worm gear and indexing lever mechanism. The invention also contemplates a bi-directional bit holder enabling cutting to occur in both the upstroke and the downstroke cutting cycle. Another feature of the invention discloses multiple bits arranged in an in-line, radially staggered pattern, or a side-by-side pattern to increase the mining capacity in each cutting cycle. An on-board resharpening system is also disclosed for resharpening the cutting edge at the end of cutting stroke position. The aforementioned improvement features may be used either singly, or in any proposed combination with each other.

Universal ripper miner

A universal ripper miner used to cut, collect, and transfer material from an underground mine working face. The cutter head has a single large cutting bit attached to its periphery and moves in an arcuate cutting motion in a cycle less than 270.degree.. At each cutting cycle the bit's depth of material penetration is initially zero, increases to its maximum depth at about midway, and decreases to zero depth as it exits. Drive members, such as hydraulically actuated pistons, provide for this movement of the head/bit. Constructed as part of the cutting head adjacent to the bit, a hopper-type member with a partially opened upper section acts to continuously collect and transfer cut material from the mine face. A mechanically or gravity actuated door is at the end of this hopper member remote from the cutting head allows the cut material to be transferred to a lower conventional material handling system. The cutter head and its mounted frame can be moved in a direction perpendicular to the direction of the cutting head during its cutting cycle to allow a new adjacent cutting cycle to be performed. Also, after a desired number of cycles have taken place, the frame and cutting head can be advanced into the mine working face by a third power source.

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Minneapolis, MN, United States of America

David A Larson