Patent Description:
Mining machines may include rotating cutting discs to engage rock formations and walls cut or dislodge rock and/or mineral. The cutting disc may be rotated and driven to undercut the rock face at a narrow angle relative to the plane of the face, generating shear forces to cause the rock to fracture. Each cutting disc has a plurality of bits or buttons.

The document <CIT> discloses a cutting ring including segments coupled to a base roller body, and cutting elements provided on the segments.

The document <CIT> discloses a cutter assembly including cutting elements coupled to a cutter ring.

The document <CIT> discloses a rotary bit including two rows of inserts coupled to a disc.

The document <CIT> discloses chips coupled to a cutter ring.

The document <CIT> discloses a disc cutter including cutting inserts coupled to a body.

The document <CIT>discloses a mining machine with a driven disc cutter including a cutting disc. The mining machine comprises a platform, and an arm which pivots about an axis oriented substantially normal to a mine floor.

According to the present invention, a cutting device for engaging a rock face as defined by the features of claim <NUM>, and a cutting head for a mining machine as defined by the features of claim <NUM> are provided.

Further advantageous features of the invention e.g. are defined in the dependent claims.

Other features and aspects will become apparent by consideration of the following detailed description and accompanying drawings.

The use of "including," "comprising" or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms "mounted," "connected" and "coupled" are used broadly and encompass both direct and indirect mounting, connecting and coupling. Further, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings, and can include electrical or hydraulic connections or couplings, whether direct or indirect. Also, electronic communications and notifications may be performed using any known means including direct connections, wireless connections, etc..

<FIG> illustrates an exemplary mining machine <NUM> including a frame <NUM>, a boom <NUM>, and a cutting head <NUM> supported on the boom <NUM> for engaging a mine wall. The frame <NUM> includes a drive system including traction devices, such as tracks <NUM>, for moving the frame <NUM> over a support surface or mine floor. In the illustrated embodiment, the frame <NUM> further includes a gathering head <NUM> positioned adjacent the mine floor proximate the cutting head <NUM>. The gathering head <NUM> includes a deck <NUM> and rotating members <NUM> that direct cut material from the deck <NUM> onto a conveyor <NUM>. In some embodiments, the frame <NUM> may also include arms for directing cut material onto the deck <NUM>. In the illustrated embodiment, the mining machine <NUM> includes a single cutting head; in other embodiments, the machine <NUM> may include multiple cutting heads.

As shown in <FIG>, the cutting head <NUM> includes a cutting disc <NUM> having an outer edge or peripheral edge <NUM>, and the cutting disc <NUM> engages a mine wall (not shown) to remove rock from the wall. In the illustrated embodiment, the cutting head <NUM> further includes a carrier <NUM> and an arm <NUM>. The disc <NUM> is coupled to the carrier <NUM>, which is supported for rotation (e.g., by bearings <NUM> - <FIG>) relative to the arm <NUM> about an axis of rotation <NUM>. In the illustrated embodiment, the cutting disc <NUM> and/or carrier <NUM> are freely rotatable relative to the arm <NUM>. As shown in <FIG>, in the illustrated embodiment, the arm <NUM> includes a shaft <NUM> supporting the carrier <NUM>, and the cutting head <NUM> further includes an exciter assembly for inducing oscillation of the cutting head <NUM>. The exciter assembly includes an eccentric exciter mass <NUM> coupled to a shaft <NUM> and supported for rotation on the arm <NUM>, and a motor <NUM> for mechanically driving the exciter mass <NUM> to rotate. Rotation of the exciter mass <NUM> causes the cutting head <NUM> (including the cutting disc <NUM>) to oscillate.

In some embodiments, the cutting head and disc may operate in a manner similar to that of the mining machine disclosed in <CIT>. In other embodiments, the cutting head and disc operates in a similar manner to the cutting mechanism disclosed in <CIT>. In other embodiments, the cutting disc may be is driven to rotate in another manner.

As shown in <FIG> and <FIG>, the cutting disc <NUM> includes a main support <NUM> secured to the carrier <NUM>, and a cutting ring <NUM> extending around the main support <NUM>. The cutting ring <NUM> forms the peripheral edge <NUM> positioned within a plane <NUM> (<FIG>). In the illustrated embodiment, the peripheral edge <NUM> is formed at a junction between an end surface <NUM> (<FIG>) of the cutting ring <NUM> (e.g., a distal end of the disc <NUM>) and an outer lateral surface or peripheral surface <NUM> of the cutting ring <NUM>. In some embodiments, the plane <NUM> is coplanar with the end surface <NUM> of the cutting ring <NUM> and is perpendicular to the axis of rotation <NUM> (<FIG>) of the cutting disc <NUM>. The peripheral surface <NUM> may have a substantially cylindrical or frustoconical shape, and may extend around the axis of rotation <NUM>.

As shown in <FIG> and <FIG>, a plurality of cutting elements or cutting buttons or cutting bits <NUM> are positioned along the peripheral edge <NUM> and spaced apart from one another (e.g., at regular intervals). In the illustrated embodiment, the peripheral edge <NUM> includes a plurality of bores <NUM> (<FIG>), and each of the cutting bits <NUM> is positioned within an associated bore <NUM>. The main support <NUM> and/or the cutting ring <NUM> can be formed from rigid materials (e.g., steel and/or other metals), and the cutting bits <NUM> can be constructed from a material having high hardness (e.g., carbide).

Referring to <FIG>, in the illustrated embodiment, the cutting ring <NUM> may be formed as a plurality of radial cutting sections <NUM> independently and removably coupled to the main support <NUM> (e.g., by fasteners, quick release connections, etc.). Each of the cutting sections <NUM> supports some of the cutting bits <NUM>. In the illustrated embodiment, the cutting sections <NUM> are coupled to the main support <NUM> and positioned around the axis of rotation <NUM> (<FIG>), thereby defining a circular or round profile. In other embodiments, the cutting sections <NUM> may be positioned in a different manner. The detachable aspect of the cutting sections <NUM> provides a modular cutting disc <NUM>, allowing worn or degraded cutting sections <NUM> to be replaced individually without the need to replace the entire disc, reducing downtime due to maintenance. In other embodiments, however, the cutting ring <NUM> may be formed as a single unitary member supporting the cutting bits <NUM>.

As shown in <FIG> and <FIG>, each cutting bit <NUM> includes a first portion or base portion <NUM>, a second portion or transition portion <NUM>, and a third portion or cutting portion <NUM>. The base portion <NUM> includes a base end <NUM> defining a first end of the cutting bit <NUM>, and the cutting portion <NUM> includes a cutting tip or cutting edge <NUM> defining a second end of the cutting bit <NUM>. A longitudinal axis <NUM> extends between the base end <NUM> and the cutting edge <NUM>. In the illustrated embodiment, the base portion <NUM> has a cylindrical shape. The cumulative height of the base portion <NUM>, the transition portion <NUM>, and the cutting portion <NUM> defines a height H (<FIG>). In some embodiments, the height H is between approximately <NUM> and approximately <NUM>. In some embodiments, the height H is between approximately <NUM> and approximately <NUM>. In some embodiments, the height H is approximately <NUM>.

The base portion <NUM> is positioned within an associated bore <NUM> (<FIG>) of the cutting ring <NUM>. The base portion <NUM> includes an outer surface <NUM> having a width D2. The outer surface <NUM> is contiguous with a tapered base end <NUM> and the transition portion <NUM>. The transition portion <NUM> includes a tapered or inclined surface <NUM> extending outwardly from the outer surface <NUM> of the base portion <NUM>. The inclined surface <NUM> is contiguous with the base portion <NUM> and a shoulder <NUM>. The shoulder <NUM> has a width D1 that is wider than the width D2 of the outer surface <NUM>.

In the illustrated embodiment, the outer surface <NUM> and the shoulder <NUM> both have a circular profile, and the widths D <NUM> and D2 represent diameters of the respective portions. In some embodiments, the shoulder <NUM> has a diameter D1 between approximately <NUM> and approximately <NUM>. In some embodiments, the shoulder <NUM> has a diameter D1 of approximately <NUM>. In some embodiments, the outer surface <NUM> has a diameter D2 between approximately <NUM> and approximately <NUM>. In some embodiments, the outer surface <NUM> has a diameter D2 of approximately <NUM>. In other constructions, one or more of these widths may have different dimensions.

Referring now to <FIG>, in the illustrated embodiment, the cutting portion <NUM> includes a chisel shape. That is, the cutting portion <NUM> includes a pair of major chisel surfaces <NUM> extending from the shoulder <NUM> to the cutting edge <NUM>. The major chisel surfaces <NUM> are angled relative to each other and each major surface <NUM> forms an angle A relative to the longitudinal axis <NUM>. In some embodiments, the angle A is between approximately <NUM> degrees and approximately <NUM> degrees. In some embodiments, the angle A is approximately <NUM> degrees. As shown in <FIG>, the cutting portion <NUM> also includes a pair of minor surfaces <NUM> extending from the shoulder <NUM> to the cutting edge <NUM> on either side of the major chisel surfaces <NUM>. The minor surfaces <NUM> are angled relative to each other, and each minor surface <NUM> forms an angle B relative to the longitudinal axis <NUM>. In some embodiments, the angle B is between approximately <NUM> degrees and approximately <NUM> degrees. In some embodiments, the angle B is approximately <NUM> degrees. A transition between the major chisel surfaces <NUM> and the minor surfaces <NUM> may include a rounded or chamfered surface <NUM> (<FIG>). In other embodiments, the cutting portion may have a different geometry (e.g., conical, parabolic, ballistic, etc.).

As shown in <FIG>, each cutting bit <NUM> is received within an associated bore <NUM> of the peripheral edge <NUM>. In the illustrated embodiment, the base portion <NUM> and the transition portion <NUM> are received within the tapered bore <NUM>. The longitudinal axis <NUM> of the bit <NUM> may be oriented at an acute angle relative to the axis of rotation <NUM> (<FIG>) and/or relative to the end surface <NUM> of the cutting ring <NUM>. The cutting edges <NUM> of the cutting bits <NUM> may be positioned within a cutting plane.

As shown in <FIG>, in the illustrated embodiment, the inclined surface <NUM> of the transition portion <NUM> engages a corresponding tapered portion or countersink <NUM> in the tapered bore <NUM>, while the shoulder <NUM> and cutting portion <NUM> protrude from the bore <NUM> above the surface of the disc <NUM>. The cutting portions <NUM> of the bits <NUM> engage a rock face (not shown) during operation of the cutting head <NUM>. The engagement of the transition portion <NUM> and the countersink <NUM> provides a large surface area for distributing reaction loads exerted on the bits <NUM> and reducing bending stresses experienced by the bits <NUM>.

As shown in <FIG>, the cutting bits <NUM> are received within the bores <NUM> of the cutting disc <NUM>. The tapered geometry of the cutting bits <NUM> and the bores <NUM> reduces the necessary space needed between the cutting portions <NUM> of adjacent bits <NUM>, permitting adjacent bits <NUM> to be positioned close to one another and providing a high density of cutting bits <NUM> per unit of surface area along the peripheral edge <NUM> of the cutting disc <NUM>. The geometry also decreases the bending stresses on the cutting bits <NUM> to increase durability. In addition, the geometry of the bits <NUM> increases the surface area of the cutting portions <NUM> that engages the rock face during operation.

Claim 1:
A cutting device for engaging a rock face, the cutting device comprising:
a disc (<NUM>) supported for rotation about an axis of rotation (<NUM>), the disc (<NUM>) including a peripheral edge (<NUM>) extending around the axis of rotation (<NUM>); and
a plurality of cutting elements (<NUM>) secured to the disc (<NUM>), the plurality of cutting elements (<NUM>) spaced apart along the peripheral edge (<NUM>) of the disc (<NUM>) and positioned in a cutting plane (<NUM>), each of the cutting elements (<NUM>) including a base portion (<NUM>), a cutting portion (<NUM>) including a cutting edge (<NUM>), and a transition portion (<NUM>) extending between the base portion (<NUM>) and the cutting portion (<NUM>), the transition portion (<NUM>) including a tapered surface (<NUM>), a width of the transition portion (<NUM>) proximate the cutting portion (<NUM>) being larger than a width of the transition portion (<NUM>) proximate the base portion (<NUM>),
wherein the cutting portion (<NUM>) has a width that is larger than a width of the base portion (<NUM>), and
wherein the base portion (<NUM>) of each cutting element (<NUM>) is received within an associated one of a plurality of bores (<NUM>) positioned on the peripheral edge (<NUM>), the cutting portion (<NUM>) protruding from the bore (<NUM>), the transition portion (<NUM>) engaging a tapered surface (<NUM>) extending around an opening of the bore (<NUM>),
wherein the peripheral edge (<NUM>) is formed at a junction between an end surface (<NUM>) of the disc (<NUM>) and a peripheral surface (<NUM>) of the disc (<NUM>) extending around the axis of rotation (<NUM>), the peripheral edge (<NUM>) having a circular profile.