Note: Descriptions are shown in the official language in which they were submitted.
CA 02992798 2018-01-17
WO 2017/012690
PCT/EP2016/001109
-1-
Description
CUTTING BIT CARRIER FOR CUTTING BITS
Technical Field
[01] The present disclosure generally relates to a cutting bit carrier for
supporting cutting bits used in underground mining applications. The present
disclosure further relates to a tool support for accommodating a plurality of
cutting bit carriers, a cutting head provided with a plurality tool supports,
and a
method for mounting a cutting bit to a cutting bit carrier. The present
disclosure
further relates to cutting bits used in underground mining applications for
extracting hard rock material.
Background
[02] In hard rock mining applications, it is common to use, for
example, rock shearers for winning hard rock materials in a longwall, or to
use,
for instance, rock headers for generating a roadway in an underground mine.
Both the rock shearer and the rock header may comprise at least one rotatable
drum, which may be equipped with at least one cutting head being rotatable.
The
cutting head may be configured to be provided with a plurality of cutting bits
which are in turn configured to engage the hard rock for extracting hard rock
materials. The rotatable drum may be adjustable in height relative to a
machine
frame by a swivel arm.
[03] The rotatable cutting head may include a cone-like shaped body
having cutting bit carriers integrally formed with the body. Thus, known
cutting
heads may be manufactured as an integral unit, wherein worn cutting bits may
be
replaced by newly manufactured cutting bits. The cutting bits are rotatably
and
removably supported by cutting bit carriers attached to the cutting head.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-2-
[04] A mineral cutter system is known from US 2009/0091177 Al and
comprises a pick box adapted to be secured, by welding, to a powered drum or
disc and having a bore to receive a replaceable sleeve having a collar and
also a
circular section bore to receive a circular section shank of a replaceable
mineral
cutter pick. The bore of the pick box incorporates at least one flat, and the
sleeve
is provided with at least one external flat to engage the flat of the pick
box,
whereby the sleeve is non-rotatable with respect to the box.
[05] US 7,229,136 B2 discloses a compressible sleeve for fitting
around the shank of a rotatable tool. The compressible sleeve has a cut out
portion at the forward end thereof and is compressed to a diameter less than
the
inner diameter of the bore of a tool holder by an annular wear ring having a
generally cylindrical central opening with a diameter larger than the diameter
of
the bore of the tool holder. When the shank of the tool is driven into the
bore of
the tool holder, the wear ring is forced forwardly along the sleeve until the
projection of the wear ring falls between the cut out portions of the sleeve
thereby
allowing the sleeve to expand to the diameter of the bore of the tool holder.
[06] Further, WO 2014/194978 A2 discloses a cutting head for hard
rock mining applications. The cutting head comprises a base member having a
rotational axis and a center bore extending along the rotational axis, a drive
bushing disposed within the center bore and configured to transmit torque from
a
driving device to the base member, a plurality of tool supports concentrically
disposed about the rotational axis at the base member in a releasable manner,
and
a plurality of cutting bit carriers attached to each of the plurality of tool
supports.
When at least one of the plurality of cutting bits is worn, the tool support
including the worn cutting bits is replaced by a new tool support including
new
cutting bits.
[07] Further, WO 2014/194979 A2 discloses a replaceable tool support
configured to be mounted to a cutting head used in hard rock mining
applications.
The disclosed tool support comprises an annular body, a plurality of cutting
bit
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-3-
carriers disposed spaced apart from each other on a first end face side of the
annular body, and a plurality of cutting bits. Each of the plurality of
cutting bits is
rotatably supported by one of the plurality of cutting bit carriers. When at
least
one of the plurality of cutting bits is worn, the tool support including the
worn
cutting bits may be replaced by another tool support including new cutting
bits.
[08] The present disclosure is directed, at least in part, to improving or
overcoming one or more aspects of prior systems.
Summary of the Disclosure
[09] According to an aspect of the present disclosure, a cutting bit
carrier for hard rock mining applications may comprise a first carrier member
including a first supporting portion configured to contact a cutting bit shank
of a
cutting bit for supporting the cutting bit, and a second carrier member
including a
second supporting portion configured to contact the cutting bit shank of the
cutting bit for supporting the cutting bit. The second carrier member may be
detachably mountable to the first carrier member.
[10] According to another aspect of the present disclosure, a tool
support configured to be mounted to a cutting head used in hard rock mining
applications may comprise an annular body, and a plurality of cutting bit
carriers
according to the present disclosure. At least one of the first carrier member
and
the second carrier member may be integrally formed with the annular body. The
tool support according to the present disclosure may further comprise a
plurality
of cutting bits rotatably supported by an associated one of the plurality of
cutting
bit carriers.
[11] According to another aspect of the present disclosure, a cutting
head used in hard rock mining applications may comprise a base member having
a rotational axis and including a plurality of tool support receiving portions
extending around the rotational axis, and a plurality of tool supports
according to
the present disclosure. Each of the plurality of tool supports may be
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-4-
concentrically disposed about the rotational axis at an associated tool
support
receiving portion in a releasable manner. The first carrier member may be
integrally formed with one of the plurality of tool supports, and the second
carrier
member may be integrally formed with an adjacent tool support.
[12] According to another aspect of the present disclosure, a method
for mounting a cutting bit to a cutting bit carrier provided at a cutting head
used
in hard rock mining applications is disclosed. The cutting bit may include a
cutting bit axis extending from a cutting bit head to a cutting bit end flange
via a
cutting bit shank. The method according to the present disclosure may comprise
the step of disposing the cutting bit shank at a first supporting portion
provided at
a first carrier member along a direction extending substantially perpendicular
with respect to the cutting bit axis. The first supporting portion may be
configured to at least partially contact the cutting bit shank for at least
partially
supporting the same. The method according to the present disclosure may
further
comprise the step of detachably mounting a second carrier member to the first
carrier member. The second carrier member may include a second supporting
portion configured to at least partially contact the cutting bit shank for at
least
partially supporting the same.
[13] According to another aspect of the present disclosure, a cutting bit
configured to be replaceable mounted to a cutting bit carrier provided at a
cutting
head used in hard rock mining applications is disclosed. The cutting bit
according
to the present disclosure may comprise a cone-like cutting bit head having a
tip
portion and a head base portion opposite to the tip portion. The cutting bit
head
may be configured to extract hard rock mining material. The cutting bit may
further comprise a substantially cylindrical cutting bit shank having a first
end
portion connected to the head base portion and a second end portion. The
cutting
bit shank may have a first diameter. The cutting bit may further comprise a
substantially cylindrical cutting bit end flange connected to the second end
portion of the cutting bit shank and having a second diameter substantially
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-5-
greater than the first diameter. The second diameter may be in a range from
about
120 % to about 200 % of the first diameter. Additionally or alternatively, the
head base portion may have a third diameter greater than the first diameter.
The
third diameter may be preferably in a range from about 120 % to about 200 % of
the first diameter.
[14] Other features and aspects of this disclosure will be apparent from
the following description and the accompanying drawings.
Brief Description of the Drawings
[15] The accompanying drawings, which are incorporated herein and
constitute a part of the specification, illustrate exemplary embodiments of
the
disclosure and, together with the description, serve to explain the principles
of the
disclosure. In the drawings:
Fig. 1 illustrates a perspective view of a modular cutting head used
in hard rock mining applications;
Fig. 2 illustrates an explosion view of an exemplary disclosed
cutting bit carrier with a first cutting bit carrier and a second cutting bit
carrier
detached from one another;
Fig. 3 illustrates a sectional view through the first carrier member
taken along line III ¨ III of Fig. 2;
Fig. 4 illustrates a side view of the second carrier member of Fig.
2;
Fig. 5 illustrates an exemplary disclosed cutting bit mountable to
the cutting bit carrier of Fig. 2;
Fig. 6 illustrates the cutting bit carrier of Fig 2 in an assembled
state with the cutting bit of Fig. 5 mounted to the cutting bit carrier;
Fig. 7 illustrates a sectional view of the cutting bit carrier taken
along line VII ¨ VII of Fig. 6;
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-6-
Fig. 8 illustrates a side view through a further exemplary disclosed
cutting bit carrier according to the present disclosure;
Fig. 9 illustrates a sectional view through the cutting bit carrier of
Fig. 8 taken along line IX ¨IX of Fig. 8;
Fig. 10 illustrates a partial cut view of a modular cutting head
provided with a plurality of further exemplary disclosed cutting bit carriers;
Fig. 11 illustrates a partial cut view of a modular cutting head
provided with a plurality of further exemplary disclosed cutting bit carriers;
Fig. 12 illustrates a partial cut view of a further modular cutting
head provided with a plurality of exemplary disclosed tool supports;
Fig. 13 illustrates a partial cut view of a further modular cutting
head provided with a plurality of further exemplary disclosed tool supports;
and
Fig. 14 illustrates a sectional view of an exemplary disclosed
cutting bit.
Detailed Description
[16] The following is a detailed description of exemplary embodiments
of the present disclosure. The exemplary embodiments described therein and
illustrated in the drawings are intended to teach the principles of the
present
disclosure, enabling those of ordinary skill in the art to implement and use
the
present disclosure in many different environments and for many different
applications. Therefore, the exemplary embodiments are not intended to be, and
should not be considered as, a limiting description of the scope of patent
protection. Rather, the scope of patent protection shall be defined by the
appended claims.
[17] The present disclosure may be based at least in part on the
realization that providing a two-piece cutting bit carrier may support in
facilitating replacement of worn cutting bits. Particularly, a worn cutting
bit may
CA 02992798 2018-01-17
WO 2017/012690
PCT/EP2016/001109
-7-
be replaced by a new cutting bit by disassembling the associated two-piece
cutting bit carriers without the need of a specific tool.
[18] The present disclosure may be further based in part on the
realization that, during operation of a cutting head used in hard rock mining
applications, the carrier members of the exemplary disclosed cutting bit
carriers
may maintain its attachment to one another due to at least partially self-
retention.
Specifically, operational forces may be used to at least partially clamp the
carrier
members to one another for ensuring proper assembly of the cutting bit carrier
and proper support of the associated cutting bit.
[19] In the following, detailed features of exemplary disclosed cutting
bit carriers, tool supports, and cutting bits are described with respect to
the
appended drawings. Referring to Fig.1, a perspective view of a cutting head 10
having a rotational axis 12 is illustrated. The cutting head 10 includes a
base
member 20, a plurality of tool supports 40, a plurality of cutting bit
carriers 100
attached to the plurality of tool supports 40, and a plurality of cutting bits
200.
Each of the plurality of cutting bits 200 may be rotatably supported by an
associated one of the plurality of cutting bit carriers 100 attached to an
associated
tool support 40. The tool supports 40 are mounted to tool support receiving
portions provided at the base member 20, respectively.
[20] In Fig. 1 the cutting head 10 is shown with a plurality of tool
supports 40, namely a first tool support 41, a second tool support 42, a third
tool
support 43, and a fourth tool support 44. Each of the tool supports 41, 42,
43, 44
has an annular shape and is concentrically disposed at the base member 20 with
respect to the rotational axis 12. In particular, each of the plurality of
annular tool
supports 40 is provided with a different outer diameter and includes an outer
chamfer 46 where the plurality of cutting bit carriers 100 are attached.
[21] The base member 20 may further include a center bore 30
extending through the base member 20 along the rotational axis 12 (see also
Fig.
2). The center bore 30 is configured to receive a drive bushing (not
explicitly
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-8-
shown in the drawings) receiving torque from a driving unit (not explicitly
shown
in the drawings) and transmitting the torque to the base member 20 and, thus,
to
the plurality of tool supports 40 and the plurality of cutting bits 200
configured to
engage the rock.
[22] For instance, the cutting head 10 may be substantially configured
as set out in WO 2014/194978 A2 and WO 2014/194979 A2, which are herein
incorporated by reference with respect to the configurations of the base
members,
the associated annular tool supports, and its specific assembly to the base
members.
[23] Each of the plurality of cutting bit carriers 100 is, as illustrated
in
Fig. 1, attached to the plurality of tool supports 40 by means of, for
example,
welding, soldering, glueing, or any other attaching means known in the art.
Particularly, as indicated in Fig. 1, each of the plurality of cutting bit
carriers 100
is a two-piece cutting bit carrier 100 including a first carrier member 110
and a
second carrier member 120 detachably mounted to one another, wherein the first
carrier member 110 is attached to an associated tool support 40 by means of,
for
instance, welding, soldering, glueing, or any other attaching means known in
the
art. In some further embodiments, the first carrier member 110 may be
integrally
formed with the associated tool support 40, such as, for instance, by molding.
[24] Referring to Figs. 2 to 4, 6, and 7, an exemplary disclosed carrier
member 100 including the first carrier member 110 and the second carrier
member 120 is illustrated. The first carrier member 110 includes a mounting
portion 112 for mounting the first carrier niember 110 to the associated tool
support 40, and a first supporting portion 114 configured to contact a cutting
bit
shank 204 of a cutting bit 200 (see Fig. 5) for supporting the cutting bit
200,
which will be described in greater detail below.
[25] The first supporting portion 114 includes a shape at least partially
corresponding to and matching with an outer shape of the cutting bit shank 204
and extends along a first carrier axis 101. The first supporting portion 114
is
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-9-
provided as a recess for accommodating the cutting bit shank 204. The first
carrier member 110 further includes a reception portion 116 formed as a
further
recess for at least partially receiving the second carrier member 120 and for
engaging the second carrier member 120. Particularly, the first supporting
portion
114 is provided in said recess forming the reception portion 116.
[26] The reception portion 116 according to the embodiment shown in
Figs. 2 to 4, 6, and 7 includes a plurality of first protrusions 118 at least
partially
protruding into the corresponding recess. For example, the first protrusions
118
substantially protrude in a radially inward direction with respect to the
first
carrier axis 101. Each of the first protrusions 118 includes a first inclined
lateral
surface 119, for example, a first inclined lower lateral surface (see
especially Fig.
3).
[27] The second carrier member 120 includes a second supporting
portion 124 including a shape at least partially corresponding to and matching
with the outer shape of the cutting bit shank 204. The second supporting
portion
124 is provided as a recess for accommodating the cutting bit shank 204. The
second supporting portion 124 substantially extends along a second carrier
axis
103.
[28] In the exemplary disclosed embodiment of Figs. 2 to 4, 6, and 7
the first supporting portion 114 and the second supporting portion 124 each
have
a semicircular cross-section. Thus, after assembling, the first supporting
portion
114 and the second supporting portion 124 together form a substantially
circular
cutting bit supporting portion corresponding to the circular cross-section of
the
associated cutting bit shank 204 for rotatably supporting the cutting bit 200.
[29] In an assembled state of the first carrier member 110 and the
second carrier member 120, the first carrier axis 101 and the second carrier
axis
103 are configured to coincide, i.e. to be coaxial to one another. Thus, the
first
supporting portion 114 and the second supporting portion 124 together form a
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-10-
cutting bit supporting portion for safely supporting an associated cutting bit
200,
particularly, the cutting bit shank 204 of the associated cutting bit 200.
[30] The first supporting portion 114 is configured to contact at least a
portion of a circumference of the cutting bit shank 204, and the second
supporting portion 124 is configured to contact at least partly a remaining
portion
of the circumference of the cutting bit shank 204. That is at least one
interface
between the first carrier member 110 and the second carrier member 120 is
parallel to the first carrier axis 101 and the second carrier axis 103 as well
as
parallel to the cutting bit axis 201. That is a partitioning plane between the
first
carrier member 110 and the second carrier member 120 is parallel to the first
carrier axis 101 and the second carrier axis 103 as well as parallel to the
cutting
bit axis 201.
[31] In the embodiments shown in the drawings, the first supporting
portion 114 and the second supporting portion 124 are configured to contact
the
entire cutting bit shank 204 in circumferential direction. However, in further
embodiments, the first supporting portion 114 and the second supporting
portion
124 are configured to contact only partially the cutting bit shank 204 in
circumferential direction.
[32] In Figs. 2 to 4, the first supporting portion 114 and the second
supporting portion 124 each form shell elements for supporting the cutting bit
shank 204 of an associated cutting bit 200.
[33] As illustrated, the second carrier member 120 includes a mounting
portion 126 configured to be received by and engage the reception portion 116.
In
particular, the mounting portion 126 is formed as a projection to be received
by
and at least partially inserted into the reception portion 116. The mounting
portion 126 includes a plurality of second protrusions 128 configured to
protrude
in a radially outward direction with respect to the second carrier axis 103.
Each of
the second protrusions 128 includes a second inclined lateral surface 129, for
example, a second inclined upper lateral surface 129 (see Fig. 4). The second
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-11-
inclined lateral surfaces 129 are configured to be substantially parallel to
the first
inclined lateral surfaces 119.
[34] When mounting the first carrier member 110 and the second
carrier member 120 to one another, the second carrier member 120 is moved
along the dashed arrows 102 (see Figs. 3 and 4). During said movement along
the
dashed arrows 102, each of the second protrusions 128 passes an associated
first
protrusion 118 until the first carrier axis 101 coincides with the second
carrier
axis 103, i.e. the reception portion 116 has at least partially received the
mounting portion 126. Then, the second carrier member 120 is moved along the
first carrier axis 101 and the second carrier axis 103.
[35] During movement of the second carrier member 120 along the
first carrier axis 101 and the second carrier axis 103, the first protrusions
118 and
the second protrusions 128 are shifted one below the other, such that the
second
carrier member 120 is locked in a direction perpendicular to the first carrier
axis
101 and the second carrier axis 103. Further, during movement of the second
carrier member 120 along the first carrier axis 101 and the second carrier
axis
103, the first inclined lateral surface 119 and the second inclined lateral
surface
129 get in contact with one another, thereby restricting further axial
movement of
the first carrier member 110 relative to the second carrier member 120. In
such
state, the second carrier member 120 is mounted to the first carrier member
110.
[36] As shown, the first protrusions 118 substantially protrude in a
radially inward direction with respect to the first carrier axis 101, and the
second
protrusions 128 substantially protrude in a radially outward direction with
respect
to the second carrier axis 103. Thus, the first protrusions 118 and the second
protrusions 128 at least partially engaging each other form at least partially
a kind
of a dovetail guide.
[37] It is explicitly stated that the directions of projection of the first
protrusions 118 and the second protrusions 128 may be vice versa,
respectively,
i.e. the first protrusions 118 may protrude in a radially outward direction
with
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-12-
respect to the first carrier axis 101, and the second protrusions 128 may
protrude
in a radially inward direction with respect to the second carrier axis 103. In
such
embodiments, the mounting portion 126 may be configured as the reception
portion 116, and the reception portion 116 may be configured as the mounting
portion 126.
[38] Further, in the embodiment shown in Figs. 2 to 4, 6, and 7,
the
first carrier member 110 includes in total three first protrusions 118 and the
second carrier member 120 includes in total three second protrusions 128.
However, the number of protrusions is not limited to three, such that there
may
be more or less than three first and second protrusions 118, 128 provided that
engage one another, respectively.
[39] Referring to Fig. 5, an exemplary disclosed cutting bit 200
replaceable mountable to the cutting bit carrier 100 of, for example, Figs. 2
to 4,
6, and 7 is illustrated. The cutting bit 200 extends along the cutting bit
axis 201
and includes a cone-like cutting bit head 202, the cutting bit shank 204
configured to be supported by the cutting bit carrier 100, and a cutting bit
flange
206.
[40] The cutting bit head 202 includes a tip portion 203 made of,
for
example, hardened material, and a head base portion 205. The cutting bit shank
204 is substantially cylindrical and has a first end portion 207 connected to
the
head base portion 205 and a second end portion 209 opposite the first end
portion
207. The cutting bit flange 206 is connected to the second end portion 209 of
the
cutting bit shank 204.
[41] The cylindrical cutting bit shank 204 has a first diameter
D1, the
cutting bit flange 206 has a second diameter D2, and the head base portion 205
of
the cone-like cutting bit head 202 has a third diameter D3. As shown, the
second
diameter D2 is substantially greater than the first diameter Dl. In
particular, the
second diameter D2 may be in a range from about 120 % to about 200 % of the
first diameter Dl.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-13-
[42] As further illustrated, the third diameter D3 is substantially greater
than the first diameter Dl. In particular, the third diameter D3 may be in a
range
from about 120 % to about 250 % of the first diameter D1, and/or in a range
from
about 80 % to about 150 % of the second diameter D2. For example, the first
diameter D1 may be in a range from about 15 mm to about 30 mm, the second
diameter D2 may be in a range from about 30 mm to about 50 mm, and the third
diameter D3 may be in a range from about 30 mm to about 40 mm.
[43] Referring to Fig. 6, the cutting bit carrier 100 supporting the
cutting bit 200 of Fig. 5 is depicted. As can be seen in Fig. 6, the cutting
bit head
202 protrudes out of cutting bit carrier 100 at a first side, wherein at least
a
portion of the cutting bit shank 204 together with the cutting bit flange 206
protrudes out of the cutting bit carrier 100 and a second side opposite to the
first
side. Hence, a majority portion of the cutting bit shank 204 is supported by
the
cutting bit carrier 100, particularly by the first carrier member 110 and the
second
carrier member 120.
[44] Fig. 7 illustrates a cut view through the cutting bit carrier 100 and
the cutting bit 200 taken along line VII¨ VII of Fig. 6. As shown in Fig. 7,
in an
assembled state of the cutting bit carrier 100, each of the first inclined
lateral
surfaces 119 of the first protrusions 118 are in contact with an associated
second
inclined lateral surface 129 of the second protrusions 128. In particular, the
first
inclined lateral surfaces 119 and the second inclined lateral surfaces 129
each
have an inclination, such that movement of the second carrier member 120 along
the second carrier axis 103 in a direction away from the cutting bit head 202
is
restricted, but in a direction towards the cutting bit head 202, the second
carrier
member 120 is freely movably relative to the first carrier member 110.
[45] During operation of the cutting bit 200, axial forces indicated by
an arrow 210 in Fig. 7 may occur. The axial forces 210 affect a self-locking
feature of the second carrier member 120 with respect to the first carrier
member
110, as the head base portion 205 of the cutting bit head 202 may at least
partially
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-14-
push against the second carrier member 120 thereby pushing the second inclined
lateral surfaces 129 against the first inclined lateral surfaces 119,
respectively.
[46] The length of the cutting bit shank 204 is configured to allow
proper assembly of the cutting bit carrier 100. Thus, an excessive length 220
(see
Fig. 7), which protrudes out of the cutting bit carrier 100 at the second
side, is at
least partially greater than an engagement width of the first protrusions 118
and
the second protrusions 128 along direction of the first carrier axis 101 and
the
second carrier axis 103, respectively. The engagement width is defined by the
width along the first carrier axis where a first inclined lateral surface 119
is in
contact with an associated second inclined lateral surface 129. Thus, movement
of the second carrier member 120 along the dashed arrows 102 for mounting to
the first carrier member 110 is enabled in both axial directions.
[47] Referring now to Figs. 8 and 9, a further exemplary disclosed two-
piece cutting bit carrier 100 supporting a cutting bit 200 is illustrated. As
shown,
the cutting bit carrier 100 of Figs. 8 and 9 includes the first carrier member
110
and the second carrier member 120 detachably mounted to the first carrier
member 110, but without the first protrusions 118 and the second protrusions
128
as described with respect to Figs. 2 to 4 and 6 to 7. Therefore, same elements
are
denoted with same reference signs.
[48] Instead of the first and second protrusions 118, 128, the mounting
portion 126 of the second carrier member 120 is a projection received by the
reception portion 116 formed as a corresponding recess. The first supporting
portion 114 is provided in said recess forming the reception portion 116, and
the
second supporting portion 124 is provided in said projection forming the
mounting portion 126.
[49] In order to prevent the first carrier member 110 and the second
carrier member 120 from detaching from one another, a locking element 130 is
provided. Specifically, the locking element 130 as shown in Fig. 9 is a C-
shaped
element having a first elongated portion 132 extending into and through a
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-15-
through hole 117 formed in the first carrier member 110. The locking element
130 further includes a second elongated portion 134 extending into and through
a
through hole 127 formed in the second carrier member 120. The first elongated
portion 132 and the second elongated portion 134 are connected to one another
via an intermediate portion 136.
[50] The first through hole 117 and the second through hole 127
substantially extend perpendicular with respect to the first carrier axis 101,
the
second carrier axis 102, and the cutting bit axis 201, respectively, wherein
all
three axes substantially coincident in an assembled state of the carrier
member
100 with a mounted cutting bit 200. In order to prevent the locking element
130
from detaching from the first carrier member 110 and the second carrier member
120, the first elongated portion 132 projecting out of the first through hole
117
and the second elongated portion 134 projecting out of the second through hole
may each be locked in said protruding state by, for example, plastically
deformation, such as bending by 90 .
[51] In some further embodiments, the locking element 130 may be
locked relative to the first and second carrier members 110, 120 by, for
example,
frictional locking or by providing a bushing at the projecting ends of the
first and
second elongated portions 132, 134, respectively.
[52] As illustrated in Fig. 8, the cutting bit carrier 100 includes two
locking elements 130 spaced apart one another. However, it should be noted
that
cutting bit carriers 100 according to further embodiments may include only one
or more than two locking elements 130.
[53] During assembly of the cutting bit carrier 100 of Figs. 8 and 9, and
after positioning the cutting bit 200 at the first supporting portion 114 of
the first
carrier member 110, the second carrier member 120 is moved perpendicularly
with respect to the cutting bit axis 201, such that the mounting portion 126
is at
least partially received by the reception portion 116 and such that the first
supporting portion 114 and the second supporting portion 124 together form the
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-16-
cutting bit supporting portion for the cutting bit shank 204. Thus, in
comparison
with the cutting bit carrier 100 of Figs. 2 to 4, no axial movement of the
second
carrier member 120 relative to the first carrier member 110 along the cutting
bit
axis 201 is necessary. Instead, for securing the first carrier member 110 and
the
second carrier member 120 to one another, the locking element(s) 130 is (are)
inserted into the first and second through holes 117, 127, respectively.
[54] In the embodiment shown in Figs. 8 and 9, the length of the
cutting bit shank 204 may correspond to the lengths of the first supporting
portion
114 and the second supporting portion 124, such that no excessive length 220
(see Fig. 7) of the cutting bit shank 204 is necessary.
[55] Referring now to Fig. 10, a partial cut view of a cutting head 10
provided with a plurality of tool supports 40 is shown. As can be seen in Fig.
10,
the first carrier member 110 is integrally formed with an associated tool
support
40. In such embodiment, the second carrier member 120 is similarly designed as
the second carrier member 120 of Figs. 8 and 9. In Fig. 10, the second carrier
member 120 includes an attachment member 125 configured to be detachably
mounted to the associated tool support 40 by, for instance, bolting, glueing,
pinning etc.. In some further embodiments, the attachment member 125 may be
detachably mounted to the associated tool support 40 by, for example,
providing
a bayonet.
[56] In the embodiment shown in Fig. 10, it is possible to replace worn
cutting bits 200 independently from one another. In particular, worn cutting
bits
200 of one of the tool supports 40 can be replaced by a new cutting bit 200
independently from one another by detaching the second carrier member 120 and
replacing the worn cutting bit 200 with a new one. Hence, detaching of the
overlying tool supports 40 is not necessary.
[57] With respect to Fig. 11, a further embodiment of a cutting bit
carrier 100 and annular tool supports 40 is illustrated. As shown, the first
carrier
member 110 is integrally formed with an associated tool support 42, wherein
the
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-17-
second carrier member 120 is integrally formed with the tool support 41 above
the tool support 42. That is, for instance, the attachment member 125 of the
second carrier member 120 of Fig. 10 is integrally formed with the tool
support
41 in Fig. 11.
[58] During assembly, at first the tool support 42 is placed about the
base member 20 (not shown in Fig. 11). Then, cutting bits 200 are positioned
at
associated first supporting portions 124 of the first carrier members 110
integrally
formed with the tool support 42. Subsequently, the tool support 41 is placed
about the base member 20 above the tool support 42 at the base member 20.
During said placement of the tool support 41, the second supporting portions
124
of the second carrier members 120 integrally formed with the tool support 41
get
in contact with the associated cutting bits 200, respectively, for supporting
the
cutting bit shanks 204. In said state, the cutting bits 200 are safely
supported by
two adjacent tool supports 41, 42.
[59] As shown in Figs. 1 to 11, each of the plurality of cutting bits 200
has a substantially horizontal orientation with respect to the rotational axis
12, i.e.
the cutting bit axes 201 of the cutting bits 200 lie in a plane perpendicular
to the
rotational axis 12. However, it should be noted that the cutting bit axes 201
may
have an inclination with respect a plane perpendicular to the rotational axis
12 (as
shown, for example, in Figs. 12 and 13).
[60] With respect to Figs. 12 and 13, a further alternative for
supporting cutting bits 200 at a cutting head 10 is illustrated in greater
detail. In
particular, for the sake of simplicity, the cutting head 10 of Figs. 12 and 13
is
illustrated with two annular tool supports 41, 42, only. However, it should be
noted that the cutting head 10 may include more than two tool supports 41, 42
each supporting a plurality of cutting bits 200.
[61] Referring to Fig. 12, a partial cut view through the cutting head 10
is shown. The cutting head 10 includes two tool supports 41, 42 each having an
annular body 90 provided with different outer diameters and mounted one above
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-18-
the other, thereby forming the substantially cone-like cutting head 10. Each
of the
annular tool supports 41, 42 extends about the rotational axis 12.
[62] Each annular body 90 has a first axial end face 95 and a second
axial end face 97 opposite the first axial end face 95. Each annular body 90
further includes a plurality of supporting holes 92 each extending along a
supporting hole axis through the annular body 90 from the first axial end face
95
to the second axial end face 97. The supporting holes 92 are configured to
support cutting bits 200, respectively, in particular the cutting bit shanks
204 of
the cutting bits 200. The supporting holes 92 are disposed spaced apart from
one
another about the rotational axis 12.
[63] The cutting bits 200 of Fig. 12 differ from the cutting bits 200 of
Fig. 5 in that the third diameter D3 of the head base portion 205 of the
cutting
head 202 is equal to the first diameter D1 of the cutting bit shank 204. That
is the
cutting bit shank 204 smoothly transitions into the cutting bit head 202.
[64] The annular body 90 of the tool support 42, namely the tool
support below the tool support 41, includes a plurality of supporting
projections
94 configured to substantially protrude from the first axial end face 95
towards
the overlying tool support 41. The supporting projections 94 are configured to
support associated cutting bit flanges 206 of the cutting bits 200 supported
by the
supporting holes 92. Each of the supporting protrusions 94 has a supporting
surface 96 configured to contact and support an end face of an associated
cutting
bit flange 206. Each of the plurality of supporting surfaces 96 are planar for
contacting and abutting an associated planar end face of an associated cutting
bit
flange 206. Preferably, the supporting surfaces 96 are perpendicular with
respect
to the cutting bit axis 201 along which the cutting bits 200 substantially
extend.
[65] As further illustrated in Fig. 12, the tool support 41 includes a
supporting recess 98 formed in the second axial end face 97 and configured to
at
least partially receive and support an associated cutting bit flange 206.
Thus, each
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-19-
cutting bit 200 is partially supported by the tool support 41 and partially
supported by the tool support 42 disposed below the tool support 41.
[66] The supporting hole 92 includes a shape substantially
corresponding to the outer shape of the associated cutting bit shank 204. As
shown in Fig. 12, the cutting bit flange 206 includes the second diameter D2
substantially greater than the first diameter D1 of the cutting bit shank 204.
[67] The supporting protrusions 94 are disposed spaced apart one
another about the rotational axis 12. Particularly, the supporting protrusions
are
disposed on a first circle about the rotational axis 12 with a first radius.
The
supporting holes 92 are disposed on a second circle about the rotational axis
with
a second radius. As indicated in Fig. 12, the first radius is smaller than the
second
radius (see especially tool support 42 in Fig. 12).
[68] During assembly, at first the tool support 42 is placed about the
base member 20 (not shown in Fig. 11). Then, cutting bits 200 are positioned
at
associated supporting protrusions 94, such that the end faces of the cutting
bit
flanges 206 are in contact with the supporting surfaces 96, respectively.
Subsequently, the tool support 41 is placed about the base member 20 above the
tool support 42, such that the cutting bit heads 202 pass through the
supporting
holes 92, respectively, and that the cutting bit shanks 204 are supported by
and
positioned within the supporting holes 92, respectively. After placement of
the
tool support 41 above the tool support 42, the cutting bit flanges 206 are at
least
partially positioned within the supporting recesses 98, respectively. In said
state,
the cutting bits 200 are safely supported by two adjacent tool supports 41,
42.
[69] Due to the second diameter D3 of the cutting bit flange 206 that is
greater than the first diameter D1 of the cutting bit shank 204 and, hence,
greater
than the diameter of the supporting hole 94, the cutting bits 200 are
prevented
from falling out of its supported position. As indicated, the supporting holes
92
and the supporting recesses 98 are configured to have dimensions to allow a
rotatably support of the cutting bits 200.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-20-
[70] In the embodiment of Fig. 12, each of the annular tool supports 41,
42 incorporate the functions of the cutting bit carriers. Thus, no separate
cutting
bit carriers are necessary.
[71] Referring now to Fig. 13, a cutting head 10 provided with a further
embodiment of exemplary disclosed tool supports 41, 42 is shown. The tool
support 41 of Fig. 13 differs from the tool support 41 of Fig. 12 in that
additional
supporting bushings 91 are positioned and detachably mounted to mounting holes
93 provided in the tool support 41, respectively. The supporting bushings 91
include the supporting holes 92 for supporting the cutting bit shanks 204,
respectively.
[72] A diameter of the mounting holes 93 is adapted to allow the entire
cutting bit 200 to be mountable to the respective tool support 41 even when
the
tool supports 41, 42 are assembled to one another. The supporting bushings 91
are detachably mounted to the mounting holes 93 via, for instance, bolting,
screwing, glueing, pressing, pinning etc..
[73] In the embodiment shown in Fig. 13, it is possible to replace worn
cutting bits 200 independently from one another, even in an assembled state of
the cutting head 10. In particular, worn cutting bits 200 of one of the tool
supports 41, 42 can be replaced by a new cutting bit 200 independently from
one
another by detaching the associated supporting bushing 91 and replacing the
worn cutting bit 200 with a new one.
[74] In Figs. 12 and 13, each of the plurality of cutting bits 200 has a
specific orientation with respect to the rotational axis 12, i.e. the cutting
bit axes
201 of the cutting bits 200 obliquely extend with respect to a plane
perpendicular
to the rotational axis 12. The degree of inclination of the cutting bit axes
201 may
be selected as desired. Preferably, the cutting bit axes 201 may each be
provided
in a skew manner with respect to the rotational axis 12.
[75] With respect to Fig. 14, an alternative embodiment of a cutting bit
300 mounted to, for example, an annular tool support 40 (see Fig. 1) is
illustrated.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-21-
However, in some embodiments, the cutting bit 300 may be mountable to any
known cutting head that includes a configuration different to the one as shown
in
Fig. 1. For example, the cutting bit 300 is replaceable mountable to a non-
modular cutting head.
[76] As shown in Fig. 14, the cutting bit 300 comprises a main body
302 extending along a cutting bit axis 301. The main body 302 includes a base
portion 304, a tip end portion 306, and a cone-like intermediate portion 305
connecting the base portion 104 and the tip end portion 306 to one another. A
substantially cylindrical supporting recess 308 is formed in an end face of
the
base portion 304 and extends along the cutting bit axis 301 at least partially
into
the main body 302.
[77] A substantially cylindrical cutting bit tip mounting recess 309 is
formed in an end face of the tip end portion 306 and extends along the cutting
bit
axis 301 at least partially into the main body 302. Both the supporting recess
308
and the mounting recess 309 may be, for example, drilled or milled bores.
[78] The cutting bit tip mounting recess 309 is configured to
accommodate a hardened cutting bit tip element 303 via, for instance, pressure
fit. In some embodiments, the cutting bit tip element 303 may be mounted to
the
mounting recess 309 via screwing, gluing, welding, soldering, or any other
fixing
means known in the art for mounting a hardened cutting bit tip element 303 to
the
mounting recess 309.
[79] The cutting bit 300 is mountable to, for example, one of the tool
supports 40 as shown in Fig. 1. Particularly, an associated tool support 40
includes a substantially cylindrical supporting protrusion 48 corresponding to
and
matching with the supporting recess 308. As illustrated in the exemplary
embodiment of Fig. 14, the cylindrical supporting protrusion 48 may be
integrally
formed with the associated tool support 40. However, in further embodiments,
the supporting protrusion 48 may be mounted to the associated tool support 40
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-22-
via, for example, glueing, bolting, screwing, welding, soldering, pinning, or
any
other known attaching means.
[80] The main body 302 can be put onto or at least partially slipped
over the associated supporting protrusion 48 and locked in an assembled state
via,
for example, a snap ring 310 provided between an inner wall of the supporting
recess 309 and a lateral outer surface of the supporting protrusion 48. The
snap
ring 310 is configured to allow rotational movement of the main body 302
relative to the supporting protrusion 48 and to disallow axial movement of the
main body 302 relative to the supporting protrusion 48.
[81] In the assembled state shown in Fig. 14, the snap ring 310 is at
least partially positioned in corresponding first and second grooves 312, 314
circumferentially extending about the cutting bit axis 301 and provided in the
supporting portion 308 and in the supporting protrusion 48, respectively. In
particular, the main body 302 includes a first groove 312 circumferentially
extending about the inner wall of the supporting recess 308, and the
supporting
protrusion 48 includes a second groove 314 circumferentially extending about
the
lateral outer surface thereof.
[82] In further embodiments, the supporting recess 309 may have a
substantially conical shape. In such cases, the supporting protrusion 48 may
also
have a substantially conical shape corresponding to and matching with the
conical supporting recess 308.
Industrial Applicability
[83] In the following, mounting of a cutting bit 200 to an associated
cutting bit carrier 100 is described with reference to Figs. 2 to 4, and Figs.
6 to
10.
[84] First, the cutting bit 200 is positioned at the first carrier member
110, such that the cutting bit shank 204 is in contact with the first
supporting
portion 114. Then, the second carrier member 120 is moved along the arrows
CA 02992798 2018-01-17
WO 2017/012690
PCT/EP2016/001109
-23-
102, namely at first in a direction perpendicular to the cutting bit axis 201
and
then, after the second protrusions 128 have passed the first protrusions 118,
the
second carrier member 120 is moved along the cutting bit axis 201 until the
second inclined lateral surfaces 129 get in contact with the first inclined
lateral
surfaces 119. In this state, the first carrier member 110 and the second
carrier
member 120 are mounted to one another, but the second carrier member 120 is
still at least partially movable relative to the first carrier member 110,
namely in
an axial direction towards the cutting bit head 202.
[85] During operation of the cutting head 10, the cutting bits 200
engage and extract hard rock material wherein axial forces 210 are applied on
the
cutting bits 200. Said axial forces 210 affect a self-retention of the first
carrier
member 110 and the second carrier member 120 to one another. Particularly,
said
axial forces 210 push the second inclined lateral surfaces 129 against the
first
inclined lateral surfaces 119 thereby strengthening the self-retention and,
thus,
the assembly of the first carrier member 110 and the second carrier member
120.
[86] When replacing worn cutting bits 200, the second carrier member
120 is detached from the first carrier member 110 in a reversed direction
along
the arrows 102 as described above (see Figs. 3 and 4).
[87] With respect to Fig. 11, for replacing worn cutting bits 200, at first
the overlying tool supports 40 need to be detached from the base member 20.
Then, the worn cutting bits 200 may be replaced by new cutting bits 200 and,
subsequently, the above lying tool supports 40 are mounted to the base member
20 again.
[88] In the following, mounting of a cutting bit 200 to an associated
tool support 41, 42 is described with reference to Fig. 12.
[89] At first, the tool support 41 is disassembled from the base member
20. Then, cutting bits 200 are positioned at each of the supporting
protrusions 94
provided at an subjacent tool support 42, such that the end faces of the
cutting bit
flanges 206 are in contact with the supporting surfaces 96, respectively.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-24-
Subsequently, the overlying tool support 41 is re-mounted to the base member
20, such that the cutting bit shanks 204 are supported by the supporting holes
92
and that the cutting bit heads 202 protrude out of the supporting holes 92,
respectively.
[90] In the following, mounting of a cutting bit 200 to an associated
tool support 40, 41, 42 is described with reference to Fig. 13.
[91] When any one of the cutting bits 200 is worn, only the associated
supporting bushing 91 is disassembled from the respective mounting hole 93,
i.e.
the overlying tool support 41 does not need to be disassembled. Then, the worn
cutting bit 200 is removed and replaced by a new cutting bit 200, such that
the
end face of the cutting bit flange 206 is in contact with the associated
supporting
surface 96. In a final step, the supporting bushing 91 is slipped over the
cutting
bit shank 204 and re-mounted to the mounting hole 93.
[92] In an alternative assembly method, the cutting bit 200 is mounted
to the supporting bushing 91 first and, subsequently, said assembly is mounted
to
the mounting hole 93.
[93] In the following, mounting of a cutting bit 300 to an associated
cutting head 10 is described with reference to Fig. 14.
[94] At first, the snap ring 310 is positioned in the second groove 314
circumferentially extending about the supporting protrusion 48 provided at,
for
example, one of the tool supports 40. Then, the supporting recess 308 of the
main
body 302 of the cutting bit 300 is put onto or slipped over the associated
supporting protrusion 48, and the snap ring 310 is elastically deformed, such
that
its diameter temporarily reduces. In such state, the snap ring 310 is mainly
position within the second groove 314 and has an outer diameter allowing the
cutting bit to be axially moved beyond the snap ring 310.
[95] Subsequently, the main body 302 of the cutting bit 300 is moved
along the cutting bit axis 301 until the snap ring 310 can radially deform to
its
initial state and at least partially engages the first groove 312 provided in
the
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-25-
supporting recess 308. Therefore, the radial thickness of the snap ring 310 is
equal to or at least partially smaller than the depth of the second groove
314. In
this assembling stage, the cutting bit 300 is mounted to the supporting
protrusion
48 in a rotatable manner, but the cutting bit 300 is prevented from axially
moving
relatively to the supporting protrusion 48.
[96] In order to ensure proper assembly of the cutting bit 300 and the
supporting protrusion 48, the first groove 312 may be provided with
inclinations
that urge the snap ring 310 into the second groove 314 while slipping the
cutting
bit 300 onto the supporting protrusion 48.
[97] In some embodiments, assembling of the cutting bit 300 and the
supporting protrusion 48 may be done by first mounting the snap ring 310 into
the first groove 312 and, then, mounting the cutting bit 300 with the engaged
snap ring 310 onto the supporting protrusion 48.
[98] The supporting protrusion 48 shown in Fig. 14 is formed, for
example, at an annular tool support 40. However, in further embodiments, the
supporting protrusion 48 may be formed at any cutting head 10 configured to
employ cutting bits 300 for extracting hard rock material. For example, with
respect to a non-modular cutting head 10 not including a plurality of annular
tool
supports 40, the supporting protrusions 48 may be formed directly at the base
member of the cutting head.
Further aspects
[99] In the following, further aspects of the present disclosure are
described. Those aspects include features already described herein in
connection
with the above description and Figs. 1 to 14.
[100] According to a second aspect of the present disclosure, a tool
support configured to be mounted to a cutting head used in hard rock mining
applications may comprise an annular body extending about a rotational axis
and
having a first axial end face and a second axial end face opposite the first
axial
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-26-
end face. The tool support according to the second aspect may further comprise
a
plurality of supporting holes disposed spaced apart one another about the
rotational axis and extending along a supporting hole axis from the first
axial end
face to the second axial end face. Each of the plurality of supporting holes
may
be configured to support a cutting bit shank of a cutting bit.
[101] The second aspect of the present disclosure may be based at least
in part on the realization that providing annular tool supports mountable to a
modular cutting head and provided with through holes for supporting cutting
bits
may render separate cutting bit carriers unnecessary. In particular, the
annular
tool supports according to the second aspect may incorporate the functions of
the
cutting bit carriers in the form of through holes and support sections
directly
formed at and integrally with the annular tool support.
[102] The second aspect of the present disclosure may be further based
at least in part on the realization that replacing of worn cutting bits and
cleaning
of the cutting bits may be facilitated. Further, manufacturing of the cutting
bits
may be facilitated and, hence, the manufacturing costs of the cutting bits may
be
reduced.
[103] In some embodiments, the tool support may further comprise a
plurality of supporting recesses provided at the second axial end face and
extending substantially along the supporting hole axis. Each of the plurality
of
supporting recesses may be configured to at least partially support and
accommodate an associated cutting bit end flange of the cutting bit.
[104] In some embodiments, the tool support may further comprise a
plurality of supporting protrusions protruding from the first axial end face.
The
plurality of supporting protrusions may be configured to at least partially
support
an end face of an associated cutting bit end flange of a cutting bit supported
by an
overlying annular tool support. Preferably, the supporting protrusions may
each
be configured to extend along the cutting bit axis.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-27-
[105] In some embodiments, each of the plurality of supporting
protrusions may include a supporting surface configured to contact the end
face
of the cutting bit end flange of the cutting bit supported by the overlying
annular
tool support.
[106] In preferred embodiments, the supporting surface is substantially
planar.
[107] In further preferred embodiments, the planar supporting surface
may be substantially perpendicular with respect to the cutting bit axis of the
cutting bit supported by the overlying annular tool support.
[108] In some embodiments, each of the plurality of supporting
protrusions may be disposed on a first circle about the rotational axis. The
first
circle may have a first radius.
[109] In some embodiments, the plurality of supporting holes may be
disposed on a second circle about the rotational axis. The second circle may
have
a second radius.
[110] In a preferred embodiment, the first radius may be smaller than the
second radius.
[111] According to a further second aspect of the present disclosure, a
method for mounting a cutting bit to a modular cutting head used in hard rock
mining applications is disclosed. The cutting bit may include a cutting bit
head, a
cutting bit shank connected to the cutting bit head, and a cutting bit end
flange
connected to the cutting bit shank. The method according to the further second
aspect may comprise positioning the cutting bit at a cutting bit supporting
protrusion provided at a first annular tool support, and placing a second
annular
tool support above the first annular tool support, such that, during placing
the
second annular tool support above the first annular tool support, the cutting
bit
head completely passes through a supporting hole formed in the second annular
tool support and that the supporting hole supports the cutting bit shank.
CA 02992798 2018-01-17
WO 2017/012690
PCT/EP2016/001109
-28-
[112] In some embodiments, the method may comprise mounting a
supporting bushing to the annular tool support, wherein the supporting bushing
provided with the supporting hole is configured to at least partially support
the
associated cutting bit.
Yet further aspects
[113] In the following, yet further aspects of the present disclosure are
described. Those aspects include features already described herein in
connection
with the above description and Figs. 1 to 14.
[114] According to a third aspect of the present disclosure, a cutting bit
replaceable mountable to a cutting head used in hard rock mining applications
may comprise a main body having a cutting bit axis and including a base
portion
and a tip end portion opposite to the base portion. The cutting bit may
further
comprise a supporting recess formed in an end face of the base portion and
extending at least partially along the cutting bit axis. The supporting recess
may
be configured to be slipped at least partially over a supporting protrusion
formed
at the cutting head.
[115] The present disclosure may be further based on the realization that
providing a cutting bit having a mounting recess and mountable to a cutting
head
by at least partially inserting a mounting protrusion formed at the cutting
head
into the mounting recess may facilitate replacement of worn cutting bits.
[116] The third aspect of the present disclosure may be further based at
least in part on the realization that manufacturing of the cylindrical
supporting
protrusions may be facilitated and cleaning of the cutting bit may be
simplified.
Further, the volume of the cutting bit may be reduced which may lead to less
manufacturing costs.
[117] In some embodiments, the supporting recess may be a
substantially cylindrical recess configured to be at least partially
accommodate
the corresponding cylindrical supporting protrusion provided at the cutting
head.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-29-
[118] Alternatively, the supporting recess may be a substantially conical
recess configured to at least partially accommodate the corresponding conical
supporting protrusion proved at the cutting head.
[119] In some embodiments, the cutting bit may further comprise a
supporting recess groove formed in an inner wall of the supporting recess and
circumferentially extending about the cutting bit axis. The supporting recess
groove may be configured to at least partially receive a snap ring for
mounting
the cutting bit to the cutting head.
[120] In some embodiments, the main body includes a cone-like
intermediate portion interconnected between the base portion and the tip end
portion.
[121] In some embodiments, the cutting bit may further comprise a
cutting tip mounting recess formed in an end face of the tip end portion and
extending at least partially along the cutting bit axis. The cutting tip
mounting
recess may be configured to at least partially accommodate a cutting bit tip
made
of hardened material.
[122] In preferred embodiments, the cutting tip mounting recess may be
configured to accommodate the cutting bit tip in a pressure fit manner.
[123] According to a further third aspect of the present disclosure, a
cutting head used in hard rock mining applications may comprise a base member,
and a plurality of supporting protrusions each configured to rotatably support
a
cutting bit by at least partially slipping the cutting bit over an associated
support
protrusion.
[124] In some embodiments, at least one of the plurality of supporting
protrusions may have a cylindrical shape with a substantially circular cross-
section.
[125] Alternatively or additionally, at least one of the plurality of
supporting protrusions may have a conical shape with substantially circular
cross-
sections with diameters gradually varying in an axial direction.
CA 02992798 2018-01-17
WO 2017/012690 PCT/EP2016/001109
-30-
[126] In some embodiments, each of the plurality of supporting
protrusions may comprise a supporting protrusion groove circumferentially
extending about a lateral surface thereof. The supporting protrusion groove
being
configured to at least partially receive a snap ring for mounting the cutting
bit to
the supporting protrusion.
[127] In some embodiments, the cutting head may be a modular cutting
head comprising a plurality of superimposed annular tool supports. Each of the
annular tool supports include the plurality of supporting protrusions for
rotatably
supporting a cutting bit according to the third aspect of the present
disclosure.
[128] According to yet another third aspect of the present disclosure, a
method for mounting a cutting bit to a cutting bit carrier provided at a
cutting
head used in hard rock mining applications is disclosed. The cutting bit may
include a main body having a cutting bit axis and including a base portion and
a
tip end portion opposite to the base portion. The cutting bit may further
comprise
a supporting recess formed in an end face of the base portion and extending at
least partially along the cutting bit axis. The method may comprise slipping
the
main body at least partially over an associated supporting protrusion provided
at
the cutting head and axially securing the main body to the cutting head.
[129] In some embodiments, the step of axially securing the main body
to the cutting head may include positioning a snap ring between the main body
and the supporting protrusion. The snap ring may be configured to allow
rotational movement of the main body relative to the supporting protrusion and
to
disallow axial movement of the main body relative to the supporting
protrusion.
[130] It should be noted that each recited aspect of the present disclosure
and embodiments thereof may be combined with other aspects and embodiments
thereof. As one skilled in the art will further appreciate, each individual
aspect
and embodiment recited herein may also be combined with any feature described
in connection with Figs. 1 to 14 where applicable.
CA 02992798 2018-01-17
WO 2017/012690
PCT/EP2016/001109
-31-
[131]
Although the preferred embodiments of this invention have been
described herein, improvements and modifications may be incorporated without
departing from the scope of the following claims.
