U.S. patent number 3,604,755 [Application Number 04/844,551] was granted by the patent office on 1971-09-14 for cutter bar, cutter chain and sprocket assembly.
This patent grant is currently assigned to The Cincinnati Mine Machinery Co.. Invention is credited to Claude B. Krekeler.
United States Patent |
3,604,755 |
Krekeler |
September 14, 1971 |
CUTTER BAR, CUTTER CHAIN AND SPROCKET ASSEMBLY
Abstract
A cutter bar, cutter chain and sprocket assembly wherein means
are provided to maintain the pintles joining the chain links in
spaced relationship to and beyond the chain guide surfaces on the
peripheral edges of the cutter bar. The ends of the pintles are
free to extend beyond the exterior surfaces of the links they join,
although they do not necessarily have to be so arranged. The
pintles are preferably freely rotatable and means may be provided
at their ends to hold the pintles in place with respect to the
links they join. The pintles are so located and the link so
configured that the line of force passing through the pintles also
passes through body portions of the links which support cutter bits
so that the distance between this line of force and the points of
contact between the cutter bits and the material being mined is
greatly reduced.
Inventors: |
Krekeler; Claude B.
(Cincinnati, OH) |
Assignee: |
The Cincinnati Mine Machinery
Co. (Cincinnati, OH)
|
Family
ID: |
25293037 |
Appl.
No.: |
04/844,551 |
Filed: |
July 24, 1969 |
Current U.S.
Class: |
299/84.1; 83/820;
83/788; 474/156 |
Current CPC
Class: |
E21C
25/28 (20130101); Y10T 83/7264 (20150401); Y10T
83/707 (20150401) |
Current International
Class: |
E21C
25/00 (20060101); E21C 25/28 (20060101); E21c
025/30 (); E21c 025/34 () |
Field of
Search: |
;299/82,83,84
;74/229,250 ;143/32 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Purser; Ernest R.
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defied as follows:
1. A cutter bar, cutter chain and sprocket assembly for a mining
machine and the like wherein said cutter bar comprises an elongated
member having longitudinal edge portions, a chain-driving sprocket
in association with one end of said cutter bar and a chain guide
means affixed to the other end of said cutter bar, an endless
cutter chain extending along and supported by said longitudinal
edge portions and extending about and supported by said sprocket
and said guide means, said cutter chain comprising a plurality of
link members some at least of which carry cutting tools, certain
ones at least of said link members each having a body and leg means
projecting from said body, said leg means engaging said
longitudinal edge portions and said guide means, said link members
being joined by pintles, said link members and said pintles being
positioned beyond said longitudinal edge portions of said cutter
bar and beyond the peripheral edges of said guide means, and
engagement surfaces on some of said link members to be drivingly
engaged by said sprocket.
2. The structure claimed in claim 1 wherein each of said link
members which carries a cutting tool has said body, said body being
adapted to mount a cutting tool, said body having a single-link
extension at one end and a pair of spaced link extensions at the
other end, said single-link extension having a transverse
perforation therethrough, said pair of link extensions having
coaxial transverse perforations therethrough, the single-link
extension of each of said link members being adapted to be received
between the spaced pair of link extensions of an adjacent link
member with their respective perforations in alignment, and pintles
passing through said aligned perforations of adjacent link members
to pivotally connect said adjacent link members.
3. The structure claimed in claim 1 wherein said cutter chain
comprises a plurality of cutting-tool-carrying link members
connected together by alternate single-link members, each of said
cutting-tool-carrying link members having a body portion with a
pair of spaced link extensions at both ends, the spaced link
extensions of each pair having coaxial transverse perforations
therethrough, said single-link members each having a transverse
perforation at both ends thereof, the ends of each single-link
member being adapted to be received between a pair of spaced link
extensions of two adjacent cutting-tool-carrying link members with
their respective transverse perforations being in alignment, said
pintles passing through said aligned perforations.
4. The structure claimed in claim 1 wherein said leg means
comprises a leg of inverted T-shaped cross section, said cutter bar
having channels in its longitudinal edge portions, each of said
channels having an channels having an inverted T-shaped cross
section, said legs of said link members having a sliding fit in
said channels.
5. The structure claimed in claim 1 wherein said leg means
comprises a leg of inverted T-shaped cross section, said cutter bar
having channels in its longitudinal edge portions, each of said
channels having a U-shaped cross section, wear strips affixed to
the sidewalls of said channels giving said channels inverted
T-shaped cross sections, said legs of said link members having a
sliding fit in said channels equipped with said wear strips.
6. The structure claimed in claim 1 wherein said leg means
comprises a pair of spaced legs, said pairs of spaced legs being
configured to straddle and slidably engage said longitudinal edge
portions of said cutter bar.
7. The structure claimed in claim 2 wherein said pintles are freely
rotatable in their respective aligned perforations, end portions of
each of said pintles extending beyond the exterior surfaces of the
spaced pair of link extensions through which it passes, means in
association with said end portions of said pintles for maintaining
said pintles in said aligned perforations through which they
pass.
8. The structure claimed in claim 2 wherein said leg means
comprises a pair of spaced legs, said pair of spaced legs being
configured to straddle and slidably engage said longitudinal edge
portions of said cutter bar, said drive sprocket having a
peripheral edge with a plurality of spaced teeth, each of said link
members adapted to pass about said sprocket with its pair of legs
stradling said peripheral edge of said sprocket between said teeth,
and said engagement surfaces comprising the rear surfaces of the
link member body portions which are engaged by one of said teeth,
said last-mentioned tooth being located between said pair of link
extensions on said link member body portion ahead of the
single-link extension of the adjacent link member.
9. The structure claimed in claim 3 wherein said pintles are freely
rotatable in their respective aligned perforations, end portions of
each of said pintles extending beyond the exterior surfaces of the
spaced pair of link extensions through which it passes, means in
association with said end portions of said pintles for maintaining
said pintles in said aligned perforations through which they
pass.
10. The structure claimed in claim 4 wherein said guide means
comprises a member having a peripheral edge a portion at least of
which is substantially semicircular, said peripheral edge having a
channel therein of inverted T-shaped cross section comprising a
continuation of said channels in said cutter bar, said legs of said
link members having a sliding fit in said guide means channel.
11. The structure claimed in claim 5 wherein said guide means
comprises a member having a peripheral edge a portion at least of
which is substantially semicircular, said peripheral edge having a
channel therein of U-shaped cross section, wear strips affixed to
the sidewalls of said guide means channel giving said channel an
inverted T-shaped cross section, said guide means channel and said
guide means wear strips comprising a continuation of said channels
and wear strips of said cutter bar, said legs of said link members
having a sliding fit in said guide means channel equipped with said
guide means wear strips.
12. The structure claimed in claim 6 wherein said cutter bar has
wear strip means along both sides of each of said longitudinal edge
portions, the free ends of each of said pairs of link member legs
being inturned toward each other, said pairs of spaced legs being
configured to straddle said wear strip means and to be slidably
hooked thereabout.
13. The structure claimed in claim 6 wherein said drive sprocket
comprises a disk like body having two faces and a peripheral edge,
said sprocket having a plurality of lugs on at least one of said
faces near said peripheral edge and extending transversely thereof,
said cutter chain passing about said sprocket with said link member
legs straddling the peripheral portion of said sprocket body, said
engagement surfaces being located on said legs and engaged by said
lugs.
14. The structure claimed in claim 6 wherein said guide means
comprises a member having a peripheral edge a portion at least of
which is substantially semicircular, said peripheral edge
comprising a continuation of said longitudinal edge portions of
said cutter bar, said pairs of link member legs being configured to
straddle and engage said peripheral edge of said guide means.
15. The structure claimed in claim 6 wherein said guide means
comprises an idler sprocket affixed to the forward end of said
cutter bar, said sprocket comprising a body portion having two
faces and a peripheral edge, said sprocket having a plurality of
lugs on at least one of its said faces near said peripheral edge,
said cutter chain passing about said sprocket with said link member
legs straddling the peripheral portion of said sprocket body and
located between adjacent ones of said lugs, said engagement
surfaces being located on said legs and engaged by said lugs.
16. The structure claimed in claim 12 wherein said guide means
comprises a member having a peripheral edge a portion at least of
which is substantially semicircular, said peripheral edge of said
guide means comprising a continuation of the longitudinal edge
portions of said cutter bar, said peripheral edge of said guide
means having wear strip means on both sides thereof comprising
continuations of said wear strips on said cutter bar, said pairs of
link member legs being configured to straddle said wear strip means
on said guide means and to be slidably hooked thereabout.
17. A sprocket for engaging the cutter chain of a mining machine or
the like, comprising a rotatable disk like body having two faces
and a peripheral edge, said sprocket having a plurality of lugs on
at least one of said faces near said peripheral edge and extending
transversely thereof.
18. A cutter bar for a mining machine and the like comprising an
elongated member having a top and a bottom surface and longitudinal
edge surfaces, each of said longitudinal edge surfaces being
planar, normal to said top and bottom surfaces and extending from
said top to said bottom surface.
19. The structure claimed in claim 18 including wear strips affixed
to said top and bottom surfaces adjacent said longitudinal edge
surfaces.
20. A link member for a cutter chain and the like comprising a body
portion adapted to mount a cutting tool, said body having a
single-link extension at one end and a pair of spaced link
extensions at the other end, said single-link extension having a
transverse perforation therethrough, said pair of link extensions
having coaxial transverse perforations therethrough, said
single-link extension and said pair of link extensions being so
configured that the single-link extension of one such link element
may be received between the pair of link extensions of another such
link element with said perforations in said single and said pair of
link extensions being coaxial, said body portion having at least
one leg projecting therefrom adapted to slidably engage the
longitudinal edge portions of a cutter bar.
21. The structure claimed in claim 20 wherein said body portion has
a leg of inverted T-shaped cross section adapted to slidably engage
channels of inverted T-shaped cross section in the longitudinal
edge portions of a cutter boar.
22. The structure claimed in claim 20 wherein said body portion has
a pair of spaced legs extending therefrom, said pair of spaced legs
being configured to straddle and slidably engage the longitudinal
edge portions of a cutter bar.
23. The structure claimed in claim 22 wherein said pair of spaced
link extensions are of sufficient length to permit the tooth of a
sprocket to enter therebetween and engage the rear surface of said
body portion ahead of the single link extension of the adjacent
link member.
24. The structure claimed in claim 22 wherein the free ends of said
spaced legs are turned inwardly, and said inturned ends adapted to
be slidably hooked about wear strips on the longitudinal edge
portions of a cutter bar.
25. A link member for a cutter chain and the like comprising a body
portion having a pair of spaced link extensions at both ends, the
spaced link extensions of each pair having coaxial transverse
perforations therethrough, said link member adapted to be connected
to a similar link member by a single-link member having perforated
ends adapted to be received between adjacent pairs of spaced link
extensions with said perforations in said nested parts being
coaxial, said body portion of said link member having at least one
leg adapted to slidably engage the longitudinal edge portions of a
cutter bar.
26. The structure claimed in claim 25 wherein said body portion has
a leg of inverted T-shaped cross section adapted to slidably engage
channels of inverted T-shaped cross section in the longitudinal
edge portions of a cutter bar.
27. The structure claimed in claim 25 wherein said body portion has
a pair of spaced legs extending therefrom, said pair of spaced legs
being configured to straddle and slidably engage the longitudinal
edge portions of a cutter bar.
28. A cutter chain for a mining machine and the like comprising a
plurality of link members joined by pintles, each of said link
members having a body adapted to mount a cutting tool, said body
having a single-link extension at one end and a pair of spaced link
extensions at the other end, said single-link extensions having a
transverse perforation therethrough, said pair of link extensions
having coaxial transverse perforations therethrough, the
single-link extension of each of said link members being located
between the spaced pair of link extensions of an adjacent link
member with their respective perforations in alignment, said
pintles passing through said aligned perforations of adjacent link
members to pivotally connect said adjacent link members, the ends
of said pintles extending beyond the exterior surfaces of said
pairs of spaced link extensions, means in association with said
ends of said pintles, to hold said pintles in place, each of said
pintles being freely rotatable within its respective coaxial
perforations, each of said link members having at least one leg
projecting from said body and adapted to slidably engage the edge
portions of a cutter bar.
29. The structure claimed in claim 28 wherein said pair of spaced
link extensions of each link member is of sufficient length to
permit entrance therebetween of one of the teeth of a drive
sprocket and engagement by said tooth of the rear surface of the
body portion of said link member ahead of the single-link extension
of the adjacent link member.
30. A cutter chain for a mining machine and the like said cutter
chain comprising a plurality of cutting-tool-carrying members
connected together by alternate single-link members, each of said
cutting-tool-carrying link members having a body portion with a
pair of spaced link extensions at both ends, the spaced link
extensions of each pair having coaxial transverse perforations
therethrough, said single-link members each having a transverse
perforation at both ends thereof, the ends of each single-link
member being adapted to be received between a pair of double-link
extensions of two adjacent cutting-tool-carrying link members with
their respective transverse perforations being in alignment, said
pintles passing through said aligned perforations and being freely
rotatable therein, the ends of said pintles extending beyond the
exterior surfaces of said pairs of spaced link extensions, means in
association with said ends of said pintles to hold said pintles in
place in their respective coaxial perforations, each of said
cutting-tool-carrying link members having at least one leg to
slidably engage the edge portions of a cutter bar.
31. A cutter chain for use with a cutter bar and sprocket assembly
and the like, said cutter chain being comprised of a plurality of
link members, pintles for joining adjacent link members, certain of
said link members at least having leg means to engage a chain guide
surface on the periphery of the cutter bar, and said pintles being
located outside of the periphery of the cutter bar chain guide
surface when said chain is mounted on the cutter bar, at least some
of said link members being adapted to receive cutter bits which
extend away from the chain guide surface.
32. The cutter chain of claim 31 in which said leg means comprises
a pair of members adapted to straddle the chain guide surface.
33. The cutter chain of claim 31 in which said leg means comprises
a generally T-shaped member adapted to engage a similarly shaped
channel constituting a part of the chain guide surface.
34. The cutter chain of claim 31 in which said pintles are freely
rotatable with respect to said link members.
35. The cutter chain of claim 31 in which the ends of said pintles
extend beyond the surfaces of the link members they join.
36. The cutter chain of claim 31 in which said leg means are
provided with surfaces to be engaged by the sprocket.
37. An assembly including a cutter bar, a chain and a sprocket,
said chain being comprised of a plurality of link members, said
cutter bar having a chain guide surface at its periphery, certain
at least of said link members having leg means to engage said chain
guide surface, pintles engaging adjacent link members, said pintles
being located beyond the chain guide surface, some of said link
members being adapted to receive cutter bits, and engagement
surfaces on some of said link members to be engaged by said
sprocket.
38. The assembly of claim 1 including chain guide surfaces on said
longitudinal edge portions, said leg means engaging said chain
guide surfaces, and said pintles being beyond said chain guide
surfaces.
39. The assembly of claim 37 wherein said leg means comprises a
depending member having at least one lateral extension, and said
cutter bar chain guide surface comprising a channel in the
longitudinal edge portion of said cutter bar, said channel having a
configuration which conforms with said leg means, said leg means
having a sliding fit in said channel.
40. The assembly of claim 39 including a chain guide means fixed at
one end of said cutter bar, said chain guide means comprising a
member having a peripheral edge a portion at least of which is
substantially semicircular, said peripheral edge having a channel
therein of a configuration which comprises a continuation of said
channel in said cutter bar, said leg means also having a sliding
fit in said chain guide means channel.
41. The sprocket of claim 17 in which said body is provided with a
relief in said peripheral edge between each of said lugs.
42. The cutter bar of claim 18 in which said cutter bar is designed
to receive a chain comprised of a plurality of link members joined
by pintles, some at least of said link members having leg means to
engage said cutter bar, the thickness of said cutter bar being less
than the thickness of said link members.
43. The link member of claim 20 in which said pair of spaced link
extensions is set inwardly from the lateral sides of said link
member sufficient that a pintle may be passed through said coaxial
perforations whereby to join said pair of link extensions with a
said single-link extension with the ends of said pintle stopping
short of or at the lateral sides of said link member.
44. The cutter chain of claim 31 in which said leg means comprises
a depending member having at least one lateral extension, and said
cutter bar chain guide surface comprising a channel on the
periphery of said cutter bar, said channel having a configuration
which conforms with said leg means, said leg means having a sliding
fit in said channel.
45. The link member of claim 20 including a pair of cutting tools
mounted on said body portion, the axes of said cutting tools being
substantially coplanar and substantially normal to the cutter bar,
said cutting tools being disposed about 180.degree. from one
another and each extending outwardly from said body portion, the
axes of said cutting tools being in substantially the same plane as
the said coaxial perforations in the said pair of spaced link
extensions.
46. The assembly of claim 37 in which a said link member adapted to
receive cutter bits is provided with a pair of cutter bits, the
axes of said cutter bits being substantially coplanar and
substantially normal to said cutter bar, said cutter bits being
disposed about 180.degree. from one another and each extending
outwardly from said link member, the axes of said cutter bits and
the axes of said pintles being in substantially the same plane.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a cutter bar, cutter chain and sprocket
assembly for mining machines and the like, and more particularly to
improvements in the individual parts thereof.
2. Description of the Prior Art
Prior art workers have made extensive use of cutter bars as, for
example, in undercutting a seam of material to be mined,
preparatory to loosening a portion of the material by blasting.
Cutter bars have taken various forms depending upon the use to
which they have been put. In some instances, for example, a cutter
bar is rigidly mounted on a mining machine so that the machine
itself must be moved in order to move the cutter bar. In other
instances, a cutter bar is pivotally mounted to a mining machine so
that it may be traversed in the direction of the cut.
In general, a cutter bar comprises an elongated element having a
cutter chain passing about its peripheral portions and driven by
the mining machine to which the cutter bar is affixed. In its usual
form, the cutter bar is so constructed as to have a peripheral
channel or passageway in which the cutter chain rides. For example,
in its most typical form, a cutter bar comprises a pair of parallel
spaced beams having plate members affixed to the top and bottom
surfaces thereof. Edge portions of the plate members define the
sidewalls of the cutter chain channel while the beams themselves
form the channel bottoms. The end of the cutter bar is semicircular
in configuration so that the channel is continuous about the
periphery of the cutter bar. The sides and bottom of the cutter bar
channel are frequently lined with wear strips of hardened steel
which may be replaced as needed.
Cutter chains have taken many forms. In general, however, a cutter
chain comprises a plurality of link members pivoted together by
pintles. Certain of the link members have means for mounting cutter
bits. In the normal cutter chain, there is a plurality of
double-link members providing spaced cheeks interconnected at the
top by blocklike portions or lugs, which are perforated so as to
receive the shanks of cutter bits or cutter bit holders. Alternate
link members are single elements, the ends of which lie between the
cheeks of the double-link members, the various elements being
pivoted together by pintle means. The pintle means are generally
cylindrical elements which pass through perforations in the cheeks
of the double-link members and perforations in the ends of the
alternate single-link members.
Cutter bar-cutter chain assemblies of the general type described
above have been in widespread and successful use for many years.
However, they are characterized by a number of problems and
disadvantages. For example, since each of the double-link members
providing spaced cheeks has its cheeks interconnected at the top by
a block or lug for mounting a cutter bit, the point of contact
between the cutter bit tip and the material being mined lies at a
considerable distance from the line of force on the chain passing
through the chain pintles. As a consequence, there is a strong
tendency for the lug-bearing link members to pivot in a direction
opposite to the cutting direction. This, in turn, creates
considerable vibration and kick in the cutter chain and the
assembly as a whole.
The various cutting forces and vibrational strains of the cutter
bar have a tendency, in time, to cause the cutter bar channel
sidewall to spread apart. This spreading of the channel walls
results in additional vibration of the parts and additional wear
thereof. The undesirable effects created by the spreading of the
channel walls is cumulative because the cutter bar normally
outlasts a number of cutter chains.
Finally, since the cutter chain in prior art structures passes
about the cutter bar in a peripheral channel, and since the pintles
connecting the chain link members lie within the peripheral
channel, the pintles cannot have their ends extend beyond the
outside surfaces of the cheeks of the double-cheeked link members.
As a result, great difficulties have been encountered in devising
means for keeping the pintles in place. Prior art workers have
developed many forms of specifically configured pintles together
with a multitude of keys, clips and other keeping devices. In most
embodiments the pintles are nonrotatively held either by the
single-link elements or the double-link elements with the result
that they were not subject to even wear.
The present invention is directed to improved means for solving the
various problems outlined above.
SUMMARY OF THE INVENTION
The present invention is directed to improved cutter bar, cutter
chain and sprocket assemblies. In general, the cutter bar may
comprise an elongated platelike member. The cutter bar is suitable
mounted on a mining machine. The forward end of the cutter bar has
guide means for the cutter chain. A sprocket is mounted in
association with the rearward end of the cutter bar to drive the
chain about the peripheral edges thereof.
The present invention contemplates a number of embodiments of
cutter chain-cutter bar assemblies. In on embodiment the cutter
chain may be of a type comprising a plurality of link members each
having a body portion adapted to mount a cutter bit. The body
portion has a single-link extension at its forward end and a pair
of spaced link extensions at its rearward end. These link
extensions are so configured that the forward extension of one link
member is adapted to be received between the spaced link extensions
of an adjacent link member. Pintle means pass through the coaxial
perforations in the nested link extensions. Each link member has a
pair of spaced legs adapted to straddle, and slidably engage the
wear strips on the edges of the cutter bar.
A second type of cutter chain bay be used, differing from the first
primarily in that those link members having body portions adapted
to mount cutter bit means have spaced, double-link extensions at
both ends. These link members are joined, in turn, by single-link
members the ends of which are located between the double-link
extensions of adjacent cutter-bit-carrying link members. Again, the
nested extensions are jointed by pintle means passing through
coaxial perforations therein.
In both chain types thus far described, each link member mounting a
cutter bit means may have a pair of spaced legs adapted to straddle
and to slidably engage the peripheral edge portions of the cutter
bar. As indicated above, these edge portions may constitute wear
strips. By virtue of this construction, the entire cutter chain is
exposed to the material being mined and will provide a sweeping
action for the material which has been cut.
When the cutter-bit-mounting links are provided with spaced pairs
of legs, a sprocket may be provided having a plurality of evenly
spaced lateral extensions protruding from both faces thereof and
adapted to engage the edges of the spaced legs of each bit-carrying
link member so as to drive the chain about the periphery of the
cutter bar.
On the other hand, a conventional sprocket may be used with the
first-mentioned type of chain. In such an instance the sprocket
teeth engage the rear surface of the body portion of each link
member between the spaced pair of link extensions thereon.
Whether the link-members-carrying cutter bit means are joined
directly together as in the first-mentioned type of chain or by
means of single-link elements as in the second chain type, each
cutter-bit-carrying link member may be provided with a single leg
of inverted T-shaped cross section. In this instance, the cutter
bar has a peripheral channel of inverted T-shaped cross section.
The legs of the bit-carrying link members are adapted to be
slidably engaged in the cutter bar channel. The driving sprocket
will be of substantially conventional design adapted to engage edge
portions of the T-shaped legs and to drive the chain by virtue of
this engagement.
In all of the embodiments thus far described, the pintle means are
located beyond the peripheral edges of the cutter bar. By virtue of
this construction, the distance from the point of contact between
the cutter bit tip and the material being cut and the line of force
passing through the pintles is greatly reduced. Similarly, the ends
of each pintle may extend beyond the outside surfaces of the link
members it joins. Fastening means may be applied to the pintle ends
and the pintles, themselves, may be freely rotatable and thereby
subject to even wear. The holes in the link members through which
the pintles extend are also subject to wear, thereby further
distributing the wear.
The assembly of the present invention is far simpler in
construction and less expensive to manufacture than prior art
structures. The individual parts are subject to less vibration,
kick and wear, and are caused to wear more evenly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary plan view illustrating one embodiment of a
cutter bar, cutter chain and sprocket assembly of the present
invention.
FIG. 2 is a fragmentary side elevational view of a cutter chain of
the present invention.
FIG. 3 is a fragmentary plan view of the cutter chain of FIG.
2.
FIG. 4 is a perspective view illustrating another mode of
construction of the link members of FIGS. 2 and 3.
FIG. 5 is a fragmentary perspective view illustrating one form of
pintle.
FIG. 6 is a plan view of a retaining ring or spring clip for use
with the pintle of FIG. 5.
FIG. 7 is a fragmentary cross-sectional view taken along the
section line 7--7 of FIG. 1 and showing a cutter bit mounted in the
link member.
FIG. 8 is a view similar to FIG. 7 illustrating another form of
wear strip on the cutter bar and another placement of a cutter bit
in the link member.
FIG. 9 is a fragmentary cross-sectional view similar to FIG. 7
illustrating a modified form of chain link member similar to that
of FIGS. 2 and 3.
FIG. 10 is a fragmentary perspective view of the forward end of a
cutter bar of the present invention.
FIG. 11 is a perspective view illustrating another embodiment of
the cutter chain of the present invention.
FIG. 12 is a fragmentary elevational view illustrating another
embodiment of a cutter chain--cutter bar assembly.
FIG. 13 is a fragmentary cross-sectional view taken along the
section line 13--13 of FIG. 12.
FIG. 14 is a perspective view of cutter chain link members similar
to FIG. 11, but having a single cutter-bar-engaging leg.
FIG. 15 is a fragmentary plan view illustrating a conventional
drive sprocket and another embodiment of the cutter chain of the
present invention.
FIG. 16 is a perspective view of a chain link member of FIG.
15.
FIG. 17 is a plan view of a pair of chain link members illustrating
yet another embodiment of the present invention.
FIGS. 18 and 19 are perspective views of special sprockets which
may be used with certain of the chains of this invention.
FIG. 20 is a fragmentary cross-sectional view similar to FIG. 7
illustrating a chain link member carrying two cutter bits.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the present invention is described in terms of a cutter bar
assembly for a mining machine of the type used in undercutting a
seam of coal of the like, it will be understood by one skilled in
the art that it is within the scope of the invention to apply the
principles thereof to any suitable form of chain-bearing mining
machine. The mining machine itself and the manner in which the
cutter bar is affixed to the mining machine are well known in the
art and do not constitute a part of the present invention.
Reference is made to FIG. 1 wherein an embodiment of the assembly
of the present invention is shown. In FIG. 1, the cutter bar is
generally indicated at 1, the sprocket is generally indicated at 2
and the cutter chain is generally indicated at 3.
The cutter bar 1 comprises an elongated, substantially rectangular
platelike member 4. The longitudinal edges 5 and 6 of the cutter
bar 4 may each be provided with a pair of wear strips. Two such
wear strips are shown at 7 and 8 in FIG. 1. The wear strips may be
made of any suitable material such as hardened steel and may be
fastened to the cutter bar body 4 in any well-known way, inclusive
of bolts, rivets and the like (not shown). The fastening means
should be appropriately countersunk so that the exterior surfaces
of the wear strips are unobstructed. Preferably the wear strips
should be affixed to the cutter bar in such a way as to be readily
replaceable, although the wear strips may constitute integral parts
of the cutter bar if desired.
FIG. 7 shows an exemplary pair of wear strips 7a and 7b. In this
instance, the wear strips are of angle iron cross section so as to
protect both the sides and end portion of the longitudinal edge 5
of the cutter bar. The wear strips should be so sized as to have a
small clearance (indicated at 9) to insure that they may be
properly located on the sides of the cutter bar body. It will be
understood by one skilled in the art that the wear strips 7a and 7b
could be an integral, one-piece structure of channel-shaped cross
section, as illustrated at 7c and 8c in FIG. 10.
FIG. 8 illustrates an alternate form of wear strip. In this
instance, the wear strips 7d and 7e comprise elongated members of
rectangular cross section, affixed to the sides of the cutter bar
body adjacent the longitudinal edge 5.
Referring again to FIG. 1, the sprocket 2 is mounted on the mining
machine at the rearward end of the cutter bar 1. The manner in
which the cutter bar and the sprocket are mounted on the mining
machine is not shown. These mountings may be conventional, and do
not constitute a part of the present invention.
The sprocket comprises the means by which the chain 3 is driven
about the peripheral edges of the cutter bar 1. The sprocket
comprises a disclike element having a plurality of transverse
extensions 10 spaced about its periphery. The extensions 10
protrude from both faces of the disclike element so that they will
engage both legs of the cutter chain link members (as will be
described hereinafter).
The body of the sprocket 2 should have a transverse thickness
approximately equal to the thickness of the cutter bar body 4. The
extensions 10 should be so sized as to enable them to engage the
legs of the cutter chain elements. The extensions 10 may be
integral portions of the sprocket body, elements affixed to either
face of the sprocket body or elements affixed in notches in the
sprocket body. The peripheral portion of the sprocket may have any
suitable configuration. For example, it may be circular as
illustrated in FIG. 1, or it may be relieved (as shown by the
dotted line 11) so as to have a scalloped configuration.
FIGS. 2, 3 and 7 illustrate one embodiment of the cutter chain of
the present invention. The cutter chain is made up of a plurality
of substantially identical link members. One such link member is
generally indicated at 12 in FIGS. 2, 3 and 7. The link member
comprises a body portion 13 having a single forward link extension
14 and a pair of spaced rearward link extensions 15 and 16. It will
be noted that the forward link extension 14 and the rearward link
extensions 15 and 16 are in line with the body 13.
The forward link extension 14 has a transverse perforation 17. The
rearward link extensions 15 and 16 have coaxial transverse
perforations 18 and 19, respectively.
The body 13 has a bottom surface 20 which may be planar if the
sprocket 2 has a noncircular peripheral configuration. When the
sprocket 2 has a circular peripheral configuration, the central
portion of the bottom surface 20 may have an arcuate relief (as
shown in FIGS. 1, 2 and 7) so as to conform to the sprocket edge.
When the arcuate relief extends the full width of the bottom
surface 20, the link member will ride on bottom surface portions
20a and 20b (FIG. 2) when in straight travel. If the relief is of a
width substantially equal to the thickness of the sprocket body,
shoulders 20c and 20d (FIG. 7) will be formed extending the length
of the bottom surface of the link member and comprising bearing
surfaces when the link member travels along the straight,
longitudinal edges of the cutter bar.
The chain link body 13 also has a pair of spaced legs 21 and 22
extending therefrom. As shown in FIG. 7, the distance between the
legs 21 and 22 is such as to permit a sliding fit of the cutter bar
and wear strips therebetween. The legs 21 and 22 have inwardly
directed extensions 23 and 24, respectively, so as to render the
link member captively mounted on the cutter bar by virtue of the
interaction between the extension 23 and the wear strip 7b and the
extension 24 and the wear strip 7a.
The forward and rearward edges of the legs 21 and 22 are relieved.
Reliefs 25 and 26 on leg 22 are illustrated in FIG. 2. The leg 21
(not shown in FIG. 2) will be relieved in an identical manner.
The purpose of the relief is clearly shown in FIG. 1. The reliefs
are so angled as to serve as engagement surfaces for the sprocket
extensions 10 whereby the extensions can engage and drive the link
members about the cutter bar. It will be understood by one skilled
in the art that the reliefs on those link member legs on the other
side of the sprocket will similarly be engaged by sprocket
extensions 10 on that side of the sprocket.
In FIG. 8, the link body 13 is substantially identical to that of
FIG. 7 and is provided with identical legs having the same index
numerals. The interaction of the extended leg portions 23 and 24
and the wear strips 7e and 7d is the same. The only difference
between the embodiment of FIG. 8 and that of FIG. 7 is the fact
that the bottom surface 20 of the body 13 rides directly on the
edge 5 of the cutter bar body 4 and the outermost edges of the wear
strips 7d and 7e.
In FIGS. 2 and 3, adjacent link members are fragmentarily
illustrated at 12a and 12b. These link members are substantially
identical to the link member 12 and like parts have been given like
index numerals followed by a and b, respectively. As will be
evident from FIGS. 2 and 3, the forward link extensions 14 of the
link 12 will nest between the spaced rearward link extensions 15a
and 16a of link member 12a. The perforations 17, 18a and 19a of the
link extensions 17, 15a and 16a, respectively, will be coaxial and
will accept a cylindrical pintle 27.
Similarly, the link extension 14b of link member 12b will nest
between the rearward link extensions 15 and 16 of link member 12.
The perforations 17b, 18 and 19 in link extensions 14b, 15 and 16
respectively, will be coaxial and will accept a cylindrical pintle
28. In this way, adjacent link members may be joined to form an
endless cutter chain.
Since the pintle-carrying link extensions are affixed directly to
the body portions of the chain link members and since the pintles
do not ride in a continuous channel on the cutter bar, the ends of
the pintles 27 and 28 may extend beyond the exterior surfaces of
link extensions 15a-16a and 15-16, respectively. This in turn,
enables the use of fastening means at the ends of the pintles.
Thus, the pintles may have a diameter such as to be freely
rotatable in the perforations in the link extensions, resulting in
even wear of the pintles and far longer pintle life.
Any suitable means may be used to hold the pintles in their proper
place. For example, pintle 27 in FIG. 2 is illustrated as having a
nut 29 threaded thereon. Pintle 28 in FIG. 2 is illustrated as
having a transverse perforation 28a adapted to receive a roll pin
30.
In FIG. 3, pintle 27 is illustrated as having a head 31 at one end,
and a roll pin 32 at the other. Pintle 28 is illustrated as being
held in place by spring clips or retaining means 33 at both
ends.
The latter arrangement is more clearly illustrated in FIGS. 5 and
6. As shown, the pintle 28 is provided near its end with an annular
groove 34. The annular groove is adapted to receive the retaining
ring or spring clip 33 of FIG. 6. The outside diameter of the ring
33 is greater than the diameter of the pintle and the diameter of
the perforations through which the pintle extends. The inside
diameter of the ring 33 is less than the diameter of the pintle and
substantially equivalent to the diameter of the groove or notch 34.
The ring 33 is split so as to form an opening between its ends. The
width of the opening is less than the diameter of the notch or
groove 34. The retaining ring will be made of resilient metal or
the like and can be forced into position in the groove 34.
From the above it will be evident to one skilled in the art that
the pintles 27 and 28 may be provided with any of the above
described retaining means, or any combination of them.
The spaced rearward link extensions of each chain element may be
provided with rearwardly facing planar surfaces. Such surfaces are
illustrated at 34 and 35 on link extensions 15 and 16,
respectively, and at 34a and 35a on link extensions 15a and 17a,
respectively. The forward end of the link element 12 may be
provided with planar surfaces 36 and 37 on either side of the link
extensions 14. Similarly, the link element 12b may be provided with
planar surfaces 36b and 37b on either side of link extension 14b.
When the cutter is passing through its straight flights on either
side of the cutter bar 1, the planar surface 34-35 and 34a-35a on
the rearward link extensions will coact with the planar forward
surfaces 36b-37b and 36-37, respectively, to rigidify the cutter
chain. It is also within the scope of the invention to configure a
portion of the forward surfaces 36-37 or 36b-37b as shown in FIG. 1
at 37c and 37d. This configuration aids in the prevention of the
accumulation of fines and foreign materials between the rearward
link extensions of one chain element and the forward faces of the
adjacent chain element.
The type of cutter bit or cutter bit adapter carried by the body 13
does not constitute a limitation on the present invention. For
purposes of an exemplary showing, the body 13 is illustrated in
FIGS. 2, 7 ans 8 as carrying a cutter bit of the general type set
forth in U.S. Pat. No. 3,114,537. It will be understood, however,
that other types of cutter bits or cutter bit adapter assemblies
may be used. For example, the link members may be adapted to mount
the pick-type conical cutter bits, in extensive use today, and
exemplified by U.S. Pat. Nos. 3,397,012 and 3,397,013. Similarly,
nonrotatable cutter bits made from round stock may be used. Such
cutter bits are taught in the copending application entitled CUTTER
BITS AND MEANS FOR MOUNTING THEM, Ser. No. 753,398, filed Aug. 19,
1968 in the name of the same inventor.
For purposes of an exemplary illustration, the body 13 is shown as
having a shank-receiving perforation 38 and a transverse hole 39
partially intersecting the shank-receiving perforation. The
transverse hole 39 is adapted to receive a resilient retaining
means, which may be of the type described in the above-mentioned
U.S. Pat. No. 3,114,537. The retaining means comprises a pin 40, at
least the ends of which are surrounded in bodies of resilient
material 41. The retainer may have a longitudinal key 42 and the
transverse hole 49 may have a longitudinal keyway 43. Interaction
of the key 42 and the keyway 43 will maintain the resilient
retainer in its proper orientation, with the pin 40 extending part
way into the shank-receiving perforation 38.
The cutter bit, generally indicated at 44, comprises a head 45 and
a shank 46. The head 45 may be provided with a hard cutting tip
45a, gauge-determining abutment surfaces 47 and a surface 48 for
engagement by a bit removal tool. The shank 46 has a relief 49 at
its bottom rearward edge and a substantially hook-shaped notch 50
in its rear surface. When the shank of the cutter bit is inserted
in the shank-receiving perforation 38, the relief surface 49 will
cause the retainer pin 40 to move rearwardly and out of the
shank-receiving perforation. When the cutter bit is in its fully
seated position, the retainer pin 40 will engage the hook-shaped
notch 50 in the cutter bit shank to maintain the cutter bit shank
in its seated position.
In the usual practice, the cutter bits on the cutter chain are
oriented at various angles so that a cut is made of sufficient
width to permit passage of the cutter bar-cutter chain assembly. To
accomplish this, the top surface of the body 13 may be
appropriately configured and the shank-receiving perforation 38 and
transverse hole 29 may be properly oriented. In FIG. 7, for
example, the cutter bit 44 is shown lying in substantially the same
plane as the cutter bar 1. However, the cutter bit 44 may be
oriented anywhere along the dotted arcuate line A. FIG. 8, for
example, illustrates the cutter bit 44 lying at an angle of about
45.degree. to the transverse axis of the cutter bar 1. The
placement of the cutter bit may be varied throughout an arc of
about 180.degree.. It is also within the scope of the present
invention to make the body 13 of the chain element of such size as
to enable it to mount more than one cutter bit at varying
angularities.
FIG. 10 is a perspective view illustrating the forward end of the
cutter bar 1. As indicated above, for purposes of an exemplary
showing the cutter bar body 4 is illustrated as having wear strips
7c and 8c affixed to its longitudinal edges, the wear strips having
a U-shaped cross-sectional configuration. The forwardmost end of
the cutter bar comprises a shoe 51, one end of which is affixed to
the forward end of the cutter bar body 4. The shoe 51 may be
affixed to the cutter bar body by welding or the like, or it may be
removably affixed by bolts or other suitable means (not shown). On
the other hand, the shoe may constitute an integral part of the
cutter bar. The forward end of the shoe 51 is substantially
semicircular. The peripheral edges of the shoe are protected by
wear strip means generally indicated at 52. The wear strip means 52
may be of any of the types set forth above, and removably affixed
to the shoe by conventional means. Preferably, however, the wear
strip means 52 comprises an integral portion of the shoe 51. This
is true because the wear strip portion 52 will be subjected to
greater stresses than wear strip means along the longitudinal edges
of the cutter bar and, if removably affixed, will have a tendency
to be broken off in time, during the cutting operation. That
portion of the wear strip means 52, passing about the semicircular
edge of the shoe 51 will be narrower than the straight portion (as
illustrated in FIG. 10) to permit the leg extensions 23 and 24 to
pass thereabout.
It will be understood by one skilled in the art that it would be
within the scope of the invention to use a sprocket at the forward
end of the cutter bar rather than the shoe 51. For example, the
sprocket could be identical to the one shown in FIG. 1, except that
it would be an idler sprocket rather than a driven one. For
purposes of the present discussion, FIG. 1 could be considered the
forward end of the cutter bar 1 with the sprocket 2 rotatively
mounted thereto by means not shown.
The operation of the cutter bar, cutter chain and sprocket assembly
of the present invention will be obvious in view of FIG. 1. If the
cutter chain 3 is caused to move in a cutting direction (shown by
arrow B), the individual chain elements will move forwardly along
the wear strips 7 on the cutter bar and will be captively held
thereon by the inner action of the chain element legs and the wear
strips. At the rearward end of the cutter bar 1, the chain elements
will pass forwardly to the sprocket 2 and the link element legs
will straddle the sprocket and be engaged by the transverse
extensions 10. In this manner, the chain elements will be driven by
the sprocket and will pass forwardly along the other edge of the
cutter bar. Again, the chain elements will be captively held to the
edge of the cutter bar by the inner action of their legs and the
wear strips 8. The chain will be guided about the forward end of
the cutter bar by suitable means such as the shoe 51 or an idler
sprocket, as described above.
FIG. 4 illustrates another embodiment of a cutter chain link
member. The link member of FIG. 4 differs from the member 12 of
FIGS. 2 and 3 primarily in that it is made up of three pieces
rather than being an integral, one-piece unit. The link element of
FIG. 4, generally indicated at 54 is made up of a body member 55
and side members 56 and 57. The body member 55 has a rounded
forward end constituting a single-link extension equivalent to the
forward link extensions 14 and 14b of FIGS. 2 and 3. The body
member 55 also has a bottom surface (not shown) equivalent to the
bottom surface 20 in FIG. 2. A shank-receiving perforation 58 and a
transverse perforation 59 may also be provided in the body member
55.
The side elements or members 56 and 57 are mirror images of each
other. They have rearward extensions 60 and 61 equivalent to the
space link extensions 15 and 16 in FIG. 3. The extended portions 60
and 61 are provided with coaxial perforations 62 and 63,
respectively, for the receipt of a pintle. The space between the
extended portions 60 and 61 is such as to receive the forward end
of the body of an adjacent link member. Each of the side members 56
and 57 may have perforations (one of which is shown at 64) which
are coaxial with and comprise extensions of the transverse
perforation 59 in the body member 55, for the receipt of a
resilient retaining means.
The side members 56 and 57 have downwardly depending portions 56a
and 57a, respectively, which are equivalent to the legs 21 and 22
of the link member 12 of FIGS. 2, 3 and 7. The leg portions 56a and
57a have inwardly turned portions 65 and 66 equivalent to the
inward extensions 23 and 24 of FIG. 7. The legs 56a and 57a are
also provided with reliefs, three of which are shown at 67, 68 and
69. These reliefs are equivalent to those shown at 25 and 26 in
FIG. 2. Finally, the side members 56 and 57 have rearward surfaces
70 and 71 equivalent to the surfaces 34 and 35 in FIGS. 2 and 3, as
well as forward surfaces 72 and 73 equivalent to the forward
surfaces 36 and 37 in FIGS. 2 and 3.
The functioning of the link member of FIG. 4 will in every way, be
identical to the link members illustrated in FIGS. 2 and 3. The
side members 56 and 57 may be permanently or removably affixed to
the body member 55 by any suitable means.
FIG. 9 is a cross-sectional view similar to FIGS. 7 and 8. In FIG.
9, the body portion 4 of the cutter bar 1 is shown carrying a link
member, generally indicated at 74. The link member has a body
portion 75 and legs 76 and 77.
The link member 74 may be considered as being substantially
identical to the embodiment shown in FIGS. 2 and 3, or the
embodiment shown in FIG. 4. The difference lies primarily in the
fact that the legs 76 and 77 do not have inwardly extending leg
portions equivalent, for example, to those shown at 23 and 24 in
FIGS. 7 and 8. For purposes of an exemplary showing, the peripheral
edge of the cutter bar 1 is illustrated as not having wear strips.
It will be understood by one skilled in the art that wear strips of
any of the types described above could be applied in the same
manner shown in FIGS. 7, 8 and 10.
FIG. 11 is a perspective view illustrating another embodiment of a
cutter chain of the present invention. A cutter-bit-carrying link
member is generally indicated at 78. The link member 78 has a body
portion 79, a pair of legs 80 and 81 having inwardly turned
portions 82 and 83 respectively. The forward surfaces of the legs
are relieved as at 84 and 85. The rearward surfaces of the legs are
similarly relieved (one such relief shown at 86).
Again, while the link member 78 may be adapted to carry any of the
above-discussed types of cutter bits or cutter bit adapted for
purposes of an exemplary showing the link is illustrated as having
a shank-receiving perforation 87 and a transverse perforation 88
for the receipt of a resilient retaining means. As thus far
described, the embodiment of FIG. 11 is generally similar to that
of FIGS. 2 and 3. The primary difference lies in the fact that the
link member 78 carries a pair of spaced link extensions at both
ends. The forward link extensions are illustrated at 89 and 90,
while the rearward extensions are shown at 91 and 92. The forward
extensions have coaxial perforations, one of which is shown at 93.
The rearward extensions have coaxial perforations 94 and 95. It
will be understood that the link member 78 could be a one-piece
structure or could be made up of a number of pieces of the same
manner set forth with respect to FIG. 4.
Adjacent bit-carrying links 78 are adapted to be joined by
single-link members, one of which is generally indicated at 96. The
single-link member has perforations at each end (one of which is
shown at 97). The ends of the single-link member 96 are adapted to
nest between the spaced pairs of link extensions on adjacent
bit-carrying link members and to be joined thereto by pintle means
passing through the coaxial perforations in the space-link
extensions and the perforations in the ends of the single-link
members. An exemplary pintle is shown at 93a.
The above-described embodiment has several advantages. For example,
when compared to the embodiment of FIGS. 2 and 3, the cutter chain
of FIG. 11 will be seen to have twice as many joints. Thus, it is
more flexible and the pintles will remain nearer the peripheral
edge of the guide means at the forward end of the cutter bar as the
chain passes thereabout.
Forces are at play in the embodiment of FIGS. 2 and 3 which will
tend to make the chain kick but these are compensated for by the
arrangement of the chain members. For example, if the chain of FIG.
2 is moved in the direction indicated by arrow C, the forward end
of the link member 12 will tend to rise in the direction of arrow
D, while the rearward end will tend to lower in the direction of
arrow E. However, at the same time, the rearward end of link member
12a will tend to lower in the direction of arrow F while the
forward end of link member 12b will tend to rise in the direction
of arrow G. Thus, the opposite forces indicated by arrows F and D
and arrows E and G will tend to cancel each other and reduce the
amount of kick displayed by the embodiment of FIG. 2. In any of the
embodiments of the present invention wherein the cutter chain
includes single-link members of the type shown at 96 in FIG. 11,
the chains will be more flexible and the pintles will ride nearer
the peripheral edge of the forward guide means of the cutter
bar.
FIGS. 12 and 13 illustrate yet another embodiment of the cutter
bar-cutter chain of the present invention. In this embodiment,
three identical links are illustrated at 98, 99 and 100. Each link
member has a single forward extension 98a, 99a and 100a. Similarly,
each link member has a pair of spaced link extensions one each of
which is shown at 98b, 99b and 100b. The various links are joined
by pintle means 101, 102 and 103.
As thus far described, the link members 98, 99 and 100 are
substantially similar to the link members 12, 12a and 12b of FIG.
2. Again the link members may carry any suitable type of cutter bit
or adapter and retaining means (not shown).
The cutter bar 104 may be of any suitable construction and has
about its peripheral edges a channel having an inverted T-shaped
cross section. It will be understood by one skilled in the art that
the channel could have a U-shaped cross section which could be
modified to a T-shaped cross section by the placement of wear
strips along the channel sides. One such wear strip is indicated in
dotted lines at 106 in FIG. 13. Similarly, the bottom of the
channel could be extended and provided with a wear strip, as
indicated in dotted lines at 107.
The link members 98, 99 and 100 differ from those of FIGS. 2 and 3
primarily in that each is provided with a single leg (108, 109 and
110) rather than a pair of legs as shown in FIG. 2. Referring to
FIG. 13, it will be noted that the leg 108 has an inverted T-shaped
configuration and is located centrally of the body of the link
member 98. Thus, the configuration of the leg 108 and the
configuration of the channel 105 are such as to slidably but
captively maintain the link element 98 in proper position with
respect to the peripheral edges of the cutter bar 104. The other
legs 109 and 110 are similarly configured and similarly positioned
on the link members 99 and 100, respectively.
The forward and rearward edges of the legs 108, 109 and 110 are
relieved as at 108a-108b, 109a-109b, and 110a-110b. These edges are
adjusted to be engaged by sprocket means located in association
with the rearward end of the cutter bar. When a chain of the type
shown in FIGS. 12 and 13 is used, the forward end of the cutter bar
will be provided with suitable guide means as for example a shoe
generally similar to that shown in FIG. 10, but having a matching
channel of inverted T-shaped cross section. When such a shoe is
used, FIG. 13 could also be considered a cross-sectional view
through the peripheral edge portion of the shoe.
In the embodiment of FIG. 12, it would be within the scope of the
invention to configure the double-link extensions 98b, 99b and 100b
in the same manner shown with respect to the double-link extensions
in FIG. 2, to rigidify the chain during its straight flights.
Similarly, the forward faces of link members 98, 99 and 100 could
be configured as shown in FIG. 1.
In like manner, it would be within the scope of the invention to
provide each of the link members 98, 99 and 100 with pairs of
spaced link extensions at both ends, as described with respect to
FIG. 11. In such an instance, additional single-link members would
be required.
This is illustrated in FIG. 14. A cutting-tool-carrying link member
is generally shown at 111 having a body portion 112, forward link
extensions 113 and 114, and rearward link extensions 115 and 116.
The link member 112 is provided with a single leg 117 similar to
the legs 108, 109 and 110 of FIG. 12. A single-link member is
illustrated at 118, joined to the link member 111 by a pintle
119.
Suitable sprockets for driving the chains of FIGS. 12-14 are shown
at 150 and 152 in FIGS. 18 and 19.
FIGS. 15 and 16 illustrate yet another embodiment of the cutter
chain of the present invention. A conventional drive sprocket is
generally indicated at 120. The sprocket has a plurality of spaced
teeth 121 with intermediate peripheral edge portions 122 extending
therebetween.
In FIG. 15, three identical link members 123-125 are shown passing
about the sprocket 120. For purposes of an exemplary showing, FIG.
16 comprises a perspective view of link 124.
The link members of this embodiment are generally similar to those
shown in FIGS. 1 and 2. The link 124 has a body portion 125 with a
single-link extension 126 at its forward end and a pair of spaced
link extensions 127 and 128 at its rearward end. The link extension
126 has a pintle-receiving perforation 126a. Similarly the link
extensions 127 and 128 have coaxial pintle-receiving perforations
127a and 128a. By virtue of this construction, the link elements
123-125 can be joined together by pintle means 129 and 130. Again,
the pintle means 129 and 130 may be freely rotatable in their
respective pintle perforations and may extend beyond the outside
surfaces of the spaced link extension with means at their ends for
holding the pintles in place.
The body 125 of the link member 124 will have means (not shown) for
mounting a cutting tool of any suitable type.
The link member body 125 also has a pair of spaced legs 131 and 132
substantially similar to the spaced legs illustrated in FIGS. 1 and
2. It is within the scope of the invention to provide the legs 131
and 132 with inturned portions, one of which is illustrated at 133
in FIG. 15. These inturned leg portions will serve the same purpose
as described with respect to the leg portions 23 and 24 in FIGS. 7
and 8.
The rearward edges of the spaced pair of link extensions 127 and
128 may be planar as at 127b and 128b. The forward surfaces of the
body 125 will also be planar as at 134 and 135. The forward
surfaces will also have a concave portion, one of which is shown at
136. In this way, adjacent link members will be free to pivot about
their respective pintles as they pass around the sprocket 120, but
will be stabilized during their straight flights by the interaction
of the rear edges of the spaced pair of link extensions of one link
member and the straight portions of the forward edges of the
adjacent link member. This interaction is similar to that described
with respect to FIGS. 1 and 2.
The primary difference between the embodiment of FIGS. 15 and 16
and the embodiment of FIGS. 1 and 2 lies in the fact that the rear
surface 125a of the body portion 125 is spaced by a greater
distance from the forward link extension of the adjacent link
member. This permits entrance therebetween of a sprocket tooth 121,
as illustrated in FIG. 15. The sprocket tooth may thus engage the
surface 125a and drive the link member in a cutting direction. The
bottom surfaces of the forward link extension 126 and the body 125
are supported on a peripheral edge portion 122 of the sprocket
120.
In all of the embodiments thus far described, it will be noted that
the pintle means are located beyond the peripheral edges of the
cutter bar. Thus, in all of the embodiments the ends of the pintle
means are free to extend beyond the sides of the link members they
join and thus the pintle means may be held in place by any of the
various means described with respect to FIGS. 2, 3, 5 and 6. It
will be immediately evident that the distance between the point of
contact between the tip of the cutter bit carried by the link
members and the material being cut (i.e. the point of applied
force) and the line of force passing through the pintles (i.e. the
driving force) has been greatly reduced in each embodiment. All of
the assemblies thus far described will be characterized by improved
performance and longer service life.
FIG. 17 illustrates a modification of the cutter chain link
elements which may be applied to any of the previously described
embodiments.
The Figure illustrates two chain link elements 137 and 138. The
link element 137 may have any suitable type of shank-receiving
perforation as at 139. The link element may also have any of the
leg means (not shown) described with respect to the previous
embodiments.
A forward link extension is shown at 140 and a pair of rearward
link extensions is illustrated at 141 and 142. The link extensions
140-142 are suitably perforated to accommodate pintle means.
The link element 138 is identical to link element 137 and has a
forward extension 143, rearward extensions 144 and 145 and a
shank-receiving perforation 146.
In the structure of FIG. 17, it will be noted that the rearward
extensions 141-142 and 144-145 are suitably spaced to receive
therebetween the forward extension of an adjacent link member. This
forward extension 143 is illustrated as being positioned between
rearward extensions 141 and 142. A pintle 147 passes through
coaxial perforations in link extensions 141, 142 and 143
effectively joining link elements 137 and 138. In addition,
however, the rearward extensions 141-142 and 144-145 are spaced
inwardly on the sides of their respective link elements 137 and
138. This enables the ends of pintle 147 to extend beyond the
outside surfaces of extensions 141 and 142 while at the same time
being protected by the body portions of the link elements 137 and
138. Again, the pintle 147 may be freely rotatable and may be held
in place by any suitable means such as, for example, any of those
taught with respect to FIGS. 2, 3, 5 and 6. For purposes of
illustration, roll pins 30 are shown in FIG. 17.
FIG. 20 is a fragmentary cross-sectional view similar to FIG. 7 and
illustrates an advantage of the present invention. The cutter bar
and wear strip members are the same as those in FIG. 7 and like
parts have been given like index numerals. For purposes of an
exemplary illustration, a link member 153, similar to the link
members 137 and 138 of FIG. 17, is shown mounted on the cutter bar.
The link member 153 has leg portions 154 and 155 engaging and
straddling the wear strips 7a and 7b. The link member has a forward
extension 156 carrying a pintle 157. Rearward extensions 158 and
159 of an adjacent link member are shown in cross section.
The structure of the present invention enables the provision of a
link member carrying two cutter bits in extreme cutting positions,
substantially normal to the cutter bar. Bits 160 and 161 are shown
in these positions. The axes of the bits are coplanar. It will be
understood by one skilled in the art that the link member 153 will
be provided with two transverse shank-receiving perforations,
located one behind the other.
Heretofore, when bits have been placed in these extreme positions,
the block or link member carrying them has been subjected to
particularly severe wear and has imparted severe wear to the cutter
bar. This is true because the bits, by virtue of their positions,
demonstrate both twist and kick.
In accordance with the present invention, however, it is possible
to locate the axes of the bits 160 and 161 in substantially the
same plane as the axis of the pintle 157. The tendency for the
block to twist is greatly reduced by virtue of the fact that the
bits 160 and 161 are oppositely disposed. The tendency for kick is
substantially eliminated by virtue of the fact that the applied
force (i.e., the driving force on the chain) passes through the
axes of the bits and the axis of the pintle and is in line with the
force applied to the bits by the material being cut. Any of the
link structures of the present invention may be substituted for the
one shown in FIG. 20 and will be characterized by the same
advantages.
Modifications may be made in the invention without departing from
the spirit of it.
* * * * *