U.S. patent application number 10/256816 was filed with the patent office on 2004-04-01 for mechanically attached tip assembly.
Invention is credited to Burdick, Jon S., Cox, Matthew K., Erickson, Kenton L., Gale, Preston L., Holtz, Thomas D., Livesay, Richard E., Umbach, Brian B..
Application Number | 20040060207 10/256816 |
Document ID | / |
Family ID | 32029368 |
Filed Date | 2004-04-01 |
United States Patent
Application |
20040060207 |
Kind Code |
A1 |
Livesay, Richard E. ; et
al. |
April 1, 2004 |
Mechanically attached tip assembly
Abstract
A tip assembly has a replaceable wear member mounted to an
adapter carried on the cutting edge of an implement of an
earth-working machine. The adapter has an external surface formed
to engage a complementary internal cavity of the wear member and
includes a pair of transversely spaced sides at least one of the
transversely spaced sides include a guide arrangement and a
retainer pocket positioned therein. The wear member has a body with
an exterior ground-engaging surface, a mounting end, an adapter
receiving cavity and at least one ear extending from the mounting
end. The at least one ear is configured to be received by the guide
arrangement when the wear member is positioned on the adapter.
Inventors: |
Livesay, Richard E.;
(Peoria, IL) ; Burdick, Jon S.; (Biscayne Park,
FL) ; Cox, Matthew K.; (Peoria, IL) ;
Erickson, Kenton L.; (Peoria, IL) ; Gale, Preston
L.; (Mackinaw, IL) ; Holtz, Thomas D.;
(Peoria, IL) ; Umbach, Brian B.; (Peoria,
IL) |
Correspondence
Address: |
CATERPILLAR INC.
100 N.E. ADAMS STREET
PATENT DEPT.
PEORIA
IL
616296490
|
Family ID: |
32029368 |
Appl. No.: |
10/256816 |
Filed: |
September 27, 2002 |
Current U.S.
Class: |
37/451 |
Current CPC
Class: |
E02F 9/2833 20130101;
E02F 9/2825 20130101 |
Class at
Publication: |
037/451 |
International
Class: |
E02F 009/28 |
Claims
What is claimed is:
1. A tip assembly comprising: an adapter having a forward end
portion, a pair of spaced surfaces, and a pair of spaced sides, at
least one of said spaced sides having a retainer pocket positioned
therein and a guide arrangement positioned thereon; and a wear
member having a body with an exterior ground-engaging surface, an
adapter receiving cavity, a mounting end, and at least one ear
extending from said mounting end, said cavity being configured to
receive said adapter thereinto, said one ear being configured to be
received in relationship with said guide arrangement.
2. The tip assembly of claim 1 wherein of said guide arrangement
includes a raised rib.
3. The tip assembly of claim 2 wherein said guide arrangement
includes an upper and lower raised shoulder positioned on each side
of said raised rib.
4. The tip assembly of claim 3 wherein said one ear is positioned
between said upper and lower raised shoulders and over said raised
rib when said wear member is positioned on said adapter.
5. The tip assembly of claim 3 wherein said retainer pocket has a
bottom surface lying along a first plane, said at least one spaced
sides lying along a second plane outboard of said first plane, said
raised rib includes a raised surface lying along a third plane
outboard of said second plane, and said upper and lower raised
shoulder each include an outer edge lying along a fourth plane
outboard of said third plane.
6. The tip assembly of claim 2 wherein said wear member further
includes a through-hole located in said body, said through-hole
extending from said ground engaging surface to said adapter
receiving cavity and alignable with said retainer pocket in said
adapter.
7. The tip assembly of claim 6 wherein said raised rib has a pair
of spaced sides being spaced apart a predetermined distance and
wherein said retainer pocket defines a bore having a predetermined
diameter, said bore extending radially outward at a distance
greater than said predetermined distance so as to be disposed
outboard of said spaced sides of said raised rib.
8. The tip assembly of claim 7 wherein said one ear includes a
groove facing the adapter receiving cavity, said groove includes a
pair of opposed sides and an inner surface, said spaced sides and
said outer surface of said raised rib are disposed in close
abutting relationship to said opposed sides and said inner surface
of said groove, respectively when said wear member is positioned on
said adapter.
9. The tip assembly of claim 1 including a retainer for selectively
retaining said wear member to said adapter.
10. The tip assembly of claim 9 wherein said retainer includes a
barrel member adapted for engagement with said adapter to prevent
the rotation of said barrel member upon the application of a
retaining force thereto.
11. The tip assembly of claim 10 wherein said barrel member
includes a threaded portion and wherein said retainer includes a
fastening member having a threaded stud portion on one end thereof
and a tool socket in the other end thereof, and said fastening
member is adapted to be threadably engageable with said threaded
portion of said barrel member.
12. The tip assembly of claim 11 wherein said barrel member
includes a tapered socket and wherein said fastening member
includes a tapered portion that lockingly engages said tapered
socket in said barrel member.
13. The tip assembly of claim 12 wherein said barrel member
includes a pair of spaced surfaces positioned on a second end
thereof that align with a pair of spaced sides on a raised rib of
said adapter.
14. A wear member for a tip assembly, said wear member comprising:
an exterior ground-engaging surface; a mounting end; a pair of ears
extending from said mounting end; an adapter receiving cavity
opening through said mounting end, said adapter receiving cavity
including a forward end portion a pair of spaced surfaces and a
pair of spaced sides; and a through-hole extending from said
exterior ground-engaging surface to at least one of said spaced
sides.
15. The wear member of claim 14, wherein at least one of said pair
of ears including a groove positioned thereon facing toward said
adapter receiving cavity opening and extending from said through
hole along a central axis.
16. The wear member of claim 15, wherein said groove includes a
pair of opposite side surfaces and a transverse surface.
17. The wear member of claim 16, wherein said other ear includes a
groove positioned thereon facing toward said adapter receiving
cavity opening and extending from said through hole along a central
axis.
18. The wear member of claim 14, wherein said through hole is a
slot.
19. The wear member of claim 18, including a through hole extending
from said exterior ground-engaging surface to the other one of said
spaced sides.
20. An adapter for a tip assembly, said adapter comprising: a
forward end portion; a pair of spaced surfaces; a pair of spaced
sides; and wherein said at least one of said spaced sides having a
retainer pocket positioned therein and a guide arrangement
positioned thereon.
21. The adapter of claim 20, wherein of said guide arrangement
includes a raised rib.
22. The adapter of claim 21, wherein said guide arrangement
includes an upper and lower raised shoulder positioned on each side
of said raised rib.
23. The adapter of claim 22, wherein said retainer pocket has a
bottom surface lying along a first plane, said at least one spaced
sides lying along a second plane outboard of said first plane, said
raised rib includes a raised surface lying along a third plane
outboard of said second plane, and said upper and lower raised
shoulder each include an outer edge lying along a fourth plane
outboard of said third plane.
24. The adapter of claim 23, being a one of a bolt on and a weld on
type adapter.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to a tip and an
adapter assembly for an earth working implement such as a bucket
and, more particularly, to a novel interface between a tip and an
adapter and the mechanical retainer therefore.
BACKGROUND
[0002] Excavating tooth assemblies have long been mounted along the
digging edge of buckets used on earth working machines, such as
excavators, backhoes and the like, to break up the ground and
enhance the digging operation. The tooth assemblies are ordinarily
formed of a plurality of parts to reduce the size of the outerwear
member that frequently needs to be replaced. In general, a tooth
assembly comprises an adapter, a wear member, and a retainer
typically in the form of a pin to secure the wear member to the
adapter. The adapter has a rear end, which is secured to the
digging edge of an excavator bucket and a forwardly projecting nose
for mounting the wear member. The wear member is typically a
tapered wedge-shaped member provided with a forward digging edge
and a rearward opening socket adapted to be received over the
adapter nose.
[0003] The tooth assemblies are commonly subjected to heavy loading
by large forces applied in a wide variety of directions. As a
result, the wear member must be firmly secured to the adapter to
withstand the applied forces, but yet be easily removed and
installed for effective replacement in the field. Further, wearing
of the tooth components causes looseness in the connection which in
certain circumstances can result in the retainer failing, and
hence, the wear member being lost. In an effort to increase the
life of the tooth assembly, the retainer is usually set very
tightly in the defined opening. Consequently, in the event of the
retainer being a pin, the retainer must be forcibly driven into and
out of an opening. The retainer is typically installed through the
wear member and adaptor by repeated blows with a heavy
sledgehammer. As can be appreciated, this is an onerous and
time-consuming task, especially in the larger sized teeth.
[0004] The construction of prior tip assemblies enabled forces
acting on the wear member to be exerted on the retainer, causing
such retainer to break or loosen during operation. One of the
reasons for this is that the primary load transmitting surface,
employed on the wear member of prior designs and the mating load
carrying surface on the adapter of such tip assembly, is disposed
at too great of an angle or distance relative to the forces acting
on the wear member. As a consequence, a component of the forces
acting in an upward or downward direction is created. This upward
or downward component force tends to rotate the wear member about
and pull the wear member away from the adapter.
[0005] One example of an excavating tooth assembly that strives to
simplify the installation procedure is disclosed in U.S. patent
Publication 2002/0000053 A1 issued Jan. 3, 2002 to Dwight L. Adamic
et al. In this publication a frustoconical opening is positioned in
one side of a wear member. An internally threaded retainer,
preferably made of polycarbonate, is positioned in the
frustoconical opening in a non-rotatable fashion. The wear member
is positioned over an adapter that is attachable to a cutting edge
of an implement, such as a bucket. The adapter has a retainer
receiving opening that generally aligns with the opening in the
wear member. With the wear member positioned over the adapter an
externally threaded fastener, having a tapered end portion, is
threaded into the retainer. The fastener is tightened into the
retainer until the tapered end portion of the fastener makes
contact with the anterior surface of the retainer receiving
opening. However, this publication does not address any features of
the interface between the adapter and wear member that helps to
distribute the heavy loads that the assembly is subjected to during
use.
[0006] The present invention is directed to overcoming one or more
of the problems as set forth above.
SUMMARY OF THE INVENTION
[0007] In one aspect of the present invention a tip assembly is
provided.
[0008] The tip assembly includes an adapter configured to be
secured to a cutting edge of an implement. The adapter has a
forward end portion, a pair of elevationally spaced surfaces, and a
pair of transversely spaced sides. At least one of the transversely
spaced sides has a retainer pocket and a guide arrangement
positioned thereon. The tip assembly also includes a wear member.
The wear member has a body with an exterior ground-engaging
surface, a mounting end, at least one ear extending from said
mounting end and an adapter receiving cavity opening through said
mounting end. The cavity is configured to receive the adapter. The
ear is configured to be received in close abutting relationship
with the guide arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a diagrammatic perspective view of a tip assembly
embodying the present invention;
[0010] FIG. 2 is an enlarged partial perspective view of the
adapter block of the tip assembly of FIG. 1;
[0011] FIG. 3 is a side view of the adapter illustrated in FIG.
2;
[0012] FIG. 4 is a top view of the adapter of FIG. 2, with a
portion shown in section;
[0013] FIG. 5 is a rear perspective view of the wear member from
the tip assembly illustrated in FIG. 1;
[0014] FIG. 6 is a side cross-sectional view of the wear member
taken generally along line 6-6 in FIG. 5;
[0015] FIG. 7 is a rear planar view of the tip;
[0016] FIG. 8 is an exploded perspective view of the retainer of
the present invention;
[0017] FIG. 9 is a cross-sectional view of the barrel member of the
retainer shown in FIG. 8;
[0018] FIG. 10 is a side elevational view of the fastener member of
the retainer shown in FIG. 8; and
[0019] FIG. 11 is a partial cross-sectional view of the tooth taken
along line 11-11 of FIG. 1.
DETAILED DESCRIPTION
[0020] Referring now to FIG. 1, there is illustrated a mechanically
attached tip assembly 10 for use on an implement 12 such as a
bucket of a backhoe loader, excavator, or wheel loader (not shown).
While only one such tip assembly 10 is shown, those skilled in the
art will understand that generally a plurality of such tip
assemblies 10 are distributed along the cutting edge 14 of such an
implement 12. Each tip assembly 10 includes an adapter 16 and a
replaceable wear member 18, which is selectively retained on the
adapter 16 by a retainer 20, as best seen in FIGS. 8-11.
[0021] As depicted in FIGS. 1-4, the adapter 16 has a pair of
bifurcated straps 22 that fit in mating contact with the cutting
edge 14 of the implement 12. The adapter 16 is secured to the
cutting edge 14 of the implement 12 by welding along a chamfered
edge surface 24 on both sides of the straps 22. However, the
adapter 16 may also be a half strap or a bolt on type design
without departing from the functionality of the present design.
While not shown, it should be understood that the straps 22 of the
adapter 16 might be configured so as to position the adapter 16 at
an angle with respect to a central axis 26, either upward or
downward for different implement 12 applications. For example, if
the tip assembly 10 is used on a wheel loader bucket, the tip
assembly 10 may be positioned so that the bottom of the wear member
18 is parallel with the bottom of the wheel loader bucket. However,
if the tip assembly 10 is used on an excavator bucket the tip
assembly 10 may be angled with respect to the bottom of the
bucket.
[0022] The adapter 16 has a forward end portion 30 positioned
distally from the implement 12, a pair of elevationally spaced
surfaces 34,36 and a pair of transversely spaced sides 38,40. The
forward end portion 30 defines a blunt end 42 and a generally
rectangular body 44 that extends outward a predetermined distance
from the elevationally spaced surfaces 34,36 and the transversely
spaced sides 38,40. For purposes hereinafter described, the
elevationally spaced surfaces 34,36 are non-parallel surfaces that
extend at an angle with respect to the central axis 26 and are
divergent from the forward end portion 30. In this manner, the
elevationally spaced surfaces 34,36 form an included angle a of
about 30 degrees. In one embodiment, at least one of the
transversely spaced sides 38 of the adapter 16 has a retainer
pocket 48 formed therein having an inward or bottom surface 50
lying along a first plane 52. Such one transverse side 38 lies
along a second plane 54 that is slightly angled with respect to the
first plane 52. Preferably, the second plane 54 of transverse side
38 is positioned at about a one to two degree angle with respect to
first plane 52 so as to facilitate removal from a mold or die
during manufacturing.
[0023] Interposed the straps 22 and the forward end portion 30 is a
guide arrangement 56. The guide arrangement 56 includes a raised
rib 58 and an upper and a lower raised shoulder 60. Raised rib 58
is interposed the upper and lower raised shoulders 60 and extends
along central axis 26 rearward from the retainer pocket 48 towards
the straps 22. The forward end of raised rib 58 forms part of a
wall surface extension 62 of the retainer pocket 48. Raised rib 58
projects outward from the one transverse side 38 a predetermined
distance and forms a pair of spaced sides 64, and an outer raised
surface 66. The outer surface 66 lays along a third plane 68 that
is spaced outward from and parallel to second plane 54, as best
seen in FIG. 4. Upper and lower raised shoulders 60 both include an
inner surface 68 that is positioned inward towards and parallel to
central axis 26. An outer edge 70 of the upper and lower raised
shoulders 60 lie along a fourth plane 71 that is spaced outward
from and parallel to third plane 68.
[0024] The retainer pocket 48 defines a bore 72 that extends inward
from the second plane 54 adjacent the raised rib 58 and terminates
at inner surface 50. The bore 68 has a predetermined diameter so
that it extends radially outward at a distance greater than the
predetermined width of the raised rib 58. Located in the bore 68,
the retainer pocket 48 may have an alignment configuration 74
represented as being a raised surface or key member. It should be
recognized that the alignment configuration 74 is not required for
function of the disclosed arrangement, and may consist of a groove,
flat surface or any of a number of other configurations, the use of
which will be described in more detail below. In addition, the
opposite transverse side 40 of the mounting block 16 may be
configured as described above for the one transverse side 38.
[0025] As best depicted in FIGS. 5-7, the replaceable wear member
18 has a body 76 with an exterior ground-engaging surface 78, a
mounting end 80, a pair of ears 82,83 and an adapter-receiving
cavity 84 opening through the mounting end 80. The exterior
ground-engaging surface 78 has a generally wedge shaped profile so
as to better penetrate the materials it engages during a digging
operation.
[0026] The adapter-receiving cavity 84 of the wear member 18 is
configured to receive the adapter 16 and has a forward surface 88
disposed for axial load transferring abutting engagement with the
blunt end 42 of the adapter 16. The adapter-receiving cavity 84
also has sidewalls defining a pair of transversely spaced side
surfaces 90,92 and a pair of elevationally spaced surfaces 94,96.
The elevationally spaced surfaces 94,96 are configured to be in
close abutting relationship to a respective one of the
elevationally spaced surfaces 34,36 of the adapter 16 for
transferring vertical load forces generated during a digging
operation.
[0027] At least one of the pair of ears 82 of the wear member 18
includes a groove 98 positioned in ear 82 that extends from an end
99 along the axial length thereof towards the adapter-receiving
cavity 84. The groove 98 defines a pair of opposed surfaces 100,102
and an inner surface 104. The raised rib 58 on the adapter 16 is
adapted to be received by and positionable in relationship with the
groove 98. Specifically, the spaced sides 64 and the outer surface
66, of the raised rib 58, are positioned in close abutting
relationship to the opposed surfaces 100,102 and the inner surface
104 respectively of the groove 98 when the wear member 18 is
mounted on the adapter 16. Upon such mounting, an upper and a lower
surface 106 of the one ear 82 is positioned in close relationship
to the inner surface 68 of the upper and lower raised shoulders 60.
The raised rib 58 and the groove 98, and the upper and lower
surfaces 106 of the ear 82 and the inner surfaces 68 of the upper
and lower raised shoulders 60 are also configured to assist in the
transferring of vertical load forces generated during a digging
operation.
[0028] A through-hole 108 extends from the exterior ground engaging
surface 78 through to the adapter receiving cavity 84 and is
positioned at the end of the groove 98 centrally positioned in the
body 76 of the wear member 18. The through-hole 108 is alignable
with the retainer pocket 48 in the adapter 16 and is generally
coaxial with the bore 70, the purpose of which will become
subsequently apparent. Preferably, the through-hole 108 is
configured to be a slot so that as the adapter 16 wears, and
replacement wear members 18 are mounted thereon, the through-hole
108 will align with the retainer pocket 48 thus providing extended
life of the adapter 16. The ears 82,83 also aid in transferring
side loads between the adapter 16 and the wear member 18. In
addition, the opposite other ear 83 may be configured as described
above for the one ear 82.
[0029] As best shown in FIGS. 8-10, the retainer 20 is used for
detachable retaining the wear member 18 to the adapter 16. In one
embodiment, retainer 20 includes a fastening member 110 and a
barrel member 112. The fastening member 110 is provided with a
threaded stud portion 114 and a generally cylindrical head portion
116. The cylindrical head portion 116 includes a tool socket 118 in
the end thereof. Disposed between the threaded stud portion 114 and
the cylindrical head portion 118 is a tapered portion 120 that
blendingly connects the threaded stud portion 114 to the
cylindrical head portion 118.
[0030] The barrel member 112 is generally cylindrical in shape and
of a predetermined diameter. The barrel member 112 is disposed
along a central axis 122 and has a threaded bore 124 in one end
thereof that is adapted to be threadably engaged by the threaded
stud portion 114 of the fastening member 110. Positioned in the
other end of the barrel member 112 is a tapered socket 126 that is
adapted to be engaged by the tapered portion 120 of the fastening
member 110. A first end 130 of the barrel member 112, adjacent the
threaded bore 124, includes a chamfer 132 that provides a lead for
insertion into the retainer pocket 48. A second end 136, adjacent
the tapered socket 126, includes a pair of spaced surfaces 140,142.
A mating configuration 144 may be coaxially positioned on the
generally cylindrical outer surface of the barrel member 112 shown
as being a groove. It should be recognized that the mating
configuration 144 could be a raised surface or a flat on the
generally cylindrical surface of the barrel member 112 or any of a
number of other configurations that will mate with the alignment
configuration 74 in the bore 72 of the retainer pocket 48.
[0031] The barrel member 112 is adapted for receipt into the
retainer pocket 48 of the adapter 16 and to engage one of the wear
member 18 or the adapter 16 to prevent the rotation of the barrel
member 110 upon the application of a torquing or tightening force
thereto by means of a suitable tool which is placed in the tool
socket 126 of the fastening member 110. If the alignment
configuration 74 and the mating configuration 144 are used, the
alignment configuration 74 in the bore 72 of the retainer pocket 48
and the mating configuration 144 of the barrel member 112 allow
only a specific orientation so that the replaceable wear member 18
is able to be placed on the adapter 16. Otherwise, the pair of
spaced surfaces 140,142 of the barrel member 112 need to be aligned
with the spaced side surfaces 64 of the raised rib 58. In this
manner, the opposed surfaces 100, 102 of the groove 98 in the one
ear 82 can be positioned adjacent the spaced surfaces 140,142 and
the spaced side surfaces 64 of the barrel member 112 and the raised
rib 58, respectively. Once the wear member 18 is mounted, the
fastener member 110 is inserted into the through-hole 108 of the
wear member 18 and screwed into the threaded bore 124 of the barrel
member 110. The predetermined diameter of the cylindrical surface
116 of the fastener member 110 is selected for close receipt of the
fastener member 110 in the through-hole 108.
[0032] Once assembled, the wear member 18 is retained on the
adapter 16 through engagement of the barrel member 112 of the
retainer 20 by the fastening member 110 through the through-hole
108 in the wear member 18. While not essential, two retainers 20
may be employed in retaining the wear member 18, on either side of
tooth assembly 10.
[0033] Industrial Applicability
[0034] The benefits mentioned above are accomplished by various
features of the present tip assembly 10. In particular, the
elevationally spaced surfaces 34,36, the transversely spaced sides
38,40 and the guide arrangement 56 of the adapter 16 and the
respectively corresponding elevationally spaced surfaces 94,96, the
spaced inner sides 90,92 and the ears 82,83 of the wear member 18
provide the primary load transferring surfaces for transferring
forces therebetween. Such configurations are oriented substantially
perpendicular to vertical and side forces acting on the wear member
18. As a consequence, minimal components of force are created,
thereby reducing the tendency of the wear member 18 to pivot
relative to the adapter 16. Also, the mounting end 84 of the wear
member 18 is constructed so as not to contact the adapter 16 when
the wear member 18 is mounted thereon. This prevents the mounting
end 80 of the wear member 18 from acting as a fulcrum that is
located at a distance from the retainer 20. Thus, any resulting
pivotal movement of the wear member 18 at the retainer 20 is
reduced as compared to prior tip assemblies.
[0035] Retainer breakage is also reduced by the fact that the loads
exerted on the retainer 20 are exerted on the generally cylindrical
head portion 116 of the fastening member 110 through the
through-hole 108 in the wear member 18 on one side and exerted on
the barrel member 112 through the concave surface 62 of the raised
rib 58 of the adapter 16 on the other side.
[0036] The tip assembly 10 of the present invention has a
construction especially adapted for transferring forces exerted on
the wear member 18 into the adapter 16 in a manner so as to isolate
the transmission of such forces from the retainer 20, thus reducing
the breakage of such retainer 20. The construction of the present
retainer 20 and its containment in the wear member 18 maximizes its
load carrying capabilities, while at the same time relieving such
retainer 20 from experiencing the high loads exerted on the
retainers of prior tip designs. Additionally, the adapter 16 and
the wear member 18 are constructed in such a manner as the wear
member 18 to move backwards on the adapter 16 as the adapter wears
during use.
* * * * *