U.S. patent application number 12/091817 was filed with the patent office on 2008-10-23 for tip assembly for earth moving machinery.
This patent application is currently assigned to ESTI S.R.I.. Invention is credited to Giovanni Esti.
Application Number | 20080256832 12/091817 |
Document ID | / |
Family ID | 36681795 |
Filed Date | 2008-10-23 |
United States Patent
Application |
20080256832 |
Kind Code |
A1 |
Esti; Giovanni |
October 23, 2008 |
Tip Assembly for Earth Moving Machinery
Abstract
The invention relates to a tip assembly for earth moving
machinery, comprising a tip (11) having a pocket (12) open at the
back, said tip exhibiting a hole (16) for seating a locking key, an
adapter (41) having a nose (42) that geometrically couples with
said pocket (12), said nose being crossed by a seat (43) for
seating the locking key, and a locking key (61) inserted in said
hole in the tip and in said seat in the adapter for locking the tip
to the adapter. At least one surface of the nose exhibits a lowered
or recessed zone obtained around the seat for the locking key. At
least the wall of the pocket facing said surface of the nose
internally exhibits a relief complementary to said lowered or
recessed zone. In this way, the coupling between the tip and the
adapter is made stronger by the interaction between at least two
respective facing surfaces.
Inventors: |
Esti; Giovanni; (Brescia,
IT) |
Correspondence
Address: |
KILYK & BOWERSOX, P.L.L.C.
400 HOLIDAY COURT, SUITE 102
WARRENTON
VA
20186
US
|
Assignee: |
ESTI S.R.I.
Idro
BS
|
Family ID: |
36681795 |
Appl. No.: |
12/091817 |
Filed: |
November 25, 2005 |
PCT Filed: |
November 25, 2005 |
PCT NO: |
PCT/IT2005/000692 |
371 Date: |
April 28, 2008 |
Current U.S.
Class: |
37/456 ; 37/452;
37/455 |
Current CPC
Class: |
E02F 9/2825 20130101;
E02F 9/2841 20130101 |
Class at
Publication: |
37/456 ; 37/452;
37/455 |
International
Class: |
E02F 9/28 20060101
E02F009/28 |
Claims
1-40. (canceled)
41. A tip assembly for earth moving machinery, having a
longitudinal axis (X) that extends at the front and at the back and
comprising: a tip defining a pocket open at the back defining a
female portion, said tip having a hole for seating a locking key
obtained in a pair of opposed walls defining said pocket; an
adapter having a nose defining a male portion that geometrically
couples with said pocket, said nose being crossed by a seat of the
locking key, said seat extending between two opposed surfaces of
said nose and being aligned with said hole in the tip; and a
locking key inserted in said hole in the tip and in said seat in
the adapter for locking the tip to the adapter, wherein at least
one of said opposed surfaces of the nose has a lowered or recessed
zone obtained around the seat for the locking key, and wherein at
least the wall of the pocket facing said surface of the nose
internally has a relief complementary to said lowered or recessed
zone and in the form of a thickening progressively increasing
towards the pocket opening, wherein said hole in the pocket walls
and said seat in the nose have respective plane back surfaces
aligned each other, and wherein said locking key has a plane back
surface resting at the same time on said back surfaces of the hole
and of the seat.
42. A tip assembly according to claim 41, wherein the nose and the
pocket comprise respective opposed surfaces and walls inclined
relative to said longitudinal axis (X) and converging at the front,
the seat in the nose and the hole in the pocket being extended
between said inclined surfaces and walls.
43. A tip assembly according to claim 41, wherein the hole in the
pocket and the seat in the nose extend around a transversal axis
(Y) perpendicular to said longitudinal axis (X).
44. A tip assembly according to claim 43, wherein said lowered or
recessed zone is defined by a plane portion perpendicular to said
transversal axis (Y).
45. A tip assembly according to claim 42, wherein said inclined
surfaces and walls of the nose and pocket, respectively, are top
and bottom surfaces and walls of the nose and of the pocket.
46. A tip assembly according to claim 45, wherein nose and pocket
comprise respective opposed side surfaces and walls substantially
vertical.
47. A tip assembly according to claim 46, wherein each of said side
surfaces of the nose comprises, for the full extension thereof, a
kerb or guide tongue parallel to the longitudinal axis (X) and
wherein each of said side walls of the pocket internally comprises
s a guide groove suitable for receiving said kerb or guide tongue
of the nose.
48. A tip assembly according to claim 41, wherein said locking key
comprises a front surface engaging the adapter.
49. A tip assembly according to claim 48, wherein said locking key
comprises a back portion defining said back surface, a front
portion defining said front surface and an intermediate portion
made of elastic material.
50. A tip assembly according to claim 49, wherein said intermediate
portion is suitable for allowing an introduction by compression of
the locking key in the adapter seat.
51. A tip assembly according to claim 50, wherein the intermediate
portion of the locking key is made of elastomeric material.
52. A tip assembly according to claim 51, wherein said elastomeric
material is rubber.
53. A tip assembly according to claim 41, wherein the hole in the
pocket and the seat in the nose comprise respective front surfaces
that extend parallel to the transversal axis (Y), the front surface
of the seat being rear relative to the front surface of the hole so
as to define a step at the top and an undercut at the bottom.
54. A tip assembly according to claim 53, wherein the locking key
comprises a central portion seated by compression in the adapter
seat and end portion respectively interacting with said step and
said undercut so as to axially constrain the locking key.
55. A tip assembly according to claim 54, wherein said end portions
protrude at the front beyond the central portion so as to define
respective steps therewith.
56. A tip assembly according to claim 55, wherein the pocket walls
with the hole for the key have, at the level of said hole, a
thickness at least equal to the height extension of said end
portions of the locking key.
57. A tip assembly according to claim 56, wherein at least the wall
in the top wall of the pocket defines, with the step formed by the
front surface of the seat in the adapter, a seat for a guided
pre-introduction of the locking key in the hole in the pocket and
in the seat in the adapter.
58. A tip assembly according to claim 41, wherein the tip and the
adapter comprise coupling portions shaped to penetrate each other
when said tip and adapter are assembled.
59. A tip assembly according to claim 58, wherein the junction line
of the tip to the adapter when assembled is a broken line.
60. A tip assembly according to claim 41, wherein the adapter nose
extends from a body of connection to the earth moving machinery
bucket, said connecting body comprising at the front a peripheral
edge substantially plane that surrounds the nose and that defines a
shoulder or support stop for the tip.
61. A tip assembly according to claim 60, wherein at least one side
of said peripheral edge has a breakage wherein there is introduced
a respective complementary tooth extending from at least one of the
walls delimiting the pocket of the tip.
62. A tip assembly according to claim 41, wherein the pocket in the
tip ends at the front with a plane bottom defining a front stop for
the nose.
63. A tip assembly according to claim 62, wherein the nose
comprises a substantially plane front end resting against the plane
bottom of the pocket.
64. A tip assembly according to claim 62, wherein said plane bottom
of the pocket is surrounded by a groove or peripheral slot.
65. A locking key for a tip assembly of a bucket of an earth moving
machinery, having an elongated body that extends along a main axis
(Y), comprising two side portions extending parallel to said main
axis from one end to the other of the key and a central portion of
elastic material arranged between said side portions, wherein one
of said side portions has s a plane outer surface, wherein one of
said side portions comprises, relative to said main axis, a central
portion from which two end portions extend, transversally
protruding from said central portion, at least in the opposed
direction relative to the other side portion, so as to define with
said central portion respective steps or undercuts.
66. A locking key according to claim 65, wherein said side portion
has a rectangular cross section.
67. A locking key according to claim 65, wherein the other of said
side portions has a substantially semicircular cross section.
68. A locking key according to claim 67, wherein said protruding
side portions are obtained in the side portion with semicircular
section.
69. A tip for a bucket of an earth moving machinery, having a
pocket open at a back end and defined by a top wall, a bottom wall
and side walls, wherein said top and bottom walls are inclined and
converging towards a front end of said tip, and wherein said top
and bottom walls are crossed by a hole suitable for receiving a key
for locking the tip to a adapter, wherein from each of said top and
bottom walls, around said hole, there extends a protruding portion
towards the interior of the pocket suitable for geometrically
coupling with a corresponding lowered zone obtained in the adapter,
wherein that at the side opposite the opening, said pocket
comprises a plane bottom surrounded by a groove or peripheral
slot.
70. A tip according to claim 69, wherein said protruding portion is
obtained from a thickening of the respective wall about the hole
for the locking key, said thickening progressively increasing
towards the pocket opening so as to define a plane perpendicular to
the hole axis.
71. A tip according to claim 69, wherein a guide groove is obtained
in the inner surface of each of said side walls.
72. A tip according to claim 69, wherein a toot extends from at
least one of the sides delimiting the pocket opening in
continuation from the respective wall.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a tip assembly for earth
moving machinery, such as excavators.
BACKGROUND OF THE INVENTION
[0002] In accordance with the preamble of claim 1, tip assemblies
for earth moving machinery are known, comprising a tip, an adapter
and a key for locking the tip to the adapter.
[0003] The tip exhibits a pocket open at the back defining a femal
portion and a hole for seating the locking key obtained in a pair
of opposed walls defining said pocket.
[0004] The adapter exhibits a body shaped to be attached, for
example by welding or bolting, to the machine bucket and a nose
that extends from said body and that defines a male portion that
geometrically couples with the tip pocket. The nose is crossed by a
seat of the locking key, said seat extending between two opposed
surfaces of said nose and being aligned with the hole in the
tip.
[0005] The manufacture of the tip assembly into two separable
portions, tip and adapter, advantageously allows the replacement of
the tip only, when worn, while the adapter remains permanently
attached to the machine bucket. The system for lockingh the tip to
the adapter, obtained for example by the key, must therefore be
suitable for allowing an easy and quick replacement of the tip.
[0006] However, this need is in conflict with the need of making
the coupling between tip and adapter as tight as possible, due to
the considerable strains the tip is subject to.
[0007] In fact, in some known tip assemblies, in order to make the
tip replacement operation easy and quick, the due interference
between the locking key and the seat thereof is not provided, with
the result that with the extended use, the key could extract from
said seat, thus causing the separation of the two portions of the
tool.
[0008] In other known embodiments, special stopping devices, for
example of the elastic type, suitable for interacting with the nose
of the adapter, have been provided in the key itself in order to
tightly constrain the locking key into position. Besides making the
tip assembly structure more complex to manufacture and therefore
more expensive, such solutions have not completely solved the
problem of avoiding the disconnection of the tip from the adapter
in heavy operating conditions. In fact, all the efforts aimed at
this have basically addressed the coupling between the locking key,
the tip and the adapter, and therefore they have been restricted to
a limited area of the tip assembly.
[0009] Some strains the tip assembly is subject to while in use, in
fact, are such that if they are mainly opposed by the locking key
only, they could cause the breakage thereof and therefore the tip
disconnection from the adapter.
[0010] The need of combining the requirement of making the tip as
integral as possible with the adapter so as to effectively oppose
even the heaviest strains the tip assembly is subject to, and of
facilitating the tip replacement, for example through a convenient
and quick removal of the locking key, is therefore greatly
felt.
[0011] The object of the present invention therefore is to meet the
above need while solving the disadvantages of the tip assemblies of
the prior art.
[0012] Such object is achieved with a tip assembly according to the
following claim 1.
[0013] The features and advantages of the invention will appear
more clearly from the following description of some preferred
embodiments thereof, with reference to the annexed indicative and
non-limiting drawings, wherein:
[0014] FIG. 1 shows a perspective view of the tip assembly
according to the present invention;
[0015] FIG. 2 shows a vertical axial section of the tip
assembly;
[0016] FIG. 3 shows an enlarged axial section of the central and
front portion of the tip assembly;
[0017] FIG. 3a shows a section similar to the previous one but with
the locking key in a pre-introduction position;
[0018] FIG. 4 shows a perspective view of the tip only;
[0019] FIG. 5 shows an axial section of the tip;
[0020] FIG. 6 shows the tip viewed from the back end;
[0021] FIG. 7 shows a perspective top view of the adapter;
[0022] FIG. 8 shows a perspective bottom view of the adapter;
[0023] FIG. 9 shows a side view of the adapter;
[0024] FIG. 10 shows a perspective view of the locking key;
[0025] FIG. 11 shows an elevation view of the key;
[0026] FIG. 12 shows a plan view of the key in home position;
and
[0027] FIG. 13 shows a plan view of the key in use position.
[0028] With reference to the figures, the tip assembly according to
the present invention comprises a tip 11, an adapter 41 and a
locking key 61.
[0029] The tip assembly basically extends along a longitudinal axis
X relative to which it is possible to determine a back portion and
a front portion of the tip assembly. Axis X also coincides with the
assembly direction of the tip to the adapter.
[0030] Tip 11 is the actual earth moving tool while adapter 41 is
the element for attaching the tip assembly to the bucket of an
earth moving machinery, such as an excavator, in this case partly
represented by a blade 10. While tip 11 is replaced when worn,
adapter 41 remains normally attached to the bucket. The locking key
61 tightly secures tip 11 to adapter 41.
[0031] Tip 11 exhibits a front working portion 11' and a back
portion 11'' for coupling with adapter 41. The coupling between tip
11 and adapter 41 is of the male-female type, the back portion 11''
of the tip defining the female portion of the coupling. More in
detail, said back portion 11'' comprises a pocket 12 open at the
back.
[0032] Adapter 41 exhibits a front portion 42, hereinafter referred
to as nose, and a back portion 50, called adapter body. Nose 42 is
the male portion of the coupling with the tip and is shaped
complementary to pocket 12 for introducing therein and
geometrically coupling thereto.
[0033] Nose 42 extends from body 50, which exhibits a shape, such
as a V shape, for being attached, such as by welding of screwing,
to blade 10.
[0034] In accordance with a general embodiment, tip 11 exhibits a
hole 16 for seating the locking key 61 obtained in a pair of
opposed walls 13, 14 delimiting pocket 12. Correspondingly, nose 42
is crossed by a seat 43 for the locking key 61, said seat extending
between two opposed surfaces 47, 48 of said nose and being aligned
with hole 16 in tip 11.
[0035] According to the invention, at least one of said opposed
surfaces of nose 47, 48, preferably both, exhibits a lowered or
recessed zone 49 obtained around seat 43 for the locking key 61.
Correspondingly, each wall of pocket 12 facing each surface of the
nose exhibiting the lowered zone 49 internally exhibits a relief 18
complementary to said lowered or recessed zone 49. After the
introduction of nose 42 into pocket 12, relief 18 matches the
lowered zone 49, geometrically coupling therewith.
[0036] In accordance with a preferred embodiment, walls 13, 14 of
pocket 12 crossed by hole 16 and surfaces 47, 48 of nose 42 with
seat 43 are inclined relative to the longitudinal axis X and
converging at the front.
[0037] According to a preferred embodiment, hole 16 in the pocket
and seat 43 in the nose extend around a transversal axis Y
perpendicular to said longitudinal axis X. Advantageously, relative
to the tip assembly at home position shown in FIGS. 1 and 2, wall
13 and surface 47 face upwards, whereas wall 14 and surface 48 face
backwards. In other words, considering the longitudinal axis X
extending horizontally, the transversal axis Y is substantially
vertical. In the presence of multiple tip assemblies next to one
another at a short distance therefrom, this arrangement allows a
convenient application and removal of the key from the top, that
is, without the adjacent tip assemblies being a hindrance to such
operations.
[0038] Advantageously, said lowered or recessed zone 49 is defined
by a plane portion perpendicular to said transversal axis Y.
Correspondingly, said relief 18 emerging from each of the inclined
walls 13, 14 of pocket 12 is obtained by a thickening of said walls
about hole 16 for the locking key 61, said thickening progressively
increasing towards the pocket opening so as to define a plane
perpendicular to said transversal axis Y.
[0039] In accordance with an embodiment, nose 42 and pocket 12
exhibit respective opposed side surfaces and walls 54, 15
substantially vertical. Advantageously, each of said side surfaces
54 of nose 12 exhibits, for the full extension thereof, a kerb or
guide tongue 55 parallel to the longitudinal axis X.
Correspondingly, each of said side walls 15 of pocket 12 internally
exhibits a guide groove 22 suitable for receiving said kerb or
guide tongue 55 of the nose.
[0040] In accordance with a further aspect of the invention, pocket
12 ends at the front with a plane bottom 20 defining a front stop
for nose 42. The latter exhibits a substantially plane front end 53
resting against said plane bottom 20 of the pocket. In other words,
pocket 12 and nose 42 take up the shape of a parallelepiped with
trapezoidal section of a truncated pyramid.
[0041] Advantageously, said plane bottom 20 of the pocket is
surrounded by a peripheral slot or groove 21 suitable for receiving
any scrap or residues, for example due to pressing, casting or
coating of tip 11. Said groove 21 ensures that adapter 42 always
abuts against the stop plane 20, also in the presence of scrap,
residues or dirt inside pocket 12. Consequently, hole 16 is always
aligned with seat 43. Hole 16 and seat 43 can thus be made in a
very accurate manner, without the need of providing for clearance
for compensating any misalignment, clearance which would negatively
affect the efficiency of locking of the tip to the adapter.
[0042] According to another aspect of the invention, besides the
lowered zones 49 of the nose and corresponding reliefs 18 of the
pocket, tip 11 and adapter 41 exhibit further coupling portions
shaped to penetrate each other when said tip and adapter are
assembled. In particular, such reciprocal penetration is
advantageously realised at the level of the surfaces of abutment of
the tip on the adapter along the longitudinal axis X.
[0043] For example, body 50 of the adapter exhibits at the front a
peripheral edge 51 substantially plane that surrounds nose 42 and
that defines a shoulder or support stop for tip 11. Advantageously,
at least one side of said peripheral edge, preferably two opposed
sides, exhibits a breakage 52 wherein there is inserted a
respective complementary tooth 19 which extends in continuation
from at least one, preferably two opposed, of the walls delimiting
pocket 12. In other words, the junction line of the tip to the
adapter is a broken line.
[0044] According to a further aspect of the invention, hole 16 in
pocket 12 and seat 43 in nose 42 exhibit respective back surfaces
16a, 43a substantially plane. Similarly, the locking key 61
exhibits a back surface substantially plane 62 resting on said back
surfaces of the hole and of the seat. In other words, the coupling
between the back surface 62 of the locking key, tip 11 and adapter
42 is a coupling between plane surfaces.
[0045] More in detail, the locking key 61 exhibits a back portion
64 defining said back surface 62, a front portion 65 defining a
front surface 63 and an intermediate portion 66 made of elastic
material. Said intermediate portion 66 is suitable for allowing an
introduction by compression of the locking key 61 in the adapter
seat. In other words, the transversal section of seat 43 in nose 42
is lower than the transversal section of the central portion 67 of
key 61 intended for seating into said seat. Only by a compression
of the intermediate portion 66 that allows moving the front 65 and
back 64 portions close to each other, key 61 is introduced into
seat 43.
[0046] Advantageously, the intermediate portion 66 of the locking
key 61 is made of elastomeric material, such as rubber. The two
front and back portions of the key can for example be made of
steel.
[0047] In one embodiment, hole 16 and seat 43 exhibit respective
front surfaces 17, 44 that extend parallel to the transversal axis
Y. Advantageously, the front surface 44 of the seat is rear
relative to the front surface 17 of hole 16 so as to define a step
45 (at the top) and an undercut 46 (at the bottom) therewith.
[0048] Relative to the transversal axis Y, which substantially
coincides with the main axis along which key 61 extends, the latter
exhibits end portions 68 respectively interacting with said step 45
and with said undercut 46 so as to axially constrain key 61 into
seat 43. Advantageously, said end portions 68 protrude at the front
beyond the central portion 67 so as to define respective steps 69
therewith.
[0049] According to a preferred embodiment, the back portion 64 of
the locking key 61 exhibits a rectangular cross section, whereas
the front portion 65 exhibits a substantially semicircular cross
section. Moreover, each end portion 68 ends with a chamfer 70
acting as seat for an easy introduction of key 61 into seat 43. It
should be noted, moreover, that the elastic intermediate portion 66
exhibits a longitudinal extension, that is, along axis Y, smaller
than the adjacent front 65 and back 64 portions, so as to be
protected thereby when the key is pushed into seat 43 or removed
from seat 43 with a tool acting on the end portions 68.
[0050] According to an advantageous embodiment, walls 13, 14 of the
pocket crossed by hole 16 for key 61 exhibit, at the level of said
hole 16, a thickness at least equal to the height extension of said
end portions 68 of the locking key 61. Moreover, at least at the
top wall 13, said hole 16 defines, with the underlying step 45, a
seat for a guided pre-introduction of the locking key 61 in hole 16
of the pocket and in seat 43 in the adapter. In other words, the
section of hole 16 is equal or slightly greater than the section of
the end portions 68 of key 61, so that an end of the key may be
inserted in a guided manner in hole 16 and may remain autonomously
resting thereon, that is, without the aid of an operator, as shown
in FIG. 3a. Such guided pre-introduction of the key enables the
operator to push the key into seat 43 in an easy manner (the key
being already perfectly aligned with the seat) and safely (it is
not necessary to use the hands to hold the key into position), for
example using a hammer.
[0051] The advantages of the structure of the tip assembly
described above are several.
[0052] In the first place, providing for lowered zones, or recessed
in the nose, and for corresponding reliefs in the pocket, besides
the presence of the side guide kerbs, allows involving all the
sides of the nose and of the pocket in the coupling, with a
considerable increase of the tearing strength. In particular, the
coupling between the reliefs and the lowered zones involves the
nose at the seat for the locking key, that is, close to the
connection to body 50, where its thickness is larger. Even in the
event of a large reduction of the side coupling, for example due to
the wear of the guide kerbs, the connection between the reliefs and
the lowered zones ensures a constant and high tear strength due to
the mechanical strains the tip assembly is subject to.
[0053] The effect of reciprocal penetration between the tip and the
adapter and therefore a stronger coupling is further increased by
the connection between the breakages in the adapter body and the
complementary teeth that extend from the tip.
[0054] The presence of the lowered zones and of the reliefs in the
pocket has the further effect of increasing the rest surface of the
locking key to the back surface 16a of hole 16. Such increase of
rest surface allows the corresponding increase of the resistance to
the extraction of the tip from the adapter to prevent possible
breakage due to an excessive pressure on the tip portion in contact
with the key.
[0055] The presence of the plane contact surfaces between the
locking key, the hole and the seat in the nose allows both having a
wide rest surface of the key to the tip and to the adapter, to the
advantage of the locking efficacy, both preventing any rotation of
the key due, for example, to the vibrations it is subject to. Such
undesired rotations could, in fact, cause a progressive extraction
of the key from the seat thereof due to the presence of a
compressible portion in the key.
[0056] Moreover, the key thus configured allows a single position
of introduction in the hole and in the seat and thus an always
correct snapping of the front step of the key in the undercut of
the adapter.
[0057] Moreover, it should be noted that the locking key is sized
so that the elastic intermediate portion compresses not only during
the introduction in the seat thereof, but it remains compressed
also after the introduction. Such compression, along with the
presence of the marked front steps, allows avoiding any risk of
accidental extraction of the key, for example due to the impact
with items or debris while the machinery is working.
[0058] As already mentioned above, the locking key and the hole in
the pocket are sized to allow a resting of the key into said hole
through an end portion thereof, already in aligned position with
the seat in the nose and without the need of being manually
supported.
[0059] Such easiness of assembly of the tip assembly is also due to
the presence of the abutment plane on the bottom of the pocket of
the tip and of the groove surrounding it. In fact, as already
explained above, said plane and said peripheral groove always
ensure the same positioning between the tip and the adapter, and
therefore a constant and perfect alignment between the hole in the
pocket and the seat in the nose.
[0060] Finally, it should be noted that the snap-wise coupling
between tip and adapter also at the level of the outer contact
surfaces imparts a very compact and smooth design to the tip
assembly, as if the two elements were a single body. This also
allows preventing any earth or other work materials from meeting
any hindrances while loading and emptying the bucket.
[0061] It is evident that a man skilled in the art may make several
changes and adjustments to the tip assembly according to the
present invention in order to meet specific and incidental needs,
all falling within the scope of protection of the invention as
defined in the following claims.
* * * * *