U.S. patent application number 15/271647 was filed with the patent office on 2018-03-22 for drawbar assembly for motor grader.
This patent application is currently assigned to Caterpillar Inc.. The applicant listed for this patent is Caterpillar Inc.. Invention is credited to Nathaniel K. Harshman, Sean M. Hayes, Lingfei Zhang.
Application Number | 20180080194 15/271647 |
Document ID | / |
Family ID | 61618378 |
Filed Date | 2018-03-22 |
United States Patent
Application |
20180080194 |
Kind Code |
A1 |
Hayes; Sean M. ; et
al. |
March 22, 2018 |
DRAWBAR ASSEMBLY FOR MOTOR GRADER
Abstract
A drawbar assembly for a motor grader is provided. The drawbar
assembly includes a yoke plate, a backbar, a drawbar tube, and a
sleeve. The yoke plate includes a first surface and a second
surface. The backbar is attached to the first surface of the yoke
plate. The backbar includes a tube facing surface. The drawbar tube
includes a first end and a second end. The drawbar tube is attached
to the first surface of the yoke plate, defining a clearance
between the first end of the drawbar tube and the tube facing
surface of the backbar. The sleeve encloses at least a portion of
the drawbar tube. The sleeve includes a backbar attachment portion
and a yoke attachment portion. The backbar attachment portion is
attached to the tube facing surface of the backbar and the yoke
attachment portion is attached to the first surface of the yoke
plate.
Inventors: |
Hayes; Sean M.; (Decatur,
IL) ; Harshman; Nathaniel K.; (Sullivan, IL) ;
Zhang; Lingfei; (Chicago, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Caterpillar Inc. |
Peoria |
IL |
US |
|
|
Assignee: |
Caterpillar Inc.
Peoria
IL
|
Family ID: |
61618378 |
Appl. No.: |
15/271647 |
Filed: |
September 21, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E01C 19/187 20130101;
E02F 3/7636 20130101 |
International
Class: |
E02F 3/76 20060101
E02F003/76; E01C 19/42 20060101 E01C019/42; E01C 19/48 20060101
E01C019/48; E01C 19/26 20060101 E01C019/26 |
Claims
1. A drawbar assembly for a motor grader, the drawbar assembly
comprising: a yoke plate including a first surface and a second
surface; a backbar attached to the first surface of the yoke plate,
the backbar including a tube facing surface; a drawbar tube
including a first end and a second end, wherein the drawbar tube is
attached to the first surface of the yoke plate, and wherein a
clearance is defined between the second end of the drawbar tube and
the tube facing surface of the backbar; and a sleeve adapted to
enclose at least a portion of the drawbar tube, the sleeve
including a backbar attachment portion and a yoke attachment
portion, wherein the backbar attachment portion is attached to the
tube facing surface of the backbar and the yoke attachment portion
is attached to the first surface of the yoke plate.
Description
TECHNICAL FIELD
[0001] The present disclosure generally relates to a drawbar
assembly for a motor grader.
BACKGROUND
[0002] Machines, such as motor graders, are commonly used in earth
levelling applications, such as road maintenance and surface
contouring. A motor grader generally employs a drawbar assembly
installed on a main frame of the motor grader. The drawbar assembly
supports a blade, which performs earth levelling during normal
operation of the motor grader. Typically, the drawbar assembly
includes a yoke plate, a backbar, and a pair of drawbar tubes. The
backbar is attached to the yoke plate and extends vertically from
the yoke plate. Each of the drawbar tubes is fixedly attached to
the yoke plate. Each of the drawbar tubes includes a first end and
a second end. The first end of each of the drawbar tubes is fixedly
attached to the main frame. The second end of each of the drawbar
tubes is fixedly attached to the backbar.
[0003] Conventionally, the motor grader has an increased weight for
various load bearing requirements of the motor grader. Due to the
increased weight of the motor grader, various components of the
drawbar assembly may undergo an increased amount of stress.
Moreover, as each of the drawbar tubes is relatively thinner than
the backbar, an attachment between each of the drawbar tubes and
the backbar may primarily experience the increased amount of
stress.
[0004] U.S. Patent Application Number 2015/0008296 (hereinafter
referred as the '296 reference) describes a drawbar assembly
including a backbar, a pair of drawbar tubes, and a number of
cylinder connection devices. In the '296 reference, one end of each
of the drawbar tubes is fixedly attached to the backbar. An
attachment between each of the first drawbar tube, the second
drawbar tube and the backbar undergoes the increased amount of
stress.
[0005] In these machines, increased stress may be experienced by
the drawbar assembly, leading to a reduced work life of the drawbar
assembly. This may also lead to an increased downtime and operating
cost of the motor grader, which in turn may reduce overall
productivity of the motor grader. Hence, there is a need for an
improved design for the drawbar assembly.
SUMMARY OF THE DISCLOSURE
[0006] Various aspects of the present disclosure describe a drawbar
assembly for a motor grader. The drawbar assembly includes a yoke
plate, a backbar, a drawbar tube, and a sleeve. The yoke plate
includes a first surface and a second surface. The backbar is
attached to the first surface of the yoke plate. The backbar
includes a tube facing surface. The drawbar tube includes a first
end and a second end. The drawbar tube is attached to the first
surface of the yoke plate, defining a clearance between the second
end of the drawbar tube and the tube facing surface of the backbar.
The sleeve encloses a portion of the drawbar tube. The sleeve
includes a backbar attachment portion and a yoke attachment
portion. The backbar attachment portion is attached to the tube
facing surface of the backbar and the yoke attachment portion is
attached to the first surface of the yoke plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a side view of a motor grader, in accordance with
the concepts of the present disclosure;
[0008] FIG. 2 is a perspective view of a drawbar assembly of the
motor grader of FIG. 1, in accordance with the concepts of the
present disclosure;
[0009] FIG. 3 is a perspective view of a first sleeve of the
drawbar assembly, in accordance with the concepts of the present
disclosure; and
[0010] FIG. 4 is a perspective view of an alternate embodiment of
the first sleeve of the drawbar assembly, in accordance with the
concepts of the present disclosure.
DETAILED DESCRIPTION
[0011] Referring to FIG. 1, a side view of an exemplary machine 10
is illustrated. The machine 10 is a motor grader 10. The motor
grader 10 is employed to perform earth levelling operation on a
work surface (not shown). The motor grader 10 includes a main frame
12, a number of wheels 14, a cab 16, a power unit 18, a blade
assembly 20, and a drawbar assembly 22.
[0012] The main frame 12 is supported on the wheels 14, which
facilitates machine maneuvering. The main frame 12 supports various
components of the motor grader 10. The main frame 12 includes a
first frame member 24 and a second frame member 26. The first frame
member 24 is positioned proximal to a rear end 28 of the motor
grader 10. The first frame member 24 supports the power unit 18 of
the motor grader 10. The second frame member 26 is an elongated
member rotatably attached to the first frame member 24 of the main
frame 12. The second frame member 26 is positioned proximal to a
frontal end 30 of the motor grader 10. The second frame member 26
supports the cab 16 of the motor grader 10. Additionally, the
second frame member 26 supports the drawbar assembly 22, which in
turn, supports the blade assembly 20 of the motor grader 10.
[0013] The blade assembly 20 includes a blade 32 that performs
levelling operation on the work surface (not shown). The blade 32
is supported on the drawbar assembly 22, via a number of support
members 34. The drawbar assembly 22 is employed to adjust an
orientation of the blade 32, when required. Structure and
arrangement of the drawbar assembly 22 will now be discussed in
detail.
[0014] The drawbar assembly 22 is suspended from the second frame
member 26 and is positioned beneath the second frame member 26. The
drawbar assembly 22 includes a first end portion 36 and a second
end portion 38. The first end portion 36 of the drawbar assembly 22
is coupled to a front section 40 of the second frame member 26. A
universal coupling (not shown) is generally employed to couple the
first end portion 36 to the front section 40 of the second frame
member 26. Although, the universal coupling (not shown) is
described in the present disclosure, various other coupling means
to couple the first end portion 36 with the front section 40 of the
second frame member 26 may also be contemplated.
[0015] The second end portion 38 of the drawbar assembly 22 is
suspended from the second frame member 26, via two control
actuators 42 (one on each side of the motor grader 10). More
specifically, one end of each control actuator 42 is fixedly
attached to the second frame member 26 and other end of each
control actuator 42 is coupled to the drawbar assembly 22.
Additionally, a center shift actuator 43 is positioned between the
second frame member 26 and the drawbar assembly 22, to horizontally
adjust the drawbar assembly 22 when required. The drawbar assembly
22 supports the blade assembly 20 between the first end portion 36
and the second end portion 38.
[0016] Referring to FIG. 2, the drawbar assembly 22 includes a yoke
plate 44, a backbar 46, a first drawbar tube 48, a second drawbar
tube 50, a first sleeve 52, and a second sleeve 54. The yoke plate
44 provides a mounting base for various other components of the
drawbar assembly 22. The yoke plate 44 includes a first surface 56
and a second surface 58. The first surface 56 of the yoke plate 44
faces the second frame member 26. The second surface 58 of the yoke
plate 44 faces the blade assembly 20 (see FIG. 1).
[0017] The backbar 46 is installed on the second end portion 38 of
the drawbar assembly 22. The backbar 46 includes a plate attachment
surface 60 and a tube facing surface 62. The plate attachment
surface 60 of the backbar 46 is fixedly attached to the first
surface 56 of the yoke plate 44, such that the backbar 46 extends
vertically away from the first surface 56 of the yoke plate 44. An
attachment means between the plate attachment surface 60 and the
first surface 56 includes, but is not limited to, an electro-fused
attachment, a weld attachment, an adhesive attachment, a soldered
attachment, a bolt attachment, and a rivet attachment. The tube
facing surface 62 faces the first drawbar tube 48 and the second
drawbar tube 50 of the drawbar assembly 22. Additionally, the
backbar 46 defines a first end section 64 and a second end section
66. Each of the first end section 64 and the second end section 66
includes an actuator mounting section 68. Each control actuator 42
(see FIG. 1) is coupled to the backbar 46 of the drawbar assembly
22 at each actuator mounting section 68 of the first end section 64
and the second end section 66. In an embodiment, each control
actuator 42 is coupled to each actuator mounting section 68 of the
first end section 64 and the second end section 66, by a ball and
stud arrangement.
[0018] The first drawbar tube 48 and the second drawbar tube 50
merge together to form a V-shaped section on the yoke plate 44.
More specifically, each of the first drawbar tube 48 and the second
drawbar tube 50 includes a first end 70, 72, a second end 74, 76,
and a bottom portion 78, 80, respectively. More specifically, the
first ends 70, 72 of the first drawbar tube 48 and the second
drawbar tube 50 are adjoined together, at the first end portion 36
of the drawbar assembly 22. The second ends 74, 76 of the first
drawbar tube 48 and the second drawbar tube 50 respectively are
spaced apart from each other, at the second end portion 38 (see
FIG. 1) of the drawbar assembly 22. Further, the bottom portions
78, 80 of the first drawbar tube 48 and the second drawbar tube 50
are attached to the first surface 56 of the yoke plate 44. The
bottom portions 78, 80 are attached to the first surface 56, such
that a clearance (not shown) is defined between the second ends 74,
76 and the tube facing surface 62 of the backbar 46. For example,
the clearance (not shown) of 4 mm is defined between the second
ends 74, 76 and the tube facing surface 62 of the backbar 46. An
attachment means between the bottom portions 78, 80 and the first
surface 56 includes, but is not limited to, a weld attachment, an
adhesive attachment, a bolt attachment, and a rivet attachment.
[0019] The first sleeve 52 and the second sleeve 54 enclose a
portion of the first drawbar tube 48 and the second drawbar tube
50, respectively. For ease in reference and understanding, a
structure and arrangement of the first sleeve 52 relative to the
first drawbar tube 48 will be explained in detail hereinafter.
However, similar structure and arrangement of the second sleeve 54
relative to the second drawbar tube 50 may also be
contemplated.
[0020] Referring to FIG. 3, the first sleeve 52 is a U-shaped
structure that encloses the portion of the first drawbar tube 48
(see FIG. 2), proximal to the second end 74 (see FIG. 2) of the
first sleeve 52. The first sleeve 52 is relatively thicker than the
first drawbar tube 48. In an embodiment, the first sleeve 52 is
formed from a single plate suitably bent to form the U-shaped
structure. The first sleeve 52 includes a first side portion 86, a
second side portion 88, and a top portion 90. Each of the first
side portion 86 and the second side portion 88 includes a bottom
surface, which in turn defines a yoke attachment portion 82 of the
first sleeve 52. The first side portion 86 and the second side
portion 88, in conjunction with the top portion 90, define a bar
attachment portion 84 of the first sleeve 52. More specifically,
the bar attachment portion 84 is an end face of the first sleeve
52, formed from each of the first side portion 86, the second side
portion 88, and the top portion 90 of the first sleeve 52. The yoke
attachment portions 82 are fixedly attached to the first surface 56
of the yoke plate 44. Referring to FIGS. 2 and 3, the bar
attachment portion 84 is fixedly attached to the tube facing
surface 62 of the backbar 46. With such arrangement, the first
sleeve 52 encloses the portion of the first drawbar tube 48,
proximal to the second end 74 of the first sleeve 52. An attachment
means between the bar attachment portion 84 and the tube facing
surface 62 may include, but is not limited to, a weld attachment,
an adhesive attachment, a bolt attachment, and a rivet attachment.
Similar attachment means between the yoke attachment portions 82
and the first surface 56 of the yoke plate 44, may also be
contemplated.
[0021] Referring to FIG. 4 an alternate embodiment of a first
sleeve 92 is illustrated. The first sleeve 92 is formed from three
individual plates, namely a first side plate 98, a second side
plate 100, and a top plate 102. Each of the first side plate 98 and
the second side plate 100 is attached to the top plate 102, to form
a U-shaped cross section. The first side plate 98 and the second
side plate 100 define two yoke attachment portions 94 of the first
sleeve 92. The first side plate 98 and the second side plate 100,
in conjunction with the top plate 102 define a bar attachment
portion 96 of the first sleeve 92. Referring to FIGS. 2 and 4, the
yoke attachment portions 82, 94 are fixedly attached to the first
surface 56 of the yoke plate 44 and the bar attachment portion 84,
96 is attached to the tube facing surface 62 of the backbar 46, to
cover the second end 74 of the first drawbar tube 48. In an
embodiment, the second sleeve 54 may be contemplated to possess
similar structure and arrangement as that of the alternate
embodiment of the first sleeve 92.
INDUSTRIAL APPLICABILITY
[0022] In operation, the drawbar assembly 22 is employed to support
the blade assembly 20 of the motor grader 10. The drawbar assembly
22 includes the yoke plate 44, the backbar 46, the first drawbar
tube 48, the second drawbar tube 50, the first sleeve 52, 92, and
the second sleeve 54. The backbar 46 is attached to the first
surface 56 of the yoke plate 44, extending vertically away from the
first surface 56 of the yoke plate 44. The bottom portions 78, 80
of the first drawbar tube 48 and the second drawbar tube 50 are
attached to the first surface 56 of the yoke plate 44, such that,
the clearance (not shown) is defined between the second ends 74, 76
and the tube facing surface 62 of the backbar 46.
[0023] Furthermore, the first sleeve 52, 92, and the second sleeve
54 are provided to cover the portion of the first drawbar tube 48
and the second drawbar tube 50, respectively. For ease in reference
and understanding, structure and arrangement of the first sleeve
52, 92 relative to the first drawbar tube 48 will be explained in
details hereinafter. Similar structure and arrangement of the
second sleeve 54 relative to the second drawbar tube 50 may also be
contemplated. The first sleeve 52, 92 encloses the portion of the
first drawbar tube 48, such that the bar attachment portion 84, 96
is attached to the tube facing surface 62 of the backbar 46 and the
yoke attachment portions 82, 94 is attached to the first surface 56
of the yoke plate 44.
[0024] With such arrangement of the drawbar assembly 22, the load
is transferred from the first drawbar tube 48 to the backbar 46,
via the first sleeve 52, 92. Consequently, the first drawbar tube
48 may be precluded from stress corresponding to the increased
load. Moreover, as the first sleeve 52, 92 is relatively thicker
than the backbar 46, the increased load may be uniformly
distributed on the first sleeve 52, 92. Therefore, the first sleeve
52, 92 may undergo relatively less stress. Hence, work life of the
first drawbar tube 48 may be improved. Similar to the first sleeve
52, 92, the second sleeve 54 may enhance the work life of the
second drawbar tube 50. Therefore, the disclosed drawbar assembly
22 may enhance the work life of the first drawbar tube 48 and the
second drawbar tube 50. This, in turn, may correspond to relatively
lower service costs and relatively less repair time.
[0025] While aspects of the present disclosure have been
particularly shown and described with reference to the embodiments
above, it will be understood by those skilled in the art that
various additional embodiments may be contemplated by the
modification of the disclosed machines, systems and methods without
departing from the spirit and scope of the disclosure. Such
embodiments should be understood to fall within the scope of the
present disclosure as determined based upon the claims and any
equivalents thereof.
* * * * *